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==Introduction==
==Introduction==
The '''piroplasms''' are a group of blood-bourne protozoa which are transmitted by [[Suborder: Metastigmata, ticks|ticks]]. The two species most of veterinary importance are ''Babesia'', ''Cytauxzoon'' and ''Theileria''.
The '''piroplasms''' are a group of blood-borne protozoa which are transmitted by [[Suborder: Metastigmata, ticks|ticks]]. The species of most veterinary importance are ''Babesia'', ''Cytauxzoon'' and ''Theileria''.
Piroplasms are apicomplexan protozoa which inhabit [[Erythrocytes - WikiBlood|erythrocytes]], and sometimes other cells of vertebrates, but do not form pigment from haemoglobin. All piroplasms are small and round or pear-shaped (erythrocyte forms) and are parasitic on fish, amphibians, birds and mammals.
Piroplasms are apicomplexan protozoa which inhabit [[Erythrocytes - WikiBlood|erythrocytes]], and sometimes other cells of vertebrates, but do not form pigment from haemoglobin. All piroplasms are small and round or pear-shaped (erythrocyte forms) and are parasitic to fish, amphibians, birds and mammals.
==''Babesia''==
==''Babesia''==
'''Life Cycle'''
'''Life Cycle'''
*Both [[Suborder: Metastigmata, ticks#Disease Transmission|trans-stadial]] and [[Suborder: Metastigmata, ticks#Disease Transmission|trans-ovarian]] occurs
*Both [[Suborder: Metastigmata, ticks#Disease Transmission|trans-stadial]] and [[Suborder: Metastigmata, ticks#Disease Transmission|trans-ovarian]] transmission occurs
*Each female [[Suborder: Metastigmata, ticks|tick]] produces 3000 eggs
*Each female [[Suborder: Metastigmata, ticks|tick]] produces 3000 eggs
*''Babesia'' multiplies in the red blood cells by '''budding'''
*''Babesia'' multiplies in the red blood cells by '''budding'''
**Forms 2-4 daughter cells (species dependent)
**Forms 2-4 daughter cells (species dependent)
**Giemsa blood smears can differentiate between species using 'Diffquik' stain
**Giemsa blood smears can differentiate between species using 'Difquik' stain
*''Babesia'' species are either small or large depending on the size of the daughter cells
*''Babesia'' species are either small or large depending on the size of the daughter cells
**Spread and infect other red blood cells
**Spread and infect other red blood cells
*Antigen is released which absorbs onto other red blood cells
*Antigen is released which adsorbs onto other red blood cells
**Causes haemolysis and [[General Pathology - Pigmentation and Calcification#Haemoglobin|haemoglobin pigmentation]]
**Causes haemolysis and [[General Pathology - Pigmentation and Calcification#Haemoglobin|haemoglobin pigmentation]]
**Causes haemolytic anaemia, haemoglobinuria and fever
**Causes haemolytic anaemia, haemoglobinuria and fever
'''Epidemiology'''
'''Epidemiology'''
*Determined by:
*Determined by:
**Number of infected [[Suborder: Metastigmata, ticks|ticks]] seeking a blood mean ('''tick pressure''')
**Number of infected [[Suborder: Metastigmata, ticks|ticks]] seeking a blood meal ('''tick pressure''')
**Calves under 9 months are refractory to disease
**Calves under 9 months are refractory to disease
***Can develop immunity if exposed without showing clinical signs
***Can develop immunity if exposed without showing clinical signs
**Premunity developes quickly in infected cattle which causes a 'carrier state'
**'Premunity' (a good protective immunity) develops quickly in infected cattle causing a 'carrier state'
**Immunity can wane in the absense of re-infection
**Immunity can wane in the absence of re-infection
**Uninfected cattle remain susceptible
**Uninfected cattle remain susceptible
*Predisposing factors:
*Predisposing factors:
**Sucseptible animals introduced into an infected area
**Susceptible animals introduced into an infected area
**Infected [[Suborder: Metastigmata, ticks|ticks]] are intorduced into a clean area
**Infected [[Suborder: Metastigmata, ticks|ticks]] introduced into a clean area
**Infected cattle are introduced into an area with clean [[Suborder: Metastigmata, ticks|ticks]]
**Infected cattle introduced into an area with clean [[Suborder: Metastigmata, ticks|ticks]]
**Temporary reduction in the [[Suborder: Metastigmata, ticks|tick]] population decreasing the transmission rate (causing enzootic instability)
**Temporary reduction in the [[Suborder: Metastigmata, ticks|tick]] population decreasing the transmission rate (causing enzootic instability)
**Infected are transported or stressed in other ways, e.g. parturition
**Infected are transported or stressed in other ways, e.g. parturition
*Overseas
*Overseas
**''B. bovis'' causes considerable losses in cattle throughout many tropical and sub-tropical areas
**''B. bovis'' causes considerable losses in cattle in many tropical and sub-tropical areas
***In Australia an attenuated vaccine is used
***In Australia an attenuated vaccine is used
***Vector is [[Suborder: Metastigmata, ticks#Important Hard Ticks|''Boophilus'']]
***Vector is [[Suborder: Metastigmata, ticks#Important Hard Ticks|''Boophilus'']]
*Dogs
*Dogs
