Department of Animal Science, Faculty of Agriculture, Ankara University, Ankara 06110, Turkey.
Petersime nv, Zulte (Olsene), 9870, Belgium.
Poult Sci. 2020 Dec;99(12):6737-6744. doi: 10.1016/j.psj.2020.09.036. Epub 2020 Sep 25.
This study investigated the effect of feed and water access time on yolk sac utilization and subsequent broiler live performance. Hatching eggs were collected from commercial flocks of Ross 308 breeders at 35 and 39 wk of age in experiments 1 and 2, respectively. Chicks already out of their shells that still had some dampness on their down were removed, recorded, feather-sexed, and weighed at 488 h of incubation in both experiments. Chicks were weighed individually and received feed and water at 2 (immediate feed; IF), 8, 12, 16, 20, 24, 28, and 32 h after hatching (488 h) in experiments 1 and 2 (IF) and at 24, 26, 28, 32, 36, and 40 h after hatching in experiment 2. The residual yolk sac weight was determined at 32 and 40 h after hatching (day 0) in all groups in experiments 1 and 2, respectively. Feed consumption and BW were recorded at 7, 14, 21, and 35 d and at the same age relative to placement on feed and water at the end of the growing period. Mortality was recorded twice daily in both experiments. Feed and water access time did not influence yolk sac utilization in either experiment (P > 0.05). The IF group exhibited a higher (P < 0.05) BW than those that received feed at or after 28 h at 35 d in both experiments. There was a significant increase in feed consumption in the IF group compared with the groups with access to feed and water after 24 h at 35 d in experiment 2 (P < 0.05), with a similar trend in experiment 1 (P > 0.05). There were no significant differences in the feed conversion ratio (FCR) or mortality at 35 d of age, but the IF group tended to have a poorer FCR than the other groups in both experiments. When the total feed and water times were equalized among all groups, irrespective of the deprivation duration, there were no significant differences among the groups in the BW, feed consumption, the FCR, or mortality in both experiments. It can be concluded that feed and water deprivation for 28 h or longer after hatching (≥28 h) negatively affects the final BW but tends to improve the FCR at 35 d of age compared with chicks that receive feed immediately (2 h after hatching). When the feeding period was equalized in all groups, feed and water deprivation up to 40 h under optimum conditions had no detrimental effect on final live performance. These results suggest that the total feeding period is more critical for broiler performance than the time of posthatch access to feed and water.
本研究旨在探讨饲料和水的获取时间对蛋黄囊利用和随后肉鸡活体性能的影响。在实验 1 和实验 2 中，分别从 Ross 308 种鸡的商业鸡群中收集 35 周龄和 39 周龄的种蛋。在孵化的 488 小时，将已经出壳但身上仍有一些潮湿绒毛的雏鸡取出、记录、羽色性别鉴定并称重。在实验 1 和实验 2 中，雏鸡在孵化后 2（立即喂食；IF）、8、12、16、20、24、28 和 32 小时（488 小时）以及实验 2 中在孵化后 24、26、28、32、36 和 40 小时（IF）时单独喂食和供水。在所有组中，在实验 1 和实验 2 中，分别在孵化后 32 和 40 小时（第 0 天）测定残余蛋黄囊重量。在 7、14、21 和 35 日龄以及生长阶段结束时相对于放置饲料和水的时间记录饲料消耗和 BW。在两个实验中，每天两次记录死亡率。在两个实验中，饲料和水的获取时间均不影响蛋黄囊的利用（P>0.05）。IF 组在两个实验的 35 日龄时，比在 28 小时或更晚喂食的 BW 更高（P<0.05）。与在 35 日龄时在 24 小时后获得饲料和水的组相比，IF 组的饲料消耗在第 35 天有显著增加（P<0.05），在实验 1 中也有类似的趋势（P>0.05）。在 35 日龄时，体重、饲料转化率（FCR）或死亡率均无显著差异，但 IF 组的 FCR 比两个实验中的其他组差。当所有组的总饲料和水时间相等，无论剥夺时间如何，在两个实验中，BW、饲料消耗、FCR 或死亡率在各组之间均无显著差异。综上所述，与立即（孵化后 2 小时）喂食的雏鸡相比，孵化后 28 小时或更长时间（≥28 小时）的饲料和水剥夺会对最终 BW 产生负面影响，但往往会提高 35 日龄时的 FCR。在所有组中使饲养期相等时，在最佳条件下最多剥夺 40 小时的饲料和水对最终活体性能没有不利影响。这些结果表明，与孵化后获得饲料和水的时间相比，总饲养期对肉鸡性能更为关键。
