De Heus Animal Nutrition B.V., 6717 VE Ede, the Netherlands; Animal Nutrition Group, Department of Animal Sciences, Wageningen University, NL-6700 AH Wageningen, the Netherlands; Adaptation Physiology Group, Department of Animal Sciences, Wageningen University, NL-6700 AH Wageningen, the Netherlands.
De Heus Animal Nutrition B.V., 6717 VE Ede, the Netherlands.
Poult Sci. 2023 Feb;102(2):102410. doi: 10.1016/j.psj.2022.102410. Epub 2022 Dec 9.
Body composition plays an important role in reproduction in broiler breeders. The aim of this study was to evaluate the dynamics in body composition and energetic efficiency in broiler breeders, using different dietary strategies. About 1,536-day-old pullets were randomly allotted to 24 pens in a 2 × 4 factorial design with 2 growth curves (standard or elevated (+15%)) and 4 diets, with a step-wise increment in energy (96, 100, 104, and 108% apparent metabolizable energy nitrogen corrected [AME]) fed on a pair-gain basis. Body composition was determined at 10 time points from 0 to 60 wk of age. Body protein mass was linearly related to body weight (BW) in growing breeders, which can be expressed as -6.4+0.184BW (R = 0.99; P < 0.001). Body fat mass was exponentially related to BW in growing breeders, which can be expressed as -42.2+50.81.0006 (R = 0.98; P < 0.001). A higher energy-to-protein ratio resulted in higher body fat mass at the same BW (P < 0.001). Sexual maturation was related to body protein mass at 21 wk of age, where each 100 g of body protein mass extra advanced sexual maturation by 5.4 d (R = 0.83). Estimates of energetic efficiency for growth (k) and egg production (k) appeared not constant, but varied with age in a quadratic manner between 0.27 and 0.54 for k and between 0.28 and 0.56 for k. The quadratic relationship could be expressed as k=0.408-0.0319Age+0.00181Age (R = 0.72; P < 0.001) and k=-0.211+0.034Age-0.00042Age (R = 0.46; P < 0.001). Body protein mass in broiler breeders is tightly regulated and mainly depended on BW and seems to be the main determinant for sexual maturation. Body fat mass is exponentially related to BW, where an increase in dietary energy-to-protein ratio results in a higher body fat mass. Treatments had minimal effects on estimated energetic efficiencies in breeders.
机体成分在肉种鸡的繁殖性能中起着重要作用。本研究旨在评估不同饲粮策略对肉种鸡机体成分和能量利用效率的动态影响。选用 1536 日龄的母鸡，采用 2×4 析因设计，设 2 个生长曲线（标准或提高（+15%））和 4 种饲粮，在等增重基础上，饲粮能量逐步递增（96、100、104 和 108%表观代谢能氮校正值[AME]）。从 0 至 60 周龄，在 10 个时间点测定机体成分。生长阶段的母鸡，体蛋白质量与体重（BW）呈线性关系，可表示为-6.4+0.184BW（R2=0.99；P＜0.001）。生长阶段的母鸡体脂肪质量与 BW 呈指数关系，可表示为-42.2+50.81.0006（R2=0.98；P＜0.001）。较高的能氮比在相同 BW 时导致体脂肪质量更高（P＜0.001）。21 周龄时，性成熟与体蛋白质量相关，每增加 100 g 体蛋白质量，性成熟提前 5.4 d（R2=0.83）。生长（k）和产蛋（k）的能量利用效率估计值似乎不是常数，而是以二次方式随年龄变化，0.27 至 0.54 为 k，0.28 至 0.56 为 k。二次关系可表示为 k=0.408-0.0319Age+0.00181Age（R2=0.72；P＜0.001）和 k=-0.211+0.034Age-0.00042Age（R2=0.46；P＜0.001）。肉种鸡的体蛋白质量受到严格调控，主要取决于 BW，似乎是性成熟的主要决定因素。体脂肪质量与 BW 呈指数关系，饲粮能氮比的增加导致体脂肪质量增加。处理对种鸡的能量利用效率估计值影响很小。
