Journal of Parasitic Diseases

, Volume 43, Issue 4, pp 679–685 | Cite as

Larval distribution, migratory pattern and histological effects of Toxocara canis in Rattus norvegicus

  • Kennesa Klariz R. LlanesEmail author
  • Cyrelle M. Besana
  • Vachel Gay V. Paller
Original Article


The common dog roundworm Toxocara canis can infect other animals and humans which may act as their paratenic and accidental hosts, respectively. Larvae do not further develop to adult worms in these hosts. Instead, they undergo migration to various body organs, causing the neglected parasitic disease known as toxocariasis. Although rats are considered as potential paratenic hosts of the parasite, there are only few studies which utilized Rattus norvegicus (Sprague–Dawley strain) for experimental infections involving toxocariasis. This study aimed to determine whether T. canis could establish in Sprague–Dawley rats artificially infected with 500 T. canis embryonated eggs and if the animals can be used as animal models for toxocariasis. Following squash method and tissue digestion, larvae were recovered from the lungs, liver and brain of the infected rats. Furthermore, gross examination of organs revealed macroscopic lesions and hemorrhages in the lungs and brain. Microscopically, accumulation of inflammatory cells, thickening of alveoli lining and destruction of bronchial walls and hepatic necrosis were observed. This study showed that T. canis has established in Sprague–Dawley rats and could serve as a model for Toxocara infection studies.


Toxocara canis Larval migration Artificial infection Paratenic hosts Rats 



The authors would like to sincerely thank the University of the Philippines Enhanced Creative Work Research Grant (ECWRG) for the partial funding of the study.

Author contributions

Conceived and designed the experiments: VGVP, KKRL, CMB; Performed the experiments: KKRL, CMB; Data analysis: KKRL; Contributed reagents/materials/analysis tools: VGVP, CMB, KKRL; All authors participated in writing the final paper.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Indian Society for Parasitology 2019

Authors and Affiliations

  1. 1.Animal Biology Division, Institute of Biological Sciences, College of Arts and SciencesUniversity of the Philippines Los BañosCollegePhilippines
  2. 2.Department of Biological Sciences, College of Arts and SciencesUniversity of Southern MindanaoKabacanPhilippines

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