The impact of probiotic live yeast in a barley grain-based diet on feed efficiency, carcass traits, and immune-oxidative status of artificially reared lambs

Abstract

This study aimed to investigate the effect of dietary supplementation with a probiotic live yeast Saccharomyces cerevisiae on growth performance, carcass traits, and immune-oxidative status in artificially reared lambs. After colostrum administration, pure Chios lambs (n = 42) were divided into two homogenous groups (n = 21); the Control (CON) and Probiotic supplemented group (PROB), were artificially reared until the 45th day of lambs’ age. From the 30th until the 106th day of lambs age, both groups were fed alfalfa hay and a barley grain-based concentrate mix ad libitum. Moreover, 100 g of concentrate including 0.1 g of Saccharomyces cerevisiae CNCM I-1077 live yeast (1010 CFU/g) was offered to PROB lambs to ensure a constant intake of the yeast. The yeast supplementation did not affect animal growth performance. The weight (g/100 g of BW) of the liver was higher in the CON lambs compared to the PROB-fed (P < 0.001). The overall carcass quality was improved in the PROB lambs as reported by lean color, fat color, fat firmness, carcass wetness, and overall acceptability (P < 0.001). Moreover, the Semimembranosus muscle redness (P = 0.025) and yellowness (P = 0.004) were higher in the PROB carcasses compared to the CON-fed. Blood IgA tended to decrease (P = 0.074) only on the 100th day of age of the PROB-fed lambs. The mRNA levels of IL1B were downregulated in monocytes (P = 0.065) and neutrophils (P = 0.001) of the PROB-fed lambs throughout the experimental period. A downregulation was also observed for IL10 in monocytes (P = 0.006) and neutrophils (P = 0.017) of the PROB-fed lambs. The mRNA levels of IL8 were also downregulated (P = 0.012) in the neutrophils of PROB-fed lambs. In conclusion, beyond the animal performances and carcass traits, the formulation of a barley grain-based concentrate mix might induce an inflammatory response that in the case of PROB-fed lambs was more attenuated.