parasites in goats

57
PARASITES AND GOATS DAKOTA GOAT ASSOCIATION STATE WIDE GOAT CONFERENCE - OCTOBER 20, 2017 SUSAN SCHOENIAN Sheep & Goat Specialist University of Maryland Extension [email protected] - (301) 432-2767 x343 www.wormx.info - www.sheepandgoat.com

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PARASITES AND GOATS

DAKOTA GOAT ASSOCIATIONSTATE WIDE GOAT CONFERENCE - OCTOBER 20 , 2017

SUSAN SCHOENIANSheep & Goat Specialist

University of Maryland Extension

[email protected] - (301) 432-2767 x343

www.wormx.info - www.sheepandgoat.com

PRESENTATION TOPICS

• American Consortium for Small Ruminant Parasite Control (ACSRPC)

• Overview

• Biology of parasites

• Anthelmintics (dewormers) 101

• Anthelmintic resistance

• Combination treatments

• Copper oxide wire particles

• Nematode trapping fungus

• Fecal egg counting

AMERICAN CONSORTIUM FOR SMALL RUMINANT PARASITE CONTROL

A group of scientists, veterinarians, and extension specialists devoted to (1) developing

novel methods for sustainable control of gastro-intestinal nematodes in small ruminants

and (2) educating the stakeholders in the small ruminant industry on the most up-to-date

methods and recommendations for control of gastrointestinal nematodes.

WEB SITEWORMX.INFO OR ACSRPC.ORG

Go-to place for information about internal parasites

Not Facebook or Google!

BLOG: https://www.wormx.info/blog

• Subscribe to WORMINFO

listserv to receive an email

when something new has

been posted to the web

site.

• To subscribe, send an

email to

[email protected].

In the body of the message,

write subscribe

WORMINFO.

LISTSERV

RECENT ADDITIONS TO WEB SITEBLOG AND LISTSERV

ONLINE FAMACHA© TRAINING

• Two members of consortium are piloting online

FAMACHA© training.

• Dr. Katherine Petersson, University of Rhode

Island

• Dr. Anne Zajac, Virginia Tech

• You view 2.5 hours of video: Integrated Parasite Control and Why and How to Do FAMACHA© scoring.

• You Make a video of yourself demonstrating your FAMACHA© technique and send to URI.

• Have follow-up with URI, if needed.

• Upon completion, receive certificate of competence and right to purchase FAMACHA© card(s).

http://web.uri.edu/sheepngoat/famacha/

COVERPUSHPULLPOP

GASTRO-INTESTINAL PARASITES AFFECTING SMALL RUMINANTS

OVERVIEW OF PROBLEM

• Gastro-intestinal parasites are the primary health problem affecting sheep and goats worldwide.

• GI parasites can be an obstacle to profitable and sustainable small ruminant production in many climates and production systems.

• Small ruminants are more susceptible to parasitism than other farm livestock

• Goats are more susceptible than sheep.

• Problem is worsened by drug resistance.

GOATS AND PARASITESWHY ARE THEY SO SUSCEPTIBLE?

• Goats are browsers or intermediate grazers.

• They rely on feeding strategies to avoid ingestion of infective worm larvae, which are found mostly in first two inches of vegetative growth.

• Unlike sheep, goats are unable to reduce establishment of infective worm larvae or to expel adult worms.

• In goats, immunity is rarely completely effective against worms.

• Exposure to worms is necessary to develop immunity; low levels are insufficient.

HOST IMMUNITY

https://www.wormx.info/riskfactors

MULTI-CELLULAR

HELMINTHS

1. Nemadodes

Roundworms

Strongyles

2. Cestodes

Flatworms

Tapeworms

3. Trematodes

Flukes

1. Coccidia

2. Giardia

3. Cryptospordia

SINGLE CELL

PROTOZOA

GOATS CAN HOST MANY DIFFERENT KINDS OF INTERNAL PARASITES.

USUALLY MAJOR

1. Haemonchus contortus

Barber pole worm

2. Trichostrongylus spp.

Black scour worm (bankrupt

worm)

3. Teladorsagia (Ostertagia)

Brown stomach worm

1. Cooperia

small intestinal

worm

2. Nematodirus

threadneck worm

3. Oesophagostomum

nodule worm

4. Bunostomum

hook worm

USUALLY MINOR

NEMATODES – ROUNDWORMS - STRONGYLES

5. Trichuris ovis

whipworm

6. Strongyloides

threadworms

7. Lungworms

8. Parelaphostrongylus

tenuis

Meningeal worm

MAJOR ROUNDWORMS

• Haemonchus contortus

Barber pole worm

• Trichostrongylus spp.

