TRYPSIN-INHIBITORS IN PEAS - VARIETAL EFFECT AND INFLUENCE ON DIGESTIBILITY OF CRUDE PROTEIN BY GROWING PIGS

The trypsin inhibitor activity (TIA) of 33 European spring pea varieties was determined. The TIA ofthe varieties Maro, Progreta, Consort and Radley ranged from 6.1 to 8.4 trypsin inhibited units per mg dry matter (TIU mg-1 DM), whereas all the other varieties had ≤ 3 TIU mg-1 DM. Maro, Progreta and Consort are British varieties of the 'marrowfat' type which have classically a high activity. The French winter varieties had a high TIA (mean, 9.1 TIU mg-1 DM), but the varieties arising from a cross between a winter and a spring variety, such as Frilène, Amac, Laser and Santon, had a lower activity. The results were compared with those obtained for six other legume seeds: faba beans, vetches, lentils, pigeonpeas, chickpeas and haricot beans. Finally, a comparison of the TIA of samples of the variety Finale originating from different fields showed that growth conditions influenced the pea TIA. The apparent digestibility of the main constituents of two spring pea varieties (Finale, 2.35 and Progreta, 7.48 TIU mg-1 DM) was determined, by the difference method, using growing pigs with diets consisting of 40% peas. The apparent digestibility of organic matter, crude fibre and crude energy was similar for the two varieties, whereas the apparent digestibility of the crude protein of Progreta was significantly lower (P < 0.05) than that of Finale. The influence of trypsin inhibitors on the apparent digestibility of crude protein was discussed and all other hypotheses which could explain this difference were considered. © 1990.