EFFECT OF A SINGLE AND A DOUBLE HORMONE IMPLANT ON THE PERFORMANCE AND CARCASS CHARACTERISTICS OF HOLSTEIN-FRIESIAN STEERS FINISHED ON A TOTAL OR RESTRICTED CONCENTRATE FINISHING RATION

Implanting Holstein-Friesian steers twice with hormones during the finishing phase did not improve growth performance beyond that obtained from a single implant. Steers implanted twice and finished on a 40% concentrate and 60% hay ration grew as rapidly as steers finished on 100% concentrate; they had significantly less grams of fat (P < 0.05), but not grams of bone or lean, in their carcass rib sections. However, when the rib data were expressed on a proportional basis the animals in the roughage-fed group had significantly less lean and more bone (P < 0.05) as well as a lower percentage of fat in their rib sections than concentrate-fed animals.