The utilization by pigs of methionine from five protein concentrates compared with synthetic methionine.

Pigs (n 100) between 28 and 56 d of age were given diets containing one of five protein concentrates ad lib. The utilization of methionine from the protein concentrates was compared with synthetic methionine. Increasing the methionine content of the diets from 1.5 to 2.2 g/kg diet increased the weight gains of the pigs from 61 g/d to 198-292 g/d. The feed conversion efficiencies decreased from 2.56 to 1.34-1.56. The utilization of methionine from the protein concentrates for weight gain, as compared with synthetic methionine, was meat meal A 0.89, meat meal B 0.97, soya-bean meal 1.02, cotton-seed meal 0.87 and dried skim milk 1.04.