Tannin content affects negatively nutritive value of pea for monogastrics

Nine Polish varieties of pea (P. sativum L.) differing in flower colour, fr om white to purple, were evaluated for chemical and amino acid composition and in vitro for predicted ileal digestibility of protein (pdN) and predict ed digestibility of energy (pdE) for pigs. In selected varieties differing in tannin content the apparent metabolizable energy value corrected for zer o N balance (AME(N)), apparent digestibility of protein and fat and effect of enzymes reducing viscosity of digesta on this parameters were estimated in chickens; apparent metabolizable energy value (AME), true digestibility and biological value of protein was determined in rats. Tannin content had most pronounced negative effect an protein digestibility in chicken (r=-0.93; P <0.05) and rats (r=-0.89; P <0.05), pdN for pigs (r =-0.98; P <0.001) as well as AME N for chicken (r=-0.99; P <0.001) and AME for rats (r=-0.95; P <0.01), while nutrient content in peas had no signific ant effect on measured parameters. AME(N) values of pea did not depend on s upplementation of pea-containing diet with xylanase. Seeds of coloured-flowered cultivars, which are rich in tannins are less ef fectively utilized by monogastric animals than white-flowered ones. The deg ree of decline in nutrient utilization depends on tannin content in the see ds, which is correlated with the colour of the flowers.