AGRICULTURAL RESEARCH COMMUNICATION CENTRE www.arccjournals.com/www.ijaronline.in *Corresponding author’s e-mail: drmanas01@gmail.com 1 Animal Reproduction Division, Indian Veterinary Research Institute, Izatnagar-243 122, U.P., India. 2 UBKV, Pundibari, Coochbehar-736165, West Bengal, India. 3 NRC on Pig, Rani, Guwahati, Assam, India. 4 Department of Gynaecology, WB University of Animal and Fishery Science, K.B. Sarani, Kolkata- 37, West Bengal, India. 5 Agricultural Technology Application Research Institute, Umroi Road, Umiam-793103, Meghalaya, India. Indian J. Anim. Res., 52 (7) 2018 : 1071-1076 Print ISSN:0367-6722 / Online ISSN:0976-0555 Effect of season on growth and reproduction performance of improved backyard poultry in North Eastern Hill Region Manas Kumar Patra 1* , D.K. Hajra 2 , R.K. Das 3 , Pradip Sarkar 4 and Bidyut C. Deka 5 ICAR Research Complex for NEH Region, Nagaland Centre, Jharnapani, Medziphema-797 106, Nagaland, India. Received: 22-04-2016 Accepted: 09-03-2017 DOI: 10.18805/ijar.v0iOF.9122 ABSTRACT A study was undertaken to evaluate the seasonal influence on performance of Vanaraja (n=3924) and Gramapriya (n=2227) maintained in five different batches during 2011-14. Better growth was observed in summer during brooding. At brooding, mortality was significantly higher during winter in Vanaraja and during summer in Gramapriya. The egg production was higher when birds started laying in winter than in summer. The overall Hen Day Egg Production (HDEP) was higher in Vanaraja (p<0.01) than the Gramapriya. The fertility level varied between 68 to 90% in both varieties. The hatchability percentage on fertile egg set (FES) varied within the range of 70 to 90. It was concluded that better egg production performance could be obtained from Vanaraja birds, raised in summer and those initiated laying in winter. Therefore, the seasonal factors should be taken care of while raising parent line to achieve optimum production. Key words: Egg production, Growth, Gramapriya, Season, Vanaraja. INTRODUCTION Rural poultry sector contributes nearly 30 per cent of total egg production besides providing nutritional supplement (DAHD, 2011). Backyard poultry farming; a low input or no input venture in India (Ahlawat, 2013) needs to be strengthened to keep pace with consumer demand for colored birds and brown-shelled eggs (Dolberg, 2004). The Vanaraja and Gramapriya birds were introduced in backyard farming with the aim of increasing quality meat and egg production. In many parts of the country, these two varieties have been popularized. Supply of quality germplasm in the backyard venture is one of the key issues in India. Perhaps, this is more challenging in the North-eastern part of our country for its geo-climatic situation apart from other intrinsic constrains. Since, local agro-climatic condition seemed to influence the egg production and its fertility (Alem, 2014), the influence of local climatic condition on performance of the parent line is necessary to provide better consultancy to the farmers and extension workers. In this connection, a study was undertaken to assess the performance of parent line with the following objectives viz., 1. to study the seasonal influence on growth and mortality during brooding and growing phases, 2. to study the reproductive performance of female in a complete laying cycle 3. to evaluate the egg production pattern in different phases of laying cycle of birds raised in two distinct weather patterns during summer and winter. MATERIALS AND METHODS Study location and birds: The experiment was conducted on parent line of Vanaraja (n=3924) and Gramapriya (n=2227) chicken varieties procured at day old from the Directorate of Poultry Research (DPR), Hyderabad, reared in the deep litter system at the experimental shed of ICAR Research Complex for NEH Region, Nagaland Centre, Jharnapani, Nagaland, India. Weather pattern: ICAR Research Complex for NEH Region, Nagaland Centre is situated at the latitude of 25°45’24"N, longitude of 93°50’26"E, and at altitude of 281m msl. According to the agromet observatory and automatic weather station of the institute the mean monthly maximum and minimum air temperatures were found to vary from 19.3 to 36.5°C and 5.1 to 26.3°C, respectively. Average maximum and minimum relative humidity varied from 56% (January) to 90% (August) and 3% (February) to 84% (August). The normal rainfall in the region varied from 1350 to 1600 mm with maximum rainfall during April to July and almost no rainfall during November to February (Annual Report, ICAR RC for NEH region, 2012-13). Growth and mortality of parent stock: The male and female parents were reared in separate compartment. The