Presentation on theme: "Integrated Parasite Management for Small Ruminants"— Presentation transcript:
1 Integrated Parasite Management for Small Ruminants Slides contributed by Marguerite Frongillo, Steve Hart, Susan Schoenian, Mary Smith DVM and tatiana Stanton
2 Know your weapons Effective management Effective drug use Effective surveillance
3 Integrated Parasite Management (IPM) Goal is not to create parasite-free animals. It is normal for sheep and goats to have parasites. Goal is to prevent clinical disease and production losses.
4 Parasite control begins with good management and common sense Good sanitationFeeders which prevent wastage and contamination.Clean water, free from fecal matter.Not overstocking pens and pastures.Isolation and deworming of new animals in an area where you can retrieve their manure easily.
5 Pasture Management to reduce barber pole worm problems Use clean or safe pastures – easy to say, difficult to implement for entire grazing cycleUse multispecies grazingUse alternative foragesMake wise management decisions about pasture height, pasture rest, and pasture rotation
6 Use “clean or safe” pastures What is a truly safe pasture?New pasturePasture that has been renovated with tillageA pasture that has not been grazed by sheep or goats for the past 6 to 12 months – however, worm population does start to drop sharply after 2 months.Pasture grazed solely by horses and/or cattle for the past 6 to 12 months.Pasture in which a hay, baleage or silage crop has been removed.Pasture that has been rotated with row crops.Burnt pasture
7 Dilute worm population by grazing multiple species Sheep and goats share the same internal parasites, but they are different from the parasites that generally affect cattle and horses.Cattle and horses “vacuum” sheep/goat pastures.Other benefits complimentary grazing habits.
8 Is this multispecies grazing? Is it going to be helpful?
9 Alternative foragesLivestock that browse have fewer parasite problems (excepting deer worm).Livestock grazing tall-growing forages will have less parasite problems.80% of parasites live in the first 2 inches of the vegetation.Grazing high-tannin forages may reduce the effects of parasitism.
10 Forage ChicorySericea LespedezaBirdsfoot TrefoilPure stands of chicory, birdsfoot trefoil, and Sericea lespedeza have been shown to reduce fecal egg counts and/or larval development.
11 Hayfield Regrowth is a safe pasture alternative in late summer and fall
12 Pasture Height – 80% of the internal parasites found in bottom 2 inches of vegetation Not a big concern during first pass through your rotational pastures after winter . Big concern in later passes.
13 In a grazing system for small ruminants we are: Generally trying to move animals before the pasture is below 3 inches and get back in before pasture gets too mature
14 Too high and mature high lignin less nutritious and palatable for small ruminants trampling losses , etcetera
15 Problems with intensive rotational grazing and small ruminant parasites - In a rotational grazing system with the primary purpose of controlling worm populations, sheep/goats should not be returned to the same pasture for at least 45 to 60 daysThis conflicts with the use of intensive rotational grazing to increase the nutritional off-take from a pastureDue to increased stocking rates and rapid grazing intervals, management intensive grazing may increase internal parasite problems in sheep and goats as the grazing season progresses.
16 In summaryIf animals are left in a grazing paddock for longer than 5 to 10 days, depending on weather, may be exposed to infectious larvaePasture rest periods to control internal parasites need to be longer than normal recommendations for either pasture health or nutritional value
17 Things to consider when using intensive rotational grazing Are there safe pastures that animals can be moved onto as grazing season progresses?Brush pasturesHayfield regrowthPastures that your cattle or horses have been grazingCrop stubble or seeded annualsCan you disrupt the worm cycle by mowing the pasture extremely short, grazing other species, or harvesting a crop of hay or baleage before resuming grazing?
18 Rotational grazing in the spring appears to reduce the “barnyard effect” and delay the onset of summer parasite problems
19 Barnyard Effect Barnyards with grass or other good forage Lead to high concentration of manure and internal parasites in grazing material Can contribute greatly to herd contamination with internal parasites May have a “barnyard effect” in pastures that border barn and are not rotated
20 Manure pile right in yard – kids born late April – barn situated in very large pasture but kids and does tend to graze right by barn where manure concentration (and worm contamination) is highest. By late July kid loss to worms and coccidia
21 Please note that we are talking about herds that are rotating in the spring and summer and that by late July most of these also had high worm loads2375035752250
22 Goats free range on woodlands during the day and locked in very large compound 5 pm to 8 am compound seeded to pasture in 2004herdsman noticed in Spring 2005 that kids did not go to woods with dams, instead stayed & grazed at compound kid loss by mid July to worms and coccidia.
