Which of the following is NOT a cause of conjunctivitis in cats?

Feline diabetes is primarily a metabolic disorder characterized by the inability of the body to produce or properly use insulin, leading to elevated blood sugar levels. It is not directly associated with conjunctivitis, which is an inflammation of the conjunctiva in the eye.

In contrast, Chlamydia, Calicivirus, and Feline herpesvirus are known infectious agents that can lead to conjunctivitis in cats. Chlamydia psittaci often causes conjunctivitis as part of a broader infection. Calicivirus can lead to respiratory ailments, and conjunctivitis is a common secondary condition due to the inflammation of the upper respiratory tract. Feline herpesvirus is particularly notorious for causing conjunctivitis because it can lead to severe ocular manifestations, including keratitis and conjunctival inflammation.

Thus, recognizing feline diabetes as unrelated to conjunctivitis highlights the importance of differentiating between systemic diseases and localized infections when assessing ocular conditions in cats.