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Weight Builder

Farnam Companies, Inc. — Item #10816
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Adds calories without extra grain

  • Provides extra calories from fat for weight gain & a healthy body condition
  • Contains over twice the calories found in an equal amount of grain
Farnam’s Weight Builder provides extra calories for weight gain and to fuel performance. Weight Builder contains 40% fat, is high in omega 3 fatty acids, and has added calcium to help maintain calcium/phosphorus ratio.


Learn More about Weight Builder

View our Weight Gain Supplement Comparison Chart


Guaranteed Analysis per serving:
(Maintenance Dose = 2 scoops (4 oz) daily)
  • Crude Protein (min)
  • Crude Fat (min)
  • Omega 3 fatty acid (min)
  • Crude Fiber (max)
  • Calcium (min)
  • Calcium (max)
  • Phosphorus
Ingredients:: Maize distiller’s grains with solubles dehydrated, heat stabilized flax meal, calcium carbonate, partially hydrogenated vegetable fat, propionic acid, mixed tocopherols (a natural preservative), BHT/BHA (as a preservative), artificial flavor.


Instructions for Use:
Feeding Instructions: Enclosed scoop holds 2 ounces.

To enhance skin coat and condition, feed one scoop (2 ounces) daily with regular grain ration.

For added calories, feed 2 scoops (4 ounces) daily with regular grain ration.

Depending on a horse's activity level and condition, up to 8 oz of Weight Builder may be fed with no adverse effects.
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    out of 5
    89% of customers would recommend this product to a friend!
    Tell us what you think!

    The reviews provided on this website represent the experience of the individual posting the review. We do not adopt, edit, or endorse any of the submissions posted within the reviews section. Rather, the reviews are part of an online community of animal owners that desire to share their particular experience with other individuals. These reviews are not a substitute for discussing the health of your animal with a veterinarian.

