Comparison of bovine hematology reference intervals from 1957 to 2006

Hematologic and Serum Biochemical Characteristics of Belgian Blue Cattle

Belgian blue (BB) cattle have an 11-bp deletion in myostatin that causes skeletal muscle hyperplasia and increased muscle mass, leading to a 'double-muscled' phenotype. Preliminary data suggest that this phenotype may be associated with breed-specific hematologic and biochemical values. Therefore, in this study, we sought to compare hematologic and serum biochemical parameters in healthy BB and Holstein Friesian (HF) cows and to propose breed-specific reference intervals for BB cows. Hematologic parameters, total protein, creatinine, creatine kinase (CK) and aspartate transaminase (AST) activities, albumin, and globulins were measured in 183 clinically healthy adult BB and HF cows. There were significant differences between BB and HF cows in 17 of 27 measured parameters. BB cows had significantly higher creatinine concentration and CK and AST activities (p < 0.001). RBCs, hemoglobin, hematocrit (p < 0.001), MCV and lymphocytes (p < 0.05) were also significantly higher in BB cows compared with HF cows. The average N/L ratio was greater than 1 in both breeds. These results suggest that BB and HF cows have significantly different clinically relevant hematologic and serum biochemical values, and, therefore, breed-specific reference intervals should be used.

Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle

Subfertility remains a major problem in the dairy industry. Only 35-40% of high-yielding dairy cows and 55-65% of nonlactating heifers become pregnant after their first service. The immune system plays a critical role in the establishment of pregnancy. However, it can also create challenges for embryo survival and contribute to reduced fertility. We conducted 2 separate experiments to characterize changes in subsets of peripheral blood leukocytes (PBL) and their phenotype over the estrous cycle and early pregnancy in heifers and cows. We used flow cytometry and RT-qPCR to assess protein and mRNA expression of molecules important for immune function. We observed that monocytes and T cells were most affected by pregnancy status in heifers, whereas, CD8+ lymphocytes and natural killer (NK) cells were most affected during early pregnancy in cows. Changes in immune parameters measured appeared to be greater in heifers than cows including changes in expression of numerous immune function molecules. To test the hypothesis, we conducted a third experiment to simultaneously analyze the immunological responses to pregnancy between cows and heifers. We observed that cows had greater expression of proinflammatory cytokines and molecules associated with leukocyte migration and phagocytosis compared to heifers. Moreover, animals that failed to become pregnant showed altered expression of anti-inflammatory molecules. Overall, these findings support the hypothesis that early pregnancy signaling alters the proportions and functions of peripheral blood immune cells and differences between cows and heifers may yield insight into the reduced fertility of mature lactating dairy cows.

Observational longitudinal study on Toxoplasma gondii infection in fattening beef cattle: serology and associated haematological findings

Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is a globally distributed zoonotic infection with significant implications for human and animal health. This study investigated the prevalence of T. gondii infection in a population of beef cattle at three different stages of their productive lifespan and examined the impact of T. gondii serological status on blood parameters. A commercial beef fattening unit in Italy was the setting for this research, which involved a biosecurity assessment upon cattle arrival, blood sampling at three time points and Toxoplasma-specific serological testing using indirect fluorescent antibody tests (IFAT). Results revealed a dynamic pattern of T. gondii seropositivity in cattle, with an initial prevalence of 30.6% at arrival (T0) that increased to 44.6% at 14 days (T1) and then decreased slightly to 39.3% at slaughter after 5 months (T2). Interestingly, seroconversion was observed during the study, indicating ongoing infections, and antibody waning occurred in some animals. In terms of blood parameters, seropositive cattle exhibited significantly lower mean corpuscular volume (MCV) and a higher neutrophil-lymphocyte (N/L) ratio, suggesting an activation of the innate immune response. Furthermore, cattle with higher antibody titres displayed higher neutrophil counts. However, all blood parameters with a statistical significance were within the reference range. This study provides for the first time a longitudinal investigation on the serological status for T. gondii in naturally exposed beef cattle. These findings provide valuable insights into the clinico-pathological aspects of natural T. gondii exposure in cattle and underscore the importance of monitoring and managing T. gondii infection in livestock production systems.

Genetic background of hematological parameters in Holstein cattle based on genome-wide association and RNA sequencing analyses

Hematological parameters refer to the assessment of changes in the number and distribution of blood cells, including leukocytes (LES), erythrocytes (ERS), and platelets (PLS), which are essential for the early diagnosis of hematological system disorders and other systemic diseases in livestock. In this context, the primary objectives of this study were to investigate the genomic background of 19 hematological parameters in Holstein cattle, focusing on LES, ERS, and PLS blood components. Genetic and phenotypic (co)variances of hematological parameters were calculated based on the Average Information Restricted Maximum Likelihood (AIREML) method and 1,610 genotyped individuals and 5,499 hematological parameter records from 4,543 cows. Furthermore, we assessed the genetic relationship between these hematological parameters and other economically important traits in dairy cattle breeding programs. We also carried out genome-wide association studies and candidate gene analyses. Blood samples from 21 primiparous cows were used to identify candidate genes further through RNA sequencing (RNA-seq) analyses. Hematological parameters generally exhibited low-to-moderate heritabilities ranging from 0.01 to 0.29, with genetic correlations between them ranging from -0.88 ± 0.09 (between mononuclear cell ratio and lymphocyte cell ratio) to 0.99 ± 0.01 (between white blood cell count and granulocyte cell count). Furthermore, low to moderate approximate genetic correlations between hematological parameters with one longevity, 4 fertility, and 5 health traits were observed. One-hundred-and-99 significant single nucleotide polymorphisms (SNP) located primarily on the Bos taurus autosomes (BTA) BTA4, BTA6, and BTA8 were associated with 16 hematological parameters. Based on the RNA-seq analyses, 6,687 genes were significantly downregulated and 4,119 genes were upregulated when comparing 2 groups of cows with high and low phenotypic values. By integrating genome-wide association studies (GWAS), RNA-seq, and previously published results, the main candidate genes associated with hematological parameters in Holstein cattle were ACRBP, ADAMTS3, CANT1, CCM2L, CNN3, CPLANE1, GPAT3, GRIP2, PLAGL2, RTL6, SOX4, WDFY3, and ZNF614. Hematological parameters are heritable and moderately to highly genetically correlated among themselves. The large number of candidate genes identified based on GWAS and RNA-seq indicate the polygenic nature and complex genetic determinism of hematological parameters in Holstein cattle.

Hematological Normality, Serum Biochemistry, and Acute Phase Proteins in Healthy Beef Calves in the Brazilian Savannah

The Brazilian savannah region, characterized by high average temperatures, well-defined rainy and dry seasons, soil with low productive potential, and high pressure for parasitic diseases, is home to the highest percentage of the beef herd, which is the world's largest commercial beef producer. Therefore, breeds that present rusticity combined with productivity are the focus of research in cattle breeding in the region. Considering their geographic particularities and their effects on the animals' blood parameters, the objective was to study the behavior of hematological variables, serum biochemistry, and acute phase proteins in beef calves at weaning age. Jugular blood samples were collected in a single day from 30 weaning calves (about eight months old and 200 kg of body weight) from the following breeds: Nellore, Senepol, Nellore × Aberdeen Angus cross, Nellore × Senepol cross, and Nellore × Aberdeen Angus × Senepol cross. Hematological data were obtained using an automatic cell counter, serum biochemical measurements were obtained using commercial kits, and the electrophoretogram was obtained using the SDS-page technique. In general, the results were consistent with data already published in similar situations regarding health status, age, and level of metabolic activity. However, differences observed between groups can be explained by differences observed in other concurrent variables like temperament. The pure zebu breed was more reactive than pure taurine. While crossbreds showed intermediate values, and parasitic infestation, the pure taurine breed with higher parasite infestation, while the zebu breed had lower values, which produced effects in some laboratory tests, and generated differences between breeds. In conclusion, the reference intervals available for healthy animals can be routinely used without interference from the geographic region for animals produced without nutritional failures as long as changes are recorded in pathological, infectious, metabolic, or nutritional deficiency situations. However, it is suggested that a study covering a larger number of herds may demonstrate a greater geographic effect on the studied variables.

