Ernesto Jahn B.1, Germán Klee G.2, Ignacio Ruiz N.1 y Hugo Vyhmeister B.2
Two experiments to study the levels at which sugar beet tops and leaves can be included in actating cow rations, were conducted at the substation Human (Los Angeles) of INIA (Chile). ln the first experiment the treatments were: 1) Sugar beet tops and leaves (SBT) + 9 Kg. dried sugar beet pulp (BP); 2) SBT + 9 Kg. BP + 1.5 Kg. rape seed meal (RSM); 3) SBT + 3 Kg. BP + 0.8 Kg. fish meal, and 4) SBT + 3 Kg. BP + 1.5 RSM + 0.8 Kg. fish meal. In both trials, 5 Kg. red dover hay and a bone meal-salt mixture were offered to al cows. SBT and red dover silage (RCS) (Exp. 2) were offered ad ilbitum. Milk production with treatment 1 (11.4 Kg. of 4°/o FCM) was lower (P< 0.05) than with al other treatments, where production averaged from 13.4 to 13.9 Kg/day.
When high leves of BP are used, protein has to be supplemented. SBT can supply up to 40% of total dry matter intake, without affecting production. ln the second tria! the treatments were: 1) SBT; 2) SBT + concentrate (C); 3) Red dover silage (RCS), and 4) RCS + C. The concentrate, with 16% protein and 67% TDN, was offered at a rate of 1 Kg. per each 3 Kg. of milk produced aboye a minimun of 8 Kg. Milk production (9.1 - 12 Kg. FCM/day), and fat test were not significantly (P > 0.05) different between treatments. Live weight gains were lower (P< 0.05) on treatment 3. Interaction of concentra te leve ‘and forage type was significant (P < 0.05) for forage dry matter intake. SBT intake decresed (P <005) from to 5.7 Kg/cow/day as concentra te was fed, but RCS intake was not affected by C feeding. total dry matter intake for cows on RCS without C was lower than with C (P <0.05).
1 Ing. Agr., Ph.D., Estación Experimental Quilamapu, Instituto de Investigaciones Agropecuarias (INIA), Casilla 426, Chillán, Chile.
2 Ing. Agr., Estación Experimental Quilamapu, Instituto de Investigaciones Agropecuarias (INIA), Casilla 426, Chillán, Chile.