Influence of supplementing diet with microalgae (Schizochytrium limacinum) on growth and metabolism in lambs during the summer

Abstract

The current experiment was conducted to examine the impact of a supplement of microalgae (Schizochytrium limacinum) on the performance, rumen fermentation, and blood metabolites in lambs during summer. Forty lambs were used in a 49-day experiment. The lambs were group-fed either a basal diet (alfalfa hay and concentrate, n = 20) or the basal diet along with 5 g/day microalgae (n = 20). Feed intakes were recorded daily and body weight (BW) was measured weekly. Overall, microalgae feeding increased (P < 0.05) the BW and average daily gain. There were no significant differences for average feed intake or feed efficiency (P > 0.05). Microalgae feeding decreased rumen pH (P < 0.05) and tended to reduce proportion of acetate (P < 0.1), while it increased total rumen volatile fatty acid concentration (8.6%; P < 0.01) and proportions of propionate (13.9%, P < 0.01) and valerate (P < 0.01; 26.5%) compared with the control animals. Microalgae feeding increased (P < 0.05) blood glucose (98.47 vs. 84.97 mg/dL) and insulin (64.14 vs. 29.26 ng/mL), whereas it lowered total cholesterol concentrations in blood (62 vs. 58 mg/dL, P < 0.1) compared with the control animals. The results of this study indicate that microalgae supplement influences productivity and enhances dietary energy utilization in lambs during the summer.