Studies on the effects of feeding yellow pea (Pisum sativum L. var. Miranda) diets with and without supplementation to commercial broiler chickens

Five experiments were conducted with commercial broilers to study the effects of feeding yellow pea (Pisum sativum L. var. Miranda) diets with and without supplementation. Mean body weights and feed conversion for broilers fed 0, 25, 50 and 65% of soybean crude protein (CP) substituted with yellow pea (YP) protein were not significantly different among the dietary treatments at 4-weeks of age (WOA). At the end of 7 WOA broilers fed 50 and 65% YP diets had significantly lower mean male, female and combined sex body weights than broilers fed the 0 (C-S) and 25% YP diet. Feed conversion for broilers fed the 65% YP diets was significantly higher than for broilers fed the 0 (C-S), 25 and 50% YP diets (Experiment 1). Commercial broiler chicks grown in cages with raised wire floors from day-old to 4 WOA (Experiment 2) and from day-old to 7 WOA (Experiment 3) were fed YP diet without and with supplementation of either choline (.12%) or a dl-methionine (.4%) or a combination of the two. Autoclaved YP was also fed which represented 50% of the CP from soybean meal. Feeding diets containing 25 and 50% YP did not significantly depress either growth rate or improve feed utilization when compared to broilers fed the 0% YP diet. Supplementation of choline (.12%) or dl-methionine (.4%) or the combination of the two to 50% YP diet and feeding autoclaved 50% unsupplemented YP diet did not significantly improve performance. Broiler chicks were reared on litter floors (Experiment 4) and fed diets containing 0, 25 and 50% YP and 50% YP diets with supplemental 1-tryptophan (.045%) to 7 WOA. At 4 and 7 weeks, significant improvements in mean male body weights were observed with supplemental 1-tryptophan to the 50% YP diet then with the unsupplemented 50% YP diet. No significant difference was observed in combined body weights, mean female body weights and feed conversion at 4 and 7 WOA among broilers fed 50% YP with and without 1-tryptophan supplementation. Performance of broilers fed 0 and 25% YP diets were not significantly different at 4 and 7 WOA. Supplementations of either 1-tryptophan (.01%) or 1-threonine (.03%.) or 1-lysine (.1%) or combinations of two or three amino acids to 50% YP diets were carried out (Experiment 5). At 4 WOA, supplementation of tryptophan and threonine to 50% YP diet significantly improved body weight more than did the unsupplemented 50% YP diet. Supplementations of either tryptophan or threonine to 50% YP diets did not produce significant differences in mean body weights than the 25% YP diet. Lower body weight was observed with lysine supplementation than with other dietary treatments at 4 WOA. At 7 WOA, supplementation of threonine alone or combination of threonine and tryptophan to 50% YP diets produced comparable growth performance with that of broilers fed 0% and 25% YP diets. Lysine supplementation to the 50% YP diet produced lower body weights than the other dietary treatments. No significant differences in body weights were observed among the broilers fed the 50% YP diets supplemented with tryptophan alone or a combination of either lysine with tryptophan or threonine or all three amino acids when compared with 50% YP diet. Feed conversion was not significantly different among the dietary treatments at 4 and 7 WOA. Feeding of 25% YP diet was not detrimental to broiler growth and feed conversion. Supplementation of either tryptophan or threonine or the combination of the two to the 50% YP diet improved body weights. However, lysine, methionine and choline supplementations did not improve broiler performances