Hi Debby. A lot of the breeds (especially the hounds) have this very common problem often. Clean his/her eye with a clean/sterile cotton wad soaked in warm water twice a day. You may also use regular saline solution like you use for contact lenses. Do not rub the eye, but wipe it clean softly. Sometimes the eye just gets irritated and it's no major deal. However, if the secretion (pus) continues for more than a few days, I would suggest you consult your vet. She/he might need antibiotic drops. Hope this helps.
It is probably some kind of infection of the eye or tear duct. Take your dog to the vet for treatment.
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