Transmission of canine transmissible venereal tumour between two dogs in the UK.

Canine transmissible venereal tumour (CTVT) is a contagious cancer spread by transfer of living cancer cells. Occasional cases are observed in the UK in dogs imported from endemic regions. Here, we report a case of imported canine transmissible venereal tumour that was transmitted to a second dog within the UK. Transmission of genital canine transmissible venereal tumour occurred despite neutered status of the second dog. The aggressive course of disease in both cases, which included metastasis, resistance to therapeutic interventions and ultimate euthanasia of both dogs, is described. The diagnosis of canine transmissible venereal tumour was made using a combination of cytology, histology, immunohistochemistry and PCR to detect the LINE-MYC rearrangement. Practitioners unfamiliar with canine transmissible venereal tumour are reminded of this disease of concern, particularly when imported dogs are placed in multi-dog households, irrespective of neuter status.

Comparative anatomy and angiography of the cardiac coronary venous system in four species: human, ovine, porcine, and canine.

INTRODUCTION: The coronary arterial system has been the subject of greater investigation than its venous system due to the importance of human coronary artery disease. With the advent of new percutaneous treatments, the anatomy of the coronary venous system has increasing relevancy. We compared the organization of the coronary venous circulation in three species commonly used in research and compared these to normal humans using both macroscopic anatomic and angiographic studies. ANIMALS: The anatomy of five explanted hearts from healthy dogs, pigs, and sheep were studied macroscopically, and 10 explanted hearts per animal species and 10 clinically normal human were examined by angiography. METHODS: Animal hearts were injected with latex and dissected macroscopically. The coronary venous system of humans was evaluated from clinical angiographic studies. In the animal hearts, a retrograde angiographic study was performed via a Foley catheter in the coronary sinus. RESULTS: The general organization of the coronary venous circulation was similar among humans, dogs, sheep, and pigs. Despite overall similarities to humans, animal hearts demonstrated the absence of the oblique vein of the left atrium and differences in position and organization of venous valves; venous diameters; number of tributary veins; and presence of an anastomosis between the left and right (human anterior and posterior) venous tree. The left azygos of the pig and sheep joined the coronary sinus. CONCLUSIONS: Anatomical differences must be considered when planning biomedical and veterinary studies incorporating cardiac veins. This study provides baseline data regarding structure and organization of the cardiac venous system.

Clinical relevance of radiographic linear branching mineral opacities in the canine liver.

OBJECTIVES: To assess the prevalence, clinical significance and breed distribution of linear branching mineralisation superimposed on the hepatic radiographic silhouette in dogs. MATERIALS AND METHODS: Retrospective review of radiographs or ultrasound images of dogs showing branching mineralisation in the liver. RESULTS: Over the 30-year review period, 17 cases were identified and the mineralisation had a predominantly ventral distribution. Seven of the 17 were cavalier King Charles spaniels, and four of the total 17 dogs were diagnosed with hepatobiliary system disease. Five dogs had repeat radiographs, of which four showed no change in the pattern and one developed the pattern 6 years after being diagnosed with cholangiohepatitis. Serum calcium concentrations were normal in all patients. Liver enzymes were markedly elevated only in the dog diagnosed with cholangiohepatitis. Histology performed on three patients showed no convincing evidence of primary liver disease. CLINICAL SIGNIFICANCE: Branching mineralisation in the liver parenchyma is a rare finding in dogs with little or no clinical significance and cavalier King Charles spaniels may be predisposed. Biopsy of the liver of affected dogs with no clinical or clinicopathological evidence of liver disease is unlikely to be helpful in these cases.