Vol. 10, Issue 7 (2021)

Author(s):
Harsha M, Swathi B, Radhakrishna Pulikanti, Rajanna Neeradi, Kannaki TR, Venkata Rama Rao S and Priyanka E

Abstract:
A total of 180 Vanaraja birds aged 8 weeks were divided into six groups viz., three control groups fed on basal feed (BF), Oxycure supplemented basal feed (OX) and Aloe vera supplemented basal feed (AV) and their corresponding treatment groups BFHS, OXHS and AVHS. Treatment birds were subjected to heat-stress (38°C and 40% Relative Humidity (RH); Temperature-Humidity Index, THI=86), for four hours daily for a period of four weeks in an environment-controlled chamber. Control birds were maintained at ambient conditions throughout the trial period (mean THI=78.29). The magnitude of humoral immunity decreased significantly (P≤ 0.01) after four weeks of heat-stress and dietary supplementation of Oxycure had minimal impact. The cell mediated immunity also decreased significantly (P≤ 0.05) on exposure to heat-stress and dietary supplementation of either Oxycure or Aloe vera failed to improve it. Both duodenal and ileal mean villi heights were significantly (P≤ 0.01) greater in control birds fed on Aloe vera supplemented feed. Supplementation of feed with either Aloe vera or Oxycure yielded relatively higher duodenal and ileal villi heights and villi height to crypt depth ratios in heat-stressed subjects. Furthermore, heat-stress has significantly increased the number of harmful (E. coli and Salmonella) and decreased the number of probiotic (Lactobacillus) bacteria in the intestines. Dietary Aloe vera supplementation has also positively influenced the gut-microbiota in heat-stressed birds.