Help feeding a hard keeper?

Hello,

I currently lease a 21yr old Thoroughbred, who's in light work (only ridden one or twice a week for no more then a hour). During summer when the grass is insane, she keeps helself at a good weight, but now that it's coming to winter I know [from last year] that she drops her weight almost instantly. I've already started rugging her, and am feeding her hard feeds one a day containing:
1 chaff, 2 lucerne, 1/2-1 gumnuts, and 1/3 a cup of equisoy.

She seems to be maintaining a decent weight.. BUT I was wondering if anything had any opions of hay pellets.. I've read some online forums about them and have heard that they are great for hardkeepers.

She's paddocked 24/7 with access to stables for shelter, but doesn't seem to held her weight.. Help? :)

Also, here's a photo of herself and I at a show last weekend in a lead Thoroughbred class! :) (Just so you can see her current condition..)

I'm subscribing!

I have the same problem with my 18yo TB, and so does my sister in law, not sure how old her boy is, 9 or 10, maybe, but a TB too. We've literally tried everything... only thing that seems to work is LOTS of good grass. But that's just so hard in winter! I've tried gumnuts, pollard, chaff up the kazoo... and even soy products with no luck. He gets the runs if he has anything too rich, and even slipping hot feeds (behind his daddy's back lol!) in the mix only marginally helps, but he does get hyper and burns through it, but at least then he gets a bit of muscle and looks a little better! I'm tempted to go all out this winter, and try everything I can get my hands on, but I'm getting married this year and just can't afford to buy bags and bags of everything. The wedding also means less time for exercising... and that means less muscle, and he'll look even worse. I might just have too turn him out after the may shows in some massively ridiculous paddock somewhere. :(

I'm not the only one! HURRAH!

Hey pellets! I've heard they work wonders..
""Manage your feeding program carefully for your aged horse. For a horse who is a hard keeper (a horse who eats a large amount of fat- and muscle-building feed, but still does not gain weight properly), adding in soaked hay pellets to the two-to-three-times-a-day feedings of senior feed will do wonders. Beet pulp is also a wonderful addition to a senior feeding regimen, as it aids in weight gain and hind gut health."

How to Feed a Senior Horse for Optimum Health and Weight | eHow.com

I intend to try this, and i'll keep everyone posted.