Functional Fish Protein Concentrate in Milk Replacers for Calves

Abstract

A fish protein concentrate with improved function properties (i.e. water-holding and emulsification capacity) has been tested in milk replacers for calves as the principal source of protein in a semisynthetic diet and with dried whey in a practical diet. The fish protein concentrate did not cause digestive problems, and the calves remained entirely healthy when fed the fish protein concentrate as the principal source of protein from 3 to 63 days or together with dried whey from 2 to 12 wk of age. Apparent protein digestibility in calves between 7 and 63 days of age was curvilinearly related to age and was 90.5 and 96.1% for fish and milk protein. Practical milk replacers with the fish protein concentrate and dried whey had similar nutrient and energy digestibility but gave slightly lower nitrogen retention and growth rate compared with an all-milk milk replacer when fed as the sole feed to preruminant calves. When fed together with concentrate and hay to replacement calves, a milk replacer with fish protein concentrate and dried whey gave similar performance to an all-milk milk replacer.