Unhealthy dog ​​diet

If a dog eats too much salt or lacks vitamins, it will cause tear stains in the dog. Feed your dog's dog food with an appropriate amount of salt. If your dog consumes too much additional salt, it will cause tear stains. If the vitamin content in the dog's daily diet does not meet the needs, and the owner does not take additional supplements, tear stains will also occur.

Ear canal infection in dogs

Ear canal infection is a common cause of tear stains in dogs. When the ear canal is infected by bacteria, viruses, molds, parasites, or the ears are swollen, painful, or itchy, it will cause the dog to frequently scratch its ears with its hind feet. Because the pain deep in the ear canal will extend to around the eyes, it will also stimulate the secretion of lacrimal glands. When too many tears cannot be discharged from the nasolacrimal duct, they will overflow from the corners of the eyes near the nose. Over a long period of time, brown tear stains on your dog's coat will become very obvious.

Nasolacrimal duct obstruction in dogs

Nasolacrimal duct obstruction is caused by inflammation and swelling of the nasolacrimal duct due to infection, resulting in complete blockage or incomplete blockage of the entire duct. Tears cannot drain normally from the nasolacrimal duct and will naturally overflow, resulting in tear stains.

Entropion of dog eyelids

Entropion of eyelids is also called inverted eyelashes. Entropion of the eyelids will cause the eyelashes to continuously irritate the cornea. This situation will make the dog's eyes very uncomfortable, causing the dog to frequently scratch the eyes with its forelimbs. Therefore, it is often seen that dogs appear tearful, which can also cause very serious tear stains.

Dacryoadenitis in dogs

Dacryoadenitis is mainly an infection of the lacrimal glands that secrete tears, resulting in abnormal and large amounts of tear secretion. The nasolacrimal duct has no time to clear so many tears, which will cause the tears to flow out and form ugly tear stains over time.

Hereditary disease

Primary polytechophora is a hereditary disease in which tears are often secreted excessively, thus easily causing tear stains.