Effect of Grain Source, Level of Solka Floc and Caloric Content of the Diet on Performance, Blood and Bone Traits of Growing-Finishing Swine

Abstract

Two trials were conducted with 312 crossbred pigs to determine the effect of grain source, level of Solka floc and energy content of the diet on performance, bone integrity and certain blood constituents of growing-finishing swine. In both trials, pigs fed grain sorghum gained faster (P<.05), ate more (P<.05) feed and had a poorer (P<.05) feed conversion ratio than pigs fed corn. Pigs fed diets containing Solka floc had lower (P<.05) average daily gains and a poorer (P<.10) feed conversion ratio than pigs fed diets with no Solka floc. Feed consumption was depressed (P<.05) in pigs fed Solka floc in trial 1, but was not affected by similar Solka floc levels in trial 2. Pigs fed isocaloric diets gained more (P<.01), ate less (P<.01) feed and had a better (P<.01) feed conversion ratio than pigs fed nonisocaloric diets. Analysis of blood constituents from multiple bleedings in both trials showed that pigs fed grain sorghum had lower (P<.05) serum Ca concentrations and tended to have lower serum alkaline phosphatase concentrations than pigs fed corn. In trial 1, pigs fed grain sorghum had higher (P<.05) serum P concentrations than pigs fed corn, but sources of grain had no effect on serum P of pigs in trial 2. Serum P increased linearly (P<.05) and serum Ca decreased linearly (P<.05) as dietary level of Solka floc increased (trial 1). In trial 2, the addition of Solka floc to the diet resulted in a decrease in serum P concentrations in pigs fed nonisocaloric diets but caused an increase in pigs fed isocaloric diets. Serum Ca and alkaline phosphatase concentrations were not affected by level of Solka floc or caloric content of the diet. Temporal patterns of serum variables were not affected by dietary treatments. Breaking strength characteristics of the metatarsal bones increased linearly (P<.05) as dietary level of Solka floc increased in trial 1, but were not affected in trial 2. In both trials, metatarsals from pigs fed grain sorghum had greater (P<.10) peak force than pigs fed corn. Physical measurements of metatarsals in trial 1 showed that pigs fed grain sorghum had greater (P<.05) length, weight and wall thickness than pigs fed corn. These differences were not observed in trial 2.