title: Effects of a multi-enzyme complex on growth performance, nutrient utilization and bone mineralization of meat duck.
abstract: BACKGROUND
  Previous studies with broiler have shown dietary supplementation with multi-enzyme complex containing non-starch polysaccharides (NSP) degrading enzymes and phytase is efficient in releasing phosphorus (P), calcium (Ca), energy and amino acids from corn-soybean meal diets or corn-sorghum diets, hence compensating considerable levels of nutrients in formulation. Notwithstanding, such potentials have not been well defined in duck nutrition. Giving China being the largest duck producing country, we conducted this study to establish adequate specifications of major nutrients along with multi-enzyme complex to meat duck from day-old to slaughter, focusing on performance, utilization of nutrients and bone mineralization. Five dietary treatments were: Positive control (PC,T1 ): the nutrients concentration of diet for 1 to 14 d of age were apparent metabolizable energy(AME) 2,800 kcal/kg, crude protein (CP)19.39%, Ca 0.85%, available phosphorus (avP) 0.42%; for 15 to 35 d of age these parameters were AME 2,900 kcal/kg, CP 16.47%,Ca 0.76%,avP 0.38%; Negative control 1(NC1,T2), the AME and digestible amino acids (DAA) were reduced by 70 kcal/kg and 2.0%, avP and Ca by 1.0 g/kg from PC diet; Negative control 2( NC2,T4), the down-spec from PC diet was AME 100 kcal/kg, DAA 2.5%, avP 1.5 g/kg and Ca 1.2 g/kg; The enzyme complex was added at the same dosage (200 mL/ 1,000 kg) on NC1 (T3) and NC2 (T5) diets.
  
  
  RESULTS
  Comparing with the ducks fed on T1, T3 and T5 diets, the birds fed on NC2 diet showed the lowest (P < 0.05) body weight ( d 14 and 35), feed intake (d 35), tibia ash, Ca and P contents (d 14 and 35), and the utilization of nutrients (P < 0.05). The supplementation with the enzyme complex to the NC diets restored growth rate, utilization of nutrients and bone mineralization to the level of the PC diet, and increased AME by 60 kcal/kg and 117 kcal/kg, respectively for the NC1 and NC2 diets.
  
  
  CONCLUSIONS
  These results suggest that down-spec AME by 100 kcal/kg, DAA by 2.5%, avP by 1.5 g/kg and Ca by 1.2 g/kg caused detrimental effects on duck performance compared with those fed on the PC diet, and these performance losses can be compensated by the addition of the multiple-enzyme complex.
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Qiufeng
authors.initials: Q
authors.lastname: Zeng
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Yuheng
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Ding
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Shiping
authors.initials: S
authors.lastname: Bai
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Xuan
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Zhuowei
authors.initials: Z
authors.lastname: Su
authors.affiliation: Adisseo Asia Pacific Pte Ltd, Singapore, 179360 Singapore.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Sichuan Ya'an, 625014 China.
authors.forename: Keying
authors.initials: K
authors.lastname: Zhang
keywords: Formulation specification; Growth; Meat duck; Non-starch polysaccharides enzyme; Phytase