ABSTRACT.
Barley levels in rations for fattening Hereford steers

Claudio Rojas G.1 y Rodrigo Contreras D.1
 

Thirty spring born Hereford steers 9-10 months old and 211 kg of liveweight, were fed with five different rations of barley grain, red clover hay, rapeseed meal and rapeseed soap stock, at the Carillanca Exp. Sta. (INIA-Temuco).
Barley grain was included at 0% (I),15% (II), 30% (III), 45% (IV) and 60% (VI), on a D.M. basis. Red clover hay, rapeseed meal and rapeseed soapstock were used in different proportions to complete each ration. Besides, minerals were offered at 2%. The tations were isoproteic and isoenergetic. A randomized design was used, with covariance analisis according to inicial weight of steers.
Dayly gains were 0.77b, 1.01 a, 1.07a, 1.11a and 1.07 a kg (P < 0.05) for the five rations respectively. D.M. intakes were 6.7b, 7.5a, 7.2a, 7.4a and 6.3b kg/day; the efficiencies of feed conversion were 8.8d, 7.4c, 6.8bc, 6.6bc and 5.9a kg D.M./kg L.W.; fat layer were 3.7b, 4.1ab, 4.9ab, 6.4a and 5.4ab mm and sirloin area were 45. 7b, 52.1 a, 53.1 a, 53.2a and 51.9ab cm2 (P < 0.05), for the same rations, respectively.

Keywords: barn, barley, hay, soap stock, rapeseed meal, carcass, Hereford steers.
1 Estación Experimental Carillanca, Casilla 58-D, Temuco, Chile.