The Effect of Maternal Hormones on the Avian Offspring: A Review

Maternal hormones have a significant impact on the development of avian embryos, controlling vital physiological functions such as immune system development, metabolism control, and productive traits. This review will examine the different types of maternal hormones, synthesis, regulation, and effects on avian physiology and productivity, as well as the implications for embryonic development. Additionally, it appears that how they might affect hatchability and chick quality. Studies have shown that maternal hormones transfer to eggs and subsequently affect the offspring's development, greatly influencing the behavior and phenotype of avian offspring overall. Understanding these mechanisms can help improve our knowledge of developmental biology, parental investment, and evolutionary processes that influence avian traits. Different species of birds may experience different effects when exposed to maternal hormones. For example injecting testosterone into bird eggs can increase the rate at which certain species hatch, such as quail, other species may see a decrease in hatchling weight. This emphasizes the complexity of hormonal influences on bird development and the necessity of more research. In particular, it is still unclear how yolk steroids affect birds' immune systems; early research indicates that they may chickens' ability to produce antibodies. Undertaking further research is necessary to completely understand the implications of avian immunity to fill in these gaps in knowledge across species and developmental stages.