Natural Parasite Control in Sheep and Goats

Dahlia O’BrienExtension Specialist – Small Ruminants

Virginia State UniversityMarch 10, 2016

dobrien@vsu.edu(804) 524-6963

Today’s Topics• Anthelmintic resistance

(AR) and it’s status in the U.S.

• Natural parasite control strategieso Pasture and grazing managemento Genetic Selection o Nutritiono Herbal dewormers (garlic, ginger,

pumpkin seeds etc.)o Copper Oxide Wire Particle

(COWP)o Condensed tannins (Sericea

lespedeza)o Others

• Take away points

Anthelmintic Resistance (AR)

• Ability of worms in a population to survive drug treatment of the animal at the standard prescribed dosage

• Internal parasites (worms) have developed resistance to all dewormers and all classes of dewormers

• No chemical treatment kills 100% of worms

• Two new classes of dewormers available in some countries (not U.S.) with resistance already reported

AR Status in U.S.

Benzim

idazo

le

Iverm

ectin

Cydec

tin

Leva

misol

0102030405060708090

100

Mid-Atlantic (33)South (46)

100%98%

82% 76%

47%

24% 24%

54%

Haemonchus contortus prevalent internal parasite on these farmsMid-Atlantic (2008 – 2009) and South (2008)

Pasture Management

• Should be the primary tool that producers use

• Very few worm larvae get higher than 2 inches from the ground on a plant

• Preventing animals from grazing below this reduces the number of worm larvae ingested

• Larvae migrate approximately 12 inches from a manure pileo Provide areas where animals

can browse and eat away from manure/higher off of the ground

• Reduce the stocking rateo Reducing the # of animalso Reducing the amount of time

animals graze

Pasture Management• Internal parasites of sheep and

goats are different from the parasites that affect other species such as cattle and horseso Cattle/horses “vacuum”

sheep/goat pastures helping to clean the pasture for sheep and goats

o Lead with more susceptible species/classes

• Provide access to browse and bioactive forages (such as sericea lespedeza)

• Provide diverse forages• Provide clean pastures for young

and other susceptible stock

Pasture Management Pasture rotation and rest is an

important factor in limiting parasite infections

Moving sheep/goats every 4 – 5 days has been shown to be effective in avoiding worm infections

When is it safe to return animals to a pasture? Depends on worm species,

temperature, moisture, forage type and individual animal immune status

When the barber pole predominates, resting pastures for 60 days has shown good results

Due to increased stocking rates, management of intensive grazing may increase internal parasite problems in sheep

Genetic Selection Animal selection is one of the

best long-term strategies for managing internal parasites

There are several breeds of small ruminants that demonstrate resistance to parasites Resistance – ability of

host/animal to limit infection (assessed by fecal egg counts)

Sheep breeds include: Gulf Coast Native St. Croix Barbados Blackbelly

Goat breeds include: Spanish Kiko Myotonic

Genetic Selection• Resistance varies among

individuals within breeds as well• The 70/30 or 80/20 rule

o 20 - 30 percent of flock shed 70 – 80 percent of the parasite eggs in a flock/herd

o Focusing deworming on susceptible animals will significantly reduce pasture contamination

o More parasite resistant animals decrease the need for deworming

o Culling parasite susceptible animals will increase flock resistance, reduce pasture contamination and decrease deworming frequency

Genetic Selection In addition to resistance,

there are some animals that are more tolerant of parasite loads than others

These animals are considered to be resilient Resilience - ability of

host/animal to withstand challenge and/or /infection (assessed by FAMACHA© and hematocrits

These resilient animals tend to always be wormy (high FEC) yet demonstrate few if any signs of parasitism (good FAMACHA scores etc.)

Nutritional Management

Good nutrition supports the immune system and makes animals more tolerant of internal parasites and possibly be more resistant

Protein – aids in rebuilding tissue damaged by worms

Minerals such as copper and zinc support a good immune system

Research has showed that ewes receiving higher levels of protein for 6 weeks prior to lambing have significantly lower fecal egg counts

Nutritional Management

• Supplementing lambs has also been shown to increase gains and hematocrits

• Legumes also provide more protein so access can help to protect your animals from internal parasites

• “Zero-grazing” – small ruminants raised on a dry lot will have less parasite issues

Herbal Dewormers• Molly’s Herbals Worm

Formula (www.fiascofarm.com)

