Gastrointestinal parasitosis in cattle: Unveiling the landscape across diverse production systems in Bangladesh

BACKGROUND

Factors influencing parasitosis in cattle in Bangladesh remain inadequately explored, necessitating a comprehensive investigation for interventions and sustainable livestock farming.

OBJECTIVES

We conducted this study to estimate the prevalence and distribution of gastrointestinal parasites, exploring their intricate relationship with farm management practices across a spectrum of small-, medium-, and large-scale commercial farms.

METHODS

We conducted this study in the Chattogram district of Bangladesh. We collected a total of 189 freshly voided faecal samples from different farms. We recorded the age, breed, milking status, sex, body condition score, and anthelmintic use history of the sampled animals. We processed the samples using the direct smear method, with the identification of one egg per sample being considered positive.

RESULTS

We estimated the prevalence of gastrointestinal parasite infection in large-scale (52.1%), medium-scale (54.5%), and small-scale farms (70.0%), with statistically significant differences (p ≤ 0.05). Both pregnant and lactating cows, as well as indigenous cattle, were more likely to have gastrointestinal parasites (p ≤ 0.05). The predominant parasites across farms of all sizes were trematodes (Paramphistomum spp. and Schistosomas spp.) and protozoa (Balantidium coli and Coccidia spp.).

CONCLUSION

Poor farm management practices, such as no pasture management and inadequate deworming regimens, may contribute to the elevated prevalence and infection load observed on small-scale farms. The increased parasitosis in previously dewormed animals can be attributed to the development of anthelmintic resistance against gastrointestinal parasites. Implementing proper and effective deworming strategies is crucial to preventing gastrointestinal parasitosis and mitigating the risk of anthelmintic resistance.

Antibiotic governance and use on commercial and smallholder farms in eastern China

Introduction

China is one of the largest consumers of agricultural antibiotics in the world. While the Chinese government has been tightening its regulations to control antimicrobial resistance (AMR) from animal sources in recent years, the extent of antimicrobial oversight and the practices of antibiotic use in animal agriculture in China has not yet been explored. This study describes the practices of antimicrobial management in eastern China and current scenarios of antibiotic use in commercial farms and smallholder backyard farming.

Methods

33 semi-structured interviews were conducted with government agriculture officials, veterinary drug sellers, farmers and smallholders in two contrasting areas of rural Zhejiang and Jiangsu provinces, China. Interview transcripts were analyzed in NVivo12 using a thematic approach.

Results

Findings revealed that although the governance of antibiotic use has made progress, especially in controlling irrational antibiotic use in commercial farms, smallholders are under-regulated due to a lack of resources and assumptions about their marginal role as food safety governance targets. We also found that smallholders resort to human antibiotics for the treatment of backyard animals because of economic constraints and lack of access to professional veterinary services.

Discussion

More attention needs to be devoted to the local structural needs of farmers to reduce antibiotic misuse. Considering the extensive links of AMR exposure under the One Health framework, efforts to integrate smallholders in antibiotic governance are required to address the AMR burden systematically in China.

Evolution and Introductions of Influenza A Virus H1N1 in a Farrow-to-Finish Farm in Guatemala

Commercial swine farms provide unique systems for interspecies transmission of influenza A viruses (FLUAVs) at the animal-human interface. Bidirectional transmission of FLUAVs between pigs and humans plays a significant role in the generation of novel strains that become established in the new host population. Active FLUAV surveillance was conducted for 2 years on a commercial pig farm in Southern Guatemala with no history of FLUAV vaccination. Nasal swabs (n = 2,094) from fattening pigs (6 to 24 weeks old) with respiratory signs were collected weekly from May 2016 to February 2018. Swabs were screened for FLUAV by real-time reverse transcriptase PCR (RRT-PCR), and full virus genomes of FLUAV-positive swabs were sequenced by next-generation sequencing (NGS). FLUAV prevalence was 12.0% (95% confidence interval [CI], 10.6% to 13.4%) with two distinct periods of high infection. All samples were identified as FLUAVs of the H1N1 subtype within the H1 swine clade 1A.3.3.2 and whose ancestors are the human origin 2009 H1N1 influenza pandemic virus (H1N1 pdm09). Compared to the prototypic reference segment sequence, 10 amino acid signatures were observed on relevant antigenic sites on the hemagglutinin. The Guatemalan swine-origin FLUAVs show independent evolution from other H1N1 pdm09 FLUAVs circulating in Central America. The zoonotic risk of these viruses remains unknown but strongly calls for continued FLUAV surveillance in pigs in Guatemala. IMPORTANCE Despite increased surveillance efforts, the epidemiology of FLUAVs circulating in swine in Latin America remains understudied. For instance, the 2009 H1N1 influenza pandemic strain (H1N1 pdm09) emerged in Mexico, but its circulation remained undetected in pigs. In Central America, Guatemala is the country with the largest swine industry. We found a unique group of H1N1 pdm09 sequences that suggests independent evolution from similar viruses circulating in Central America. These viruses may represent the establishment of a novel genetic lineage with the potential to reassort with other cocirculating viruses and whose zoonotic risk remains to be determined.

