1
|
Sultana R, Cordeiro RP, Timsit E, McAllister TA, Alexander TW. Prevalence and antimicrobial susceptibility of Mycoplasma bovis from the upper and lower respiratory tracts of healthy feedlot cattle and those diagnosed with bovine respiratory disease. Vet Microbiol 2023; 285:109838. [PMID: 37690145 DOI: 10.1016/j.vetmic.2023.109838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 06/14/2023] [Accepted: 07/27/2023] [Indexed: 09/12/2023]
Abstract
Mycoplasma bovis is an important respiratory pathogen of cattle. In this study, the prevalence and antimicrobial susceptibility of M. bovis were evaluated from two Cohorts of feedlot cattle spanning an 8-year period. In the first study conducted in 2008-2009, nasopharyngeal swabs from cattle sampled at feedlot entry and after 60 days on feed were collected (Cohort 1). In a second study conducted in 2015-2016, nasopharyngeal and trans-tracheal samples were collected from cattle diagnosed with bovine respiratory disease (BRD) and matching healthy controls (Cohort 2). For Cohort 1, the prevalence of M. bovis was lower in cattle at entry compared to when the same individuals were sampled ≥60 days later (P < 0.05). For Cohort 2, the prevalence of M. bovis was greater in both nasopharyngeal and tracheal samples from cattle diagnosed with BRD, compared to controls (P < 0.05). In both Cohorts, almost all isolates were resistant to tilmicosin. Compared to M. bovis from Cohort 1, isolates of Cohort 2 exhibited increased resistance to clindamycin, enrofloxacin, florfenicol, tylosin, and tulathromycin, with the latter showing resistance levels >90 %. These data suggest that antimicrobials used to prevent and treat BRD selected for resistance in M. bovis over the 8-year period. For macrolides, cross-resistance occurred and M. bovis can retain resistance even when antimicrobial selection pressure is removed. Within 9 years of commercial availability of tulathromycin, the majority of M. bovis displayed resistance. Therefore, longitudinal evaluation of resistance in respiratory pathogens is important to ensure efficacious treatment of BRD.
Collapse
Affiliation(s)
- Razia Sultana
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada; Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Roniele P Cordeiro
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada
| | - Edouard Timsit
- Department of Pharma Innovation, Ceva Santé Animale, Libourne, France
| | - Tim A McAllister
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada
| | - Trevor W Alexander
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada.
| |
Collapse
|
2
|
Amat S, Timsit E, Workentine M, Schwinghamer T, van der Meer F, Guo Y, Alexander TW. A Single Intranasal Dose of Bacterial Therapeutics to Calves Confers Longitudinal Modulation of the Nasopharyngeal Microbiota: a Pilot Study. mSystems 2023; 8:e0101622. [PMID: 36971568 PMCID: PMC10134831 DOI: 10.1128/msystems.01016-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023] Open
Abstract
Bovine respiratory disease (BRD) remains the most significant health challenge affecting the North American beef cattle industry and results in $3 billion in economic losses yearly. Current BRD control strategies mainly rely on antibiotics, with metaphylaxis commonly employed to mitigate BRD incidence in commercial feedlots.
Collapse
|
3
|
Durunna O, Carroll JA, Dailey JW, Damiran D, Larson KA, Timsit E, Parsons R, Manafiazar G, Lardner HA. Corrigendum: Phenotypic and genetic parameters of circadian rhythms from core body temperature profiles and their relationships with beef steers' production efficiency profiles during successive winter feeding periods. Front Genet 2023; 14:1154825. [PMID: 36845404 PMCID: PMC9950930 DOI: 10.3389/fgene.2023.1154825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/12/2023] Open
Abstract
[This corrects the article DOI: 10.3389/fgene.2023.1026601.].
Collapse
Affiliation(s)
- Obioha Durunna
- Department of Applied Research, Lakeland College, Vermilion, AB, Canada,Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK, Canada,*Correspondence: Obioha Durunna,
| | | | - Jeff W. Dailey
- USDA ARS Livestock Issues Research Unit, Lubbock, TX, United States
| | - Daalkhaijav Damiran
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK, Canada
| | - Kathy A. Larson
- Department of Agricultural and Resource Economics, University of Saskatchewan, Saskatoon, SK, Canada
| | - Edouard Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Rex Parsons
- Australian Centre for Health Services Innovation and Centre for Healthcare Transformation, School of Public Health and Social Work, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD, Australia
| | - Ghader Manafiazar
- Animal Science and Aquaculture Department, Faculty of Agriculture, Dalhousie University, Halifax, NS, Canada
| | - Herbert A. Lardner
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK, Canada
| |
Collapse
|
4
|
Hirsch C, Timsit E, Uddin MS, Guan LL, Alexander TW. Comparison of pathogenic bacteria in the upper and lower respiratory tracts of cattle either directly transported to a feedlot or co-mingled at auction markets prior to feedlot placement. Front Vet Sci 2023; 9:1026470. [PMID: 36761402 PMCID: PMC9902877 DOI: 10.3389/fvets.2022.1026470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/29/2022] [Indexed: 01/26/2023] Open
Abstract
Introduction Bacterial bronchopneumonia (BP) has been associated with purchasing cattle through auction markets. However, whether auction markets are a source of BP-associated bacterial pathogens is unknown. This study evaluated prevalence, antimicrobial susceptibility, and genetic relatedness (using pulsed-field gel electrophoresis, PFGE) of Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni isolated from cattle either transported to an auction market prior to feedlot placement (AUC), or directly to a feedlot from a farm (RANC). Methods Two groups of cattle were enrolled (N = 30 per group) from two separate farms with 15 animals from an individual farm designated as AUC or RANC. Deep nasal swab (DNS) and trans-tracheal aspirates (TTA) were collected on day 0 at weaning (T0) and on day 2 at on-arrival processing at the feedlot (T1). The DNS were also collected on day 9 (T2) and day 30 (T3) after arrival at the feedlot. Results and discussion In both TTA and DNS, prevalence of bacteria did not differ between AUC and RANC groups (P > 0.05). None of the bacteria isolated at T0 were resistant to antimicrobials and diversity of all bacteria was greatest at T0 and T1. In Group 1 cattle, 100% of P. multocida isolated at T2 and T3 were multi-drug resistant. These isolates were highly related (>90%) according to PFGE, with most being clones. Though limited in size, results for animals evaluated in this study suggested that auction markets were not a major source of resistant BP pathogens, however, horizontal transmission of a multi-resistant strain of P. multocida occurred in a feedlot. Spread of resistant P. multocida was likely due to the selective pressures imposed by feedlot antimicrobial use and encoded resistance by the bacteria.
Collapse
Affiliation(s)
| | | | - Muhammed Salah Uddin
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada,Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Le Luo Guan
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Trevor W. Alexander
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada,*Correspondence: Trevor W. Alexander
| |
Collapse
|
5
|
Durunna O, Carroll JA, Dailey JW, Damiran D, Larson KA, Timsit E, Parsons R, Manafiazar G, Lardner HA. Phenotypic and genetic parameters of circadian rhythms from core body temperature profiles and their relationships with beef steers' production efficiency profiles during successive winter feeding periods. Front Genet 2023; 14:1026601. [PMID: 36741324 PMCID: PMC9893500 DOI: 10.3389/fgene.2023.1026601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 01/06/2023] [Indexed: 01/20/2023] Open
Abstract
This 2-year study evaluated differences in circadian parameters obtained from measures of core body temperatures using telemetric reticulo-rumen and rectal devices during two winter feeding regimes in western Canada. The study also estimated phenotypic correlations and genetic parameters associated with circadian parameters and other production traits in each feeding regime. Each year, 80 weaned steer calves (initial age: 209 ± 11 days; BW: 264 ± 20 kg) from the same cohort were tested over two successive regimes, Fall-Winter (FW) and Winter-Spring (WS) at Lanigan, Saskatchewan, Canada. The steers received forage-based rations in both regimes where the individual feed intake was measured with automatic feeding units. During the trial, the reticulo-rumen (RTMP) and rectal (RCT) temperatures were simultaneously measured every 5 min using telemetric devices. These were used to calculate the circadian parameters (Midline Estimating Statistic Of Rhythms, amplitude, and acrophase/peak time) for both temperature measures. Growth and efficiency performance traits were also determined for all steers. Each steer was assigned into inefficient, neutral, and efficient classes based on the SD of the residual feed intake (RFI), residual gain (RG), and residual intake and gain (RIG) within each year and feeding regime. Higher (p < 0.0003) RTMP and rectal temperature MESORs were observed in the Fall-Winter compared to the Winter-Spring regime. While the two test regimes were different (p < 0.05) for the majority of the RTMP or RCT temperature parameters, they did not differ (p > 0.10) with the production efficiency profiles. The heritability estimates were higher in FW (0.78 ± 0.18 vs. 0.56 ± 0.26) than WS (0.50 ± 0.18 vs. 0.47 ± 0.22) for the rumen and rectal MESORs, respectively. There were positive genetic correlations between the two regimes for the RTMP (0.69 ± 0.21) and RCT (0.32 ± 0.59). There was a negative correlation (p < 0.001) between body temperature and ambient temperature. The high heritability estimates and genetic correlations for rumen and rectal temperature parameters demonstrate their potential as beef genetic improvement tools of economic traits associated with the parameters. However, there are limited practical implications of using only the core-body temperature as a proxy for production efficiency traits for beef steers during winter.
Collapse
Affiliation(s)
- Obioha Durunna
- Department of Applied Research, Lakeland College, Vermilion, AB, Canada,Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK, Canada,*Correspondence: Obioha Durunna,
| | | | - Jeff W. Dailey
- USDA ARS Livestock Issues Research Unit, Lubbock, TX, United States
| | - Daalkhaijav Damiran
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK, Canada
| | - Kathy A. Larson
- Department of Agricultural and Resource Economics, University of Saskatchewan, Saskatoon, SK, Canada
| | - Edouard Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Rex Parsons
- Australian Centre for Health Services Innovation and Centre for Healthcare Transformation, School of Public Health and Social Work, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD, Australia
| | - Ghader Manafiazar
- Animal Science and Aquaculture Department, Faculty of Agriculture, Dalhousie University, Halifax, NS, Canada
| | - Herbert A. Lardner
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK, Canada
| |
Collapse
|
6
|
Bond S, McMullen C, Timsit E, Léguillette R. Topography of the respiratory, oral, and guttural pouch bacterial and fungal microbiotas in horses. J Vet Intern Med 2023; 37:349-360. [PMID: 36607177 PMCID: PMC9889660 DOI: 10.1111/jvim.16612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 12/08/2022] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The lower respiratory tract microbiota of the horse is different in states of health and disease, but the bacterial and fungal composition of the healthy respiratory tract of the horse has not been studied in detail. HYPOTHESIS The respiratory tract environment contains distinct niche microbiotas, which decrease in species richness at more distal sampling locations. OBJECTIVE Characterize the bacterial and fungal microbiotas along the upper and lower respiratory tract of the horse. ANIMALS Healthy Argentinian Thoroughbred horses (n = 11) from the same client-owned herd. METHODS Prospective cross-sectional study. Eleven upper and lower respiratory tract anatomical locations (bilateral nasal, bilateral deep nasal, nasopharynx, floor of mouth, oropharynx, arytenoids, proximal and distal trachea, guttural pouch) were sampled using a combination of swabs, protected specimen brushes, and saline washes. Total DNA was extracted from each sample and negative control, and the 16S rRNA gene (V4) and ITS2 region were sequenced. Community composition, alpha-diversity, and beta-diversity were compared among sampling locations. RESULTS Fungal species richness and diversity were highest in the nostrils. More spatial heterogeneity was found in bacterial composition than in fungal communities. The pharyngeal microbiota was most similar to the distal tracheal bacterial and fungal microbiota in healthy horses and therefore may serve as the primary source of bacteria and fungi to the lower respiratory tract. CONCLUSIONS AND CLINICAL IMPORTANCE The pharynx is an important location that should be targeted in respiratory microbiota research in horses. Future studies that investigate whether biomarkers of respiratory disease can be reliably detected in nasopharyngeal swab samples are warranted.
