Farmers are familiar with the common presentation of abscesses as the cause of rapidly growing masses on their cattle, but not all are as they seem. It is important for abscesses to be diagnosed and treated properly. This may include a needle aspirate to confirm pus is present, local anaesthetic to provide pain relief, thorough cleaning of the skin before incision, stand back for a fountain of pus and a good flush, finishing up with the old faithful- blue spray. Antibiotics are not usually required.

This case involved a call for a lump with quite a different outcome. This heifer had a small lump (golf ball sized) as an R1, that was presumed to be a small abscess and left to heal. The lump had stayed the same size for a while, and then in the last 3 weeks or so (as an R2 heifer) had rapidly grown.

The Friesian heifer had a mass on her shoulder, approximately the size of a soccer ball on presentation. As she came through the yards the skin split to reveal bleeding, shiny black tissue. The appearance indicated that the mass was in fact a melanocytoma- a tumour of pigment producing cells. These tumours can grow to impressive sizes and are unable to be transported to the works if the skin is split, which they are prone to doing.

The heifer was prepared for surgery- clipped, cleaned and local anaesthetic ring block applied. The tumour was cut off, sewn up, then pain relief and antibiotics were given to the heifer. At that point she looked brand new but be warned, this surgery can create a blood bath! Sutures were removed after 14 days, she recovered well and was still in calf.

Melanocytomas are an uncommon cancer of cattle (about 5% of all cancers in bovines) and occur usually in young animals. Dark coloured breeds e.g. Angus, Friesian etc are especially prone. Most melanocytomas in cattle are benign, and surgical excision is curative. Approximately 20% of cases may feature spread to lungs or lymph nodes. These tumours are prone to bursting open which then means the animal is unsuitable for transportation to the works. They are often very vascular (can contain abnormal blood vessels) which in rare cases can result in huge blood loss. Surgery is the only curative option, with wide surgical margins the prognosis is good, recurrence is possible but uncommon.