Risk factors for herd-level bovine-tuberculosis seropositivity in transhumant cattle in Uganda

We investigated the prevalence and risk factors to positive herd-level tuberculin reactivity between October 2003 to May 2004 to bovine tuberculosis (BTB) in the four transhumant districts of Uganda: three districts (Karamoja region) of nomadic transhumance cattle rearing (30 superherds and 1522 cattle), and one district (Nakasongola) of fixed-transhumance (7 herds and 342 cattle). We used the comparative intradermal skin-test, sampled 50 animals per superherd/herd, and considered herd positive if there was at least one reactor. Of the 30 superherds under nomadic transhumance, 60% (95% CI 41.4, 79) were tuberculin-test positive; of the 7 fixed herds, 14.3% (95% CI −20.7, 49.2) were tuberculin test positive. The true herd prevalence was estimated at 46.6%. Many risk factors were collinear. The final multivariable logistic-regression model included: recent introductions from market (OR = 3.4; 95% CI 1.1, 10.3), drinking water form mud holes during dry season (OR = 49; 95% CI 9.1, 262), and the presence of monkeys (OR = 0.08; 95% CI 0.0, 0.6) or warthogs (OR = 0.1; 95% CI 0.0, 0.3). No association was found between herd size or number of herd contacts with reactors; it was probably masked by the effect of high between-herd interactions. Provision of water from mud holes in dry river beds and introductions of new animals are risk factors that might be targeted to control BTB in transhumance areas.     

Analysis of risk factors associated with bovine leukemia virus seropositivity within dairy and beef breeding farms in Japan: A nationwide survey

This cross-sectional study evaluated risk factors associated with farm-level bovine leukemia virus (BLV) seropositivity in 563 dairy and 490 beef farms throughout Japan. Twenty randomly selected cattle on each farm were serologically tested, and farm epidemiologiocal information was obtained through face-to-face interviews. Due to the large number of zero-prevalence dairy and beef farms, data analysis was performed using a zero-inflated negative binomial model, which revealed that the common risk factors associated with higher within-farm seroprevalence were past detection of clinical leukemia and presence of blood-sucking insects. Loose housing on dairy farms and direct contact between calves and adult cattle on beef farms were also identified as risk factors. With regard to farm-level presence of BLV, the presence of purchased cattle was found to be a risk factor in both sectors. Sending heifers to a common ranch was identified as an additional risk factor for dairy farms.     

Risk factors for metritis in Danish dairy cows

A retrospective longitudinal study of metritis was conducted in Denmark on data collected during 1993-1994. Data on herd size, breed, parity, and treatment of disease were obtained from the Danish Cattle Database. Management and production-facility data were collected using a questionnaire, conducted as a telephone interview in 1994. The study included 2144 herds from three regions in Denmark (102,060 cows). Herd-level variables included were: herd size, housing, flooring, grazing, calving measures, and calving supervision. Cow-level variables were: parity, breed, calving season and whether the cow had been treated by a veterinarian for dystocia or the diseases: retained placenta, reproductive disease, ketosis, milk fever, or dry cow mastitis.Marginal multivariable logistic-regression analyses were performed. The cow with highest odds of metritis was a first or greater than or equal to third parity cow, of large breed, that calved during November-April, in a zero-grazing herd. The cow had been treated for dystocia, retained placenta, and at least one other reproductive disease, but not for ketosis.     

Estimation of the age-dependent risk of infection to BSE of dairy cattle in Great Britain

An important aspect of the bovine spongiform encephalopathy (BSE) epidemic has been an apparent age-dependent risk of infection, with younger cattle being more likely to become infected than older cattle. Our objective was to determine the age-dependent risk of infection of dairy cattle. We first reviewed unpublished data on the feeding patterns of proprietary concentrates for dairy-replacement cattle. These data showed that autumn- and spring-born cattle would receive different feeding patterns of proprietary concentrates, and so age-dependent risk of infection profiles were obtained separately for autumn- and spring-born cattle. We used back-calculation methods to analyse BSE-epidemic data collected in Great Britain between 1984 and 1996.

Dairy cattle were most at risk in the first 6 months of life; adult cattle were at relatively low risk of infection. Between 6 and 24 months of age, risk profiles reflected feeding patterns of proprietary concentrates in each of the autumn- and spring-born cohorts.     