Collapse
Affiliation(s)
- Stephanie Bond
- Faculty of Veterinary MedicineUniversity of CalgaryCalgaryAlbertaCanada,School of Veterinary Science, Faculty of ScienceUniversity of QueenslandGattonAustralia
| | - Christopher McMullen
- Faculty of Veterinary MedicineUniversity of CalgaryCalgaryAlbertaCanada,Feedlot Health Management Services, IncOkotoksAlbertaCanada
| | - Edouard Timsit
- Faculty of Veterinary MedicineUniversity of CalgaryCalgaryAlbertaCanada,I&D Pharma DepartementCeva Santé AnimaleLibourneFrance
| | | |
Collapse
|
7
|
Li J, Mukiibi R, Jiminez J, Wang Z, Akanno EC, Timsit E, Plastow GS. Applying multi-omics data to study the genetic background of bovine respiratory disease infection in feedlot crossbred cattle. Front Genet 2022; 13:1046192. [PMID: 36579334 PMCID: PMC9790935 DOI: 10.3389/fgene.2022.1046192] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
Bovine respiratory disease (BRD) is the most common and costly infectious disease affecting the wellbeing and productivity of beef cattle in North America. BRD is a complex disease whose development is dependent on environmental factors and host genetics. Due to the polymicrobial nature of BRD, our understanding of the genetic and molecular mechanisms underlying the disease is still limited. This knowledge would augment the development of better genetic/genomic selection strategies and more accurate diagnostic tools to reduce BRD prevalence. Therefore, this study aimed to utilize multi-omics data (genomics, transcriptomics, and metabolomics) analyses to study the genetic and molecular mechanisms of BRD infection. Blood samples of 143 cattle (80 BRD; 63 non-BRD animals) were collected for genotyping, RNA sequencing, and metabolite profiling. Firstly, a genome-wide association study (GWAS) was performed for BRD susceptibility using 207,038 SNPs. Two SNPs (Chr5:25858264 and BovineHD1800016801) were identified as associated (p-value <1 × 10-5) with BRD susceptibility. Secondly, differential gene expression between BRD and non-BRD animals was studied. At the significance threshold used (log2FC>2, logCPM>2, and FDR<0.01), 101 differentially expressed (DE) genes were identified. These DE genes significantly (p-value <0.05) enriched several immune responses related functions such as inflammatory response. Additionally, we performed expression quantitative trait loci (eQTL) analysis and identified 420 cis-eQTLs and 144 trans-eQTLs significantly (FDR <0.05) associated with the expression of DE genes. Interestingly, eQTL results indicated the most significant SNP (Chr5:25858264) identified via GWAS was a cis-eQTL for DE gene GPR84. This analysis also demonstrated that an important SNP (rs209419196) located in the promoter region of the DE gene BPI significantly influenced the expression of this gene. Finally, the abundance of 31 metabolites was significantly (FDR <0.05) different between BRD and non-BRD animals, and 17 of them showed correlations with multiple DE genes, which shed light on the interactions between immune response and metabolism. This study identified associations between genome, transcriptome, metabolome, and BRD phenotype of feedlot crossbred cattle. The findings may be useful for the development of genomic selection strategies for BRD susceptibility, and for the development of new diagnostic and therapeutic tools.
Collapse
Affiliation(s)
- Jiyuan Li
- Livestock Gentec, Department of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Robert Mukiibi
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Janelle Jiminez
- Livestock Gentec, Department of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Zhiquan Wang
- Livestock Gentec, Department of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Everestus C. Akanno
- Livestock Gentec, Department of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Graham S. Plastow
- Livestock Gentec, Department of Agriculture, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada,*Correspondence: Graham S. Plastow,
| |
Collapse
|
8
|
Flattot EAL, Batterham TR, Timsit E, White BJ, McMeniman JP, Ward MP, González LA. Evaluation of reticulorumen temperature boluses for the diagnosis of subclinical cases of bovine respiratory disease in feedlot cattle. J Anim Sci 2021; 99:6426233. [PMID: 34788846 DOI: 10.1093/jas/skab337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 11/10/2021] [Indexed: 11/14/2022] Open
Abstract
Bovine respiratory disease (BRD) is the most important and costly health issue of the feedlot industry worldwide. Remote monitoring of reticulorumen temperature has been suggested as a potential tool to improve the diagnostic accuracy of BRD. The present study aimed to evaluate 1) the difference and degree of reticulorumen hyperthermia episodes between healthy and subclinical BRD feedlot steers, and 2) determine the correlation between reticulorumen hyperthermia and lung pathology, performance, and carcass traits. Mixed-breed feedlot steers (n = 148) with a mean arrival weight of 321 ± 3.34 kg were administered a reticulorumen bolus at feedlot entry and monitored for visual and audible signs of BRD until slaughter when lungs were examined and scored for lesions indicative of BRD. Post-slaughter animals with no record of BRD treatment were assigned to one of three case definitions. Healthy steers had no visual or audible signs of BRD (i.e., CIS=1), and total lung consolidation score < 5% or pleurisy score < 3 at slaughter. Subclinical BRD cases had a CIS of 1, and a lung consolidation score ≥ 5% or a pleurisy score of 3 at slaughter. Mild CIS cases had at least one CIS of 2, and a lung consolidation score < 5% and a pleurisy score < 3 at slaughter. Subclinical BRD and mild CIS cases had longer total duration of reticulorumen hyperthermia, more episodes and longer average episode duration above 40.0 °C compared to healthy steers (P < 0.05). A moderate positive correlation was found between lung consolidation and total duration (r = 0.27, P < 0.001), episode duration (r = 0.29, P < 0.001), and number of episodes (r = 0.20, P < 0.05). Pleurisy score was also found to be moderately and positively correlated with total duration (r = 0.23, P < 0.01), episode duration (r = 0.37, P < 0.001), and number of episodes (r = 0.26, P < 0.01). Moderate negative correlations were found between reticulorumen hyperthermia and carcass traits including hot standard carcass weight (HSCW) (-0.22 ≤ r ≤ -0.23, P < 0.05) and P8-fat depth (-0.18 ≤ r ≤ -0.32, P < 0.05). Subclinical BRD reduced carcass weight by 22 kg and average daily gain (ADG) by 0.44 kg/day compared to healthy steers (P < 0.05), but mild CIS cases had no effect on performance (P > 0.05). The reticulorumen bolus technology appears promising for detection of subclinical BRD cases in feedlot cattle as defined by lung pathology at slaughter.
Collapse
Affiliation(s)
- Emilie A-L Flattot
- Apiam Animal Health, East Bendigo, Victoria 3550, Australia.,School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Camden, NSW 2570, Australia
| | - Tony R Batterham
- Apiam Animal Health, East Bendigo, Victoria 3550, Australia.,School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Camden, NSW 2570, Australia.,Quirindi Feedlot Services, Quirindi, NSW 2343, Australia
| | - Edouard Timsit
- Innovation Department, CEVA Santé Animal, Libourne 33500, France
| | - Brad J White
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | | | - Michael P Ward
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Camden, NSW 2570, Australia
| | - Luciano A González
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Camden, NSW 2570, Australia.,Sydney Institute of Agriculture, University of Sydney, Sydney, NSW 2015, Australia
| |
Collapse
|
9
|
Buczinski S, Achard D, Timsit E. Effects of calfhood respiratory disease on health and performance of dairy cattle: A systematic review and meta-analysis. J Dairy Sci 2021; 104:8214-8227. [PMID: 33896639 DOI: 10.3168/jds.2020-19941] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 03/19/2021] [Indexed: 12/13/2022]
Abstract
Bovine respiratory disease (BRD) is one of the most common calfhood diseases in dairy cattle. Unfortunately, published data on the short- and long-term effects of calfhood BRD on health and performance are scarce and, when available, often conflicting and uncertain. The objective of this study was therefore to review the scientific literature on the effects of calfhood BRD on health and performance of dairy cattle and summarize the research findings using a meta-analysis approach. The systematic review and meta-analysis were performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed and CAB Abstract databases were screened for relevant studies that were published in English (until February 3, 2020). Only studies reporting naturally occurring BRD cases from birth to 12 mo of age in dairy calves in Europe and North America were considered eligible. Both observational studies and randomized controlled trials were included. Random-effect meta-analysis models were used to quantify the effect of BRD on outcomes for which at least 5 studies reported a numeric estimation of the effect of BRD. From an initial pool of 525 references, 27 full-text articles with original data were included in the manuscript. Meta-analysis models were prepared for 4 outcomes: odds of mortality (n = 7 studies), odds of herd removal before first calving (n = 5 studies), average daily gain (n = 10 studies), and milk production during first lactation (n = 5 studies). In these models, heifers diagnosed with BRD during calfhood had 2.85 times higher odds of dying (95% confidence interval: 1.22 to 6.69) and 2.30 times higher odds of herd removal (i.e., dead, culled, or sold) before the first calving (95% confidence interval: 1.75 to 3.03) compared with heifers not diagnosed with this condition. Heifers experiencing calfhood BRD also had an average daily gain reduced by 0.067 kg/d (95% confidence interval: -0.099 to -0.034) and they produced 121.2 kg (95% confidence interval: -184.9 to -57.5) less milk during their first lactation. Other health and performance outcomes, such as age at first calving and odds of not finishing the first lactation, were also investigated but not summarized using a meta-analysis approach. Pooled estimates obtained in the present study may provide more accurate estimates of the overall economic losses associated with calfhood BRD in dairy cattle.
Collapse
Affiliation(s)
- S Buczinski
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC, Canada J2S 2M2; Centre d'expertise et de recherche clinique en santé et bien-être animal, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC, Canada J2S 2M2.
| | - D Achard
- Ceva Santé Animale, Libourne, France 33100
| | - E Timsit
- Ceva Santé Animale, Libourne, France 33100; Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, AB, Canada T2N 4N1.
| |
Collapse
|
10
|
Jiminez J, Timsit E, Orsel K, van der Meer F, Guan LL, Plastow G. Whole-Blood Transcriptome Analysis of Feedlot Cattle With and Without Bovine Respiratory Disease. Front Genet 2021; 12:627623. [PMID: 33763112 PMCID: PMC7982659 DOI: 10.3389/fgene.2021.627623] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 02/08/2021] [Indexed: 12/13/2022] Open
Abstract
Bovine respiratory disease (BRD) is one of the main factors leading to morbidity and mortality in feedlot operations in North America. A complex of viral and bacterial pathogens can individually or collectively establish BRD in cattle, and to date, most disease characterization studies using transcriptomic techniques examine bronchoalveolar and transtracheal fluids, lymph node, and lung tissue as well as nasopharyngeal swabs, with limited studies investigating the whole-blood transcriptome. Here, we aimed to identify differentially expressed (DE) genes involved in the host immune response to BRD using whole blood and RNA sequencing. Samples were collected from heifers (average arrival weight = 215.0 ± 5.3 kg) with (n = 25) and without (n = 18) BRD at a commercial feedlot in Western Canada. RNAseq analysis showed a distinct whole-blood transcriptome profile between BRD and non-BRD heifers. Further examination of the DE genes revealed that those involved in the host inflammatory response and infectious disease pathways were enriched in the BRD animals, while gene networks associated with metabolism and cell growth and maintenance were downregulated. Overall, the transcriptome profile derived from whole blood provided evidence that a distinct antimicrobial peptide-driven host immune response was occurring in the animals with BRD. The blood transcriptome of the BRD animals shows similarities to the transcriptome profiles obtained from lung and bronchial lymph nodes in other studies. This suggests that the blood transcriptome is a potential diagnostic tool for the identification of biomarkers of BRD infection and can be measured in live animals and used to further understand infection and disease in cattle. It may also provide a useful tool to increase the understanding of the genes involved in establishing BRD in beef cattle and be used to investigate potential therapeutic applications.
