Evaluation of Dietary Energy and Protein Requirements of an Improved Backyard Chicken Variety (Rajasri) in its Juvenile Phase

A study was conducted to evaluate the dietary energy and protein requirements of an improved backyard chicken variety (Rajasri) during its juvenile phase (0–8 weeks of age). Day old Rajasri chicks (n=360) were randomly distributed into 9 groups of 5 replicates with 8 chicks per replicate. They were fed diets with three ME levels (2400 kcal, 2600 kcal and 2800 kcal ME/kg) and three CP levels (16, 18 and 20%) in a 3 × 3 factorial design. The body weight gain of chicks fed 2600 and 2800 kcal ME/kg diets was higher (P<0.05) than those fed 2400 kcal ME/kg and increased (P<0.001) with increasing levels of CP in diet. Feed intake was higher (P<0.05) in groups fed 2400 and 2600 kcal ME/kg when compared to 2800 kcal ME/kg fed groups and was not influenced by different levels of CP in the diet. Feed conversion ratio of groups fed 2600 and 2800 kcal ME/kg was better than those fed 2400 kcal ME/kg and improved with increasing levels of CP. Protein retention was better (P<0.05) in groups fed diets having 2600 and 2800 kcal ME/kg and was not influenced by different CP levels or ME and CP interactions. Energy retention was similar in different groups. Serum total cholesterol level was higher (P<0.001) in chicks fed diets containing 2400 kcal ME/kg and serum total protein level was similar and not influenced by different levels of ME, CP and their interactions. Hence, provision of diet containing 2600 kcal ME/kg and 20% CP would be ideal for eliciting optimum growth in Rajasri chicks during juvenile phase.