title: Net Phosphorus Requirements of Dorper×Thin-tailed Han Crossbred Ram Lambs.
abstract: A comparative slaughter trial was conducted to estimate the phosphorus (P) requirement for maintenance and growth of crossbred lambs of Dorper with a Chinese indigenous sheep breed, thin-tailed Han sheep. Thirty-five Dorper×thin-tailed Han crossbred, noncastrated ram lambs (20.3±0.22 kg of shrunk body weight (SBW)) were used. Seven lambs were randomly chosen and slaughtered at 20 kg SBW as the baseline group for measuring initial body composition. Another seven lambs were also randomly chosen and offered a pelleted mixed diet for ad libitum intake and slaughtered at 28 kg SBW. The remaining 21 sheep were randomly divided into 3 groups with 7 sheep each and subject to the same diet of either 70 or 40% of ad libitum intake. The 3 groups were slaughtered when the sheep fed ad libitum reached 35 kg of SBW. Body P contents were determined after slaughter. The results showed that the net P requirement for maintenance was 30.0 mg/kg of empty body weight (EBW) or 23.4 mg/kg body weight (BW), and the P requirement for growth decreased from 5.3 to 5.0 g/kg of EBW gain as the lamb grew from 20 to 35 kg. The net P requirement for growth of Dorper×thin-tailed Han crossbred ram lambs was lower than that of sheep adopted by the American nutritional system.
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Shoukun
authors: S
authors: Ji
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Guishan
authors: G
authors: Xu
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Chenggang
authors: C
authors: Jiang
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Kaidong
authors: K
authors: Deng
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Yan
authors: Y
authors: Tu
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Naifeng
authors: N
authors: Zhang
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Tao
authors: T
authors: Ma
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Can
authors: C
authors: Lou
authors: Institute of Feed Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors: Qiyu
authors: Q
authors: Diao
keywords: Comparative Slaughter Trial; Growth; Lambs; Maintenance; P Requirement