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other disease Dog, Cat

Cataract

Cataract is an opacification of the lens, the eye's natural lens, which prevents light from properly reaching the retina. It affects dogs, cats, and horses and can be partial or total, in one or both eyes. It gradually causes vision loss, p...

What is it?

Cataract is an opacification of the lens, the eye's natural lens, which prevents light from properly reaching the retina. It affects dogs, cats, and horses and can be partial or total, in one or both eyes. It gradually causes vision loss, potentially leading to blindness if left unmanaged.

Cataract can be hereditary in certain dog breeds, appear with aging, or result from diabetes mellitus, particularly in dogs. It can also occur after eye trauma, internal eye inflammation, or certain abnormalities present from birth. In horses, it can be congenital or linked to chronic eye inflammation.

Advanced age, certain genetically predisposed dog breeds, diabetes mellitus, and a history of eye trauma increase the risk of cataract. Chronic eye inflammation or prolonged exposure to certain environmental factors can also promote its development.

Commonly observed signs

These signs are neither exhaustive nor specific. Only a veterinarian can establish a diagnosis.

A whitish or bluish haze is often visible over the pupil when looking closely at the eye. The animal may seem hesitant to move around, bump into objects, or have difficulty judging distances, especially in low light. Eye discomfort, tearing, or an abnormal-looking pupil may also accompany this condition.

When to consult without delay

This list does not replace veterinary advice. It gathers situations that justify a prompt consultation.

Transmission

Cataract is not a contagious disease and is not transmitted between animals or to humans. Only the genetic predisposition can be passed from parents to 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.

1

If you notice a change in the appearance or behavior related to your pet's eyes, it is important to consult a veterinarian promptly for a thorough examination. Only a professional can assess the situation and suggest appropriate management. Never attempt eye self-medication without veterinary advice.

Prevention

Regular veterinary check-ups help detect early signs of cataract, especially in predisposed breeds or diabetic animals. Good diabetes control and protecting the eye from trauma help reduce the risk. There is no guaranteed way to prevent hereditary or age-related forms.

References

MSD Veterinary Manual

Content reviewed by the TunisieVet editorial team · Updated 08 August 2026

AT A GLANCE

AgentOther
SpeciesDog, Cat
VaccineNo
Transmissible to humansNo

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Affected species

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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