Sex Change in Poultry
In a normal female bird only the left ovary is active. Due to infections or other problems, this ovary may cease to function. In that case the right overy becomes active, but for some reason produces more testosterone and causes the bird to develop male plumage and secondary sex characteristics, although it will never become fully male. Hens may begin to crow and usually stop laying.
Some examples are found below.
This Golden Pheasant hen was 3 years old in the left
picture and the right was taken 3 months later. As a two-year-old she had normal
female plumage and laid eggs. After the plumage change she no longer laid.
Photos courtesy of Joe Langly
This is an 18-year-old peahen. She had female plumage and
laid eggs until she was about 14, when she grew the male feathers after a molt.
She never fans her train.
Photo courtesy of Carolyn Dunn
"Kristina Kwacz" -- this utility Buff Runner has undergone a sex change -- note the drake feather. She was a '98 hatched bird and developed the male plumage and stopped laying in about 2001
The first shot is of a Black-shouldered peahen in 1992; in 2006 she
started changing colors. Here are two pictues of her in 2007
Photos courtesy of Lucky Newton
This is a female Red Golden that started to change to male
plumage after a couple years of laying. At this point (around 6) she is still
laying. First signs, 3 years ago, were her crest turning orange (not gold like
the male) and she got a long male-patterned tail. Each year since she's gotten
more male plumage, tho' not quite the normal coloring. The male she is with still
courts her.
Photos courtesy of Jan Peterka
Sex change Links:
An article on a Wyandotte bantam, now a rooster
Direct questions and comments to Barry at FeatherSite -- questions and comments