Thanks to my buddy Steve for this. He says:
just drove past some mini yaks. I will get details.
this is not from the farm I passed but still totally amazing.
I am always down with service animals. We've had about a jillion service mini ponies here on PSAMP, but I can honestly say this is the first service yak I have ever seen or heard of. Some humor blog should start up about sports and mini yaks. I mean come on.