title: Effects of high peanut meal with different crude protein level supplemented with amino acids on performance, carcass traits and nitrogen retention of Chinese Yellow broilers.
abstract: This study assessed the effects of feeding high peanut meal diets of reduced crude protein (CP) content supplemented with essential amino acids (EAA) on growth performance, carcass traits, biochemical indices in plasma, and nitrogen (N) retention of male and female Lingnan Yellow broilers from day 22 to day 42 of age. Each of four dietary treatments (19%, 18%, 17% or 16% CP, dietary CP level reduced by the reduced dietary peanut meal) contained six replicate pens with 35 birds of each sex (males and females with equal number), separately (1680 in total). The three diets with reduced CP were supplemented with 5 EAA to meet the requirements and provide the same levels as in the 19% CP diet. Average daily gain decreased and feed:gain ratio was worse in both sexes with reduced CP% (linear, p < 0.05). Dressing percentage increased as CP% decreased in males (linear, p < 0.05) and thigh muscle percentage reduced slightly in females (linear, p < 0.05). Abdominal fat percentage of males fed the 17% CP was the lowest (quadratic, p < 0.05). The plasma metabolic indices, concentrations of triglycerides and malondialdehyde, showed linear responses to reduced CP% (p < 0.05) with triglycerides increasing while malondialdehyde decreased. Plasma uric acid increased in females (linear, p < 0.05), but not in males, as CP% decreased. Efficiency of N retention increased and N excretion strikingly decreased with lower CP diets (p < 0.001), and both variables showed significant (p < 0.05) linear and quadratic effects. It is concluded that there was a limit to which dietary CP of broilers could be reduced without adverse effects. Dietary CP could be reduced to 17% for males and 18% for females (or 18% when fed together) between day 22 and day 42, if diets are supplemented with synthetic EAA.
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Gou
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: S Q
authors.initials: SQ
authors.lastname: Jiang
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Jiang
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: C T
authors.initials: CT
authors.lastname: Zheng
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: L
authors.initials: L
authors.lastname: Li
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: D
authors.initials: D
authors.lastname: Ruan
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: F
authors.initials: F
authors.lastname: Chen
authors.affiliation: Institute of Animal Science, Guangdong Academy of Agricultural Sciences, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
authors.forename: X J
authors.initials: XJ
authors.lastname: Lin
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage / Q000494:pharmacology*; D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D010367:Arachis / Q000737:chemistry*; D001823:Body Composition; D002645:Chickens / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D008297:Male; D009584:Nitrogen / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D004044:Dietary Proteins; D009584:Nitrogen
keywords: Chinese Yellow broiler; amino acid supplementation; growth performance; low-protein diet; nitrogen retention