Black scour worm

• Teladorsagia (Ostertagia)

Brown stomach worm

Eggs look the same; need to hatch larvae in order to differentiate species.

Trichostrongylus/Teladorsagia are often not differentiated even when doing larvae ID.

BARBER POLE WORM

HAEMONCHUS CONTORTUS

• Anemia: blood/protein loss

Low packed cell volume (PCV)

FAMACHA© score 3, 4, or 5

• Sub-mandibular edema

“bottle jaw” swelling under jaw

• Loss of weight and condition

• Scours (diarrhea)

• Weakness

• Anorexia

• Death

• Acute haemonchosis: SUDDEN

DEATH

• Hypersensitivity of gut

Damage and inflammation of gut

Diarrhea (scours)

• Loss of weight and condition

Slow growth – poor performance

• Lethargy

• Death (sometimes)

• Additive: usually part of mixed infections

with H. contortus.

“SCOUR WORMS”

TRICHOSTRONGYLES

TELADORSAGIA

CLINICAL SIGNS (SYMPTOMS) OF ROUNDWORM INFECTION

ROUNDWORMS CAN BEHARD TO CONTROL

• Short, direct life cycles

• No intermediate host

• Ability to engage in hypobiosis

• Barber pole worm is prolific egg layer

• Goats slow to develop immunity.

• Compromised immunity of peri-

parturient female.

• Widespread and growing drug

resistance

ROUNDWORM LIFE CYCLE

HYPOBIOTIC LARVAE

Adult

worms in

GI tract

L4 larval

stage

L4 larvae in “arrested

development”

Eggs in

feces

During winter, most

larvae are in “arrested

development.” Few

larvae survive

prolonged cold. This

allows worms to

survive over winter (as

hypobiotic larvae) and

re-infect pastures

following spring.

Hypobiotic larvae is

the primary means by

which worms survive

in a northern climate.

PERI-PARTURIENT EGG RISE (PPER)

• Loss of immunity during late gestation

and early lactation; occurs from several

weeks before to several weeks after

parturition

• Well-documented phenomenon in

sheep; also documented in goats.

• With spring kidding, PPER often

coincides with hypobiotic larvae

resuming their life cycle.

• Need to have a strategy for dealing with

periparutient egg rise.

• Primary source of pasture

contamination.

COCCIDIA (EIMERIA SPP.)THE OTHER BIG PARASITE PROBLEM

• Single-cell protozoan parasite.

• Has more complex life cycle than roundworms.

• Host-specific

• Not all species are pathogenic (harmful).

• Affects lambs/kids mostly before and after

weaning.

• Sheep develop strong and lifetime immunity;

goats probably less so.

• Causes diarrhea, but not always, and general ill-

thrift

• Associated with poor hygiene and management.

https://attra.ncat.org/attra-

pub/summaries/summary.php?pub=483

PREVENTION

• Good hygiene, nutrition, and

management.

• Coccidiostats in mineral, feed, or waterNeed to feed or put in water before risk period

1. Lasalocid (Bovatec®) - sheep

2. Monensin (Rumensin®) - goats ( horses)

3. Decoquinate (Deccox®) - both

4. Amprolium (Corid®) - ELDU, OTC

• Natural control• Sericea lespedeza pellets

• Other (?)

• Amprolium (Corid®)- ELDU, OTC

• Sulfa drugs (Di-Methox®) - ELDU, Rx, VFD

Damages lining of small intestines.

Damage can be permanent (“runts”)

TREATMENT

COCCIDIOSIS

WHAT ABOUT TAPEWORMS?MONIEZIA EXPANSA

• Tapeworms are the only parasite visible in the

feces. Diagnosed by seeing segments in

feces.

• Tapeworms tend to be non-pathogenic; not

harmful, but they’re blamed for a lot, usually

no benefit to treatment (goats?).

• Lambs develop immunity at very young age.

• Tapeworms can cause mild unthriftiness and

digestive disturbances, intestinal blockages

(rare) and affect gut motility, predisposing

lambs to enterotoxemia (occasionally).