• Hoeggar’s Herbal Wormer (www.hoeggerfarmyard.com)

• Garlic• Papaya• Pumpkin• Ginger• Others such as

wormwood and fennel

Information available is anecdotal mostly and limited research has been conducted to provide further

verification

• On-farm o Use of 1 tsp. (5 ml) garlic juice has been effective against worms in

lambs (http://www.garlicbarrier.com/2003_SARE_Report.html)

Herbal Dewormers - Garlic

• Three controlled studies (Burke and colleagues, 2009) – all animals treated onceo Experiment 1: 1.7 oz. of

garlic juice (diluted Garlic Barrier; 1:1)

o Experiment 2: 1.4 oz. of freshly squeezed garlic juice/2 – 3 bulbs of garlic

o Experiment 3: papaya (80 g/2.8 oz. diluted to 110 ml with water)

Herbal Dewormers – Garlic and Papaya

• Meat goat kids treated with 0.1 oz. /lb. body weight (Gooden, 2012) – treated every other day

Herbal Dewormers – Papaya

• Meat goat kids fed pumpkin seeds top-dressed on feed (PUM; 0.08 oz./lb.) or not (CON) every day for 21 days (Matthews et al., 2016)

• Two animals removed from PUM group due to high FEC and clinical symptoms

Herbal Dewormers – Pumpkin

Project funded by Northeast Sustainable Agriculture Research

and Education grant: Project #LNE08-269

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• Meat goat kids treated with a pumpkin seed drench (PUM; 0.08 oz./lb.), ginger drench (GIR; 0.05 oz./lb.) or no treatment (CON) every other day over a 42-day period

• At slaughter, CON group had more worms (1,857) compared to both the GIN (549) and PUM seed (869) drenched groups

Herbal Dewormers – Pumpkin and Ginger

NO animals in the PUM group displayed clinical symptoms/required deworming

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Commercial Herbal Dewormer

• Using commercially available herbal wormers can be a promising and viable alternative to chemical control

• Natural • No environmental

hazards• No need for

withdrawal periods

Hoegger’s Herbal Wormer (Hoegger’s Goat Supply, Fayetteville, GA: containing wormwood, gentian,

fennel, psyllium and quassia)

Molly’s Herbal Worm Formula Kit (Fias Co Farms: containing wormwood, black walnut and other

natural products)

• Hoegger’s Herbal Wormer (HHW) - meat goat kids drenched with manufacturer's recommended dose or not (CON) over a 35 day period

• Natural infection (>50% H. contortus)

• HHW did not reduce FEC in kids

Commercial Herbal Dewormer

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CONHHW

• Hoegger’s Herbal Wormer (HHW) - lactating meat does drenched with manufacturer's recommended dose or not (CON) over a 70 day period

• Natural infection (>62% H. contortus)

• FEC increased by 535% in the CON group and only by 182% in the HHW group by the end of the study

Commercial Herbal Dewormer

0 14 28 42 56 700

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Eight total dewormings (6/8 CON and 2/8 HHW)

• Molly’s Herbal Worm Formula Kit (Burke and colleagues, 2009)o Formula 1 – wormwood,

garlic, fennel, black walnut, and sweet weed

o Formula 2 – field pumpkin, mugwort, garlic, fennel, hyssop, thyme and sweet weed

o Dose administered according to manufacturers recommendations

Commercial Herbal Dewormer

FAMACHA© scores were higher for the herbal treated goats

No reduction in worm counts observed

• There is anecdotal evidence that herbal dewormers work• Lack of scientific support• Inconsistent data when support is available

Herbal Dewormers

**Active ingredients vary****Common names do not always refer to the same plant**

**Dose recommended not high enough to produce anthelmintic properties**

Cautious – some herbs are toxic!

Herbal products/dewormers should always be combined with other integrated parasite management techniques

Know the status of drug resistance on your farm so that these techniques can also be used in conjunction with an effective chemical dewormer

• COWP are available commercially to alleviate copper deficiency in ruminant livestocko Copper is important for immune

function• Sheep sensitive to copper –

margin of safety between the required amount of coper (10 ppm) and the toxic level (25 ppm) is very narrowo Some sheep breeds are more

sensitive than otherso Goats are less susceptible and

can tolerate up to 80 ppmo The form of copper used in

COWP is poorly absorbed, reducing the risk of copper toxicity

Copper Oxide Wire Particles (COWP)

