Weekly, Oklahoma State University Extension Beef Cattle Nutrition Specialist Paul Beck offers his expertise on the beef cattle industry. This is a part of the weekly series known as the “Cow-Calf Corner.” Today, he talks about predicting the performance of finishing steers.
When we are considering keeping some calves through finishing, it would be great if we had an idea about which ones we should keep, and which ones should be marketed to let someone else take the risk of feeding them. Commercial labs have developed genomic testing to determine the genetic merit of livestock by a simple tissue or blood test. The use of genomic testing of feeder cattle prior to feedlot entry may allow for feedlot managers to make enhanced management and marketing decisions or can allow producers to make informed decisions regarding retained ownership of a portion of their calves through finishing.
We conducted research at OSU to determine the predictive value of these tests on postweaning performance and efficiency. This research project utilized the Igenity Beef Index (Neogen, Lansing, MI) to determine its predictive value for performance of beef steers post-weaning. The Igenity Beef Index provides a score on a scale of 1-10 for 17 maternal, performance, and carcass traits. The objective of this study was to determine differences in performance and efficiency of finishing steers utilizing Neogen Igenity Beef scores for average daily gain (ADG). Spring born commercial Angus steer calves from the OSU Range Cow Research Center [n = 83; body weight (BW) = 924 ± 70.3 lb] were placed on feed at the Willard Sparks Beef Research Center on May 5, 2022, after grazing wheat pasture for 155 d. The steers were allocated by scores for genetic growth potential into Low Growth (ADG scores 1 – 4), Medium Growth (ADG scores = 5 – 6), or High Growth (scores = 7 – 10) gain feeding groups based on Igenity Beef ADG Score.
There were no differences in daily gains during preconditioning or while grazing wheat, so there was no difference in initial finishing bodyweight due to Igenity ADG scores. There were no differences in intake or gain during the step-up period between entry into the feedyard and starting of the final finishing diet. Steers with High Growth scores gained weight more rapidly during finishing and weighed more at harvest than steers with Medium Growth and Low Growth steers. Growth score was shown to influence feed intake during finishing with High Growth steers consuming more feed than Medium Growth or Low Growth steers. But High Growth steers were more efficient in utilizing feed due to their greater performance. Steers with High Growth scores had greater hot carcass weights than Medium Growth and Low Growth steers. These data indicate that Igenity ADG scores can be used to select cattle with improved performance, feed efficiency, bodyweight at harvest, and hot carcass weight without impacting carcass quality grade.
