We took our dog to the Vet today. She has been loaing weight no matter how much we feed her. She had her blood work done and got a full check up. She is a happy dog almost 13 yrs old now. We would like to have her gain a bit more weight she is only at 58 lbs. She lost 10 lbs in the last few months. The vet told us to feed her something with more calories. I just wanted to know what would be a good product to use to help her gain a bit more weight an muscle.