Effect of Relative Humidity on the Performance of Nera Black Hens in a Humid Tropical Environment
M. O. Okpara *
Department of Animal Nutrition and Forage Science, Michael Okpara University of Agriculture, Umudike, Nigeria
C. F. Egbu
Department of Animal Science, University of Nigeria, Nsukka, Nigeria
A. O. Ani
Department of Animal Science, University of Nigeria, Nsukka, Nigeria
*Author to whom correspondence should be addressed.
Abstract
A total of seventy five Nera Black hens in their 4th week of lay were used in a study conducted to determine the effect of different relative humidity conditions on the performance of Nera Black hens under humid tropical environment. Hens were housed individually in separate cages. The hens were supplied with water ad libitum and fed on layers mash containing 16.5% crude protein and 2650 kcal/kg of metabolizable energy for 10 weeks. Relative humidity was recorded 3-hourly at time intervals of 0600 h, 0900 h, 1200 h, 1500 h, and 1800 h using a standard hygrometer and the mean daily relative humidity was noted. The climatic data taken during the period of the experiment showed that the study area had the natural day-length of 13 to 14 hours; mean maximum weekly indoor and outdoor temperatures of 27.90C to 29.20C and 26.80C to 30.50C, respectively; mean minimum weekly indoor and outdoor temperatures of 20.50C to 22.30C and 20.00C to 23.600C, respectively; mean weekly relative humidity of 74.4% to 76.4% and mean total monthly rainfall of 781.33 mm. Results showed that relative humidity significantly affected total egg production, average daily feed intake, egg weight, egg shell weight and Haugh unit. The results of the present study indicate that although relative humidity had effect on performance, Nera Black hens are adapted to humid tropical environment.
Keywords: Egg production, environment, feed intake, relative humidity, temperature