Updated prediction for the BSE epidemic in dairy cattle in Japan

Following the detection of the first case of Bovine spongiform encephalopathy (BSE) in Japan in September 2001, nine million cattle were tested for BSE up to the end of 2008. As a result, a further 28 cases were detected in dairy cattle. Using the mathematical model previously developed and surveillance data up to the end of 2008, we estimated the prevalence of BSE-infected animals within each birth cohort for the years 1995–2001. We predicted historic and future trends in the number of BSE-infected animals to be culled and anticipated BSE cases from each birth cohort. The results indicate that more infected animals (428 (95% CI: 59–727)) than previously estimated would have been culled from 1995 to 2001, and more cases (53 (95% CI: 25–101)) than previously predicted would have been detected during this period with a higher peak in 2001, if a BSE surveillance program as comprehensive as the present one was applied. In and after 2009, 0–2 cases of BSE would likely to be detected. As previously predicted, the BSE epidemic should be eradicated by 2012.     

Dynamics of infection and immunity in a dairy cattle population undergoing an eradication programme for Infectious Bovine Rhinotracheitis (IBR)

Several countries within the European Union (EU) have successfully eradicated Infectious Bovine Rhinotracheitis (IBR), while others (e.g. Germany) are making efforts to achieve IBR-free status. EU member states IBR eradication programmes must meet Community legislation requirements that ban breeding farms from purchasing positive animals, from using whole-virus IBR vaccines, and from inseminating cows with semen from positive bulls. A follow-up study from 2002 to 2005 was carried out in the province of Trento (Italy), where a compulsory programme for IBR eradication was started in 1998. IBR outbreaks (identified on the basis of seroconversion of sentinel animals) were concentrated in larger positive herds. A higher incidence was recorded between 2003 and 2004. An association between markedly high temperatures in the summer of 2003 and virus reactivation has been suggested but is yet to be confirmed. The practice of driving cattle to common alpine pastures for the summer season did not play a significant epidemiological role in IBR transmission. Premising that only seronegative animals are allowed to enter dairy farms, animal movement increases the infection risk to a moderate extent. The long-term persistence of IBR antibodies was more pronounced in animals positive for antibodies to the glycoprotein E (gE). Scattered seroconversions, occurring mostly in positive herds, require careful interpretation in order to avoid overestimating the incidence of the infection at herd level.     

Risk factors of bovine tuberculosis in cattle in rural livestock production systems of Ethiopia

This study shows a representative stratified cluster sample survey of the prevalence of comparative intradermal tuberculin test in cattle from four regions in Ethiopia. Using a cut-off for positivity of 2 mm, it assesses possible risk factors for tuberculin-positive reaction in cattle. Seventy-three villages in 24 kebeles (administrative units) were randomly selected, from which 2216 cattle from 780 owners were tested. In addition, 450 of these cattle owners were interviewed for risk factor assessment. Ninety-nine percent of the tested cattle in this rural livestock production system were traditional zebus. The individual overall prevalence of cattle bovine tuberculosis (BTB)e was 3%, with the highest found in Meskan Mareko, in Central Ethiopia (7.9%) and the lowest in Woldia, in the North East edge of the Rift Valley (1.2%). Generalised Linear Mixed Models (GLMM) with random effect on kebeles was used to analyse risk factors of cattle reactors and human tuberculosis (TB) infection. Purchase of cattle and presence of other livestock in the herd were statistically significant, with OR: 1.7, p-values of 0.03 and OR: 2, p = 0.05, respectively. Family members diagnosed with TB or showing clinical signs of extra-pulmonary TB (EPTB) were reported in 86 households (19%). None of the assessed potential risk factors of disease transmission between cattle and human (food consumption, livestock husbandry and presence of BTB-positive cattle) were statistically significant.     

Prevalence and risk factors associated with bovine viral diarrhea virus infection in dairy herds in Jordan

A cross-sectional study was carried out to determine the seroprevalence and to identify risk factors associated with bovine viral diarrhea virus (BVDV) infection in 62 non-vaccinated dairy herds (671 cows) in Jordan between January and June 2007. Information regarding herd management was recorded through a personal interview with farmers. Antibodies against BVDV were detected using an indirect ELISA test. Chi-square analysis and multivariable logistic regression model were used to identify risk factors for BVDV seropositivity. The true prevalence of antibodies against BVDV in individual cows and cattle herds was 31.6% and 80.7%, respectively. The seroprevalence of BVDV in medium and large size herds was significantly higher than that in smaller herds. There was no significant difference in BVD seroprevalence between different age groups. Random-effects logistic regression model revealed two major factors associated with seropositivity to BVDV; exchange of visits between adjacent farm workers and not isolating newly purchased animals before addition to the herd. The seroprevalence of BVDV in cows located in the northern Jordanian governorates was significantly higher than that in other studied governorates. Results of this study indicated that BVDV is highly prevalent in Jordan and BVDV infection could be controlled by livestock-trade control, and applying strict biosecurity measures in the dairy farms.     

