Botryomycosis Staphylococcosis

Definition It is a chronic granulomatous infectious disease of equine, caused by Staph. sp., characterized by development of granuloma commonly located on the limbs near the point of elbow or scrotum (spermatic cord fistulae).

Etiology Staph. sp is commonly isolated from the lesions. There are reports on isolation of Actinomyces viscous.

Epidemiology Distribution: The disease present where equine is raised. Animal susceptibility: Horses, donkeys and mules. Mode of transmission: The disease is present following trauma or contamination of cutaneous wounds as castration wounds.

Clinical signs Morbidity and mortality rates are low. There are cutaneous lesions appear in form of papules, nodules (non pruritic and non healing), crusts and ulcers with formation of draining tracts. The lesion may be large solitary and resembles a tumor, the size of lesion may up to 10-20 cm in diameter, rupture of nodules discharge pus which is sticky mucoid and yellow and has whitish yellow seed or granules which is packed masses of Staph. sp. This lesion may be present on shoulder, neck, withers, ventral abdomen, udder, spermatic cord and limbs. The lesion on spermatic cord causes scirrhous cord resulting in formation of chronic discharging sinus at scrotum with fibrosis and abscessation of spermatic cord and testes. Metastasis of purulent lesions to internal organs as lung, liver, spleen and kidney may be occurs.

Diagnosis Field diagnosis: It depends on history, epidemiology of the disease and clinical pictures. Laboratory diagnosis: Samples: Pus, skin biopsy, blood and serum. Laboratory examinations: Direct microscopic examination of stained pus smear to detect staph sp. Culture of pus samples. Hematological and serological examinations.

Treatment Complete surgical excision of the lesion or local dressing of the lesions with prolonged course of systemic antibiotic.

Control Early diagnosis, isolation and treatment of infected animals, Prophylactic treatment of all cutaneous wound and abrasions and Adequate hygiene to prevent spread of infection.