Evaluation of the Mammary Gland

The mammary gland plays a key role in allowing the fetus to survive outside the uterus. It is responsible for providing the neonate with colostral antibodies critical to survival and supplies nutrition to the foal during the first few months of life. Abnormalities of the equine mammary gland include agalactia, premature lactation, inappropriate lactation, and mastitis. Less common issues include abscessation, neoplasia, and trauma. This chapter discusses the processes involved in the evaluation of the mammary gland. An ultrasound examination may be performed following manual assessment of the mammary gland to evaluate a region for a potential mammary tumor or abscess. Biopsy of the mammary gland may be indicated for histologic verification of neoplasia. However, tumors of the equine mammary gland are rare and consequently biopsies of the udder are rarely performed.