MPA 324 Menu

Piroplasm Overheads


Taxonomy of Protozoa
Sarcomastigophora
Labrynthomorpha
Apicomplexa
Microspora
Acetospora
Myxozoa
Ciliophora




Taxonomy of Babesia

Phylum - Apicomplexa
Class - Piroplasmea (Sporozoea)
Order - Piroplasmida
Family - Babasidae (Theileriidae & Dactylosomidae)




Family Babessiidae

Intracellular in RBC's
Reproduce by budding (2 rarely 4)
Major veterinary importance
World wide distribution
Babesiosis
Many commensals rather than pathogens
Wild rodents etc
Transmitted by ticks
Family - Ixoxdidae & Argasidae




Morphology
(in mammalian host)

Large & small species
Large - 2-5 um (B. canis)
Small - 1-2um (B. microti)
Normally round or oval
Merozoites
Apical complex - no conoid
Ray bodies
Gametes
Fuse to form motile ookinete




Babesia Life Cycle

Babseia canis




Species of Babasesia
(of veterinary importance)





Diagnosis of Babesia

Clinical picture
Weight loss - lethargy
Haematouria
Fever

Parasitological
Thick & thin bllood smears (Geimsa stained)
Serology
PCR/monoclonal antibodies




Control of Babesia

Tick control
Insecticides

Treatment
Acaprin, berenil, trypan blue
Large species more susceptible

Good husbandry
Vaccination




Immunity to Babesia

Natural infection - life long immunity
Residual - non-clinical infection
Largely T cell mediated
CD4+ & macrophage activation
Antibody - extracellular merozoites




Vaccination

Killed parasites
Attenuated parasites
Passage in splenectomised calves
Recombinant vaccines
Anti-tick vaccines




Theileria





Taxonomy of Theileria

Phylum - Apicomplexa
Class - Piroplasmea (Sporozoea)
Order - Piroplasmida
Family -Theileriidae (Babasidae & Dactylosomidae)




Family Theileriidae

Intracellular in RBC's & lymphocytes
Reproduce asexually - Macro & micro schizonts
Reproduce sexually - invertebrate
Major veterinary importance
Largely tropics & sub tropics
East Coast Fever
Mediterranean Coast Fever
Transmitted by ticks
Family - Ixoxdidae




Morphology
(in mammalian host)

Macroschizont
Irregular shape - often ovoid
10-20um in diameter
Multinucleate - extracellular
Induce lymphocyte division
Up to 80% of lymphocytes parasitised

Microschizont
Increased parasite nuclear division
Uninucleate merozoites
Source of RBC infection - gametocytes




Life Cycle of Theileria





Species of Theileria
(of veterinary importance)





Diagnosis of Theileriosis

Clinical features
Weight loss
Enlarged lymph nodes & spleen
Mild anemia
Haematouria (rare)

Parasitological
Lymph node biopsy - smear
Thick & thin blood films




Pathogenesis of Theileria

Incubation period
9-24 days - tick density dependent
Draining lymph node enlargement
General hypertrophy
Spleen & liver
Lymphopoesis
Fever CNS - turning sickness
Pulmonary involvement
Immunologically mediated




Control of Theilerosis

Tick control
Insecticides

Treatment
Butalex, menoctone, tetracyclins
Prophylatic in calves
Infection & cure




Vaccination

Live sporozoite
Attenuated macroschizont
Sporozoite - recombinant

____________________________Click to Return To Top of Page____________________________


E-mail any comments or suggestions to: D.P. Humber@UEL.AC.UK
©David Humber 1996 - Last Modified: Tuesday, February 27, 1996 at 09:15 PM
Humber's Home Page | David's Parasite Paradise | Table of Contents |