The role of selenium in ameliorating the impact of heat stress on growth, hormones, minerals and tibia measurements of broiler chickens. (Special Issue: Covid-19 and climate change.)

Ndubuisi, D. I.; Daudu, O. M.; Abdulrashid, M.

The study was conducted to investigate the potent capacity of selenium to curtail the adverse effects of heat stress in broiler chickens. A total of 256, day old Cobb 500 broiler chicks were randomly allotted to four experimental treatments (0, 0.1, 0.2 and 0.3 mgSe/kg), with four replicates in a completely randomized design. Initial weight, daily feed intake, daily weight gain, final weight, feed conversion ratio, daily water intake, feed cost/kg gain, mortality, serum cortisol and thyroxine levels, calcium, phosphorus and ash levels in tibia bone and faeces and weight, length and robusticity index of tibia bone were determined. Results indicated that Initial weight, daily feed intake, daily weight gain, final weight, feed conversion ratio, daily water intake and mortality were similar (p>0.05) across the treatment groups and feed cost/kg gain was lower in broilers birds fed 0.3 mgSe/kg. Selenium supplementation at 0.1 and 0.2 mgSe/kg lowered (p< 0.05) cortisol and increased (p>0.05) thyroxine level, respectively. Mineral deposition in tibia bone was similar (p>0.05), calcium excretion was higher (p< 0.05) in the control group and higher phosphorus was observed in the faeces of broilers fed the control diet, 0.1 and 0.3 mgSe/kg. Tibia measurements were similar (p>0.05) in all treatments.