Any tips on breaking a tree fighter?

Has anyone ever used the Farnam Weight Builder for horses on your dogs. During the running season I have trouble keeping weight on the dogs and I was thinking about trying this product, what do yall think? Feed back is appreciated.
Thanks!

There is no best breed. Each breed has their qualities good and bad. Any breed can be great and any breed can fail. Cold nosed refers to a dog that has a strong nose and can take an old (cold) track.