Abstract: | Administration of 100 ppm fenbendazole to 661 pheasants (Phasianus colchicus colchicus) and 25 partridges (Perdix perdix) for 4 days reduced natural infection with Syngamus trachea and/or Capillaria obsignata and in some cases with Heterakis spp. by more than 90%. A 5-day administration of feed medicated with 30 or 60 ppm fenbendazole resulted in almost 100% efficacy against natural C. obsignata and Heterakis gallinae infection in 343 pullets. The treated pullets were kept under poor hygienic conditions, resulting in slight reinfection, which manifested itself in immature nematode stages at autopsy and in a slight excretion of nematode eggs in individual cases. Fenbendazole treatment effected the clinical recovery of the stocks within a few days and was very well tolerated. |