Lecture 30 - Coccidia [Eimeria] 2 Flashcards
describe eimeria morphology when infective
sporulated oocyst with 2 sporozoites in each 4 sporocysts
T/F: oocysts of eimeria are species-specific
TRUE
describe the life cycle of eimeria in 4 steps
- unsporulated cysts pass in feces
- sporulation in 2-3 days
- ingestion of sporulated oocyst
- disease
where does sporogony occur for eimeria
in the environment (due to temp, moisture, and oxygen)
what is the pathogenesis of eimeria
direct destruction of enterocytes with each merogonic cycle
what 4 things does the destruction of epithelial lining cause
- hemorrhagic ulcers = produce blood
- decreased absorption = malabsorption
- traumatic permeability = loss of fluids and blood into gut lume
- inflammation causes increased permeability and secretion
what is the clinical disease caused by eimeria
mild to severe bloody, mucoid or watery diarrhea in young animals
coccidia (e.g. eimeria) occurs at what age
21+ days
T/F: coccidiosis clinical disease is primarily a herd disease
TRUE
give the presentation for a herd/flock eimeria infection
regularly recurring diarrhea issues with each successive cohort of young animals
give the presentation for an individual eimeria infection
non-clinical but larger numbers of oocysts in feces
or
acute, severe, fatal diarrhea
disease is caused by what 2 factors regarding eimeria
- overwhelming dose of oocysts
- moderate dose of oocysts and stress
what diagnostics are available for eimeria
- fecal float centrifugation (multiple of several days)
- ID species
what is most important in eimeria treatment
supportive fluid therapy
what is the treatment for eimeria
- ionophores (-cidal) and sulfonamides (-stat)
- isolate animals
- supportive fluid therapy
- treat prophylactically (feed or water additives)
what is the control protocol for eimeria
- dry environment
- separate age groups
- prevent fecal contamination
- reduce stress
- prophylactic
what is the goal of anticoccidial use
limit infections in newly exposed host to allow to develop, without clinical disease
what anticoccidials are highly toxic to horses
ionophores
T/F: vaccination for eimeria is not common to the poultry industry
FALSE
what are the host risk factors for eimeria
- immunodeficient = young, stressed, poor nutrition
- immunologically naive = young, new import
incomplete protection against eimeria results in
reinfection asymptomatic shedding of oocyst
what are the environmental risk factors of eimeria
- moist, warm to cool (spring/fall)
- crowded conditions
Bovine coccidiosis
E. bovis, E. zuernii
chronic: unthrifty, some scours w/ watery diarrhea +/- blood
severe: thin, blood D+, fever, anorexia, depression, dehydration, weight loss
T/F: once oocysts appear in feces of bovine, it is too late to stop infection
TRUE
sheep and goat coccidiosis
Sheep = E. ovinoidalis
Goats = E. arloingi, E. ninakoh
D+, dehydration, secondary concerns
sheep coccidiosis is associated with ____ and goats tend to be more ____
stress; susceptible
what are secondary concerns in sheep and goat coccidiosis
- fly strike
- bacterial enteritis
what age group of goats/sheep are most susceptible to coccidiosis
1-6 months
T/F: Swine & Horse coccidiosis have high pathogenicity
FALSE
swine coccidiosis
8 eimeria spp.
horse coccidiosis
E. leuckarti (non-pathogenic)
poultry coccidiosis
massive destruction of epithelial cells particularly in young birds
T/F: poultry coccidiosis can be self-limiting or have high mortality
TRUE
Is there economic loss associated with poultry coccidiosis
yes - poor weight, reduced production
chicks <4 wk/o will be affected by _____ and those >6 wk/o are affected by _____
E. tenella; E. necatrix
what are the clinical signs of poultry coccidiosis
- bloody feces
- pale combs
- ruffled feathers
- coagulated blood in ceca
T/F: different eimeria spp. infect different regions of gastrointestinal tract
TRUE
how is coccidiosis managed on farms
- raised floor, water, and food
- sanitation
- thin liter
- keep age groups separate
T/F: if one chicken is sick from suspected eimeria the whole flock should be treated
TRUE
how is poultry coccidiosis diagnosed
- speciate by location of intestinal lesions
- GI mucosa smear to identify schizonts
- fecal float
- PCR
