Tag Archives: Saint Bernards

The Globe And Orbit

Congenital Abnormalities Microphthalmos. Failure of the eye to develop to normal size is referred to as microphthalmos. Complete absence of the eye (anophthalmos) is extremely unusual in puppies and kittens. Microphthalmos is characterized by varying degrees of enophthalmos, with or without other ocular defects. Microphthalmos with multiple colobomas is an autosomal recessive trait linked to coat color in the Australian shepherd. In addition to small globes, affected dogs may have persistent pupillary membranes, cataract, equatorial staphylomas, choroidal hypoplasia, retinal dysplasia and detachment, and optic nerve hypoplasia. Vision is frequently impaired. Other breeds in which multiple ocular defects have been associated with coat color include the Great Dane, collie, Shetland sheepdog, and dachshund. Microphthalmos is also associated with inherited congenital cataracts in the miniature schnauzer, Old English sheepdog, Akita, and King Charles Cavalier spaniel. Microphthalmos occurs with retinal dysplasia in BedlingtonĀ terriers, Sealyham terriers, beagles, Labrador retrievers, and Doberman pinschers. Administration of griseofulvin to pregnant cats may produce microphthalmos in their offspring. Atypical Eye Position. Read more […]

The Cornea

Congenital Abnormalities Comeal Opacities. The cornea of the newborn puppy or kitten is a light blue color; or at least the cornea is less clear than that of the adult. In 2 to 4 weeks, corneal clearing is sufficient to permit ophthalmoscopic examination. It is not unusual to observe multifocal or diffuse faint white opacities in the corneas of young puppies and kittens. The opacities represent superficial foci of edema, and most are self-limiting. The cause of these opacities is unknown. Therapy is not necessary unless the opacities are accompanied by a mucopurulent discharge, in which case topical ophthalmic antimicrobial preparations may be applied. Animals born with their eyelids open often have diffuse corneal edema that clears in 14 to 18 days. Because reflex lacrimation is absent at birth, the exposed cornea is subject to desiccation and infection and can be avoided by frequent application of a broad-spectrum antimicrobial ointment every 3 or 4 hours until the animal is 10 to 12 days old. Cats with lysosomal storage diseases may develop corneal opacities related to the accumulation of polysaccharides within the endothelial cells and fibroblasts of the cornea. Fine granular deposits in the corneal stroma may Read more […]

Cystic Endometrial Hyperplasia / Pyometra

Development Pyometra is a relatively common disorder of older intact female dogs. True incidence is not known because most bitches in the United States are spayed when they are young. Pyometra is a two-step process with initial cystic endometrial hyperplasia (CEH) followed by infection. As the name implies, CEH is a cystic thickening of the endometrium, or uterine lining (). CEH can be created experimentally by exposing uterine tissue either to estrogen or to progesterone. Cystic endometrial hyperplasia develops to a greater extent and more quickly if the uterus is first exposed to estrogen and then is exposed to progesterone. This is the normal hormonal sequence of the estrous cycle in dogs. CEH develops over time after repeated estrous cycles in the dog. There are four grades of cystic endometrial hyperplasia described by Dow: worsening in severity from type I (mild changes) to type IV (severe changes with associated inflammation and tissue destruction). As might be expected because this is a progressive disorder, mean age at diagnosis of dogs with type I CEH is younger than is mean age of dogs diagnosed with type IV CEH. By the age of 9 years, two thirds of intact bitches had some degree of cystic endometrial Read more […]

Idiopathic dilated cardiomyopathy

Dilated cardiomyopathy (DCM), next to valvular endocardiosis, is the most commonly diagnosed cardiac disorder in dogs. In most cases the cause is not apparent; the most popular concept is that the aetiology for dilated cardiomyopathy in dogs is multifactorial. Cases of dilated cardiomyopathy in association with a deficiency of myocardial L-carnitine have been reported in one family of boxers suggesting that nutritional factors may be involved in the pathogenesis. L-Carnitine is necessary for the transport of long chain fatty acids into the mitochondria of cardiac muscle cells and a deficiency results in impaired mitochondrial energy production. More recently, it has been shown that some dogs with dilated cardiomyopathy have reduced plasma taurine levels. In humans, cardiomyopathy is associated with depression of the cellular Na+, K+-ATPase pump and a reduction (down regulation) of myocardial beta-adrenergic receptors. Whether a similar situation exists in dogs with dilated cardiomyopathy is not clear. A recent study reported no significant difference in the beta receptor density in four dogs with dilated cardiomyopathy compared to normal dogs. Immune-mediated disease with the production of antibodies against altered Read more […]