• Treat with albendazole (Valbazen®) or

praziquantel (in some horse dewormers,

ELDU)

https://www.wormx.info/tapeworms

WHAT ABOUT MENINGEAL WORM?PARALAPHOSTRONGYLUS TENIUS

• Parasite of white tail deer.

• Also called deer or brain worm.

• Sheep, goats, alpacas, and llamas are all abnormal hosts.

• Infection requires an intermediate host, terrestrial snail or slug.

• Causes various neurological symptoms.

• No diagnostic test in live animal.

• No FDA-approved or proven treatment.

• Cornell University has been evaluating treatment protocols: fenbendazole(SafeGuard®) + anti-inflammatory drugs (Dexamethasone or Banamine).

https://nydairyadmin.cce.cornell.

edu/uploads/doc_392.pdf

ANTHELMINTICS (DEWORMERS) 101

WHAT IS AN ANTHELMINTIC?

• Compound used to kill gastro-intestinal parasites (worms) without harming host.

• More commonly called wormer, dewormer or drench.

• Anthelmintics have different chemistries.

• Chemistry determines which worms they are effective against, mode of action, and withdrawal period(s).

• Anthelmintics are grouped by chemistries.

• There is cross-resistant among drugs in the same groups, having the same modes of action.

THERE ARE THREE (SORT OF 4) “CHEMICAL” CLASSES OF DEWORMERS FOR SMALL

RUMINANTS (IN THE US).

GROUP 1

Benzimidazoles

(BZ)

GROUP 2

Macrocylic lactones (ML)

GROUP 3

Nicotinic agonists

Avermectins Milbemycins Imidazo-thiazoles Tetrahydro-pyrimidines

Fenbendazole

SafeGuard®

Panacur®

Ivermectin

Ivomec®

Moxidectin

Cydectin®

Quest®

Levamisole

Prohibit®

Leva-Med®

Tramisol®

Levasol®

Morantel tartrate

Rumatel®

Albendazole

Valbazen®

Doramectin

Dectomax®Pyrantel

Strongid®Eprinomectin

Eprinex®Oxfendazole

Synanthic®

ANTHELMINTICS FDA-APPROVED FOR GOATS

1

Benzimidazoles

3b

Morantel

Fenbendazole

SafeGuard®

Albendazole

Valbazen®

Feed premix

Rumatel

Adult worms Not approved

Larvae (L4) Not approved sporadic

Hypobiotic larvae Not approved

Lungworms Not approved

Tapeworms Not labeled Not approved

Liver flukes Adult stage

Coccidia

External parasites

Persistent activity

Safety wide 10x (sheep)

pregnancy restriction

~20x (sheep)

Dosage 1.2 ml/50 lbs. 4 ml/100 lbs. Varies by product

Meat withdrawal 6 days 7 days 30 days

Milk withdrawal 0 days

EXTRA-LABEL ANTHELMINTICS FOR GOATS1

Benzimidazoles2a

Avermectins

Ivomec®

sheep drench

2b

Milbimycins

Moxidectin

Cydectin® sheep drench

3a

Levamisole

Prohibit®

Leva-Med®Fenbendazole

SafeGuard®

Albendazole

Valbazen®

Adult worms

Larvae (L4) Limited

Hypobiotic larvae Limited

Lungworms

Tapeworms Double dosage

Liver flukes Adult stage

Coccidia

External parasites Some

label for bot control

Some

Not labeled

Persistent activity

Safety wide 10x

pregnancy

restriction

20x 5x 3x

Dosage 1.1 ml/25 lbs. 2 ml/25 lbs. 6 ml/25 lbs. 4.5 ml/25 lbs. Depends on

dilution

Meat withdrawal 16 days(1 day for each additional day used)

9 days 14 days 17 days 4 days

Milk withdrawal 4 days(1 day for each additional day used)

7 days 9 days 8 days 3 days

https://w

ww

.worm

x.info

/de

worm

ers

ANTHELMINTIC RESISTANCE

https://www.wormx.info/anthelmintic-

resistance

IN WORM

• Worms develop resistance to drugs.

Can’t be killed!

Pass resistant genes onto next

generation.

• Some animals are more resistant to

parasites.

Ability to reduce parasite establishment.

Pass resistance genes onto next

generation.

IN ANIMAL

TWO KINDS OF RESISTANCE WHEN WE TALK ABOUT INTERNAL PARASITES

WHAT IS ANTHELMINTIC RESISTANCE?

• Genetic ability of a worm to survive a dose of

anthelmintic which would normally be

effective.

