McLeod E S, Jalal M A, Zuidhof M J
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada T6G 2P5.
Department of Animal Production, Faculty of Agriculture, University of Jordan, Amman, 11942, Jordan.
Poult Sci. 2014 Nov;93(11):2932-40. doi: 10.3382/ps.2014-04235. Epub 2014 Sep 11.
Approximately 84% of the energy in chicken eggs resides in the yolk. A robust model of ovarian follicle development is therefore valuable for estimating energy requirements of laying hens. The current experiment was designed to model the growth of ovarian follicles in 32-wk-old modern commercial line (CL) and unselected heritage line (HL) Single Comb White Leghorn hens. The volume of yolk deposited daily during the rapid growth phase (RGP) was estimated using a double dye technique. For 21 d, 8 CL and 8 HL hens were fed capsules (no. 1) containing Sudan IV (red) and Sudan Black dyes on alternate days. An additional 8 control CL hens were fed empty capsules. Eggs were collected, and the daily volume of yolk deposited was estimated. Significant differences are reported where P < 0.05. Dye had no significant effect on BW, ME intake, or egg weight. Maintenance ME requirements were 192 and 177 kcal/kg(0.67) for CL and HL hens, respectively. Duration of the RGP was shorter (7.35 d) in the CL hens compared with the HL hens (7.95 d). A nonlinear Lomolino model described follicular weight, which varied between strains over d 2 to 9 of follicle development; at each day during development, follicle weights were higher where RGP were shorter. The volume of yolk deposited for the 8 d preceding oviposition in CL was 0.17, 0.28, 0.43, 0.99, 1.84, 2.47, 2.82, 2.86, and 2.51 cm(3); and in HL was 0.17, 0.33, 0.72, 1.40, 2.15, 2.46, 2.48, 2.32, and 1.93 cm(3). The HL had a higher rate of yolk deposition 7 to 5 d before oviposition, and CL had a higher rate of yolk deposition 3 to 1 d before oviposition with no significant difference between lines on d 4 before oviposition. Although growth patterns differed, there were no differences among lines in final follicle weights (14.1 g) or retained energy (42.4 kcal).
鸡蛋中约84%的能量存在于蛋黄中。因此，一个强大的卵泡发育模型对于估计蛋鸡的能量需求很有价值。当前的实验旨在模拟32周龄现代商业品系（CL）和未经选择的传统品系（HL）单冠白来航蛋鸡卵泡的生长情况。在快速生长阶段（RGP），使用双重染色技术估计每日沉积的蛋黄体积。在21天内，8只CL蛋鸡和8只HL蛋鸡每隔一天喂食含有苏丹IV（红色）和苏丹黑染料的胶囊（1号）。另外8只CL对照蛋鸡喂食空胶囊。收集鸡蛋，并估计每日蛋黄沉积量。当P < 0.05时报告显著差异。染料对体重、代谢能摄入量或蛋重没有显著影响。CL和HL蛋鸡的维持代谢能需求分别为192和177千卡/千克（0.67）。CL蛋鸡的RGP持续时间（7.35天）比HL蛋鸡（7.95天）短。一个非线性洛莫利诺模型描述了卵泡重量，在卵泡发育的第2至9天，不同品系之间卵泡重量有所不同；在发育的每一天，RGP较短的地方卵泡重量更高。CL蛋鸡在排卵前8天沉积的蛋黄体积分别为0.17、0.28、0.43、0.99、1.84、2.47、2.82、2.86和2.51立方厘米；HL蛋鸡分别为0.17、0.33、0.72、1.40、2.15、2.46、2.48、2.32和1.93立方厘米。HL蛋鸡在排卵前7至5天的蛋黄沉积速率较高，CL蛋鸡在排卵前3至1天的蛋黄沉积速率较高，排卵前第4天品系间无显著差异。尽管生长模式不同，但品系间最终卵泡重量（14.1克）或保留能量（42.4千卡）没有差异。
