Vet' Medicine

Mammary Glands Diseases in Animals

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The mammary glands are specialized structures responsible for milk production and nourishment of offspring. Their proper function is essential for neonatal survival, maternal health, and productivity in livestock systems. Diseases of the mammary glands can lead to reduced milk yield, poor milk quality, systemic illness, and economic losses. Among these conditions, mastitis and structural defects of the udder and teats are particularly significant, alongside syndromes such as Mastitis–Metritis–Agalactia in sows.

Mastitis

Mastitis is the inflammation of the mammary gland, most commonly caused by bacterial infection. It is one of the most economically important diseases in dairy animals, especially cattle, but also occurs in sheep, goats, and other species.

Pathogens typically enter through the teat canal, leading to infection and inflammation of the glandular tissue. Mastitis may be classified as:

• Clinical mastitis: Characterized by visible signs such as swelling, heat, pain, and abnormal milk (e.g., clots, discoloration)
• Subclinical mastitis: No obvious external signs, but milk quality and yield are affected, often detected through laboratory tests

The inflammatory response results in increased somatic cell count and reduced milk production. Severe cases may lead to systemic illness, including fever and anorexia.

Management includes antimicrobial therapy, anti-inflammatory treatment, and supportive care. Preventive measures—such as proper milking hygiene, teat disinfection, and good housing conditions—are essential in controlling mastitis.

Defects of Teats and Udder

Structural abnormalities of the teats and udder can interfere with milk flow and predispose animals to infection.

Common defects include:

• Teat stenosis: Narrowing of the teat canal, making milking difficult
• Supernumerary teats: Extra teats that may or may not be functional
• Teat injuries: Caused by trauma, leading to pain, infection, or obstruction
• Udder edema: Swelling of the udder, often seen around parturition
• Pendulous udder: Excessively large or poorly supported udder, increasing the risk of injury and contamination

These defects can impair milk ejection, increase the risk of mastitis, and reduce productivity. Management may involve surgical correction, proper milking techniques, and supportive care.

Mastitis–Metritis–Agalactia (MMA) in Sows

Mastitis–Metritis–Agalactia (MMA) is a complex postpartum syndrome affecting sows, typically occurring within a few days after farrowing. It involves inflammation of the mammary glands (mastitis), infection of the uterus (metritis), and reduced or absent milk production (agalactia).

The condition is often associated with bacterial infection, poor hygiene, stress, and inadequate management during the periparturient period. Clinical signs include:

• Reduced milk production or failure to lactate
• Swollen, painful mammary glands
• Fever and lethargy
• Vaginal discharge (in cases of metritis)
• Poor growth or starvation in piglets due to lack of milk

MMA has significant implications for piglet survival and sow health. Treatment involves antimicrobial therapy, anti-inflammatory drugs, fluid therapy, and measures to stimulate milk letdown. Good management practices—such as proper sanitation, nutrition, and minimizing stress—are critical for prevention.

Conclusion

Diseases of the mammary glands, including mastitis, structural defects, and syndromes such as MMA in sows, are of major importance in veterinary medicine. These conditions not only affect animal health and welfare but also have significant economic consequences in livestock production. A thorough understanding of their causes, clinical signs, and management strategies is essential for effective prevention and treatment. By applying sound husbandry practices and timely veterinary care, the impact of these diseases can be significantly reduced.