Extremes of climate and hypobaric hypoxia cause poor growth performance in broiler chickens at high altitude and the present study investigates the effect of aqueous extract of Salix alba leaves on growth performance, antioxidant level and immune status of broiler chickens reared at high altitude cold desert (3500 m). High performance liquid chromatography (HPLC) analysis of the extract revealed the presence of salicin and caffeic acid. In vitro efficacy evaluation revealed that the extract had a significant cytoprotective effect on lymphocytes. For in-vivo study, a total of 105 one d old RIR cross-bred broiler chickens were randomly assigned to seven groups: 1) Control fed basal diet and 2) Six treatments fed basal diet + S. alba extract @100, 150, 200, 300, 400, and 800 mg kg−1 body weight of chicken, respectively. Chickens in the Salix 300 group had greater body weight (p < 0.05) and improved feed conversion ratio (FCR) compared to other treatments. Furthermore, chickens had greater (p < 0.05) total antioxidant capacity (TAC), free radical scavenging activity, interleukin-2, and lower malondialdehyde (MDA), interleukin-1, and interleukin-6 concentration as compared to the control group. Net profit was also increased in all the treatments that were fed diet with S. alba extract due to less mortality in chickens. These findings indicated that inclusion S. alba extract at dose concentration of 300 mg kg−1 body weight of chicken, exhibited a beneficial effect on growth performance through immunomodulation and up-regulation of antioxidants, and therefore, it has a potential to be used as a phytogenic feed additive for improving broiler performance at high altitude.
Keywords: Antioxidant, Broiler chickens, Growth performance, High altitude, Immune responses, Salix alba.
Abstract published in Biologia volume 76, pages3003–3015 (2021). https://doi.org/10.1007/s11756-021-00795-w.