Canine glaucoma old. These types of glaucoma are due to abnormalities in the structures of the eye which occurred during ocular development. One or both eyes may be affected. Primary glaucomas occur in the absence of other eye disease, and are therefore presumed to be genetic in origin. The most common type of glaucoma in dogs is primary angle-closure glaucoma (PACG). The least common type of glaucoma in dogs is primary open-angle glaucoma (POAG), although this is the most common type that affects humans. In the Beagle, POAG is an inherited autosomal recessive trait. Secondary glaucomas occur when other eye diseases alter
Supernumerary body part Supernumerary body part Supernumerary body parts are most commonly a congenital disorder involving the growth of an additional part of the body and a deviation from the body plan. Body parts may be easily visible or hidden away, such as internal organs. Many additional body parts form by the same process as conjoined twins: the zygote begins to split but fails to completely separate. This condition may also be a symptom of repeated occurrences of continuous inbreeding in a genetic line. Specific types of additional body parts include: Vestigial structures are anatomical structures of organisms in a species which are