Functional Ovary in Adult Chicken

In adult chicken, which ovary/oviduct is functional?

Correct Answer: Only left ovary is functional

In adult poultry (hen), only the left ovary and left oviduct remain functional. At birth, both ovaries and oviducts are present, but the right ovary and right oviduct regress and atrophy during development.

Why Only the Left Ovary?

• This is an evolutionary adaptation — having two functional ovaries simultaneously could cause problems with the large egg-laying process.
• The right ovary typically regresses during embryonic development, and only the left persists in most birds.
• In some raptors (hawks, falcons), both ovaries may be functional.

Shape and Appearance of the Active Ovary

• Active ovary in poultry resembles a bunch of grapes due to the multiple follicles (developing yolks) at various stages of maturation.
• A typical laying hen has 5–6 large yellow follicles plus numerous smaller ones.

Why Other Options Are Wrong

• Only right ovary → incorrect; it is always the left in domestic fowl.
• Both functional → correct only in a few raptor species; not in domestic fowl.