Some general comments about feeding-amounts, kinds, set-up, etc.-seem in order.
It is ALWAYS best to feed each horse separately; that is the ONLY way to know exactly what an individual horse's food intake is, and to control what/how much they get-especially important when there are weight/physical condition issues.
Every horse is INDEED an individual; NO blanket statements can really be made about how much to feed, according to height and other parameters! I think it is a mistake to 'insist' to someone that their horse 'simply must'(to paraphrase)be given a certain number of cups of concentrate/day.(And yes, though the measuring cup is a convenient unit to use in doling out concentrates to miniatures, it IS important to know how much that WEIGHS-and the ultimate decider of what is 'correct' for an individual horse is the horse's condition.)
I am continuously amazed at how often what is to me an astonishingly large amount of concentrated feed is insisted upon...now, if feeding ONLY one of the "complete" pelleted feeds, this might make sense(though I personally would never rely completely upon such a formulation, as I STRONGLY believe in the importance of good hay, or grazing,at all times). I am in the process of moving my concentrate program over pretty much to Purina Senior for EVERYONE, based upon research and personal observation. I have a 23 yr old, 34" mare who looks GREAT on 1 cup(which weighs at @ 1/4 lb.), twice daily, of Senior, along with prime alfalfa, and good grass(brome/orchard/timothy), proportioned, for her, at about half and half. My 38", QH-build(I DON'T mean 'drafty'!) R "Over"mare is thriving on only about 1 1/4 cup(about 1/3 lb.,total),AM & PM,of a mix-whole oats, BOSS, Mare and Maintenance ration balancer-twice daily, but I am in the process of changing her gradually over to Senior only(as her concentrate-Purina Senior can indeed be fed as the 'only'ration, but can also be fed in conjunction with hay); will probably end up giving her about the same weight of that-plus, she gets about 1/4-1/3 alfalfa to 2/3-3/4 grass. My others all get the same mix, but -I have not seen any real ongoing benefit from the BOSS, along with having some concerns about recent research that indicates that there "might"sometimes be colic problems associated with its use-so am giving it up when I run out of my currrent supply. I really want to simplify my feed program, and the prep of same, so will gradually be changing over to the Senior(and probably some of the Mare and Maintenance),as fits their individual situations-I have one gelding who only gets a tiny handful of alfalfa, and will get a minimum of the Senior(if ANY!), plus Mare and Maintenance, based on his hay intake-as he gets hefty just looking at feed-while others will get different, varying proportions. Even my 15 hand, approx. 950-1000 lb. APHA mare only gets 1 2/3 cups of Senior, plus 1/3 cup corn oil(to aid in ulcer prevention), AM and PM, plus @ 2 lbs. of alfalfa, and 5-5 12 lb. grass hay-and she is in good flesh and excellent health!)Edited to add: I very much support the use of moderate amounts of quality alfalfa, for both nutritional rounding-out, AND for picking up/maintaining condition!)
If ANY horse is not thriving as you feel it should, ALL possible causes should be considered and addressed--possible tooth problems, possible parasite load, any other possible health issues-along with individual feeding and observation, and only GRADUAL changes in a feeding program, whether it be changes in either type OR amount.
