Temperature during the last week of incubation. I. Effects on hatching pattern and broiler chicken embryonic organ development

Abstract

We investigated the effects of an eggshell temperature (EST) of 35.6, 36.7, 37.8, and 38.9°C applied from d of incubation (E) 15, E17, and E19 on hatching pattern and embryonic organ development. 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. Moment of internal pipping (IP), external pipping (EP), and hatch was determined, and organ development was measured at E15, E17, E19, IP, EP, and hatch. A lower EST extended incubation duration compared to a higher EST. The lower incubation duration was mainly caused by the extended time until IP, whereas time between IP and hatch hardly varied between treatments. Relative heart weight was affected by EST already from 2 d after the start of EST treatment on E15, and effects became more pronounced at longer exposure time to various EST treatments. At hatch, the largest difference in relative heart weight was found between an EST of 35.6 and 38.9°C started at E15 (Δ=64.4%). From E17 onward, EST affected yolk-free body mass (YFBM) and relative stomach weight, where a lower EST resulted in a lower YFBM and relative stomach weight before IP and a higher YFBM and relative stomach weight after IP. From E19 onward, a lower EST resulted in a higher relative liver and spleen weight regardless of start time of treatment. Yolk weight and relative intestine weight were not affected by EST before and at E19, but a higher EST resulted in a higher yolk weight and lower relative intestine weight from IP onward. Based on the higher YFBM and higher relative organ growth found at hatch, we concluded that an EST lower than 37.8°C from E15 onward appears to be beneficial for optimal embryo development.

Effects of incubation temperature pattern on broiler performance

“…To balance oxygen requirement and oxygen availability in week 3 of incubation, it can be suggested that after E14, a lower EST than 37.8°C might be more optimal. Maatjens et al., 2016a , Maatjens et al., 2016b demonstrated that an EST of 36.7°C or even 35.6°C from E15 onward resulted in a higher YFBM and higher relative heart, intestine, liver, and bursa of Fabricius weights of neonatal chicks than an EST of 37.8°C throughout incubation.…”

“…When temperature is raised during incubation, embryo metabolism increases as broiler embryos act mainly as poikilotherms ( French, 1997 ), suggesting that embryonic development will be stimulated with a higher EST than 37.8°C. For the second week of incubation, this might be true, but in the third week of incubation, a higher EST than 37.8°C has been shown to negatively affect neonatal chick quality and posthatch performance ( Romanoff, 1936 ; Lourens et al., 2005 ; Hulet et al., 2007 ; Leksrisompong et al., 2007 ; Ipek et al., 2014 ; Maatjens et al., 2014b , 2016a ). Hatchlings incubated at an EST higher than 37.8°C during late incubation showed a poorer quality, expressed by a shorter length, more residual yolk ( RY ), worse navel score, and lower weights of various organs relative to their YFBM.…”

“…Based on the studies of Nangsuay et al. (2016) and Maatjens et al., 2016a , Maatjens et al., 2016b , it can be hypothesized that a combination of a higher EST in week 2 and a lower EST in week 3 of incubation may stimulate embryo development and chick quality at hatch compared with a constant EST of 37.8°C throughout incubation. Studies investigating these different EST patterns and the effects on posthatch performance are lacking.…”

The Use of Ostrich Eggs for In Ovo Research: Making Preclinical Imaging Research Affordable and Available

“…At an activity concentration of 13.5 kBq/mL, the recovery coefficients for 18 (21). Considering that the organs of ostrich embryos are naturally larger than those of chicken embryos (e.g., liver size: 15 vs. 2 cm 3 ) (18,22), it is conceivable that imaging is comparable. This aspect has to be evaluated in future studies.…”

Effects of food and water deprivation in newly hatched chickens : a systematic literature review and meta-analysis

“…E.g. Lourens et al [141], Molenaar et al [142], and Maatjens et al [143,144] demonstrated strong effects of incubation temperature on chicken quality at hatching.…”