Effects of Seasonal Variation on Egg Production of Sonali Chicken

Abstract

Egg production, mortality rate and feed consumption data of Sonali chicken was obtained from 5 different flocks of the Mirshorai Poultry Farm and Hatchery in Mirshorai upazilla under the district of Chittagong, Bangladesh, over a four-year period (2007 - 2010). The data were subjected to least squares analysis to determine the effects of age, season and year. It was demonstrated that age had a highly significant influence (P<0.05) on egg production in that birds falling within the age group 31 - 37 weeks produced the highest number of eggs (8130.96 ± 271.61), while birds falling within the age group 67 – 71 weeks age produced the least number of eggs (4056.96 ± 203.35). The seasonal variation in egg production was also highly significant (P<0.05); the highest egg production (8238 ± 90.15) was obtained during the season of March-May, and the lowest (5920.08 ± 550.20) during the season of September-November. Mortality was generally low (1.5 - 3.11%) and significantly different (P<0.05) from 24 - 44 weeks of age. However, from 45 to 71 weeks of age, highly significant differences (P<0.05) in mortality was observed within 67 - 71 weeks age group recording the highest mortality of 12.83 ± 1.65%. The age group of 24-30 wks and 38-44 wks (149.5 ± 1.08 and 148.14 ± 0.40 respectively) showed no significant variation at all. But it differs from the age group of 31-37 wks. The age group of 45-51 wks, 52-58 wks and 67-71 wks had not shown any significant variation in feed consumption. Furthermore, yearly variations in egg production and mortality were not significant (P<0.05) with the year of 2007, producing the most eggs (6419.83±275.16) and in the year of 2009 recording the least mortality (2.37±0.34). It was concluded that due to the significant age and seasonal variation on egg production, but not yearly variations, data on egg production and mortality need to be adjusted for these effects for unbiased comparison between and within the flocks of the farm.