Haematological values in cattle reared in humid and subhumid tropics of Mexico

The objective of this study was to determine some factors that influence the haematological values of cattle reared in the humid and subhumid tropics of Mexico. Whole blood samples were taken from 1355 crossbred cattle in the years 2017 to 2019. Haematocrit (HTC, %), total plasma protein (TPP, g/dL) and peripheral eosinophils count (PEOS, × 10³/µL) were determined manually, and the main haematological variables were recorded with an automatic analyser. The statistical analysis considered as classification variables age, sex, season (cold, dry and rainy), year (2017, 2018 and 2019) and origin of the cattle. The mean of the haematological parameters was determined along with the confidence limits (CL) of the different categories of animals according to age. Calves younger than 1-year-old presented higher levels of HTC, red blood cell count (RBC), haemoglobin (HGB), red blood cell distribution width (RDW), platelet number (PLT), white blood cell count (WBC) and lymphocyte count (LYMF) than animals older than 2 years of age. However, they showed the lowest mean cell volume (MCV) and TPP values. In cows, the highest levels of PEOS, granulocytes (GRAN), MCV and medium cells (MID) were observed and the lowest HTC, RBC, RDW and WBC levels. Intervals were determined with the 1st quartile (Q1) or lower confidence interval (90% CI) as the minimum values and the 3rd quartile (Q3) or upper confidence interval (90% CI) as the maximum values. The haematological parameters of cattle reared in the Southeast of Mexico are significantly affected by age, sex and environmental conditions.

Health and welfare assessment of beef cattle during the adaptation period in a specialized commercial fattening unit

Beef cattle welfare and health status are influenced by housing and management systems. The present study aimed to assess the welfare and health status in the first 15 days after arrival of Limousine bulls imported from France and fattened in a commercial fattening unit in Italy. A total of 264 bulls were included in the study. Welfare, biosecurity, and major hazard and warning system were assessed on days 2 (T1) and 15 (T2) after arrival to the unit. At T1 and T2 an inspective clinical examination was performed on all bulls. At T1 and T2 blood samples were collected from 88 bulls for haematological analysis. Both at T1 and T2, the welfare, biosecurity, and major hazards and warning systems were classified with a general score of medium but with a decrease on animal-based measurements in T2. At T1 and T2 the clinical examination revealed a significant increase (p-value≤0.05) of skin lesions and lameness in T2. A high incidence of respiratory disease was noticed in both assessed times. Leucocytes and all differentials count, and platelets were significantly increased (p-value≤0.05) at T2, while the fibrinogen was significantly decreased. The haematological changes suggest that the bulls were under higher stress in T2 when compared with T1 linked with a difficult adaptation response to the fattening unit. A multi-factorial approach that integrates the indicators of the checklist and the clinical and haematological findings of animals can be a useful method to deepen the assessment of welfare in beef cattle.

The Effect of Indigo (Indigofera tinctoria L.) Waste on Growth Performance, Digestibility, Rumen Fermentation, Hematology and Immune Response in Growing Beef Cattle

This experiment was conducted to assess the effect of indigo waste on the feed intake, digestibility, rumen fermentation, hematology, immune response and growth performance in growing beef cattle. Twenty crossbred beef cattle with an initial body weight (BW) of 145 ± 11 kg were fed four levels of indigo waste for 90 days in a trial. Additions of indigo waste at 0%, 10%, 20% and 30% in a concentrate diet using a completely randomized design (CRD). Cattle were fed concentrate at 1.8% BW, with rice straw fed ad libitum. The concentrate intake decreased linearly (p = 0.01) with the addition of indigo waste. The supplementation with indigo waste reduced dry matter (DM) and organic matter (OM) digestibility cubically (p = 0.03 and p = 0.02, respectively), while increasing neutral detergent fiber (NDF) digestibility cubically (p = 0.02). The final BW of beef cattle decreased linearly (p = 0.03) with the addition of indigo waste. The inclusion of indigo waste decreased the average daily gain (ADG) and gain-to-feed ratio (G:F) linearly (p < 0.01) from 0 to 90 days. The nutrient digestibility, ADG and G:F of beef cattle fed 10% indigo waste in the diet was similar when compared with the control (0% indigo waste). The ruminal pH, ammonia-nitrogen (NH3-N) and total volatile fatty acid (VFA) concentrations were similar among treatments (p > 0.05). The proportion of acetate increased linearly (p < 0.01) but propionate decreased linearly (p < 0.01), resulting in an increase in the acetate to propionate ratio (p < 0.01) when cattle were fed with indigo waste supplementation. Increasing indigo waste levels did not influence blood urea nitrogen (BUN) levels, hematological parameters or immune responses (IgA, IgM and IgG) (p > 0.05). In conclusion, the inclusion of indigo waste at 10% in a concentrate diet did not have a negative effect on feed intake, nutrient digestibility, rumen fermentation, hematology, immune function or growth performance in growing beef cattle.

Molecular, Physiological and Hematological Responses of Crossbred Dairy Cattle in a Tropical Savanna Climate

A comprehensive study was conducted to assess the effects of seasonal transition and temperature humidity index (THI) on the adaptive responses in crossbred dairy cows reared in a tropical savanna region. A total of 40 lactating dairy cattle reared by small-scale dairy farmers in Bengaluru, India, were selected for this study. The research period comprised the transitioning season of summer to monsoon, wherein all traits were recorded at two points, one representing late summer (June) and the other early monsoon (July). A set of extensive variables representing physiological responses (pulse rate, respiration rate, rectal temperature, skin surface temperature), hematological responses (hematological profile), production (test day milk yield, milk composition) and molecular patterns (PBMC mRNA relative expression of selective stress response genes) were assessed. A significant effect of seasonal transition was identified on respiration rate (RR), skin surface temperature, mean platelet volume (MPV), platelet distribution width (PDWc), test day milk yield and on milk composition variables (milk density, lactose, solids-not-fat (SNF) and salts). The THI had a significant effect on RR, skin surface temperature, platelet count (PLT), plateletcrit (PCT) and PDWc. Lastly, THI and/or seasonal transition significantly affected the relative PBMC mRNA expression of heat shock protein 70 (HSP70), interferon beta (IFNβ), IFNγ, tumor necrosis factor alpha (TNFα), growth hormone (GH) and insulin-like growth factor-1 (IGF-1) genes. The results from this study reveal environmental sensitivity of novel physiological traits and gene expressions to climatic stressors, highlighting their potential as THI-independent heat stress biomarkers.

