Data on the performance of individual beef cattle from birth to processing can be used to improve herd management and genetic characteristics such as fertility, weaning weight and tenderness. Likewise, tracing the origins and whereabouts of cattle that may have been exposed to infectious disease agents is necessary to protect the health of the national beef herd. Such information is rarely available, in part because cattle often change ownership during the beef production process. A system developed to support the lifetime tracking of individual cattle in the UC Davis beef herd seamlessly transfers information between the UC Sierra Foothill Research and Extension Center, UC Davis campus feedlot and a commercial beef-cattle processing plant, and provides a repository for performance data collected at all production stages. The system provides real-time data sharing, as well as integrated analysis and management evaluation options, and will be a valuable resource for beef-cattle research. UC livestock farm advisors are now implementing a similar system with cooperating commercial ranches.

Sixty percent of cattle not dewormed within 4 months of sampling were shedding parasite eggs or larva. The prevalence of shedding varied greatly for different types of internal parasites. Prevalence of shedding for major Strongylate nematodes was 54%; thread-necked intestinal nematodes, 6%; lungworms, 0.8%; coccidia, 18.1%; and tapeworms, 2.1%. Anthelmintic (deworming) treatments lowered prevalence compared to untreated cattle, but the major Strongylate nematodes and coccidia were still sufficiently prevalent that the resulting pasture contamination would restrict the potential success of control programs.

Selenium (Se) deficiency occurs commonly in California grazing cattle and has been associated with reduced immune function and, in some studies, reduced weight gain. Multiple methods of supplementing Se are available, but little research has compared the effects of these methods on whole blood Se levels and weight gain. In two trials, we evaluated four methods of Se supplementation — an intrarumenal bolus, two injectable preparations and a loose salt containing 120 ppm Se — over an 85- to 90-day period in Se-deficient yearling cattle in Tehama County. The bolus treatment raised whole blood Se levels to an adequate level (0.08 ppm) for the entire study period. Whole blood Se concentrations in injected cattle initially reached adequate levels but then declined to deficient levels. The loose salt treatment acted slowly, with average whole blood Se concentration reaching adequate levels at the end of the study period. None of the treatments significantly affected weight gain and Se blood concentration was not correlated with weight gain. In growing cattle, it appears that Se supplementation may be viewed not as a direct driver of weight gain, but rather as similar to vaccination, in that it can prevent health problems that might otherwise lead to reduced weight gain.