Answer by
traumatised (3285)
Could be several things, including:
Anal gland needs to be emptied of liquid/fecal buildup by you/the vet (who can show you how).
Constipation. You may need to change the food. And make sure the dog always has plenty of water.
Worms. If the dog is also bloated, lethargic, coughing or has diarrhea, get it tested.