Mammary Hyperplasia in a Main Coon Queen

Mammary fibroepithelial hyperplasia or fibroadenomatous hyperplasia (FAH) in cats is a benign generalized enlargement of one or more mammary glands reported in young queens during early pregnancy or pseudopregnancy, or in cats that have received an exogenous source of progesterone. A two-year old Main Coon queen that had been imported from Russia was presented to the Atlantic Veterinary College (AVC) due to a severe mammary gland enlargement. The queen had been exposed to a tomcat, and breeding. A typical after-mating reaction was reported to have occurred on several occasions. Mating occurred a month prior to presentation. On presentation, the queen was active, bright, alert and responsive, and physiological parameters were within normal range. The owner reported that the queen had a normal appetite and was still very playful. The chief complaint was the presence of severe mammary gland enlargement. Both right and left mammary glands, which included the most cranial thoracic and the most caudal abdominal/inguinal were swollen. However, both caudal mammary glands were the most affected and showed excessive enlargement with areas of purplish coloration, and areas suggestive of mild self-inflicted trauma ...