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    Weight Builder is rated 4.7 out of 5 by 83.
    Rated 5 out of 5 by from Perfect for my underweight hard keeper When I obtained my horse he was grossly underweight and proved to be a hard keeper, nothing I did produced any type of weight gain results on him. I finally added this to his smart paks and like Magic, he was a different horse. I keep him on a maintenance dose now rather than a weight building dose and I've not had an issue with him losing weight or struggling to keep what he's put on. The picture speaks for itself!! This stuff REALLY works. Notable as well, he's prone to being a wild thing, this stuff doesn't add to his sassiness under saddle.
    Date published: 2017-09-14
    Rated 5 out of 5 by from Awesome! Weight Builder has helped get the weight back on my rescued mare. It's working awesome!
    Date published: 2017-09-10
    Rated 5 out of 5 by from Works great and fast! My 23yo retired eventer was rapidly losing weight and I was getting really worried. I put him on this weight builder and added beer pulp to his diet and in a weight he's already looking so much better. He has a nice layer of fat on his body again and the shine has returned to his coat. Very pleased with how this supplement works. He's high strung but the added calories are not making him an "hotter". It's bringing much peace of mind with winter coming.
    Date published: 2017-08-20
    Rated 5 out of 5 by from Great Stuff We rescued a kill pen horse that was around 250lbs under weight. Beautiful guy, just needed a little help packing on a few more pounds. With appropriate nutrition and the added help of weight builder he has gained about 200lbs in a month. I am sure over time the proper nutrition would have gotten the horse to where he needed to be, but this certainly sped up the process by a few months. Once he is to his ideal weight we will drop him down to a maintenance dose. Weight Builder is great stuff.
    Date published: 2017-07-26
    Rated 5 out of 5 by from my horse loves it! I bought this 2 months ago hoping to put some weight on my TB since he tends to lose a bunch of weight in summer. I used this with grain and sweet feed and he absolutely loved it and one day I didn't have grain so it was just sweet feed and the smartpak and he didn't care!! SO PICKY EATER APPROVED :) overtime I noticed he started gaining his stomach back and with the amount of work him and I do we use a full strip and he's heathly and nice and chunky !!!
    Date published: 2017-05-07
    Rated 5 out of 5 by from Works great! Have tried many products to keep weight on my two thoroughbreds. Farnam's Weight Builder has given me the best results.
    Date published: 2017-03-10
    Rated 5 out of 5 by from I think it's working! My gelding needs to put on weight and I think this is helping.
    Date published: 2017-01-19
    Rated 5 out of 5 by from Love it!! I have been using this for about 30 days now and am already seeing a difference in our retired 28 year old mare. This was a life saver! We tried all the tricks in the book and this seems to be working. Building and holding weight and also boosting her coat. Highly reccomended.
    Date published: 2016-11-12
    Rated 5 out of 5 by from Not a cure all but... I started my aged hard keeper on this about 3 mo ago after injury brought on rapid weight loss. We we're going to put her down but this was my hail Mary. Its a slow gain. It takes times... but it really does help. Very palatable. This product saved my old girls life and just gave her a boost. She's really starting to bloom.
    Date published: 2016-04-27
    Rated 5 out of 5 by from works effectively! I have a barrle horse that has dropped weight as we work towords be a competitive athletes I researched and found the at a great price, i have been using this product for only 10 days and I can visually tell my mare has been filling out beautifully so happy I bought this!
    Date published: 2016-02-29
    Rated 5 out of 5 by from Only weight supplement with real results I have a very active AQHA gelding who is 12 yrs old. He's a very hard keeper and with our busy show season/cold winter months, he has always been on the skinny side. I've fed him countless supplements for weight, even put him on a strict worming schedule and nothing else has worked. With this product i saw results within less than a month. Several people at my barn feed this product and they all love it. It smells great and mixes with feed very well. My picky eater will actually take it out of my hand.
    Date published: 2016-02-22
    Rated 4 out of 5 by from Missing scoop! I love the product so far, I think it's going to be really good for my horse. The only complaint I have is that the scoop was not included.
    Date published: 2016-01-12
    Rated 4 out of 5 by from Shinny coat and weight gain I have a hard to keep OTTB who actually put weight on this winter while on this product!
    Date published: 2015-06-23
    Rated 5 out of 5 by from Works Great I have been using this for 2 years now. I am able to maintain and/or add weight if needed. It also makes our boys ( 2 Belgian Drafts) coats look great!
    Date published: 2015-05-14
    Rated 5 out of 5 by from Puts weight on fast I bought this for my thin OTTB gelding. Saw I provement in the first 2 weeks!
    Date published: 2015-03-29
    Rated 5 out of 5 by from Great product for hard keepers! This is my 14 yo OTTB, a hard keeper. This time last year, he had dropped weight rapidly after moving barns. I placed him on Weight Builder with vast improvement after a couple months. He didn't require it at all over the summer. I put him back on it this winter to head off weight loss. What a difference compared to last January! I highly recommend this product for hard keepers. You won't be disappointed.
    Date published: 2015-01-17
    Rated 5 out of 5 by from Good Product Started using this product 2 months ago. My horse has filled out his topline and maintained his weight going into Winter.
    Date published: 2014-12-31
