The objective of this study was the serological, bacteriological and molecular diagnosis, as well as the molecular characterization of Mycobacterium avium subsp. paratuberculosis (Map) in adult cows of five Colombian dairy herds. Serum samples were tested by an indirect absorbed enzyme-linked immunosorbent assay (ELISA-C). All fecal samples were tested by pooled culture. After that, fecal sampl...

Health traits are of increasing importance to dairy producers. In the Scandinavian countries, direct selection for improved disease resistance has been carried out for more than 30 years (Philipsson and Lindhé, 2003). In these countries, veterinary treatments are recorded, as all treatments involving antibiotics and hormones have to be made primarily by a veterinarian. As veterinarians have ext...

Objective- Locomotor disorders are prevalent health problems in dairy herds that negatively affect milk production, reproduction performance and animal welfare. The ultimate cost of locomotor disorders in dairy cattle is substantially greater than treatment costs alone. As limited information is available on incidence of feet and leg disorders in Iran, the objective of this study was to determi...

Twinning in cattle is a complex trait that is associated with economic loss and health issues such as abortion, dystocia, and reduced calf survival. Twinning-rate QTL have been detected previously on BTA5 in the North American Holstein and Norwegian dairy cattle populations and in a USDA herd selected for high twinning rate. In previous work with the North American Holstein population, the stro...

this study was carried out to control johne’s disease (jd) without interfering with tuberculosis (tb)control programme. a dairy herd (n>1500 heads) was used over a period of 6 years, from 1994 to 1999 forthis investigation. the herd had a history of heavy infection with mycobacterium avium paratuberculosis(map) with culling rates of 1.5 and 5%, in 1991 and 1995, respectively. the mean annual lo...

Herd fertility is a key factor for the sustainability of cattle farming. However, since the 1980s, fertility in dairy cattle has steadily decreased and has become one of the main causes of culling and cow replacement in developed countries (Lucy, 2001; Barbat et al., 2010). Many studies have been performed in the last decades to investigate the genetic bases of this decline, considering the rep...

birth weight (bw) is the first trait recorded fllowing birth. it can influence the performance of thecow and as well impact the performance of the calf it,s duringits maturity. to investigate the effect ofa calf,s bw on the performance of holstein dairy cattle in iran, the records gathered between 1967 and2010 were obtained from the iranian animal breeding center. the data were then used to mod...

Epidemiological models enable to better understand the dynamics of infectious diseases and to assess ex-ante control strategies. For Mycobacterium avium subsp. paratuberculosis (Map), possible transmission routes have been described, but Map spread in a herd and the relative importance of the routes are currently insufficiently understood to prioritize control measures. We aim to predict early ...

There are many potential causes of abortion and fetal wastage in beef cattle; all can result in significant economic losses to the producer. Determination of the etiology is fundamental to developing recommendations regarding abortion control and prevention. Since it was first described as a cause of bovine abortion in New Mexico in 1987 (1), infection with Neospora sp. has emerged as a signifi...

OBJECTIVE To compare the frequency of isolation, genotypes, and in vivo production of major lethal toxins of Clostridium perfringens in adult dairy cows affected with hemorrhagic bowel syndrome (HBS) versus left-displaced abomasum (LDA). DESIGN Case-control study. ANIMALS 10 adult dairy cattle with HBS (cases) and 10 adult dairy cattle with LDA matched with cases by herd of origin (controls...