**Complex epidemiology
**Complex epidemiology
**Recognised species are extending their endemic ranges due to the disovery of the small ''Babesia'' species, pet passport scheme and increased overseas travel
**Recognised species are extending their endemic ranges due to the discovery of the small ''Babesia'' species, pet passport scheme and increased overseas travel
**Large species comprises 3 subspecies
**Large species comprises 3 subspecies
***''B. canie canis'' is the msot important
***''B. canis canis'' is the most important
****[[Suborder: Metastigmata, ticks#Important Hard Ticks|''Dermacentor'']] vector
****[[Suborder: Metastigmata, ticks#Important Hard Ticks|''Dermacentor'']] vector
****Largely confined to southern Europe but is spreading
****Largely confined to southern Europe but is spreading
***''B. canis'' uses [[Suborder: Metastigmata, ticks#Important Hard Ticks|''Rhipicephalus'']] as a vector and is spreading northwards through Europe
***''B. canis'' uses [[Suborder: Metastigmata, ticks#Important Hard Ticks|''Rhipicephalus'']] as a vector and is spreading northwards through Europe
***''B. gibsoni'' is now established in the USA and South-East Asia
***''B. gibsoni'' is now established in the USA and South-East Asia
**British dogs have no immunity as no species are endemic to the UK so are highly suceptible if taken abroad
**British dogs have no immunity as no species are endemic to the UK so are highly susceptible if taken abroad
**Prevent [[Suborder: Metastigmata, ticks|tick]] bites by a 'Amitraz' collar is currently the best method of protection
**Prevention of [[Suborder: Metastigmata, ticks|tick]] bites by use of an 'Amitraz' collar is currently the best method of protection
*Horses
*Horses
*Sheep and goats
*Sheep and goats
**Several species
**Several species
**Little clincial significance
**Little clinical significance
===Enzootic Instability===
===Enzootic Instability===
**Experimentally, ''Dermacentor variabilis'' can transmit the organism from bobcats to domestic cats. In a white tiger that developed a natural, fatal infection in Florida, two female Lone Star ticks (''Amblyomma americanum'') were present on the inguinal skin.
**Experimentally, ''Dermacentor variabilis'' can transmit the organism from bobcats to domestic cats. In a white tiger that developed a natural, fatal infection in Florida, two female Lone Star ticks (''Amblyomma americanum'') were present on the inguinal skin.
*Clinically, the disease in cats is characterized by fever, depression, dyspnea, anorexia, lymphadenopathy, anaemia, and icterus leading to death in three to six days
*Clinically, the disease in cats is characterized by fever, depression, dyspnoea, anorexia, lymphadenopathy, anaemia and icterus leading to death in three to six days
*Gross findings include pale or icteric mucous membranes, petechiae and ecchymoses in the [[Lungs - Anatomy & Physiology|lung]], [[Heart - Anatomy & Physiology|heart]], [[Lymph Nodes - Anatomy & Physiology|lymph nodes]] and on mucous membranes, splenomegaly, lymphadenomegaly, and hydropericardium
*Gross findings include pale or icteric mucous membranes, petechiae and ecchymoses in the [[Lungs - Anatomy & Physiology|lung]], [[Heart - Anatomy & Physiology|heart]], [[Lymph Nodes - Anatomy & Physiology|lymph nodes]] and on mucous membranes, splenomegaly, lymphadenomegaly, and hydropericardium
*Microscopically, numerous large schizonts are present within the cytoplasm of endothelial-associated [[Macrophages - WikiBlood|macrophages]]
*Microscopically, numerous large schizonts are present within the cytoplasm of endothelial-associated [[Macrophages - WikiBlood|macrophages]]
**Infected macrophages become markedly enlarged (up to 75μm) and may occlude the lumens of numerous vessels of many tissues, especially the [[Lungs - Anatomy & Physiology|lungs]]
**Infected macrophages become markedly enlarged (up to 75μm) and may occlude the lumen of numerous vessels of many tissues, in particular the [[Lungs - Anatomy & Physiology|lungs]]
**Minimal inflammatory reaction is present in tissues
**Minimal inflammatory reaction is present in tissues
***[[Suborder: Metastigmata, ticks#Disease Transmission|Trans-stadial]] transmission
***[[Suborder: Metastigmata, ticks#Disease Transmission|Trans-stadial]] transmission
*Other ''Theileria'' species causes production losses in cattle and sheep in the Middle East, Mediterranean and in Northern Africa
*Other ''Theileria'' species cause production losses in cattle and sheep in the Middle East, Mediterranean and in Northern Africa
'''Life Cycle'''
'''Life Cycle'''
*Examine Giemsa stained smears of:
*Examine Giemsa stained smears of:
**Local [[Lymph Nodes - Anatomy & Physiology|lymph node]] aspirated for schizonts
**Local [[Lymph Nodes - Anatomy & Physiology|lymph node]] aspirated for schizonts
**Blood smears for pioplasms in red blood cells
**Blood smears for piroplasms in red blood cells
*Post-mortem
*Post-mortem
**Pulmonary oedema
**Pulmonary oedema
**Gut mucosal haemorrhages
**Gut mucosal haemorrhages
**[[Lymph Nodes - Anatomy & Physiology|Lymph node]] and [[Spleen - Anatomy & Physiology|spleen]] cellular atrophy
**[[Lymph Nodes - Anatomy & Physiology|Lymph node]] and [[Spleen - Anatomy & Physiology|splenic]] cellular atrophy
'''Control'''
'''Control'''
*Integrated control of both the [[Suborder: Metastigmata, ticks|tick]] and vector
*Integrated control of both the [[Suborder: Metastigmata, ticks|tick vector]] and disease
**[[Vaccines - WikiBlood|Vaccination]] and [[ectoparasiticides]]
**[[Vaccines - WikiBlood|Vaccination]] and [[ectoparasiticides]]