Parasites of Domestic Production - Sheep & Goats

Question 1

According to the Zulu review, you should treat the whole herd in ____ and everyone _____ times per year

Answer 1

fall
2-4

Question 2

What is the most pernicious trichostrongylid parasite affecting sheep and goats? It is a causative agent of _____

Answer 2

haemonchus contortus
Bottle Jaw Anemia
infections with large numbers of worms can bleed an animal to death

Question 3

T/F: Haemonchus has multi-drug resistance

Answer 3

TRUE

Question 4

Haemonchus contortus is parasitic in the _____

Answer 4

abomasum

Question 5

Haemonchus contortus are [small/medium/large] sized worms with adult worms with a single tooth in small buccal capsule

Answer 5

medium

Question 6

What is the life cycle of haemonchus contortus?

Answer 6

direct life cycle
prolific egg producer
pre-patent period ~21 days

Question 7

Haemonchus contortus larvae are sensitive to ______ and _______. Disease outbreaks predominates where?

Answer 7

desiccation & dry pastures
late spring and summer

Question 8

Haemonchus contortus is also called the _____

Answer 8

Barber Pole Worm

Question 9

What are clinical signs of haemonchus?

Answer 9

anemia (PCV <15%)
pale mucous membranes
hypoproteinemia submandibular edema (bottle jaw)

Question 10

Why are goats so susceptible for worms?

Answer 10

weren’t ever supposed to live in humid subtropical climate

Question 11

What is able to de-toxify ingested plants?

Answer 11

goats

Question 12

What are other trichostrongylid parasites of sheep and goats?

Answer 12

teladorsagia circumcincta (aka osteragia)
trichostrongylus sp. - less pathogenic
nematodirus sp.

Question 13

What are basic principles of parasite control?

Answer 13

reduce pasture contamination to prevent hazardous reinfection of grazing animals - don’t overstock and overgraze
appreciate risk of disease as function
use effective anthelmintics and know resistance status of drugs at herd-level
mixed (cross) species/alternate grazing

Question 14

What is fecal egg count reduction test?

Answer 14

fecal egg counts performed on 10% of the herd, or 6
eliminate all animals with FEC < 100 EPG

Question 15

Test question: T/F: Fecal Egg Counts can solely be used to make treatment decisions on individual animals

Answer 15

FALSE

Question 16

What is the FAMACHA scoring rubric?

Answer 16

qualitative scale for visually assessing anemia in sheep and goats
highly correlated with hematocrit and disease risk when used by trained observers
used as a practical basis for prescribing anthelminthic treatment to at risk animals

Question 17

Why is okay to let a few worms live (selective deworming)?

Answer 17

worms on most farms are moderately to very susceptible to the commonly used anthelmintics
killing som worms will relieve disease symptoms and slow infection
with strong drug selection, eventually most worms become resistant when treatment fails

Question 18

What are the benefits of selective deworming?

Answer 18

deworming of high FEC animals maintains genetic diversity (drug susceptibility) in worm population
maximize refugia for preserving drug effectiveness - portion of the parasite population not subjected to drug selection pressure
reduces pasture contamination with less out of pocket cost
allows animals to develop and maintain natural immunity

Question 19

T/F: Worm resistance is heritable

Answer 19

TRUE