title: Threonine requirement of White Pekin ducks from hatch to 21 d of age.
abstract: 1. A dose-response experiment with 5 dietary threonine concentrations (5.0, 5.8, 6.6, 7.4 and 8.2 g/kg) was conducted to estimate the threonine requirement of White Pekin ducks from hatch to 21 d of age. 2. A total of 240 one-d-old male White Pekin ducks were allotted to 5 experimental treatments and each treatment contained 6 replicate pens with 8 ducks per pen. Ducks were reared in raised wire-floor pens from hatch to 21 d of age. At 21 d of age, growth performance and intestinal morphology were determined. 3. The weight gain and feed intake of Pekin ducks increased and feed/gain of these birds decreased linearly or quadratically as dietary threonine increased from 5.0 to 8.2 g threonine/kg. Compared to ducks fed on diets containing 5.0 g threonine/kg, ducks given diets containing 7.4 g threonine/kg had higher villus height in duodenum, jejunum and ileum. 4. The threonine requirements for weight gain of White Pekin ducks from hatch to 21 d of age was estimated to be 6.72 g/kg when dietary crude protein concentration was 189.8 g/kg and threonine supply was critical for maintaining intestinal structure of these birds.
authors.affiliation: a Institute of Animal Sciences , Chinese Academy of Agricultural Sciences , Beijing 100193 , China.
authors.forename: M
authors.initials: M
authors.lastname: Xie
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: Z G
authors.initials: ZG
authors.lastname: Wen
authors.forename: J
authors.initials: J
authors.lastname: Tang
authors.forename: W
authors.initials: W
authors.lastname: Huang
authors.forename: S S
authors.initials: SS
authors.lastname: Hou
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena / Q000187:drug effects; D000818:Animals; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D004372:Ducks / Q000254:growth & development* / Q000378:metabolism*; D008297:Male; D013912:Threonine / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D015430:Weight Gain / Q000187:drug effects
chemical_list: D013912:Threonine