title: Effect of feeding different dietary levels of energy and protein on growth performance and immune status of Vanaraja chicken in the tropic.
abstract: OBJECTIVE
  The present study was conducted to observe the effect of feeding dietary level of energy and protein on growth performance and immune status of Vanaraja chicken in the tropic.
  
  
  METHODS
  The experiment was conducted for 56 days on 540 1-day-old chicks, which were individually weighed and distributed into nine groups having 60 birds in each. Each group was further subdivided into triplicates having 20 birds in each. Nine different experimental rations were formulated with three levels of protein, viz., 17%, 19%, and 21%; each with three levels of energy (2600, 2800, and 3000 kcal metabolizable energy [ME]/kg), respectively. Group T8 serves as control fed with 21% protein and 2800 kcal energy as per Project Directorate of Poultry, Hyderabad given requirement. Feed consumption, live weight gain, body weight change, and feed conversion ratio (FCR) were calculated based on the amount of feed consumed every week. All the birds were vaccinated following standard protocol. The hemagglutination inhibition (HI) test have been performed to assess the immunity potential of birds due to dietary effect, and serum samples were subjected to HI test at 7, 14, 21, and 28 days of age. Finally, economics of broiler production was calculated on the cost of feed per kg live weight gain.
  
  
  RESULTS
  This study revealed that the effect of feeding different levels of energy and protein on growth parameters such as body weight gain and FCR was found to be significantly higher (p<0.05) containing 19% and 21% crude protein with 3000 kcal ME/kg in Vanaraja birds. There was a gradual increase in antibody titer against New castle disease virus as the level of protein and energy increase. It is speculated that the better body weight gain corroborate health and antibody titer. Moreover, the better immune response recorded in the study might be due to better nutrient utilization and its extension toward the better immune response. Higher energy with medium protein diet positively reflects to obtain desirable performance economically.
  
  
  CONCLUSIONS
  It was positive inclination toward ration containing high protein and energy which influence the immune response of Vanaraja birds to obtained desirable performance economically also.
authors.affiliation: Department of Animal Nutrition, Bihar Veterinary College, Bihar Agricultural University, Patna, Bihar, India.
authors.forename: Shahla
authors.initials: S
authors.lastname: Perween
authors.affiliation: Department of Animal Nutrition, Bihar Veterinary College, Bihar Agricultural University, Patna, Bihar, India.
authors.forename: Kaushalendra
authors.initials: K
authors.lastname: Kumar
authors.affiliation: Department of Animal Nutrition, Bihar Veterinary College, Bihar Agricultural University, Patna, Bihar, India.
authors.lastname: Chandramoni
authors.affiliation: Department of Animal Nutrition, Bihar Veterinary College, Bihar Agricultural University, Patna, Bihar, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Animal Nutrition, Bihar Veterinary College, Bihar Agricultural University, Patna, Bihar, India.
authors.forename: Pankaj Kumar
authors.initials: PK
authors.lastname: Singh
authors.affiliation: Department of Veterinary Microbiology, Bihar Veterinary College, Bihar Agricultural University, Patna, Bihar, India.
authors.forename: Manoj
authors.initials: M
authors.lastname: Kumar
authors.affiliation: Division of Animal Science, ICAR- Research Complex for Eastern Region, Patna, Bihar, India.
authors.forename: Amitava
authors.initials: A
authors.lastname: Dey
keywords: Vanaraja; body weight gain; economics; energy; immunity; protein