L24 Protozoa Intracellular Direct Life Cycle Pt 2 | Parasitology Exam 3

What are the three intracellular protozoa genuses w direct lifecycles

1. eimeria

2. cystoisopora

3. cryptosporidium

What are the causative agents of coccidiosis and cryptosporidosis

1. emeria

2. isospora

3. cryptosporidium

Which intracellular protozoa genus w direct lifecycle has zoonotic potential

Cryptosporidium spp.

What is the principal cause of coccidiosis in domestic animals worldwide

Eimeria spp.

What are common hosts and nonpathogenic hosts of Emieria spp

common in:

• ruminants

• birds

• rabbits

• reptiles

Nonpathogenic:

• horses

• pigs

Which part of the life cycle of Emieria spp.

Sporulated oocyts are infective stage

How many total sporozoites does Emieria spp. contain outside the animal

8 sporozoites = 4 sporocysts x 2 sporozoites (2 sporozoites = 1 sporocyst)

Bovine coccidiosis dz affects what life stage of cattle

<1 yr old cattle

What are the only three Eimeria spp. that causes pathogenic infection

• E. bovis

• E. zuernii

• E. alabamensis

(infection of cecum/colon)

E. bovis, E. zuernii, E. alabamensis infects what tissues in bonvine coccidiosis

cecum

colon

When and where does bovine coccidiosis occur

• dz occurs in wet seasons

• common in areas of overstocking and poor hygiene

True or False: Subclinical infection is uncommon amongst Bovine coccidiosis

False; Subclinical infection is most common amongst Bovine coccidiosis

What dz is attributed to significant economic loss in cattle infected by Emeria spp.

Bovine coccidiosis

Why are there millions of estimated loss in US and Mexico w Bovine coccidiosis

subclinical infection resulting in:

• dec feed consumption

• BW

• feed efficiency

What lifestage of sheeps are infected w Ovine coccidiosis

unweaned lambrs 4-8wks

What are the only two Eimeria spp. that infect sheep pathogenically causing Ovine coccidiosis

• E. crandallis

• E. ovinoidalis

What tissue is infected by Ovine coccidiosis

SI

How does infection occur w Ovine coccidiosis and dz spread to other lambs

• lambs becomed infected by oocysts passed by chronically infected adults

• produce massive number of oocysts that infect other lambs

What are the only four Eimeria spp. that infect goats causing Caprine coccidiosis

• E. caprina

• E. ninakohlyakimovae

• E. christenseni

• E. hirci

What tissue does Caprine coccidiosis infect

SI

In poultry coccidiosis what Eimeria spp. causes cecal coccidiosis

Emiera tenella

In poultry coccidiosis Emiera tenella causes what infection

cecal coccidiosis

What are the subclinical CS of coccidiosis across all species

dec growth

What are the subacute CS of coccidiosis across all species

• soft feces

• dull hair coat

• dec growth rate

What are the severe CS of coccidiosis across all species

• bloody diarrhea

• lethargy

• inappetence

• tenesmus (straining)

• death

True or False: CS of coccidiosis can be rectal prolaspses and secondary bacterial enteritis and pneumonia

True

Where and what spp. is winter coccidiosis reported

reported in calves in

NW USA and W. Canada in midwinter

What are the CS of winter coccidiosis in beef calves

CNS signs

• retroflexion of head/neck

• Calves dies in few days after CNS signs

• twitching

• loss of balance

What spp and lifestage does Cystoisospora infect

infect 5-14 days old

• dogs

• cats

• pigs

With extraintestinal stages (sporozoite/merozoite) of Cystoisospora, where does the stage occur in definitive hosts (dog, cat)

• mesenteric AND tracheobronchial lymph nodes

• liver

• spleen

→ definitive host (dog, cat)

With extraintestinal stages (sporozoite/merozoite) of Cystoisospora, where does the stage occur in paratenic hosts (mice,rodents)

• tissues (general)

→ paratenic host (mice, rodents)

What species exhibits extraintestinal stages (sporozoite/merozoite) of Cystoisospora in tissues

paratenic hosts

• mice

• rodent

In the pathology of Cystoisospora, where does lesions mainly occur (and occasionally occur)

mainly in jejunum and ileum

occasionally cecum and colon

What are the lesions of Cystoisospora typical of in the pathology

typical of colitis or enteritis

What are the differences of CS of Cystoisospora in puppies and kittens vs pigs

• puppies/kittens - diarrhea ± blood

• pigs - profuse yellow/white diarrhea

What are the four dx for Eimeria spp. and Cystoisospora spp.

