AMINO-ACID AND ENERGY DIGESTIBILITY IN PEAS (PISUM-SATIVUM) FROM WHITE-FLOWERED SPRING CULTIVARS FOR GROWING PIGS

Six barrows, average initial weight 35 kg, fitted with a simple T-cann ula at the distal ileum, were used to determine the apparent ileal dig estibilities of amino acids (AA) and the digestibility of energy in si x diets according to a 6 x 6 Latin square design. The pigs were fed si x corn starch-based diets formulated to contain 165 g CP per kg from s ix different white-flowered spring pea cultivars. Chromic oxide was us ed as the digestibility marker. The pigs were fed twice daily, at 08:0 0 and 20:00 h. Each experimental period lasted 9 days. Faeces were col lected from 08:00 on day 6 to 08:00 h on day 8; ileal digesta from 08: 00 on day 7 to 08:00 h on day 9. Of the indispensable (+semi-) AA, the re were differences (P < 0.05) in the AA digestibilities of arginine, methionine, phenylalanine and tyrosine between the cultivars. In the s ame order for these AA, the digestibilities ranged from 81.3 to 89.0%, 67.8 to 75.1%, 68.0 to 74.6% and 66.1 to 74.8%, respectively. Within each cultivar, the digestibilities of cysteine and threonine were rela tively low, ranging from 58.5 to 65.9% and from 59.6 to 67.4%, respect ively. The digestibility of lysine was relatively high, ranging from 8 0.3 to 84.0%. The energy digestibilities in the pea cultivars ranged f rom 87.4 to 90.2% (P < 0.05); the digestible energy content from 14.0 to 14.4 MJ kg(-1) DM. There was considerable disappearance of energy i n the large intestine, ranging from 4.4 to 6.2 MJ kg(-1) DM intake fro m peas. In conclusion, when measured with the ileal analysis method, t here were differences (P < 0.05) in the digestibilities of some of the indispensable AA between the pea samples. Furthermore, the relatively low digestibilities of methionine and cysteine further accentuate the limitation of the sulphur-containing AA in protein from peas.