Effect of chromium on performance, meat quality and transcriptional profile analysis of muscle and liver genes of lambs fed high concentrate diets

Abstract

Chromium is an essential trace element for glucose metabolism and there are indications that it increases muscle deposition and alters lipid and protein metabolism. However, little is known about its molecular action, as well as the best dose for ruminants. The objective of this work is to evaluate three doses of chromium compared to control, without additional chromium, on performance, carcass physical composition, meat quality and transcriptional profile of muscle and liver genes of lambs fed high concentrate diets. Thirty-two crossbred Dorper X Santa Inês just weaned lambs (initial live weight of 18 kg) will be distributed in four treatments: control (CTL), without supplementation with chromium picolinate; and chromium picolinate supplementation at 0.4; 0.8 and 1.2 mg / kg DM (CrPIC4, CrPIC8 and CrPIC12, respectively). The animals will be kept in individual pens and fed a diet consisting of 6% roughage (coastcross grass hay) and 94% concentrate. The lambs will have their weight measured every 14 days. After 60 days of feed, the animals will be slaughtered and muscle and liver samples will be collected for transcriptomic analysis. Bone density will be evaluated at the femur. In meat will be evaluated characteristics such as pH, color, tenderness, shelf time, lipid peroxidation and fatty acid profile. Results will be analyzed using SAS version 9.0 software by regression analysis. (AU)