نتایج جستجو برای: sorted semen dairy herds
تعداد نتایج: 73289 فیلتر نتایج به سال:
BACKGROUND Bovine respiratory disease (BRD) is 1 of the 2 most important causes of morbidity and mortality in dairy calves. Surprisingly, field data are scant concerning the prevalence of respiratory pathogens involved in BRD in preweaned dairy calves, especially in small herds. OBJECTIVES To identify the main respiratory pathogens isolated from calves in Québec dairy herds with a high incide...
A bulk milk quality assurance programme for Mycobacterium avium subsp. paratuberculosis (Map) in dairy herds was simulated with a stochastic simulation model (JohneSSim). The aim of this study was to evaluate the epidemiological and economic effects of preventive management measures and various test schemes in a simulated population of closed Dutch dairy herds over a 20-year period. Herds were ...
The objective was to determine whether transfer of fresh or vitrified embryos produced in vitro with sex-sorted semen improves pregnancy and calving rates during summer in lactating dairy cows compared with artificial insemination (AI). Lactating dairy cows (n=722) were enrolled during summer months at 2 commercial dairies in Central Texas and randomly assigned to 1 of 3 treatments: AI with con...
BACKGROUND Mastitis is one of the major threats to animal health, in organic farming as well as conventional. Preliminary studies of organic dairy herds have indicated better udder health in such herds, as compared to conventional herds. The aim of this paper was to further study mastitis and management related factors in certified organic dairy herds. METHODS An observational study of 26 cer...
BACKGROUND Mycoplasma bovis is an important pathogen causing severe disease outbreaks in cattle farms. Since 2011, there has been an apparent increase in M. bovis outbreaks among Danish dairy cattle herds. The dairy cattle industry performed cross-sectional antibody screening for M. bovis on four occasions, using the indirect BIO K 302 M. bovis enzyme-linked immunosorbent assay (ELISA) (Bio-X, ...
to describe proportion and pattern of culling in commercial dairy herds of khorasan razavi province, this survey was carried out from 21st march 2008 to 20th march 2009 in 15 industrialized dairy herds. for each culled cow data related to parity at culling, last calving to culling interval and primary reason for culling were recorded. annual herd exit rate was 20.9%. out of a total of 652 culle...
Use of sexed semen for artificial insemination of US Holstein heifers (1.3 million breedings) and cows (10.8 million breedings) in Dairy Herd Improvement herds was characterized by breeding year, parity, service number, region, herd size, and herd milk yield. Sexed semen was used for 1.4, 9.5, and 17.8% of all reported breedings for 2006, 2007, and 2008, respectively, for heifers, and for 0.1, ...
The purpose of the research was to assess changes in lactation activity cows and their impact on level reproduction, as well study fluctuations with respect genetic environmental factors. A sample 807 various ages formed for study. were kept a commercial farm Kharkiv region, Ukraine. Data from DairyPlan C21 software used It revealed that parameters Wood curve model significantly influenced by c...
BACKGROUND Infection with Coxiella burnetii, the cause of Q-fever, has never been detected in Norwegian animals. Recognising the increasing prevalence of the infection in neighbouring countries, the aim of the study was to perform a survey of Norwegian farmed ruminants for the prevalence of C. burnetii infection. RESULTS Milk and blood samples from more than 3450 Norwegian dairy cattle herds,...
26 herds with 71 586 individual records were used. We tested a hypothesis that milk efficiency was influenced by the elevation of the farm, housing system, breed, area of altitude, and by the cooling of dairy cows. There were 20 herds from lowlands and 6 herds from mountains, 20 herds from free-stall housing, 6 herds from tie-stall housing. 8 herds consisted of Slovakian Pied cattle, 4 herds of...
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