Aggressive gelding - help!

[MissieSFW]

Hi everyone, just wondered if you could help with a management issue we're having.
I keep 3 horses at home, 2 geldings and 1 mare. One of the geldings (who belongs to a friend) has become very aggressive and riggy since the mare arrived in September. He is really possessive of her and demonstrates some very alarming stallion-like behaviour towards the other gelding and will attack him if provoked eg. if he comes too close to the mare, and also at feed-time. He also herds the mare to keep her away from the other horse. When he's like this he can be quite dangerous - I nearly got caught in the crossfire at bringing in time today as he was so busy attacking the other horses he wouldn't be caught and very nearly ran me over!
In the summer it was easy to keep them all separate in individual paddocks but now they've moved into winter quarters I'm really struggling to work out the best field arrangements for them all. In the winter I have one 2-acre field plus 2 sand turnout areas (both of which are fully fenced) which back on to the winter grazing. To save my grazing the idea is that they will go out on the grass alternate days (1 individually and the other 2 together) and spend the rest of the time in the sand areas. At the moment the aggressive gelding is fine with the mare in one sand area (although he does chase her around and bite her from time to time), and then the other gelding is separated to minimise the fighting. But I'm worried I'm encouraging his possessive behaviour by allowing him free access to her 24/7. What I would ideally prefer is to have the aggressive horse separated, BUT I can't put the 2 geldings together in an enclosed area as they just fight, and the mare is a typical mare and stresses if on her own or separated too far from her abusive boyfriend ;( The other problem is that my other gelding is a real fatty who needs restricted amounts of low quality hay, while the mare is an ex-racer and needs ad lib hay and lots of hard feed to keep weight on, so having those 2 together is not ideal anyway!
Quite how we have ended up with 3 such incompatible horses I'll never know but if anyone has any genius ideas on things to try I'd love to hear them! At the moment I feel my options are:
1. Leave aggressive gelding with the mare and keep the other gelding separate - but am I just feeding her separation anxiety and his possessiveness?
2. Put mare with the other gelding and keep Mr Aggressive on his own, hope that she settles without her boyfriend and accept that fatty's diet is probably not going to work
3. Separate the mare and hope that a) she gets used to being on her own and b) the 2 geldings don't kill each other!

Gah! Sorry this is so long but they are a total nightmare! Help please?!

 

[Makemineacob]

I would immediately separate and run your herd with whoever is settled. If your mare and gelding are fine out together and your friend's gelding is causing problems(?) then I'm afraid you need to discuss it with her and keep him separate, otherwise you are going to end up with your horses injured at least! We run ours as a herd and all have different dietary needs but you just need to plan well in terms of feeding times and isn't as difficult as you think.

 

[EQUIDAE]

Angus castus can work wonders for behaviours like that - it's the active ingredient in Rig Calm. Don't waste your money on supplements as you can get it full strength in tablets and just pop it in a piece of apple.

 

[Fiona]

I'd go with option 2 and put mr possessive on his own.

With regards to the feeding incompatibility of your mare and gelding, I guess u can balance it out by feeding the mare her extra rations at night time in her stable....

Fiona

 

[smellsofhorse]

I'd go with option 2 and put mr possessive on his own.

With regards to the feeding incompatibility of your mare and gelding, I guess u can balance it out by feeding the mare her extra rations at night time in her stable....

Fiona

I agree with this.
Also you could out a muzzle on your gelding when it is the mare and geldings turn out in the grass paddock.

Also as someone said, speak to the owner, try a supplement but if horse won't settle then it will have to go!

 

[Orangehorse]

How annoying for you. This is why livery yards often have separate mare and gelding turnout fields, in case one gelding gets very possessive. Good ideas above, main object is to keep your horses safe, and you of course.