A Case Study of Photosensitivity Associated with Anaplasma spp. Infection in Cattle

Anaplasma infection has not previously been reported as a cause of photosensitization. This case presents a five-year-old Holstein cow in her fifth month of gestation with skin injury of nonpigmented areas clearly delimited from adjacent unaffected pigmented skin. Specific lesions included alopecia, localized oedema, desquamation erythema, serous exudation, thick detached skin, fissures, crusting, and necrosis, indicating photodermatitis. Hematological abnormalities were leukocytosis with neutrophilia and normocytic hypochromic anemia. Based on a hemoparasitic examination of blood smears, the organism Anaplasma spp. was observed within the red blood cells. Biochemical analyses revealed increased serum liver enzyme activity associated with hepatocellular damage and cholestasis. This cow was RT-PCR positive for Anaplasma spp. infection. After treatment with oxytetracycline started, its condition improved within 24 h, and it recovered completely within 30 days. In this case, the underlying pathogenic mechanism of Anaplasma spp. infection facilitated the impairment of bile flow and liver function, resulting in hepatogenous photosensitization.

Hematology Reference Intervals for Holstein Cows in Southern China: A Study of 786 Subjects

Hematology RIs help clinicians and researchers determine whether a hematology parameter is abnormal, which plays an important role in animal health surveillance. China is one of the largest dairy producers in the world, with millions of Holstein cows. However, there has been no published data on hematology RIs for dairy cows in China yet. Therefore, the aim of this study is to establish updated and accurate RIs for Holstein cows in southern China. To increase the accuracy of the RIs, we collected blood samples from 786 Holstein cows and analyzed 25 hematologic variables. The RIs for Holstein cows were established using the 95% percentile RIs according to the American Society of Veterinary Clinical Pathology guidelines. The effects of different ages, parities and lactation stages were also checked in this study. The data of 21, 22 and 19 out of 25 hematology parameters were significantly different between different ages, parities and lactation stages, respectively. Furthermore, the hematology RIs of separate subclasses according to different ages, parities and lactation stages were generated. Hematology RIs according to ages and lactation stages, as well as parities and lactation stages, were also assessed. Together, our results confirm that hematology RIs for cows vary by ages, parities and lactation stages. The present study helps to fill the gap in hematology RIs for Holstein cows in southern China, and our data may serve as a very useful tool for monitoring the health and welfare of dairy cattle in China.

Review of the Current Research on Fetal Bovine Serum and the Development of Cultured Meat

The purpose of this review is to summarize studies that investigate blood and the main components of fetal bovine serum (FBS) in vertebrates, including major livestock, and review the current research on commercializing cultured meat. Detailed research on FBS is still lacking; however, some studies have shown that FBS consists of proteins, carbohydrates, growth factors, cytokines, fats, vitamins, minerals, hormones, non-protein nitrogen, and inorganic compounds. However, there are few studies on how the composition of FBS differs from blood or serum composition in adult animals, which is probably one of the main reasons for not successfully replacing FBS. Moreover, recent studies on the development of FBS replacers and serum-free media have shown that it is difficult to conclude whether FBS has been completely replaced or serum-free media have been developed successfully. Our review of the industrialization of cultured meat reveals that many basic studies on the development of cultured meat have been conducted, but it is assumed that the study to reduce or replace ingredients derived from fetuses such as FBS has not yet been actively developed. Therefore, developing inexpensive and edible media is necessary for the successful industrialization of cultured meat.

Development of a predictive model for bovine leukemia virus proviral load

Background

There is currently no commercially available method in Canada to identify bovine leukemia virus (BLV)‐positive cows with high proviral load (PVL).

Objectives

First, develop a model to predict PVL using common, commercially available, cost‐effective diagnostic tests. Second, investigate the relationship between lymphocyte count and PVL in BLV‐positive cows.

Animals

A total of 339 BLV‐positive and 62 BLV‐seronegative cows on 15 dairy farms.

Methods

Cross‐sectional study. Blood and milk samples were collected from all lactating BLV‐positive cows on each farm and 5 to 10 BLV‐seronegative cows depending on herd size. Blood and milk samples were tested for anti‐BLV antibodies using enzyme‐linked immunosorbent assay (ELISA). Complete blood counts were performed on blood samples, and standard components analyses were obtained for milk samples. Proviral load was determined by quantitative polymerase chain reaction for each cow.

Results

The inverse of lymphocyte count, the square of the inverse of lymphocyte count, and milk ELISA percent positivity were positively associated with increasing PVL in BLV‐positive cows. For BLV‐positive cows, lymphocyte count >5.2 × 10⁹/L predicted a high PVL (BLV:Bovine DNA of >1 in blood) with a sensitivity of 92.4% and a specificity of 79.8%. For BLV‐positive cows, white blood cell count >10.8 × 10⁹/L predicted a high PVL, with a sensitivity of 85.5% and a specificity of 83.6%.

Conclusions and Clinical Importance

Based on these results, producers can implement commonly available diagnostic tests to identify cows with high probability of having high PVL, which may help in designing effective disease control strategies for BLV‐positive herds.

Adrenergic receptor gene expression in bovine leukocytes

The α- and β-adrenergic receptors (ARs) bind the stress hormones epinephrine (E), norepinephrine (NE), and dopamine and activate diverse physiological responses. A lack of information on AR gene expression in leukocytes limits our understanding of how stress alters immune function. Quantitative analyses of AR gene expression was completed for bovine leukocytes. Individual leukocyte lineages and subpopulations within lineages were isolated with high-speed cell sorting to facilitate a targeted analysis of AR gene expression. These analyses confirmed all 9 AR genes were expressed in bovine leukocytes with marked differences in AR gene expression when comparing among leukocyte lineages. Furthermore, separation of polymorphonuclear cells into neutrophils and eosinophils revealed these key innate immune cells also differ significantly in AR gene expression. This study provides the first comprehensive survey of AR gene expression in immune cells of any mammalian species and provides insight into conflicting reports that stress can either activate or suppress immune function.

Hematological and immunological responses to naturally occurring bovine respiratory disease in newly received beef calves in a commercial stocker farm

The objective was to determine temporal changes in hematological and immune parameters in response to naturally occurring bovine respiratory disease (BRD) in commercially managed stocker calves. Forty newly weaned beef steers purchased from auction markets were housed at a commercial stocker operation in Crossville, TN. Blood samples, rectal temperature, and thoracic ultrasonography (TUS; 1: normal to 3: severe) were collected on days 0, 7, 14, and 21. Castration status (FC: freshly castrated; PC: previously castrated) was determined on arrival based on presence of a fresh castration site at the scrotum. Calves received antibiotics for BRD based on clinical severity scoring (CSS; 0: moribund, 4: moribund) and rectal temperature. Complete blood counts (CBC) were performed. Calves were categorized based on the number of treatments (NumTrt) received (0x, 1x, and 2x). Temporal variations in CBC and immune parameters were analyzed using mixed model repeated measure ANOVA (Proc GLIMMIX; SAS 9.4). Variation of CBCs and immune parameters based on TUS was determined using mixed model ANOVA. There was a NumTrt by day interaction effect on the responses of white blood cells (WBC) (P = 0.04) and haptoglobin (HPT) (P = 0.04). On day 21, WBC were greater in the 2x NumTrt group than other groups, but there were no differences in WBC between NumTrt levels on other days. Haptoglobin was greater in the 2x group on days 14 and 21 than 0x or 1x. Red blood cells (RBC) (P = 0.02) and WBC (P = 0.04) differed between FC and PC groups, and lower RBC and WBC were observed in the FC group. A castration status × day effect for mean corpuscular volume (MCV; P = 0.04) was observed where FC group had higher MCV at days 14 and 21 than the PC group. Tumor necrosis factor-α differed based on NumTrt (P = 0.03) and higher concentrations were found in 2x group. We observed a day effect for IL-1β (P = 0.009) and TNF-α (P = 0.001). Significant effect of TUS on HPT at day 14 (P = 0.0004) and day 21 (P = 0.002) was observed. Combining HPT and platelet explained 15% of the variability in treatment status on a given day, whereas HPT and hemoglobin explained 10% of the variability in lung consolidation status. Although hematological and immunological parameters varied largely in our study, the potential of combining HPT with hematological variables should be studied further. Results from this study would help in understanding temporal changes in CBC and immune parameters in newly received stocker cattle.

