A Retrospective Study of Horner Syndrome in Australian Wild Birds, 2010-2016

Tick paralysis in Australian birds caused by Ixodes holocyclus

Tick paralysis is an uncommon cause of neuromuscular paralysis affecting 0.12% of wild birds presented to Currumbin Wildlife Sanctuary, Queensland, with a strong seasonal predilection towards spring and summer. Clinical signs and progression of paralysis showed similarities to companion animals and were consistent across 20 species. Tick location, number of engorged ticks and number of clinical signs did not affect the outcome; however, all mortalities occurred within 4 days of admission. Treatment with canine-derived tick antiserum resulted in clinical improvement within 24 h and a recovery rate of 73%. Average time to resolution of clinical signs was 4.3 days, with juvenile birds recovering more quickly than adults. The treatment and release of wild birds affected by tick paralysis are both achievable and rewarding, further research is required to establish treatment guidelines in birds.

Horner Syndrome With Ipsilateral Wing Paresis in a Wild, Juvenile Yellow-Tailed Black Cockatoo (Calyptorhynchus funereus)

A juvenile yellow-tailed black cockatoo (Calyptorhynchus funereus) was presented with paresis of the right wing, ptosis, and miosis of the right eye; feather erection of the right side of the head and neck; and a penetrating injury over the right pectoral muscle. Temporary reversal of ptosis, miosis, and feather erection after administration of phenylephrine drops confirmed a diagnosis of Horner syndrome. Computed tomographic imaging revealed a fractured rib, traumatic lung lesions, and subcutaneous emphysema. The right-sided Horner syndrome and wing paresis were attributed to a sympathetic nerve trauma of the eye and feathers and to the brachial plexus, respectively. This report describes the diagnosis and resolution of ptosis and miosis within 8 weeks and recovery of feather symmetry and wing function within 11 weeks of the cockatoo's initial presentation with a conservative-management treatment plan.