Infections of the gastro-intestinal tract

A large variety of nematodes occur in the gastro-intestinal tract of zebras. These include the ascarid Parascaris, the spirurids Draschia and Habronema, the strongylid genera Strongylus and Triodontophorus and a whole host of cyathostomins, such as Cylicodontophorus, Cylicostephanus, Cyathostomum, Cylicocyclus, Poteriostomum, and Oesophagodontus. The Habronematidae are represented by Habronema and Draschia, while Oxyuris equi (Oxyuridae) and Trichostrongylus thomasi (Trichostrongylidae) are usually present in small numbers. The Family Atractidae are tiny worms and occur in tens of thousands rather than tens or hundreds.

Krecek (1984) listed the helminths from 10 zebras shot in the KNP and a summary of the range of numbers of the helminth families that were collected is presented in Table 7.

Table 7: The numbers of worms recovered from zebras from the KNP

Nematode family	Range
Strongylidae
Strongylinae	1 - 137
Cyathostominae	1 - 159 491
Atractidae	2 - 24 206 530
Habronematidae	4 - 1 864
Oxyuridae	5 - 1 515
Trichostrongylidae	20 - 580

Anoplocephala and Anoplocephaloides are tapeworms that occur in the small intestine, and are not associated with lesions or clinical disease.

Gastrodiscus aethiopicus has been recorded from zebras but its pathogenicity, if any, is unknown.

In conclusion, as far as helminthoses in wildlife are concerned, it is probably best expressed by Robbie Bain’s (2003) comment: “For the time being, an African perspective of the helminths of wildlife is best summed up with the image of the zebra grazing the savanna – fat, happy and full of worms”.