Question

Strongylus vulgaris

A) organ(s) or tissue(s) where adult stage can be found: (options: large intestine, respiratory tract, kidney, or small intestine)

B) intermediate host: (options: infected definitive host, none, earthworm, or aquatic oligochaetes)

C) life stage that is infectious to definitive host: (options: L3, embryonated egg, L1 in muscle, or encysted larvae/L3)

Answer 1

(A)The answer is the large intestine, the L3 stage of the parasite enter the intestinal mucosa and develop into the L4 stage. During this stage, the parasite can enter the blood vessels and migrate throughout the body. They can feed in the large intestine and causes weight loss.

(B) The intermediate host of this parasite is none, because the development of into sexually mature stage happens in the same host as the host where its asexual stage is found.

(C) The infective stage of this parasite is L3, where it is ingetsed by the host and, enters the mucosal wall of the intestine to further develop.