Diurnal and seasonal fluctuations in cloacal temperature in helmeted guinea-fowl (Numida meleagris) and the effect of ascorbic acid

ABSTRACT

The study evaluated ascorbic acid (AA) effects on diurnal fluctuations in cloacal temperature (CT) in guinea-fowls. Twenty guinea-fowls were each assigned to two groups: Group I was administered with distilled water and Group II was treated daily with AA (50 mg/kg) orally. Measurements of dry-bulb temperature (DBT) and relative humidity (RH), to obtain temperature-humidity index (THI), and CT of each guinea-fowl were taken concurrently in the pen thrice a day for 3 days, 1 week apart, during the rainy, cold-dry (harmattan) and hot-dry seasons. Values of THI during the rainy (26.16 ± 0.36) and hot-dry (28.50 ± 1.11) seasons were above the thermoneutral zone for avian species (21), indicating that the guinea-fowls were exposed to heat stress in the seasons. Values of CT were higher (P < 0.05) in controls than experimental guinea-fowls (rainy, 42.17 ± 0.06 vs 42.04 ± 0.08; hot-dry, 42.78 ± 0.11 vs 42.52 ± 0.04°C) and were outside the normal range for avian species. Administration of AA modulated CT fluctuations by decreasing the values in hot-dry season. In conclusion, the hot-dry season was the most stressful for guinea-fowls, and AA modulated considerably CT fluctuations during the season.

KEYWORDS:

• Heat stress
• cloacal temperature
• guinea-fowls
• ascorbic acid

Acknowledgments

We thank the academic and technical staff of the Department of Veterinary Physiology, and Livestock Section, Samaru College of Agriculture, Ahmadu Bello University, Zaria for technical assistance.

Disclosure statement

No potential conflict of interest was reported by the author(s).