Intensity of Toxocara canis shedding of foxes in the North-Eastern part of the Netherlands

Abstract

Objectives: To determine the prevalence and intensity of Toxocara canis infection in foxes in the Netherlands and to investigate associations between T. canis presence, and eggs per gram (EPG), EPG per female worm (EPG/FW) and age, gender and body-weight-length (BWL) index.

Methods: Between October 2016 and January 2017, 69 foxes were shot in the north-eastern part of the Netherlands. Before dissection on these foxes, data on age, gender, weight and length was collected. During dissection, faeces and T. canis worms were collected. The worms were counted and sexed using a stereomicroscope. The Centrifugal Sedimentation Flotation (CSF) method was used for faecal examination, and the McMaster technique to determine the EPG when T. canis eggs were present.

Results: The prevalence of T. canis was 63,8%, the mean EPG was 472, and the mean EPG/FW was 78. No significant relations were found between T. canis presence, EPG, EPG/FW, and age, gender or BWLindex. One T. canis worm was found inside the right atrium of a fox’s heart.

Clinical significance: The EPG/FW of T. canis in Dutch foxes has been determined for the first time and is a prelude to a more quantified collection of data regarding T. canis infections in animals. This study provides a first indication about the intensity of infection and the actual contribution of foxes to environmental contamination with T. canis eggs in the Netherlands.