Collapse
Affiliation(s)
- Janelle Jiminez
- Department of Agricultural, Food and Nutritional Science, Livestock Gentec, University of Alberta, Edmonton, AB, Canada
| | - Edouard Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.,Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada.,Ceva Santé Animale, Libourne, France
| | - Karin Orsel
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Frank van der Meer
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Le Luo Guan
- Department of Agricultural, Food and Nutritional Science, Livestock Gentec, University of Alberta, Edmonton, AB, Canada
| | - Graham Plastow
- Department of Agricultural, Food and Nutritional Science, Livestock Gentec, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
11
|
Humblot E, Ray P, Timsit E. Une dermatose au shiitake. Ann Fr Med Urgence 2020. [DOI: 10.3166/afmu-2020-0273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
12
|
McMullen C, Alexander TW, Orsel K, Timsit E. Progression of nasopharyngeal and tracheal bacterial microbiotas of feedlot cattle during development of bovine respiratory disease. Vet Microbiol 2020; 248:108826. [PMID: 32891954 DOI: 10.1016/j.vetmic.2020.108826] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 08/13/2020] [Indexed: 01/04/2023]
Abstract
It is generally accepted that as bovine respiratory disease (BRD) develops, bacterial pathogens first proliferate in the nasopharynx and then colonize the lungs, leading to bronchopneumonia. However, such temporal changes have never been definitively demonstrated. Therefore, the objective was to describe the progression of the nasopharyngeal and tracheal bacterial microbiotas of feedlot cattle during development of BRD. Nasopharyngeal swabs and tracheal wash samples were collected from 24 heifers over 20 d after arrival at a feedlot. Heifers were assessed daily and sampled based on reticulo-rumen/rectal temperatures and development of clinical signs of BRD. The study end point for each heifer was either at BRD treatment (BRD group; n = 15) or day 20 if the heifer remained healthy or did not meet BRD treatment criteria (TOL group; n = 9). Total DNA was extracted from each sample and the 16S rRNA gene (V3-V4) sequenced. Alpha and beta diversity were compared between BRD-TOL groups and sampling locations over time. There were no common patterns of change over time in composition or diversity of either the nasopharyngeal or tracheal bacterial microbiotas of cattle that developed BRD. Health status affected bacterial composition (R2 = 0.043; < 0.001), though this effect was low compared to variation among individual animals (R2 = 0.335; < 0.001) and effects of days on feed (R2 = 0.082; < 0.001). Specific bacterial taxa (Moraxella and Mycoplasma dispar) nevertheless appeared to have a potential role in respiratory health.
Collapse
Affiliation(s)
| | - Trevor W Alexander
- Lethbridge Research and Development Center, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - Karin Orsel
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada; Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada; Ceva Santé Animale, Libourne, France.
| |
Collapse
|
13
|
Timsit E, McMullen C, Amat S, Alexander TW. Respiratory Bacterial Microbiota in Cattle: From Development to Modulation to Enhance Respiratory Health. Vet Clin North Am Food Anim Pract 2020; 36:297-320. [PMID: 32451027 DOI: 10.1016/j.cvfa.2020.03.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The respiratory tract of cattle is colonized by complex bacterial ecosystems also known as bacterial microbiotas. These microbiotas evolve over time and are shaped by numerous factors, including maternal vaginal microbiota, environment, age, diet, parenteral antimicrobials, and stressful events. The resulting microbiota can be diverse and enriched with known beneficial bacteria that can provide colonization resistance against bacterial pathogens or, on the contrary, with opportunistic pathogens that can predispose cattle to respiratory disease. The respiratory microbiota can be modulated by nonantimicrobial approaches to promote health, creating new potential strategies for prevention and treatment of bovine respiratory disease.
Collapse
Affiliation(s)
- Edouard Timsit
- Ceva Santé Animale, 10 Avenue de la Ballastière, Libourne 33500, France.
| | - Chris McMullen
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Samat Amat
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada; Lethbridge Research and Development Center, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada; Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Trevor W Alexander
- Lethbridge Research and Development Center, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada
| |
Collapse
|
14
|
McMullen C, Alexander TW, Léguillette R, Workentine M, Timsit E. Topography of the respiratory tract bacterial microbiota in cattle. Microbiome 2020; 8:91. [PMID: 32522285 PMCID: PMC7288481 DOI: 10.1186/s40168-020-00869-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/13/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Bacterial bronchopneumonia (BP) is the leading cause of morbidity and mortality in cattle. The nasopharynx is generally accepted as the primary source of pathogenic bacteria that cause BP. However, it has recently been shown in humans that the oropharynx may act as the primary reservoir for pathogens that reach the lung. The objective was therefore to describe the bacterial microbiota present along the entire cattle respiratory tract to determine which upper respiratory tract (URT) niches may contribute the most to the composition of the lung microbiota. METHODS Seventeen upper and lower respiratory tract locations were sampled from 15 healthy feedlot steer calves. Samples were collected using a combination of swabs, protected specimen brushes, and saline washes. DNA was extracted from each sample and the 16S rRNA gene (V3-V4) was sequenced. Community composition, alpha-diversity, and beta-diversity were compared among sampling locations. RESULTS Microbiota composition differed across sampling locations, with physiologically and anatomically distinct locations showing different relative abundances of 1137 observed sequence variants (SVs). An analysis of similarities showed that the lung was more similar to the nasopharynx (R-statistic = 0.091) than it was to the oropharynx (R-statistic = 0.709) or any other URT sampling location. Five distinct metacommunities were identified across all samples after clustering at the genus level using Dirichlet multinomial mixtures. This included a metacommunity found primarily in the lung and nasopharynx that was dominated by Mycoplasma. Further clustering at the SV level showed a shared metacommunity between the lung and nasopharynx that was dominated by Mycoplasma dispar. Other metacommunities found in the nostrils, tonsils, and oral microbiotas were dominated by Moraxella, Fusobacterium, and Streptococcus, respectively. CONCLUSIONS The nasopharyngeal bacterial microbiota is most similar to the lung bacterial microbiota in healthy cattle and therefore may serve as the primary source of bacteria to the lung. This finding indicates that the nasopharynx is likely the most important location that should be targeted when doing bovine respiratory microbiota research. Video abstract.
Collapse
Affiliation(s)
| | - Trevor W. Alexander
- Lethbridge Research and Development Center, Agriculture and Agri-Food Canada, Lethbridge, Alberta Canada
| | - Renaud Léguillette
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta Canada
| | - Matthew Workentine
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta Canada
- Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, Alberta Canada
- Ceva Santé Animale, 10 Avenue de la Ballastière, 33500 Libourne, France
| |
Collapse
|
15
|
Amat S, Alexander TW, Holman DB, Schwinghamer T, Timsit E. Intranasal Bacterial Therapeutics Reduce Colonization by the Respiratory Pathogen Mannheimia haemolytica in Dairy Calves. mSystems 2020; 5:e00629-19. [PMID: 32127421 PMCID: PMC7055656 DOI: 10.1128/msystems.00629-19] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 12/10/2019] [Indexed: 01/27/2023] Open
Abstract
Six Lactobacillus strains originating from the nasopharyngeal microbiota of cattle were previously characterized in vitro and identified as candidate bacterial therapeutics (BTs) for mitigating the bovine respiratory pathogen Mannheimia haemolytica In the present study, these BT strains were evaluated for their potential to (i) reduce nasal colonization by M. haemolytica, (ii) modulate the nasal microbiota, and (iii) stimulate an immune response in calves experimentally challenged with M. haemolytica. Twenty-four Holstein bull calves (1 to 3 weeks old) received either an intranasal BT cocktail containing 6 Lactobacillus strains (3 × 109 CFU per strain; BT + Mh group) 24 h prior to intranasal M. haemolytica challenge (3 × 108 CFU) or no BTs prior to challenge (Mh, control group). Nasal swab, blood, and transtracheal aspiration samples were collected over the course of 16 days after BT inoculation. Counts of M. haemolytica were determined by culturing, and the nasal and tracheal microbiotas were evaluated using 16S rRNA gene sequencing. Serum cytokines (interleukin-6 [IL-6], IL-8, and IL-10) were quantified by enzyme-linked immunosorbent assay (ELISA). Administration of BT reduced nasal colonization by M. haemolytica (P = 0.02), modified the composition and diversity of the nasal microbiota, and altered interbacterial relationships among the 10 most relatively abundant genera. The BT + Mh calves also had a lower relative abundance of Mannheimia in the trachea (P < 0.01) but similar cytokine levels as Mh calves. This study demonstrated that intranasal BTs developed from the bovine nasopharyngeal Lactobacillus spp. were effective in reducing nasal colonization by M. haemolytica in dairy calves.IMPORTANCE Bovine respiratory disease (BRD) is one of the significant challenges for the modern dairy industry in North America, accounting for 23 to 47% of the total mortality among pre- and postweaned dairy heifers. Mass medication with antibiotics is a common practice to control BRD in dairy cattle. However, the emergence of multidrug-resistant BRD pathogens highlights the importance of developing alternatives to antibiotics for BRD mitigation. Using a targeted approach, we recently identified 6 Lactobacillus strains originating from the bovine respiratory microbiota as candidates to be used as bacterial therapeutics (BTs) for the mitigation of the BRD pathogen Mannheimia haemolytica Here, we demonstrated that intranasal inoculation of the BT strains reduced nasal colonization by M. haemolytica in dairy calves experimentally challenged with this pathogen. This study, for the first time, shows the potential use of intranasal BTs as an alternative to mitigate BRD pathogens in cattle.
