cortisol levels, need advice

[muffy32]

My horse has started behaving quite differently when I go to get him in from the field, he is usually a really cuddly guy but two days on the trot he has let me appraoch him and then tried to kick me.
Somebody mentioned that horses with high Cortisol levels tend to be like this, quiet and lovely and then stressed and aggressive.
I need to find out all I can about Cortisol and its possible effects on behaviour, I know that it is found in high levels in horses with cushing disease and is somehow linked to laminitis.

can anyone offer me any info?

 

[pottamus]

Is this something that has happened recently? And is he rugged? Cannot help with the Cortisol query but my horse turned into devil horse this week because he feels the change in temperature...he is like it every year. Putting a rug on him has changed him back into his cute cuddly self again...literally overnight!

 

[ihatework]

I know that in humans there is currently ongoing research looking at cortisol levels in relation to depression.
It might be worth having a good google and seeing what you can find in humans, as some of this may translate to horses.

 

[burrows]

I did some research at college looking at the effects of feed and exercise on cortisol levels in the horse. Cortisol is responsible for stimulating the conversion of proteins to carbohydrates, and is often seen to rise with exercise and in response to stress. The production of cortisol is stimulated by two main factors; emotional stress and stress encounter in physical exertion. Resting levels of cortisol will naturally have large fluctuation throughout the day being highest in the morning and lowest late afternoon.

The temperament/demeanour of the horse has a great effect on resting cortisol levels:
- if a horse is nervous, aggressive or excited then cortisol will be higher.

I wouldnt have thought that having high levels of cortisol would make your horse aggressive as it is mearly something that is produced in response to stress. If you tested Cortisol level when your horse is being stressed/aggressive they would probably be high, but not the cause of his behaviour. I hope this is some help.