Effect of Rearing Systems on Reproductive Performance of Turkey

The objective of this study was to determine the effect of rearing systems on reproductive performance of turkey (Meleagris gallopavo). A total of 180 Beltsville Small White and Board Breasted Bronze turkeys were taken for the study and reared under three different rearing system viz. intensive system (full confinement), semi-intensive system (partial confinement and partial day scavenging) and free range system (all-day scavenging). Average egg weight (g), percentage of infertile eggs, embryonic mortalities, total egg hatchability, fertile egg hatchability, fertility and poults survivability values were significantly (P>0.01) higher in turkeys reared under intensive system of management followed by semi intensive system and free range system of management. The highest percentage of dead in shell was found in intensive system and was did not differ significantly from semi intensive and free range system. Hatched weight of poults (g) between semi intensive and intensive system did not differ significantly between them, but both groups found statistically significant (P>0.01) from free range system. From the study, it is concluded that higher reproductive performance was obtained in intensive system of management followed by semi intensive and free range system of management.


Introduction
poor egg holding period, imbalanced nutrition, stressful conditions the parent flock was exposed to The turkey (Meleagris gallopavo) a well known rearing condition.Low fertility and high embryonic bird in western countries, but in the rest of the world mortality values have been reported in traditional especially in developing countries it is yet to be chicken rearing (Hocking et al., 2007).This can be established on commercial point of view.Commercial explained by poor management practices, mating turkey farming is becoming popular in India and behavior or reproductive physiology in flocks often farmers started to show interest in rearing turkey birds.maintained in small groups.The bird is quite suitable for upliftment of small and Since scanty published literature is available on marginal farmers as it can be easily reared with little hatching performance of turkey birds under different investment for housing, equipment and management.rearing systems in India, the present study was One of the main objectives in turkey breeder conducted to determine the effects of rearing system production is to increase the number of poults on the reproductive performance of turkeys as well as produced.Egg yields in turkeys are lower than that of to identify the suitable rearing system for rearing turkeys.other poultry species.In addition to low egg yield, unsatisfactory egg fertility and hatchability constitute Materials and Methods a major problem for turkey breeding enterprises Experimental design and management: The (Ozcelik et al., 2009).Egg weight, fertility and study was conducted at Turkey Research Unit of embryonic mortality would influence overall hatching TamilNadu Veterinary and Animal Sciences University performance provided management conditions are not -Regional Research Centre, Pudukkottai, Tamil Nadu, the limiting factors.Egg weight, fertility, hatchability India during the year 2010 -11.Beltsville Small White and late embryonic mortality varied greatly between and Broad Breasted Bronze turkeys at an age of 28 traditional and modern breeding management system weeks, 180 breeders were assigned to the three (Lariviere et al., 2009).Variations in fertility, hatchability, treatments in a completely randomized design with embryonic mortalities and survivability may be due to two replicates, for an experimental period of 20 weeks.performances were calculated and included total egg The birds under treatment group I were reared in hatchability (poults hatched / total eggs set x 100), intensive system (full confinement), birds under fertile egg hatchability (poults hatched / fertile eggs set x 100) and fertility (total eggs set -infertile eggs / total treatment group II were reared in semi-intensive eggs set x 100) of each rearing systems were calculated.system (partial confinement and partial day scavenging) and birds under treatment group III were Statistical analysis: The data generated from each reared under free range system (all-day scavenging) of experimental group were analyzed statistically by management and the birds maintained under standard following standard procedures (Snedecor and management practices.Each group was housed in Cochran, 1989) for comparing the means and to separate experimental houses whose floors were determine the effect of rearing systems.raised and covered with sawdust litter.Free mating

Results and Discussion
was allowed in the flock and the sex ratio was 1:4.
Feed containing 15.5% crude protein and 2750 Effect of rearing system on egg weight, kcal/kg energy was fed ad libitum to the birds reared percentage of infertile eggs, embryonic mortalities, under intensive and semi intensive system of dead in shell, total egg hatchability, fertile egg management and in free range system 100 g/day of a hatchability, fertility, poults hatched weight and poults concentrate feed provided.Fresh water was made survivability of turkey are presented in Table 1.The available to the birds throughout the day.The eggs mean ± SE average egg weight in the free range, semi were collected, randomly selected, weighed.The intensive and intensive system were found to be 68.72 collected eggs were stored at room temperature for ±0.15, 70.56±0.13and 72.70±0.18,respectively.The about 3-5 days and then used for incubation.Proper average egg weight between each rearing system cleaning, disinfection and fumigation were conducted differ significantly (P>0.01) between them.The 0 before setting of eggs.The temperature of 99.5 F in highest average egg weight was found in intensive 0 dry bulb and relative humidity of 87.0 F in wet bulb system of management followed by semi intensive were set to incubate the eggs for 25 days during which and free range system.Ramlah (1996) also reported they were rotated hourly interval.increased egg weight in hens reared under intensive Thereafter, these eggs were transferred to the system of management as compared to semi intensive 0 hatcher where temperature 98.5 F in dry bulb and system of management.0 relative humidity of 90.0 F in wet bulb were maintained.
The mean egg weight obtained in the present Hatching started on the day 27 and was completed by study is in accordance with the findings of Ozcelik et th the end of the 28 day.The process used, fumigation, al., (2009) who reported the mean weight of turkey storage conditions, machine conditions were uniform eggs ranged 67.4 to 70.3 g.The mean ± SE percentage for all experimental groups. of infertile eggs in the free range, semi intensive and intensive system were found to be 31.14±0.13,Reproductive performance: At the end of hatching 29.37±0.15and 9.04±0.16respectively.The mean process, egg were classified as infertile, hatched, percentage of infertile eggs were differ significantly embryonic mortalities (early and late) and dead in (P>0.01).The highest infertile eggs were found in shell.Hatched poults were collected, counted and turkeys reared in free range system followed by semi weighed by using an electronic balance.Reproductive intensive system and intensive system of management.ratio with increasing egg size making the gas heat Mroz et al., (2010) reported that the number of exchange more difficult.Low fertility values have also infertile eggs is low in turkeys, but it may reach 10% at been reported in traditional chicken rearing (Hocking et al., 2007).the beginning and towards the end of the laying This can be explained by poor management season.The mean ± SE percentages of early and late embryonic mortalities in the free range, semi intensive practices, mating behavior or reproductive physiology and intensive system were found to be 6.63±0.07 and in flocks often maintained in small groups.A number

Table - 1. Effect of rearing system reproductive traits of turkeys (Mean ± SE)
P<0.01; NS-non significant.Means bearing same superscripts row-wise do not differ significantly. *