Andrea K. Watson
Galen E. Erickson
Date of this Version
Melton, B. A. 2018. Impact of shade on performance and heat stress of finishing cattle and pooled analysis of individually fed finishing trials. Thesis.
IMPACT OF SHADE ON PERFORMANCE AND HEAT STRESS OF FINISHING CATTLE AND POOLED ANALYSIS OF INDIVIDUALLY FED FINISHING TRIALS
A commercial feedyard trial in Eastern Nebraska evaluated the effect of shade vs no shade on cattle performance, ear temperature, and panting scores. No differences in overall performance (final BW, DMI, ADG, and G:F) or carcass characteristics (HCW, 12th rib fat thickness, marbling, LM area, and calculated YG) were observed. Cattle that were provided shade had lower panting scores and ear temperatures, and greater DMI, compared to cattle that had no shade during heat events. Also, a treatment by hour interaction for movement of cattle occurred for one of the heat events. In comparison, the cool event had greater DMI and lower panting scores for the cattle that were provided shade compared to the cattle without shade, but ear temperature and movement were not different. Providing shade to cattle in southeast Nebraska reduced measures of heat stress for feedyard cattle.
A pooled-analysis of individually fed cattle was conducted to determine the relationships of metabolizable energy (ME), DMI, ADG, G:F, and carcass traits. Increased amounts of ME increased G:F. Animal ADG had a strong correlation (R2 = 0.72) with G:F, while the correlation between DMI and G:F (R2 = 0.02) was not as strong. Animal G:F was poorly correlated with 12th rib fat thickness (R2 = 0.01) and marbling (R2 = 0.01).
Advisors: Andrea K. Watson and Galen E. Erickson