Risk factors for bovine respiratory disease in Australian feedlot cattle: Use of a causal diagram-informed approach to estimate effects of animal mixing and movements before feedlot entry

A nationwide longitudinal study was conducted to investigate risk factors for bovine respiratory disease (BRD) in cattle in Australian feedlots. After induction (processing), cattle were placed in feedlot pens (cohorts) and monitored for occurrence of BRD over the first 50 days on feed. Data from a national cattle movement database were used to derive variables describing mixing of animals with cattle from other farms, numbers of animals in groups before arrival at the feedlot, exposure of animals to saleyards before arrival at the feedlot, and the timing and duration of the animal's move to the vicinity of the feedlot. Total and direct effects for each risk factor were estimated using a causal diagram-informed process to determine covariates to include in four-level Bayesian logistic regression models. Mixing, group size and timing of the animal's move to the feedlot were important predictors of BRD. Animals not mixed with cattle from other farms prior to 12 days before induction and then exposed to a high level of mixing (≥4 groups of animals mixed) had the highest risk of developing BRD (OR 3.7) compared to animals mixed at least 4 weeks before induction with less than 4 groups forming the cohort. Animals in groups formed at least 13 days before induction comprising 100 or more (OR 0.5) or 50–99 (OR 0.8) were at reduced risk compared to those in groups of less than 50 cattle. Animals moved to the vicinity of the feedlot at least 27 days before induction were at reduced risk (OR 0.4) compared to cattle undergoing short-haul transportation (<6 h) to the feedlot within a day of induction, while those experiencing longer transportation durations (6 h or more) within a day of induction were at slightly increased risk (OR 1.2). Knowledge of these risk factors could potentially be used to inform management decisions to reduce the risk of BRD in feedlot cattle.     

Apparent seroprevalence,isolation and identification of risk factors for brucellosis among dairy cattle in Goa,India

Brucellosis is a highly contagious zoonotic infection affecting livestock and human beings. The disease has been reported worldwide except in few countries where it has been eradicated. The prevalence of brucellosis among cattle from 11 farms having a history of abortions was studied. A total of 481 samples comprising of blood, milk, vaginal swabs, vaginal discharges, placental tissues and fetal tissues were collected from 296 animals. Clinical samples were processed for the isolation of Brucella. Serum samples (n = 296) were tested by Rose Bengal Plate Test (RBPT) and indirect ELISA. A total of 90 (30.40%) and 123 (41.55%) samples were positive by RBPT and indirect ELISA, respectively. Also 27.02% samples were positive by both the tests. Brucella isolates (n = 8) were recovered from clinical samples using Brucella selective media. All the isolates demonstrated PCR amplification for the bcsp31 and IS711 genes. Amplification of Brucella abortus specific primer was demonstrated by all the isolates in AMOS PCR indicating isolates to be of either B. abortus biotype 1, 2 or 4. Risk factors for transmission of brucellosis among cattle population were studied by field surveys. It was observed that lack of awareness about brucellosis (OR = 8.739, P = 0.138) and inadequate floor space (OR = 0.278, P = 0.128) were crucial risk factors for transmission of bovine brucellosis.     

