Diagnosis of Mycoplasma columborale in a fledgling kererū (Hemiphaga novaeseelandiae)

Abstract

ABSTRACT Case history: In early summer, a wild fledgling kererū (Hemiphaga novaeseelandiae) was admitted to a wildlife hospital in Dunedin after falling from its nest and being found on the ground. Clinical findings: The bird was underweight, weighing only 391 g (expected weight > 450 g), and determined to be in poor body condition based on palpation of pectoral muscle mass. There was bilateral periorbital swelling and ocular discharge with caseous material blocking the choana. Samples of the ocular and choanal discharge were collected and submitted for molecular testing. General anaesthesia was required for further radiographic assessment, and the bird was stabilised for 48 hours with oral electrolytes and antimicrobial and analgesic therapy with doxycycline, meloxicam, and tramadol administered orally twice daily via crop tube and voriconazole administered once daily. Chloramphenicol was applied topically to the eyes twice daily. Subsequently, due to the severity of the gross and radiographic lesions, the likelihood of the need for an extended period of treatment, the age of the chick, its weakened and underweight condition and the risk of imprinting, the bird was euthanased while under general anaesthesia. Laboratory and pathological findings: PCR testing ruled out Chlamydia psittaci as a cause of morbidity and instead identified Mycoplasma columborale. On gross post-mortem examination, there was caseous material in the periorbital tissues, sinuses and choana. Samples of the choanal discharge grew a moderate mixed growth of Escherichia coli and Enterococcus faecalis. Diagnosis: Severe pyogranulomatous sinusitis associated with infection with M. columborale. Clinical relevance: This report describes the first isolation of M. columborale in any species in New Zealand and the first diagnosis of mycoplasmosis in a native kererū. The significance of this finding has not yet been determined.