Evaluation of whole soybeans in swine diets

A laboratory assessment and three in vivo trials were conducted to measure the nutritive value of whole soybeans subjected to various methods of heat treatment. No significant differences were found for ADG and feed conversion ratio. There was a significant reduced proportion of saturated-to unsaturated fatty acids in the loin eye area of pigs fed whole soybean products, when compared to soybean meal control. Extruded whole soybeans resulted in a lower degree of unsaturation than the other heat treated whole soybeans. Whole soybean products were evaluated for their digestibility in weanling (21 days) piglets. Feces were collected daily during two 5-day periods. It was found that the ether extractable portion of extruded whole soybeans has a higher digestibility than that of the remaining four soybean treatments. It was also found that CP is more digestible in animals at 6 weeks of age than in animals at 4 weeks of age. In conclusion: heat treated whole soybeans do not adversly affect the performance of weaners nor that of growing and finishing pigs, even at high dietary levels (25%). Feeding whole soybeans results in a higher degree of unsaturation in the carcass. The EE fraction of extruded whole soybeans is more digestible than whole soybeans of other heat treatments. (Abstract shortened by UMI.