Review on the Biology of Fasciola Parasites and the Epidemiology on Small Ruminants

Abstract

Small ruminant fasciolosis is a serious problem in animal production in different areas of the world especially in Ethiopia. It is a wide spread trematodal disease affecting small ruminants (sheep and goats) and also other species of animals. Fasciola hepatica and Faciola gigantica are the parasitic species belonging to Genus Fasciola under the phylum platyhelminths. Fasciola hepatica was shown to be the most important fluke species in Ethiopian livestock and it requires snail of the genus Lymnae for the completion of its life cycle and its biological features; mainly its external body structures such as the teguments and spines besides the enzymes it secrets for exsheathment are responsible for its pathogenicity. Fasciola gigantica which is tropical species can exist up to 2600m of elevation although an effective transmission cycle in a single year can only be maintained at elevation below 1700m. Availability of suitable ecology for snail; temperature, moisture and pH are factors influencing the agent and its epidemiology. The course of the disease runs from chronic long lasting to acute rapidly fatal. These give rise to application of different diagnostic methods including fecal egg examination, post-mortem examination, immunological assessment and serological liver enzyme analysis. Therefore, people have to be aware of the significance (both economic and public health significance) and have to do all their best so as to minimize the occurrence or control the disease by taking measures like forecasting the occurrence, reduction of snail population, prophylactic use of anthelmintic and immunologic approach.

Keywords: Fasciola, Biological characteristics, Small Ruminants, Epidemiology