Comparison of the Effects of Hay and Corn Silage Growing Diets of Performance and Economic Returns of Different Steer Types2

Publisher Website
Google Scholar
Abstract
Effects of different growing diets and breed type on feedlot performance and carcass traits of 209 crossbred steer calves were evaluated in each of 2 years. Steers were sired by Angus or Charolais bulls. Dams were of four different breed types. Calves were placed in drylot immediately after weaning at an average age of 7 months and were evaluated during growing (G), finishing (F) and total (T) feedlot periods. Steers fed corn silage for a 16-week G phase gained faster (P<.01), consumed less (P<.05) dry matter (DM) per unit gain and had higher (P<.05) returns above feed costs than did calves fed alfalfa-orchardgrass hay during G. Daily gain during F (13 to 21 weeks) was not influenced (P<.05) by G diet. Breed of sire and dam did not affect (P>.05) daily gain during G, nor did sire breed influence DM per unit gain during G. Charolais-sired steers gained more rapidly (P <.01) than did Angus-sired calves during both the F and T periods. Breed of dam influenced (P <.01) both initial and carcass weights of steers and affected (P <.01) F and T daily gains. Sire breed influenced (P <.01) all carcass traits except price. Carcass weight was not affectd (P>.10) by growing diet in year 2, but in year 1, carcasses of steers grown on hay were heavier (P<.05). Adjusted to constant weight, carcasses of corn silage-grown steers in year 1 had greater (P<.05) fat depth, higher percentage kidney-pelvic-heart (KPH) fat, lower marbling score and lower quality grade than did carcasses of steers fed hay during G. Breed of dam influenced (P<.05) fat depth over the ribeye, marbling score, quality grade and yield grade. Growing steer calves on corn silage diets in each of 2 years resulted in more rapid total feedlot gain, less DM per unit gain, fewer days on feed and greater total returns above feed costs per steer than did growing steer calves on hay. There was no indication (P >.05) of a diet x sire breed interaction on feedlot daily gain or carcass traits. Copyright © 1980. American Society of Animal Science . Copyright 1980 by American Society of Animal Science