Reduced O2 concentration during CAM development--its effect on physiological parameters of broiler embryos
1Institute of Animal Science, Agricultural Research Organization the Volcani Center, PO Box 6, Bet Dagan 50250, Israel. druyan@agri.huji.ac.il
Poultry Science
|March 9, 2012
Summary
Exposure to reduced oxygen during embryonic development enhances blood oxygen capacity and growth in broiler embryos. This adaptation may impact posthatch performance and cardiovascular function.
Area of Science:
- Embryology
- Physiology
- Environmental Science
Background:
- Embryonic development is influenced by genetic and environmental factors.
- Environmental changes during embryogenesis can lead to permanent phenotypic alterations.
- Hypoxia is a significant environmental stressor during development.
Purpose of the Study:
- To investigate the effects of 17% oxygen concentration on chorioallantoic membrane (CAM) development.
- To assess cardiovascular parameters in broiler embryos under hypoxic conditions.
- To evaluate embryo development and postexposure effects up to hatching.
Main Methods:
- Two trials with 840 fertile Cobb eggs each.
- Embryos exposed to 17% O(2) for 12 hours daily from embryonic day 5 (E5) to E12.
- Control group received standard conditions.
- Measurements included CAM vascular area, hematocrit, hemoglobin, heart rate, heart weight, and eggshell temperature.
Main Results:
- Hypoxic exposure significantly increased CAM vascular area by 6.8%.
- Hematocrit and hemoglobin levels transiently increased.
- Eggshell temperature was higher in the hypoxic group, indicating increased heat production.
- Increased oxygen consumption and yolk intake were observed in hypoxic embryos.
Conclusions:
- Embryos adapt to hypoxia by enhancing angiogenesis and blood oxygen-carrying capacity.
- Increased oxygen consumption positively affects embryo growth and maturation.
- These adaptations may influence posthatch performance and the cardiovascular system's ability to meet oxygen demands.
