PSII-A-3 Effect of Beef Breed Type Relative to Feedlot Performance, Feeding Behavior, and Carcass Characteristics

Abstract

Cattle production in the U.S. is being impacted by the changing global climate and limited availability of natural resources. Improving the efficiency of cattle production is imperative to make the most of these limited resources. Increasing the percentage of Bos indicus (BI) genetics within cattle herds is one potential method to address these issues, as they are able to withstand higher temperatures, are better adapted to nutritional stress, and consume less water than Bos taurus (BT) influenced cattle. The objective of this study was to examine steers of different breed types relative to feedlot performance, feeding behavior, and carcass characteristics. This study utilized a total of 115 steers of two different breeds: Angus (AN; n=83; 100% BT) and Santa Gertrudis influenced (SG; n=32; 19% BI, 81% BT). Steers were stratified by weight and randomly divided into one of four covered pens. Each pen was equipped with two GrowSafe bunks and all steers were fed the same typical ration. All steers were harvested at a commercial facility once industry average backfat standards were met. Individual dry matter intake and feeding behaviors were collected through the GrowSafe system. Weight, ribeye fat thickness, marbling score, and USDA yield grades were also assessed. Breed did not have an effect (P >0.10) on dry matter intake, average daily gain, ribeye fat thickness, hot carcass weight, or USDA yield grade. There was a tendency (P=0.09) for SG steers to spend more time with their heads down during individual GrowSafe bunk visits. Intramuscular fat was increased (P=0.0019) in AN steers compared to SG steers. Further research focused on genomic differences between cattle of different breed types is warranted to better understand the relationship between breed type and production performance characteristics.