Effects of dietary crude protein on the growth performance, carcass characteristics and serum biochemical indexes of Lueyang black-boned chickens from seven to twelve weeks of age

Sk Liu,Zp Wang,Yn Min,Zy Niu,J Zhang,Fz Liu,Tt Sun,Zf He,Hl Li

doi:10.1590/1516-635x1701103-108

Abstract

This study was undertaken to assess dietary crude protein (CP) concentration for optimum growth performance and carcass characteristics of Lueyang black-boned chicken. In total, six hundred 42-day-old Lueyang black-boned chicks were randomly assigned to five treatments, each with six replicate pens with ten males and ten females. The birds fed experimental diets with different levels of protein concentration of 120, 140, 160, 180 and 200 g kg-1 from seven to twelve weeks of age respectively. On day of 84, weight gain, feed intake, and feed:gain ratio were measured, and two chickens (one male and one female) close to the average weight of all birds in each treatment were selected from each pen and sacrificed to evaluate carcass traits and selected serum biochemical indexes. Dietary CP concentration did not have any significant influence on feed intake (p>0.05). The birds fed the diet with 180 or 160 g kg-1 CP concentration exhibited greater (p<0.05) growth rate, better feed conversion ratio, relative breast weight and albumin concentration in serum than that of those fed other dietary CP concentrations. According to the results of regression analysis, the CP requirements of Lueyang black-boned chicken from seven to twelve weeks of age for optimal weight gain and feed:gain ratio were 174 and 170 g kg-1, respectively.

Highlights

Black-boned chicken, called “Wuguji’’ in Chinese, is a kind of unique in indigenous fowl breeds in China
It was clear that dietary crude protein (CP) did not have any significant influence on feed intake (p>0.05)
The body weight of chickens fed the diet with 180 g kg-1 CP was significantly higher (p

Summary

Introduction

Black-boned chicken, called “Wuguji’’ in Chinese, is a kind of unique in indigenous fowl breeds in China They can be distinguished from other chickens. The origin of Lueyang black-boned chickens is the Shaanxi province of China This breed is characterized by black-colored comb, beak, tongue, legs, toes, and skin. To their higher income and focused on healthy foods, more and more people have accepted and enjoyed this bird’s meat in China. Such preference of consumers has strongly promoted the production of Chinese black-boned chickens. The knowledge on the nutritional physiology and how nutrients regulate growing, development, and live performance in Lueyang black-boned chicken is still lacking

Methods

Results

Conclusion