Evaluation of variation in serum globulin concentrations in dairy cattle

BACKGROUND: Several factors may influence the concentration of serum globulins in healthy cows and thereby affect clinical interpretation; however, few studies have addressed sources of variation in globulin values. OBJECTIVES: The purpose of this study was to compare colorimetry-based total serum globulin values with electrophoretically-determined serum globulin fractions and with IgG concentration, and to evaluate diurnal and long-term physiological variation and the effects of lactation and venipuncture site on serum globulin concentrations in Holstein dairy cattle. METHODS: Serum total globulin and albumin concentrations were analyzed by colorimetry and electrophoresis in 86 lactating cows; IgG concentrations were determined by radial immunodiffusion in 41 dry and 34 lactating cows. Serum globulins were analyzed hourly for 24 hours in 8 lactating cows and weekly for 15 weeks in 6 additional cows. Globulin concentrations were compared in samples obtained from jugular and coccygeal venipuncture sites in 4 cows. Results were analyzed using parametric statistical tests. RESULTS: Colorimetry-based total serum globulin concentrations correlated well with gamma-globulin fractions (r2 = 0.87) and IgG concentrations (r2 = 0.91). Diurnal variation of total serum globulins concentration was significant (P =.01); however, globulins did not vary significantly over a 15-week period. Mean serum globulins concentration in samples obtained from the jugular vein was 2.35 g/L higher than that in samples obtained by coccygeal venipuncture (P <.0001). CONCLUSIONS: The colorimetric method used widely in routine laboratory analyses remains a useful test for globulins determination in dairy cattle. However, time of sampling and venipuncture site should be considered in the interpretation of serum globulins on serial or interindividual specimens.     

Risk factors for smallholder dairy cattle mortality in Tanzania

A retrospective cross-sectional study of mortality was conducted on smallholder dairy farms in 2 separate regions (Iringa and Tanga) of Tanzania during the period of January to April 1999. A total of 1789 cattle from 400 randomly sampled smallholder dairy farms (200 each from Iringa and Tanga regions) were included in the study. These animals contributed a total risk period of 690.4 and 653.95 years for Tanga and Iringa, respectively. The overall mortality rates were estimated to be 8.5 and 14.2 per 100 cattle years risk for Tanga and Iringa regions, respectively; 57.7% of the reported deaths were of young stock less than 12 months old; 45% of reported young stock deaths (< or = 12 months old) were due to tickborne diseases, mainly East Coast Fever (ECF) and anaplasmosis. Disease events including ECF were reported to occur in all months of the year. Survival analysis using Cox proportional hazard models indicated that, in both regions, death rate and risk was higher in young stock less than 12 months than in older animals (relative risk RR = 4.92, P < 0.001 for Iringa; RR = 5.03 P = 0.005 for Tanga). In the Tanga region reported mortality rates were significantly higher for male animals (RR = 3.66, P = 0.001) and F2 compared with F1 animals (RR = 3.04, P = 0.003). In the Iringa region, reported mortality rates were lower for cattle on farms where the owner had attended a dairy development project training course (RR = 0.47, P = 0.012). Farms located in Iringa urban district and Pangani were associated with higher risk (mortality risk 21% for Iringa urban and 34% for Pangani). Our findings suggest that timely health and management interventions on these factors are necessary to alleviate losses from disease and emphasise that understanding variation in mortality risk within a population can enhance early response to potential outbreaks, reducing losses.     

Distribution and environmental risk factors for paratuberculosis in dairy cattle herds in Michigan.

OBJECTIVE: To determine prevalence of paratuberculosis among dairy cattle herds and to identify associated soil-related risk factors. SAMPLE POPULATION: Serum and soil samples for 121 Michigan dairy herds. PROCEDURE: Blood samples were collected from cows at each farm and tested for Mycobacterium paratuberculosis, using an antibody ELISA. Soil samples were collected from pastures and exercise lots; pH and available iron content were determined. A questionnaire was administered to collect data regarding farm management practices and productivity. RESULTS: 55% of the herds tested had > or = 2 M paratuberculosis-positive cattle. Adjusting sample prevalence for distribution of herd size strata yielded a statewide herd prevalence of 54%. Of 3,886 cattle tested, 267 had positive results. Prevalence of test-positive cattle was 6.9%. For every part per million (ppm) increase in soil iron content, there was a 1.4% increase in the risk of a herd being test-positive. An increase in soil pH of 0.1 was associated with a 5% decrease and an increase in soil iron content of 10 ppm was associated with a 4% increase in the number of test-positive cattle. Application of lime to pasture areas was associated with a herd being only 10% as likely to be paratuberculosis positive and with a 72% reduction in number of test-positive cattle. CONCLUSIONS AND CLINICAL RELEVANCE: Prevalence of paratuberculosis-positive dairy herds in Michigan (54%) was greater than expected, but prevalence of paratuberculosis-positive cattle (6.9%) was within anticipated values. These prevalences were associated positively with acidic soil and increased soil iron content. Application of lime to pasture areas was associated with reduced risk of paratuberculosis.     

