Coccidia Flashcards
What kinds of Coccidia have these lifecycles?
Top = Eimeria, Cryptosporidium
Middle = Isospora, Toxoplasma
Bottom = Sarcocystis
What coccidia is this the lifecycle of?
Eimeria.
- Sporulation = From non-sporulated oocyst to sporulated oocyst.
- Excystation = Sporocyst from oocyst, and sporozoite from sporocyst.
- Asexual Repro - Schizogony
- Sexual Repro - Gametogony
What is species this the Oocyst of?
Eimeria species.
The sporulated oocyst has 4 sporocysts, each containg two sporozoites.
Which group of avian eimeria show this type of pathogenicity? Give examples from the group.
Malabsorption Eimeria -
villous atrophy and mucoid enteritis ->decreased
weight gain & increased feed conversion ratio
e.g. E. acervulina, E. maxima
Which group of avian Eimeria cause this type of pathogenicity? What is the clinical signs of this? Give examples of the species.
Haemorrhagic Eimeria -
Cells rupture to release merozoites causing deep
erosions and haemorrhage -> bloody faeces, high
morbidity, mortality
e.g. E. tenella, E. necatrix, E. brunetti
These are two poultry Eimeria species. They have different sized oocysts, give an example of the species that may have these different sized oocysts.
Big = E. Maxima
Small = E. mitis
When lesion scoring for poultry Eimeria species, what are the four ‘groups’ the GIT can be split into? How is it scored?
Pink = Upper Intenstine “U”
Dark Grey = Middle Intestine “M”
Orange = Lower Small Intestine and Rectum “L”
Light grey = Caeca
Scored from 0 (no lesions) to +4 (extreme severe)
What group of Eimeria species would cause a bird to have this kind of faeces?
Haemorrhagic species
What is this showing in a cow? What kind of coccidiosis can cause this?
Haemorrhagic typhlocolitis = diarrhoea with pieces of muscosa
It is cause by stable coccidiosis (caused by E. bovis and E. zuernii)
What kind of Eimeria cause pasture coccidiosis in cattle? What is the clinical signs?
E. alabamensis
It is associated with mucoid enteritis, and is apparent shortly after turnout.
What Eimeria species is this the lifecycle of?
E. bovis
What two eimeria species infect sheep? What is their major clinical sign? How can you spot this? (see picture)
E. ovinodalis and E. crandalis
Both are characterised by typhlocolitis, and the macromeront formation = large white spots
Primarily a disease of the young, PPP = 2 weeks
The left is a Strongyle egg, the one on the right is an Eimeria species. Which Eimeria species, and which species does it belong to?
E. leukarti, which infects horses.
Which coccidia is confined this the lifecycle of? ( Clue: where it infects in the villi)
Cryptosporidium - it only infects the brush border of cells.
What protozoa has trophozoites that characteristically look like this (pear shaped, sticky adhesion disc)? What is the significance of this?
Giardia.
Trophozoites attach to intestinal wall and reproduce by binary fission. Commonest cause of protozoal diarrhoea in Humans in UK
What protozoa has this characteristic shape? What hosts does it infect, why is it important?
Histomonas meleagridis - causes blackhead in Turkey’s
Round/Oval, One Flagellum
Explain the lifecycle of Histomonas meleagridis and it’s interaction with Heterakis
What protozoa is this the characteristic shape of?
Balantidium - ciliate protozoa, funnel shaped cytosome, macro and micronucleus, contractile and food vacuoules
It can cause ulceration and dysentary
