Has this happened to anyone else ? I have a 10 month old red merel australian shepherd that i had neutered at 5 months. I got him at 3 months and he was a happy, loveable puppy. It seems the neuter brought out aggressive/anxious tendencies in him. Hes loveable to me and my boyfriend, but sometimes he does a quick nip at people he doesn't see daily. For instance, he's spent time with my dad every few weeks since I got him, but when my dad walks in the door he still acts unsure of nervous (barking, growling, even nipping). Also, when I bring him to the dog park, he mostly plays nice but will nip at other dogs from time to time in an aggressive manner. It's almost like a response to anxiety or being unsure. He has also expressed submissive tendencies (peeing when hes in trouble, putting ears down, avoiding eye contact). All of these behaviors started post-neuter. Hes such a sweet boy, I want him to have the happy life he deserves. I'm just not sure what more I can do for him. His vet put him on anti anxiety meds that we tried for months with no avail. Hes well exsersized and is shown lots of love. Any ideas ?