Because of the importance of bred heifers to the future milk production of any dairy operation, it is critical that udder health be maximized to ensure that animals freshen free of intramammary infection (IMI). During the heifer’s first gestation, the presence of mastitis can compromise the development of milk-producing tissues, and in the case of Staphylococcus aureus, milk yield may be reduce...

Mammary secretions of 913 quarters from 229 pregnant Holstein heifers were obtained aseptically to determine the prevalence of coagulase-negative Staphylococci isolated during periparturient period. Quarter samples were collected 14 to 10 days before expected parturition. Analysis of culture data indicated that 78.5% (717/913) of samples were negative, 20.5% (187/913) contained coagulase-negati...

This study examines a national survey of professional custom heifer growers. Sixty-five respondents from 23 states provided information on operation size and characteristics, management practices, and contract terms. Responding operation current heifer inventories ranged from 30 to 20,000 heifers and the average operation had more than 1200 heifers on-farm. The regional pattern of operation siz...

The aim of this thesis was to explore conditions for selection and genetic improvement of fertility and longevity in dairy cattle. The background is that single-trait selection for milk production is known to lead to impaired fertility and consequently to shorter lifespan. This in turn results in financial losses and ethical concerns. Since many years, the Swedish dairy farmers have recorded mi...

Ayhan BAŞTAN*, Seçkin SALAR, Mehmet CENGİZ, İsfendiyar DARBAZ, Mürşide Ayşe DEMİREL, Doğukan ÖZEN Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Near East ...

The overall object of this research was to characterize US Holstein (virgin) heifer fertility. This included investigation of factors influencing heifer fertility and estimation of heritability, as well as correlations with cow fertility and first-lactation milk yield. A secondary objective was to compare linear and logistic model estimates of fixed effects and linear and threshold model estima...

Salmonella enterica subsp. enterica serovar Typhimurium var. Copenhagen isolates from a heifer-raising operation and from 11 dairy herds that had their calves contracted to the heifer-raising operation were examined for their phenotypic and genotypic characteristics. Results of the study showed that the heifer-raising operation could serve as a clearinghouse for Salmonella serovar Typhimurium v...

the present study aimed to estimate the effects of parity, calving season and year of calving on the prevalence of subclinical mastitis in holstein cows. a total of 2682 records from 869 holstein cows in a large dairy farm (azarbaijan province, iran), respecting the period from 2006 to 2009, were collected. data was analyzed using proc mixed of sas software by mivque method. subclinical mastiti...