Diagnostic Measures of Disease Progression in Cattle Following Natural Infection with Bovine Leukemia Virus

This study describes the longitudinal changes in bovine leukemia virus (BLV) ELISA antibodies, proviral load (PVL), and blood lymphocyte counts (LC) observed over a 2.5-year period in naturally infected cattle. The dataset utilized was from a BLV intervention field trial on three Midwestern dairy herds. Our analysis showed ELISA false negatives were more likely to occur in cattle with low PVL and normal LC. On average, negligible changes in LC were observed during six-month intervals. Periods of lymphocytosis, defined as >10,000 lymphocytes per uL of blood, were observed in 31.5% (68/216) of BLV test-positive cattle. In BLV test-positive cows, an average increase of 2900 to 3100 proviral copies per 100,000 cells was observed during each subsequent six-month sampling interval. The difference between the minimum and maximum PVL observed for an ELISA-positive cow with 3 or more observations ranged from 0 to 115,600 copies per 100,000 cells (median: 12,900; mean: 19,200). Therefore, following the identification of ELISA-positive cattle and the assessment of PVL and LC, subsequent semiannual tests to assess disease progression may not be needed. Further work is needed to determine how available diagnostic tests can be optimized to design cost-effective testing schemes for BLV control programs.

A Review of the Neutrophil Extracellular Traps (NETs) from Cow, Sheep and Goat Models

This review provides insight into the importance of understanding NETosis in cows, sheep, and goats in light of the importance to their health, welfare and use as animal models. Neutrophils are essential to innate immunity, pathogen infection, and inflammatory diseases. The relevance of NETosis as a conserved innate immune response mechanism and the translational implications for public health are presented. Increased understanding of NETosis in ruminants will contribute to the prediction of pathologies and design of strategic interventions targeting NETs. This will help to control pathogens such as coronaviruses and inflammatory diseases such as mastitis that impact all mammals, including humans. Definition of unique attributes of NETosis in ruminants, in comparison to what has been observed in humans, has significant translational implications for one health and global food security, and thus warrants further study.

Hematological Changes and Reference Intervals in Hanwoo Calves during the First 28 Weeks of Life

Simple Summary

Complete blood cell count is important in identifying diseases in animals, and reference intervals must be established considering physiologic differences in genotype, age, sex, and management. However, little research has been performed to evaluate complete blood cell count reference intervals in Hanwoo calves. Therefore, we compared the complete blood cell count reference intervals of Hanwoo cows and Hanwoo calves and examined changes in calves’ complete blood cell count from birth to 28 weeks. We confirmed that complete blood cell count reference intervals specifically for calves are necessary for accurate diagnosis of calf diseases. In addition, the difference in complete blood cell count between female calves and male calves was confirmed for only some ages and some parameters. Our results suggest that reference intervals for Hanwoo calf complete blood cell count are necessary for accurate diagnosis of calf diseases

Abstract

Hematological reference intervals must consider several parameters, including genotype, age, sex, management, and analytic process. Work is needed to evaluate hematological changes specifically in Hanwoo calves and according to calf sex. Therefore, in this study, we sought to confirm the complete blood cell count (CBC) reference intervals in Hanwoo calves, to monitor changes in hematologic values in Hanwoo calves from birth until 28 weeks of life, and to compare the hematologic values of male and female calves. A total of 35 male calves and 35 female calves was studied. Calf blood was sampled at multiple intervals from the time of birth until 28 weeks of age (including within 6 h of birth and at 2 days, 7 days, and 4 weeks and then at 4-week intervals through 28 weeks). In addition, blood samples were collected from 210 clinically healthy pregnant Hanwoo cows to establish CBC reference intervals for adult cattle. There were significant differences in the results of the cows and calves in all 14 parameters considered. The CBC reference intervals of the calves were wider than those of the cows in all parameters except mean corpuscular volume, mean corpuscular hemoglobin concentration, and mean platelet volume. We also identified differences from birth through 28 weeks between male and female calves at only some ages and some parameters. These results suggest that CBC reference intervals specific to Hanwoo calves are necessary for accurate diagnosis of calf diseases.

Hematology and biochemistry of buffalo (Bubalus bubalis): influence of sex and age on reference values

This research aimed to obtain a hematological and biochemical profile of buffalos (Bubalus bubalis) bred in a region of the Brazilian Legal Amazon. A total of 73 animals of mixed races, divided into three groups, were studied: group 1 (G1) comprised animals up to 11 months old; in group 2 (G2), subjects were 12 to 23 months old; and, in group 3 (G3), they were 24 months old and older. We performed the hematological analysis manually, and, for the biochemistry, we used biochemical analyzers. Age of the animals has influenced the monocyte count. The counting of these cells was higher (p > 0.05) in younger animals (G1). There was no difference (p > 0.05) in hematological parameters concerning sex. In regard to biochemistry, we found that age influenced results for albumin and urea. Animals from G1 had higher albumin values when compared to G2 and G3. Serum urea values were higher in animals from G3. Regarding the serum mineral parameters, there were no significant results when the different age groups and both sexes were compared. Thus, the hematological and biochemical values obtained can work as a reference for the bubaline species of animals bred in the studied region, under the same management and breeding conditions. Sex and age of the animals are necessary for the interpretation of the tests.

Observational Study on Variation of Longitudinal Platelet Counts in Calves over the First 14 Days of Life and Reference Intervals from Cross-Sectional Platelet and Leukocyte Counts in Dairy Calves up to Two Months of Age

Simple Summary

To define a healthy animal in an experimental setting or to differentiate and backup a diagnosis in cattle practice, reference intervals (RIs) in haematology diagnostics are necessary. The RIs in calves for blood cell counts, such as platelets and white blood cells, differ from RIs in adult cattle and are not widely studied. Blood results from dairy calves in the Netherlands were used to study the variation in platelet counts in young calves and to calculate an RI for platelet and white blood cell counts. In new-born calves up to six days of age, platelet counts were lower than in calves older than five days. From six days of age until 60 days of age we propose an RI platelet count of 287–1372 × 10⁹/L and for the first 60 days of life an RI for leukocyte count of 4.0–18.9 × 10⁹/L.

Abstract

Platelet and leukocyte count reference intervals (RIs) for cattle differ by age and while adult RIs are known, RIs for calves are studied less. The aims of this observational study are to evaluate variation of platelet counts of Holstein Friesian calves over the first 14 days of life and to propose RIs for platelet and leukocyte counts of Holstein Friesian calves aged 0–60 days. In a longitudinal study, 19 calves were blood sampled 17 times, in the first 14 days of their lives. Blood was collected in a citrate blood tube and platelet counts were determined. We assessed the course of platelet counts. In a field study, 457 healthy calves were blood sampled once. Blood was collected in an EDTA blood tube and platelet and leukocyte counts were determined. The RIs were calculated by the 2.5 and 97.5 percentiles. Platelet counts started to increase 24 h after birth (mean platelet count 381 × 10⁹/L ± 138 × 10⁹/L) and stabilized after five days (mean platelet count 642 × 10⁹/L ± 265 × 10⁹/L). In calves up to six days of age, platelet counts were lower than in calves older than five days. In conclusion, the RIs of platelet and leukocyte counts in calves were wider in range than the RIs for adult cattle, therefore, calf specific RIs for platelet and leukocyte counts should be used. From 6 until 60 days of age, we propose an RI for platelet counts of 287–1372 × 10⁹/L and for the first 60 days of life an RI for leukocyte counts of 4.0–18.9 × 10⁹/L.