Collapse
Affiliation(s)
- Samat Amat
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Trevor W Alexander
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
| | - Devin B Holman
- Lacombe Research and Development Centre, Agriculture and Agri-Food Canada, Lacombe, Alberta, Canada
| | - Timothy Schwinghamer
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
- Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, Alberta, Canada
- CEVA Santé Animale, Libourne, France
| |
Collapse
|
16
|
Damiran D, Durunna O, Timsit E, Campbell JR, Larson KA, Carroll JA, Dailey JW, Lardner B. Evaluating core body temperature and lying behavior as an indicator of feed efficiency profile of beef cattle-consuming forage-based diets. Transl Anim Sci 2019; 3:1632-1635. [PMID: 32704926 PMCID: PMC6999136 DOI: 10.1093/tas/txz044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 04/29/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Daalkhaijav Damiran
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada
| | - Obioha Durunna
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada.,Lakeland College, Vermilion, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada
| | - John R Campbell
- Large Animal Clinical Sciences, Western College of Veterinary Medicine, Saskatoon, Canada
| | - Kathy A Larson
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada
| | | | | | - Bart Lardner
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada
| |
Collapse
|
17
|
Amat S, Timsit E, Baines D, Yanke J, Alexander TW. Development of Bacterial Therapeutics against the Bovine Respiratory Pathogen Mannheimia haemolytica. Appl Environ Microbiol 2019; 85:e01359-19. [PMID: 31444198 PMCID: PMC6803296 DOI: 10.1128/aem.01359-19] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 07/23/2019] [Indexed: 12/21/2022] Open
Abstract
Bovine respiratory disease (BRD) is a major cause of morbidity and mortality in beef cattle. Recent evidence suggests that commensal bacteria of the bovine nasopharynx have an important role in maintaining respiratory health by providing colonization resistance against pathogens. The objective of this study was to screen and select bacterial therapeutic candidates from the nasopharynxes of feedlot cattle to mitigate the BRD pathogen Mannheimia haemolytica In a stepwise approach, bacteria (n = 300) isolated from the nasopharynxes of 100 healthy feedlot cattle were identified and initially screened (n = 178 isolates from 12 different genera) for growth inhibition of M. haemolytica Subsequently, selected isolates were evaluated for the ability to adhere to bovine turbinate (BT) cells (n = 47), compete against M. haemolytica for BT cell adherence (n = 15), and modulate gene expression in BT cells (n = 10). Lactobacillus strains had the strongest inhibition of M. haemolytica, with 88% of the isolates (n =33) having inhibition zones ranging from 17 to 23 mm. Adherence to BT cells ranged from 3.4 to 8.0 log10 CFU per 105 BT cells. All the isolates tested in competition assays reduced M. haemolytica adherence to BT cells (32% to 78%). Among 84 bovine genes evaluated, selected isolates upregulated expression of interleukin 8 (IL-8) and IL-6 (P < 0.05). After ranking isolates for greatest inhibition, adhesion, competition, and immunomodulation properties, 6 Lactobacillus strains from 4 different species were selected as the best candidates for further development as intranasal bacterial therapeutics to mitigate M. haemolytica infection in feedlot cattle.IMPORTANCE Bovine respiratory disease (BRD) is a significant animal health issue impacting the beef industry. Current BRD prevention strategies rely mainly on metaphylactic use of antimicrobials when cattle enter feedlots. However, a recent increase in BRD-associated bacterial pathogens that are resistant to metaphylactic antimicrobials highlights a pressing need for the development of novel mitigation strategies. Based upon previous research showing the importance of respiratory commensal bacteria in protecting against bronchopneumonia, this study aimed to develop bacterial therapeutics that could be used to mitigate the BRD pathogen Mannheimia haemolytica Bacteria isolated from the respiratory tracts of healthy cattle were characterized for their inhibitory, adhesive, and immunomodulatory properties. In total, 6 strains were identified as having the best properties for use as intranasal therapeutics to inhibit M. haemolytica If successful in vivo, these strains offer an alternative to metaphylactic antimicrobial use in feedlot cattle for mitigating BRD.
Collapse
Affiliation(s)
- Samat Amat
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
- Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, Alberta, Canada
- Feedlot Health Management Services, Okotoks, Alberta, Canada
| | - Danica Baines
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
| | - Jay Yanke
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
| | - Trevor W Alexander
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, Alberta, Canada
| |
Collapse
|
18
|
Guo Y, McMullen C, Timsit E, Hallewell J, Orsel K, van der Meer F, Yan S, Alexander TW. Genetic relatedness and antimicrobial resistance in respiratory bacteria from beef calves sampled from spring processing to 40 days after feedlot entry. Vet Microbiol 2019; 240:108478. [PMID: 31902491 DOI: 10.1016/j.vetmic.2019.108478] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/20/2019] [Accepted: 10/22/2019] [Indexed: 01/05/2023]
Abstract
Recent studies have shown an increase in antimicrobial-resistant bovine respiratory disease (BRD) pathogens. To investigate the origin of antimicrobial resistance in the respiratory microbiota of beef cattle, three groups (A, B, or C) of 40 calves sourced from different calf-ranches were sampled by deep nasopharyngeal swab (DNS) at the time of first on-ranch vaccination (Time point 1, T1), feedlot entry (Time point 2, T2), and 40 days after feedlot entry (Time point 3, T3; feedlots differed by group). Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni were isolated from DNS samples, tested for antimicrobial susceptibility, and subtyped by pulsed-field gel electrophoresis (PFGE). Antimicrobial resistance genes [tet(H), tet(W), and sul2] were also quantified in DNS metagenomic DNA using PCR. Prevalence of calves positive for BRD pathogens differed among groups and time-points but P. multocida was the most prevalent (61% of calves positive, at least, at one timepoint), followed by M. haemolytica (48%) and H. somni (26%). Most M. haemolytica were susceptible to all antimicrobials (88.6%; n = 70). For P. multocida, the dominant resistance phenotype was against oxytetracycline and neomycin (35.8%). Resistant P. multocida isolates were mainly detected in group C at T3 and had the same PFGE profile. For H. somni, the dominant resistance phenotype was against neomycin (63.3%) and was only observed at T3. The abundance of tet(W) did not change significantly over time (P > 0.05). Abundances of tet(H) and sul2 only increased for group C at T3 (P < 0.05). Overall, this study showed that resistance in the respiratory microbiota of beef calves can increase from calf-ranch to feedlot however, the results can vary by calf-ranch and feedlot.
Collapse
Affiliation(s)
- Yongmei Guo
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada; Inner Mongolia Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, China
| | - Christopher McMullen
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Edouard Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada; Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada
| | | | - Karin Orsel
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Frank van der Meer
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Sumei Yan
- Inner Mongolia Key Laboratory of Animal Nutrition and Feed Science, College of Animal Science, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, China
| | | |
Collapse
|
19
|
Amat S, Holman DB, Timsit E, Schwinghamer T, Alexander TW. Evaluation of the Nasopharyngeal Microbiota in Beef Cattle Transported to a Feedlot, With a Focus on Lactic Acid-Producing Bacteria. Front Microbiol 2019; 10:1988. [PMID: 31551953 PMCID: PMC6743003 DOI: 10.3389/fmicb.2019.01988] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 08/13/2019] [Indexed: 11/13/2022] Open
Abstract
The nasopharyngeal (NP) microbiota is important in defining respiratory health in feedlot cattle, with certain NP commensals potentially protecting against bovine respiratory disease (BRD) pathogens. In the present study, we evaluated longitudinal changes in the NP microbiota with a focus on lactic acid-producing bacteria (LAB) and their linkage with BRD-associated bacteria in steers (n = 13) that were first transported to an auction market, and then to a feedlot. Deep nasopharyngeal swabs were collected at the farm before transportation to the auction market (day 0), at feedlot placement (day 2), and 5 (day 7) and 12 (day 14) days after feedlot placement. Swabs were processed for the assessment of the NP microbiota using 16S rRNA gene sequencing, and for the detection of Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni by culturing. Possible associations among the top 15 most relatively abundant bacterial genera were predicted using a stepwise-selected generalized linear mixed model. Correlations between LAB and BRD-associated Pasteurellaceae families were also assessed. In addition, antimicrobial activity of selected LAB isolates against M. haemolytica was evaluated in vitro. A noticeable shift was observed in the NP microbial community structure, and in the relative abundance of LAB families as a result of auction market exposure, transport and feedlot placement. Varying degrees of positive or negative associations between the 15 most relatively abundant genera were observed. Many of the LAB families were inversely correlated with the BRD-associated Pasteurellaceae family as the cattle were transported to the auction market and then to the feedlot. Nearly all steers were culture-negative for M. haemolytica and H. somni, and P. multocida became less prevalent after feedlot placement. Isolates from the Lactobacillaceae, Streptococcaceae, and Enterococcaceae families inhibited the growth of M. haemolytica. The results of this study indicated that the NP microbiota became more diverse with an increase in microbial richness following transport to an auction market and feedlot. This study provides evidence of potential cooperation and exclusion taking place in the respiratory microbial community of cattle which may be useful for developing microbial-based strategies to mitigate BRD.
Collapse
Affiliation(s)
- Samat Amat
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada.,Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Devin B Holman
- Agriculture and Agri-Food Canada, Lacombe Research and Development Centre, Lacombe, AB, Canada
| | - Edouard Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.,Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada
| | - Timothy Schwinghamer
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| | - Trevor W Alexander
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| |
Collapse
|
20
|
Amat S, Baines D, Timsit E, Hallewell J, Alexander TW. Essential oils inhibit the bovine respiratory pathogens Mannheimia haemolytica, Pasteurella multocida and Histophilus somni and have limited effects on commensal bacteria and turbinate cells in vitro. J Appl Microbiol 2019; 126:1668-1682. [PMID: 30817050 DOI: 10.1111/jam.14238] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/12/2019] [Accepted: 02/25/2019] [Indexed: 11/28/2022]
Abstract
AIMS The objective of this study was to determine antimicrobial activities of essential oils (EOs) against bovine respiratory disease (BRD) pathogens and nasopharyngeal commensal bacteria, as well as cytotoxicity in bovine turbinate (BT) cells in vitro. METHODS AND RESULTS The chemical composition of 16 EOs was determined using gas chromatography-mass spectrometry. All EOs were first evaluated for growth inhibition of a single BRD pathogen Mannheimia haemolytica serotype 1 strain (L024A). The most inhibitory EOs (n = 6) were then tested for antimicrobial activity against multidrug-resistant strains of M. haemolytica (serotypes 1, 2 and 6); the BRD pathogens Pasteurella multocida and Histophilus somni, as well as commensal bacteria that were isolated from the nasopharynx of feedlot cattle. The cytotoxicity of 10 EOs was also evaluated using a BT cell line. The EOs ajowan, thyme and fennel most effectively inhibited all BRD pathogens tested including multidrug-resistant strains with minimum inhibitory concentrations (MIC) of ≤0·025% (volume/volume, v/v). For these EOs, the MIC was 2-32 fold greater against commensal bacteria, compared to BRD-associated pathogens. No cytotoxic effects of EOs against BT cells were observed within the tested range of concentrations (0·0125-0·4%, v/v). CONCLUSIONS The EOs ajowan, thyme and fennel inhibited M. haemolytica, P. multocida and H. somni at a concentration of 0·025% and had minimal antimicrobial activity against nasopharyngeal commensal bacteria and cytotoxicity against BT cells. SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrated that EOs may have potential for intra-nasal administration to mitigate bovine respiratory pathogens in feedlot cattle.
Collapse
Affiliation(s)
- S Amat
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada.,Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - D Baines
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - E Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.,Simpson Ranch Chair in Beef Cattle Health and Wellness, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - J Hallewell
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - T W Alexander
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| |
Collapse
|
21
|
Zhang M, Hill JE, Fernando C, Alexander TW, Timsit E, van der Meer F, Huang Y. Respiratory viruses identified in western Canadian beef cattle by metagenomic sequencing and their association with bovine respiratory disease. Transbound Emerg Dis 2019; 66:1379-1386. [PMID: 30873724 PMCID: PMC7168561 DOI: 10.1111/tbed.13172] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/04/2019] [Accepted: 03/07/2019] [Indexed: 12/23/2022]
Abstract
Bovine respiratory disease (BRD) causes considerable economic losses in North America. The pathogenesis involves interactions between bacteria, viruses, environment and management factors. Primary viral infection can increase the risk of secondary fatal bacterial infection. The objective of this study was to use metagenomic sequencing to characterize the respiratory viromes of paired nasal swabs and tracheal washes from western Canadian feedlot cattle, with or without BRD. A total of 116 cattle (116 nasal swabs and 116 tracheal washes) were analysed. The presence of influenza D virus (IDV), bovine rhinitis A virus (BRAV), bovine rhinitis B virus (BRBV), bovine coronavirus (BCV) and bovine respiratory syncytial virus (BRSV) was associated with BRD. Agreement between identification of viruses in nasal swabs and tracheal washes was generally weak, indicating that sampling location may affect detection of infection. This study reported several viruses for the first time in Canada and provides a basis for further studies investigating candidate viruses important to the prevention of BRD.
