Control of Hymenolepis nana infection as a measure to improve mouse colony welfare.

After cannibalism had appeared in the reproductive units of a white mouse colony, treatment against confirmed Hymenolepis nana, a tapeworm with zoonotic potential, was performed on 67 mice in the reproductive and nursery units. Faecal droppings were evaluated by flotation and sedimentation methods. The sedimentation method revealed a higher number of positive results before, during and after the treatment, but the flotation method yielded some additional positive cases. In the reproductive unit, H. nana eggs were confirmed in 50% of the tested mice by the flotation and in 70% by the sedimentation method. In the nursery units, H. nana eggs were detected in 10.5% of the tested mice by the flotation and in 24.6% by the sedimentation method. A colony of mice was treated against the tapeworm H. nana with praziquantel and emodepside in doses of 2.574 mg praziquantel/100 g body mass and of 0.642 mg emodepside/100 g body mass. The content of the original pipettes (Profender®) was applied as a spot-on on the back of the neck in the area between the shoulders. The application was repeated three times at 14-day intervals. Seven days after the third therapy no H. nana was found in any of the tested mice in the reproductive or the nursery units. After the treatment, cannibalism was no longer observed. This treatment represented one of the steps aimed at improving animal welfare and preventing potential zoonotic disease. The public health significance of this cestode should receive more attention, especially among people who take care of mice, have them as pets, or feed them to reptiles.