Question

Villous atrophy is associated with
(A) Eimeria ovinoidalis
(B) Trichostrongylus colubriformis
(C) Nematodirus battus
(D) Strongyloides papillosus
Choose the correct answer from the options given below:

• A. (A), (B) and (D) only.
• B. (A), (B) and (C) only.
• C. (A), (B), (C) and (D).
• D. (B), (C) and (D) only.

Hint:

Any major parasite that invades or burrows into the small intestinal mucosa (such as coccidia and small intestinal roundworms) will inevitably cause some degree of villous atrophy as a pathological consequence.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Villous atrophy is a pathological change in the small intestine characterized by the shortening and blunting of intestinal villi.
This reduces the surface area available for nutrient absorption, leading to malabsorption, diarrhea, and weight loss. It is commonly caused by pathogens that damage the intestinal mucosa.
Detailed Explanation:
Let us examine each pathogen's effect on the small intestinal mucosa of sheep:
- (A) Eimeria ovinoidalis: This coccidian protozoan invades and destroys epithelial cells of the posterior small intestine and cecum, causing severe mucosal destruction and villous atrophy.
- (B) Trichostrongylus colubriformis: This nematode burrow in the mucosa of the small intestine, leading to epithelial damage, local inflammation, and severe villous atrophy (blunting of villi).
- (C) Nematodirus battus: The larval and adult stages of this roundworm damage the intestinal wall, leading to acute enteritis and severe villous atrophy.
- (D) Strongyloides papillosus: This threadworm burrows into the small intestinal mucosa, provoking inflammatory responses and mucosal damage that results in villous atrophy.
Since all of these small intestinal parasites of sheep destroy the mucosal architecture, they are all associated with villous atrophy.

Step 2: Final Answer:
The correct combination is (A), (B), (C) and (D), which corresponds to Option (C).