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Baylisascaris Potosis Larvae in Mice of Different Strains and Infectivity of Tissue Larvae
K Taira1, M Takechi1, H K Ooi1
1Laboratory of Parasitology, School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Sagamihara, Kanagawa 252-5201, Japan.
Abstract:
Migration of Baylisascaris potosis larvae in different mouse strains were compared, and infectivity of the persisting larvae in mice tissues were investigated. Five strains of mice, BALB/c, C57BL/6, AKR, B10.BR, and ICR were inoculated with 1,000 B. potosis eggs/mouse, and necropsied at week 13 post inoculation (PI). The other uninfected ICR mice (secondary host) were inoculated with 43 larvae/ mouse recovered from mice at week 13 PI with eggs, and necropsied at day 21 PI. Larvae in organs or tissues were counted at necropsy. One AKR mouse showed torticollis and circling at day 56 PI. At necropsy at week 13 PI, larvae were recovered from all mice. A mean total larvae recovered were 124.1 (n=40). Majority of larvae were found in the carcass (mean 113.9) and some in the viscera (mean 9.9). Zero to 1 larva were found in the brain or eyes of some mice. There were no differences among the mouse strains in the number of larvae, except in the viscera; more larvae were seen in BALB/c or ICR than in B10.BR mice. No larvae were found in the secondary host mice. Present study demonstrated that B. potosis larvae migrate well in the carcass of any strains of mice, however, the tissue larvae did not infect the secondary host. Results of our present study suggest that B. potosis larvae is less aggressive for the nervous tissue migration than that of B. procyonis larvae which is commonly known to migrate in central nervous system of mammals and birds.
Insights
Baylisascaris potosis larvae migrate effectively within mouse carcasses but do not infect secondary hosts. These larvae show less aggressive nervous system migration compared to Baylisascaris procyonis.
Area of Science:
- Veterinary Parasitology
- Helminthology
- Comparative Pathology
Background:
- Baylisascaris species are known zoonotic parasites.
- Understanding larval migration patterns is crucial for disease control.
- Baylisascaris potosis infectivity in different hosts requires further investigation.
Purpose of the Study:
- To compare Baylisascaris potosis larval migration in five mouse strains.
- To assess the infectivity of persisting B. potosis larvae in secondary hosts.
- To evaluate the neuro-migratory potential of B. potosis larvae.
Main Methods:
- Five mouse strains (BALB/c, C57BL/6, AKR, B10.BR, ICR) were inoculated with B. potosis eggs.
- Mice were necropsied 13 weeks post-inoculation to count larvae in tissues.
- Larvae from infected mice were used to inoculate secondary ICR mice to assess infectivity.
Main Results:
- Larvae were recovered from all inoculated mice, predominantly in the carcass.
- No significant differences in larval burden were observed among mouse strains, except for viscera.
- No larvae were found in secondary host mice, indicating lack of infectivity.
Conclusions:
- Baylisascaris potosis larvae exhibit efficient migration within the carcass of various mouse strains.
- Persisting larvae in mouse tissues do not infect secondary hosts.
- B. potosis larvae appear less aggressive in migrating to nervous tissue compared to B. procyonis.
