Parasitology Flashcards
What are the 2 types of parasites?
- Internal (Endoparasites).
- External (Ectoparasites).
What are the 4 most common ectoparasites?
- Fleas.
- Flies.
- Ticks.
- Lice.
What are the 4 most common types of endoparasites?
- Nematodes (Helminth).
- Cestodes (Helminth).
- Protozoa.
- Trematodes (Helminth).
What do fleas cause in animals?
Pruritus.
What is it called when an animal has a severe reaction to a flea infestation?
Flea Allergic Dermatitis.
Where does flea allergic dermatitis occur in dogs?
Starts at the base of the tail and progresses to the hind limbs.
Where does flea allergic dermatitis occur in cats?
Starts at the neck and progresses down the back. Called milliary dermatitis.
What are the two most common flea types encountered in domestic animals?
- Ctenocephalides felis.
- Ctenocephalides canis.
What are 4 zoonotic diseases fleas transmit?
- Yersinia pestis.
- Rickettsia felis.
- Dipylidium caninum.
- Bartonella henselae.
Why are flea infestations difficult to eliminate?
The flea lifecycle occurs both on and off the host.
What are 3 examples of ectoparasitic flies?
- Horn flies-cows.
- Stable flies-horses.
- Sheep nose bots.
What do stable flies do to horses?
- Suck blood.
- Act as a major irritant.
- Transmit EIA and Staph. aureus.
What do sheep nose bots do to sheep?
Irritate the sheep by laying larvae in the nasal passages.
What type of tick is in the Amblyomma genus?
Lone star tick.
What type of tick is in the Dermacentor genus?
Brown dog tick.
What disease does the brown dog tick vector?
Babesia caballi or Equine piroplasmosis.
What type of tick is in the Ixodes genus?
Black-legged tick.
What diseases does the black-legged tick vector?
- Lyme disease.
- Ehrlichia.
- Anaplasmosis.
What types of tick are part of the Rhipicephalus genus?
- Subgenus Boophilus: Eradicated in the U.S., but surveillance is constantly occurring.
- Subgenus Rhipicephalus: Brown dog tick.
What diseases does the brown dog tick vector?
- Anaplasmosis.
- Babesia.
- Rickettsia.
- Ehrlichia.
What type of tick is part of the genus Ornithodoros?
Soft-shelled ticks.
What disease does genus Ornithodoros vector?
African Swine Flu (ASF).
What is unique about lice among other species of ectoparasites?
They are species-specific.
What are the 2 types of lice?
- Sucking.
- Chewing.
What are louse eggs called?
Nits.
Where are nits found?
Close to the surface of the skin.
What does a louse infestation/pediculosis result in?
- Blood loss.
- Weight loss.
- Hair loss.
- Decreased milk production.
- Decreased weight gain.
What are the four types of mange?
- Chorioptic mange.
- Otodectic mange.
- Demodectic mange.
- Sarcoptic mange.
What are the characteristics of sarcoptic mange?
- Pruritic.
- Contagious.
What are the characteristics of demodectic mange?
- Non-contagious.
- Non-pruritic.
What are the characteristics of otodectic mange?
- Contagious.
- Pruritic.
How have mites been minimized in cattle?
Ivermectin products.
What is the common name for cestodes?
Tapeworms.
What animals do tapeworms affect?
- Livestock.
- People.
Does tapeworm typically cause a serious disease?
No, but it can cause colic in horses.
How do dogs and cats contract a tapeworm?
By ingesting a flea carrying Dipylidium caninum.
How do horses contract a tapeworm?
Ingesting a grass mite carrying one of the three tapeworm species that infect horses.
What is the most well-known sign of a tapeworm infection?
Proglottids (“grains of rice”) in the feces and on the perineum.
How big are helminths?
Normally are macroscopic.
What are the 3 types of helminths?
- Roundworms.
- Whipworms.
- Hookworms.
What are the 3 common types of roundworms?
- Ascaris spp.
- Dirofilaria imitis (Canine Heartworm).
- Parascaris equorum (Equine roundworm).
What is the most common type of whipworm?
Trichuris spp.
What are the 4 most common types of hookworms?
- Strongyles (Large and small).
- Ancylostoma caninum (Canine hookworm).
- Ostertagia.
- Haemonchus.
What are the symptoms of a nematode infection?
- Vomiting.
- Diarrhea.
- Poor condition.
- Unthrifty condition.
- Blood loss-anemia.
- Protein loss-bottle jaw.
What are the two symptom of lung worms?
- Moderate, dry cough.
- Slight tachypnea.
What are the symptoms of heartworm?
- Coughing.
- Exercise intolerance.
- Fainting.
- Failure to grow.
- Labored breathing.
What is the common name for trematodes?
Flukes.
What animal serves as an intermediate host in fluke lifecycles?
Snails, usually the aquatic variety.
What animals does genus Fasciola spp. affect?
- Ruminants.
- People.
- Camelids.
How do cattle do with liver fluke infections?
They are often asymptomatic.
How do sheep and goats handle liver fluke infections?
Can be fatal.
What two bacteria can complicate a liver fluke infection?
- Clostridium novyi (Black disease)
- Clostridium haemolyticum (Red waters)
What type of liver fluke is Dicrocoelium dendriticum?
Lesser liver fluke.
What are 2 common protozoa?
- Giardia.
- Coccidia.
What animals does giardia infect?
- Dogs.
- Cats.
