EVALUATION OF CLINICAL DIAGNOSTICS FOR PROVENTRICULAR NEMATODIASIS DUE TO SYNHIMANTUS NASUTA IN LORIKEETS (TRICHOGLOSSUS SPP.).

Abstract

In this case series, clinical investigations were pursued during a Synhimantus nasuta infection in a lorikeet (Trichoglossus spp.) flock outbreak situation to better describe and document clinical presentations. In 11 lorikeets suspected to be infected with Synhimantus based on at least one abnormal finding on their physical examination (lethargy, feather-damaging behavior on the ventrum, weight loss, pale iris), the presence of five additional parameters was documented: anemia, relative eosinophilia, increased proventricular diameter-to-keel height ratio (PKR), proventricular barium filling defect, and positive fecal occult blood detection test. A total score (X of 9) was calculated by combining all these findings. Synhimantus nasuta infection was confirmed in four of these individuals by modified Wisconsin fecal examination. Suspected cases (n = 7 of 11) presented only with low scores (1-3 of 9), whereas birds with confirmed infections (n = 4 of 11) presented with both low (1-3 of 9, n = 2 of 4) and high (6-7 of 9, n = 2 of 4) total scores. High scores were associated with clinical anemia. Fecal occult blood was present in all confirmed cases and 4 of 7 suspected cases. An enlarged proventriculus was only observed in birds with active shedding (n = 3 of 4). Follow-up evaluations after 6 mon of treatment with ivermectin and selamectin suggested complete recovery with lowered or normalized total scores. In conclusion, during an S. nasuta outbreak, a rapid physical examination helps to identify suspect cases, including individuals requiring immediate medical attention. In the absence of ova shedding, infection cannot be excluded on the basis of scarce clinical findings, but the detection of occult fecal blood and an increased PKR should raise the index of suspicion.