How long can she go?

I have a mare that is on her 355th day since the last day of breeding. She is making me really nervous being so overdue. She has mammory development, tail swishing, a little pacey and not eating as well as usual. But she's been this way for weeks. When I check her milk it went from amber colored and sticky to now it is amber and thin, watery.
Has anyone had a mare to go this long overdue and everything still turn out ok?
This is my first baby.Any help is appreciated.

Hi,

One of my instructors mares, went to almost 12 months (twice)! And they were fine, no complications or anything.

call a vet,call a vet,call a vet....if your worried call a vet...it can't hut and there not going ot mind answering your questions at all! hope all goes well

I'm no expert on this, I know this from some experience and from my parents. Mare's are usually late when it's their first foal. Watch for the milk to turn yellow and it should be sweet, if it is, then your about to have a foal. If you are worried, then it won't hurt to call the vet, you can talk to them on the phone and get advice.

It is not at all unusual for a mare to go over due. (especially if carrying a colt) We had a mare last year that was due on May10 only to foal July 10!!!!! I think the only reason she foaled was because she overheard me saying if she didn't foal by "today" then she was going to the vet to be palpated! (I wanted to be sure the foal was still alive.) Mare and colt did fine. If you have any doubts/worries call your vet. Is she waxing yet?

I hope every thing goes fine.... Got my fingers crossed

well, she won't hold it until Christmas, you can be sure of that!! I had a mare go to 368. It happens, hang in there!!

My mare went one day shy of a year and nothing was wrong with either. It is normal for horses to go over. My vet told me anywhere from 11-14 months gestation period!!!