If Dr. Karen Wolf needs another skilled set of hands for a tiger procedure, she knows who to call. And if Dr. Allison Case has a beaver or owl that needs attention while she’s out of town, she has a second clinic just a van-trip away. The two women are head veterinarians of Point Defiance Zoo & Aquarium and Northwest Trek Wildlife Park, respectively – and these sister zoos have veterinary teams with a long tradition of helping each other. “People don’t realize there’s this crossover,” explains Dr. Wolf of the unique veterinary partnership. “I have absolute confidence that if …