Collapse
Affiliation(s)
- Maodong Zhang
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Janet E Hill
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Champika Fernando
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Trevor W Alexander
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| | - Edouard Timsit
- Department of Production Animal Health, University of Calgary, Calgary, AB, Canada.,Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada.,Feedlot Health Management Services, Okotoks, AB, Canada
| | - Frank van der Meer
- Department of Ecosystem and Public Health, University of Calgary, Calgary, AB, Canada
| | - Yanyun Huang
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada.,Prairie Diagnostic Services Inc, Saskatoon, SK, Canada
| |
Collapse
|
22
|
Timsit E, Léguillette R, White BJ, Larson RL, Buczinski S. Likelihood ratios: an intuitive tool for incorporating diagnostic test results into decision-making. J Am Vet Med Assoc 2019; 252:1362-1366. [PMID: 29772968 DOI: 10.2460/javma.252.11.1362] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
23
|
Timsit E, Tison N, Booker CW, Buczinski S. Association of lung lesions measured by thoracic ultrasonography at first diagnosis of bronchopneumonia with relapse rate and growth performance in feedlot cattle. J Vet Intern Med 2019; 33:1540-1546. [PMID: 30901138 PMCID: PMC6524390 DOI: 10.1111/jvim.15483] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 03/06/2019] [Indexed: 11/30/2022] Open
Abstract
Background Severity of lung lesions quantified by thoracic ultrasonography (TUS) at time of bronchopneumonia (BP) diagnosis predicted death among steers not treated for this condition. Further research is needed to confirm that lung lesions detected by TUS can be associated with negative outcomes in cattle with BP that subsequently were treated. Objective To quantify the effects on relapse rate and average daily gain (ADG) of lung lesions detected by TUS at first BP diagnosis in feedlot cattle. Animals Prospective cohort of mixed beef‐breed steers (n = 93; 243 ± 36 kg) and heifers (n = 51; 227 ± 42 kg) with BP at 4 feedlots. Methods Thoracic ultrasonography was performed by the same clinician and 16‐second TUS videos were evaluated offline for maximal depth and area of lung consolidation, maximum number of comet tails, and maximal depth of pleural fluid. Individual ADG was calculated between 1 and 120 days after arrival. Effects of lesions on relapse rate and ADG were investigated using mixed regression models. Results Maximal depth of lung consolidation was associated with a higher risk of relapse (odds ratio [OR], 1.337/cm; 95% confidence interval [CI], 1.042‐1.714) and lower ADG (− 34 g/cm; −64 to −4). Maximal area of lung consolidation also was associated with a higher relapse risk (OR, 1.052/cm2; 1.009‐1.097) but not with ADG. Comet tails and pleural fluid were not associated with risk of relapse or ADG. Conclusions and Clinical Importance Quantifying maximal depth and area of lung consolidation by TUS at first BP diagnosis can provide useful prognostic information in feedlot cattle.
Collapse
Affiliation(s)
- Edouard Timsit
- Department of Production Animal Health, Simpson Ranch Chair in Cattle Health and Wellness, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Feedlot Health Management Services, Okotoks, Alberta, Canada
| | - Nicolas Tison
- Department of Clinical Science, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| | - Calvin W Booker
- Feedlot Health Management Services, Okotoks, Alberta, Canada
| | - Sébastien Buczinski
- Department of Clinical Science, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada
| |
Collapse
|
24
|
McMullen C, Orsel K, Alexander T, van der Meer F, Plastow G, Timsit E. 343 The evolution of the nasopharyngeal bacterial community in beef steer calves from spring processing to 40. J Anim Sci 2018. [DOI: 10.1093/jas/sky404.373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- C McMullen
- Faculty of Veterinary Medicine, University of Calgary,Calgary, MB, Canada
| | - K Orsel
- Faculty of Veterinary Medicine, University of Calgary,Calgary, MB, Canada
| | - T Alexander
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada,Lethbridge, AB, Canada
| | - F van der Meer
- Faculty of Veterinary Medicine, University of Calgary,Calgary, MB, Canada
| | - G Plastow
- Livestock Gentec, Department of Agricultural, Food and Nutritional Science, University of Alberta,Edmonton, AB, Canada
| | - E Timsit
- Faculty of Veterinary Medicine, University of Calgary,Calgary, MB, Canada
| |
Collapse
|
25
|
McMullen C, Orsel K, Alexander TW, van der Meer F, Plastow G, Timsit E. Evolution of the nasopharyngeal bacterial microbiota of beef calves from spring processing to 40 days after feedlot arrival. Vet Microbiol 2018; 225:139-148. [PMID: 30322526 DOI: 10.1016/j.vetmic.2018.09.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 09/07/2018] [Accepted: 09/16/2018] [Indexed: 12/30/2022]
Abstract
The composition of the nasopharyngeal bacterial microbiota has been shown to play a role in cattle respiratory health. However, previous studies are narrow in scope regarding longitudinal observations, limiting our understanding of how respiratory bacteria evolve over time. The objective was therefore to characterize this microbiota and its evolution over time in beef calves. A total of 120 crossbred beef-breed steer calves were enrolled in a study in southern Alberta at the time of first vaccination (spring processing), comprising three groups (40 calves/group) that originated from different ranches and were placed in different feedlots. Deep nasopharyngeal swab samples were collected from the calves at the time of spring processing, arrival at the feedlot, and a targeted 40 days after feedlot arrival. The swabs were processed for DNA extraction and the V4 region of the 16S rRNA gene was sequenced to evaluate the microbiota. The composition of the microbiota differed among groups of calves, with each group showing different relative abundances of 963 observed sequence variants. Mycoplasma was the most abundant genus and M. dispar the most abundant species across all groups. There was a distinct shift in the composition of the microbiota over time for all calf groups; however, changes in sequence variants differed by group. Variations in both microbiota composition and temporal changes of sequence variants according to calf group indicates that the respiratory microbiota of beef cattle may lack a common pattern of evolution from ranch to feedlot, and that future studies should account for potential group effects.
Collapse
Affiliation(s)
| | - Karin Orsel
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Trevor W Alexander
- Lethbridge Research and Development Center, Agriculture and Agri-food Canada, Lethbridge, AB, Canada
| | - Frank van der Meer
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Graham Plastow
- Livestock Gentec, University of Alberta, Edmonton, AB, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada; Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada; Feedlot Health Management Services, Okotoks, AB, Canada.
| |
Collapse
|
26
|
Buczinski S, Buathier C, Bélanger AM, Michaux H, Tison N, Timsit E. Inter-rater agreement and reliability of thoracic ultrasonographic findings in feedlot calves, with or without naturally occurring bronchopneumonia. J Vet Intern Med 2018; 32:1787-1792. [PMID: 30133838 PMCID: PMC6189347 DOI: 10.1111/jvim.15257] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 04/26/2018] [Accepted: 06/07/2018] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Thoracic ultrasonography (TUS) can be used to assess the extent and severity of lung lesions associated with bronchopneumonia (BP) in feedlot cattle. HYPOTHESIS/OBJECTIVES To assess inter-rater agreement and reliability of TUS findings in feedlot cattle, with or without naturally occurring BP. ANIMALS Feedlot steers with (n = 210) or without (n = 107) clinical signs of BP that were assessed by TUS in a previous case-control study. METHODS A random sample of 50 TUS videos (16-s duration) were scored by 6 raters with various levels of TUS expertise. Lung consolidation, comet tail artifacts, pleural irregularity and effusion were scored. Inter-rater agreement was assessed using raw percentage of agreement (Pa), Cohen's and Fleiss' Kappa (κ), and Gwet agreement coefficient (AC1). Intra-class correlation (ICC) was determined for variables with continuous measurements (mixed factorial design). RESULTS Median (interquartile range [IQR]) Pa were 0.84 (0.80-0.89), 0.82 (0.80-0.87), 0.62 (0.53-0.67), and 0.82 (0.75-0.86) for presence of lung consolidation, comet tails, pleural irregularity, and pleural effusion, respectively. For the same lesions, Fleiss κ (95% confidence intervals [CI]) were 0.67 (0.49-0.86), 0.56 (0.33-0.80), 0.20 (-0.05 to 0.44), and 0.36 (0.10-0.61), respectively. AC1 were 0.68 (0.51-0.86), 0.73 (0.58-0.89), 0.21 (-0.01 to 0.44), and 0.71 (0.51-0.92), respectively. Moderate reliability was found among raters for all quantitative variables (ICC ranged from 0.52 to 0.70). CONCLUSIONS AND CLINICAL IMPORTANCE Inter-rater agreement was good for presence of lung consolidation, comet tails and pleural effusion (based on Pa and AC1) but was slight to poor for pleural irregularity.
Collapse
Affiliation(s)
- S Buczinski
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - C Buathier
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - A M Bélanger
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - H Michaux
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - N Tison
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - E Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada
| |
Collapse
|
27
|
Stroebel C, Alexander T, Workentine ML, Timsit E. Effects of transportation to and co-mingling at an auction market on nasopharyngeal and tracheal bacterial communities of recently weaned beef cattle. Vet Microbiol 2018; 223:126-133. [PMID: 30173738 DOI: 10.1016/j.vetmic.2018.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/03/2018] [Accepted: 08/03/2018] [Indexed: 12/13/2022]
Abstract
The objective was to study effects of transportation to and co-mingling at an auction market on nasopharyngeal and tracheal bacterial communities of feedlot cattle. Two groups of 30 Angus-cross heifers were studied from weaning to 28 d after arrival at a feedlot. For each group, half the heifers were either transported directly to a feedlot after weaning (RANC) or transported to and co-mingled at an auction market for 24 h before being placed in a feedlot (AUCT). Deep nasal swabs (DNS) and trans-tracheal aspirates (TTA) were collected at weaning (d0) and at on-arrival processing at the feedlot (d2). At 7 (d9) and 28 d (d30) after arrival, DNS were repeated. The DNA was extracted from DNS and TTA and the V4 region of the 16S rRNA gene sequenced (MiSeq). Alpha diversity analysis did not reveal differences between AUCT and RANC. However, bacterial diversity decreased over time in the nasopharynx, especially at d9. Although beta-diversity was not different between AUCT and RANC, interval after arrival and feedlot where heifers were placed affected composition of the nasopharyngeal bacterial communities. In both groups, a large increase in Mycoplasma was observed after arrival; in one group, Mycoplasma bovis was dominant at d9 and remained dominant until d30. However, in the other group, Mycoplasma dispar dominated at d9 and was replaced by Moraxella at d30. We concluded that transportation to and co-mingling at an auction market for 24 h did not significantly influence diversity or composition of nasopharyngeal or tracheal bacterial communities.
Collapse
Affiliation(s)
- Christina Stroebel
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Trevor Alexander
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada.
| | | | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada; Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada; Feedlot Health Management Services, Okotoks, AB, Canada.
| |
Collapse
|
28
|
Bhatt K, Timsit E, Rawlyk N, Potter A, Liljebjelke K. Integrative Conjugative Element ICE Hs1 Encodes for Antimicrobial Resistance and Metal Tolerance in Histophilus somni. Front Vet Sci 2018; 5:153. [PMID: 30042951 PMCID: PMC6048870 DOI: 10.3389/fvets.2018.00153] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 06/18/2018] [Indexed: 12/21/2022] Open
Abstract
The objectives of this study were to determine antimicrobial resistance and metal tolerance, and identify associated genes and mobile genetic elements in clinical strains of Histophilus somni isolated from feedlot cattle in Alberta during years 2012-2016 (contemporary isolates, n = 63) and years 1980-1990 (historical isolates, n = 31). Comparison of antimicrobial resistance (AMR) showed a significant increase in resistance among contemporary isolates compared to historical isolates (P < 0.001). Tolerance to copper (Cu) and zinc (Zn) concentrations above 1 mM was observed in 68 and 52% of the contemporary isolates, respectively. The tet(H) gene associated with oxytetracycline resistance and multicopper oxidase (mco) and cation efflux (czcD) genes associated with Cu and Zn tolerance were identified. An integrative conjugative element; ICEHs1, was identified in whole genome sequences of strains resistant to oxytetracycline, which had Cu and Zn minimum inhibitory concentrations (MIC) >1 mM. The length of ICEHs1 was 64,932 bp and it contained 83 genes, including tetracycline resistance gene tetH, a multidrug efflux pump gene ebrB, and metal tolerance genes mco, czcD, and acr3. Comparative genomics of ICEs revealed that ICEHs1 shares high homology with previously described ICEs of Histophilus somni, Pasteurella multocida, and Mannheimia haemolytica. The ICEHs1 is an active element capable of intra- and inter-genus transfer as demonstrated by successful transfer to H. somni and P. multocida recipients. All isolates carrying ICEHs1 were resistant to tetracycline, a commonly used antibiotic in feedlots, and had Cu and Zn MIC higher than 1 mM. Since Cu and Zn are routinely used in feedlots, there is the possibility of co-selection of AMR in H. somni due to selection pressure created by Cu and Zn. Based on results of in-vitro conjugation experiments, ICEHs1 mediated transmission of antimicrobial and metal resistance genes is possible between BRD pathogens in the respiratory tract, potentially undermining treatment options available for histophilosis and BRD.
