Parasitology II LA protozoa

how many sporocysts does Eimeria have?

4

how many sporozoites is in one Eimeria oocyst?

8

ID

Eimeria

what is the flat part on the top of some Eimeria oocysts?

polar cap

what are the highly pathogenic species of Eimeria in cattle?

zuernii and bovis

what are the moderately pathogenic Eimeria species in cattle?

alabamensis and auburnensis

what species of Eimeria causes winter coccidiosis and nervous coccidiosis?

Eimeria zuernii

ID

Eimeria (leuckarti)

what is the pathogenic species of Eimeria in camelids?

Eimeria macusaniensis

what is the species of Eimeria in horses that was discussed?

Eimeria leuckarti

how are animals infected with Eimeria?

ingestion of sporulated oocysts

what is the PPP for Eimeria?

about 15 days

what is the main pathology of Eimeria spp?

destruction of intestinal epithelium

what are the two main things that will predispose an animal from being infected with Eimeria?

weak immune system (young animals)

number of oocysts ingested (congestion of herd)

what is the main clinical sign that is caused by Eimeria?

diarrhea

if a cow comes down with diarrhea due to Eimeria zuernii during a cold snap, what condition does this cow have?

winter coccidiosis

what is it called when cattle get neurologic signs from Eimeria?

nervous coccidiosis

what is the treatment of Eimeria in cattle?

Amprolium

what is the treatment for Eimeria in camelids?

nothing FDA approved

ponazuril

what drug class is used to prevent Eimeria infection?

ionophores

is Eimeria zoonotic?

no

how to differentiate Cystoisospera and Eimeria oocysts in dog feces?

morphology

number of sporocysts`

what is the most important species of Cryptosporidium for veterinarians to be aware of?

Cryptosporidium parvum

is Cryptosporidium host specific?

no

how many sporozoites do Cryptosporidium oocysts have?

4

which oocysts appear pale pink on a slide?

Cryptosporidium

ID

Cryptosporidium

how are animals infected with Cryptosporidium?

ingestion of sporulated oocysts

which species get Cryptosporidium most commonly?

humans and cattle

what are the two types of oocysts produced by Cryptosporidia?

thick shelled

thin shelled

what type of oocyst is autoinfective in Cryptosporidia?

thin shelled

how long does it take for Cryptosporidia to be infective after being passed in the feces?

it is immediately infective

what is the PPP of Cryptosporidia?

2-10 days

where do meront and gamont Cryptosporidia develop within the host?

in a parasitophorous vacuole between the cytoplasm and the cell membrane

what age of cattle is Cryptosporidium parvum usually a problem in?

1-4 weeks old

what is the best method of fecal flotations for Cryptosporidium?

Ziehl-Neelsen

what is the treatment for food animals with Cryptosporidium?

nothing

what is the treatment for SA with Cryptosporidium?

Nitazoxanide

what protozoa causes equine protozoal myeloencephalitis?

sarcocystis neurona

what condition does sarcocystis neurona cause?

equine protozoal myeloencephalopathy

what is the DH for sarcocystis neurona?

opossums

what is the IH for Sarcocystis neurona?

skunks, raccoons, armadillos, cats

what kind of host are horses for Sarcocystis neurona?

accidental

how are horses infected with Sarcocystis neurona?

ingestion of sporocysts from possum feces (usually in water)

where does Sarcocystis undergo merogony and sporogony in horses?

the CNS

can EPM be transmitted from one horse to another?

no

what does Sarcocystis neurona form in the IH?

sarcocysts in the muscle

where does Sarcocystis live in the horse?

the CNS

what is the main signs shown with EPM?

asymetric spinal cord signs (muscle atrophy, gait abnormalities, etc.)

what three criteria do you need to fulfill to diagnose EPM?

clinical signs

exclusion of other causes

immunodiagnostic testing

what serum to CSF ratio is necessary to diagnose EPM on a SnSAG ELISA Ab test?

<100

what does a positive serum EPM test indicate?

exposure, but not necessarily infection

what does a negative CSF test for EPM indicate?

EPM is not the cause of disease

what is the treatment for Sarcocystis neurona in horses?

ponazuril

diclazuril

sulfadiazine-pyrimethamine

what organism causes bovine eosinophilic myositis in cattle?

Sarcocystis cruzi

what condition does sarcocystis cruzi cause in cattle?

bovine eosinophilic myositis

what muscles can become infected by bovine eosinophilic myositis?

all striated muscles

is Sarcocystis zoonotic?

humans can become accidental (dead end) hosts for some species

humans also have their own Sarcocystis

what are the major parasites that cause ruminant abortions discussed?

Neospora caninum

Toxoplasma gondii

Tritrichomonas foetus

how is Neospora caninum spread from cow to cow?

transplacentally

what is the infective stage of Neospora caninum in cattle?

ingestion of sporulated oocysts

where do Neospora caninum cysts develop in cattle?

eyes, CNS, and muscle

what is the primary cause of abortion in cattle?

Neospora caninum

what will Neospora caninum cause in a calf if the mother is exposed early gestation vs. late?

early: embryo death

late: weak calf with neurologic signs

what tissue is most damaged in a calf that has contracted Neospora caninum transplacentally?

brain and heart

what are the three clinical patterns that Neospora caninum can have in a herd?

abortion storms

low steady abortion losses

subclinical infections

what are the preferred samples to test for Neospora caninum in cattle?

tissue from the placenta and fetus

serum from the dam

what is the treatment for Neospora caninum?

nothing

is Neospora caninum zoonotic?

no

what role does cattle play for Toxoplasma gondii?

IH

how are cattle infected with Toxoplasma gondii?

ingestion of sporulated oocyst

which stage of Toxoplasma gondii causes the most tissue damage?

tachyzoites

what are the most common species that Toxoplasma gondii causes abortions in?

sheep, goats, humans

what time period of gestation does Toxoplasma gondii usually cause abortions in?

third trimester

what signs could Toxoplasma gondii cause in immunosupressed ewes?

neurologic

how to diagnose Toxoplasma gondii?

antibody testing

what is the antibody test of choice for detecting current infection of Toxoplasma gondii?

IgM

what does the antibody IgG do with Toxoplasma infection?

rises 2-4 weeks after infection and persists for about a year

how to treat sheep and goats for Toxoplasma gondii?

no FDA labeled

EL Ionophores

what is the definitive host of Tritrichomonas foetus?

cattle

where does Tritrichomonas foetus live in cattle?

males: penis and prepuce

females: urogenital tract

how many anterior and posterior flagella does Tritrichomonas foetus have?

3 anterior

1 posterior

what is the nature of Tritrichomonas foetus motion?

jerky and mostly forward

ID parasite

Tritrichomonas foetus

how is Tritrichomonas foetus spread from bull to cow?

breeding or iatrogenic during AI

how long after infection of T. foetus does it take to detect the parasite in the vaginal mucosa?

14-28 days