Horse lost weight on 80 acres

Hello I am the proud owner of 7 horses, all are fat and happy except my newest one Shygirl, who was given to me because she had an extreme fear of people and severe anxiety which is getting better now that she has been here for a while. My horses are all on pasture. 5 are at my ranch 2 on a hill about 20 acres are fat, and 3 on permanent pasture(the harder keepers) but they look great and 2 are at my house on 80 acres. One I have to have the grazing muzzle on or keep her in a small pen because she founders when she gets to fat(which she is pretty fat right now in a small pen being fed 2 flakes of hay twice a day) but shy on the 80 acres is loosing weight, im feeding her our own grass hay about half a bale a day and also she is getting plenty of grass. Im going to worm her next week and see if she improves(she was wormed a month ago), I would feed her grain every day but on 80 acres with a pond she doesn't usually come in to eat unless she is very hungry(she isnt eating her hay I just checked its still up there in the barn). She is a little ribby and the top of her withers come out just a little, im not in very cold country so I don't think its from a 'hard winter' I was feeding her grain until she 'attacked' my little brother in the morning thinking he had grain. If she doesn't put weight on im wondering what the best thing to do would be(she already saw a vet who said she was healthy and her teeth were fine). Also im not currently riding the horse and I work with her about 3 times a week just getting her used to being around me and following small commands. Any suggestions to get her to gain some weight would be appreciated. Also looking for a high protein supplement for both my horses and my VERY high energy labrador retriever who runs all day everyday. Thanks :) im trying to attach a pic of her I took this morning(cant figure out how) of her in the rain although her ribs arent noticable in the pic.

How long has she been in this new living situation? I wouldn't worry if the change was recent and you do state that she isn't totally at ease with the new situation. When you see her out in the pasture is she eating? It's very easy to get horses in large pastures to come up for grain. She does sound motivated for grain so just get in a pattern of bringing her up at a set time (dusk is a good trigger). Halter her, get her out of the pen so the other horses leave her alone plus you have the opportunity to reinforce some good manners.

Roasted soy beans are a great high quality protein and high fat source for horses.

I used corn oil for a shiny coat on my gelding, but it also put weight on him too. My high strung mare was losing weight like crazy when we first bought her. She was getting 14 lbs of grain a day with senior feed and weight building supplements plus free choice hay and on a pasture. She was always nervous because she didn't know the people or the new place. After about 2 months she settled down and started to relax and stopped losing weight. She still gets the same amt of food to maintain her weight though. What breed is this horse? My TB's always looked thin compared to the Irish Sport Horses they were out with, but they were completely healthy. I'd also say ribs aren;t bad as long as the horse is fit. My gelding was racing fit when we got him and ribs were seen, but he was perfectly healthy. Now he's fat and happy :)

Soaked beet pulp is high in fiber, a filler and helps to gain weight. Try a different wormer then the last. Each wormer attacks different worms for different times of the year. I would go with an Ivermectin based wormer for this time of year.
She could be stressed with the new environment and may possibley have ulcers.

If you know the previous owner is telling the truth about worming a month ago, I would not worm her without taking a fecal sample to the vet first.

Being such an anxious horse that has now found herself in a new living situation, it's possible she has ulcers. Worming her a second time in four weeks would only make things worse, if that's the case.

You sound to live quite a ways out of town but hopefully you have access to a vet that can evaluate her, sooner than later

Since you have already had her teeth checked by the vet, I would consider the possibility that she has ulcers. Horses with ulcers are often fussy eaters. Then you have the cycle of her not eating enough causing more acid in her digestive system irritating her gut and making the ulcers worse. You could talk with your vet about this possibility and if you can, get an internal scope done to confirm. Or you could put her on an ulcer medication and see how she responds. Omeprazole is a the less expensive route, but not all ulcers respond well to it. It only decreases the acid production. Gastroguard is more expensive, but provides a coating to the gut as well as decreases the acid production.

A probiotic is also recommended for unthrifty horses like this mare. A product we have had good results with is Equine Choice.

Grain and processed feeds irritate ulcers. So try replacing her grain ration with soaked beet pulp (the plain kind without molasses added). Alfalfa is good for neutralizing some of the stomach acid as well.

I would have her come in for grian but usually she is two hills over and she is very hard to catch(even with grain if you grab her halter she swings her head away and has almost broken my arm and has tried to trample me to get the grain) I tried Putting her in a pen away from the other horses and she went through three fences and broke 9 posts to get to them(Amazingly with only a small cut) She went through a wooden fence a barb wire fence and a no climb 7 foot fence(yes in the same day) And broke a very large pine pole post in half. She also took out a metal gate. SO I no longer try to separate them. This horse was very abused when she was given to me and had a large cut on her face from being beaten with a two by four. The first 3 weeks I had her she got strategy with an ulcer relieving suppliment and a hoof suppliment and wheat germ oil and probiotics(Introduced slowly, I have it all with so many horses)and that didnt seem to help but it did make her very hot and hyper(I don't think she ever had grain before). She also has face issues(getting better), once I moved to fast to put a halter on her and she swung her face at me and knocked me clean out. Im not concerned with her training yet I would just like her to gain weight. She has free feed hay. It could be anxiety causing this but the way iv fixed horses before(leaving them in a pen and working them daily not allowing them around other horses) doesnt work for her because she doesnt care about fences.

She eats if my other horse eats. If my other horses isnt eating she isnt, and she wont eat her hay she is to happy with the grass.

Yes I do live far from town, if she doest calm and gain weight the next few weeks she will be hauled to the vet, as she is only a little ribby right now and far from an emergency. I wormed her a month ago(When I first got her she hadnt been wormed since they got her as a 2 year old)

she is a quarter horse her grandfather is doc o'lena