The reasons why dogs have more eye mucus:

1. It may be viral infection, such as canine distemper virus, which will increase the amount of eye discharge in dogs.

2. It may be that the nasolacrimal duct is blocked, especially for dogs with short noses. The nasolacrimal duct is blocked and eye secretions can only flow out through the corners of the eyes and accumulate into eye feces.

3. It may be caused by eye inflammation, such as conjunctivitis, blepharitis, eyelid entropion, etc., and excessive tearing may lead to excessive eye feces.

4. It may be that eating high-sugar and high-salt foods or a large amount of animal offal causes the dog to shed more tears and form eye feces.

5. It is also possible that there is trichiasis or foreign objects in the eyes, causing the eyes to shed too many tears and form eye feces.