    Rated 5 out of 5 by from works wonders My horse loses weight every winter. 5 years ago I came across weight builder & haven't had a problem since. I have found that mixing it with a little wheat bran & water then adding it to his grain works best. It is worth the extra expense. As the saying goes you get what you pay for!
    Date published: 2014-10-09
    Rated 5 out of 5 by from I can see a little difference in his weight. He's looking better. I might have to leave him on it all winter with the way people are talking about how harsh it will be.
    Date published: 2014-09-10
    Rated 5 out of 5 by from So far, so good! We had a hard winter here, and a few of my horses lost a considerable amount of weight. We started with increased grain and hay (a lot of extra hay), but didn't get the results we needed. I didn't want to keep increasing the grain and they wouldn't eat any more hay (started wasting it) so we decided to find an alternative way of adding calories. I've only had my horses on it for about 2 weeks, but the skinniest has definitely had a considerable amount of weight gain. He is on 4 of the included scoops, which is the maximum the manufacturer recommends. Another of our boys who wasn't as bad is on 3 scoops and I am already thinking of cutting him down as he has filled out pretty well. The third of my guys has yet to show any improvement, but it has been a very short period of time and I am surprised I have already seen the results I got in the other two! I also placed one of my geldings who had no weight issues but needs a little extra shine to his coat. We have not seen any results in that regard yet, but, I don't think it has even had time to make an impact and I will continue it to see what happens. All of these horses LOVE this stuff. Two are not picky, the other two have turned down supplements in the past. If I forget to give it to them during feeding time and throw it in their bucket after they already finished their grain, they actually lick their bowl clean to get the stuff all by itself. Overall, very satisfied so far.
    Date published: 2014-05-22
    Rated 5 out of 5 by from wonderful product My horse who is 17 had a very hard winter as did we all. He had lost weight his coat was dull as was he. I used weightbuilder and in one month he had a shinier coat and started filling out. The barn owner was sceptical but was so impressed that we are now giving to all the horses in the barn. He calls it giving fat.
    Date published: 2014-05-14
    Rated 1 out of 5 by from Horse Wouldn't Touch It My horse refused to touch this or the grain that it was all over! Only reason I'm giving it a 1 star.
    Date published: 2014-04-29
    Rated 5 out of 5 by from Old Guy Weight My horse will drop some weight at the end of winter but this product seems to help keep it on.  Hopefully we will have a successful year again
    Date published: 2013-12-05
    Rated 4 out of 5 by from Really Works I have had my horse on this for 1 mo now. My horse dropped weight during his last move and I have tried a few other products which didn't seem to help. He is a 19 year old TB and is hard to keep his weight up. I can see he is filling out on his rump where the weight lose seemed to be most noticable. I recommend this product if you have a hard keeper.
    Date published: 2013-06-21
    Rated 5 out of 5 by from great weight gain supplement I have a 30 year old mare I have tried everything on this works like a charm! I highly recommend it!
    Date published: 2013-03-14
    Rated 5 out of 5 by from Best and Cheapest Weight Product Love this product because it's ease of use and palatability. All of my horses eat and love it. I've heard of other horses that don't eat it, but I've never had that problem. Put weight nicely on my thoroughbreds off the track and on my young horse who couldn't have a lot of grain because of an OCD worry. Love this product and recommend it to anyone.
    Date published: 2013-03-04
    Rated 5 out of 5 by from Works wonders I've had my OTTB, Blue now for just over 5 months and he has been on weight builder for the last 2 or so and it has worked wonders. He has filled out nicely and has a beautiful coat to boot. Now if you made such a product for my boxer, Daisy. And for the last month I have used the SmartPak system and it has really made doing supplements 10x easier.
    Date published: 2012-08-03
    Rated 5 out of 5 by from My horse is gaining so much weight My Thoroughbred gelding has always had a hard time gaining and maintaing his weight. Well this winter he looke really skinny his ribs were kind of showing. So I had the vet come out and float his teeth, and wormed him with Safeguard Power dose. But Finn still was gaining enough weight. So I read some of the reviews for Weight Builder and I thought I should give it a try. I a coulple of weeks Finn started putting on lots of weight his ribs were coverd and his topline was starting to fill in. Plus his coat is so shiny. When I started Finn on Wieght builder I weight him he was 1,110 on 11/23/11. I reweighed him on 12/20/11 and he was 1,146 he gained 36 pounds in 30 days. I have to reweigh him agian but from just looking at him he looks like he might be close to 1,200 pounds. Finn loves the taste of Weight Builder and he licks his food bucket clean, I have had to cut him back to on scoop a day because, I don't want him to get to fat.
    Date published: 2012-02-28
    Rated 5 out of 5 by from great weight everywhere! my gelding has a reallly hard time keeping weight in the winter, I started him on this and after 2-3 weeks I saw a great improvment, and it didnt seam to make him as hot as other weight supplememts have in the past. great stuff! plus, he darked up alot!!!
    Date published: 2012-02-22
    Rated 4 out of 5 by from Weight builder Finally found something this horse didn't turn the bucket upside down and eat it all up with gusto.. Thanks for the samples so we found one that worked for him, He is so PICKY!!
    Date published: 2012-01-18
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