Mammary Tumors in Small Mammals

Key Points

  • Mammary gland tumors are relatively common in rats and mice. Most rat mammary tumors are fibroadenomas. Mice more commonly have mammary adenocarcinomas.
  • Mammary tissue can occur anywhere along the shoulder, neck, ventrum, flank or tail base in rats and mice.
  • Mammary gland tumors are typically seen in middle-aged to older animals.
  • Mammary tumors are more common in male guinea pigs than in females, which is unique among mammals.
  • Neoplasia is relatively common in African pygmy hedgehogs, and mammary gland adenocarcinoma is one of the most common tumors reported in this species.
  • Always screen affected hedgehogs for concurrent disease since retrospective work has documented multiple tumors in approximately 10% of affected animals.

An important differential for lumps and bumps: Mammary gland tumors are relatively common in rats and mice, and are also seen in African pygmy hedgehogs and guinea pigs. Get the facts about mammary tumors in small mammals. Review diagnostics, management, prognosis and prevention of this important condition . . .

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