HatchTech BV, P.O. Box 256, 3900 AG Veenendaal, the Netherlands.
Adaptation Physiology Group, Wageningen University, P.O. Box 338, 6700 AH Wageningen, the Netherlands.
Poult Sci. 2017 May 1;96(5):1451-1458. doi: 10.3382/ps/pew390.
We investigated effects of eggshell temperature (EST) of 35.6, 36.7, 37.8, or 38.9°C applied from d of incubation (E) 15, E17, or E19 onward on chicken embryo physiology. A total of 2,850 first-grade eggs of a 43-week-old Ross 308 broiler breeder flock were incubated at an EST of 37.8°C until E15. From E15, E17, or E19 onward, eggs were incubated at an EST of 35.6, 36.7, 37.8, or 38.9°C. Plasma glucose, uric acid, and lactate concentrations, and hepatic glycogen amount and concentration were measured at E15, E17, E19, internal pipping (IP), external pipping (EP), and hatch.An EST of 38.9°C applied from E15 onward decreased the amount of hepatic glycogen from E19 to IP and resulted in a lower glycogen amount at IP compared to all other EST. At EP, when oxygen (O2) becomes largely available, an EST of 38.9°C resulted in a higher glycogen amount and concentration compared to IP, which suggests that plasma glucose between IP and EP might be used for building up hepatic glycogen reserves. However, hepatic glycogen levels remained considerably lower at IP, EP, and hatch at an EST of 38.9°C, compared to an EST of 35.6 and 36.7°C.Opposite to an EST of 38.9°C, from IP onward, an EST of 35.6°C resulted in a higher glycogen amount and concentration compared to all other EST, which might be caused by the higher O2 availability relative to the lower metabolic rate, which provided time to build up glycogen stores from excessive glucose. A higher availability of hepatic glycogen might contribute to an improved physiological status of the broiler chicken embryo toward hatch. Hepatic gluconeogenesis is crucial for developing embryos, as glucose is the major energy source from IP until hatch. At hatch, no effect of EST was found for glucose, uric acid, or lactate.Results of this study emphasize that EST of 35.6 and 36.7°C from E15 onward appear to be beneficial for chicken embryo physiology.
我们研究了从孵化第 15 天（E）、第 17 天或第 19 天开始，将鸡蛋壳温度（EST）分别设定为 35.6°C、36.7°C、37.8°C 或 38.9°C 对鸡胚胎生理学的影响。共有 2850 枚来自 43 周龄罗斯 308 肉鸡种鸡群的一级蛋在 37.8°C 的 EST 下孵化至第 15 天。从第 15 天开始，E15、E17 或 E19 的鸡蛋在 EST 下孵化 35.6°C、36.7°C、37.8°C 或 38.9°C。在第 15 天、第 17 天、第 19 天、内部出雏（IP）、外部出雏（EP）和孵化时，测量血浆葡萄糖、尿酸和乳酸浓度以及肝糖原量和浓度。从第 15 天开始，将 EST 设定为 38.9°C，从第 19 天到 IP，肝糖原量减少，IP 时糖原量也低于其他所有 EST。在 EP 时，当氧气（O2）大量可用时，与 IP 相比，EST 为 38.9°C 时糖原量和浓度更高，这表明 IP 和 EP 之间的血浆葡萄糖可能用于建立肝糖原储备。然而，与 EST 为 35.6°C 和 36.7°C 相比，在 EST 为 38.9°C 时，IP、EP 和孵化时的肝糖原水平仍然明显较低。与 EST 为 38.9°C 相反，从 IP 开始，EST 为 35.6°C 时的糖原量和浓度高于其他所有 EST，这可能是由于相对于较低的代谢率，O2 的可用性更高，从而有时间从过多的葡萄糖中建立糖原储存。较高的肝糖原可用性可能有助于改善肉鸡胚胎孵化时的生理状态。肝糖异生对发育中的胚胎至关重要，因为葡萄糖是从 IP 到孵化时的主要能量来源。在孵化时，EST 对葡萄糖、尿酸或乳酸没有影响。本研究结果强调，从第 15 天开始，EST 为 35.6°C 和 36.7°C 似乎对鸡胚胎生理学有益。