Bovine viral diarrhoea virus in beef cattle herds of Yucatan, Mexico: seroprevalence and risk factors

A survey of bovine viral diarrhoea virus (BVDV) infection was carried out from June 2001 to July 2002 in a non-vaccinated beef cattle population from the livestock region of Yucatan, Mexico, to assess seroprevalence and identify risk factors related to seroprevalence. The aim was also to estimate the intra-herd correlation (r_e) and design effect (D) of BVDV seropositivity. Cattle were selected by a two-stage cluster sampling. Blood samples were collected from 560 animals originating from 40 herds. Sera were tested for antibodies against BVDV using an indirect ELISA test. The sensitivity and specificity of the test was 97.9 and 99.7%, respectively. Risk factors regarding the herd and each animal sampled were recorded through a personal interview at the time of blood sampling. Twenty-four of the 40 herds had at least one seropositive animal. The animal true seroprevalence was estimated as 14%. The marginal logistic regression model used to describe the data found a significant (p < 0.05) association of herd size–cow-origin interaction. The interaction was due to a higher risk of seropositivity in the category of herds with ≤100 animals and purchased cows (OR = 1) as compared to herds with ≤100 animals and cows born in the farm (OR = 0.23). Seropositivity between cows purchased and cows born in the farm was similar for herd sizes of 101–196 and >196 animals. The r_e and D values were 0.17 ± 0.05 and 3.16 ± 0.57, respectively.     

Investigations of cattle herd breakdowns with bovine tuberculosis in four counties of England and Wales using VETNET data

Cattle herd breakdown (HBR) with bovine tuberculosis (BTB) was investigated for farms in four counties of England and Wales outside southwest England from 1986 to early 2000. Data from the national database of TB testing history (VETNET) were used. Factors that influenced HBR included calendar time, herd size, number of cattle tested, the test type, the inter-test interval and spatial grouping of farms. Herd tests other than routine herd tests had an increased risk of HBR in all four counties. In all counties, the risk of HBR increased with calendar time and in Shropshire a test interval of 3 years was associated with an increased risk of HBR compared with a 1-year test interval. In Staffordshire and Sussex, a 4-year test interval was associated with a lower risk of HBR compared with a 1-year test interval. There was no evidence of spatial clustering of HBR in West Glamorgan (equal spatial risk in a 15–30 km radius) and weak evidence of spatial clustering in Shropshire (7–15 km) and Sussex (5–10 km). In Staffordshire, there was evidence of spatial (2–4 km) and time (3–4 years) clustering of HBR. The locally increased rate of testing following a confirmed HBR increased the detection of infected herds but did not prevent local spread in two of the four counties (Shropshire and Staffordshire) since the rate of HBR increased linearly from 1988 to 2000. The main conclusion is that there were both local and distant components of spread.     

An operation-level prospective study of risk factors associated with the incidence density of lameness in Michigan (USA) equine operations

A prospective cohort study of lameness in Michigan equids was conducted using the Michigan Equine Monitoring System (MEMS) Phase-II database. MEMS Phase II was an equine health-monitoring study of 138 randomly-selected Michigan equine operations. Management and health-related data were collected for operations in two 12-month periods. The median incidence density of lameness was 2.8 cases per 10000 horse-days at-risk (Minimum = 0; 25th Quartale (Q) = 0; 75th Q = 10.2; Maximum = 48.5). Equine operation-management and environmental risk factors associated with the incidence density of lameness were assessed using multivariable Poisson regression. Management risk factors associated with the incidence density of lameness included the total operation horse-days monitored (3rd Q: Relative Risk (RR) = 0.46; 95% Confidence Interval (CI): 0.29–0.71 and 4th Q: RR = 0.24; 95% CI: 0.16–0.37), the veterinary-related services score (3rd Q: RR = 0.61; 95% CI: 0.39–0.96 and 4th Q: RR = 1.45; 95% CI: 1.01–2.08), the farrier-related services score (4th Q: RR = 1.60; 95% CI: 1.07–2.42) and operations having equids participating in exercise-related activities (RR = 1.71; 95% CI: 1.16–2.50). Environmental risk factors associated with the incidence density of lameness included operations with stalls having medium flooring (RR = 0.48; 95% CI: 0.35–0.65), operations with stalls having loose flooring (RR = 2.78; 95% CI: 1.88–4.10) and operations using straw-like materials for stall bedding (RR = 2.02; 95% CI: 1.53–2.68).     

