PHYCOMYCOSIS OF THE HORSE CAUSED BY BASIDIOBOLUS HAPTOSPORUS

A case of subcutaneous phycomycosis of a horse from which Basidiobolus haptosporus was isolated is described. Although some clinical signs were similar to the disease caused by Hyphomyces destruens , the gross and microscopic pathology were different in several respects. Main characteristics of the histopathology were the narrow eosinophilic sleeve around wide, frequently septate hyphae scattered throughout the affected tissue and found commonly at the advancing border of the lesion. A retrospective study of 63 cases of phycomycosis diagnosed at this laboratory since 1970 indicated a further 11 cases with similar histological features. The significance of this finding for the epidemiology and pathogenesis of equine dermal granulomas is discussed.     

SNAKEBITE IN THE HORSE

Four cases of snakebite in horses are presented. Diagnosis was made on clinical signs in all, plus fang punctures in 2 cases. Tiger snake antivenene was used in the treatment of 2 patients and these recovered rapidly. Of the 2 in which antivenene was not used, 1 severely affected horse died. The clinical signs which were observed were those of progressive general paralysis and were entirely referable to the neurotoxic component of the venom.     

SPLENECTOMY IN THE HORSE

SUMMARY Splenectomy was successfully performed on 2 aged horses to facilitate experimental studies of Babesia equi infection. Resection of part of the 17th rib provided the most acceptable approach and avoided many complications encountered on removing part of the 16th rib.     

SINUS SURGERY IN THE HORSE

Infection in the maxillary sinus occurs frequently in the horse. It is possible to have primary maxillary sinusitis often caused by Streptococcus equi, however the most common cause of sinus infection is extension of infection from a diseased tooth or as an aftermath to tooth repulsion. The involved tooth can be a split tooth, an open infundibulum caused by a congenital defect, and in older horses, paradontal disease.     

ON NAVICULAR DISEASE IN THE HORSE

Radiolucent crescents found in the cortical bone of the flexor central eminence are normal variations of equine navicular bones and represent the radiographic presentation of a curvature in the central eminence that is best visualized when a dorsoproximal-palmarodistal beam angle of approximately 45° is used.