Collapse
Affiliation(s)
- Krishna Bhatt
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Neil Rawlyk
- Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Andrew Potter
- Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Karen Liljebjelke
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
29
|
Timsit E, Workentine M, van der Meer F, Alexander T. Distinct bacterial metacommunities inhabit the upper and lower respiratory tracts of healthy feedlot cattle and those diagnosed with bronchopneumonia. Vet Microbiol 2018; 221:105-113. [PMID: 29981695 DOI: 10.1016/j.vetmic.2018.06.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/05/2018] [Accepted: 06/07/2018] [Indexed: 12/30/2022]
Abstract
Specific nasopharyngeal bacterial communities can provide colonization resistance against respiratory pathogens in cattle. However, the role of bacterial communities of the lower airways in respiratory health remains largely unknown. Therefore, our objective was to compare nasopharyngeal and tracheal bacterial communities between healthy feedlot cattle and those with bronchopneumonia (BP). Deep nasal swabs and trans-tracheal aspiration samples were collected from steers with (n = 60) and without (n = 60) BP at 4 feedlots in Western Canada. After DNA extraction, 16S rRNA gene (V4) was amplified and sequenced. Alpha-diversity analysis revealed a lower bacterial diversity in the nasopharynx and trachea of steers with BP compared to healthy pen-mates. Bacterial communities present within the airways clustered into 4 distinct metacommunities that were associated with sampling locations and health status. Metacommunity 1, enriched with Mycoplasma bovis, Mannheimia haemolytica and Pasteurella multocida, was dominant in the nasopharynx and trachea of steers with BP. In contrast, metacommunity 3, enriched with Mycoplasma dispar, Lactococcus lactis and Lactobacillus casei, was mostly present in the trachea of healthy steers. Metacommunity 4, enriched with Corynebacterium, Jeotgalicoccus, Psychrobacter and Planomicrobium, was present in the nasopharynx only. Metacommunity 2, enriched with Histophilus somni, Moraxella and L. lactis, was present in both healthy and sick steers, but was primarily detected in one feedlot. We concluded that distinct bacterial metacommunities inhabited the nasopharynx and trachea of healthy feedlot cattle and those with BP. Because L. lactis and L. casei can inhibit M. haemolytica growth in vitro, their presence in healthy steers may have provided colonization resistance against bacterial respiratory pathogens.
Collapse
Affiliation(s)
- Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada; Simpson Ranch Chair in Beef Cattle Health and Wellness, University of Calgary, Calgary, AB, Canada; Feedlot Health Management Services, Okotoks, AB, Canada.
| | - Matthew Workentine
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Frank van der Meer
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Trevor Alexander
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada.
| |
Collapse
|
30
|
Bond SL, Timsit E, Workentine M, Alexander T, Léguillette R. Upper and lower respiratory tract microbiota in horses: bacterial communities associated with health and mild asthma (inflammatory airway disease) and effects of dexamethasone. BMC Microbiol 2017; 17:184. [PMID: 28835202 PMCID: PMC5569571 DOI: 10.1186/s12866-017-1092-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 08/14/2017] [Indexed: 01/04/2023] Open
Abstract
Background The microbial composition of the equine respiratory tract, and differences due to mild equine asthma (also called Inflammatory Airway Disease (IAD)) have not been reported. The primary treatment for control of IAD in horses are corticosteroids. The objectives were to characterize the upper and lower respiratory tract microbiota associated with respiratory health and IAD, and to investigate the effects of dexamethasone on these bacterial communities using high throughput sequencing. Results The respiratory microbiota of horses was dominated by four major phyla, Proteobacteria (43.85%), Actinobacteria (21.63%), Firmicutes (16.82%), and Bacteroidetes (13.24%). Fifty genera had a relative abundance > 0.1%, with Sphingomonas and Pantoea being the most abundant. The upper and lower respiratory tract microbiota differed in healthy horses, with a decrease in richness in the lower airways, and 2 OTUs that differed in abundance. There was a separation between bacterial communities in the lower respiratory tract of healthy and IAD horses; 6 OTUs in the tracheal community had different abundance with disease status, with Streptococcus being increased in IAD horses. Treatment with dexamethasone had an effect on the lower respiratory tract microbiota of both heathy and IAD horses, with 8 OTUs increasing in abundance (including Streptococcus) and 1 OTU decreasing. Conclusions The lower respiratory tract microbiota differed between healthy and IAD horses. Further research on the role of Streptococcus in IAD is warranted. Dexamethasone treatment affected the lower respiratory tract microbiota, which suggests that control of bacterial overgrowth in IAD horses treated with dexamethasone could be part of the treatment strategy. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1092-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Stephanie L Bond
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
| | - Matthew Workentine
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Trevor Alexander
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - Renaud Léguillette
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
| |
Collapse
|
31
|
Amat S, Subramanian S, Timsit E, Alexander TW. Probiotic bacteria inhibit the bovine respiratory pathogen Mannheimia haemolytica serotype 1 in vitro. Lett Appl Microbiol 2017; 64:343-349. [PMID: 28178767 DOI: 10.1111/lam.12723] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 01/19/2017] [Accepted: 02/03/2017] [Indexed: 01/03/2023]
Abstract
This study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The inhibitory effects of nine probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus helveticus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, Streptococcus thermophilus and two Paenibacillus polymyxa strains) against M. haemolytica were evaluated using a spot-on-lawn method. Probiotic strains were then tested for their adherence to bovine bronchial epithelial (BBE) cells and the ability to displace and compete against M. haemolytica on BBE. Except for S. thermophilus, all probiotic strains inhibited the growth of M. haemolytica, with zones of inhibition ranging between 12 and 19 mm. Lactobacillus strains and Lactococcus lactis displayed greater (P < 0·05) BBE adhesion compared with M. heamolytica (8·3%) and other probiotics (<2·2%). Strains of P. polymyxa and L. acidophilus caused the greatest reduction in M. haemolytica adherence, through both displacement and competition, compared with other probiotics. The results of this study suggest that probiotics may have the potential to colonize the bovine respiratory tract, and exert antagonistic effects against M. haemolytica serotype 1. SIGNIFICANCE AND IMPACT OF THE STUDY A common method to control bovine respiratory disease (BRD) in feedlots is through mass medication with antibiotics upon cattle entry (i.e. metaphylaxis). Increasingly, antimicrobial resistance in BRD bacterial pathogens has been observed in feedlots, which may have important implications for cattle health. In this study, probiotic strains were shown to adhere to bovine respiratory cells and inhibit the BRD pathogen M. haemolytica serotype 1 through competition and displacement. Probiotics may therefore offer a mitigation strategy to reduce BRD bacterial pathogens, in place of metaphylactic antimicrobials.
Collapse
Affiliation(s)
- S Amat
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - S Subramanian
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - E Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - T W Alexander
- Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| |
Collapse
|
32
|
Windeyer MC, Timsit E, Barkema H. Bovine respiratory disease in pre-weaned dairy calves: Are current preventative strategies good enough? Vet J 2017; 224:16-17. [DOI: 10.1016/j.tvjl.2017.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022]
|
33
|
Holman DB, Timsit E, Amat S, Abbott DW, Buret AG, Alexander TW. Erratum to: The nasopharyngeal microbiota of beef cattle before and after transport to a feedlot. BMC Microbiol 2017; 17:95. [PMID: 28427328 PMCID: PMC5399422 DOI: 10.1186/s12866-017-1007-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 04/11/2017] [Indexed: 11/18/2022] Open
Affiliation(s)
- Devin B Holman
- United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, Ames, USA
| | - Edouard Timsit
- Department of Production Animal Health, University of Calgary, Calgary, Canada
| | - Samat Amat
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - D Wade Abbott
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - Andre G Buret
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Trevor W Alexander
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada.
| |
Collapse
|
34
|
Holman DB, Timsit E, Amat S, Abbott DW, Buret AG, Alexander TW. The nasopharyngeal microbiota of beef cattle before and after transport to a feedlot. BMC Microbiol 2017; 17:70. [PMID: 28330466 PMCID: PMC5361731 DOI: 10.1186/s12866-017-0978-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 03/11/2017] [Indexed: 12/17/2022] Open
Abstract
Background The nasopharyngeal (NP) microbiota plays an important role in bovine health, comprising a rich and diverse microbial community. The nasopharynx is also the niche for potentially pathogenic agents which are associated with bovine respiratory disease (BRD), a serious and costly illness in feedlot cattle. We used 14 beef heifers from a closed and disease-free herd to assess the dynamics of the NP microbiota of cattle that are transported to a feedlot. Cattle were sampled prior to transport to the feedlot (day 0) and at days 2, 7, and 14. Results The structure of the NP microbiota changed significantly over the course of the study, with the largest shift occurring between day 0 (prior to transport) and day 2 (P < 0.001). Phylogenetic diversity and richness increased following feedlot placement (day 2; P < 0.05). The genera Pasteurella, Bacillus, and Proteus were enriched at day 0, Streptococcus and Acinetobacter at day 2, Bifidobacterium at day 7, and Mycoplasma at day 14. The functional potential of the NP microbiota was assessed using PICRUSt, revealing that replication and repair, as well as translation pathways, were more relatively abundant in day 14 samples. These differences were driven mostly by Mycoplasma. Although eight cattle were culture-positive for the BRD-associated bacterium Pasteurella multocida at one or more sampling times, none were culture-positive for Mannheimia haemolytica or Histophilus somni. Conclusions This study investigated the effect that feedlot placement has on the NP microbiota of beef cattle over a 14-d period. Within two days of transport to the feedlot, the NP microbiota changed significantly, increasing in both phylogenetic diversity and richness. These results demonstrate that there is an abrupt shift in the NP microbiota of cattle after transportation to a feedlot. This may have importance for understanding why cattle are most susceptible to BRD after feedlot placement. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-0978-6) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Devin B Holman
- United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, Ames, IA, USA
| | - Edouard Timsit
- Department of Production Animal Health, University of Calgary, Calgary, AB, Canada
| | - Samat Amat
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| | - D Wade Abbott
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| | - Andre G Buret
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Trevor W Alexander
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB, T1J 4B1, Canada.
| |
Collapse
|
35
|
Timsit E, Workentine M, Crepieux T, Miller C, Regev-Shoshani G, Schaefer A, Alexander T. Effects of nasal instillation of a nitric oxide-releasing solution or parenteral administration of tilmicosin on the nasopharyngeal microbiota of beef feedlot cattle at high-risk of developing respiratory tract disease. Res Vet Sci 2017; 115:117-124. [PMID: 28231472 DOI: 10.1016/j.rvsc.2017.02.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 01/28/2017] [Accepted: 02/02/2017] [Indexed: 12/20/2022]
Abstract
Nitric oxide has bactericidal and virucidal properties. Nasal instillation of a nitric oxide releasing solution (NORS) on arrival at the feedlot was recently reported as inferior to a parenteral injection of tilmicosin (macrolide antibiotic) for control of bovine respiratory disease (BRD) in cattle at high-risk of developing BRD. We hypothesized that this inferiority was due to differences between treatments with regards to their effects on the nasopharyngeal microbiota. The objective was to compare nasal instillation of NORS versus parenteral administration of tilmicosin regarding their effects on the nasopharyngeal microbiota of feedlot cattle at high-risk of developing BRD. Culture-independent community profiling (16S rRNA sequencing) and culture-based methods were used to evaluate treatment effects. High-risk Angus-cross heifers (n=20) were randomly allocated to 2 treatment groups on arrival at a feedlot and received either NORS or tilmicosin for prevention of BRD. Heifers were sampled using guarded deep nasal swabs immediately prior to treatment (day 0) and on days 1, 5 and 10 after treatment. Based on culture-independent community profiling, there was a distinct shift in composition of the nasopharyngeal microbiota during the first 10 d after arrival, with 116 OTUs changing over time, but no difference between treatment groups. However, culture-based methods detected a difference between treatment groups, with more cattle culture-positive for Pasteurellaceae in the NORS group at day 5 post-treatment. This difference in ability to inhibit colonization of the nasopharynx by Pasteurellaceae may be the basis for NORS being inferior to tilmicosin for control of BRD in high-risk cattle.
