Weight Gain vs Heat

Question
Good morning...about 5 weeks ago now you answered a question of mine on safe weight gain for a newly purchased mildly underweight Thoroughbred that stands 16.2 and just turned 7 this past Wednesday (7 March).  Using your great suggestions :), I placed the horse on a pre and probiotic (SmartDigest Ultra), have him on 2 quarts of Horsemen's Edge 100, 2 quarts textured feed and 3 cups of rice bran pellets...all twice daily.  Besides the pre and probiotic he is also getting a coat and hoof supplement (Grand Complete) and a muscle support supplement (SmartMuscle Mass) which I will stop in another month or so as he is muscling up nicely with the ongoing work.  He is doing fantastic on all this but I am running into the other little issue that since he IS feeling so good right now, he is getting hot even with steady work and all day turnout.  I don't want to drop the feed just yet as we have just a little more weight to go to get him to optimum.  I can increase the rice bran easily enough to get up the max 8 cups/day but I need to see if there is something else I can use/substitute to try and keep his level of "heat" under control..I don't want him to get any hotter.  Someone suggested reducing the textured grain by a quart each feeding and adding Cool Calories 100 instead.  Thoughts?

Answer
Hi Terese,

Its good to hear that your gelding is doing well and gaining the weight/condition that he needed.  The suggestion you were given to switch him from a textured (starch based) feed to a fat/fiber based feed is a good one given his change in attitude.  Some horses don't handle starch diets very well and can really start to 'feel their oats', so to speak.  Thoroughbreds especially seem to be sensitive to too much starch in the diet.  A performance formulated fat/fiber feed will be able to support his weight and muscle gain and his work schedule...but avoid the 'maintenance' formulated fat/fiber feeds as they may not provide enough energy to keep your horse on the right track for weight gain.  So if you're feeding Purina products, try the Ultium Competition.  You can continue with the rice bran without issue, phase out the hoof supplement and muscle support supplement as you've suggested, and remain on the prebiotic.  You can consider dis-continuing the prebiotic once your horse has reached the goal weight/condition you are looking for...but there's no harm in continuing with the product if you choose to.  If you take him off the SmartDigest and notice he starts losing weight, it's a sign that he's one of those horses that needs a prebiotic in the diet all the time.  

Keep up the good work.

Thanks, Corlena