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Cataract
Cataract is a clouding of the crystalline lens, the natural lens of the eye, which prevents light from reaching the retina. It affects dogs, cats and horses and can be partial or total, in one or both eyes. It gradually leads to a decline i...
What is it?
Cataract is a clouding of the crystalline lens, the natural lens of the eye, which prevents light from reaching the retina. It affects dogs, cats and horses and can be partial or total, in one or both eyes. It gradually leads to a decline in vision, which can lead to blindness if it is not treated.
Commonly observed signs
These signs are neither exhaustive nor specific. Only a veterinarian can establish a diagnosis.
Related signs — each one links to its page:
We often observe a whitish or bluish veil at the level of the pupil, clearly visible when looking at the eye closely. The animal may appear hesitant to move, bump into objects, or have difficulty judging distances, especially in the dark. Eye discomfort, watery eyes or an abnormal pupil can also accompany this disorder.
When to consult without delay
This list does not replace veterinary advice. It gathers situations that justify a prompt consultation.
Causes and risk factors
Cataract can be hereditary in certain breeds of dogs, appear with age, or result from diabetes mellitus, particularly in dogs. It can also occur after eye trauma, internal inflammation of the eye or certain abnormalities present from birth. In horses, it can be congenital or linked to chronic ocular inflammation.
Older age, certain genetically predisposed dog breeds, diabetes mellitus, and history of eye trauma increase the risk of Cataract. Chronic eye inflammation or prolonged exposure to certain environmental factors can also contribute to its appearance.
Transmission
Cataract is not a contagious disease and is not transmitted from animal to animal or to humans. Only genetic predisposition can be transmitted from parents to their offspring in certain breeds.
Diagnosis and care
Diagnosis is the veterinarian's responsibility, based on clinical examination and laboratory tests. Care is decided case by case.
If you notice a change in the appearance or behavior of your pet's eyes, it is important to see a veterinarian quickly for a thorough examination. Only a professional can assess the situation and offer appropriate support. Never attempt eye self-medication without veterinary advice.
Prevention
Regular veterinary monitoring allows signs of Cataract to be detected early, especially in predisposed breeds or diabetic animals. Good diabetes control and protection of the eye from trauma help reduce the risk. There is no guaranteed way to prevent hereditary or age-related forms.
References
Content reviewed by the TunisieVet editorial team · Updated 10 August 2026
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This information is provided for educational purposes only and is not a substitute for a veterinary consultation. If you have any concerns about your animal's health, consult a veterinarian.
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