It should be - it is high in protein and the oil high in calories. Protein is good for building muscle. What are you feeding now? It would be better than mollichaff or hifi.
He's on chaff (not sure what type.....I've just been told chaff!) some form of conditioning nuts and sugar beet. I'll give it a go and swap the chaff for A A Oil
I struggle to keep weight on him once he's in hard work and by mid season I find he runs up very lean (he's a polocrosse pony by the way), fingers crossed this stuff help's do the trick, haven't know anybody who has used alfa a oil so have never heard anything back about it.
Use it on my TB all year round, will be bringing him back into work again soon and start using calm and condition again, the combination works really well for him.
definitely, our hunters get that, with full fat soya, baileys lo-cal and speedibeet it's fab for keeping condition on without making them too excitable.