EFFECT OF DIETARY-PROTEIN CONTENT ON LIVE AND CARCASS PERFORMANCE OF HETEROZYGOUS NAKED NECK AND NORMALLY FEATHERED BROILERS

1. An experiment was conducted to determine the effect of different di etary protein contents on the performance of naked neck (Na/na) and no rmally feathered (na/na) broilers. 2. Chicks from the two genotypes we re reared in wire-floored cages and divided at random into 3 groups. B irds were fed on high protein (HP, 12.99 MJ ME, 238 g crude protein/kg and 12.94 MJ ME, 216 g crude protein/kg from 0 to 3 and 3 to 7 weeks, respectively), medium protein (MP, 12.99 MJ ME, 219 g crude protein/k g and 12.87 MJ ME, 201 g crude protein/kg from 0 to 3 and 3 to 7 weeks ), and low protein (LP, 12.94 MJ ME, 205 g crude protein/kg and 12.75 MJ ME, 184 g protein/kg from 0 to 3 and 3 to 7 weeks) diets. 3. The LP diets resulted in a significantly lower daily body weight gain of mal es from 0 to 3 weeks. Dietary protein content had no effect on body we ight gain from 3 to 7 weeks, body weight at 7 weeks, and the food inta ke of birds. Carcase composition of birds from both genotypes was unaf fected by dietary protein. 4. Naked neck birds had significantly highe r body weights at 7 weeks. Yields of carcase and breast of Na/na males were significantly higher than those of na/na males. There were no si gnificant differences between females from the two genotypes as regard s carcase yield. 5. It was concluded that the dietary protein requirem ents of naked neck birds were similar to those for normally feathered birds.