Methods to improve the health of cattle in the tropics: immunisation and chemoprophylaxis against haemoparasitic infections.

A study of methods to improve the health of native cattle in tropical areas of Colombia showed an advantage using immunisation techniques against haemoparasitic infections in comparison with other control methods. The control of anaplasmosis and babesiosis by immunisation of cattle with fully virulent Anaplasma marginale, Babesia argentina and B. bigemina is feasible in tropical cattle when the postimmunisation reaction is controlled by appropriate drug therapy. Chemoprophylaxis was found less effective in controlling haemoparasitic diseases; however, treated was found less effective in controlling haemoparasitic diseases; however, treated cattle surviving the acute stage of infection showed weight gains not significantly different from those of the immunised calves. Both methods were found to be advantageous with calves born and raised in an endemic area of anaplasmosis and babesiosis. Tick and gastrointestinal parasitic control without haemoparasitic control in calves had an advantage over no control system at all. These methods though were inferior to the immunisation and chemoprophylactic techniques.