RESIDUAL FEED INTAKE AND THE RELATIONSHIP WITH PERFORMANCE, TEMPERAMENT AND CARCASS TRAITS IN GROWING AND FINISHING STEERS

<p>Two trials were conducted with Santa Gertrudis steers, trial 1 (n = 115) and trial 2 (n = 118), were fed a roughage-based diet during the growing phase and high-grain diet during the finishing phase. Steers were weighed at 14-d intervals and dry matter intake (DMI) measured for 70 d during both phases. Residual feed intake (RFI) is the difference between actual DMI and DMI predicted from linear regression of DMI on mid-test metabolic body weight. Ultrasound carcass measurements were measured on day 0 and 70 of the growing phase. Steers were harvested after finishing phase and carcass cooler traits were obtained. Low RFI steers consumed less than high RFI steers, but did not differ in average daily gain (ADG). Low RFI steers had less backfat compared to high RFI steers. Residual feed intake was independent of growth rate and mature body size, but highly correlated with DMI. Moreover, adjusting RFI for ultrasound carcass traits could improve feed efficiency independent of growth, body size, and carcass composition. Furthermore, residual gain (RG) could have an effect on marbling and quality grade.</p>

Name thesis:degree_name

Master of Science - Agriculture

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Agriculture

Year dc:date.available

2016

Author dc:creator

• Branton, Courtney R.

Contributors dc:contributor

• Erin. G. Brown
• Gordon E. Carstens
• John Michael P. Mehaffey

• Beef Cattle
• Residual Feed Intake
• Carcass
• Temperament
• Animal Studies

Repository record dc:identifier

https://scholarworks.sfasu.edu/etds/51

OAI identifier oai:identifier

oai:scholarworks.sfasu.edu:etds-1060