Epidemiology of paramphistomosis in cattle
| Autor: | P.F. Rolfe, P. Nichols, J.C. Boray, G.H. Collins |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Wet season
Veterinary medicine Snails Cattle Diseases Snail Trematode Infections Disease Vectors Pasture biology.animal parasitic diseases Dry season Gastropoda Grazing Animals Paramphistomatidae Weather geography geography.geographical_feature_category biology Ecology Intermediate host Gyraulus biology.organism_classification Infectious Diseases Parasitology Cattle Seasons New South Wales |
| Zdroj: | International journal for parasitology. 21(7) |
| ISSN: | 0020-7519 |
| Popis: | The epidemiology of paramphistomosis in cattle was studied using tracer calves in a subtropical location in eastern Australia. Two species of paramphistomes were present; Calicophoron calicophorum and Paramphistomum ichikawai. The former species was the most abundant. Gyraulus scottianus and Helicorbis australiensis acted as intermediate hosts, respectively. Paramphistome burdens varied seasonally and were dependent upon the number of infected host snails. Peak fluke burdens and clinical paramphistomosis occurred in late summer in year 1 and early winter in year 2. The peak fluke burdens coincided with prolonged inundation of the grazing areas resulting in rapid multiplication and infection of host snails, and the period after the inundated areas dried out. The prevalence of infection in snails was high in both years, peaking at 98% in year 1 and 58% in year 2. The main host snail, G. scottianus, aestivated and retained infection for at least 24 weeks in soil, and in vegetable debris on the surface of the soil, resulting in rapid reappearance of host snails and infective metacercariae after the onset of seasonal rain. Metacercariae survived on herbage for up to 12 weeks, depending on the environmental conditions. Paramphistome burdens in calves could be predicted from the prevalence of infection in the host snail, the water levels and an index of surface water on the grazing site. Control of paramphistomosis during and after flooding may be achieved by removal of susceptible cattle from pasture or regular treatment during these periods. Strategic treatment during the dry season may reduce contamination of snail habitats and infectivity of the pasture in the following wet season. |
| Databáze: | OpenAIRE |
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