Lumps – Rabbit

Introduction

Cutaneous and subcutaneous masses in rabbits are due to:

• Abscesses
• Coenurosis
• Skin tumours appear to be fairly uncommon in rabbits but squamous cell carcinomata, basal cell tumours, trichoepitheliomata, sebaceous cell carcinomata and chancres due to Treponema sp have been recorded (Weisbroth 1994).

Steatitis

Clinical signs

• excess fat in the skin fold areas
• commonly become inflamed
• nodular swellings in that region.
• enlarge to such a size that normal behavioural processes, such as coprophagy and grooming.

Treatment

• Surgical removal of discrete masses, or dewlap reduction where no obvious mass is present
• Excised tissue should be submitted for histopathology to rule out neoplasia

Histopathology

• normal adipose tissue
• patchy inflammation (cells mostly necrotic) extending to severe, chronic inflammatory changes
• marked fibrosis.

Plasmacytoma

Although rare, it has been reported in one animal. The cytology report from the aspirate was:

Two coverslips are examined that are highly cellular with moderate numbers of RBCs scattered throughout the sample. High numbers of plasmacytoid cells are observed that have light to moderate basophilic cytoplasm with low to high nucleus:cytoplasm ratio and show marked pleomorphism. The nuclei are round and often eccentric with variably clumped chromatin and occasional perinuclear clear zones. Marked anisocytosis and anisokaryosis are observed. Low numbers of binucleated and multinucleated cells are observed as well as mitoticfigures. Few macrophages are seen.

Unfortunately treatment was refused by the owner and the case was lost to follow-up.(White pres comm. 2005)

References

Weisbroth 1994