Collapse
Affiliation(s)
- E Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
| | - M Workentine
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - T Crepieux
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - C Miller
- Faculty of Medicine, Respiratory Division, University of British Columbia, Vancouver, BC, Canada; Bovicor Pharmatech Inc., Vancouver, BC, Canada
| | - G Regev-Shoshani
- Faculty of Medicine, Respiratory Division, University of British Columbia, Vancouver, BC, Canada; Bovicor Pharmatech Inc., Vancouver, BC, Canada
| | - A Schaefer
- Department of Agricultural, Food and Nutritional Science (AFNS), University of Alberta, Edmonton, AB, Canada
| | - T Alexander
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| |
Collapse
|
36
|
Timsit E, Dendukuri N, Schiller I, Buczinski S. Diagnostic accuracy of clinical illness for bovine respiratory disease (BRD) diagnosis in beef cattle placed in feedlots: A systematic literature review and hierarchical Bayesian latent-class meta-analysis. Prev Vet Med 2016; 135:67-73. [DOI: 10.1016/j.prevetmed.2016.11.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 11/04/2016] [Accepted: 11/07/2016] [Indexed: 10/20/2022]
|
37
|
Amat S, Timsit E, Holman DB, Alexander TW. 0472 Characterization of bovine nasopharyngeal lactic acid bacteria and their in vitro antimicrobial activities against the respiratory pathogen Mannheimia haemolytica. J Anim Sci 2016. [DOI: 10.2527/jam2016-0472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
38
|
Wolfger B, Mang AV, Cook N, Orsel K, Timsit E. Technical note: Evaluation of a system for monitoring individual feeding behavior and activity in beef cattle. J Anim Sci 2016; 93:4110-4. [PMID: 26440190 DOI: 10.2527/jas.2015-8947] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Behavioral observations are important to detect illness in beef cattle. However, traditional observation techniques are time and labor intensive and may be subjective. The objective was to validate a system for monitoring individual feeding behavior and activity in beef cattle (Fedometer [FEDO]; ENGS, Rosh Pina, Israel). Sixteen steers (initial BW ± SD = 326 ± 46 kg) were fitted with data loggers (FEDO) on their left front leg and housed in a pen with a feedbunk equipped with an antenna emitting an electromagnetic field that reached 30 ± 2 cm in front of the feedbunk. Feedbunk attendance (duration of visit and frequency of meals) measured by FEDO was compared with live observations (27 observational periods lasting between 72 and 240 min; mean 126 min). Lying time and frequency of lying bouts were compared with previously validated accelerometers fitted to the hind leg (10 steers equipped for 10 to 12 d; HOBO Pendant G Acceleration Data Logger [HOBO]; Onset Computer Corporation, Pocasset, MA). Step counts were compared with video recordings (15 observations for 6-min intervals in 6 steers). Concordance correlation coefficients (CCC), accounting for repeated measures, and limits of agreement were computed. Comparison between FEDO and observed time at the feedbunk yielded a CCC of 0.98 (95% confidence interval [CI] 0.97-0.99). All 68 meal events observed were recorded by FEDO. However, FEDO recorded 4 meal events during the 27 observational periods that were not observed. Lying time measured by HOBO and FEDO were highly correlated (CCC = 0.98; 95% CI 0.97-0.99). However, frequency of lying bouts measured by FEDO was only moderately correlated to HOBO (CCC = 0.71; 95% CI 0.63-0.77); FEDO underestimating the number of lying bouts (on average, 0.4 fewer bouts per 6 h). Step count by FEDO was moderately correlated to video observations (CCC = 0.75; 95% CI 0.49-0.89); FEDO overestimating the number of steps (on average, 5 more steps per 6 min). In conclusion, the FEDO system accurately measured duration of feedbunk attendance, frequency of meals, and lying time. However, it overestimated the number of steps and underestimated the frequency of lying bouts.
Collapse
|
39
|
Buczinski S, Ménard J, Timsit E. Incremental Value (Bayesian Framework) of Thoracic Ultrasonography over Thoracic Auscultation for Diagnosis of Bronchopneumonia in Preweaned Dairy Calves. J Vet Intern Med 2016; 30:1396-401. [PMID: 27305277 PMCID: PMC5094515 DOI: 10.1111/jvim.14361] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/06/2016] [Accepted: 05/17/2016] [Indexed: 11/26/2022] Open
Abstract
Background Thoracic ultrasonography (TUS) is a specific and relatively sensitive method to diagnose bronchopneumonia (BP) in dairy calves. Unfortunately, as it requires specific training and equipment, veterinarians typically base their diagnosis on thoracic auscultation (AUSC), which is rapid and easy to perform. Hypothesis/Objectives We hypothesized that the use of TUS, in addition to AUSC, can significantly increase accuracy of BP diagnosis. Therefore, the objectives were to (i) determine the incremental value of TUS over AUSC for diagnosis of BP in preweaned dairy calves and (ii) assess diagnostic accuracy of AUSC. Animals Two hundred and nine dairy calves (<1 month of age) were enrolled in this cross‐sectional study. Methods Prospective cross‐sectional study. All calves from a veal calves unit were examined (independent operators) using the Wisconsin Calf Respiratory Scoring Criteria (CRSC), AUSC, and TUS. A Bayesian latent class approach was used to estimate the incremental value of AUSC over TUS (integrated discrimination improvement [IDI]) and the diagnostic accuracy of AUSC. Results Abnormal CRSC, AUSC, and TUS were recorded in 3.3, 53.1, and 23.9% of calves, respectively. AUSC was sensitive (72.9%; 95% Bayesian credible interval [BCI]: 50.1–96.4%), but not specific (53.3%; 95% BCI: 43.3–64.0%) to diagnose BP. Compared to AUSC, TUS was more specific (92.9%; 95% BCI: 86.5–97.1%), but had similar sensitivity (76.5%; 95% BCI: 60.2–88.8%). The incremental value of TUS over AUSC was high (IDI = 43.7%; 5% BCI: 22.0–63.0%) significantly improving proportions of sick and healthy calves appropriately classified. Conclusions and Clinical Importance The use of TUS over AUSC significantly improved accuracy of BP diagnosis in dairy calves.
Collapse
Affiliation(s)
- S Buczinski
- Department of Clinical Science, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC, Canada
| | - J Ménard
- Department of Clinical Science, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC, Canada
| | - E Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
40
|
Affiliation(s)
- Edouard Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Devin B. Holman
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| | - Jennyka Hallewell
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| | - Trevor W. Alexander
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB, T1J 4B1, Canada
| |
Collapse
|
41
|
Crepieux T, Miller C, Regev-Shoshani G, Schaefer A, Dorin C, Alexander T, Timsit E. Randomized, non-inferiority trial comparing a nitric oxide releasing solution with a macrolide antibiotic for control of bovine respiratory disease in beef feedlot calves at high-risk of developing respiratory tract disease. Res Vet Sci 2016; 105:216-21. [DOI: 10.1016/j.rvsc.2016.02.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 02/08/2016] [Accepted: 02/21/2016] [Indexed: 10/22/2022]
|
42
|
Timsit E, Workentine M, Schryvers AB, Holman DB, van der Meer F, Alexander TW. Evolution of the nasopharyngeal microbiota of beef cattle from weaning to 40 days after arrival at a feedlot. Vet Microbiol 2016; 187:75-81. [PMID: 27066712 DOI: 10.1016/j.vetmic.2016.03.020] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 03/15/2016] [Accepted: 03/25/2016] [Indexed: 11/15/2022]
Abstract
Bovine respiratory disease complex (BRDc) is a major cause of morbidity and mortality in beef cattle. There is recent evidence suggesting that the nasopharyngeal microbiota has a key role in respiratory health and disease susceptibility in cattle. However, there is a paucity of knowledge regarding evolution of the nasopharyngeal microbiota when cattle are most likely to develop BRDc (i.e., from weaning to 40days after arrival at a feedlot). The objective was to describe the evolution of the nasopharyngeal microbiota of beef cattle from weaning to 40days after arrival at a feedlot. Deep nasal swabs (DNS) from 30 Angus-cross steers were collected at weaning, on arrival at a feedlot, and at day 40 after arrival. The DNA was extracted from DNS and the hypervariable region V3 of the 16S rRNA gene was amplified and sequenced (Illumina MiSeq platform). Nasopharyngeal microbiota underwent a profound evolution from weaning to arrival at the feedlot and from arrival to day 40, with the abundance of 92 Operational Taxonomic Units (OTUs) significantly changing over time. Mycoplasma (M. dispar and M. bovirhinis) was the most abundant genus in the nasopharynx, accounting for 53% of the total bacterial population. Because an evolving bacterial community may be less capable of resisting colonization by pathogenic bacteria, the instability of the nasopharyngeal microbiota documented in this study might explain why cattle are most likely to be affected with BRDc during the first weeks after weaning and arrival at a feedlot.
Collapse
Affiliation(s)
- Edouard Timsit
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
| | - Matthew Workentine
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Anthony B Schryvers
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada; Faculty of Medicine, University of Calgary, Calgary, AB, Canada
| | - Devin B Holman
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - Frank van der Meer
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Trevor W Alexander
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| |
Collapse
|
43
|
Wolfger B, Timsit E, White BJ, Orsel K. A Systematic Review of Bovine Respiratory Disease Diagnosis Focused on Diagnostic Confirmation, Early Detection, and Prediction of Unfavorable Outcomes in Feedlot Cattle. Vet Clin North Am Food Anim Pract 2015. [DOI: 10.1016/j.cvfa.2015.05.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
44
|
Mang AV, Buczinski S, Booker CW, Timsit E. Evaluation of a Computer-aided Lung Auscultation System for Diagnosis of Bovine Respiratory Disease in Feedlot Cattle. J Vet Intern Med 2015; 29:1112-6. [PMID: 26059327 PMCID: PMC4895372 DOI: 10.1111/jvim.12657] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 03/04/2015] [Accepted: 04/16/2015] [Indexed: 11/28/2022] Open
Abstract
Background A computer‐aided lung auscultation (CALA) system was recently developed to diagnose bovine respiratory disease (BRD) in feedlot cattle. Objectives To determine, in a case–control study, the level of agreement between CALA and veterinary lung auscultation and to evaluate the sensitivity (Se) and specificity (Sp) of CALA to diagnose BRD in feedlot cattle. Animals A total of 561 Angus cross‐steers (initial body weight = 246 ± 45 kg) were observed during the first 50 day after entry to a feedlot. Methods Case–control study. Steers with visual signs of BRD identified by pen checkers were examined by a veterinarian, including lung auscultation using a conventional stethoscope and CALA that produced a lung score from 1 (normal) to 5 (chronic). For each steer examined for BRD, 1 apparently healthy steer was selected as control and similarly examined. Agreement between CALA and veterinary auscultation was assessed by kappa statistic. CALA's Se and Sp were estimated using Bayesian latent class analysis. Results Of the 561 steers, 35 were identified with visual signs of BRD and 35 were selected as controls. Comparison of veterinary auscultation and CALA (using a CALA score ≥2 as a cut off) revealed a substantial agreement (kappa = 0.77). Using latent class analysis, CALA had a relatively high Se (92.9%; 95% credible interval [CI] = 0.71–0.99) and Sp (89.6%; 95% CI = 0.64–0.99) for diagnosing BRD compared with pen checking. Conclusions CALA had good diagnostic accuracy (albeit with a relatively wide CI). Its use in feedlots could increase the proportion of cattle accurately diagnosed with BRD.