• Only worms that survive treatment carry

genes that confer resistance.

• Result of selection through exposure of worm

population to an anthelmintic.

• When more than 5 percent of worms are

“drug tolerant”; i.e. failure to reduce FEC by

95% or more (some say 90%).

http://www.scops.org.uk/what-is-resistance.html

ANTHELMINTIC RESISTANCE

• In the US, worms have developed resistance to

all dewormers and dewormer classes, though it

varies by geographic region and farm.

• Worse in Southeast due to increased parasite risk

and need for deworming.

• Worse on farms that frequently deworm or use

improper deworming practices.

• Most farms have resistance to at least two

dewormers; some farms have resistance to all

dewormers/classes. 0

20

40

60

80

100

Benzimidazoles Ivermectin Levamisole Moxidectin

Maryland Virginia Georgia

WHAT ABOUT RESISTANCE IN MORE NORTHERN CLIMATES?

FarmFenbendazole

%FECR

Ivermectin

% FECR

A 16 77

B 70 41

C 38 78

D 0 0

• There is growing suspicion

that the geographic range of

the barber pole worm is increasing

and that resistance to deworming

agents is on the rise.

• A pilot project in Alberta (2015)

showed that many Alberta sheep

flocks have high parasite burdens

and that ivermectin and fenbendazole

-resistant parasites may be common

in the province.

• NCAT is working with Montana State University Extension to determine

anthelmintic resistance in Montana, Wyoming, and Utah.

ANTHELMINTIC RESISTANCE IS INEVITABLE, BUT CAN BE DELAYED.

Practices that accelerate development of resistant worms

1. Frequent deworming

2. Whole flock treatments

3. Calendar based treatments

4. Treat and move strategy

5. Rotating dewormers

6. Underdosing

7. Depositing drug in mouth instead of deep into oral cavity.

8. Use of persistent activity dewormers

9. Use injectable dewormers

10.Use pour-on dewormers.

11.Use of feed dewormers*

12. Improper storage of dewormers

FECAL EGG COUNT

REDUCTION TEST

• Compare before and after fecal egg counts

from same animals.

• Old protocol compared post-treatment FECs of

treated animals vs. control (untreated) group.

• ~15 animals per drug tested

• Minimum FEC of 250 epg*, preferably higher.

• Can use individual or pooled (composite)

samples.

• Cost varies. Can learn to do yourself or send to

parasitology lab.

• Labor-intensive laboratory test that

determines resistance to all dewormers

and classes from a single pooled fecal

sample (from ~10 animals).

• Minimum FEC of 500 epg.

• Also identifies larvae: % Haemonchus

Trichostrongyles eggs look the same.

• Test done exclusively by Dr. Ray Kaplan’s

lab at the University of Georgia.

• $450 per sample

DRENCHRITE® TEST

TWO WAYS TO TEST FOR ANTHELMINTIC RESISTANCE

Animal Before After % FECR

1 1000 100 90%

2 500 25 95%

3 6000 150 98%

4 4350 250 94%

5 3000 1000 67%

6 1200 400 67%

7 1500 200 87%

8 750 50 93%

9 1100 100 91%

10 3100 200 94%

11 2900 200 93%

12 475 200 58%

13 900 100 89%

14 1100 50 95%

15 300 0 100%

Avg 1878 145 87%

Fecal egg count reduction test (FECRT)

COMBINATION TREATMENTS

Different drugs to kills same parasites.

Not different drugs for different parasites.

“THERE NOW IS VERY STRONG EVIDENCE THAT USING COMBINATION

TREATMENT IS THE BEST METHOD FOR USING DEWORMERS AND SHOULD BE

INSTITUTED ON ALL FARMS IMMEDIATELY.”

DR. RAY KAPLAN, UNIVERSITY OF GEORGIA (JANUARY 2017)

http://www.wormx.info/combinations

RATIONALE FOR COMBINATION TREATMENTS

• Most farms have resistance to at

least two of the three major groups of

dewormers; some have resistance to

all.

• At first introduction, drug efficacy is over

99%.

• Once efficacy falls below 95%, drug

resistance is present, though drug is still

useful for treatment.

• As effectiveness of dewormer decreases

(<95%), as it is used more, it provides less

and less benefit to animals.

• Below 50%, it is no longer effective as sole

treatment.

There is already resistance to Zolvix® in

other countries. Zolvix® is not sold in US.

