Department of Poultry Science, Mississippi State University, Mississippi State MS 39762, USA.
USDA-ARS, Poultry Research Unit, Mississippi State, MS 39762, USA.
Poult Sci. 2023 Apr;102(4):102506. doi: 10.1016/j.psj.2023.102506. Epub 2023 Jan 16.
The current commercial broiler embryo experiences a rapid metabolism and growth rate and may produce more heat than those of the past. Consequently, it may be beneficial to lower standard incubation temperature for commercial broiler hatching eggs. The purpose of this experiment was to determine if lowering incubation temperature at 12 d of incubation (DOI) would affect embryo temperature (ET) in embryonated Ross 708 broiler hatching eggs. From 0 to 12 DOI, eggs were incubated under standard conditions (37.50°C dry bulb, 29.76°C wet bulb). At 12 DOI, temperature transponders were aseptically placed on the inner air cell membrane to measure air cell temperature (ACT) as an estimate of ET in 120 eggs. The eggs were then randomly assigned to 4 separate still-air incubators, each containing 30 eggs. Two replicate incubators were maintained at a standard (STRT; 37.5°C) or low (LTRT; 35.6°C) temperature treatment between 12 and 21 DOI. A significant positive correlation existed between incubator air temperature (IAT) and ACT across temperature treatment and in the STRT. However, IAT was not significantly correlated with ACT in the LTRT. A significantly higher ACT was observed in the STRT than in the LTRT for 88% of the readings taken between 12 and 21 DOI. Percent egg weight loss (PEWL) between 13 and 17 DOI did not significantly differ between temperature treatments. From 13 to 17 DOI, there was a significant positive correlation between PEWL and ACT in the STRT, however, no significant correlation occurred between PEWL and ACT in the LTRT. Percent hatch of fertile eggs containing live embryos at 12 DOI was 93.3% in the STRT and 100% in the LTRT. However, time of hatch occurred 14 to 19 h later and hatchling BW was lower in the LTRT than in the STRT. Although lowering IAT at 12 DOI may improve hatchability, an associated delay in hatch and a decrease in hatchling BW may not be commercially acceptable.
当前的商业肉鸡胚胎经历了快速的新陈代谢和生长速度，可能比过去产生更多的热量。因此，降低商业肉鸡孵化蛋的标准孵化温度可能是有益的。本实验的目的是确定在孵化的第 12 天（DOI）降低孵化温度是否会影响罗斯 708 肉鸡孵化蛋的胚胎温度（ET）。从 0 到 12 DOI，鸡蛋在标准条件下孵化（干球温度 37.50°C，湿球温度 29.76°C）。在 12 DOI 时，无菌地将温度传感器放置在内气室膜上，以测量气室温度（ACT）作为 120 个鸡蛋中 ET 的估计值。然后，将这些鸡蛋随机分配到 4 个独立的静态空气孵化器中，每个孵化器中含有 30 个鸡蛋。两个重复孵化器分别在标准（STRT；37.5°C）或低（LTRT；35.6°C）温度处理下保持在 12 和 21 DOI 之间。在整个温度处理和 STRT 中，孵化器空气温度（IAT）与 ACT 之间存在显著的正相关关系。然而，在 LTRT 中，IAT 与 ACT 没有显著相关。在 STRT 中，在 12 和 21 DOI 之间的 88%的读数中，ACT 明显高于 LTRT。在 13 和 17 DOI 之间，温度处理之间的蛋重损失百分比（PEWL）没有显著差异。从 13 到 17 DOI，在 STRT 中，PEWL 与 ACT 之间存在显著的正相关关系，但在 LTRT 中，PEWL 与 ACT 之间没有显著的相关性。在 STRT 中，含有活胚胎的可育蛋在 12 DOI 时的孵化率为 93.3%，在 LTRT 中为 100%。然而，孵化时间延迟了 14 到 19 小时，LTRT 中的孵化雏鸡 BW 低于 STRT。尽管在 12 DOI 时降低 IAT 可能会提高孵化率，但孵化延迟和孵化雏鸡 BW 降低可能在商业上不可接受。
