Serratospiculosis in falcons from Kuwait: incidence, pathogenicity and treatment with melarsomine and ivermectin

The aims of this study were to determine the incidence of the filarial avian nematode Serratospiculum seurati in falcons from Kuwait, report clinical signs and find an effective therapy. Naturally occurring S. seurati infestation was diagnosed in 149 (8.7%) out of 1,706 captive falcons examined between May 2003 and April 2005, and 140 of these were treated with melarsomine at dosage of 0.25 mg/kg injected intramuscularly for two days, and ivermectin, injected once at the dose of 1 mg/kg, 10 days later. Infestation was reportedly symptomatic in 107 (71.8%) and non-symptomatic in 42 (28.2%) falcons. Signs reported more often were dyspnoea (58.8%), reduced speed and strength in flight (56%), weight loss (38.3%), anorexia/poor appetite (22.4%) and lethargy (16.8%). After administration of melarsomine, signs disappeared within 1-10 days in symptomatic birds and improvement of flight performances was noted in non-symptomatic birds. Dead adult parasites were ejected in 22 cases. Embryonated eggs were not detected in coproscopic checks made 10 and 40 days after the end of therapy, in association with lasting clinical remission. The main conclusion is that Serratospiculum seurati is overall pathogenic for birds of prey in the Middle East and that melarsomine + ivermectin can be an effective protocol of therapy eliminating both clinical signs and parasites.