Chromium yeast affects growth performance but not whole carcass composition of growing-finishing pigs

An experiment with 40 pigs (24.5 kg initial and 105.5 kg final live weight) was conducted to investigate the effects of supplemented trivalent chromium (Cr) from chromium yeast on growth performance, carcass composition, fatty acid profile of the carcass fat, and blood parameters both after a 24-h fasting period and 2 h after feeding. Ten pigs per treatment were fed a barley-wheat-soybean meal diet supplemented with either 0 (C), 200 (C200), 400 (C400) or 800 ppb Cr (C800) at a restricted feeding scale. Pigs receiving the C200 treatment snowed both improved average daily gains and feed conversion ratios compared to those receiving treatment C for the total experiment (P < 0.06), especially in the finishing period. While carcass measurements and composition, as well as the fatty acid profile, were not significantly affected by the Cr supply, concentrations of plasma insulin, triglycerides, non-esterified fatty acid (NEFA), urea N and ketone bodies gave evidence that supplemented Cr affected carbohydrate and fat metabolisms. The failure of plasma metabolite changes to be reflected in the whole body composition may have been dependent on the genotype (lean in this experiment) and the manner of feeding (restricted feeding scale in this experiment vs. ad libitum in other reported experiments). (