Walking the family dog could do more harm than good especially if the dog has a condition such as glaucoma or weak or thin corneas. Pressure created by neck collars significantly increases interocular pressure, which may lead to severe eye damage and vision loss in pets with ocular conditions, according to a study published in the Journal of the American Animal Hospital Association (Denver).

In dogs with some types of ocular disease, such as glaucoma, even brief increases in interocular pressure could have a detrimental effect on the eye, resulting in further damage to the optic nerve and retina.Based on our study findings, it is highly recommended that harnesses, rather than neck collars, be used in dogs with glaucoma.

Many general practitioners are not aware of the anecdotal evidence that collars significantly increase interocular pressure.

We hope that results of this study will prompt them to routinely recommend harnesses for patients with certain ocular conditions.

Of particular interest, the study showed that dogs bred to pull objects, such as the Alaskan malamute and Siberian husky, may be somewhat resistant to an increase in interocular pressure.

Pulling when being walked on a leash may be more than just an annoying behavior, it may have a detrimental impact on a dog's health, since the longterm risks of transient interocular pressure increases associated with ocular disease are not fully understood, any pet that tends to pull while being walked on a leash may benefit from use of a harness rather than a collar.