- Pigs.
- Ruminants.
What does giardia cause (besides giardiasis)?
Diarrhea.
Is giardia zoonotic?
Yes.
What are some examples of protozoa that are coccidia?
- Eimeria spp.
- Toxoplasma gondii-zoonotic.
- Cryptosporidium spp.-zoonotic.
- Isopora spp.
What is the primary helminth of concern in small ruminants?
Haemonchus contortus or the Barber Pole Worm.
Where is the barber pole worm found in an infected animal?
The abomasum.
What does a barber pole worm infection result in?
- Hypoproteinemia.
- Diarrhea.
- Anemia.
Why is the barber pole worm of concern?
It is found worldwide and is highly resistant to anthelmentics.
What are the typical deworming recommendations in small ruminants?
- Utilization of FECRT to determine individual farm effectiveness.
- Treat animals based on severity of symptoms or production status based on FAMACHA.
- Use oral dewormers in combination with medications from other classes.
What are some alternative therapies for a barber pole worm infection?
- Copper oxide wire particles (Narrow margin of safety in sheep).
- Nematode trapping fungi (Nematophagus fungus)
- Sericea lespedeza (Tannin producing legume that also targets coccidia).
- Genetics (Parasite resistance is a moderately heritable trait).
What is refugia?
A population of parasites not exposed to anthelmintics for the purpose of slowing resistance and maintaining dewormer efficacy. Maintained using FAMACHA scoring, only deworming during extreme weather conditions, and leaving some animals with a low parasitic load untreated.
How often are small ruminants FAMACHA scored?
Bi-weekly.
Why do small ruminants develop edema in their jaw?
Their head is down most of the day grazing, so the fluid flows to the jaw.
How does a coccidia infection manifest in adult animals?
Asymptomatically and actively shedding it.
How does a coccidia infection manifest in young animals?
Severe illness and death.
What are the symptoms of a coccidia infection in young animals?
- Weight loss.
- Anemia.
- Inappetence.
- Fever.
- Dehydration.
- Diarrhea.
Is coccidia species specific?
Yes, in goats and sheep.
What things precipitate coccidia infections?
- Weaning.
- Stress.
- Overcrowding.
- Severe weather.
What is the ideal time to give small ruminants coccidia prevention (coccidiostat)?
4 weeks before lambing/kidding until weaning.
What are the coccidia prevention options?
- Lasalocid.
- Amprolium (corid).
- BT proteins.
How do adult cattle respond to parasites?
They develop age-related resistance.
How do young cattle respond to parasites?
They are more susceptible.
What are the parasites of concern in cattle?
- Nematodes: Ostertagia, Haemonchus, other.
- Liver fluke.
- Protozoa: Coccidia (young), Neospora caninum, cryptosporidium (neonates).
- Tapeworms.
How often are cattle dewormed?
Biannually.
When are cattle dewormed?
- Early spring when hypobiotic parasites emerge.
- Late fall/early winter after the first frost has occurred, to remove any residual parasites.
What routes is dewormer given by in cattle?
- Injectable.
- Oral (more effective due to treating the worms where they live).
- Pour-on (easier to do for large operations).
What methods are used to control flies?
- Ear tags.
- Pour-ons (RTL).
*Contains pyrethrens/pyrethroids.
What are the parasites of concern in horses?
- Small strongyles (cyathostomins).
- Parascaris spp.
- Tapeworms.
- Large strongyles (no longer an issue).
What are the minor parasites in horses?
- Gasterophillus spp.
- Oxyuris equi.
What is the general statement about roundworms in horses?
Resistant to macrocyclic lactones.
What is the general statement concerning small strongyles in horses?
Resistant to pyrimidines and benzimidazole.
What is the general statement concerning FECs in horses?
It should be done, on average, every 3 years to determine shedding patterns on a farm.
What is the primary parasite of concern in foals?
Parascaris spp.
What are the suggested deworming protocols in foals?
- Not doing targeted treatments based on an FEC.
- 4 anthelmitic treatments:
a. 1 and 2 for round worms.
b. 3 and 4 for strongyles or rounds, based on FEC.
c. One after 9 months for tapeworms.
What are young adult horses treated as, regardless of FEC?
High shedders.
How is dosing accuracy ensured?
By weighing the animal or using a weigh tape.
How often are young adult horses dewormed?
- 3-4 times a year with medications effective against cyathostomins. Which medication(s) used in determined by FECRT.
- 1-2 treatments for tapeworms.
How often are adult horses treated?
1-2 times per year with drugs that target tapeworms, bots, and cyathostomins.
What kind of shedders are adult horses considered to be?
Low.
*Given 1-2 additional cyathostomin treatments if found to be moderate to high shedders.
What factors affect how often horses are dewormed?
- Weather conditions.
- Stocking density.
What are the parasites of concern for companion animals?
- Roundworms (zoonotic).
- Heartworms.
- Whipworms.
- Hookworms (zoonotic).
What is the deworming schedule for puppies and kittens?
- 2, 4, 6, 8- pyrantel pamoate.
- Deworm for whipworms every 3 months.
What is the range of protection on heartworm preventative?
Monthly, biannual, or annual administration.
What is the range of protection on hookworm and roundworm preventative?
Monthly.
What are the concerns with flea and tick preventatives?
- All products are not the same.
- All products are not equally safe, due to some containing pyrethrins/pyrethroids.
- When treating for fleas, the environment must also be treated.
