Department of Poultry Science, University of Georgia, Athens, GA 30602, USA.
Department of Population Health, University of Georgia, Athens, GA 30602, USA.
Poult Sci. 2023 Sep;102(9):102853. doi: 10.1016/j.psj.2023.102853. Epub 2023 Jun 17.
Broiler breeder feed restriction practices have intensified as broiler feed efficiency has been improved. Skip-a-day (SAD) rearing regimen has controlled breeder growth, although this practice has become questionable for the modern breeder. We compared everyday (ED) and SAD programs and evaluated their impact on pullet growth performance, body composition, gastrointestinal tract development, and reproduction. At d 0, Ross 708 (Aviagen) pullet chicks (n = 1,778) were randomly assigned to 7 floor pens. Three pens were fed using the ED and 4 pens with SAD program through wk 21 using a chain-feeder system. ED and SAD grower diets were formulated to be isonutritious, with the only difference that ED diets had more crude fiber. Pullets (n = 44 per pen) were moved to 16 hen pens by treatment at wk 21 with 3 YP males (Aviagen) in each pen. All birds were fed common laying diets. In addition to BW data, sampled pullets and hens were scanned using dual energy X-ray absorptiometry (DEXA) to obtain body bone density and composition. Hen performance and hatchery metrics were recorded through wk 60. ED birds were heavier with similar nutrient intake from wk 10 to 45 (P ≤ 0.013). Pullet uniformity was unaffected by feeding method (P ≥ 0.443). SAD pullets had less body fat at wk 19 (P = 0.034) compared to ED pullets, likely as a metabolic consequence of intermittent feeding. SAD birds had lower bone density at wk 7, 15, and 19 (P ≤ 0.026). At 4 wk of age, SAD pullets had less intestinal villi goblet cells compared to ED pullets (P ≤ 0.050), possibly explained by the effect that feed removal has on cell migration rates. Overall egg-specific gravity (P = 0.057) and hatch of fertile % (P = 0.088) tended to be higher in eggs from ED hens. Altogether, ED feeding increased young pullet intestinal goblet cells and increased both bone density and body fat at wk 19. ED program improved pullet feed conversion (2.6% less feed) and increased eggshell quality and hatch of fertile.
肉种鸡限饲措施随着肉鸡饲料效率的提高而不断加强。尽管这种做法对现代种鸡来说已经受到质疑，但隔日（SAD）饲养方案控制了种鸡的生长。我们比较了日常（ED）和 SAD 方案，并评估了它们对育成鸡生长性能、体组成、胃肠道发育和繁殖的影响。在 d 0 时，随机分配罗斯 708（Aviagen）育成鸡雏（n = 1778）到 7 个地板笼中。3 个笼使用 ED 方案，4 个笼通过 21 周的链式喂养系统使用 SAD 方案。ED 和 SAD 育成鸡饲料的配方是营养平衡的，唯一的区别是 ED 饲料的粗纤维含量更高。在 21 周时，根据处理将育成鸡转移到 16 个产蛋鸡笼中，每个笼中加入 3 只雄性 Aviagen 公鸡。所有鸟类均饲喂普通产蛋鸡饲料。除 BW 数据外，还使用双能 X 射线吸收法（DEXA）对采样育成鸡和母鸡进行扫描，以获得体骨密度和组成。通过 60 周记录母鸡的生产性能和孵化场指标。从第 10 周到第 45 周，ED 鸡的体重较重，养分摄入量相似（P ≤ 0.013）。饲喂方法对育成鸡的均匀度没有影响（P ≥ 0.443）。与 ED 育成鸡相比，SAD 育成鸡在 19 周时体脂较少（P = 0.034），这可能是间歇性喂养的代谢后果。SAD 鸡在 7、15 和 19 周时的骨密度较低（P ≤ 0.026）。在 4 周龄时，SAD 育成鸡的肠道绒毛杯状细胞比 ED 育成鸡少（P ≤ 0.050），这可能是由于饲料去除对细胞迁移率的影响所致。总体而言，ED 母鸡所产蛋的蛋比重（P = 0.057）和受精率（P = 0.088）较高。总的来说，ED 饲养增加了幼鸡肠道中的杯状细胞，并在 19 周时增加了骨密度和体脂肪。ED 方案提高了育成鸡的饲料转化率（少消耗 2.6%的饲料），并提高了蛋壳质量和受精率。
