Chapter 17
Parasites
Dr. Dipa Brahmbhatt VMD, MPH, MS
Objectives
•
•
•
•
ID Common endoparasites in small ruminants
Clinical signs associated with parasites
Diagnosis
Treatments
Reading Assignment
Chapter 17: Common Ovine and Caprine
Diseases
Know table 17 -3: Parasites
Key terms
•
•
•
•
•
•
•
Fecal flotation
ELISA
Baerman technique
Skin scrapings
Pre patent period
Direct life cycle
Indirect lifecycle
Figure 6-61 Baermann apparatus is used to recover larvae of roundworms from feces, soil, or animal tissues. This apparatus is most
useful in recovering larvae of lungworms.
(Reprinted from Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Abomasum
Family: Trichostrongyloidea
Haemonchus Contortus
• Haemonchus contortus – barberpole worm/
wire worm
PPP: 17 – 21 days
– 1” (25 mm)
– Abomasum of
Male bursa RIght
small ruminants
– feeds on blood
– Clinical signs
• anemia, bottle jaw, chronic weight loss
• death
Clinical signs Haemonchus
• ‘bottle jaw’:
hypoproteinemia
and anemia.
• usually late
winter.
Figure 6-34 Characteristic trichostrongyle-type ova of the bovine trichostrongyles. These oval, thin-shelled eggs contain four or more
cells. They measure 70 to 120 µm long. Some of these ova can be identified by their respective genus; however, identification is
usually difficult because mixed infections are common.
(From Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Adults in the abomasum.
Barberpole worm
TX: Levimasole, ivermectin, doramectin,
Moxidectin, albendazole, morantel tartate,
eprinomectin, tetramisole
Ostertagia ostertagi
• Ostertagia ostertagi (brown stomach worm)
– 1/2” (10 mm) adult worm; abomasum
– most serious impact on calves
– disrupt gastric acid secretion
Male bursa left
– Clinical signs
• diarrhea
• ill‐thrift
• poor feed conversion
PPP: 16 – 23 days
Ostertagia ostertagi
TX: Fenbendazole, ivermectin, doramectin,
morantel tartate, moxidectin
Trichostrongylus axei
• Trichostrongylus axei
– “Bankrupt worm”
– Small stomach worm
TX: Fenbendazole, ivermectin,
doramectin,
Moxidectin, albendazole, morantel
tartate, eprinomectin
– Adults ~1/4” (4‐8
mm); abomasum
– Clinical signs
–
–
–
–
Diarrhea
dehydration
bottle jaw
emaciation
PPP: 21 days
Small Intestine
Nematodirus
• Nematodirus spp.
– “Thin necked
intestinal worms”
– N. battus is more
pathogenic
– SI
– Diarrhea, Anorexia
TX: Fenbendazole, albendazole,
ivermectin, Moxidectin, albendazole,
morantel tartate, levamisole
B = typical strongyle egg
PPP: 14 - 21 days
Figure 6-35 Characteristic large ova of Nematodirus species. In standard fecal flotation, the eggs of Nematodirus species are larger
than those of other bovine trichostrongyles (150 to 230 µm by 80 to 100 µm), have tapering ends, and have four to eight cells.
(From Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Strongyloides papillosus
•
•
•
•
Family: Rhabditodea
Threadworm
CS: foot rot, diarrhea
TX: eprinomectin,
ivermectin
• ZOONOTIC
PPP: 1 – 2 weeks
Trichostrongylus Colubriformis
• Hair worm, black scour
worm
• CS: diarrhea, +/bottlejaw, dec. weight
gain,
• PPP: 21 days
• ZOONOTIC
TX: Fenbendazole, doramectin,
Moxidectin, morantel tartate,
eprinomectin
Figure 6-36 Characteristic ova of Moniezia species. The eggs of Moniezia expansa are triangular or pyramidal and 56 to 67 µm in
diameter. The eggs of Moniezia benedini are square or cuboidal and approximately 75 µm in diameter.
(From Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Cooperia spp.
• Cooperia punctata or
pectinata
• Cattle bankrupt worm
• CS: decreased growth
and anorexia
• PPP: 21 days
TX: Fenbendazole, Levimasole, ivermectin, doramectin,
Moxidectin, albendazole, morantel tartate,
eprinomectin
Bunostomum trigonocephalum
• Trichostrongloidea
– Bunostomum
trigonocephalum:
– hookworms
– Larger than strongyle
eggs
– Diarrhea, anemia,
weight loss, death –
young animals
– PPP: 2 months
Courtesy of Dr. Dietrich Barth, Merial
TX: Fenbendazole, ivermectin,
doramectin,
Moxidectin,
eprinomectin
Monieza expansa
• CESTODES
– Monieza expansa
• Not very pathogenic
• PPP: 40 days
TX: Fenbendazole, albendazole,
dichlorophen, lead, arsenate,
niclosamide
Moniezia expansa,egg. Courtesy of Merial
Cecum and Colon
Oesphagostomum columbianum
– Strongylidae
• Oesphagostomum
columbianum:
nodular worm
• cecum, colon
• anorexia; severe,
constant, dark,
persistent, fetid
diarrhea with fly
strike; weight loss;
and death
• Adults: cysts in GI
• PPP: 40 days
Oesphagostomum columbianum
TX: Albendazole, Eprinomectrin,
Moxidectin, Doramectin, albendazole,
morantel tartate, levamisole
Oesophagostomum gross lesions (nodules), abomasum, sheep.