Effects of dietary electrolytes, osmolytes, and energetic compounds on body temperature indices in heat-stressed lactating cows

Objectives were to determine the effects of a product containing electrolytes, osmolytes, and energetic compounds (EOEC) on body temperature indices in heat-stressed (HS) Holstein cows. Lactating cows were assigned to 1 of 2 treatments: 1) a control diet (n = 10) or 2) a control diet supplemented with 113 g/d of EOEC (n = 10; Bovine BlueLite® Pellets; TechMix LLC, Stewart, MN). The trial consisted of 2 experimental periods (P). During P1 (4 d), cows were fed their respective treatments and housed in thermoneutral conditions. During P2 (4 d), HS was artificially induced using an electric heat blanket (EHB). Overall, HS markedly increased vaginal temperature (Tv), rectal temperature (Tr), skin temperature (Ts), and respiration rate (RR) (P < .01). There were no dietary treatment differences in Tv, Tr, or RR; however, during P2 EOEC-supplemented cows had increased Ts (0.8 °C; P = .04). Compared to P1, HS decreased DMI and milk yield (45 and 27%, respectively, P < .01) similarly amongst treatments. Relative to P1, circulating insulin decreased (41%; P = .04) in CON cows, whereas it remained unaffected in EOEC-supplemented cows, resulting in a 2-fold increase in EOEC compared with CON-fed cows (P < .01) during P2. Relative to P1, HS increased circulating non-esterified fatty acids (NEFA; 63%; P < .01). During P2, there tended to be a treatment by day interaction on circulating NEFA, as concentrations decreased from d 2 to 4 of P2 in EOEC-fed cows but continued to increase in CON cows. In summary, feeding EOEC altered some key aspects of energetic metabolism and increased Ts.

Effects of 5-aminolevulinic acid supplementation on milk production, iron status, and immune response of dairy cows

The objective of this study was to investigate the effect of 5-aminolevulinic acid (5-ALA) as a dietary supplement on milk yield and composition as well as iron status and immune response in lactating dairy cows. In this study 13 lactating Holstein cows were randomly assigned to either a control group or a treatment group supplemented with 10 mg of 5-ALA per kilogram of dry matter. During feeding, 5-ALA was mixed with a small amount of the total mixed ration and top-dressed. The experiments followed a crossover design with 2 periods. Each period consisted of an adaptation period of 12 d and a test period of 2 d. Dairy cows fed the diet supplemented with 5-ALA exhibited increased counts of white blood cells and granulocytes compared with the control group. The rate of phagocytosis and mitogen-induced proliferation of peripheral blood mononuclear cells in cows fed 5-ALA were higher than in cows fed a basal diet. However, 5-ALA did not affect iron status or plasma biochemical composition. Supplementation with 5-ALA improved milk protein and milk casein contents; however, it had no effect on milk production, milk fat, lactose, total solids, or solids-not-fat, compared with the control. We conclude that dietary supplementation of 5-ALA to lactating dairy cows may have a positive effect on milk protein synthesis and the immune response.

Disseminated thymic B-cell lymphoma in a Holstein heifer

A 19-mo-old Holstein heifer was inactive and dyspneic. Physical examination revealed wheezing, exophthalmos, a cervical mass, and lymphadenopathy. Cytology of the cervical mass and lymph nodes showed predominantly large atypical lymphocytes. Lactate dehydrogenase and thymidine kinase activities were elevated. Although nested PCR for bovine leukemia virus (BLV) using blood was positive, quantitative PCR showed a low number of provirus copies. Autopsy revealed enlargement of most lymph nodes examined, as well as white masses of various sizes in muscles of the left hindlimb and thoracic and abdominal organs. Histopathology revealed severe infiltration with neoplastic lymphocytes in these organs. The cervical mass was immune-positive for B-cell markers. The final diagnosis was thymic B-cell lymphoma with BLV infection.

Bovine leukemia virus pre-miRNA genes' polymorphism

MicroRNAs (miRNAs) are small non-coding RNAs with a wide distribution in nature among the living things. They play a key role both in normal signaling pathways and in pathological ones. Bovine leukemia virus (BLV) is an oncogenic retrovirus of Deltaretrovirus genus causing persistent infection in its natural hosts - cattle, zebu and water buffalo with diverse clinical manifestations through the defeat of B-lymphocytes (B-cells). Ten BLV encoded miRNAs (further miRs-B) transcribed from five different pre-miRNA (further pre-miR-B) genes are abundantly detected in BLV infected B-cells. Here we report about several alleles of each of pre-miRs-B' genes, some of which have a highly significant association with an increase or a decrease of the number of leukocytes (WBCs - white blood cells) in BLV-infected cows.

The effectiveness of colostral antibodies for preventing bovine leukemia virus (BLV) infection in vitro

BACKGROUND

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis (EBL). The incidence of EBL in Japan is increasing annually; and the cases of EBL in cattle younger than 2 years old has been reported. Therefore, it is vital to find a method to control BLV infection, especially in young calves. In this study, to evaluate the protective ability of colostral antibodies against BLV infection, as well as the potential for BLV infection mediated by colostrum/milk, we investigated temporal fluctuations in the anti-BLV antibody titer and BLV proviral load (PVL) in colostrum/milk and peripheral blood of six infected dams during lactation. The association between PVL and antibody titer in colostrum and peripheral blood was then investigated using samples from a further twenty-seven cattle. Antibody concentrations were measured with a Syncytium-induction Inhibition Assay using colostral/milk whey and serum. PVL in peripheral blood and colostrum was measured by real-time PCR.

RESULTS

Colostral antibodies showed high inhibitory activity until day 3 of lactation. The antibody titer and PVL in peripheral blood showed lesser changes than those in colostrum/milk throughout lactation. The colostral antibody titer was significantly higher than the serum antibody titer in all samples, whereas the colostrum PVL was significantly lower than the blood PVL. The blood PVL showed a significant correlation with serum antibody titer, colostrum PVL, and colostral antibody titer. However, there were no major correlations between the serum and colostral antibody titers.

CONCLUSIONS

This is the first report investigating the temporal changes in colostral antibody titer in terms of inhibiting BLV infection in vitro. The results of antibody detection by Syncytium-induction Inhibition Assay suggested that the protective activity of the colostral antibodies against BLV infection would be conferred by anti-BLV gp51 antibody. The high antibody titer of colostral whey suggests that colostral whey could be a potential source of antibodies with a low risk of infection in neonatal calves.

