Plant and Animal Origin Protein Supplements on Overall Nutrient Digestibility, Growth and Reproductive Performances of Dairy Calves

This paper represents a review work on the different animal and plant sources of protein supplements for growing calves, comparative nutrient degradabilities and difference in growth and reproductive performances of calves fed with those protein supplements. Animal origin protein sources include meat and bone meal, blood meal, poultry by-product meal (poultry meal) and feather meal. These are all concentrated sources of protein and amino acids and some are also good sources of vitamins and essential minerals. There are many possible sources of plant protein for livestock rations. These include oilseeds, by-products of food production, arable and forage legumes. Animal origin protein supplements in general have better composition and balance of amino acids compared with plant origin proteins. Higher level of rumen undegradable intake protein fractions of animal sourced proteins has been demonstrated. The overall intake, digestibility and performance of calves fed either animal origin or plant origin protein supplements are comparable