15 facts about the barber pole worm

To control the barber pole worm (Haemonchus contortus) in small ruminants, there are certain things you need to know.

1. The barber pole worm is the primary worm parasite that affects sheep and goats that graze in warm, moist climates.
2. The life cycle of the barber pole worm averages 21 days, but may be shorter when environmental conditions (warm + moist) are conducive to its development.
3. The barber pole worm has a direct life cycle; it does not require an intermediate host to complete its life cycle.

   

   Use a FAMACHA© card to estimate the
   level of barber pole worm infection

4. The barber pole worm can go into an arrested or "hypobiotic" state (inside of the animal) when environmental conditions are not conductive to its development (hot + dry or cold + dry).
5. The female barber pole worm is a prolific egg producer
6. The barber pole worm can strike quickly and silently, being especially deadly to young lambs and kids.
7. The barber pole worm attaches itself to the lining of the abomasum, the fourth and true glandular stomach of the ruminant.
8. The barber pole worm is a voracious blood sucker.
9. Adult (female) barber pole worms suck blood and lay eggs, whereas immature worms (L4) just suck blood.
10. The barber pole worm causes anemia (blood and protein loss) in the host animal.
11. Sometimes, the barber pole worm causes edema or "bottle jaw," an accumulation of fluid under the jaw.
12. The diagnostic test for barber pole worm is packed cell volume (PCV):  a blood test that measures the proportion of red blood cells in the blood. It is an indication of anemia.
13. A FAMACHA© card is used (in the field) to estimate the level of anemia (PCV) in an animal; thus, determine the need for deworming.
14. Fecal egg counts are used to estimate the worm load in an animal and can be used to determine efficacy of treatment or management.
15.  The barber pole worm does not cause scours (diarrhea).

There is no simple way to control barber pole worm infection in small ruminants. Effective control usually requires a combination of management practices and selective deworming with effective anthelmintics. What works on one farm may not work on another farm. What works one year may not work the next.