Low Temperature Effects on Embryonic Development and Hatch Time

Abstract

A series of experiments was conducted to estimate phenotypic correlations between incubation characteristics, and to evaluate the effects of cold stress and genotype during incubation on chick weight, egg weight loss, hatching time, and embryonic mortality. Eggs were cooled at 18 or 24 C, for 12, 24, 36, 48, or 72 h beginning on Day 8, 12, 14, 16, or 18 of incubation. Other eggs were cooled intermittently for 6 h every 48 h or 12 h every 96 h. A control group in each experiment was not cold stressed. Results indicated a low and negative correlation between hatching time and chick weight, and a low and positive correlation between hatching time and weight loss from transfer to hatching when variability due to egg weight was removed. Chick weights at hatching were lower in chicks from cooled eggs than those of chicks from eggs incubated under normal temperature. The chicks from cooled eggs were more susceptible to dehydration during holding in the hatcher. Incubation times were delayed approximately as long as the times of embryonic cooling. Embryonic mortality was significantly increased under continuous (single period) cold stress, but not under intermittent cooling (6 h every 48 h). Significant genotype by environment interactions were found in the response of embryos of various strains to cold stress. Exposure for 36 h or longer had detrimental effects on chick weight and embryo viability, but these effects were modified by interactions among the factors involved. The results indicated that embryos from cooled eggs lose more weight during incubation and that the neonatal chicks are more susceptible to dehydration during holding time, and have a longer incubation period, and a greater embryonic mortality.

Incubation and rearing temperature effects on Hsp70 levels and heat stress response in broilers

“…Chicks from the group incubated at low temperatures were smaller (non-statistically analyzed), corroborating the results of Suarez et al (1996). Since egg weights in the present study were similar between treatments, the difference in chick weight must have been caused by different water loss during incubation or by the size of residual yolk sac.…”

“…Suarez et al (1996) observed that weight loss during incubation was higher for chicks that had been cooled and they were more susceptible to dehydration when waiting to be serviced. Weight loss depends on the relative humidity during incubation, which was similar among treatments, and eggshell porosity, which was not evaluated in this study.…”

In ovotemperature manipulation influences embryonic motility and growth of limb tissues in the chick (Gallus gallus)

“…It would be interesting in future studies to examine whether this is the case and, if so, whether this would have any effect on the timing of hatching. Previous studies have shown that decreasing temperature can cause delayed hatch times (Suarez et al, 1996), so it might be predicted that our temperature regime might subtly reduce the length of incubation.…”

Incubation of Japanese Quail Eggs at Different Temperatures: Hatchability, Hatch Weight, Hatch Time and Embryonic Mortality

“…There are several studies that observed the effect of temperature on length of incubation (Michels et al, 1974;French 1994, Suarez et al, 1996, on the rate of embryo growth (Decuypere et al, 1979;Dias and Muller, 1998), and on hatchability (Wilson, 1991;Lourens et al, 2005). However, there are few studies about these effects on Japanese quail incubation performance.…”

“…The incubation time can be influenced by many factors like temperature (Suarez et al, 1996;Wilson, 1991), egg weight (Burton and Tullet, 1985), age of breeder (Smith and Bohren, 1975) and also preincubation storage (Bohren, 1978). Incubation temperatures above the optimal temperature have been reported to accelerate growth rates of avian embryos (Romanoff, 1960;Christensen et al, 1999).…”