23 Please note that we are talking about herds that are rotating in the spring and summer and that by late July most of these also had high worm loads188751003700
24 Central graining and watering areas can also have a barnyard effect
25 On these two farms, shelter and grain troughs move with the herd from pasture to pasture eliminating barnyard effect
26 Some options to help reduce barnyard effect – Can you implement any of them? make barnyard small enough that very little forage presentlay down gravel, concrete, or herbicidesclose off access to barnyard during day and on full moon nightsprovide hay in barn at night when animals come in from pasture to cut down on night grazing in the barnyardreplace barnyards with narrow lanes from pastures to barnleave animals in rotated pastures 24 hours a day with portable shelter, water and feeders
27 “Zero” grazingSheep/goats raised in confinement or dry lot (with no grass) have fewer stomach worm problems.Sheep/goats put in confinement or dry lot do not usually get re-infected with stomach worms.Coccidiosis could be more of a problem in confinement.
28 One farm’s forage management strategy to control worms hay feeding 30 Boer X breeding does from mid Dec through April. Herd kids in April and adult does wormed May1st.rotational grazing of conventional pastures (6 acres) from May through July, goats stay on each area ~1 wk before rotating to next pasture – returned to each pasture in ~ 45 days. Horses follow 2 weeks after goats in most fields. Individual animals are wormed as needed. Entire herd wormed at end of July at weaning.
29 Management Strategy continued month-long grazing of two brush pastures Aug through Sept (3 acres). Individuals wormed as needed. In 2006, entire herd fasted and wormed with 2 wormers for deer worm in October – wormers used are ones that barberpole worm already shows resistance to in herdstrip grazing of hay field regrowth from Oct until mid Dec (7 acres), animals moved to new strip every 5 to 9 days and never repeated on same strip. Individuals wormed as needed. Some years entire herd wormed Dec 15, some years entire herd wormed March 15th, some years neither worming necessary and only a few individuals wormed
30 Nutritional Management Animals on a high plane of nutrition and in better body condition are better able to withstand worm burdens.Nutrition in early pregnancy (fat stores) can affect the immune response to internal parasites.Sheep receiving higher levels of protein prior to lambing have lower fecal egg counts.
31 Immune Response Good nutrition stimulates immune system Can select goats and sheep for low fecal egg countsOther diseases which depress immune system (e.g. coccidiosis, Johnes) can cause increased worm problems
32 Immune ResponseWhen goat/sheep are lactating, immune system is suppressed and does not fight parasites. Arrested larvae acquired during the fall all mature simultaneously in the spring during lactation. Rationale for deworming before kidding.Protein consumption at 130% of daily requirements reduced flush of egg laying at parturition in sheep
33 Genetic ManagementTry to select for “resistant” animals
34 “Resistant” Breeds Some sheep and goat breeds are more resistant to worms. Gulf Coast NativeHair sheepBarbados BlackbellySt. CroixKatahdinDorper (?)Royal White (?)NOTTraditional wooled breedsGoatsPossibly –Spanish/BrushMyotonic/TennesseePygmyKiko (?)NOTBoer goatsDairy goatsAngora goatsSavanna????
35 “Resistant” Individuals Parasite resistance varies between individual animals of the same breed type.20-30 percent of flock shed most of the parasite eggs.Focusing deworming on susceptible animals will significantly reduce pasture contamination.BUT - Lactation and weaning are examples of environmental effects that render an animal more worm-susceptible.Culling worm-susceptible animals that have no environmental excuse for being “wormy” should increase flock resistance and reduce pasture contamination.
36 A valuable, limited resource that must be managed properly. DrugsA valuable, limited resource that must be managed properly.
37 Three drug families Benzimidazoles Nicotinics Macrolides Avermectins Chemical name ends in '..dazoleFenbendazole, Albendazole, OxybendazoleNicotinicsLevamisole, Morantel, PyrantelMacrolides AvermectinsIvermectin, DoramectinMoxidectin
38 Benzimidazoles – “white drenches” Fenbendazole – SafeGuard® or Panacur®Albendazole – Valbazen®Oxyfendazole – Synantic ®Broad spectrumWide margin of safetyEffective against tapewormsValbazenEffective against adult liver flukes.Should not be administered to pregnant animals.
39 NicotinicsRumatelOral feed additiveOnly effective against adult wormsPyrantelLevamisoleBroad spectrumEffective against arrested larvaeNarrower margin of safety, especially injectable productLevamisole - (clear drench). Tramisol ®, Levasole®, Prohibit®Morantel– Rumatel®, Positive Goat PelletPyrantel - Strongid®
41 Extra-label drug useOnly Fenbendazole (SafeGuard®) and Morantel (Rumatel®) are FDA-approved for goats.Only Albendazole (Valbazen ®), Ivomec ® drench, and Levamisole (drench and bolus) are FDA-approved for sheep.Use of a product that is different than its label constitutes extra-label drug use and requires a veterinary prescription in context of valid veterinarian-patient-client relationship.Should use exaggerated withdrawals when using drugs extra label (keep records). Check with
42 Non-chemical dewormers – not yet! Botanical dewormers - herbsDiatomaceous earth (DE)No scientific studies have shown DE or other non-chemical treatments to reduce fecal egg countsMany natural “dewormers” would have to be given at toxic levels in order to be effectiveGarlic juice has shown promise?OtherTannins, fungusCopper boluses (goats)vaccine
43 Epazote Study1) Oil of Chenopodium administered in gel capsules at a rate of 0.15ml/kg body weight is ineffective in reducing the number or viability of internal parasite eggs in NY sheep and goats. Higher dose toxic to host animal.A commercial organic worm discourager and a soluble soap, Basic H, were equally ineffective.
