Ishaq et al., The J. Anim. Plant Sci. 28 (4) 2018 965 HATCHING PERFORMANCE OF ARBOR ACRES BROILER BREEDER STRAIN AT FOUR PRODUCTION PHASES WITH THREE EGG WEIGHTS AND STORAGE PERIODS H. M. Ishaq 1 , M. Akram 1 , M. E. Baber 2 , A. W. Sahota 1 , A. S. Jatoi 3† , R. Yousaf 1 , F. Hussnain 1 and R. Naeem 1 1 Department of Poultry Production, Faculty of Animal Production and Technology, University of Veterinary and Animal Sciences, Lahore, Pakistan; 2 Vitual University, Pakistan; 3 Department of Poultry Husbandry, Faculty of Animal Production and Technology, University of Veterinary and Animal Sciences, Sakrand, Pakistan 3† Corresponding Author’s E-mail: asultanjatoi@sbbuvas.edu.pk ABSTRACT The present study was conducted to evaluate the hatching performance (average egg size, moisture loss, fertility, hatchability and hatch of fertile eggs) in Arbor Acre broiler breeder strain eggs during four production phases (pre-peak, 25-28; peak, 29-36; post-peak, 37-52 and terminal, 53-56 th weeks of age), categorized into three egg weights (small, medium and large; changed in each production phase), maintained at three different storage periods (1, 4 and 7- days) and replicated 6 times. A total of 93312 fertile eggs (pre-peak: 11664, peak: 23328, post-peak: 46656 and terminal: 11664) in 4 production phases were subjected to hatching in a commercial hatchery. The data were analyzed using ANOVA technique under randomized complete block design in a 4×3×3 factorial arrangement and means were compared using DMR Test. Results showed significant (p≤0.05) differences for average egg size and fertility percent in large egg weight category alone as well as its interaction with all three storage periods. Significantly (p≤0.05) higher moisture loss was observed in large and small egg categories and highest in seven days storage alone and its interaction with all egg weight categories during post-peak. Regarding hatching traits, significantly (P≤0.05) highest hatchability percent and hatch of fertile percent were observed in large egg weight category alone and in interaction between egg weight categories and storage periods during pre-peak and peak, while during post-peak and terminal phases medium egg weight category showed higher hatchability and hatch of fertile percent. Significantly (p≤0.05) higher hatchability and hatch of fertile percent were observed in one and four day storage period. It is concluded from the present study that large egg weight category coupled with 1 or 4 day storage period had maximum fertility, hatchability and hatch of fertile percent in Arbor Acre broiler breeder strain. Key words: Broiler breeder strain, egg size, fertility and hatchability percent, hatch of fertile, production phases. INTRODUCTION The modernization of incubation technology and genetic selection for improved growth performance has decreased the production cycle time in broiler chickens and the incubation process of 3 weeks has respectively become a larger part of the total chicken lifespan (Hulet, 2007). Due to growing global population, entire pressure to fulfill dietary needs is on the commercial broiler industry to produce more chicks and hence the meat. Commercial broiler is being raised with full genetic potential and nutritional control. Now, the major focus of broiler producers is to control the losses in poultry production chain. More number of chicks can be obtained by managing the hatching eggs and incubation parameters which are crucial to incubation and hatching process. Egg weight and its storage period are among the most critical post-ovipositional parameters affecting the embryonic development and hatching of day old chicks (Alsobayel et al., 2013; Abudabos et al., 2017) as well as the subsequent performance (Sözcü and Ipek, 2017). Egg weight is related to egg weight loss due to water evaporation during incubation (Stępińska et al., 2017). A positive relationship between egg weight loss and egg weight may result in decreased hatchability and higher early and late embryonic mortality (Alabi et al., 2012) whereas some studies showed inverse relationship between egg weight and egg weight loss (Abanikannda et al., 2011). However, Abiola et al. (2008) were unable establish a particular trend for weight loss in varying egg sizes. Hatchiblity of incubated eggs was higher in heavy eggs than the light weight eggs (Prabkaran et al., 1984; Senapati et al., 1996). Asuquo and Okon (1993) observed that egg size within the intermediate range of 45-56 g would hatch better than small eggs. On the other hand, Proudfoot and Hulan (1981) found that the weight of egg had no effect on fertility and hatchability of fertile eggs. However, Abiola et al. (2008) reported that hatchability did not follow any particular trend with egg weight. Although several other factors are involved in fluctuating the hatching traits, but the length of egg storage period before the incubation is of particular importance due to its influence on physio-chemical properties of egg (Alsobayel The Journal of Animal & Plant Sciences, 28(4): 2018, Page: 965-972 ISSN: 1018-7081