Effects of pegbovigrastim administration on periparturient diseases, milk production, and reproductive performance of Holstein cows

The aim of this study was to evaluate the effects of treating Holstein cows with pegbovigrastim on periparturient diseases, milk production, and reproductive performance while exploring the mode of action of an immunomodulatory protein. Cows were randomly allocated to 1 of 2 treatments, untreated control (CTR, n = 423) and pegbovigrastim (PEG, n = 417). At 7 d from the anticipated calving date (d -7), cows allocated to PEG received a subcutaneous injection of 15 mg of pegylated recombinant bovine granulocyte colony stimulating factor (pegbovigrastim injection, Imrestor, Elanco Animal Health, Greenfield, IN). A second injection was administered within 24 h after calving (d 0). Blood samples were obtained from a subset of cows (CTR, n = 103; PEG, n = 102) at -7 and 0, 3, 7, and 14 d relative to parturition. Samples were used for hemogram and quantification of haptoglobin, nonesterified fatty acids, β-hydroxybutyrate, and trace and macro minerals. Vaginal cytobrush was performed on the same subset cows at d 0, 7, and 14 to assess the relative neutrophil count. Additionally, colostrum samples were collected to measure IgG, IgM, IgA, and lactoferrin concentrations. Postpartum disease occurrence was recorded from calving until 30 d in milk (DIM). Weekly milk yield was recorded for the first 12 wk after calving. Cows treated with PEG had a 3- to 4-fold increase in circulating polymorphonuclear leukocyte, lymphocyte, and monocyte numbers, with a peak at 3 d after treatment followed by a gradual decline, but the counts remained significantly greater compared with CTR at 14 DIM. The administration of PEG did not affect the incidence of clinical and subclinical mastitis, retained fetal membranes, metritis, puerperal metritis, and endometritis. Primiparous cows treated with PEG tended to have lower odds of developing hyperketonemia than CTR [odds ratio (OR) = 0.57, 95% confidence interval (CI) = 0.23 to 1.42]. Cows treated with PEG had higher odds of being diagnosed with lameness within 30 DIM compared with CTR (OR = 1.79, 95% CI = 1.16 to 2.76); however, we found no significant differences by 60 DIM. Treatment with PEG increased the odds of displaced abomasum (OR = 8.27, 95% CI = 1.02 to 66.6). Cows treated with PEG had higher odds of being diagnosed with 1 or more clinical diseases compared with CTR cows (OR = 1.39, 95% CI = 1.02 to 1.90). We observed no differences in linear scores or milk composition between treatments. Furthermore, primiparous cows treated with PEG produced more milk than CTR primiparous cows during the first 12 wk postpartum (PEG = 37.51 ± 0.66; CTR = 35.91 ± 0.65 kg), but no differences were observed on energy-corrected milk. Treatment did not alter reproductive performance; additionally, cows diagnosed with metritis or puerperal metritis and treated with PEG tended to have higher proportion of neutrophils in the vaginal mucosa when compared with CTR metritic cows. Although PEG treatment increased circulating polymorphonuclear leukocyte, monocyte, and lymphocyte numbers, as expected, it was detrimental to cow health because it increased morbidity.

Evaluation of the natural vertical transmission of Theileria orientalis

Bovine theileriosis, caused by Theileria orientalis, is endemic from East Asia to Oceania. Even though the disease is mainly transmitted by Haemaphysalis ticks, the T. orientalis parasite can also be transmitted vertically. To develop proper control measures, the frequency of each transmission route must be elucidated. However, the frequency of vertical transmission, including transplacental transmission, of T. orientalis in naturally infected cattle is still controversial. This study aimed to clarify the frequency of the vertical transmission of T. orientalis in naturally infected cattle. Blood samples were collected from 204 T. orientalis-infected dams and their 211 newborn calves (including 7 sets of twins) within the first 24 h as well as 30 days after birth. Furthermore, 31 and 24 calves born to T. orientalis-infected and uninfected dams, respectively, were continuously surveyed for infection until 5 months of age. A total of 5 (2.4%) dams were diagnosed with mild anemia, whereas most of the dams were asymptomatic based on hematological examination and clinical signs. PCR analysis was performed on whole blood to determine the presence of T. orientalis in calves, and no calves were PCR positive 0 and 30 days after birth. However, 9.6% and 0% of the calves born to T. orientalis-infected and uninfected dams, respectively, tested positive at 3 and 5 months of age. The sampled calves were fed in-house, and the survey was conducted during the cold season; thus, horizontal transmission through blood-sucking insects rarely occurred. Therefore, the vertical transmission of T. orientalis took as long as 3 months to become detectable by PCR and occurred in approximately 10% of field cattle.

Hematology reference intervals for adult cows in France using the Sysmex XT-2000iV analyzer

In order to develop bovine hematology reference intervals (RIs) in accordance with new international recommendations, we analyzed 156 blood specimens of healthy adult dairy and beef cows from 32 farms with a Sysmex XT-2000iV analyzer, and by manual scoring of platelet clumps and white blood cell (WBC) differential. We established RIs by the nonparametric method, and examined effects of age, production type (beef vs. dairy), and stage of lactation. RIs could not be determined for platelet count and indices because clumps were observed in 80% of specimens. Optical and impedance red blood cell (RBC) counts were similar, although statistically different. RIs for analyzer and manual WBC differentials were not different except for lymphocyte concentration, the subpopulations of which were counted manually. Hematocrit was higher in beef than dairy cattle, and hemoglobin was lower in early lactation. Increases in RBC count, mean corpuscular volume, mean corpuscular hemoglobin, and RBC distribution width were noted with increasing age, along with decreases in WBC count, neutrophils, and lymphocytes. Most RIs in our study, with the exception of neutrophils, were similar to those previously reported using a flow cytometry analyzer.

Bovine neutrophils in health and disease

Bovine neutrophils have similarities to those of other species with respect to mechanisms of their activation and migration into tissue, modulation of immune responses and the balance between microbial killing and host tissue damage. However, bovine neutrophils have biochemical and functional differences from those of other species, which may yield insights about the comparative biology of neutrophils. Neutrophils play protective and harmful roles in the infectious diseases of cattle that occur at times of transition: respiratory disease in beef calves recently arrived to feedlots and mastitis and other diseases of postparturient dairy cows. An important research focus is the mechanisms by which risk factors for these diseases affect neutrophil function and thereby lead to disease and the prospect of genetic or pharmacologic improvement of disease resistance. Further, in keeping with the One Health paradigm, cattle can be considered a model for studying the role of neutrophils in naturally occurring diseases caused by host-adapted pathogens and are thus an intermediary between studies of mouse models and investigations of human disease. Finally, the study of bovine neutrophils is important for agriculture, to understand the pathogenesis of these production-limiting diseases and to develop novel methods of disease prevention that improve animal health and reduce the reliance on antimicrobial use.

Effect of adding clay with or without a Saccharomyces cerevisiae fermentation product on the health and performance of lactating dairy cows challenged with dietary aflatoxin B1

