Hens sex change

Chickens can and do change sex, a well know fact among egg farms. The known occurences happen about every 1 in a 10,000. It has been observed that an egg-laying hen change into a crowing/breeding rooster. There are numerous explanations for this most having to do with the keeping the species going. But it is observed in egg-laying barns where no roosters have been present that a hen will change. When males turn into females, it's called protandry, and when it's the other way around, it's called protogyny. Only fish and some invertebrates demonstrate sequential hermaphroditism.

Some recent chicken sex change examples from the UK

A sex-change chicken which started life as an egg-laying hen has turned into a crowing cockerel.

The pet, called Freaky, spent eight months laying dozens of eggs until she crowed like a cock bird one morning.

Over the next few weeks, she sprouted a scarlet comb, grew red flaps called wattles under her chin and tufty tail feathers - all attributes of cockerels.

Owner Jo Richards, of Saltford, near Bristol, said: "I've kept chickens for 10 years but I've never heard of such a thing."

Animal experts said Freaky's sexchange was a one-in-10,000 rarity. It happens when a damaged ovary causes the hen's testosterone levels to soar, turning the remaining ovary into a testicle.

Freaky, a silver-laced Wyandotte hen, now crows every sunrise, aggressively attacks other males and even tries to mate with his old female friends.

Victoria Roberts, of the Poultry Club of Great Britain, said: "This is very, very rare. I've been keeping poultry for 35 years and I've seen it only once."

Sex Change chicken in Hertfordshire

We have kept chickens for many years purely for the indulgence of fresh free-range eggs. The current population have been kept, as they say, from the egg and the pecking order is well established.

There is no doubt as to which is chief chicken, as it exhibits all the usual manifestations of being the boss including, occasionally, 'treading' the other birds in imitation of a cockerel.

Recently, however, the bird has taken an even bigger step towards cockerelhood - that of trying to crow. Indeed, it has refined its performance to the point where it is indistinguishable from the real thing - to the annoyance of our neighbours whom it wakes at unearthly hours.

Since these birds have never heard a cockerel nor presumably do they know what one is, could it be that they have an archetypal memory of cockerel behaviour in addition to hen behaviour?

If this is the case is it precipitated in a group of birds by the need for a 'boss' figure and only appears in the bird at the head of the pecking order, or does that bird suffer a hormone change which results in the appearance of the latent cockerelness?

In short, is this a case of Henopause requiring HRT (Hen Repopulation Therapy) or has the bird just sexually freaked out?

More weird facts about Chickens