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The distribution of anaplasmosis is increasing all the time.
 
The distribution of anaplasmosis is increasing all the time.
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==Lifecycle and Transmission==
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==Transmission==
 
[[File:Theileria_lifecycle.gif|thumb|200px|right|Theileria Lifecycle]]
 
[[File:Theileria_lifecycle.gif|thumb|200px|right|Theileria Lifecycle]]
[[Theileria]] species replicate '''asexually''' in the host [[Primary Lymphoid Tissue | primary]] and [[Secondary Lymphoid Tissue | secondary]] '''lymphoid''' tissues, forming '''schizonts'''.
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These then develop into '''piroplasma''' within the [[Erythrocytes | erythrocytes]].  
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[[Theileria]] species first invade the local [[Lymph Nodes - Anatomy & Physiology|lymph nodes]] of the hosts before disseminating through the lymphoid tissues. Asexual reproduction in the host is followed by sexual reproduction within the [[Ticks | tick]] vector. The [parasite is then transmitted through the salivary glands of the tick into the mammalian host during bloodfeeding.
These piroplasms include the gametes which are infective for ticks and capable of '''sexual reproduction'''.
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Transmission is then '''trans-stadial'''.
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For more information on ticks as vectors, see [[Theileria]] and [[Tick Disease Transmission]]
 
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Sexual reproduction of the parasite can only occur within the '''larval''' or '''nymph''' stage of the tick, in which '''sporogony''' can occur. The infective stage is within the '''salivary glands''' of the following stage of the tick.
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The nymph or adult can then innoculate a mammalian host with the [[Protozoa | protozoan]].
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Because of its dependence upon the tick, transmission of Theileriosis is also affected by environmental and seasonal conditions. These will vary with geographical location.
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''Haemaphysalis'', ''Rhipicephalus'' and ''Dermacentor'' [[Ticks | tick]] species are all commonly implicated.
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For more information on ticks as vectors, see [[Tick Disease Transmission]]
      
In endemic areas, '''endemic stability''' is often reached, in which most or all cattle may be infected and be carriers and most ticks are also infected, but young calves gain solid immunity from their immune dams and therefore rarely show clinical disease. This state however takes time to stabilise and will cause significant economic losses in the process.
 
In endemic areas, '''endemic stability''' is often reached, in which most or all cattle may be infected and be carriers and most ticks are also infected, but young calves gain solid immunity from their immune dams and therefore rarely show clinical disease. This state however takes time to stabilise and will cause significant economic losses in the process.
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