I have used Purina Equine Senior for over 20 years with no problems. In fact, my oldest horse died of natural causes at the age of 42. I have a 26 year old black thoroughbred mare that had been losing weight, even though she had her teeth floated recently and was on Equine Senior. I have been out of state for 8 months and the caretaker took the mare to an equine dentist and had her teeth floated aagain. The previous floatation was done by a regular vet and apparently not done very well. The caretaker's