Members of the genus Babesia are Apicomplexan parasites commonly referred to as the 'piroplasms'. They have a two-host life-cycle involving a tick and a mammal. In the mammalian host the organisms reproduces asexually. Out of at least six Babesia species that have a considerable impact on livestock health and productivity, two species, Babesia bovis and Babesia bigemini have the greatest affect. Both are transmitted by Boophilus species as tick vectors. Tick-fever or cattle-fever (bovine babesiosis) is economically the most important tick-borne disease of cattle worldwide. Many hundreds of millions of cattle worldwide are at risk from these organisms.

B. bigemina is distributed wherever Boophilus ticks are encountered, which includes North and South America, Southern Europe, Africa, Asia and Australia. In cattle disease caused by B. bigemina is also known as 'Texas cattle fever' or 'red-water fever'.

B. bigemina is a large Babesia species that is pleomorphic but often occur in pairs within the infected red blood cells, hence the name 'bigemina'. In cattle, the parasite can cause massive destruction of the red blood cells leading to severe anaemia and hemoglobinuria. This result in red urine (due to haemoglobin in urine) and the disease can kill a cow within a week. In susceptible British-bred cattle (Bos taurus), high levels of mortality can occur on first exposure.

Data Downloads

• FTP site

• BLAST server

[Genome Research Limited]