The study was conducted to examine the effect of supplementing bentonite clay with or without a Saccharomyces cerevisiae fermentation product (SCFP; 19 g of NutriTek + 16 g of MetaShield, both from Diamond V, Cedar Rapids, IA) on the performance and health of dairy cows challenged with aflatoxin B₁ (AFB₁). Twenty-four lactating Holstein cows (64 ± 11 d in milk) were stratified by parity and milk production and randomly assigned to 1 of 4 treatment sequences. The experiment had a balanced 4 × 4 Latin square design with 6 replicate squares, four 33-d periods, and a 5-d washout interval between periods. Cows were fed a total mixed ration containing 36.1% corn silage, 8.3% alfalfa hay, and 55.6% concentrate (dry matter basis). Treatments were (1) control (no additives), (2) toxin (T; 1,725 µg of AFB₁/head per day), (3) T + clay (CL; 200 g/head per day; top-dressed), and (4) CL+SCFP (CL+SCFP; 35 g/head per day; top-dressed). Cows were adapted to diets from d 1 to 25 (predosing period) and then orally dosed with AFB₁ from d 26 to 30 (dosing period), and AFB₁ was withdrawn from d 31 to 33 (withdrawal period). Milk samples were collected twice daily from d 21 to 33, and plasma was sampled on d 25 and 30 before the morning feeding. Transfer of ingested AFB₁ into milk aflatoxin M₁ (AFM₁) was greater in T than in CL or CL+SCFP (1.65 vs. 1.01 and 0.94%, respectively) from d 26 to 30. The CL and CL+SCFP treatments reduced milk AFM₁ concentration compared with T (0.45 and 0.40 vs. 0.75 µg/kg, respectively), and, unlike T, both CL and CL+SCFP lowered AFM₁ concentrations below the US Food and Drug Administration action level (0.5 µg/kg). Milk yield tended to be greater during the dosing period in cows fed CL+SCFP compared with T (39.7 vs. 37.7 kg/d). Compared with that for T, plasma glutamic oxaloacetic transaminase concentration, indicative of aflatoxicosis and liver damage, was reduced by CL (85.9 vs. 95.2 U/L) and numerically reduced by CL+SCFP (87.9 vs. 95.2 U/L). Dietary CL and CL+SCFP reduced transfer of dietary AFB₁ to milk and milk AFM₁ concentration. Only CL prevented the increase in glutamic oxaloacetic transaminase concentration, and only CL+SCFP prevented the decrease in milk yield caused by AFB₁ ingestion.

Hematology reference intervals for neonatal Holstein calves

Data regarding hematologic reference intervals (RI) for neonatal calves have not been published yet. The aims of this study were: a) to establish hematology RIs for neonatal Holstein calves, b) to compare them with the RIs for lactating cows, and c) to investigate the relationship of age and gender with the hematologic profile of calves. Two-hundred and fifty-four clinically healthy Holstein calves (1-9days old, from 30 farms) and 82 healthy Holstein cows (between 30 and 150days in milk, from 10 farms) were blood sampled once for a complete blood count evaluation, using the ADVIA 120 hematology analyzer. An additional blood sample was collected from each calf for serum total protein concentration measurement. RIs and age-related RIs were calculated with the Reference Value Advisor freeware. Comparisons between calves and cows and between male and female calves were performed with t-test or Mann-Whitney test. Red blood cell count (RBC), white blood cell count (WBC), neutrophil, lymphocyte and platelet counts in calves were higher, while mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were lower than in cows. Lymphocyte and platelets showed a notable increase through age. Finally, female calves had higher RBC, hematocrit and hemoglobin concentration than males. Age-specific RIs should be used for the interpretation of the complete blood count in Holstein calves.

Recombinant bovine somatotropin on heifer’s biometric measures, bodyweight, blood metabolites, and dry matter intake predictions

This study aimed to determine the influence of sustained-release recombinant bovine somatotropin (rbST) injections on biometrics measures, bodyweight (BW), average BW gain, observed and predicted DM intake, accuracy of recent methods to estimate DM intake, blood metabolites, haematological profile and rectal temperature in dairy heifers. Thirty Holstein heifers (132 ± 27 kg BW and 6.2 ± 0.35 months of age) were used in a complete randomised design experiment. Heifers were assigned to treatments: (1) Control (CON), 250 mL of saline solution, or (2) rbST, 250 mg of sustained-release rbST every 15 days. Treatments were injected in the subcutaneous of ischiorectal fossa or subscapular region in a regular alternating manner (right and left side) every 15 days throughout a period of 90 days. Prediction of DM intake was calculated using either non-linear or linear models for heifers in tropical conditions. rbST injections increased the average values of thoracic perimeter, length, and rump width in heifers. rbST-treated heifers had higher average BW and BW gain than CON. Regardless of the model applied, both observed and predicted DM intake were higher for heifers rbST-treated in relation to CON. Non-linear model was accurate without significant bias. rbST injections elevated blood glucose and high-density lipoprotein cholesterol concentration in heifers. No differences were detected on haematological profile and rectal temperature of heifers. rbST injections every 15 days to growing heifers promoted animal performance by increasing biometrics measures and BW gain. In addition, non-linear model was accurate to predict DM intake of heifers.

Reference intervals for hematological and biochemical parameters, acute phase proteins and markers of oxidation in Holstein dairy cows around 3 and 30days after calving

The establishment of specific reference intervals (RIs) is advisable when different metabolic conditions in the patient population are present or when existing RIs are not suitable. Holstein dairy cows, at the start of lactation, experience a negative energy balance and an altered immune function that can lead to different levels of blood parameters compared with cows at peak lactation. The aim of this study was the determination of RIs for Holstein cows at 3±1 and 30±3days in milk. To this aim, 145 cows, from 4 herds, were sampled. A wide panel of hematological and biochemical analytes was determined, as well as the measurement of markers of inflammation/oxidation. RIs were generated following the American Society of Veterinary Clinical Pathology (ASVCP) guidelines and the effects of lactation period, parity, herd and day of sampling were determined. Data from 39 out of 52 analytes were significantly different according to lactation period. Data of 13 out of 52 analytes were not significantly different between the two groups. Some differences were also recorded between herds and parity groups but the adoption of specific RIs for these subgroups, however, has practical limitations. In conclusion the use of RIs specific for the lactation period is highly justified from both a statistical and a biological point of view. Pre-analytical factors associated with parity or management need to be considered in the evaluation of results of some analytes.

Evaluation of arterial digital blood flow using Doppler ultrasonography in healthy dairy cows

BACKGROUND

Local circulatory disturbances have been implicated in the development of foot disorders in cattle. The goals of this study were to evaluate the suitability of the interdigital artery in the pastern region in both hind limbs using pulsed-wave (PW) Doppler ultrasonography and to investigate quantitative arterial blood flow variables at that site in dairy cows. An Esaote MyLabOne ultrasound machine with a 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the pastern region in both hind limbs of 22 healthy German Holstein cows. The cows originated from three commercial farms and were restrained in a standing hoof trimming chute without sedation.

RESULTS

A PW Doppler signal suitable for analysis was obtained in 17 of 22 cows. The blood flow profiles were categorised into four curve types, and the following quantitative variables were measured in three uniform cardiac cycles: vessel diameter, pulse rate, maximum systolic velocity, maximum diastolic velocity, end-diastolic velocity, reverse velocity, maximum time-averaged mean velocity, blood flow rate, resistance index and persistence index. The measurements did not differ among cows from the three farms. Maximum systolic velocity, vessel diameter and pulse rate did not differ but other variables differed significantly among blood flow profiles.

CONCLUSIONS

Differences in weight-bearing are thought to be responsible for the normal variability of blood flow profiles in healthy cows. The scanning technique used in this report for evaluation of blood flow in the interdigital artery appears suitable for further investigations in healthy and in lame cows.

Evaluation of arterial digital blood flow using Doppler ultrasonography in healthy dairy cows

BACKGROUND

Local circulatory disturbances have been implicated in the development of foot disorders in cattle. The goals of this study were to evaluate the suitability of the interdigital artery in the pastern region in both hind limbs using pulsed-wave (PW) Doppler ultrasonography and to investigate quantitative arterial blood flow variables at that site in dairy cows. An Esaote MyLabOne ultrasound machine with a 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the pastern region in both hind limbs of 22 healthy German Holstein cows. The cows originated from three commercial farms and were restrained in a standing hoof trimming chute without sedation.

