RESUMO
Dogs are reservoir hosts for Leishmania infantum, a protozoan parasite transmitted by phlebotomine sand flies. The anti-feeding and fast-killing efficacy of Scalibor® deltamethrin collars against experimental Phlebotomus perniciosus challenges on dogs was determined over 1 year. Two groups of 8 dogs each were fitted with placebo (control) or deltamethrin collars (treated) on Day 0 and exposed to sand flies approximately every 28 days up to Day 364. After each exposure, anti-feeding and fast-killing efficacy rates were determined by comparing blood-fed or live insects, respectively, in the treated vs. the control group. Blood-fed and live sand flies were significantly less in treated dogs as compared to control dogs at each assessment. The anti-feeding efficacy rate exceeded 90% except on Day 337 (89%) but increased again (96%) on Day 364. Fast killing efficacy was <74% over the study when considering all flies. However, this value increased cumulatively to 98% when only blood-fed flies were compared between groups. Scalibor® collars are highly effective at preventing P. perniciosus blood-feeding and in fast-killing flies taking a blood meal for up to 1 year after application. These strong and long-lasting effects are an important strategic component for L. infantum transmission control.
Assuntos
Doenças do Cão , Leishmania infantum , Phlebotomus , Psychodidae , Piretrinas , Animais , Doenças do Cão/parasitologia , Doenças do Cão/prevenção & controle , Cães , Nitrilas/farmacologia , Phlebotomus/parasitologia , Piretrinas/farmacologiaRESUMO
Dogs are the reservoir host of zoonotic visceral leishmaniasis (VL) caused by Leishmania infantum (Kinetoplastida: Trypanosomatidae). Both subclinically-infected and sick animals can be infectious to competent phlebotomine vectors. The degree and duration of insecticidal efficacy of an oral dose of fluralaner (Bravecto®; Merck Animal Health) was determined in dogs exposed to bites of Phlebotomus perniciosus (Diptera: Psychodidae), a main Mediterranean vector of VL. Twelve dogs allocated to two groups of six animals each were included in a parallel-group designed, negative-controlled, randomized, blinded, single-centre efficacy study. Group 2 was treated with fluralaner on day 0, and sand-fly exposure of both groups was performed on days 1, 28 and 84. Viability of blood-fed females was assessed up to 96 h after exposure and efficacy was measured as the survival rate of specimens fed on Group 2 versus those fed on Group 1. A mortality of 100% was recorded at 24 h in females fed on Group 2 at both days 1 and 28. Significant insecticidal efficacy was still observed on day 84, with > 50% mortality recorded by 48 h post blood meal in Group 2. Fluralaner treatment of dogs represents a promising and affordable method for reducing the pool of infected vectors in endemic settings of zoonotic VL.
Assuntos
Doenças do Cão/prevenção & controle , Controle de Insetos , Insetos Vetores , Inseticidas , Isoxazóis , Leishmaniose Visceral/veterinária , Phlebotomus , Administração Oral , Animais , Doenças do Cão/parasitologia , Cães , Feminino , Leishmania infantum/fisiologia , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/prevenção & controle , Masculino , Fatores de TempoRESUMO
The anti-hypertensive action of 2,6-dichlorobenzylideneaminoguanidine acetate (BR 750) is described. Inter-patient comparison pointed out its excellent tolerance, together with an anti-hypertensive activity at least equal to that of alpha-methyldopa.