infestation of tracer lambs by fasciola hepatica in tunisia: determining periods for strategic anthelmintic treatments. | ovine fasciolosis causes high morbidity and mortality rates, resulting in large economic losses to the sheep industry in northern tunisia. the authors surveyed ovine fasciolosis (fasciola hepatica infestation) in a barbarine sheep flock in the humid region of tunisia (sejnane, governorate of bizerte) over two consecutive years, 2004 to 2005. to assess the dynamics of fluke infestation, a total of 36 tracer lambs were introduced into the flock successively, in groups of three, every two months, a ... | 2011 | 22435202 |