Dry whole plant of oat (grain plus straw) as a feed for growing bulls

Ignacio Ruiz N.1, Eduardo Barreau D.2, Gabriela Chahin A.1, Susana Muñoz M3 y Bernardo Arriagada C.1

This study is part of a lorage conservalion programa using lew or no machinery, simulating lhe siluation of a small larmer, localed in lhe Mediterranean dry land, lhal could be able lo sow oal, using animal traclion, during lall-winler; in summer lhe dry planl mighl be hand harvesled (wilh a sickle), and slocked lo be used as a leed lor periods of pasture shortage. In May, 1990, Nehuén oat (Avena sativa L.) was sown al La Platina Experimental Station (INIA). During January-February, lhe mature plants were harvested and stocked as sheal unlil April, when this malerlal was used as a leed in the lhree lollowing trealments: T1 = dry whole plant of oat (straw plus grain) as sole ralion, T2 = 85% dry whole plant of oat plus 15% of alfalfa hay and T3 = 75% dry whole plants of oal plus 25% of alfalfa hay. In each irealment 7 Herelord growing bulls of 264.3 kg of initial liveweight were used; these animals were fed the ralions during 83 days. In all irealments the dry malter intake was low as absolule value or fairly good when considering the kind of leed used: T1 = 1.73% of the Iiveweight (4.5 kg D.M./animal/day), T2 = 1.79% (4.71 kg) and T3 = 1.77% (4.69 kg). Estimation showed that energy consumed was enough to gel liveweight gain of around 0.4 - 0.6 kg/day; however the total protein was insufficient to reach gains of 0.2 kg/day, even in the best irealment. The change in liveweight did not show significant differences among irealments (P > 0.05), even when the trend was in favour of those rations with alfalfa hay. During the first 64 days some small liveweight gains where found in all treatments (0.23 kg/day in T1 and 0.37 kg/day in T3 ); though later, in all treatments the bulls lost weight aven when dry mattar intake did not decline in such period. Through this study il may be concluded that dry whole plant of oat seems to be adecuate only to maintain liveweight, when i

Keywords: oal, animal leeding, bulls, leeding value.
1 Estación Experimental La Platina (INIA), Casilla 439, Correo 3, Santiago, Chile.
2 Jackson 785, Viña del Mar, Chile.
3 Facultad de Ciencias Agrarias y Forestales. Universidad de Chile, Casilla 1004, Santiago, Chile.