Cow longevity in herds of different milk production levels and herd size. The effect of herd production level and herd size on cow longevity was studied using the SYMLEK system data on 12045 Polish Holstein-Friesian cows (Black-and-White variety) from 1371 herds. The cows, which belonged to the active population in Pomerania and Kujawy, first calved in 2008 and were used or disposed from the herds by the end of 2015. FREQ and GLM procedures from the SAS package were used in the statistical calculations. With increases in herd size (from ≤20 to >200 cows) and herd production level (from ≤6000 to 9000 kg milk), the culling level increased (p≤0.01) while the proportion of cows sold and alive decreased. Cow longevity was differentiated (p≤0.01) by herd size. As the number of cows in the herd increased, the lifespan and the length of productive life, as well as number of calvings decreased. The effect of herd production level on cow longevity was not statistically confirmed.
Epidemiological studies on caseous lymphadenitis were carried out in Poland in 1996 and 2002 among goat herds covered by a milk recording program. Between-herd seroprevalence was 13.2% in 1996 and increased to 62.5% in 2002. The average size of seropositive herds was statistically significantly higher than that of seronegative ones, however there was no statistically significant difference in the age between the herds. A statistically significant prevalence ratio (PR) was identified and relevant attributable risk for exposed animals (ARexp) was calculated for the following risk factors: presence of seropositive males in a herd (PR=8.350; ARexp=0.651), presence of superficial abscesses in animals (PR=6.142; ARexp=0.620), presence of respiratory signs (PR=2.900; ARexp=0.393), presence of animals in poor condition in a herd (PR=2.774; ARexp=0.390) and occurrence of reproductive failures in a herd (PR=1.798; ARexp=0.230). Purchase of animals from abroad, mastitis and husbandry conditions (housing system, grazing system, hygienic conditions) were not shown to be statistically significant risk factors.
The objective of this study was to estimate a herd-level seroprevalence of bovine herpesvirus type 1 (BHV-1) in herds with clinical symptoms of the respiratory tract. Eighty-three herds with suspected BHV-1 infection were selected and divided into two categories with respect to their size: small (n=27) and large herds (n=56). Samples were collected from calves, heifers and cows older than 24 months. Seroprevalence was determined using the gB ELISA test. The herd level seroprevalence was estimated as 53% (44/83) in the tested herds, 11.1% (3/27) in the small herds and 73.2% (41/56) in the large herds. Our study suggests that the current biosecurity measures still warrant improvement.
On dairy farms with high milk production there are much health problems. One of the most important periods, the critical time in dairy cows production is calving. In controlling and resolving of these problems the great role have the farmer and the veterinarian. There are many varied methods of dairy farms supervising. Diagnostic monitoring in herds of dairy cattle has an important role in controls an acceptable level of health and productivity in the cows and their progeny. Being familiar with the internal environment of the animal enables early detection of any dangers to the health of the animal and enables one to react before any clinical signs appear. Thus management in periparturient dairy cows is very important for prevention of many disturbances. The aim of the study was to compare the values of selected blood parameters in dairy cows shortly pre and post partum. It had to answer on the question The materials consisted of 30 clinical healthy cows tested 3-7 days before calving and 3-5 days after calving in this same good environmental and nutritional conditions (borning room). Selected twenty one various biochemical and morphological parameters of the blood similar to standard metabolic profile were included in the study. Significant differences (α=0.05) were noted in total bilirubin, SGOT, inorganic phosphorus, Calcium and Chloride. Parturition is an important period in cows from the point of view of the physiological changes taking place which in turn produce measurable, significant changes in the diagnostic parameters of the blood. These differences are presented in the paper.
