Effect of transport stress on respiratory disease, serum antioxidant status, and serum concentrations of lipid peroxidation biomarkers in beef cattle.

Objective: To determine the effect of transportation stress on serum concentrations of oxidative stress biomarkers of calves.

Animals: 105 crossbred beef steer calves (mean [+/-SD] body weight, 207 +/- 21.2 kg).

The bovine 5' AMPK gene family: mapping and single nucleotide polymorphism detection.

The 5'-AMP-activated protein kinase (AMPK) family is an ancient stress response system whose primary function is regulation of cellular ATP. Activation of AMPK, which is instigated by environmental and nutritional stresses, initiates energy-conserving measures that protect the cell by inhibition and phosphorylation of key enzymes in energy-consuming biochemical pathways. The seven genes that comprise the bovine AMPK family were mapped in cattle by using a radiation hybrid panel.

Bovine viral diarrhea virus (BVDV) 1b: predominant BVDV subtype in calves with respiratory disease.

The prevalence of bovine viral diarrhea virus (BVDV) infections was determined in 2 groups of stocker calves with acute respiratory disease. Both studies used calves assembled after purchase from auction markets by an order buyer and transported to feedyards, where they were held for approximately 30 d. In 1 study, the calves were mixed with fresh ranch calves from a single ranch.

Bovine adenovirus serotype 7 infections in postweaning calves.

Objective: To detect bovine adenovirus serotype 7 (BAV-7) infections in calves by use of viral isolation and serologic testing.

Animals: 205 postweaning calves.

Procedure: 121 calves were assembled by an order buyer through auction markets in eastern Tennessee and transported to New Mexico where they were commingled with 84 healthy ranch-reared calves.

Effects of vaccination prior to transit and administration of florfenicol at time of arrival in a feedlot on the health of transported calves and detection of Mannheimia haemolytica in nasal secretions.

Objective: To determine effects of vaccination prior to transit and prophylactic administration of florfenicol at time of arrival at a feedyard on health of cattle and colonization of the nasopharynx by Mannheimia haemolytica (MH).

Animals: 121 steers from Tennessee and 84 steers from New Mexico.

Procedure: Half of the steers were vaccinated before transport to a feedyard.