Lecture 30 - Coccidia [Eimeria] 2

Question 1

describe eimeria morphology when infective

Answer 1

sporulated oocyst with 2 sporozoites in each 4 sporocysts

Question 2

T/F: oocysts of eimeria are species-specific

Answer 2

TRUE

Question 3

describe the life cycle of eimeria in 4 steps

Answer 3

1. unsporulated cysts pass in feces
2. sporulation in 2-3 days
3. ingestion of sporulated oocyst
4. disease

Question 4

where does sporogony occur for eimeria

Answer 4

in the environment (due to temp, moisture, and oxygen)

Question 5

what is the pathogenesis of eimeria

Answer 5

direct destruction of enterocytes with each merogonic cycle

Question 6

what 4 things does the destruction of epithelial lining cause

Answer 6

1. hemorrhagic ulcers = produce blood
2. decreased absorption = malabsorption
3. traumatic permeability = loss of fluids and blood into gut lume
4. inflammation causes increased permeability and secretion

Question 7

what is the clinical disease caused by eimeria

Answer 7

mild to severe bloody, mucoid or watery diarrhea in young animals

Question 8

coccidia (e.g. eimeria) occurs at what age

Answer 8

21+ days

Question 9

T/F: coccidiosis clinical disease is primarily a herd disease

Answer 9

TRUE

Question 10

give the presentation for a herd/flock eimeria infection

Answer 10

regularly recurring diarrhea issues with each successive cohort of young animals

Question 11

give the presentation for an individual eimeria infection

Answer 11

non-clinical but larger numbers of oocysts in feces
or
acute, severe, fatal diarrhea

Question 12

disease is caused by what 2 factors regarding eimeria

Answer 12

1. overwhelming dose of oocysts
2. moderate dose of oocysts and stress

Question 13

what diagnostics are available for eimeria

Answer 13

1. fecal float centrifugation (multiple of several days)
2. ID species

Question 14

what is most important in eimeria treatment

Answer 14

supportive fluid therapy

Question 15

what is the treatment for eimeria

Answer 15

• ionophores (-cidal) and sulfonamides (-stat)
• isolate animals
• supportive fluid therapy
• treat prophylactically (feed or water additives)

Question 16

what is the control protocol for eimeria

Answer 16

1. dry environment
2. separate age groups
3. prevent fecal contamination
4. reduce stress
5. prophylactic

Question 17

what is the goal of anticoccidial use

Answer 17

limit infections in newly exposed host to allow to develop, without clinical disease

Question 18

what anticoccidials are highly toxic to horses

Answer 18

ionophores

Question 19

T/F: vaccination for eimeria is not common to the poultry industry

Answer 19

FALSE

Question 20

what are the host risk factors for eimeria

Answer 20

1. immunodeficient = young, stressed, poor nutrition
2. immunologically naive = young, new import

Question 21

incomplete protection against eimeria results in

Answer 21

reinfection asymptomatic shedding of oocyst

Question 22

what are the environmental risk factors of eimeria

Answer 22

1. moist, warm to cool (spring/fall)
2. crowded conditions

Question 23

Bovine coccidiosis

Answer 23

E. bovis, E. zuernii

chronic: unthrifty, some scours w/ watery diarrhea +/- blood

severe: thin, blood D+, fever, anorexia, depression, dehydration, weight loss

Question 24

T/F: once oocysts appear in feces of bovine, it is too late to stop infection

Answer 24

TRUE

Question 25

sheep and goat coccidiosis

Answer 25

Sheep = E. ovinoidalis Goats = E. arloingi, E. ninakoh D+, dehydration, secondary concerns

Question 26

sheep coccidiosis is associated with ____ and goats tend to be more ____

Answer 26

stress; susceptible

Question 27

what are secondary concerns in sheep and goat coccidiosis

Answer 27

1. fly strike 2. bacterial enteritis

Question 28

what age group of goats/sheep are most susceptible to coccidiosis

Answer 28

1-6 months

Question 29

T/F: Swine & Horse coccidiosis have high pathogenicity

Answer 29

FALSE

Question 30

swine coccidiosis

Answer 30

8 eimeria spp.

Question 31

horse coccidiosis

Answer 31

E. leuckarti (non-pathogenic)

Question 32

poultry coccidiosis

Answer 32

massive destruction of epithelial cells particularly in young birds

Question 33

T/F: poultry coccidiosis can be self-limiting or have high mortality

Answer 33

TRUE

Question 34

Is there economic loss associated with poultry coccidiosis

Answer 34

yes - poor weight, reduced production

Question 35

chicks <4 wk/o will be affected by _____ and those >6 wk/o are affected by _____

Answer 35

E. tenella; E. necatrix

Question 36

what are the clinical signs of poultry coccidiosis

Answer 36

1. bloody feces 2. pale combs 3. ruffled feathers 4. coagulated blood in ceca

Question 37

T/F: different eimeria spp. infect different regions of gastrointestinal tract

Answer 37

TRUE

Question 38

how is coccidiosis managed on farms

Answer 38

- raised floor, water, and food - sanitation - thin liter - keep age groups separate

Question 39

T/F: if one chicken is sick from suspected eimeria the whole flock should be treated

Answer 39

TRUE

Question 40

how is poultry coccidiosis diagnosed

Answer 40

1. speciate by location of intestinal lesions 2. GI mucosa smear to identify schizonts 3. fecal float 4. PCR