10 Ruminant Protozoa

Why are Eimeria spp. (coccidia) not zoonotic

Eimeria spp. are incredibly host, site, and cell specific

T/F: Eimeria spp. are likely to cause coccidiosis

F; many species are non or mildly pathogenic

CS associated with coccidiosis

Severe diarrhea ± blood, dehydration

Patient demographic for coccidiosis

Young, old, and stressed

Ruminant species that is more likely to die from coccidiosis

Goats

Why is “winter coccidiosis” a thing

Animals in closer contact to preserve warmth spread disease more easily

Coccidiosis syndrome more common in the NW US

“Nervous coccidiosis” causing neuro signs and occasionally death

Type of life cycle in Eimeria spp.

Direct LC

Where does Eimeria spp. set up shop

Various locations in the SI

Gross lesions associated with the more pathogenic species of Eimeria spp.

Nodules in the SI

How do DH get infected with Eimeria spp.

Ingestion of sporulated oocysts

How long does it take for an oocyst to undergo sporogony

24-48 hours in environment

How does Eimeria spp. (and any apicomplexan really) cause damage in the host

Asexual replication (schizogony/merogony) is incredibly damaging

Morphology of Eimeria spp. eggs

Small but variable egg with centrally located morula or spores (depending on development), may see a micropyle cap if you are lucky

Eimeria spp. that are different than normal and are larger and brown

Eimeria macusaniensis (camelids)

Goal of Eimeria spp. treatment

Manage clinical disease

Management techniques to decrease incidence of coccidiosis

• Reduce exposure to infective oocysts: clean feces, elevate feed

• Prophylactic treatment

When should prophylactic coccidiostats be given

Just before or just after a period of increased stress

How do prophylactic coccidiostats allow for adaptive immunity

Knocks down the level of internal Eimeria spp. but doesn’t wipe out the entire population

Eimeria spp. treatment that is toxic to horses

Ionophores

Coccidiostats used in goats

Decoquinate, monensin

ELDU that may be warranted but cannot be used for market animals

Diclazuril or toltrazuril

CRYPTOSPORIDIUM