Prepared for Delmarva Small Ruminant Conference: All Worms All day -- by Dr. Niki Whitley. Delaware State University, Dover, Delaware. December 9, 2017
HMCS Max Bernays Pre-Deployment Brief (May 2024).pptx
Putting It All Together
1. PUTTING IT ALL
TOGETHER
Dr. Niki Whitley
FortValley State University
Cooperative Extension
whitleyn@fvsu.edu; 478-825-6577
Thanks to Susan
Schoenian for slides and
pictures
2. Internal parasites
■ Internal parasites are the primary
health problem in goats/sheep
(they share worms)
■ Worst one is barberpole worm
(Haemonchus contortus) which
sucks blood; coccidia are internal
parasites but not worms
■ Worms are rapidly becoming
resistant (‘immune’) to
dewormers.
www.wormx.info
3. Internal parasites
■ Beware of myths/anecdotal stories about things that
help control parasites; use only trusted resources if
online (i.e. wormx.info; wormboss; University sites,
vet manuals)
■ Work with an up-to-date small ruminant veterinarian
and other small ruminant experts
■ We need to use every method we can to control
worms not just dewormers alone
4. “Whole farm” Approach
• Understand parasites
• Manage animals for their problem level
• Create clean or safe pastures
• Consider multi-species grazing
• Use pasture rest and rotation
• Consider alternative forages
• Understand the role of nutrition
• Could use zero grazing
• Use genetic selection
• Manage refugia (worms that will die when treated)
• Use multiple measures of worm infection to decide
which to deworm
5. Barberpole worm
Direct lifecycle of around 17-21 days – eggs
from animal (manure, grass), ingested by
animal, matures, eggs from animal
In the right conditions, Barberpole worm
larvae can live a long time on pasture (up to 6
months) and can go dormant in the animal for
up to 6 months.
They like to develop in warm (above 60
degrees F) and moist weather; pastures have
lower worm problems in very cold and very
hot/dry periods.
Note:The adults do NOT attach to the gut, they scratch the wall and drink the blood
from the scratch
6. Barberpole worm
When resistance (immunity) to
dewormers is discussed, this is
the parasite focused on;
controlling it mostly controls other
strongyle types
Symptoms–anemia, bottle jaw,
lethargy, weight loss (?)
Can have mixed infections with
others causing diarrhea, rough hair
coat, weight loss, etc.
Note:The adults do NOT attach to the gut, they scratch the wall and drink the blood
from the scratch
7. Who gets worms easiest?
Most likely to get worms
(more susceptible)
■ Stressed animals:
– Just weaned up to yearlings
(intact males)
– Just before/after giving birth
– Orphans/bottle babies
– Late-born (worm season)
– High-producing females
– Thin animals; Sick animals
– Geriatric animals
■ Genetic:
– Some breeds/selected animals
Less likely to get worms
(more resistant)
■ Less stressed:
– Mature (adults)
– Dry (not milking), open
or early pregnant
– Ones in good body
condition (fat)
– Pets
■ Genetic:
– Some breeds or adapted
– Selected animals
8. Management
■ Clean feed areas (used feeders)
and clean water
■ Avoid overgrazing; do not
graze below 6”/balance for
nutrition
■ Stocking rate 3-5 adults per
acre of good forage
■ Time birthing to minimize
parasite infections
9. Pasture or forage management
■ Rotate pastures (2-3 months
rest?) to keep grazing height up
and reduce worms on pasture
■ Graze susceptible before
resistant/less susceptible
■ Multi-species grazing; cattle or
horses eat and kill many
goat/sheep worms but the
worms do not hurt the horses or
(generally) the cattle
10. Pasture
Type
Cows Sheep Goats Cows +
Goats
Excellent
Pasture
1 5-6 6-8 1 + 1-2
Brushy
Pasture
0.75 6-7 9-11 0.75 + 2-4
Silvopasture 0.5-0.75 4-6 6-8 0.5 + 2-4
*Brush
Eradication
9-15 0.5 + 6-8
Stocking Rates on 2-2 ½ Acres
(based on Animal Units)
*Sheep can also be used for brush clearing though it may take longer
than for goats.
Slide by Dennis Hancock
(UGA Forage Specialist),
modified
11. Pasture or forage management
■ New pastures, those rotated with
crops/tilled or those “burned” are
“clean”
■ Removing a hay crop helps clean up
pastures
■ Allow access to browse (like woods);
80% of worms are in the first 2 inches
of forage
■ Forages with high tannin (like sericea
lespedeza) have been shown to lower
worm egg counts in feces of goats and
sheep (used as only feed source, could have
lower growth)
Birdsfoot (and Big) trefoil and chicory are tannin-containing plants
12. Nutritional management
■ Animals fed well/in better body condition can fight off
worms better; especially important in late pregnancy
■ Higher protein can reduce worm problems; feeding
some grain on pasture helps them fight worms
■ Animals raised in barns/dry lots (no grazing) have few
worm problems(could have coccidia problems if not
clean areas)
13. Genetic selection
■ Inherited! FEC has moderate to
high heritability.
