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G-Tract or Immune: Which One Fits Your Horse?
G-Tract and Immune share Turkey Tail, Lion’s Mane, live yeast and colostrum. Here’s how the two ImmuBiome formulas differ and which suits your horse.
- 4.93 from 5,590 reviews
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Read the two labels side by side and you’d be forgiven for thinking they’re the same tub. G-Tract and Immune share the same mushrooms, the same live yeasts, the same colostrum and the same eight probiotic strains. Where they part ways is the job each was built for, and that’s what should decide it.
Side by side
| What | G-Tract | Immune |
|---|---|---|
| Built for | Normal digestion, stomach to hindgut | Natural defenses and overall resilience |
| Mushrooms | Turkey Tail, Lion’s Mane | Turkey Tail, Lion’s Mane |
| Live yeast | Saccharomyces, 25 billion CFU on the label | Same Saccharomyces yeasts listed (no CFU given) |
| Colostrum | 1,500 mg | 1,500 mg |
| Probiotics | 3 billion CFU | 3 billion CFU |
| Prebiotics | 5,500 mg | 8,000 mg |
| Beta-glucans | 25% minimum | 25% minimum |
Choose G-Tract when digestion is the worry
If your horse’s manure changes with every hay delivery, he goes off his feed when he travels, or he’s in hard training and you want to look after his stomach and hindgut, start with G-Tract. It’s the formula behind our ulcer protocol and the lead formula in Hindgut & Ulcer Support.
Choose Immune when his defenses are working overtime
A horse on the show circuit, a horse who’s just moved barns, a youngster meeting a new herd, or an older horse heading into winter: that’s Immune territory. It carries more prebiotic fiber than G-Tract (8,000 mg against 5,500 mg) and is built around supporting a balanced immune system from the gut out. It leads our Immune Support collection.
What about both?
Because they share so much, most horses only need one. If you’re torn, think about which problem shows up first in your horse. If it’s his gut, G-Tract. If it’s every bug going around the barn, Immune. Our gut health page explains why the two jobs overlap so much.
Still deciding? Try the Formula Finder or see every tub size on Compare Formulas.
Questions owners ask
Are G-Tract and Immune the same formula?
No, though they’re close. They share Turkey Tail, Lion’s Mane, Saccharomyces yeasts, 1,500 mg of colostrum and 3 billion CFU of probiotics. G-Tract is built for digestion and lists 25 billion CFU of live yeast, while Immune carries more prebiotics and is built for natural defenses.
Can I feed G-Tract and Immune together?
Some owners do, but with so much overlap most horses only need one. If you’d like to combine them, call us at 1-888-31-HORSE or check with your vet so the plan makes sense as a whole.
Which is better for a horse who travels a lot?
It depends on what travel does to him. If his manure or appetite changes on the road, start with G-Tract. If he tends to pick up whatever is going around at shows, start with Immune.
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Shop G-Tract and Immune
Every formula ships free on subscription, and you can return any tub within 30 days, even opened.
G-Tract
4.93 (777)
From $69
Everyday digestive support from the stomach to the hindgut, with 25 billion CFU of live yeast.
Immune
4.94 (529)
From $69
Everyday support for natural defenses through travel, shows and seasonal change.
These statements are about nutritional support only. ImmuBiome supplements are not drugs and don't take the place of veterinary care. Talk with your veterinarian about your horse's specific needs.
