Question: My 22 year old gelding has ground down teeth, missing teeth. He can still graze on my pasture, but has a hard time chewing hay. He was losing weight. I started him on Purina Equine Senior several months ago and he's now a good weight, but I know he needs a supplement. There are some vitamins in the feed and I don't want to create a vitamin or mineral overload by adding the wrong supplement. I'm getting Uckele Equibase Grass for my senior mare. Would that be okay to feed my gelding as well? Dr. Kellon: If your horse's whole diet is Equine Senior you don't have to add anything else. If still eating hay/pasture, you need to supplement that. What does he weigh and  how much senior feed does he get? Question: Thanks for getting back to me.  He’s still eating pasture, but it’s by no means lush and, although I see him grazing, I don’t know how much grass he’s actually ingesting. I live in high elevation southwestern NM. Arid, gramma bunch grass and some other type grass – and lots of bare ground. 20-acre pasture. He’s a good weight now, has access to the pasture almost 24/7. I give him 2 pounds, 3xday of senior feed. I first soak it for 20-30 minutes in warm water so it’s soft. He gobbles it down. I soak his hay, and he does eat some of it, but there are always wads of partially chewed hay around his feed tub. Although he looks and seems healthy, I doubt he’s getting optimum nutrition. As stated earlier, though, I don’t want to over supplement  him. He’s an Arabian, 14.2 hands, about 750 pounds. He was starved by a previous owner and I think he must have been eating sticks. Many of his teeth were ground down almost to nubs. My vet checks his teeth regularly. Dr. Kellon: I calculate he's still getting about 37.5% of his calories from pasture and/or hay, certainly enough to warrant a supplement! When your grasses go dormant the protein drops, as well as vitamins and often minerals. I would suggest 5 oz/day of Milk and Grow.