When Tristan was diagnosed with Cushings, I spent a lot of time thinking very thoroughly about each aspect of his diet. There are some pieces of it I still have under review, but overall, I'm happy with where we are right now.
First things first: forage. Tristan gets 2 flakes of grass hay AM and PM. When it's cooler at night, he gets an extra flake or two at night check. When I ride him in the evening, I often (but not always) toss him an extra flake to work on.
Throughout the summer, he was on about 5-6 hours of grass turnout per day. He was pulled off the grass by 1pm each day at the latest, and because he was already going out with the other Cushings horse in the barn (he and the other gelding were until recently joint gay uncle babysitters for the yearling filly), he was always turned out in the medium-to-poor grass pasture anyway.
Now that it's starting to frost over at night, the barn manager is evaluating each day on an individual basis. If the weather has been ok, and the grass hasn't been stressed, they still get to go out on it. If there's been a frost or chill overnight, Tristan and Pari are put on a dry lot with 2-3 flakes of hay each. (In effect, it's free choice hay while they're turned out, since it's usually fed in a hay net or multiple small piles, and they check on it through turnout.)
I went back and forth, but ultimately made the decision NOT to test the NSC levels of the hay he's eating right now, for a bunch of reasons: his ACTH levels were very low, he was handling the pergolide beautifully, and I didn't have a lot of options for an alternative supplier. If he really truly needed every speck of his diet controlled, I would test the hay and then go to either soaking it (really, really impractical and darn near impossible in Vermont in the winter) or buying my own low-NSC hay through a national distributor like Standlee. I strongly suspect this course is in our future, but for now I opted to change as few variables as possible and wait for his updated ACTH blood test before taking drastic measures. The barn has also tested batches of hay from this distributor in the past, and they've all come back low NSC, which gave me a measure of confidence that future batches would be as well. (Yes, I realize it can be different for each cutting, but this farmer has a history of consistency, which was enough for me for now.)
LOVE these guys.
Tristan is still on his customized supplement from HorseTech. The base is their High Point Grass/Mixed Hay supplement which is designed to basically fill in nutritional needs for a horse that's eating exclusively grass and/or hay. I worked with HorseTech to add a few things to it: I doubled the Vitamin E content up to 1,500 IU a day after quite a bit of research, in order to help support his muscle growth. I also added in 20mg of biotin a day, and HorseTech suggested bumping up the lysine and methione as well, all to support hoof growth as he continues to struggle a bit after his surgery.
Finally, his grain. The barn feeds Blue Seal feed, which is not my favorite but is perfectly fine. Pre-diagnosis, he was eating 1/2 quart AM + PM of their senior feed, Sentinel LS. Post-diagnosis, he initial went on the Performance LS but after checking in with the vet we switched him to the Carb Guard. He has been on that before and I knew he'd eat it up, even though it is more bland. Until last week, he was at 1 quart AM + PM (at 1.3lbs per quart, so 2.6lbs per day). After getting some opinions and finally talking to my friend J., we're bumping him up to 1.5 quarts AM + PM (so a total of 3.9lbs per day).
The last addition is something else designed to help him add a little bit of weight before winter comes. He's not skinny, but he is just a teensy bit ribbier than I want, especially headed into winter. I'm not a believer in really bulking a horse up to the point of obesity before winter, but knowing how he dropped weight last winter I want him to have a little more fat over his ribs. Right now, you can see his ribs just slightly when you look at him obliquely, and you can feel them if you press in.
So in addition to the Carb Guard, he's getting 1/4 quart of alfalfa pellets AM + PM. If I like the way he's adding weight on that, and if it does the impossible and adds some energy even better! We can always keep adding that over the winter, and he can get some at lunch as a snack in the winter if he needs. I chose pellets over cubes or straight up hay because it's easy to give with his grain, and the barn keeps it on hand already.
The biggest question area going forward is how to handle hay and grass going forward. For now, I haven't made any real changes other than being careful about turnout when the sugar content of the grass is high. However, it's perfectly possible that I will have to really re-examine his options going forward.
So, for now:
2 flakes hay AM + PM
1.5Q of Carb Guard AM + PM
1/4Q of alfalfa pellets AM + PM
1 scoop High Point Custom Blend AM + PM
grass turnout or free choice hay