Effect of route of administration of lasalocid on response of young dairy calves

Abstract

Forty newborn bull calves were assigned to one of four feeding groups. The feeds either contained lasalocid in milk (M), prestarter (PS), and starter (S); lasalocid in PS and S; lasalocid in S only; or no lasalocid. Calves were fed M at 8% of birth weight (bw) daily and offered PS to a maximum of 0.5 lb daily. When 0.5 lb of PS was consumed in one day the calves were fed M at 4% of bw daily. They were weaned when they consumed dry feed at the rate of 1.3% of bw. Daily feed intake and weekly weight gains of calves were evaluated. Blood serum samples were used to evaluate blood metabolites at wk 4, 8, and 12. We concluded that lasalocid in M, PS, and S supported greater feed efficiency and allowed earlier weaning with less animal variation than when lasalocid was delivered in PS and S, only in S, or not at all.