Bayesian estimates of genetic parameters for metritis, retained placenta, milk fever, and clinical mastitis in Holstein dairy cows via Gibbs sampling

The objective of this study was to estimate heritability and genetic correlations between the liabilities of clinical mastitis (CM), milk fever (MF), metritis (MET), and retained placenta (RP) within the first three lactations of Holstein dairy cows. The records of 57,301 dairy cows from 20 large dairy herds in Iran between January 2005 and June 2009 were analysed with univariate and bivariate threshold animal models, using Gibbs sampling methodology. The final model included the fixed class effects of herd-year, season of calving, parity of dam, the linear covariate effect of age at calving, and the random direct genetic effect of animal. Posterior means of heritability for liabilities in first, second, and third lactations were 0.06, 0.08, and 0.09, respectively, for CM; 0.10, 0.12, and 0.11, respectively, for MF; 0.09, 0.07, and 0.10, respectively, for MET, and 0.07, 0.08, and 0.08, respectively, for RP. Posterior means of genetic correlations between disease liabilities were low or moderate (from −0.01 to 0.26). The results of this study indicated the importance of health traits for considering in the selection index of Iranian Holstein dairy cows.     

Risk factors for Coxiella burnetii antibodies in bulk tank milk from Danish dairy herds

The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bulk tank milk (BTM) samples from 100 randomly selected Danish dairy cattle herds. Antibody levels were measured by an enzyme-linked immuno-sorbent assay. Before testing the herds, the farm managers were interviewed about hired labour, biosecurity, housing and herd health during the 12 months prior to the study. Variables considered important for C. burnetii antibody positivity in multivariable logistic regression analysis included the sharing of machines between farms (OR = 3.6), human contacts (OR = 4.2), artificial insemination by other people than artificial insemination technicians (OR = 7.7), routine herd health contract with the veterinarian (OR = 4.3) and hygiene precautions taken by veterinarians (OR = 5). In addition, herd size, hired labour, trading of cattle between farms, quarantine and use of calving and disease pens also showed significant association in univariable analysis. This study demonstrates that strict biosecurity is important for the prevention of infections with C. burnetii.     

Influence of modifiable risk factors on the incidence of stillbirth/perinatal mortality in dairy cattle

Bovine perinatal mortality is defined as the death of a full-term calf before, during or up to 48 h after calving. Recent studies indicate that the prevalence of bovine perinatal mortality is increasing, particularly in Holstein primiparae. Factors leading to a greater incidence of dystocia are the most important modifiable variables influencing the risk of perinatal mortality. Modifiable predictors are largely (age at first calving, breeding method, sire, calving management, feto-maternal health status and gestational nutrition) or moderately (calf breed, sex, gestation length) under the control of the dairy farm manager. Unlike non-modifiable risk factors, such as primiparity and fetal plurality, these factors can be manipulated to reduce the incidence of perinatal mortality.     

Methods and normal values for echocardiography in adult dairy cattle

ObjectiveThe objective of the study was to report normal ultrasonographic appearance and intra-cardiac dimensions in two dairy breeds and to calculate cardiac output (CO) using echocardiography.BackgroundIntra-cardiac dimensions, time indices and CO estimation have not previously been reported in adult cattle.Animals, materials and methodsEchocardiograms were obtained from healthy adult dairy cows (10 Jersey (J) and 12 Holstein Friesians (HF)) in the body weight range of 400 to 700 kg. Standard echocardiographic images were obtained from the left and right hemithoraces. Velocity time integrals were obtained in order to calculate CO using pulsed wave Doppler of aortic flow in the J cows. Measurements obtained included pulmonary artery and aortic diameters, left and right ventricular diameters (and calculated fractional shortening and left ventricular ejection fraction), left atrial size and time indices assessing valve function.ResultsHF cows had significantly (p < 0.05) larger pulmonary artery and aortic diameters, larger left atrial diameters and left ventricular internal diameters during diastole, but these were not different when corrected for body weight. Left and right ventricular dimensions, adjusted for body weight, were significantly larger (p = 0.02 and p = 0.035 respectively) in J cows when compared to HF cows. No differences were noted in the time indices between the two groups. No significant differences were noted in intra-operator variability and the only significant difference in inter-operator variability was in measurement of the pulmonary artery (p = 0.03; ICC = 0.63).ConclusionsIt is possible to obtain repeatable, reliable echocardiograms in order that meaningful intra-cardiac dimensions can be obtained in adult dairy cattle.