Digestibility and availability of amino acids from feedstuffs for pigs: a review

Measurements of the digestibility and availability of amino acids in feedstuffs should predict the ability of feedstuffs to supply amino acids to pigs in forms suitable for protein synthesis. Some of the methods available for such measurements are discussed; further work is needed to establish their reliability for predicting production responses to feedstuffs. At present the nitrogen balance technique appears to be the most useful, though indirect, method of evaluating feedstuffs as sources of amino acids.