Effect of supplemental levels of chromium picolinate on the growth performance, serum traits, carcass characteristics and lipid metabolism of growing-finishing pigs

This study investigated the effect of chromium picolinate supplementation o n growth performance, carcass characteristics and lipid metabolism of growi ng-finishing pigs. Sixty Landrace x Yorkshire x Duroc (LYD) pigs with a mea n initial body weight of 46.65 (s.e. 6.72) kg were randomly allocated into three groups with two replicates. They were supplemented with 0, 200, or 40 0 mug/kg (ppb) chromium in the organic form of chromium picolinate for 90 d ays. Supplementation with chromium picolinate in the pigs' ration improved their growth performance, enhanced average daily gain (P < 0.05), and incre ased their food consumption, especially in the 200 ppb group (P < 0.05). Ch romium picolinate supplementation also improved carcass characteristics, as the average back fat thickness was reduced and the loin-eye area was enhan ced (P < 0.05). The serum chromium concentration in the chromium picolinate supplemented groups was approximately twice that of the controls (P < 0.05 ). Supplementation with chromium also markedly reduced serum total choleste rol, triacylgycerol (TG) and urea concentrations in the pig serum (P < 0.05 ). Serum insulin was significantly decreased in the 400 ppb group, while se rum glucose was decreased in the 200 ppb group (P < 0.05). Very low density lipoprotein (VLDL) was reduced and low density lipoprotein (LDL) was incre ased in the chromium supplementation group. Meanwhile, the high density lip oprotein-cholesterol and VLDL-cholesterol were markedly increased, while LD L-cholesterol was significantly diminished (P < 0.05) in the 200 ppb group. The adipocyte diameter and volume in the chromium-supplemented groups tend ed to be larger than in the control (P = 0.07). In vitro studies indicated that incorporation of [u, C-14]glucose into total lipids (P < 0.05) was inc reased by chromium supplementation. However, there were no lipolysis differ ences among the groups (P > 0.05). The carcasses of the pigs that received the chromium supplemented ration contained less oleic acid (C18 : 1) and to tal unsaturated fatty acids (P < 0.05). On the other hand, the total satura ted fatty acid content was higher than that of the controls (P < 0.05). Res ults in this study demonstrate that chromium picolinate supplementation in pigs has several beneficial effects.