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Effect of fenbendazole on three behavioral tests in male C57BL/6N mice
Bharathi S Gadad1, João P L Daher, Eric K Hutchinson
1Neuroregeneration Program, Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Abstract:
Pinworms are highly contagious parasites of laboratory rodents that often are treated with fenbendazole. To our knowledge, the effect of fenbendazole at therapeutic dosages on behavioral tests in mice has not been evaluated. Here we studied 6-wk-old male C57BL/6N mice. We compared the behavior of control mice (fed regular diet) with 3 groups of mice treated with dietary fenbendazole. Treatment groups were 4 wk of fenbendazole, 2 wk of fenbendazole followed by 2 wk of regular diet, and 2 wk of regular diet followed by 2 wk of fenbendazole. At the end of dietary treatment all groups were tested by open field for central, peripheral and vertical activity; elevated plus maze for anxiety; and rotarod for motor ability and then evaluated by clinical pathology and selected histopathology. Treated and control groups showed no differences in open field or elevated plus maze testing, histopathology, or clinical pathology. However mice treated for 4 wk with fenbendazole or 2 wk of fenbendazole followed by 2 wk regular diet stayed on the rotarod for shorter periods than did controls, and mice treated with 2 wk of regular diet followed by 2 wk fenbendazole showed a trend toward shorter rotarod times. In light of this study, we suggest that open field and elevated plus maze testing is unlikely to be affected by 4 wk fenbendazole treatment in male C57BL/6 mice; however, behavioral tests of motor ability such as rotarod tests may be affected during and for at least 2 wk after fenbendazole treatment.
Insights
Fenbendazole, used to treat pinworms in rodents, did not affect anxiety or general activity in mice. However, motor skills tested by rotarod were impaired during and after treatment.
Area of Science:
- Veterinary Medicine
- Neuroscience
- Pharmacology
Background:
- Pinworm infections are common in laboratory rodents and frequently treated with fenbendazole.
- The impact of therapeutic fenbendazole dosages on rodent behavior, particularly in standardized tests, remains largely uncharacterized.
Purpose of the Study:
- To investigate the effects of dietary fenbendazole administration on behavioral outcomes in male C57BL/6N mice.
- To evaluate fenbendazole's influence on motor coordination, anxiety-like behavior, and general activity.
Main Methods:
- Male C57BL/6N mice were administered fenbendazole via diet for varying durations (4 weeks, or 2 weeks with a 2-week washout).
- Behavioral assessments included open field (activity), elevated plus maze (anxiety), and rotarod (motor ability).
- Clinical pathology and histopathology were performed post-treatment.
Main Results:
- No significant differences were observed between fenbendazole-treated and control groups in open field or elevated plus maze tests.
- Mice treated with fenbendazole for 4 weeks or with a 2-week treatment/2-week washout regimen showed reduced latency on the rotarod.
- A trend towards shorter rotarod performance times was noted in mice receiving 2 weeks of fenbendazole after a 2-week diet period.
Conclusions:
- Fenbendazole treatment at therapeutic doses does not appear to affect anxiety or general locomotor activity in male C57BL/6 mice.
- Motor function, as assessed by rotarod performance, may be impaired during and for at least two weeks following fenbendazole administration.
- Researchers should consider potential motor deficits when interpreting rotarod data from fenbendazole-treated rodents.
