466 The effect of arginine supplementation during pregnancy on uterine blood flow in dairy heifers. C. Yunta*1, B. R. Mordhorst2, K. A. Vonnahme2, C. Parys3, and A. Bach1,4, 1Department of Ruminant Production-IRTA, Caldes de Montbui, Barcelona, Spain, 2Center for Nutrition and Pregnancy, Department of Animal Science, North Dakota State University, Fargo, 3Evonik Industries AG, Hanau, Germany, 4...

Docking the tails of dairy cattle causes mild to moderate behavior changes and physiological indicators of acute pain, but no studies have investigated the possibility that tail docking may lead to chronic pain. In human amputees, an incidence of increased limb surface temperature is associated with phantom limb pain, a central nervous system representation that survives peripheral loss. The ob...

Fecal culture for Escherichia coli O157:H7 was compared to rectoanal mucosal swab (RAMS) culture in dairy heifers over a 1-year period. RAMS enrichment culture was as sensitive as fecal culture using immunomagnetic separation (IMS) (P = 0.98, as determined by a chi-square test). RAMS culture is less costly than fecal IMS culture and can yield quantitative data.

This cross-sectional study evaluated risk factors associated with farm-level bovine leukemia virus (BLV) seropositivity in 563 dairy and 490 beef farms throughout Japan. Twenty randomly selected cattle on each farm were serologically tested, and farm epidemiologiocal information was obtained through face-to-face interviews. Due to the large number of zero-prevalence dairy and beef farms, data a...

The rearing period has a key influence on the later performance of cattle, affecting future fertility and longevity. Producers usually aim to breed replacement heifers by 15 months to calve at 24 months. An age at first calving (AFC) close to 2 years (23 to 25 months) is optimum for economic performance as it minimises the non-productive period and maintains a seasonal calving pattern. This is ...

Mastitis in dairy heifers in the peripartum period is a common and costly problem for producers, and mammary innate resistance is of key importance in defense of the gland from bacterial invasion. A prospective observational study was undertaken in 97 dairy heifers to measure associations between expression of eight innate resistance factors in mammary secretions collected from the same animals...