Chasing Their Tail
Tail-chasing is usually just a sign of playfulness, but keep an eye out if your dog starts doing it too often. It could indicate a health or behavioral issue; for example, if your dog chews on his tail when he catches it, he may have skin allergies or anal glands that need to be emptied at the vet. If your dog starts chasing its tail obsessively, it could be an indication of OCD. Yes, this also affects animals. To be safe, check with your veterinarian.

Chasing Their Tail
Eating Poop
Yes, dogs can do this occasionally. It is really filthy, but not uncommon. When a dog begins eating its own or other dogs’ feces (also known as coprophagia), it usually indicates one of two things: either it is a behavior that can be addressed by training, or it is an indication of starvation. If your dog begins to do this on a regular basis, you should take it to the veterinarian. If your veterinarian rules out a vitamin shortage or a medical reason, it’s time to consult a trainer to help your dog overcome the habit.

Eating Poop