Effect of calcium propionate level on the growth performance, carcass characteristics, and meat quality of feedlot ram lambs

Abstract

This study aimed to evaluate the effect of three oral doses of the glucogenic precursor calcium propionate (CaPr) on the growth performance, blood metabolites, carcass characteristics, and meat quality of finishing lambs, during 42-day feeding trial. Basal diet contained 16.3 % crude protein (CP) and 5.4 MJ/kg NEg. Thirty-six (35 ± 0.6 kg BW) Dorper × Katahdin lambs (9 lambs per treatment) were randomly assigned to treatments (CaPr levels at 0, 10, 20, and 30 g/lamb/day). The final weight, average daily gain (ADG), dry matter intake (DMI), and gain to feed ratio (G:F) were improved by CaPr supplementation, being optimal at the dose of 10 g/lamb/day (quadratic component, P < 0.01). Most blood metabolites were unaffected (P> 0.05), but BUN and BUN:Cr showed a quadratic tendency (P = 0.08) to increase with a supplementation level of 20 g/lamb/day. The CaPr supplementation increased empty body weight (EBW) (P < 0.03), reduced cooling loss (P < 0.05), and tended (P < 0.09) to increase quadratically cold (CCW) and hot (HCW) carcass weights at a dose of 20 g/lamb/day. Lambs fed CaPr had greater (P = 0.03) heart and small intestine mass (g/kg of EBW) and tended (P = 0.07) to have a greater liver mass without affecting other organs. Purge loss, cook loss, and water holding capacity (WHC) were unaffected (P> 0.05), but the shear force (WBSF) increased quadratically (P < 0.04) with maximal value at a dose of 20 g/lamb/day. The increase in the CaPr dose affected (P < 0.05) the meat color values ​​(L *, a * and b *), which was paler at a dose of 30 g/lamb/day. Results indicate that CaPr can be included in a dose of 10 g/lamb/day to improve growth performance and up to 20 g/lamb/day to maximal effects on carcass characteristics.