Cataracts in the Bichon Frise

Purpose To determine the clinical characteristics of possible inherited cataract in the Bichon Frise breed. These characteristics include the relative frequency, gender effects, site of first cataract formation, age of onset, relationship of age to cataract maturity, and other concurrent pre‐ and postoperative ophthalmic diseases. Methods Four different populations of Bichon Frise were examined. They included: (1) referred patients of the University of Florida (VMTH; 1990–2000); (2) patients from other universities and large institutions (VMDB; 1970–2000); (3) patients from the Canine Eye Registry Foundation (CERF; 1970–2000); and (4) special patients recruited from eye clinics and ACVO specialty practices (1995–2001). Blood samples were obtained from many patients for future DNA analyzes. Statistical comparisons between groups were by general linear and anova analyzes, and P < 0.05 was considered significant. Results The four populations of cataractous and total Bichon Frise dogs included: (1) UF‐VMTH: 57 cataractous dogs; (2) VMDB: 406 dogs (28%) with cataracts; total dogs ? 1407; (3) CERF: 505 cataractous dogs (6%); total dogs ? 8222; and (4) ACVO: 223 cataractous dogs (57%); total dogs ? 391. In each population group, gender did not affect cataract distribution. Dogs between 2 and 8 years of age were most frequently affected, and initial cataract involvement affected equally the anterior and posterior cortices. Immature cataracts occurred more often in younger dogs, and hypermature cataracts were more frequently diagnosed in older dogs. Dogs with early cataracts were encountered more frequently in the CERF population. Pre‐ and postoperative retinal detachments (RD) were not infrequently diagnosed in the UF‐VMTH and VMDB groups. RD in the UF‐VMTH and VMDB groups occurred in 33% and 13% of the patients, respectively. Conclusions Cataracts were first encountered in CERF and VMDB data between 1975 and 1979 and have increased since this time. As expected, both similarities and differences between the four different populations of Bichon Frise were encountered. Both sexes of dogs are equally affected. The anterior and posterior cortical areas of the lens were first involved and dogs 2–8 years of age are most frequently affected. Cataracts affected younger dogs in the CERF group and older cataractous dogs in the other populations. Cataract formation appears to be inherited in the Bichon Frise dog. The frequency of pre‐ and postoperative retinal detachments present higher risks for cataract surgery in this breed.     

Principles and applications of radiation therapy

Radiation therapy is emerging as a beneficial and increasingly accessible treatment option for companion animals with cancer. Various types of radiation are available with different properties that may make one more suitable than another for treating a specific tumor type. Radiation therapy can be used as the sole treatment or as part of a multimodality treatment course to result in local or locoregional tumor control, or as palliative therapy for pain control. When radiation is a potential treatment option, it should be considered early in the decision-making process to ensure that the appropriate diagnostics and other treatment modalities are considered to provide the best potential outcome. This article is intended to provide an overview of the types of radiation therapy that are available, the indications, and the potential acute and late radiation side effects.     

Polycythemia vera in a dog presenting with uveitis

A 2-year-old, castrated male, mixed-breed dog presented with a 1-month history of red eyes and intermittent vomiting and a 2-week history of polyuria and polydipsia. Bilateral anterior uveitis and active chorioretinitis in the left eye were found on ophthalmic examination. Complete blood counts demonstrated evidence of an increased red blood cell mass. Thoracic and abdominal radiographs, abdominal ultrasonography, and Doppler echocardiography were unremarkable. Serum erythropoietin level was low-normal, consistent with a diagnosis of polycythemia vera. Resolution of all systemic and ocular signs occurred, and remission was achieved following phlebotomy and treatment with oral hydroxyurea.     

Effects of delayed or prolonged fixation on immunohistochemical detection of bovine viral diarrhea virus type I in skin of two persistently infected calves.

The effects of delayed or prolonged fixation on immunohistochemical detection of bovine viral diarrhea virus (BVDV) antigen were evaluated in skin. Ear-notch specimens from 2 calves persistently infected with BVDV type 1 were handled in 1 of 3 ways: 1) fixed in formalin promptly and processed for immunohistochemistry (IHC) after 3-176 days; 2) held at 3-4degreesC in plastic bags up to 10 days, then fixed in formalin for 2-5 days before processing; or 3) exposed to room air and temperature for 1-5 days before formalin fixation. Immunohistochemical staining intensity was evaluated without the knowledge of specimen handling. Staining of specimens that had been promptly fixed in formalin was moderate to strong at all fixation periods through 36 days, weak or no staining was evident in specimens fixed for 176 days. Refrigerated specimens typically had moderate to strong immunohistochemical staining. Even after 10 days of refrigeration before fixation, all immunohistochemical reactions were positive. However, no immunohistochemical staining was detected in any specimen that was exposed to room air. Results indicate that prompt formalin fixation is optimal for BVDV IHC. Samples can be held in formalin at least 36 days, without loss of reactivity. A 1-day delay in fixation caused no loss of reactivity, provided the specimen was refrigerated and protected from desiccation.