Collies & aussies have a hard time with ivermectin. I think it passes the blood brain barrier and collects in their brain & causes neurological problems. I've been reading a little bit about it this week. Because I just got a new puppy and he came with worms. And he's 1/2 australian shepherd.

Collies & aussies have a hard time with ivermectin. I think it passes the blood brain barrier and collects in their brain in causes and neurological problems. I've been reading a little bit about it this week. Because I just got a new puppy and he came with worms. And he's 1/2 australian shepherd.