Conflicts in opinion on the implications of taming feral cats exist. The rescue workers typically felt that most cats could be tamed, whereas the veterinary surgeons felt this was generally inappropriate, except in the case of young kittens. A consistent definition of feral cats would enable better communication regarding the welfare and management of these animals, and would be useful for further research and education of the public. PROPOSED DEFINITION: A feral cat is proposed by this study to be a cat that is unapproachable in its free-roaming environment and is capable of surviving with or without direct human intervention, and may additionally show fearful or defensive behaviour on human contact.

A 20-year-old Warmblood mare was evaluated for acute-onset tachycardia and a one-week history of lethargy and ventral oedema. Haematology revealed leucocytosis with neutrophilia. Ultrasonographic examination revealed pericardial effusion and cardiac tamponade consistent with right-sided congestive heart failure. Abdominal ultrasonography demonstrated loss of definition of the right kidney and a structure adjacent to the kidney suggestive of a renal neoplasm. A tentative antemortem diagnosis of multicentric neoplasia, most likely lymphoma, was made. The horse was subjected to euthanasia due to a grave prognosis. Postmortem examination and histological evaluation were consistent with lymphoma, including infiltration of the cardiac muscle with neoplastic cells. Although lymphoma has been reported to affect the heart, congestive heart failure due to cardiac and pericardial neoplastic infiltration has not been previously reported as the presenting complaint. This case report describes the diagnostic approach to pericardial effusion and congestive heart failure in a mare with lymphoma.