Courtesy of Dr. Raffaele Roncalli
Chabertia ovina
• Large bowel worm
• CS: anemia
• PPP: 2 months
TX: Albendazole, Fenbendazole,
ivermectin
Trichuris ovis
• Whipworm
• CS: hemorrhage –
cecum with fatal
infections
• PPP: 2 months
TX: Eprinomectin, Fenbendazole,
ivermectin
Lung worms
Dictyocaulus filaria
• Lungworm
• CS: cough, cyanosis,
dyspnea
• PPP: 28 days
• Baerman technique
TX: Ivermectin, Eprinomectrin,
Moxidectin, Doramectin,
fenbendazole, levamisole
Figure 6-38 Representative eggs and larvae of Dictyocaulus species, or cattle lungworms.
(From Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Protostrongylus
• Protostrongylus rufescens,
P. rushi, P. stilesi
• Bighorn sheep lungworm
• Transmission:
transplacental, snails
• CS: predisposes to
pneumonia
• PPP: 35 days
• DX: Fecal baerman
• Flukes: liver and bile
TX: ivermectin, albendazole, fenbendazole
Muellerius capillaris
• Goat lungworms
• May predispose to
pneumonia
• Baerman techniique
• snail
TX: ivermectin, albendazole, fenbendazole
Figure 6-39 First-stage larva of Muellerius capillaris, the “hair lungworm” of sheep and goats. First-stage larvae are 230 to 300 µm
long. The larval tail has an undulating tip and a dorsal spine.
(From Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Liver
Fasciola hepatica
• Fasciola hepatica
• Liver flukes
– Live in bile ducts as adults
– Aquatic snails =
intermediate host
– CS: anemia, weight loss,
decreased performance,
hepatitis, death
• PPP: 10 – 12 weeks
–Eggs: are heavy
sedimentation is
recommended
TX: Clorsulon, nitroxynil,
rafoxanide
ZOONOTIC
Figure 6-37 Characteristic operculated ovum of Fasciola hepatica, the liver fluke of cattle, sheep, and other ruminants. The eggs
measure 140 by 100 µm and are yellowish-brown and oval.
(From Hendrix CM, Robinson E: Diagnostic parasitology for veterinary technicians, ed 3, St Louis, 2006, Mosby.)
Thysanosoma actinoides
•
•
•
•
•
•
•
Fringed tapeworm
Sheep
CS: weight loss
Liver condemned
PPP: 30 days
Dx: proglottids – feces
Tx: Fenbendazole and
albendazole
ID necropsy
•
•
•
•
Taenia hydatigena
Echinoccocus granulosus
Taenia ovis
Taenia multiceps
References
• Large animal clinical procedures for veterinary technicians,
Elizabeth A. Hanie, 2006
• http://www.caes.uga.edu/publications/pubDetail.cfm?pk_ID=
6196
• http://courses.cals.uidaho.edu/avs/avs471/Lectures/Lectures
%202010/Lecture%20Parasites%20notes.pdf
• http://cal.vet.upenn.edu/projects/dxendopar/parasitepages/t
rematodes/Fhepatica.htm
• http://cal.vet.upenn.edu/projects/dxendopar/index.html#feca
l
• http://www.sheepandgoat.com/HairSheepWorkshop/parasiti
sm.html
• http://cal.vet.upenn.edu/projects/merial/Nematodes/Table1.
htm
References
• http://www.vetmed.wisc.edu/pbs/vetpara/tutorial2.html
• http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/
bc/toc_22400.htm
• http://instruction.cvhs.okstate.edu/jcfox/htdocs/clinpara/lst4
1_50.htm
• http://instruction.cvhs.okstate.edu/jcfox/htdocs/clinpara/lect
ure.htm
• http://cal.vet.upenn.edu/projects/merial/index.html
• Laboratory procedures for Veterinary Technicians, 5th edition,
2007, Hendrix C.M; Sirois M.
• K Holtgrew-Bohling , Large Animal Clinical Procedures for
Veterinary Technicians, 2nd Edition, Mosby, 2012, ISBN:
97803223077323
References
• http://wwwnc.cdc.gov/eid/article/17/7/101519-f1.htm
• http://www.extension.org/pages/19680/goatother-parasites