Collapse
Affiliation(s)
- A V Mang
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - S Buczinski
- Department of Clinical Science, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC, Canada
| | - C W Booker
- Feedlot Health Management Services, Okotoks, AB, Canada
| | - E Timsit
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.,Feedlot Health Management Services, Okotoks, AB, Canada
| |
Collapse
|
45
|
Wolfger B, Timsit E, Pajor EA, Cook N, Barkema HW, Orsel K. Technical note: Accuracy of an ear tag-attached accelerometer to monitor rumination and feeding behavior in feedlot cattle1. J Anim Sci 2015; 93:3164-8. [DOI: 10.2527/jas.2014-8802] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
46
|
Timsit E, Christensen H, Bareille N, Seegers H, Bisgaard M, Assié S. Transmission dynamics of Mannheimia haemolytica in newly-received beef bulls at fattening operations. Vet Microbiol 2013; 161:295-304. [DOI: 10.1016/j.vetmic.2012.07.044] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 07/27/2012] [Accepted: 07/29/2012] [Indexed: 11/26/2022]
|
47
|
Timsit E, Arcangioli MA, Bareille N, Seegers H, Assié S. Transmission dynamics of Mycoplasma bovis in newly received beef bulls at fattening operations. J Vet Diagn Invest 2012; 24:1172-6. [DOI: 10.1177/1040638712463211] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Mycoplasma bovis is an important cause of bovine respiratory disease (BRD) in newly received cattle at fattening operations. However, little information on its within-pen transmission dynamics during a BRD outbreak is available. Such information is nevertheless crucial to adapt control measures during M. bovis–associated BRD outbreaks. The objective of the current study was to determine whether single or multiple clones of M. bovis are present within a pen during a BRD outbreak that occurs early in the feeding period. Sixteen BRD outbreaks that naturally occurred in 12 pens of 8–12 bulls each ( n = 112) newly received at 3 fattening operations were investigated. Two hundred and thirty-nine transtracheal aspirations (TTA) were performed during the outbreaks, and the M. bovis isolates obtained were characterized by pulsed-field gel electrophoresis (PFGE). Mycoplasma bovis isolates were recovered from TTA in 8 of the 16 BRD outbreaks that occurred. The within-pen prevalence of bulls positive for M. bovis during these outbreaks ranged from 8% to 100%. The PFGE analysis revealed that, even though bulls came from multiple origins, a single clone of M. bovis was present within a pen during BRD outbreaks with a high prevalence of M. bovis infection. The study therefore indicates that, even if M. bovis can recrudesce from carriers after stressful events such as transportation and commingling, the increased prevalence of M. bovis pulmonary infection observed during BRD outbreaks that are early occurring in the feeding period seems primarily due to the horizontal transmission of only 1 clone among cattle.
Collapse
Affiliation(s)
- Edouard Timsit
- UMR1300 BioEpAR, LUNAM, Oniris and INRA, Nantes, France (Timsit, Bareille, Seegers, Assié)
- UMR Mycoplasmoses des Ruminants, Université de Lyon, VetAgro Sup and Anses, Marcy l’Etoile, France (Arcangioli)
| | - Marie-Anne Arcangioli
- UMR1300 BioEpAR, LUNAM, Oniris and INRA, Nantes, France (Timsit, Bareille, Seegers, Assié)
- UMR Mycoplasmoses des Ruminants, Université de Lyon, VetAgro Sup and Anses, Marcy l’Etoile, France (Arcangioli)
| | - Nathalie Bareille
- UMR1300 BioEpAR, LUNAM, Oniris and INRA, Nantes, France (Timsit, Bareille, Seegers, Assié)
- UMR Mycoplasmoses des Ruminants, Université de Lyon, VetAgro Sup and Anses, Marcy l’Etoile, France (Arcangioli)
| | - Henri Seegers
- UMR1300 BioEpAR, LUNAM, Oniris and INRA, Nantes, France (Timsit, Bareille, Seegers, Assié)
- UMR Mycoplasmoses des Ruminants, Université de Lyon, VetAgro Sup and Anses, Marcy l’Etoile, France (Arcangioli)
| | - Sébastien Assié
- UMR1300 BioEpAR, LUNAM, Oniris and INRA, Nantes, France (Timsit, Bareille, Seegers, Assié)
- UMR Mycoplasmoses des Ruminants, Université de Lyon, VetAgro Sup and Anses, Marcy l’Etoile, France (Arcangioli)
| |
Collapse
|
48
|
Timsit E, Bareille N, Seegers H, Lehebel A, Assié S. Visually undetected fever episodes in newly received beef bulls at a fattening operation: occurrence, duration, and impact on performance. J Anim Sci 2011; 89:4272-80. [PMID: 21788432 DOI: 10.2527/jas.2011-3892] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Monitoring body temperature of newly received cattle allows for identification of fever episodes not visually detected by feedlot personnel (FENO). Information concerning the occurrence, duration, and impact on performance of these FENO is not available in the literature. Such information is crucial to assess the potential benefit of the identification and treatment of FENO. Therefore, the objectives of this study were to describe the occurrence and duration of FENO and to evaluate their impact on ADG. One hundred twelve beef bulls (initial BW = 346 ± 36 kg) were studied for 40 d after arrival at 3 French fattening operations. At d 1, each animal was administered orally a reticulo-rumen bolus, which allowed continuous measurement and recording of reticulo-rumen temperature. Animals were weighed on d 1 and 40. Bulls were observed twice daily by personnel for visual signs of apparent disease. Bulls that appeared ill, had a rectal temperature ≥39.7°C, and demonstrated symptoms consistent with bovine respiratory disease (BRD) were treated with antibiotics. After d 40, data obtained from the boluses were retrospectively analyzed using a cumulative sum test to detect significant increases in reticulo-rumen temperature considered as fever episodes. Numerous fever episodes (n = 449) were retrospectively detected in 110 bulls. Of these 449 fever episodes, 74% were not associated with any visually detected clinical signs of disease and thus were identified as FENO. These FENO were often transitory (75% lasted less than 47 h). However, 25% lasted from 47 to 263 h. Of the 112 bulls, 88 were treated for BRD with 20 and 7 animals treated, respectively, 2 and 3 times. In treated animals, fever episodes began 4 to 177 h (mean = 50 h) before BRD treatment. The duration of FENO was associated (P = 0.002) with a lesser ADG (d 1 to 40): -33 g/d for daily FENO duration. Our results demonstrated that FENO occurred frequently in bulls during the first weeks after entrance into a fattening operation and can last up to 11 d. The impact of FENO observed on ADG in this study indicated a potential benefit of treating affected animals, specifically those with FENO of long duration. However, further research is needed to determine the medical and economic relevance of such treatment.
Collapse
Affiliation(s)
- E Timsit
- LUNAM Université, ONIRIS, UMR 1300, Bio-aggression, Epidemiology and Risk Analysis, and INRA, Nantes, France.
| | | | | | | | | |
Collapse
|
49
|
Timsit E, Albaric O, Colle MA, Costiou P, Cesbron N, Bareille N, Assié S. Clinical and histopathologic characterization of a central and peripheral axonopathy in Rouge-des-prés (Maine Anjou) calves. J Vet Intern Med 2011; 25:386-92. [PMID: 21281347 DOI: 10.1111/j.1939-1676.2010.0662.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Recently, a progressive pelvic limb ataxia and paraparesis leading invariably to recumbency has been reported in Rouge-des-prés calves. OBJECTIVES To characterize the clinical and pathological findings of this newly reported disease and to investigate its potential causes. ANIMALS Nine calves from 7 different farms were prospectively studied from initial diagnosis through postmortem examination. METHODS Physical and neurological examinations, blood tests, cerebrospinal fluid (CSF) analysis, and myelographic examinations were performed. Neuropathology was carried out on both central and peripheral nervous systems. Copper deficiency and organophosphate intoxication also were investigated. Pedigrees were analyzed. RESULTS Age of onset varied from 2 to 6 weeks. Initial signs included pelvic limb ataxia and paraparesis. The neurological signs systematically progressed, over a 1-3-month period, to severe pelvic limb and truncal ataxia along with moderate paraparesis, leading to permanent recumbency. Animals remained alert. Cranial nerve function was normal. Muscle atrophy was not observed and spinal reflexes were normal. Blood tests, CSF analysis, and myelographic examination did not identify any abnormality. Neuropathology indicated neuronal fiber degeneration particularly in the dorsolateral and ventromedial funiculi of the spinal cord and in the peripheral nerves. Degenerative lesions also were observed in lateral vestibular and thoracic nuclei. No environmental factors such as copper deficiency or organophosphate intoxication could be incriminated as the cause of this axonopathy. Pedigree analysis suggested an inherited defect. CONCLUSIONS AND CLINICAL IMPORTANCE The first description of a central and peripheral axonopathy is reported in Rouge-des-prés calves. An inherited defect is highly suspected.
Collapse
Affiliation(s)
- E Timsit
- Department of Farm Animal Health and Public Health, ONIRIS, Nantes, France.
| | | | | | | | | | | | | |
Collapse
|
50
|
Timsit E, Assié S, Quiniou R, Seegers H, Bareille N. Early detection of bovine respiratory disease in young bulls using reticulo-rumen temperature boluses. Vet J 2010; 190:136-42. [PMID: 20947394 DOI: 10.1016/j.tvjl.2010.09.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 09/10/2010] [Accepted: 09/14/2010] [Indexed: 11/19/2022]
Abstract
The use of reticulo-rumen temperature boluses to detect bovine respiratory disease (BRD) was investigated in young bulls following their entry into a fattening unit. Twenty-four bulls received a bolus at entry and were observed for 40 days. As soon as a reticulo-rumen hyperthermia (RH) episode was detected using the bolus, clinical examination was performed by a veterinarian and then repeated every 12-24h until the end of RH episode. Fifty-two RH episodes were detected in 22 animals. High rectal temperatures (40.1±0.6°C) were observed during these episodes. BRD was diagnosed on the basis of clinical examination during 38/52 RH episodes in 21 animals (positive predictive value 73%). The onset of BRD signs always occurred after the onset of RH episodes, with a time-lag from 12 to 136 h, depending on BRD signs. Monitoring reticulo-rumen temperature permits early detection of BRD; however, clinical examination is required to confirm BRD.
Collapse
Affiliation(s)
- Edouard Timsit
- Ecole Nationale Vétérinaire, Agroalimentaire et de l'Alimentation, Nantes, France.
| | | | | | | | | |
Collapse
|