Histomorphological development of the left ovary in poultry during the pre-hatch period: A review with special reference to Kadaknath and white leghorn chickens

Abstract

The development of the female reproductive system in birds is a highly specialized and asymmetric biological process, characterized by functional dominance of the left ovary and regression of the right ovary during embryogenesis. Understanding the histomorphological changes occurring during ovarian development in the pre-hatch period is crucial for improving reproductive efficiency, conserving indigenous poultry breeds, and advancing avian developmental biology. This review critically evaluates the histomorphological development of the left ovary in poultry, with special reference to Kadaknath and White Leghorn chickens. Key developmental milestones, including cortex-medulla differentiation, migration and proliferation of primordial germ cells, transformation of germinal epithelium, formation of sex cords, development of cortical cellular whorls, and breed-specific traits such as fibromelanosis, are highlighted. Comparative insights from other avian species including ducks and dwarf fowl are incorporated to broaden the developmental perspective. The review emphasizes breed-related histomorphological variations and their implications for reproductive performance, conservation strategies, and sustainable poultry production.