50 Lungworms Indirect or direct life cycle Severe infestations cause coughing, fluid in lungs, pneumoniaTransmitted in fecesTake fecal sample direct from animal (otherwise can confuse with soil nematodes)Same control program as stomach and intestinal worms.
51 TapewormsPasture miteLife CycleWorms live in small intestines.Eggs pass out through feces.The egg is eaten by a pasture mite.The egg hatches.The mite is eaten by the sheep or goat.Light loads of tapeworms tend not to be a problem, but severe infestations can cause problems.
52 Coccidia Eimera sp. (species-specific) Single-cell protozoa that damage lining of small intestines.Can cause bloody diarrhea that may be smeared with mucousDamage can be permanent!Prevent with good sanitation and proper stocking
53 Coccidiosis Suspect when animals get diarrhea after 3 weeks of age “mucky butt” in lambsmany Eimeria species, host specific, variable pathogenicityimmunity to each species of coccidia develops with exposurewarmth and moisture permit sporulationFrom Egg to infectious 1-2 days but easily survive 2-3 mo and can survive 1 year in optimum conditionsKilled by direct sunlight and low humidity (<25%)
55 Severe coccidiosis in goats/sheep causes many small white foci in the intestinal wall – absorption impaired
56 Fecal exams for coccidia may have 10,000 or 100,000 per gram without diseaseEgg count drops only for a short time after treatment then reboundsnone in older animal? You didn’t look!
57 Coccidiosis raise dairy kids away from adults If possible, separate lambs and kids by age, ideally only a 2 weeks spread in age in a groupmilk is protective, weaning precipitates diarrheacoccidiostats in the milk and starter feed – decoquinate, monensin, lasalocid
58 Can use coccidiostats as additives in the feed, salt or water to help prevent: Especially in pregnant females starting 1 month before parturition until weaning of their young. Continue in young animals after weaning.Lasalocid (Bovatec®)1,3Monensin (Rumensin®)2,3Dequinate (Deccox®)1,2Amprolium (Corid®) in water1 - FDA-approved for sheep2 - FDA-approved for goats 3 - TOXIC to EQUINES!!!!!!
59 Sanitation – clean and dry keep kids and lambs out of feeders !
60 Treatment of coccidiosis oral sulfonamides –Sulmet, Albon, etc.amprolium mg/kg per day for 5 days = 1 ml Corid 9.6% per 8 poundscan add to milk or directly drenchtreatment temporarily decreases shedding but does not eradicate parasite – rebound in oocyst countadequate selenium for immunity
61 Meningeal worm (deer, brain worm) Parelaphostrongylus tenuis Parasite of White Tail DeerSmall ruminants are an abnormal host (sheep, goats, llama, alpaca)Parasite has indirect life cycle – snails and slugs needed for infection
62 Animals maintain appetite Larva travel from intestinal tract to spinal cord to brain, causing Nerve damage (can include lameness, gait abnormality, itching) can be as extreme as paralysis or even DEATH Animals maintain appetite
65 Differential diagnoses CAE, OPPfracture, vertebral body abscesscopper deficiencytail docking infectionfoot rot, white muscle diseaselisteriosisPolio-encephalomalaciabrain abscessrabiesscrapie
66 Treatment of P. tenuis in aberrant hosts no controlled studiesescalation of drug dosagesivermectin 0.2 to 1.0 mg/kg for 1-5 dfenbendazole 10 to 50 mg/kg for 1-5 dusually both simultaneouslyanti-inflammatories importantcorticosteroids if not pregnant: dexamethasone 0.1 mg/kg s.i.d. for 3-5 dflunixin 1 mg/kg s.i.d. or b.i.d. for 3 d
67 Prevention of exposure do not pasture at edge of woods especially during wet seasonavoid low-lying poorly drained fields except under very dry conditionsfence off deer watering spotsuse fields deer prefer for hay, not grazingguardian dog may helptake advantage of hunting season!
68 Prophylaxis in aberrant host for camelids, probably not for sheep and goats (Haemonchus resistance)injectable ivermectin q 4-6 wk pour-ons? (not sheep or goats)newer avermectins with longer duration?fenbendazoledaily pyrantel not effective
69 Liver flukesSome farms in NE US have acute or chronic liver fluke populationsRequires open water, snails (wet conditions)Can kill adult liver flukes with Albendazole (Valbazen®) or Ivomec® Plus)
75 Fascioloides magna American deer fluke natural parasite of deer and elksheep and goats abnormal hostslarval stages continue to migrate through liver - sheep and goats don’t excrete eggsACUTE disease - usually fatal within 6 months