Holstein steers (n = 2,275) were assigned to 1 of 3 treatments: 1) a control diet containing no β-agonists, 2) a diet that contained zilpaterol hydrochloride (ZH; 8.3 mg/kg [100% DM basis]) for 20 d with a 3-d withdrawal period before harvest, and 3) a diet that contained ractopamine hydrochloride (RH; 30.1 mg/kg [100% DM basis]) for 28 d before harvest. No differences (P ≥ 0.18) were detected ...

Retail cutting tests were conducted on subprimals from cattle fed zilpaterol hydrochloride (ZH) to determine if the improved carcass composition and red meat yield resulting from ZH feeding would translate into increased retail yields of ready-to-cook products. As part of a 3-phase study, selection of carcasses from Holstein steers was done once (fall 2008), followed by the collection of carcas...

The objective of this study was to investigate the genetic relationship between body condition score (BCS) and reproduction traits for first-parity Canadian Ayrshire and Holstein cows. Body condition scores were collected by field staff several times over the lactation in herds from Québec, and reproduction records (including both fertility and calving traits) were extracted from the official d...

The objectives of the present study were to describe pathomorphological and immunohistochemical features of congenital cerebellar hypoplasia associated with natural BVD-MD virus infection in a Holstein-Friesian calf. The characteristic macroscopical lesion was cerebellar hypoplasia, almost completely absent, with hydrocephaly. Cerebellar changes were cortical destruction, destructive changes of...

Spinal dysraphism, not associated with vertebral defect or arthrogryposis, was found in a 3-day-old Holstein-Friesian calf that was clinically diagnosed as having encephalopathy. The dysraphic lesion occurred in the sixth (C6) and seventh (C7) segments of the cervical spinal cord. Microscopically, the lesion was characterized by hydromyelia, syringomyelia, anomaly of the ventral median fissure,...

Beef production is a recognized source of greenhouse gas (GHG) and ammonia (NH(3)) emissions; however, little information exists on the net emissions from beef production systems. A partial life cycle assessment (LCA) was conducted using the Integrated Farm System Model (IFSM) to estimate GHG and NH(3) emissions from representative beef production systems in California. The IFSM is a process-le...