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Circadian rhythm of hyla F1 progeny and grower non- descript rabbits as affected by physiological parameters under the tropical conditions of Nigeria

O. M. Akinsola, B. A. Nwagu, A. Shaibu, G. T. Erakpotobor, E. D. Eze, O. Onaadepo, A. A. Musa, E. U. Okuda, J. B. Suleiman, A. Shaibu


Circadian rhythm of physiological variables such as rectaltemperature (RT), respiratory rate (RR) and heart rate (HR) were evaluated inthe guinea savannah zone of Nigeria on three genetic groups (Hyla purebred,Hyla crossbred and grower non descript rabbits) at 64 days of age. Temperaturehumidity index (THI) was determined from the readings of AT and RH.Physiological and environmental readings were taken at 08:00 h to 10:00h in themornings and 16:00 h to 18:00 h in the evenings from February through November,2011. THI in the mornings was averaged 24.2 o Cwhile evenings THI was averaged 27.8 o C. The THI values estimatedaveraged 27.3 o C during the cool period and 28.7 o Cduring the hot period. Overall, the results obtained indicated that THI in theevening was higher (P < 0.05) by 14% than THI in the morning. Also, THI inthe hot was higher (P < 0.05) than THI in the cool season by 5%.There were significant (P<0.05) differences in the cycle of the day for allthe thermoregulatory parameters (RR, HR, RT and ET) across the studied breed.The grower non descript rabbits showed the least values for both hour of theday for all the thermoregulatory parameters. In conclusion, grower non-descriptrabbits had developed a better mechanism to adapt faster compared to thetemperate Hyla rabbit during both cycles of the day.


Adenkola, A.Y., Ayo, J.O., Sackey, A.K.B., 2009. Ascorbic acid-induced modulation of rectal temperature in pigs during harmattan season. J. Therm. Biol., 34 (3),pp. 152-154.

Encarta Encyclopedia, 2011. Study tools, a Multimedia Encyclopedia, Dictionary and an Atlas. Microsoft Student with Encarta Premium, DVD.

Farghly, M.F.A., 2011. Using light flashes programme as a tool to avoid the hot weather effect on growth performance of New Zealand White rabbits. Egyptian Poul. Sci., 31 (11), pp. 437-451.

Finzi, A., Morera, P., Kuzminsky, G., 1994. Acclimatisation and repeatability of thermotolerance parameters in rabbits. Proceedings of the 4th Congress of the World Rabbit Science Association. Budapest, Hungary, pp. 419-424.

Habeeb, A.A.M., El-Masry, K. A., Aboulnaga, A. I., Kamal, T.H., 1997. The effect of hot summer climate and level of milk yield on blood biochemistry and circulating thyroid and progesterone hormones in Friesian cows. Arab Journal of Nuclear Sciences and Applications 29,pp. 161–173.

Livestock and Poultry Heat Stress Indices, 1990. Agricultural Engineering Guide. Clemson University Press, Clemson Science, 29634, USA.

Marai, I .F. M., Habeeb, A. A. M., 1994. Thermoregulation in rabbits. Options Mediterraneennes: 8, pp. 33–41.

Marai, I.F.M., Ayyat, M.S., Abd El-Monem, U.M., 2001. Growth performance and reproductive traits at first parity of New Zealand White female rabbits as affected by heat stress and its alleviation under Egyptian conditions. Tropical Animal Health and Production, 33, pp. 1-12.

Marai, I.F.M., Habeeb, A.A.M., Gad, A.E., 2002. Rabbits’ productive, reproductive and physiological performance traits as affected by heat stress: a review. Livestock Production Science, 78, pp. 71-90.

Marai, I.F.M., Habeeb, A.A.M., Gad, A.E.,2005. Tolerance of imported rabbits grown as meats animals to hot climate and saline drinking water in the sub-tropical environment of Egypt. Proceedings of the British Society of Animal Science. 81, pp. 115-123.

Okab, A.B., El-Banna,S.G., Koriem, A. A.,2008.Influence of environmental temperature on some physiological and biochemical parameters of male New Zealand rabbits. Slovak Journal of Animal Science 41, 2008, pp 12-19.

Piccione, G., Caola, G.,2002. Biological rhythm in livestock. Journal of Veterinary Science, 3,pp.145-157.

Willmer, P., Stone,G., Johnston, J., 2000. Environmental physiology of animals. 1sted. Blackwell Scientific Publications, Oxford, pp. 672.

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