The observational study was carried out in a population of Polish breeding goats in 2007 to determine the prevalence of fetal loss and identify risk factors contributing to its occurrence. The multivariate model allowing to predict the risk of the occurrence of fetal loss in a herd in a study population was developed. Data on the occurrence of fetal loss, as well as of 28 hypothesized risk factors were collected from goat owners using standardized questionnaire during face-to-face reviews on farms. Moreover, data on the herd-level seroprevalence of four abortifacient infections – Chlamydophila abortus, Leptospira spp., BVDV-1 and Neospora caninum – were included in the final analysis. Fetal loss was reported as occurring often in 12 of 49 goat herds (24.5%). The relationship between the hypothesized risk factors and the occurrence of fetal loss was verified in the multivariate logistic regression (α=0.05). Final analysis yielded four risk factors: regular veterinary supervision at least twice a year (OR 0.188; CI 95% 0.054 – 0.656), frequent occurrence of injuries and fractures (OR 3.172; CI 95% 1.081 – 9.310), frequent occurrence of respiratory signs in adult goats (OR 4.848; CI 95% 1.353 – 17.377) and presence of antibodies to C. abortus in a herd (OR 58.116; CI 95% 1.369 – 2466.438). The accuracy of the multivariate model was analyzed using receiver operating characteristic (ROC) curve technique. Area under the curve was 0.895 (CI 95% 0.801-0.981). For optimal cut-off value of 0.20-0.35 the multivariate model had sensitivity of 75.00% and specificity of 89.19% in predicting fetal loss in a herd.
An epidemiological study was carried out to determine the herd prevalence of Chlamydophila abortus and Coxiella burnetii antibodies in goats covered by a milk recording program in Poland. The survey took place in 2007 and 48 herds located in different parts of the country were involved. A representative sample from each herd was taken by a simple random sampling allowing to detect seropositivity of a herd on a 95% level of confidence. In total 918 goats were tested for specific antibodies against both germs with the use of enzyme-linked immunosorbent assays. In addition, history of reproductive failures was recorded in these herds. The survey revealed that the herd prevalence of C. abortus was 4.2% (2 herds) while no C. burnetii antibodies were found. Abortions were reported to be a problem in 80% of herds while repeating estrus was encountered in 46% of herds. Reproductive failure concerned two seropositive herds as well. Since the germ is present in the population, it has to be taken into consideration in diagnostic process. Nevertheless, the results of the present study indicate that C. abortus infection occurs infrequently in Polish goats. As no antibodies against C. burnetii were detected in the screened sample the risk of goat-to-human transmission of both bacteria in Poland seems to be very low.
Influence of cow temperament and milking speed on herd life, lifetime milk yield and reasons of cow culling.Importance of functional traits, longevity or reproduction traits increases continuously in present dairy cattle breeding. Effects of milking speed and cow temperament on herd life, lifetime milk yield and reasons of culling were estimated. The highest lifetime yield (p<0.01) of milk, fat and protein as well as life span and herd life had calm animals or slow milking cows. However, cows with normal temperament or fast milking had the highest (p<0.01) yield of milk fat and protein per one day of utilization. The main reason of culling were fertility and reproductive disorders (on average 41.2%), but 15.3% cows were culled because of udder diseases. Results suggest highly significant (p<0.01) influence of temperament and milking speed on life span, herd life, lifetime milk yield. Functional traits, longevity or fertility should be parts of breeding programs to balance dairy cattle selection and compensate negative influence of selection only towards milk yield that took place in the past.
The efficiency of tranfer of maternal immunity and its infuence on the kids' health was observed in a herd in which kids (n=20) had whole contact with the dam (n=13). The factors associated with dam, kid and human, which influence the efficiency of passive transfer were observed. It was estimated that the single-born kids reached higher serum y-globulin level (mean 23.14 g/dm3) than twin kids (mean 18.2 g/ dm3) (p < 0.05). The y-globulin level was the highest in single-born kids at 48 h, and in twin kids in 24 h of life. The IgG class antibodies to herd-homologous strains of Pasteurella multocida and Escherichia coli were estimated using ELISA in sera, colostrum and milk whey samples of dams and sera of kids. It was found that maternal antibodies specific to these two facultative pathogens decreased in kids sera rapidly and the self humoral immune response occurred within the period of observation. Two kids delivered by goats with lowest hierarchic position in the herd showed failure of passive transfer, and died at the 10th and 12th weeks of life due to chronic infections induced by both above mentioned bacterial strains.