OTTB Won't Gain Weight

So my guy has been at my barn for a month now, and we can't get weight on him. He's getting about 8-9 quarts of Mana Pro Sweet 10 High Fat w/ beet pulp, weight builder, a flake of alfalfa am and pm, and I keep coastal in his stall at all times for him to eat while he's in there. He's in a paddock most of the day and night, though, and it's all dirt...no grass or hay. He's the only skinny horse in the barn. His butt is continuing to loose fat too. He's 2 months off the track.
I can't add corn oil or wet beet pulp as he won't eat anything wet (he's picky that way). I'm not working him right now as I'm still giving him time to settle in from coming off the track. (he ran his last race march 4). I've considered moving him to a barn w/ grass pasture for him to stay out in, but we may be moving across the state very soon and I don't want to put him through undue stress. If we don't move, then I'll find another barn. If we do, I have one in mind that I'll look at on Friday that seems like a good prospect.
Does anyone have any additional suggestions? I've researched an ulcer but his only "symptom" is lack of weight gain. Can anyone help? My BO's only advice is to start working him. She has a lot of experience w/ OTTBs and has known quite a few that just won't keep weight on unless they're being worked. I'm at my witts end. A month of breaking the bank of feed and no weight gain to show for it. *sigh*

A month is really not that long in the scheme of things with weight gain. The first thing that pops out at me is that he is in the paddock most of the day and night and has no forage (from your description). That would be the first change I would make. Find a way to provide free choice hay of good quality to him 24/7 and you'll be amazed at the turn around that he will likely make.

I'm having problems too with my OTTB and weight, so let me just share what I've learned.

First thing, up his hay. Coastal is good for munching, but has ZERO nutritional value...its like eating white bread all of the time. Straight alfalfa might make him hot, so try getting some T&A or O&A. My guy is on 5 flakes a day and doing zilch, I wish he could be on like 6 but I don't have the money for that. I'd say to start with, try for at least 4 flakes a day.

Take him off the sweet feed. 8-9 quarts is like 10 pounds or something. That's probably contributing to any gastric problems he may have. Go for something high in fat and fiber to aid in digestion. Senior feeds are really good for this. I've heard Purina Horse Chow 100 is an excellent feed as well. It also has some "hay extender" qualities, so if you can't get good quality hay or pasture, you can give him some of that and it will balance out. You can also consider adding something like stabilized rice bran in addition to the beet pulp.

Some horses don't show any outward signs of ulcers. I'd have him scoped anyway, or at least pick up a couple of syringes of Ulcer Gaurd, one syringe lasts you two days, so pick up like 3 and give them to him for a week, and see if there are any changes.

Also look at his stall and turn out habits. Does he come in really sweaty? When he's in, does he pace, circle, seem really fidgety? What about his poop? Is it loose, firm, wet, dry? How are his gut sounds? These can be signs of different forms of gastric distress.

If he seems up to it, I would go ahead and start working him. Even hand walking for 20 minutes up and down the road and around the yard would help if you don't have a place to lunge him, or he doesn't know how to lunge.

Just give him time.

That said, sweet feed isn't the best for thoroughbreds IME. The high starch and sugar in most sweet feeds and even most feed pellets tends to make thoroughbreds hyperactive, which makes them burn more calories, which makes them need more feed. It's a bad cycle.

Instead of the sweet feed, I'd have him on a low starch or "lite" feed, or a ration balancer. A probiotic to help him process his food might not be a bad idea too. Something like Fastrack or Missing Link.

For added fat, use rice bran. I find that it works better than "weight builders", plus it gives the horse a shinier coat and helps foot growth. Horsetech.com can do a custom blend. You want 4-8 oz of flax a day. You have have them add probiotics to aid in digestion, some extra b-vitamims for calming, and anything else you might want thrown in. Their prices include shipping.

Make sure he has lots of turn out, at least 8-10 hours a day. He needs pasture time to mentally decompress and run off any excess energy.

I have dealt with a few thin TBs and they all did wonderfully once I removed grain/sweet feed or feed pellets from their diet.

Coastal Bermuda hay DOES have good nutritional value, if you buy it from a good producer. All we feed is different varieties of Bermuda grass hay and we have great luck. I don't have to feed hardly any "feed" or extras to keep weight on even my hardest keepers. They all have great feet, coats, and overall health as well.

Yes, I agree.

Annie had that same problem when she came off the track. And still its dificult. Racehorses. Hmph, its like consistenly putting weight on a skeleton. I currently have Annie on Two butter-tubs of Omolene 200 twice a day with Biotin, Weight Builder, Beet Pulp, Super 14, and Sweet Feed. She gets five flakes of Alfalfa a day(We get super dense stuff) and still open range on grass for nearly twelve hours a day. Trust me. Racehorses are difficult.

What has worked wonders on our TB is free choice grass hay (actually this last batch has a bit of alfalfa mixed in with it), rice bran and strategy.
I do agree that you are feeding an excessive amount of sweet feed. You are wasting your money, imo, as you are not going to see the weight gain you want and are feeding far more than you would need to were you to switch to a higher quality feed (which would make the price difference a wash, if not save you some $$$).
I've had success using quality hay, beet pulp and alfalfa pellets as well.

This is what I mean. You're pouring all of this high energy feed and hay into a horse and not seeing good results. On this much feed and hay, she should be fat! But, TB and other hot blooded horses don't utilize carbs and sugars the way other breeds of horses do. The more high sugar/starch feed or hay you feed, the more "active" the horse gets, the higher their metabolism goes, and the more calories they burn, so they need more food!!!

Even just 1 lb of plain oats made by TBxArab gelding lose a little weight and become a bit "hyper". Once we switched his diet, his weight held wonderfully and he has turned in to a puppy dog in personality, lol.

My current "hard keeper" TBxArab gets free choice mixed grass hay (bermuda with local grasses mixed in), 1lb of ADM's StayStrong Mineral Pellets (concentrated feed), 1/2 lb of chopped alfalfa hay (slows him down, he gulps his feed down...), 1.5 lbs of Timothy hay pellets, and 3 oz of Uckele's Cocosoya oil. That's it! No weight gainers, no sweet feed or grains, just a simple diet with good fat.

My last TBs were on similar diets. I have used flax meal successfully, and rice bran, both at a rate of 1/2 to 2 cups a day, depending on the horse. Beet pulp works if you have a horse that gets hot on alfalfa. Otherwise I prefer alfalfa pellets and/or chopped alfalfa hay. We don't get baled alfalfa hay in Arkansas very often. We have blister beetles around here, so most hay producers grow some form of bermuda.

Less is more when it comes to hard keepers, especially TBs or similar breeds. Hay, hay, and more hay, with as simple and "natural" of a diet as possible works best. (IME)

We have a OTTB who has always had problems with her weight. Even when she was getting fed 3 times a day and a good bit at that, she would maintain and sometimes even lose weight. They only thing that has made her gain weight and keep it is 24/7 turn out in good grass. All the weight builders in the world wont do what good grass can.

Totally agree. My mare has bermuda 24/7 and gets 2c A&M+1c Stabilized rice bran+1/2 scoop Accell and she is in great condition/weight being trail ridden barefoot 6+ days a week.

I highly recomend Stabilized rice bran (just did on another thread today, lol) More info about it here: Natural Glo - Stabilized Rice Bran

And as others have said you're going to need more time to see improvement. Since you're noticing a drop in weight though I would suggest adding the SRB.