• fecal exam

• direct saline smear - detecting of oocysts in feces

• fecal flotation zinc sulfate w centrifuge - detect cysts in semi/solid stool

• postmortem findings

What are the tx drug TOC for coccidiosis

Amprolium (corid, coccidiostat)

What are the supportive care for coccidiosis

• thiamine supplementation along w Amprolium

• IV fluids, dextrose, correct electrolyte imbalances - Ca, Mg, P, K

What can you add to feed for the prevention/control of ruminant coccidiosis (and what are the three)

Ionophores

• Lasolocid (Bovatec)

• Deconquinate (Deccox)

• Monesin (Rumensin)

What are management practices for control/prevention of ruminant coccidiosis

• avoid overcrowding

• clean calving environment

• keep calving grounds drained and dry

• minimize fecal contamination on hair coats

• feed and water troughs free of fecal contamination

What are control/prevention methods of poultry coccidiosis

• hygiene

• use of medicated feeds containing coccidiostatic drugs

• tx of affected birds w coccidiocidal drugs

• use of attenuated live vaccine

Where is cryptosporidium a concern for zoonotic potential

US and UK for humans only

What are the spp and lifestage affected by Cryptosporidium

young animals esp calves

Contamination of meat or water from Cryptosporidium leads to what in humans

food poisoning in humans

True or False: Cryptosporidium spp. produce sporulated oocysts that release their sporozoites in intestine causing asexual reproduction (called autoinfection)

True

How does Cryptosoporidium spp. cause autoinfection

sporulated oocysts release their sporozoites in intestine (instead of all in feces) causing asexual reproduction in the same host

Cryptosporidium Sporozoites invade what part of the SI

microvillous brush border of enterocytes

What parasite is the leading cause of waterborne dz outbreak in recreational water

Cryptosporidium

What is the fecal-oral transmission of Cryptosporidium spp

ingestion of oocysts in:

• contaminated recreational water

• drinking water

• food

• contact w infected person or animal

What parasite should vet students be aware when handling young calves for the first time

Cryptosporidium

What is the exception of the lifecycle of Cryptosporidium spp.

extraintestinal stages (sporozoite/merozoite) occurs in:

• gallbladder

• resp tract

• kidney

What are the CS of Cryptosporidium spp in calves

• yellow watery diarrhea

• few case reports of resp Cryptosporidiosis and CNS signs developed in 7-day old calf

• high morbidity and occasional mortality

What are the CS of Cryptosporidium spp in lamb/kids

• diarrhea and inefficient weight gain

• outbreak of diarrhea causes economic impact

What are the CS of Cryptosporidium spp in dogs

• dogs are more resistant to infection

• EXCEPT immunocompromised

What are the CS of Cryptosporidium spp in cats

• immune status is important

• anorexia

• Weight loss

What are the dx for Cryptosporidium spp

• fecal exam

• direct saline smear (oocytes in feces)

• fecal flotation zinc sulfate centrifugation (detects cysts in semi/solid stool)

• MiSeq/PCR

What is tx strategy for Cryptosporidium spp in cattle, dogs, cats AND humans

• paromomycin - cattle dogs cat

• nita-zoxanide - humans

What are the six preventions/control of oocysts of Cryptosporidium spp

1. freezing - <0degreesC for 1 day

2. heating - 73degreesC for 1 min

3. Methyl bromide

4. Ethylene dioxide

5. Hydrogen peroxide

6. 5% ammonia