■ Choose a resistant
breed/consider crossbreeding
with one.
■ Choose animals from a farm with
parasite exposure but little need
for deworming (parasite
resistant farm?) or with a good
FEC EBV.
■ Breed only animals that do not
need deworming often (or have
comparatively low FEC); 70-80%
of eggs come from only 20-30%
of the animals.
14. Breed your worms (keep refugia)
■ DO NOT
× (do not) Deworm on a regular schedule
× (do not) Deworm all animals in a group
× (do not) Return treated animals to a clean pasture
× (do not) Rotate de-wormers
Without refugia, worms
will become resistant to
dewormers very quickly.
Goal is to breed your worms so they have
genes that make them die when you deworm
them. Resistance is inevitable, but we can slow
it down!
15. Breed your worms (keep refugia)
■ DO
√ Deworm correctly (see deworming slides)
√ Deworm all new animals in quarantine with one
anthelmintic (dewormer) from all three classes of
dewormer (one after the other); make sure FEC goes
to 0
√ NEW INFORMATION presented at
wormx.info - using more than one
dewormer class every time you
deworm can slow down worm
resistance (immunity) to
dewormers
18. Three drug classes (in US)
Look for the DRUG name on the label, not the name brand
1) Benzimidazoles
Chemical name ends in '..dazole
Fenbendazole, Albendazole,
Oxybendazole
2) Macrocyclic lactones,
Chemical name ends in “-ectin”
a) Avermectins – ivermectin,
doramectin, eprinomectin
b) Milbemycins - moxidectin
3) Other (IMZ/TP; Nicotinics)
Levamisole, Morantel, Pyrantel
*Valbazen should not be used in pregnant animals (check label); do not rotate! If only
using single dewormers, use one until it no longer works!
19. Deworming
■ 3 classes: levamisole or “Other” class (i.e. Prohibit®;
Strongid®) and moxidectin (Cydectin®/Quest®) are
more likely to work in many areas, but growing
resistance, especially in Southeastern U.S
■ Do not use levamisole on dehydrated animals or those
that are not eating and do not overdose
■ It is not recommended to use feed-through
dewormers unless each animal is fed individually and
will eat their full amount
20. Deworming
■ Works best if given orally and,
FOR GOATS, at higher than
labeled dose (usually 1.5-2x;
see www.wormx.info goat
deworming chart; consult
vet).
■ Do not under-dose
(weigh/tape for dairy only)
■ Use sheep products first, then
cattle or horse
– Using pour-ons orally not
recommended
www.infovets.com/books/smrm/c/c098.htm (weigh tape use)
21. Deworming
■ Use sheep products first, then cattle or horse
– Using pour-ons orally not recommended
■ Dose on top of tongue at back
of mouth (feeding or dosing
syringe)
■ Store correctly, mix carefully
(levamisole), watch expiration
dates
■ Consider fasting overnight (-
dazaoles/-ectins); repeated
dosing (-dazoles)
Consult your vet for extra-label drug use!
22. Deworming
■ Consider using dewormers and COWP at
same time (?)
■ Use a DrenchRite test or FECRT to
determine which work on your farm (?)
■ Again, research indicates using one from all
three classes to slow resistance; if do this,
use longest withdrawal time
Consult your vet for extra-label drug use!
23. Deworming – Other Support
■ If weak and have a bad FAMACHA score:
– Take off pasture (so they do not get re-infected)
– Handling gently and house with (or beside) another
animal to reduce stress
– Feed high protein, good quality feed/hay and clean
water (move everything close to them if they cannot
get up; prop them up on sternum if down)
24. ■ Supportive therapy may also be needed for
weak FAMACHA 4 and 5 animals. Work with
your vet. Possible ideas (nothing proven):
– Iron (oral like Red Cell® or injectable)
– Vitamin K (may help with blood clotting?)
– Electrolytes (for dehydration); can use Gatorade®
/Pedialyte® type drinks to drench them if no
electrolytes available
– Oral liquid energy supplements (if off feed); examples:
karo syrup; propylene glycol; nutrient drenches
Deworming – SupportiveTherapy
25. Supplemental treatments?
■ Copper oxide wire particles- YES
■ Sericea lespedeza (lowers
FEC/cocci)
■ Pine bark (?)
■ Fungus (reduces
reinfection/pasture
contamination)
■ Copper sulfate (? – toxic)
Garlic
Pumpkin seed (variable)
Diatomaceous earth
Commercial herbal dewormers
■ New anthelmintics?
(Zolvix®?) will be a long
time to come to US, if
ever
■ Vaccine – will not be in
U.S.
■ Replace worms?
■ EBVs/DNA tests
Sheep are sensitive to copper, so care should be taken if using copper-based treatments. More information:
www.wormx.info and https://attra.ncat.org/attra-pub/summaries/summary.php?pub=216
Natural/alternative dewormers for support, but NOT to replace chemical dewormers