FISH PROTEIN CONCENTRATE (CONMAR 80) OR REFINED SOY FLOUR AS SUBSTITUTES FOR SKIM MILK POWDER IN CALF MILK REPLACERS

Abstract

A new commercial hexane-extracted fish meal, Conmar 80, (80% CP) and soy flour were used as protein sources in milk replacer diets for young dairy calves. Three milk replacers, identical in composition except for the diet protein source, were offered in two experiments to Holstein Friesian male calves. The three treatments were: 50% skim milk (SM), 27% whey (W); 22% SM, 47% W, 9% Conmar 80; and 22% SM, 42% W, 15% soy flour. The first experiment compared calf performance parameters and a second experiment compared digestibility parameters for the three diets. A total of 132 Holstein calves were involved in trial 1 and 12 Holstein calves in trial 2. Calf performance, feed efficiency and mortality were not different from controls when Conmar 80 was included as a protein source (36%) in milk replacer. Partial replacement of skim milk powder with soy flour as 37% of the protein source gave lower average daily gains, a higher feed conversion and mortality rate. The digestibility data for all rations were similar. The results indicated that approximately one-third of the protein in milk replacer could be provided by fish protein concentrate in place of skim milk powder without any reduction in calf performance. Key words: Dairy calves, milk replacer, performance, Conmar 80