Haemagluttinins and Trypsin Inhibitors in Some Tropical Legume Seeds: their Significance in Animal Nutrition – A review

Abstract

Legumes are important source of protein and energy in the diet of farm animals. The use of legumes for livestock nutrition is however, impeded by the presence of antinutritional substance in their seeds. The most important ones include haemagglutinins and trypsin inhibitors. Haemagglutinins adversely affect the absorption of nutrients from the intestinal tract, agglutinates the erythrocytes, induces severe reduction in feed intake and depresses growth. Trypsin inhibitors negatively affect proteolytic activity of the digestive enzyme trypsin which can lead to reduction in the availability of amino acids, induced pancreatic hypertrophy and depressed growth. Inactivation of these undesirable substances in legume seeds is essential in order to improve their nutritional quality in livestock feeds. This paper high-lights the contents, nutritional significance and effects of processing (roasting, cooking and autoclaving) on haemagglutinins and trypsin inhibitors in some tropical legume seeds such as African yam bean (Sphenostylis stenocarpa), bambaranut (Voandzeia subterranea). kidney bean (Phaseolus vulgaris L.), Lima bean (Phaseolus linatus L), pigeon peas (Cajanaus cajan L. Millsp), and jack bean (Canavalia ensiformis). The application of moist heat has been found to be the most efficient method of inactivating haemagglutinins and trypsin inhibitors in these legume seeds.