What if the pasture is not too large? Suppose that you are having 10 hectares of land. That much land can support only 5-6 horses at the most. And even if you slaughter one horse every year, the meat won't be enough for more than 2 weeks (if your family is consisted of 4-5 members).
Yeah, you would need a large pasture for that. If I have just 10 hectares, I'd probably just farm grains and eat those directly rather than use those for animal feed. If I really need to sneak in some meat in my diet I'd probably go for rabbit. I heard they can be fed hay so maybe I can use the straw left after harvesting the grains.