Aggressive mating behaviour: a recent review of the literature

[CoopBoots]

Can anyone speak to the 'psychological castration' hypothesis?

i.e. "roosters that mature later may be subjected to female dominance, which can lead to inhibition of reproductive behavior. This form of “psychological castration” is considered irreversible [22]."
Ref 22 is Bestman, M.; Ruis, M.; Heijmans, J.; van Middelkoop, K. Poultry Signals: A Practical Guide for Bird Focused Poultry Farming; Roodbont Publishers B.V.: Zutphen, The Netherlands, 2020, which I have not seen.

I might have something to contribute here.

I have a boy I jokingly call my "eunuch rooster" who stays with my hens without making sexual advances. He did at first as a cockerel--but was pretty easily deterred by the grown hens and my dominant rooster. He even used to crow. Now he has given up all such behavior as far as I can tell. No daytime crowing, no grabbing, no chasing, no chest bumps or "noticing" a vulnerable hen and using the opportunity.

I was disappointed with the absence of crowing, and then further with the absence of any observed mating, as I find him a very pretty rooster. The closest thing to male behavior he's got is shooing away cockerels who ARE interested in the girls, and being confident enough to shoo away some competition at the feeders. He generally just growls and uses his massive size to push his way in. He's still very "cautious" and can be easily frightened away if a hen stands her ground, but he comes at the end of feeding sessions and they mostly just get out of his way now. He doesn't even seem to peck anyone at roosting time!

I'm hoping he's not permanently altered, but he DID show sexual behavior and attempts as a cockerel. His first molt didn't help speed things up, and he's just getting over that now. But all he's interested in is standing around with the hens and staying out of the boss rooster's way. I'm interested to see if he wakes up at all this spring...

 

[Perris]

I might have something to contribute here.

I have a boy I jokingly call my "eunuch rooster" who stays with my hens without making sexual advances. He did at first as a cockerel--but was pretty easily deterred by the grown hens and my dominant rooster. He even used to crow. Now he has given up all such behavior as far as I can tell. No daytime crowing, no grabbing, no chasing, no chest bumps or "noticing" a vulnerable hen and using the opportunity.

I was disappointed with the absence of crowing, and then further with the absence of any observed mating, as I find him a very pretty rooster. The closest thing to male behavior he's got is shooing away cockerels who ARE interested in the girls, and being confident enough to shoo away some competition at the feeders. He generally just growls and uses his massive size to push his way in. He's still very "cautious" and can be easily frightened away if a hen stands her ground, but he comes at the end of feeding sessions and they mostly just get out of his way now. He doesn't even seem to peck anyone at roosting time!

I'm hoping he's not permanently altered, but he DID show sexual behavior and attempts as a cockerel. His first molt didn't help speed things up, and he's just getting over that now. But all he's interested in is standing around with the hens and staying out of the boss rooster's way. I'm interested to see if he wakes up at all this spring...

Thanks for that; I found it very interesting.

I have a male who turned 1 in June so is a full grown roo now, and his behaviour is the same, though he does occasionally crow. He has (and has had since he was a juvenile) stiff flat feet, and a peculiar gait, and he shows no interest at all in mating though, like yours, he did when he was a teen. I used to worry he was in pain, but he's not depressed, and I'm sure he's glad to be alive, so I haven't euthanized him. He performs useful roles despite his deficiency in locomotion; he has been seen looking after a broody and chicks, and keeping an ill hen company and a chick warm. I think they all know they can rely on him for protection and that he won't even try to mate. So he's a valued and fully integrated member of the flock. And in terms of genetics, he thinks he is (and he actually is) related to the roos that do mate, so there may be an element of communal genes altruism going on.

 

[Ridgerunner]

Can anyone speak to the 'psychological castration' hypothesis?

I'm hoping he's not permanently altered, but he DID show sexual behavior and attempts as a cockerel. His first molt didn't help speed things up, and he's just getting over that now. But all he's interested in is standing around with the hens and staying out of the boss rooster's way. I'm interested to see if he wakes up at all this spring...

It would be interesting to see what would happen if his competition were removed.

I grow out several cockerels every year with the flock. Of course it is more complicated than this, but they generally form a sub-flock of their own with the pullets. A few of these cockerels are aggressive in trying to dominate but several are submissive, not fighting the other cockerels for dominance of this sub-flock or trying to mate the pullets. And the dominant ones usually leave them alone. I practically always choose one of the more dominant cockerels as the eventual flock master so I don't get to see it, but I'd expect a submissive one to step up if the dominant competition were gone.

I wonder if psychological castration is just another way of saying "submissive". Is it permanent or situational? As each chicken has its own personality I'd expect you to get different results with different chickens.

But I generally choose a more dominant cockerel to become flock master on the theory that a male with a dominant personality can maintain control over the flock based on force of personality as opposed to brute strength.

 

[CoopBoots]

It would be interesting to see what would happen if his competition were removed.

I grow out several cockerels every year with the flock. Of course it is more complicated than this, but they generally form a sub-flock of their own with the pullets. A few of these cockerels are aggressive in trying to dominate but several are submissive, not fighting the other cockerels for dominance of this sub-flock or trying to mate the pullets. And the dominant ones usually leave them alone. I practically always choose one of the more dominant cockerels as the eventual flock master so I don't get to see it, but I'd expect a submissive one to step up if the dominant competition were gone.

I wonder if psychological castration is just another way of saying "submissive". Is it permanent or situational? As each chicken has its own personality I'd expect you to get different results with different chickens.

But I generally choose a more dominant cockerel to become flock master on the theory that a male with a dominant personality can maintain control over the flock based on force of personality as opposed to brute strength.

My current plan is to keep him, so if he ends up inheriting the flock or challenging the status quo I'll be happy to update.

He's a good couple of years younger than my current flock leader so I guess there's always a chance!