Dogs and cats protozoa Flashcards
C/s of giardia in pets
Subclinical very common
Prevelance of giardia in pets
Dogs 7-40%, cats 8-10%
Risk factors for giradia
Young animals (<1 year)
Suboptimal environment
stressed/immunocompromised
Reinfection very common
Life cycle of giardia
Cysts in enviro can survive for months and are immediately infective
Feces have a few tz, millions of cysts
Minimum infective dose as low as 10 cysts
Shedding is intermittent
May last for months
Host has trophozoites, attach to enterocytes, divide by binary fission
Clinical signs of giardiasis
Most often asymptomatic
Diarrhea +/- mucous or fat, rarely blood
May be acute, chronic or recurring
Flatulence, vomiting (occasionally), nausea
Abdominal pain
Lethargy, decreased appetite, weight loss
Food allergies: dermatitis due to increased permeability of GIT wall to food antigens
Diagnosis of giardia
Only test diarrheic animals or high risk households
Multiple fecal samples (can be intermittent shedding of cysts)
3 samples over 2-3 day intervals
Diagnostic test options
Direct, fresh fecal smear (trophozoites, cysts)
Zinc sulfate floatation (cysts)
ELISA SNAP test (cyst antigen)- test of choice in clinic
Immunofluorescent assay (IFA)(cyst antigen)- test of choice to order from diagnostic lab
Control of giardia
Only treat if diarrheic animals or high risk households
Goals of Tx: decrease clinical signs and environmental contamination
Not elimination of infection
Re-testing is not likely to be helpful
Inform clinics of zoonotic risk (both ways!)
Sanitation- clean environment and bathe dog
Heat, dry, bleach or other disinfectants
Metronidazole, fenbendazole, ronidazole (off label use)
Protozoa of cats
Mucosoflagellates
Tritrichomonas blagburni (foetus) (Cat strain)
Characteristics of Tritrichomonas blagburni
Shed and infective stage
Not environmentally resistant
No cysts
Pathogenesis, diagnosis and control of Tritrichomonas blagburni
Cats <1 year old, catteries, carriers
Chronic, large bowel diarrhea
Diagnosis
Fecal smear (saline)
Culture and microscopy (InPouchTM TF-feline)
PCR
No labelled treatment
Ronidazole, metronidazole
Dog and cats protozoa
Apicomplexans
-Coccidia (gastrointestinal- one host)
Cystoisopora, Cryptosporidium
-Coccidia (tissue cyst - 2 or more hosts)
Toxoplasma, neospora, sarcocytis
Highly host specific, and even GIT location specific NOT zoonotic
Coccidia of dogs
Cystoisospora canis
Cystoisospora ohioensis
Cystoisospora burrowsi
Coccidia of cats
Cystoisospora felis
Cystoisospora rivolta
Cystoisospora spp, life cycle
Asexual reproduction (2 or more rounds)(merogony)
Sexual reproduction(gemetogony)
Sporulated cysts in poop
Cat can ingest the cysts or a PH can
Pathogenesis of coccidiosis
Pups and kittens (breeders and shelters)
Often asymptomatic
Stress (weaning, concomitant disease)
Heavily contaminated environment
Destroy epitliial cells in prepatent period
Diarrhea, dehydration, poor growth
Watery, sometimes bloody, diarrhea (even in PPP)
Diagnosis of coccidiosis
Diagnosis
Clinical appearance
Fecal flotation: numbers of oocytes significant
Diagnosis and control of coccidiosis
Supportive (hydration)
Environmental decontamination
Goal of tx: reduce shedding ( deceased clinical signs?)
Sulfonamides, furazolidone (coccidiostatic)
Toltrazuril, ponazuril (coccidiocidal)
High risk shelters/kennels: treat dogs at weeks 3,5,7
Apicomplexans can cause
Tissue cysts (2 or more IHs, 1 DH)
Toxoplasma gondii
Filed only definitive hosts
Wide range of vertebrates serve as intermediate hosts (including cats, dogs, and people)
Toxoplasma sporulated oocysts are produced when
Oocytes produced for only a few weeks once in cats lifetime; can be 100s of millions/cat; survive in moist soil for 1 year, water 5 years
Pathogenesis of toxoplasmosis
In any cat- first time infection is the only time infected
Self limiting diarrhea, fever, oocysts in feces
Transplacental transmission to litter of queen infected for first time in pregnancy
Most severe in congenitally infected kittens
Anorexia, lethargy, diarrhea, pneumonia, icterus, encephalitis, ocular lesions (uveitis)
In IH, often asymptomatic; can transmit through carnivry and vertically
A few hosts when acutely infected in pregnancy may abort
Diagnosis of toxoplasmosis
Fecal flotation (oocysts only shed for 2 weeks)
Serology, immunohistochemistry, PCR
control of toxoplasmosis
Clean litter boxes daily (before sporulation)
Keep cats indoors (out of gardens, away from prey)
Feed only commercial, cooked or frozen diets
Goal of treatment is primarily to reduce transmission (congenital or oocyst shedding)
Clindamycin, pyrimethamine, trimethoprim sulphas
Freeze at -18*C for at least 3 days
Mitigation of T.gondii for pregnant owners
Blanket recommendations
Avoid cleaning the litter box
Gardening
Consumption of undercooked egg
Raw milk
Unwashed produce and unfiltered water
<1% of cats shedding at any given time: young, outdoor
For highly concerned owner: serology followed by 4 fecal exams at weekly intervals
Keep cat indoors, feed only commercial diet or cooked or frozen diets
Neospora caninum is
Neospora caninum
DH: dogs and wild canids
IH: cattle, wild ungulates other carnivores including cats
Not zoonotic
IH not infected through carnivory
Life cycle of Neospora caninum
Eggs in feces of DH sporulates in 1-3 d patency 3 weeks
Ingested by IH
Tissue cysts or placenta abortus is eaten by DH
Pathogenesis of Neospora
Oten asymptomatic
Not all pups infected with tissue cysts and not all infected show signs
Can infect subsequent litters
Most severe in congenitally infected puppies: neurological and skeletal muscle (progressive hindlimb paralysis, dysphagia)
Older dogs: encephalitis, myopathy, ulcerative dermatitis
Diagnosis Neospora in dogs
Clinical appearance
Serology (serum, CSF): IFAT, ELISA
histology/cytology and IHC; PCR
control of Neospora in dogs
Do not allow dogs to eat placenta, fetus or dead calves
Do not breed seropositive female dogs
Sulphonamides, clindamycin
Sacocytis sp life cycle
Sporocysts with 4 sporozoites in feces
Immedialty infective
Devleop in IH for >2 months (merogony)
Sarcocysts with bradyzoites in tissue
Eaten by DH
now have Gemtrogony and progony
Sarcocystis- pet perspective
Pathogenesis: none as DH
Diagnosis
Fecal flotation
Control
Do not feed raw meat and organs
