Trichuris vulpis

Trichuris vulpis
Kingdom	Animalia
Phylum	Nematoda
Class	Enopla
Sub-class	Dorylaimia
Order	Trichocephalida
Super-family	Trichinelloidea
Family	Trichuridae
Genus	Trichuris
Species	T. vulpis

Trichuris vulpis egg - Joel Mills, Wikimedia commons

Overview

Thrichuris vulpisis a typical whipworm in appearance and life cycle. The worms have a pre-patent period of 3 months before eggs are found in feaces, though they are not always present and several samples may be necessary to confirm infection. It inhabits the large intestine and ceacum of dogs and less often foxes and cats worldwide. Commonly seen in the caecum, but rarely in large enough quantities to cause clinical signs, most notably diarrhoea in dogs.

Identification

Adults are between 4.5 and 8cm long, slender and white coloured. The anterior end is long and filamentous becoming broader towards the posterior. The males tail is coiled and has a single spicule, used for reproduction, in a protrusible sheath. Eggs are distinctive lemon shaped with a thick shell and bioperculated having plugs at each pole. The eggs appear yellow/brown colour in the faeces.

Epidemiology

T. vulpis can be found in many places throughout the world. The longevity of the eggs is the major feature of the spread of these worms as they can survive in the environment for a number of years under suitable conditions. As light infections can be carried asymptomatically, host animals can spread the disease readily. Older dogs tend to have a higher burden than younger dogs due to accumulation over the life of the animal.