WHY GIVE COMBINATION TREATMENTS?

• Contrary to popular belief, rotating between

dewormers will not prevent resistance from

developing. In fact, it will allow worms to develop

resistance to multiple drugs simultaneously. It is

no longer recommended.

• Research done in New Zealand has shown that

the best approach is to use several different

dewormers at one time as a combination

treatment.

• When combined with “best management

practices” (that help to maintain refugia),

combination treatments may improve drug

efficacy and result in a reversion back toward

susceptibility.

Most dewormers sold in New Zealand and Australia

are combination products (multiple drug actives in

same product); combination products are not

available in US.

HOW DO COMBINATIONS WORK?

• Unlike rotating drugs, there is an

additive effect with each drug used

in a combination treatment.

• By achieving a higher efficacy,

there are fewer resistant worms

that survive treatment.

• The sooner you start using

combination treatments the better,

as you achieve the greatest

difference in the percentage of

resistant survivors when efficacy of

dewormers is high.

Drug 1 Drug 2 Drug 3 Combo12 Combo123

80% 80% 80% 96.00% 99.20%

90% 90% 90% 99.00% 99.90%

60% 95% 98.00% 98.00%

60% 60% 95% 84.00% 99.20%

99% 99% 99.99% 99.99%

60% 60% 60% 84.00% 93.60%

50% 50% 50% 75.00% 87.50%

40% 40% 40% 64.00% 78.40%

95% 80% 20% 99.00% 99.20%

RECOMMENDATIONS FOR USING COMBINATION TREATMENTS

• Purchase and administer each dewormer separately in a

separate syringe.

• Do not mix dewormers. They are not chemically

compatible. Only veterinarians have the right to compound

medications.

• Administer each dewormer at full dose based on an

accurate weight.

• Can give one drug immediately after the other.

• Observe withdrawal period of drug with longest withdrawal

period

RECOMMENDATIONS FOR USING DEWORMERS IN COMBINATION

Valbazen® Cydectin® Prohibit®*

Goats 4 ml/50 lbs.

[9 days meat]

[7 days milk]

9 ml/50 lbs.

[17 days meat]

[8 days milk]

Depends on dilution

[4 days meat]

[3 days milk]

https://www.wormx.info/dewormers

SELECTIVE TREATMENT IS IMPORTANT.

REFUGIA MUST BE MAINTAINED!

• Do not give combination treatments to all

animals in a flock or group.

• Selectively treat clinically-parasitized animals to

maintain refugia.

• Refugia are worms that have not been exposed to

drug.

• Use FAMACHA© system, Five Point Check©,

and Happy Factor™ to determine which animals

need dewormed.

• If you deworm all animals in a flock or group,

you will simultaneously accelerate resistance to

all drugs.

FAMACHA©

• Use color eye chart to assess level (1-5) of anemia and need for deworming.

• Decision making tool for blood-feeding parasites only: barber pole worm.

• Examine 5 points on animal’s body to determine need for deworming: 1) eye (anemia), 2) jaw (bottle jaw), 3) back (BCS), 4) tail (dags), and 5) nose (nasal bots) or coat (for goats).

• Expands decision making ability to include parasites other than blood feeders, e.g. scour worms.

FIVE POINT CHECK©

DECISION MAKING TOOLS FOR MAKING DEWORMING DECISIONS

• Use performance, e.g. ADG, as a criteria for making deworming decisions.

• Could also use milk production.

• Untested for barber pole worm.

HAPPY FACTOR™

COPPER OXIDE WIRE PARTICLES (COWPS)

https://www.wormx.info/copper-oxide-wire-particles

WHAT ARE COPPER OXIDE WIRE PARTICLES (COWPS)?

• Tiny metal rods of copper oxide

(Cu2O).

• Poorly absorbed, slow release form of

copper versus copper sulfate which is

very absorbable; therefore, greater

potential for toxicity (especially in

sheep).

• Has been shown to reduce barber pole

worm infections in sheep and goats.

• Available as copper supplement

(different brands) for cattle (12.5 and

25 g) and goats (2 and 4 g). https://www.wormx.info/copper-oxide-wire-particles

COPPER BASICS

• Goats require more copper than sheep in their

diets and are less susceptible to copper toxicity.

• Copper metabolism is very complicated, with

several antagonists (interactions), including

molybdenum, sulfur, zinc, cadmium, and iron.

