The effect of exogenous enzymes on the nutritive value of Camelina, Lunaria, pea and lupin meals for broilers
The nutritive value of seed meal from Camelina sativa, Lunaria biennis, Pisum sativum, Lupinus albus and Lupinus luteus was assessed with and without the addition of exogenous enzymes for growing broiler chickens. The nutritive value of seed meal from camelina and lunaria was found to be low with apparent metabolisable energy (AME) values of approximately 8 MJ kg-1, which is lower than would be expected for other oilseeds such as rapeseed meal. The nutritive value of camelina meal was improved by the addition of phytase and protease but the improvements were not of sufficient magnitude to compete with soyabean meal or rapeseed meal. A poorer weight gain, feed conversion and nutrient digestibility was found when camelina meal was included in the diets of growing broiler chicks compared to birds fed a diet based on soyabean meal. The inclusion of camelina meal detrimentally altered the microbial flora in the caeca and increased the secretion of endogenous material compared to birds fed a wheat/soyabean meal ration. The poor metabolisability of camelina and lunaria is thought to be due to a relatively high concentration of glucosinolates, phytate and toxic fatty acids in the seed meals which impair nutrient retention and increase endogenous losses. The nutritional value of seed meal from Lupinus albus and Lupinus luteus was found to be higher than for camelina and lunaria but poorer than would be expected for soyabean meal. AME values for both lupins were around 10 MJ kg-1 with seed meal from Lupinus luteus proving to have a marginally higher nutritional value than Lupinus albus for broilers. The addition of a cocktail of carbohydrase and protease enzymes did not improve the nutritive value of the seed meal for poultry, both in a precision feeding study and in a growth study where lupin seed meal was included in the diets of broilers at 300g kg-1.