We have a pekin with a swollen foot, it's got a low-grade infection (I know because it's hot). There's a swollen red blister on the right hand side and the middle toe is doubled in size. She is limping and has been limping for a few weeks now. I have tried washing her and doing some general first aid to clean the area but it is not getting better. We've been keeping her inside the duck house during the day with food and water so that she doesn't stress the area too much (she will try to keep up with the crew otherwise and it is a struggle). Another farmer friend gave us some antibiotics to try (Oxytetracycline). They have dairy goats not ducks so we don't know the dosage or how best to treat. Looking for advice -- will post photos below!
