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**This family has both an erythrocytic and a tissue (leukocytic) phase
**This family has both an erythrocytic and a tissue (leukocytic) phase
*The ''Babesiidae'', a related family, is characterized by having a primarily erythrocytic phase in the mammalian host
**Its morphological features are indistinguishable from the erythrocytic form of Cytauxzoon
*The ''Babesiidae'', a related family, is characterized by having a primarily erythrocytic phase in the mammalian host **Its morphological features are indistinguishable from the erythrocytic form of Cytauxzoon
*''Cytauxzoon felis'', ''B. equi'', and ''B. rodhaini'' have been linked to both the babesias and theilerias by RNA gene sequence analysis
*''Cytauxzoon felis'', ''B. equi'', and ''B. rodhaini'' have been linked to both the babesias and theilerias by RNA gene sequence analysis
**It has been suggested that these organisms be reclassified within a separate family
**It has been suggested that these organisms be reclassified within a separate family
*In the life cycle of ''C. felis'', schizonts develop within mononuclear phagocytes, initially as indistinct vesicular structures and later as large, distinct nucleated schizonts that actively undergo division by true schizogony and binary fission
'''Life Cycle'''
*Large schizonts of ''C. felis'' develop in [[Macrophages - WikiBlood|macrophages]]
**In Theileria the exoerythrocytic stage occurs primarily within [[Lymphocytes - WikiBlood|lymphocytes]]
*In ''C. felis'', schizonts develop within mononuclear phagocytes, initially as indistinct vesicular structures and later as large, distinct nucleated schizonts that actively undergo division by true schizogony and binary fission
*Later in the course of the disease, schizonts develop buds (merozoites) that separate and eventually fill the entire host cell
*Later in the course of the disease, schizonts develop buds (merozoites) that separate and eventually fill the entire host cell
*Each schizont may contain numerous merozoites
**Ultrastructurally, schizonts lack a parasitophorous vacuole, and individual merozoites possess rhoptries
*The host cell ruptures, releasing merozoites into the tissue fluid and blood
*The host cell ruptures, releasing merozoites into the tissue fluid and blood
*Merozoites appear in [[Macrophages - WikiBlood|macrophages]] one to three days before they are observed in [[Erythrocytes - WikiBlood|erythrocytes]]
*Merozoites appear in [[Macrophages - WikiBlood|macrophages]] one to three days before they are observed in [[Erythrocytes - WikiBlood|erythrocytes]]
'''Pathogenicity'''
*[[Suborder: Metastigmata, ticks|Ticks]] are implicated as the natural vector for ''Cytauxzoon''
**Most cases of infection have been associated with the presence of these parasites on the hosts
**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, dyspnea, anorexia, lymphadenopathy, anaemia, and icterus leading to death in three to six days
**Minimal inflammatory reaction is present in tissues
**Minimal inflammatory reaction is present in tissues
'''Diagnosis'''
*Merozoites within [[Erythrocytes - WikiBlood|erythrocytes]], best seen on peripheral blood or tissue impressions, are variable in morphology and can occur as round, oval, or signet ring-shaped bodies
*Merozoites within [[Erythrocytes - WikiBlood|erythrocytes]], best seen on peripheral blood or tissue impressions, are variable in morphology and can occur as round, oval, or signet ring-shaped bodies
**Are 1-5 micrometers in diameter
**Are 1-5 micrometers in diameter