Influence of Betaine on Pasture,Finishing, and Carcass Performance in Steers

Two experiments were conducted to investigate the effects of supplemental betaine on steer performance, fat deposition, and carcass characteristics. In Exp. 1 (grazing phase), 80 steers (317 kg) were fed either 1.0 kg of a control supplement (30% CP) or 1.0 kg of the control supplement plus 20 g of betaine per head per day. Betaine supplementation had no effect on overall gain or fat deposition (P>0.10) but increased ADG (P<0.10) during d 46 to 90 (0.64 vs 0.72 kg; control vs betaine, respectively). The pasture groups remained intact and were moved to the feedlot for 141 d and fed a control diet or the control diet plus 20 g of betaine per head per day. Betaine had no overall effect on finishing gain (P>0.10); however, this response was variable by period. Betaine increased final fat thickness and fat thickness change (P<0.10), but did not affect marbling or longissimus area (P>0.10). Supplemental betaine on pasture increased feed intake, final BW, and hot carcass weight (P<0.05) and increased final fat thickness and fat thickness change (P<0.10) during the finishing phase. In Exp. 2, supplemental betaine (40 g/d) was fed to steers (averaging 584 kg) in 11 replications during the last week before harvest. The overall weighted average increase in dressing percentage when betaine was fed was +0.34% (P<0.05). There was no effect (P>0.10) on fat thickness or marbling. Season of year did not affect response.