Allergies, infections, hairs, blocked tear ducts and yeast are reasons dogs eyes can get gunky or stained. The author explains the reddish stains are caused by iron released from the breakdown of red blood cells which becomes part of a pigment-containing molecule called porphyrin. Porphyrin is in dogs’ tears and causes the actual staining.
The author shares a few tips to keep eyes clean and less stained.
Source: Happy Puppy Tips, June 2022. Link.
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