natural parasite control in small ruminants
TRANSCRIPT
Natural Parasite Control in Sheep and Goats
Dahlia O’BrienExtension Specialist – Small Ruminants
Virginia State UniversityMarch 10, 2016
[email protected](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
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Time (days)
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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