Supplementing Lactobacillus brevis metabolite modifies carcass performances, characteristics of meat, taste-related compounds and fatty acid profiles of heat stressed Chikso cattle.

Abstract

This study aimed to evaluate the effects of purified Lactobacillus brevis metabolite (LBMs) supplementation on growth performance, carcass traits, and meat quality in Chikso cattle subjected to heat stress. Twenty-seven Chikso steers with an average initial body weight of 499±15 kg were randomly assigned to three treatment groups: a basal diet control (CG), and basal diets supplemented with either 150 mg/kg (LGS) or 300 mg/kg (HGS) of purified LBMs. The feeding trial lasted for 120 days under summer heat stress conditions. Both LBMs-supplemented groups exhibited significant improvements in average daily gain, with 0.89 g/d (LGS) and 0.81 g/d (HGS) compared to 0.52 g/d in controls (p<0.05). Total weight gain increased by 71% and 56% in LGS and HGS groups, respectively. Meat protein content was significantly higher in LGS (18.97%) and HGS (18.37%) than in CG (17.23%) (p<0.05). Supplementation enhanced water holding capacity and reduced cooking loss to 26.13% from 31.09% in controls (p<0.05). Antioxidant enzyme activities of catalase and superoxide dismutase were elevated in the treatment groups throughout cold storage (p<0.05), with lipid oxidation significantly inhibited from day 3 onward (p<0.05). LBMs also increased oxymyoglobin percentages, indicative of improved meat freshness, and favorably altered fatty acid profiles by decreasing saturated fatty acids and increasing eicosapentaenoic acid levels. Carcass characteristics, however, remained unaffected. Rumen-protected LBMs supplementation effectively enhances growth performance and meat quality in heat-stressed Chikso steers. These benefits likely arise from improved antioxidant capacity, reduced oxidative stress, and modulation of fatty acid composition. This strategy holds promises for improving livestock resilience to climate challenges and warrants further research.