Quantitative relationship between the number of cross-fostering piglets and subsequent productivity of sows on commercial swine farms

The present study aimed to investigate the quantitative relationship between the number of cross-fostering (CF) piglets and subsequent productivity of sows. Data were obtained from seven commercial farms including 41,086 farrowing records. Sows were divided into those that fostered out three or more piglets (CF ≥ 3-), fostered out one or two piglets (CF1-2-), did not do CF (NCF), fostered in one or two piglets (CF1-2+), and fostered in three or more piglets (CF ≥ 3+). CF ≥ 3- sows had the lowest number of piglets weaned and the highest preweaning mortality rate, whereas CF ≥ 3+ sows had the second-lowest number of piglets weaned and the second-highest preweaning mortality rate (p < .05). The number of piglets weaned and preweaning mortality rate did not differ among CF1-2-, NCF, and CF1-2+ sows. CF ≥ 3+ sows had the lowest farrowing rate (p < .05). The number of piglets born alive at the subsequent parity was highest for CF ≥ 3- sows (p < .05), followed in order by CF1-2-, NCF, CF1-2+, and CF ≥ 3+ sows (p < .05). In summary, CF1-2- and CF1-2+ sows showed no decreases in productivity compared with NCF sows, whereas CF ≥ 3- and CF ≥ 3+ sows had reduced productivity.

Assessment of reproductive and growth performance of pigs on commercial swine farms in southern Kyushu, Japan

The objective of the present study was to assess the productivity of pigs to investigate the time-dependent change in productivity and compare productivity according to breeding company group and porcine reproductive and respiratory syndrome (PRRS) status on commercial swine farms in southern Kyushu, Japan. Data used in the present study were 245 annual productivity records from 2014 to 2018 obtained from 72 farms. Average sow inventory was 481.2 sows. Mean numbers of pigs weaned per sow per year and market pigs sold per sow per year were 23.7 and 21.6, respectively. Pigs born alive per litter increased from 11.1 to 11.9 pigs from 2014 to 2018 (p < .05). Farms using domestic breeding companies had similar numbers in 2016 to those using international breeding companies, but fewer pigs in 2014, 2015, 2017, and 2018 (p < .05). Farms with an unknown or unstable PRRS status had fewer pigs born alive per litter and pigs weaned per sow per year than those with stable or negative PRRS statuses (11.2 ± 0.06 vs. 11.8 ± 0.08 pigs and 22.6 ± 0.38 vs. 25.0 ± 0.22 pigs, respectively; p < .05). These results can be used to establish feasible targets and standards of performance to identify problem areas and improve production.

Piglet production by non-surgical transfer of vitrified embryos, transported to commercial swine farms and warmed on site

We investigated the feasibility of piglet production by non‐surgical embryo transfer (Ns‐ET) of vitrified porcine blastocysts and expanded blastocysts transported to commercial farms and warmed on site (V/T/W embryos). Ns‐ET was performed by depositing 11–20 vitrified and warmed embryos at a proximal site within the uterus via a catheter. In Experiment 1, the effect of donor–recipient estrous cycle asynchrony on the efficiency of Ns‐ET of vitrified and ordinary warmed embryos was investigated at the experimental facility. With a 1‐day delay recipients relative to that of donor, the farrowing rate was 50.0% and the survival rate to term was 21.1%. In Experiment 2, Ns‐ET using recipients with a 1‐day delay and vitrified embryos after one‐step warming and dilution was evaluated at the experimental facility. Although the resulting farrowing rate was 42.9%, the survival rate was 6.4%. In Experiment 3, Ns‐ET was conducted using V/T/W embryos at four commercial farms, where piglets derived from them were produced. When artificial insemination was conducted prior to Ns‐ET, the farrowing and survival rates obtained using V/T/W embryos were 75.0%, and 21.3%, respectively. These results show that Ns‐ET of V/T/W embryos using this protocol would be feasible for piglet production at farms.

Imperfection of Commercial Inactivated Salmonella Vaccine Against Salmonella Infantis During Induced Molting in Chickens and Proposed Evaluation Method

In the present study, we evaluated the continuance and efficacy of inactivated vaccine against Salmonella Infantis (SI) in chickens raised on a commercial farm. Chickens (88-days-old) were inoculated with 1 or 0.5 doses of commercially available trivalent inactivated Salmonella vaccine; anti-SI antibody titer was examined continuously for 11 mo thereafter. Molting was induced 11 mo after vaccination, and SI was administered orally. SI colony-forming units (CFUs) were measured in cecal feces, cecal contents, liver, and spleen samples. Anti-SI antibodies in the 1 dose vaccination group could be detected in at least 90% of cases until the end of testing. SI discharge was significantly reduced in birds treated with either dose of vaccine. However, SI CFUs were elevated in the induced molting group, regardless of vaccination dose, particularly in the cecal feces, cecal contents, and spleen. Thus, the vaccine provided remarkable protection against SI infection under ordinary rearing methods but not during induced molting. To achieve sufficient SI protective efficacy, we recommend inoculation with 1 dose of vaccine. Moreover, the efficacy of inactivated Salmonella vaccine is recommended to be evaluated by challenging chickens with live Salmonella in addition to Salmonella antibody titration.

Highly Pathogenic Avian Influenza A(H7N9) Virus, Tennessee, USA, March 2017

In March 2017, highly pathogenic avian influenza A(H7N9) was detected at 2 poultry farms in Tennessee, USA. Surveillance data and genetic analyses indicated multiple introductions of low pathogenicity avian influenza virus before mutation to high pathogenicity and interfarm transmission. Poultry surveillance should continue because low pathogenicity viruses circulate and spill over into commercial poultry.