Join Date: Aug 2009
Location: secret mountain valley
get a new vet. There are sometimes physical reasons and sometimes biochemical reasons. We have worked with a few stallions with this problem and have had a lot of success, depending on the problem. There are some drugs you can give to help with libido, but they are only used after a full work up to determine the cause of his problems. There is also sometimes a fairly complicated protocol for it so you may want to consider how valuable he is as a breeder before sinking a lot of money in for the diagnosis.
Is this a recurring problem or was it a one time issue? I'd suggest finding a vet with repro experience (as in did an internship, etc. with a theriogenologist). You can go to the Society for Theriogenology website to look for board certified practicioners in your area who may be able to help! Good luck!