• Multiple studies have been conducted showing that COWP (Copasure®) treatment is effective against Haemonchus contortus (barber pole worm)o Mode of action – indirectly by acting on adult worms in animals abomasum

(true stomach) due to increased copper or directly by penetrating the cuticle of the worm

• COWP can be included in an integrated gastrointestinal nematode (GIN) control program, specifically to control Haemonchus contortus

Copper Oxide Wire Particles (COWP)

• Use the smallest dose of COWP needed to achieve the desired effect

• Young – uses 0.5 to 1 gram per head

• Older/mature animals - 2 to 4 grams per head

• Use lower doses in sheep and in smaller goat breeds

• Depending on dose do not give more than 2 – 4 treatments in any one grazing season

• At least 6 weeks should elapse between treatments

Copper Oxide Wire Particles (COWP)

Condensed Tannins• Tannins are plant compounds

that bind to proteins and other molecules

• Sericea lespedeza (AU grazer™) is a high-tannin forage (4–15% DM) that has been scientifically proven to reduce parasite loads in sheep and goats

• The mechanism of action is not yet known. o By tannins reacting directly with

adult worms by attaching to their “skin”, causing them distress

o Indirectly by improving protein nutrition of the goat and boosting the immune system

• Fresh (grazed), dried (hay, leaf meal, pellets), or preserved (ensiled) forms of SL tested so far have showed some level of anti-parasitic activity against worms, particularly H. contortus

• Also effective against the protozoan parasites (Eimeria spp.) that cause coccidiosis

Condensed Tannins

• Forage chicory – the FEC of lambs grazing chicory increased less than those grazing sudangrass in Ohio (McCutcheon et al., 2012)

• Lambs grazing chicory had consistently less FEC and grew faster than lambs grazing grass/clover 

Condensed Tannins

Others – Diatomaceous Earth• Diatomaceous earth (Diatomite)

is the skeletal remains of single-cell algae, and there are claims that it can serve as an effective alternative dewormer for animals

• Diatomaceous earth has been used for many years for control of various pests

• As a deworming control it is often mixed with the mineral supplement or in the feed

• Anecdotal claimso Extends the time between dewormings o Kills worms in goats

• Scientific datao diatomaceous earth does not kill worms in

goats o One study did show that at a very high level

(5% of the diet), it had a slight effect

It is used as a food ingredient and in swimming pool filters

Others – Diatomaceous Earth• Anecdotal claims

o Extends the time between dewormings

o Kills worms in goats – 2% DE in feed kills internal parasites including tapeworms and roundworms

• Scientific datao Shown to have insecticidal

propertieso The majority of controlled

studies in sheep, goats and cattle show no significant impact on internal parasite infection

• Nematode trapping fungi (Duddingtonia flagrans), have been studied with varying results

• D. flagrans is a nematode trapping fungus that survives passage through the digestive tract of livestock, germinate and spread on fresh feces producing specialized nematode trapping structures that restrict the development of parasite larvae

• Not available in the U.S. at this time

Others – Nematode trapping fungi

Successfully applied under field conditions with cattle,

sheep and goats

• Australia has developed a strain of D. flagrans that provides control at a dose of 30,000 spores/kg body weighto Previously doses of up to 1,000,000 spores/kg body weight has

been used in kids and lambs• Expected that this will be available as a feed additive in

Australia the near future

Others – Nematode trapping fungi

• Haemonchus (barber pole worm) vaccine is commercially available in other countries for sheep (lambs only)

• Might “never” be available in the US o It is very costly to makeo Supply is limited (into the near

future) even though demand is high

o Not enough sheep in the US

• Other types of vaccines are being investigatedo Not sure if any are being

developed for the market

Others – Vaccine

Take away points They should always be combined with

other integrated parasite management techniques

Sericea lespedeza and copper oxide wire particles are two effective natural deworming products that can be incorporated into an integrated/sustainable control program for worm control in sheep and goats

There is strong evidence that anthelmintic resistance has reached critical levels throughout the entire Eastern United States

Sustainable integrated parasite management (SIPM) practices must become the new standard

Most scientific studies have found that natural products fail to reduce worm counts in sheep and goats

Herbal products alone should not be relied on for controlling/treating internal parasites

It is important to know the status of drug resistance on your farm so that these techniques can also be used in conjunction with a more targeted and strategic manner of deworming following the principles of

‘Smart Drenching”

Thanks for you attention