Strongyloidea

There are several important parasites of domestic mammals and birds in this superfamily of bursate nematodes.

·         Most are characterized by a large buccal capsule which often contains teeth or cutting plates and in some there are prominent leaf crowns surrounding the mouth opening.

·         The adults occur on mucosal surfaces of the gastrointestinal and respiratory tracts and feed­ing is generally by the ingestion of plugs of mucosa. With the exception of three genera, Syngamus and Mammomonogamus, which are parasitic in the tra­chea and major bronchi, and Stephanums found in the perirenal area, all other genera of veterinary impor­tance in this superfamily are found in the intestine and can be conveniently divided into two groups, the strongyles and hookworms.

·         The strongyles are parasitic in the large intestine and the important genera are Strongylus, Triodontophorus, Trichonema (cyathostomes), Chabertia and Oesophagostomum.

·         Hookworms are parasites of the small intestine and the three genera of veterinary importance are Ancylostoma, Uncinaria and Bunostomum.

strongyles:

·         Members of this genus live in the large intestine of horses and donkeys and, with Triodontophorus, are commonly known as the large strongyles.

Species	Hosts	Location	Distribution
Strongylus vulgaris S. edentatus S. equinus	Horses and donkeys	Caecum and colon	Worldwide

Identification:

Gross:

·         Robust dark red worms which are easily seen against the intestinal mucosa.

·         The well developed buccal cap­sule of the adult parasite is prominent.

Microscopic:

·         Species differentiation is based on size and the pres­ence and shape of the teeth in the base of the buccal capsule.

 

Species	Length	Identification
Strongylus vulgaris	1.5-2.5cm	Two ear-shaped rounded teeth
S. edentates	2.5-4.5 cm	No teeth
S. equines	2.5-5.0cm	Three conical teeth. One is situated dorsally and is larger than the others and bifid