Large Animal Parasites

Question 1

What is the most important nematode parasite of cattle in the sate of new york?

Answer 1

Ostertagia ostertagi “Brown stomach worm” (abomasal parasite)

Question 2

What are the major clinical signs for Type 1 and Type II infection with Ostertagia ostertagi?

Answer 2

Watery, profuse diarrhea most important! Persistent diarrhea in Type 1 (bright green) and intermittent diarrhea in Type 2. Also anorexia, weight loss.

Question 3

Which production group (of cattle) should be treated with anthelmintics?

Answer 3

Heifers!

Question 4

Name an important zoonotic protozoa of the cow large intestine?

Answer 4

Cryptosporidium parvum

Question 5

If you see anemia in a sheep - what are you going to assume is causing it (until proven otherwise?)

Answer 5

Haemonchus contortus

Question 6

Which parasite isn’t killed by avermectins (macrocylic lactones)?

Answer 6

Tapeworms! Was mentioned in the context of small intestinal parasites of horses

Question 7

Which ascarid of the small intestine of the horse has avermectin resistance?

Answer 7

Pascaris equorum

Question 8

Which parasite has a larval stage within the cranial mesenteric artery of the horse (colic?)

Answer 8

Strongylus vulgaris - clots break off causing blockage of blood to gut wall and this leads to necrosis and colic in large intestine

Question 9

Which parasite of the cecum and colon of horses leads to a disease similar to that of Type II (Winter) Ostertagiasis?

Answer 9

Cyathostomes (the small strongyles) diarrhea due to arrested larvae in the bowel wall - disease due to synchronous emergence of large numbers of larvae

Question 10

What parasite family of horses now has resistance to avermectins, causing egg reappearance periods (post treatment) to decrease?

Answer 10

Small strongyles (cyathostomes) - need to treat with anti-inflammatories

Question 11

Which parasite of pig doesn’t have a good drug to treat it?

Answer 11

Cystoisospora suis

Question 12

Describe the disease manifestation of Ascaris suum? (of pigs)

Answer 12

Intestinal parasite (roundworm) - causes general stunting, thickening of bowel wall, general unthriftiness (Liver and lung migration can lead to liver “milk spots” and lung “thumps”)

Question 13

Whats the name of the cattle esophageal worm?

Answer 13

Gongylonema (looks like ribbon candy)

Question 14

What should you do first with any sheep on PE?

Answer 14

FAMACHA scoring guide to check for anemia at the eye!