Table 3.

In vivo live attenuated parasite used in vaccine against Babesia.

Vaccine component	Efficacy	Reference
South African S24 vaccine attenuated strain (with 24 passages in cattle) of B. bovis	Vaccination conferred protection in cattle and the attenuated strain was not transmissible by ticks. Co-transmission of the attenuated strain together with field strains resulted in the emergence of a new transmissible parasite population with a distinct hybrid genotype.	(166, 167)
Australian B. bovis vaccine attenuated strains (Ka strain), was produced by rapid 20–30 passages in cattle.	This strain is used as a component of a trivalent live vaccine which also contains an attenuated B. bigemina Australian strain, and Anaplasma centrale which adds protection against Anaplasma marginale.	(54)
Test the infectivity of a vaccinal and a pathogenic strain of Babesia bovis for the tick Boophilus microplus. Vaccine strainR1A isolated from clinical case and attenuated and produced by 30 passages in splenectomised cattle. Pathogenic strain of B. bovis S2P isolated from splenectomised calf infected naturally via tick larvae by B. bovis.	Engorged female ticks fed on calves inoculated with the S2P strain were able to transmit the infection to splenectomised calves. This vaccine strain was shown not to be transmissible by ticks under natural conditions.	(168)
Attenuated B. bigemina (in vivo and in vitro) were used to vaccinate two groups of Holstein Friesian heifers. Another group of heifers was vaccinated twice with purified soluble antigens obtained from the supernatant of in vitro culture combined with saponin.	Heifers vaccinated with attenuated B. bigemina either in vivo or in vitro resisted challenge without specific treatment, whereas the opposite occurred in heifers group vaccinated with culture soluble antigens. Antibody titers were higher in heifers inoculated with soluble antigens than in heifers inoculated with in vivo live B. bigemina, suggesting that antibody titers may not be a proper indicator of animal protection.	(169)
An australian B. bigemina vaccine strain (G strain) of reduced virulence was tested in animal against a virulent South African strain	The strain caused mild reactions in 10 animals and afforded good protection to challenge with a virulent strain.	(170)
An Australian vaccine strains (including B. bovis, B. bigemian and A. marginale) was test their safety in pregnant Holando heifers and their efficacy against challenge from inoculated local field strains of the three parasites from Paraguay	The Babesia strains, but not A. marginale, provided good protection against field challenge and were safe to be used in highly susceptible cattle.	(171)