• Copper absorption is more important than copper

concentration in diet.

• Copper requirements have been set at 15, 20, and

25 ppm for lactating, mature, and growing goats

respectively [NRC, 2007].

• The maximum tolerable amount is unknown for

goats.

YOU CAN ASSESS THE COPPER STATUS OF

YOUR HERD

• Copper toxicity is less likely in goats, but it

can occur, as can a copper deficiency.

• Blood copper levels can be misleading

• Excess copper accumulates in liver.

• Collect liver and kidney samples for

testing.

• Frozen or chilled samples can be sent to

Michigan State University for testing.

https://www.animalhealth.msu.edu/

TIPS FOR USING COWPS

AS A DEWORMER

• Re-package cattle boluses into smaller doses, 0.5 or 1 g.

• Use the smallest dose needed to achieve effect.

• Goat boluses can also be repackaged.

• Dose based on age not weight: mature vs. young.

• Best to selectively treat animals showing clinical signs of Haemonchosis (FAMACHA© 4 or 5)

https://www.wormx.info/cowp-safety

ANOTHER COMBINATION TREATMENTVALBAZEN® + COWPs

Treatment(10-23 lambs per Tx group)

Efficacy

(%FECR)

No treatment (control) Increase

Valbazen® (3 ml/50 lbs.) 20%

COWP (2 g, Ultracruz™) 58%

COWP (2 g, Copasure®) 12%

Valbazen® + COWP 99%Similar results could be expected if

COWPs were combined with other

dewormers (e.g. Prohibit®).

USDA-ARS, Booneville, Arkansas

http://www.wormx.info/cowpcombo

THE FUNGUS MAY SOON BE AMONG US.

NEMATODE TRAPPING FUNGUS

DUDDINGTONIA FLAGRANS

• Duddingtonia flagrans is a

nematophagous fungus, meaning that it

traps, paralyzes, and consumes

parasites.

• Non-chemical, biological control of the

free-living stage of nematode parasites.

• Substantially reduces number of infective

worm larvae, including multi-resistant

larvae.

• Is fed to grazing animals. Spores resist

digestion. No effect on host animal.

Passes through into manure.

• Reduces amount of reinfection from

contaminated pasture. Interrupts of life

cycle.

www.duddingtonia.co

m

USING FUNGUS TO CONTROL PARASITES

• Not commercially available. Not yet.

• Dr. Jim Miller from Louisiana State

University (retired) has been told that

product (fungus) should be available

sometime early 2018.

• Will need to feed every day to maintain

effect.

• Cost may be issue.

• Greatest application is probably zoo

animals.

FECAL EGG COUNTING

www.wormx.info

[Consortium]

[W4: 2015 Conference]

[Fecal egg counts: uses and limitations]

QUALITATIVE

• Positive or negative. Yes or no. - or +

• Mix feces with flotation solution.

Place cover slip on meniscus. Put on

slide.

• Estimates number of eggs in a fresh sample

of manure: eggs per gram of feces (EPG).

• Mix known amount of feces (2-4 g) with

known amount of flotation solution (26-28

ml)

• Fill chambers of McMaster slide.

QUANTITATIVE

FECAL EGG COUNTS (FECS)

• You can learn to do your own

fecals or send sample to a

parasitology lab.

• Microscope (100x)

Mechanical stage helpful

• McMaster egg counting slide

• Homemade flotation solution

THREE PRIMARY USES OF FECAL EGG COUNTS

1. Determine treatment efficacy by comparing before and

after fecal egg counts from a group of animals (~n=15)

• Determine drug resistance on your farm

• Determine efficacy of alternative treatment(s)

2. Monitor pasture contamination

• How fast is pasture contamination building up?

• Determine when to move animals

3. Identify resistant and susceptible animals• Differentiate between resistance and resilience

• Need sufficient parasite challenge to get data separation (at

least 500 epg group average, 1000 epg better)

By

themselves,

fecal egg

counts are not

a good

diagnostic tool

for making

individual

deworming

decisions.

S U S AN S C H O E N I ANS H E E P & G O AT S P E C I A L I S T

U N I V E R S I T Y O F M A R Y L A N D E X T E N S I O N

S S C H O E N @ U M D . E D U – ( 3 0 1 ) 4 3 2 - 2 7 6 7

X 3 4 3

S H E E PA N D G O AT. C O M – W O R M X . I N F O

Thank you for your attention.

Questions?

Comments?

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