RESULTS

A PW Doppler signal suitable for analysis was obtained in 17 of 22 cows. The blood flow profiles were categorised into four curve types, and the following quantitative variables were measured in three uniform cardiac cycles: vessel diameter, pulse rate, maximum systolic velocity, maximum diastolic velocity, end-diastolic velocity, reverse velocity, maximum time-averaged mean velocity, blood flow rate, resistance index and persistence index. The measurements did not differ among cows from the three farms. Maximum systolic velocity, vessel diameter and pulse rate did not differ but other variables differed significantly among blood flow profiles.

CONCLUSIONS

Differences in weight-bearing are thought to be responsible for the normal variability of blood flow profiles in healthy cows. The scanning technique used in this report for evaluation of blood flow in the interdigital artery appears suitable for further investigations in healthy and in lame cows.

Reference ranges of hematology and lymphocyte subsets in healthy Korean native cattle (Hanwoo) and Holstein dairy cattle

There are no accurate reference ranges for hematology parameters and lymphocyte subsets in Korean native beef cattle (Hanwoo). This study was performed to establish reliable reference ranges of hematology and lymphocyte subsets using a large number of Hanwoo cattle (n = 350) and to compare differences between Hanwoo and Holstein dairy cattle (n = 334). Additionally, age-related changes in lymphocyte subsets were studied. Bovine leukocyte subpopulation analysis was performed using mono or dual color flow cytometry. The leukocyte subpopulations investigated in healthy cattle included: CD2(+) cells, sIgM(+) cells, MHC class II(+) cells, CD3(+) CD4(+) cells, CD3(+) CD8(+) cells, and WC1(+) cells. Although Hanwoo and Holstein cattle are the same species, results showed several differences in hematology and lymphocyte subsets between Hanwoo and Holstein cattle. This study is the first report to establish reference ranges of hematology and lymphocyte subsets in adult Hanwoo cattle.

Reference intervals in avian and exotic hematology

Historically, reference intervals (RI) have come from many sources and been generated by several methods and sample sizes. As RI generation has matured in human laboratory medicine, important guidelines have been adopted in veterinary medicine. Although meeting the goals of these guidelines may be difficult, especially with avian and exotic species, sets of 20 to 40 samples can be used with proper statistical calculations, and other viable alternatives have been examined. The adoption and knowledge of these different methods are important to make a positive move forward in RI generation for special species.

Natural Besnoitia besnoiti infections in cattle: hematological alterations and changes in serum chemistry and enzyme activities

Background

The emerging disease bovine besnoitiosis is caused by the apicomplexan parasite Besnoitia besnoiti. Clinical signs of acute besnoitiosis are pyrexia, anorexia and subcutaneous edema. In subacute and chronic besnoitiosis parasitic cysts arise in a variety of tissues and affected cattle display skin lesions and weight loss. In all stages of bovine besnoitiosis, lesions can be found in many organ systems and therefore presumably alter a variety of laboratory parameters. In this study, the impact of naturally acquired acute, subacute and chronic bovine besnoitiosis on hematologic parameters, serum chemistry, and enzyme activities was investigated. Laboratory parameters of two Simmental heifers and two Limousin cows were monitored during acute, subacute and chronic besnoitiosis and in another Simmental heifer during subclinical besnoitiosis. To determine aberrations of laboratory parameters, values were compared with reference ranges obtained from B. besnoiti negative Simmentals (224 samples of nine animals) and Limousins (41 animals). Further, laboratory parameters of B. besnoiti seropositive Limousin cows (54 animals; 32 of these showing clinical signs) and healthy B. besnoiti seronegative Limousin cows (41 animals) were compared.

Results

During acute and subacute besnoitiosis, a reduction of leukocyte and erythrocyte concentrations, hematocrit, serum albumin, urea, magnesium, and calcium concentrations were observed. Serum total protein, globulin, total bilirubin and creatinine concentrations were increased and aspartate transaminase (AST) and creatine kinase (CK) activities were elevated. In chronic besnoitiosis, erythrocyte parameters were statistically significantly lower, and total protein and globulin concentrations were significantly higher in B. besnoiti seropositive compared with B. besnoiti seronegative Limousin cows.

Conclusions

In this study, altered laboratory parameters during the course of naturally acquired acute, subacute and chronic bovine besnoitiosis are described for the first time. Only a few animals were examined in acute and subacute besnoitiosis, however the alterations of laboratory parameters during these stages reflected i) the acute inflammatory state (e.g. high levels of serum globulin fractions), ii) clinical findings such as disturbed condition (e.g. bilirubin concentrations), and iii) lesions such as muscle necroses described in the literature (e.g. AST or CK activities). Chronic besnoitiosis led to typical alterations of chronic inflammatory diseases like hyper-(gamma)-globulinemia or reduced erythrocyte concentrations.

Perfil hematológico e bioquímico de búfalos ( Bubalus bubalis ) na Amazônia Oriental

Resumo: O hemograma e as dosagens bioquímicas são exames rotineiramente utilizados na avaliação da saúde dos animais domésticos, incluindo os búfalos. Na região Amazônica pesquisas nessa temática ainda são escassas. Desta forma, o objetivo deste trabalho foi estabelecer intervalos de referência para hematologia e bioquímica sanguínea de Bubalus bubalis criados na Amazônia Oriental e avaliar os efeitos da idade e do sexo sobre os valores bioquímicos e hematológicos obtidos. Foram utilizados 73 animais da raça Murrah, divididos em três grupos, o grupo 1 (G1, n=22) com animais de dois a oito meses, grupo 2 (G2, n=23) com animais de nove a dois anos e o grupo 3 (G3, n=28) com animais com mais de dois anos. Os hemogramas e as análises bioquímicas foram realizados em equipamentos automatizados. Os intervalos de referência foram estabelecidos conforme as recomendações do Clinical and Laboratory Standards Institute (CLSI). Para avaliar o efeito do sexo e da idade foram utilizados os testes de Tukey, e Kruskal-Wallis, sendo as diferenças consideradas significativas quando P<0,05. Houve influencia da idade sobre os valores de hemácias (He), hematócrito (Ht), hemoglobina (Hb), leucócitos, linfócitos, eosinófilos, neutrófilos, plaquetas, volume plaquetário médio (VPM), índices hematimétricos (Volume Globular Média - VGM, Hemoglobina Corpuscular Média - HCM, e Coeficiente de variação eritrocitário - RDW) e relação neutrófilo:linfócito (N:L). O sexo influenciou o valor do VGM e do índice de amplitude de distribuição do tamanho da plaqueta (PDW) que foram maiores (P<0,05) nas fêmeas, enquanto o RDW foi maior nos machos. Na comparação dos parâmetros bioquímicos entre as faixas etárias, verificou-se que a idade influenciou a atividade das enzimas aspartato aminotransferase (AST) e fosfatase alcalina (FA) e as concentrações de creatinina, proteínas totais e bilirrubina direta. As concentrações de creatinina e bilirrubina direta foram significativamente maiores nos animais da maior faixa etária. O sexo influenciou a atividade da AST e a concentração de bilirrubina direta, que foram maiores (P<0.05) nos machos. Os valores hematológicos e bioquímicos estabelecidos podem ser utilizados como referência para búfalos criados na Amazônia Oriental.

Hematology as a diagnostic tool in bovine medicine

The objective of the current review is to provide the reader with an overview of the bovine hematological profile. Sample collection, bovine reference ranges, and cattle-specific characteristics of erythrocyte, leukocyte, and platelet parameters are reviewed. Furthermore, diseases associated with abnormalities in the complete blood cell count of cattle are discussed.