Date of this Version
Two experiments were conducted to investigate the effects of a corn-soybean meal (CSBM) and a sorghum-soybean meal (S-SBM) diet on reproductive performance and nutrient utilization by sows. In Exp. 1,75 sows (39 gilts; 36 primiparous) were fed either a C-SBM or a S-SBM gestation diet from breeding to d 109, On d 110, sows were assigned to lactation diets; half of the sows from each dietary treatment were assigned to a lactation diet based on the opposite grain. Sow weight change from d 54 to farrowing was greater (P < .06) for sows fed S-SBM than for sows fed C-SBM. There was no difference (P > SO) in weight change of sows during lactation. Feed consumption during lactation was greater (P < .01) for sows fed C-SBM than for sows fed SSBM. Litter size at birth and d 21 did not differ between treatments (P > .13). Litter weights at birth were similar, but litters of sows fed C-SBM gained more weight (P < .05) during the 21d lactation than those fed S-SBM. There were no differences (P > .30) in the number of days from weaning to estrus. In Exp. 2, the energy and N metabolism of the two diets was compared in 12 lactating, primiparous sows from d 15 to 20 of lactation. Dry matter digestibility, DE and ME percentages were not affected by grain source (P > .46). Apparent N digestibility, apparent biological value and N balance were higher for the C-SBM than for the S-SBM diet (P < .05). Sows fed the CSBM diet during lactation consumed more feed, utilized more of the dietary N and had litters with greater weight gains than sows fed the S-SBM diet.