[Inappropriate lactation syndrome in a Holstein heifer]

Area of Science:

• Veterinary Medicine
• Reproductive Endocrinology
• Bovine Reproduction

Background:

• Normal lactation and udder development in cattle are hormonally regulated.
• Unusual lactation in unbred heifers is uncommon and warrants investigation into potential hormonal imbalances.
• Ovarian abnormalities, including follicular cysts and tumors, can exhibit hormonal activity.

Observation:

• A 15-month-old unbred Holstein-Friesian heifer presented with significant udder swelling and lactation.
• Rectal palpation and ultrasonography revealed an enlarged right ovary with multiple cysts, initially diagnosed as follicular cystic ovary disease.
• Despite unsuccessful treatment for cystic ovaries, the heifer was later found to have a granulosa cell tumor on the right ovary upon slaughter.

Findings:

• Granulosa cell tumors and cystic ovarian changes can produce hormones that stimulate lactation.
• The heifer's unusual lactation was likely caused by hormonal activity from either the cystic ovarian changes or the granulosa cell tumor.
• Pathological examination confirmed a granulosa cell tumor, a potential source of aberrant hormone production.

Implications:

• This case highlights the importance of thorough reproductive tract examination in heifers with unexplained lactation.
• Ovarian pathology, particularly granulosa cell tumors, should be considered in the differential diagnosis of unusual lactation in young, unbred cattle.
• Early diagnosis and management of ovarian abnormalities can prevent prolonged or unnecessary treatments and inform prognosis.