A period of five years (2012-2016) data were utilized to analyze the effect of month and season on hatchability performance of Turkey maintained at Poultry Research Station, TANUVAS, Chennai-51. The per cent fertility, hatchability on total and fertile eggs set and embryonic mortality were worked out from a total of 134 hatches and 26093 of eggs set. The mean per cent fertility and total hatchability were differed significantly (P<0.01) between month and season. Month and season showed no significant effect on dead germ and dead in shell percentage. The per cent fertility and total hatchability was better during monsoon and winter season than summer season. The overall mean fertility, total hatchability, fertile hatchability, dead germ and dead in shell percentage of turkey were 71.61, 46.09, 63.75, 18.25 and 17.79 respectively. The above study concluded that both individual month and season influenced the hatchability performance of turkey eggs.
Fertility and hatchability are the major determinant of profitability in the turkey breeding farming. These parameters appear to be very important as far as parent stocks are kept to produce final hybrids. Hatchability is a complex age dependent trait. It comprises of several sub-traits which are susceptible to genetic and environmental factors arising from various sources (Wolc and Olori, 2009). Turkey egg fertility and hatchability are usually lower in the summer month, when the temperature rises, compared to the other month. Researchers have proved that climate has the direct bearing on the productive and reproductive performance of the animals. Determination of the seasonal effect on hatchability should be given priority because of their adaptability, resistance to disease and successful rearing of turkey. Considering the above circumstances the study was undertaken with a view to determine the effects of month and season on the hatching performance of turkey and to identify suitable hatching month and season of hatching turkey eggs.
Materials and Methods
The hatch data for a period of five years were utilized to analyze the hatchability performance of Nandanam turkey varieties (Nandanam Turkey-I and Nandanam turkey-II) at the age between 30 to 72 weeks maintained at Poultry Research Station, TANUVAS, Chennai-51. Nandanam Turkey-I and Nandanam Turkey-II was evolved by TANUVAS in the year 2006 and 2011 respectively. The standard feeding (adlibitum) and managemental practices were followed thorough out the study period. The eggs were collected every morning, graded, fumigated and stored at 18oC with 80 per cent relative humidity for 7 days; they were brought in to room temperature for one hour and incubated on 8th day and provided optimum temperature and humidity in setter and hatcher. The eggs were turned once in an hour. The eggs were transferred on 25th day to hatcher and turkey poults were taken on 28thday as per the standard protocol. Unhatched eggs were breakout to get infertile and embryonic mortality data. The per cent fertility, total hatchability, fertile hatchability and embryonic mortality were worked out from a total of 134 hatches and 26093 of eggs set. The year was divided in to four different season as winter (January and February), summer (March, April and May), southwest monsoon (June, July, August and September) and northeast monsoon (October, November and December) as per Indian Metrological Department, Pune. All the fertility parameters were expressed in percentage. The data were analyzed by One-way ANOVA as per the procedure of Duncan’s multiple comparison test (Duncan, 1955) after arc-sine transformation.
Results and Discussion
Effect of Month on Hatching Performance of Turkey
The effect of month on hatching performance of turkey is presented in Table 1. The mean per cent fertility and total hatchability were differed significantly (P<0.01) between month. However, month showed no significance influence on fertile hatchability and embryonic mortality. The highest fertility and total hatchability (81.45 and 57.42 % respectively) were found in November and lowest during May month (62.38 and 36.28 % respectively). A raise in fertility and total hatchability percentage were observed from June month onwards and reached peak between October and February then gradual fall was observed up to May. A similar study was carried out by Richard Jagatheesan et al. (2012) in Beltsville Small White, they observed highest fertility and total hatchability during January and lowest during May month. In our study, the lowest fertility and total hatchability observed during May month might be due to temperature rose as reported by Das and Ali (1999).
Table 1: Effect of month on hatching performance (mean ± SE) of turkey
|Hatchability (%)||Embryonic Mortality (%)|
|Total Hatchability||Fertile Hatchability||Dead Germ||Dead in Shells|
n= No. eggs; Mean bearing different superscripts within the same column differ significantly; **Highly significant (P<0.01); NS- Not significant
Effect of Season on Hatching Performance of Turkey
The effect of season on hatching performance of turkey is presented in Table 2. The mean per cent fertility and total hatchability were differed significantly (P<0.01) between season and the values for winter, summer, southwest monsoon and northeast monsoon were 75.37 and 50.87, 64.97 and 40.91, 70.93 and 42.88; and 79.76 and 53.36 respectively. In our study, the rise in fertility and total hatchability were found during southwest monsoon and reached peak during northeast monsoon, then gradually reduced towards winter and lowest during summer season. Hatchability performance observed in our study concurs with the earlier findings of Chowdhury et al. (2004) they observed highest hatchability percentage in winter followed by summer and monsoon/rainy season. Similarly, Hossain et al. (2002) reported that fertility of broiler parent stock was highest in spring, lowest in summer, and intermediate in monsoon and Farooq et al. (2003) observed that the hatchability of chicken eggs was higher in spring (78.0±1.03%) than in summer (46.5±3.01%). Further, the overall fertility percentage observed in this study were similar with earlier workers of Anna Anandh et al. (2012) and Richard Jagatheesan et al. (2012) whose observed on average fertility percentage of 76.78 and 71.03 respectively.
Table 2: Effect of season on hatching performance (mean ± SE) of turkey
|Season||Fertility (%)||Hatchability (%)||Embryonic Mortality (%)|
|(2012-2016)||Total Hatchability||Fertile Hatchability||Dead Germ||Dead in Shells|
n= No. eggs / season; Mean bearing different superscripts within the same column differ significantly; **highly significant (P<0.01); NS- Not significant
The per cent fertile egg hatchability and embryonic mortality did not differ significantly between seasons, however southwest monsoon showed numerically higher embryonic mortality than other season might be due to starting stage of breeding season in turkey. Similarly, Richard Jagatheesan et al. (2012) observed highest embryonic mortality during winter, followed rain/ monsoon and summer season. According to Sastry et al. (1996) temperature was the most critical factor for incubation and the temperature affected both quantity and quality of hatch. The overall mean per cent dead in germ (18.25) and dead in shell (17.79) observed in our study are similar with Anna Anandh et al. (2012) in Broad Breasted Bronze turkey and they observed maximum of 17.44 per cent dead in germ and 21.47 per cent dead in shell. Further, the total embryonic mortality observed in our study was better than Premavalli et al. (2010) who observed a maximum of 42 per cent in turkey.
The above study concluded that month and different season showed significant influence on fertility and hatchability performance in turkey. The overall hatchability performance was better during monsoon and winter season than summer season. Hence, monsoon/rainy and winter season could be considered as a suitable season for hatching turkey eggs.
The authors acknowledge the Tamil Nadu Veterinary and Animal Sciences University, Chennai-51 for providing all facilities to do the work.