Animal Production Research Advances, 4(1): 19-25, 2008 ra p a / journals / org . tapasinstitute . www © Tapas Institute of Scientific Research and Development, 2008 19 RESPONSES OF NEW ZEALAND WHI TE AND CALI FORNI AN RABBI T DOES TO DI FFERENT DI ETARY PROTEI N LEVELS UNDER EGYPTI AN CONDI TI ONS U. M. Abdel-Monem 1 , Kh. M. Mahrose 2 and M. S. Darwish 3 1 Department of Animal Production, Faculty of Agriculture, Zagazig University, Egypt 2 Department of Poultry Science, Faculty of Agriculture, Zagazig University, Egypt 3 Animal Production Research Institute, Dokki, Cairo, Egypt Corresponding author: Dr. U. M. Abdel-Monem; E-mail; Ormamohamed_2010@yahoo.com ABSTRACT Seventy two does of New Zealand White rabbits (NZW) and Californian (Cal) at six months of age were used in a 2 ×2 ×3 factorial design experiment to study the effects of dietary protein levels (16, 18 as control level and 20%) on performance of NZW and Cal doe rabbits under hot (from May to September) and mild (from October to April) environmental conditions. The does reared under hot conditions consumed significantly (p<0.05 or 0.01) less feed and more water in comparison with those reared under mild conditions. Feed intake was insignificantly affected by breed and dietary protein levels. Rectal temperature and respiratory rate significantly (p<0.05) improved during the mild environmental conditions. Gestation period significantly (p<0.05) varied according to the environmental conditions, but was not significantly affected by breeds, dietary protein levels and by their interaction. Litter size, litter weight (gm) and bunny weight (gm) at the different ages studied were significantly (p<0.05 and 0.01) higher during the mild conditions than the hot one and also in does fed ration containing 20% crude protein (CP) across the different ages studied. Does fed diets containing 20% CP had significantly (p<0.05 and 0.01) higher litter size, litter weight, bunny weight and bunny weight gain across all the ages studied. Total protein, albumin, globulin, total lipids, T 3 and T 4 were not significantly affected by any of the environmental conditions, breeds, dietary protein levels or their interactions. Keywords: Rabbit, environmental condition, dietary protein, Egypt I NTRODUCTI ON There is no doubt that rabbit farming has significant potential and useful contribution in improving meat supply and food security in developing countries. Although there is an increasing interest in the enterprise of raising rabbits of different sizes in Egypt, several difficulties constrain the success of these enterprises (Abdel-Monem et al., 2007). Heat stress is one of the most serious problems facing rabbit production in Egypt. It influences animal welfare, performance, yield and quality of products (El-Maghawry, 1990; Abdel-Monem, 1995; Ayyat and Marai, 1998; Barakat, 2001; Azoz and El-Kholy, 2006; El-aaser, 2007). Restriction of feeding time to 12 hours per day during night (nocturnal feeding) decreased the sever effects of heat stress and improved the productive and reproductive performance of rabbits during summer season (Mahrose, 2000). Seventy two does of New Zealand White (NZW) and Californian rabbits aged 6 months were used during the present study to investigate the effects of dietary protein feeding on doe rabbit's performance and their weanlings under different environmental conditions (hot and mild seasons) 9n Egypt. MATERI ALS AND METHODS The present work was carried out at a commercial farm in Zagazig area, Sharkia Governorate, Egypt. Seventy two does of New Zealand White rabbits (NZW) and Californian (Cal) at six months of age were used in a 2 ×2 ×3 factorial design experiment to study the effects of dietary protein levels (16, 18 as control level and 20%) on performance of NZW and Cal doe rabbits under hot (from May to September) and mild (from October to April) environmental conditions. Doe rabbits were randomly distributed into two experimental groups (36 does in each environmental condition) of nearly equal average body weight. Each experimental group was subdivided into two breeds (18