ABSTRACT: This study aimed to establish the prevalence of animals persistently infected (PI) with bovine viral diarrhea virus (BVDV) in dairy farms at Parana State, Brazil. Samples were collected from 6,465 female Holstein Friesian Dairy Cattle, including less than two years old, females over old who had not given birth farm, and mothers calves diagnosed as infected. The cattle came 40 herds di...

Death of calves around parturition is a matter of concern for dairy farmers. Relatively high stillbirth rates and unfavourable trends have been reported for Holstein heifers in the Netherlands and several other countries. In our study, we investigated herd differences, genetic parameters and genotype by environment interaction for heifer calf livability. A large dataset with data from calvings ...

Problem statement: Imported Holstein Friesian dairy cattle are exposed to hot arid climate in feedlot management in Kuwait. Desert climate is extreme reaching high 45-50°C in summer and low -4oC in winter at day and night respectively. High calf mortality, poor reproduction and milk yields were main constraints to viable dairying. The objectives of this study were to assess the magnitude of cal...

seven hundred and sixty-eight blood samples of pregnant cattle from four holstein dairy herds that are farmed in the vicinity of tehran were used to evaluate the seroprevalence of neospora caninum infection by enzyme-linked immunosorbent assay (elisa). two hundred and ninety-eight of the 768 blood samples (38.8%) were positive for this infection. the prevalence of infection in the herds varied ...

The aim of this study was to determine the prevalence of clinical mastitis and somatic cell count (SCC) in six dairy herds which had different milking management and hygiene conditions. Four hundred thirty one Holstein Friesian cows were used in the study. The herds were classified to be good (Group 1, n=2), medium (Group 2, n=1) or bad (Group 3, n=3) according to milking management and hygiene...

subacute ruminal acidosis (sara) represents one of the most important metabolic subclinical disordersof high producing dairy cows, having serious impact in both animal health and herd profitability. the aim ofthis study was to confirm the presence of sara in greek dairy herds and record its prevalence and riskfactors. ruminal fluid samples, via rumenocentesis, were obtained from a total of 153 ...

the purpose of this study was to investigate the effect of maternal inbreeding on incidence of twinning,dystocia and stillbirth in holstein cows of iran. calving records from march 2000 to april 2009 comprisingof 365,021 calvings on 153,802 cows from 86 dairy herds were used. the mean level of inbreeding was0.7%, less than 37% of all animals were inbred, and a small proportion (3.45%) of inbree...

Problem statement: A high mortality rate (crude mortality 43.6%) of pre-weaned dairy calves resulted in unavailability of replacement heifers in Kuwait. Dairy producers resorted to import pregnant heifers for herd replacement. This study was undertaken to investigate the effects of dam vaccination and age, serum Immunoglobulin (Ig) on disease syndromes and mortality in preweaned calves. Approac...

Reproductive performance is a key driver of the economics of dairy and beef breeding herds. In the absence of hormonal treatment to induce or stimulate lactation, regular parturition and initiation of lactation are key events directly affecting the average daily milk production of dairy herds, culling decisions and farm gross margins. Thus efficient reproductive management is a critical prerequ...