02033naa a2200313 a 450000100080000000500110000800800410001910000190006024501380007926000090021752011400022665000240136665000160139065000150140665000140142165000190143565000110145470000160146570000200148170000140150170000170151570000200153270000190155270000150157170000210158670000200160770000270162777300650165420943632018-08-21       2005    bl uuuu     u00u1 u    #d1 aKASHINO, S. S.  aBoophilus microplusbthe pattern of bovine immunoglobulin isotype responses to high and low tick infestations.h[electronic resource]  c2005  aCattle present variable levels of resistance to ticks and the immune correlates of these heritable phenotypes must be known in order to develop eVective vaccines. The antibody responses to tick salivary antigens were examined in cattle of tick-susceptible (Holstein) and tick-resistant (Nelore) breeds. After heavy infestations, levels of IgG1 and IgG2 antibodies decreased in Holsteins and remained the same in Nelores. Conversely, levels of IgE antibodies increased in Holsteins. DiVerent sizes of tick burdens modulated the IgG1 antibody response in a susceptible breed (Aberdeen): levels were higher than in controls in heavily infested animals, but not in those undergoing intermediary or minimal infestations. The three experimental groups presented similar levels of IgG2 antibodies. Levels of IgE antibodies were higher only in animals undergoing intermediate infestations. These results indicate that tick infestations suppress the IgG antibody response in susceptible breeds, that IgE antibodies are not protective, and that the dose of tick saliva modulates the isotype of host antibody responses. Published by Elsevier Inc.  aBoophilus Microplus  aBos Indicus  aBos Taurus  aCarrapato  aImunoglobulina  aSaliva1 aRESENDE, J.1 aSACCO, A. M. S.1 aROCHA, C.1 aPROENÇA, L.1 aCARVALHO, W. A.1 aFIRMINO, A. A.1 aQUEROZ, R.1 aBENAVIDES, M. V.1 aGERSHWIN, L. J.1 aSANTOS, I. K. F. de M.  tExperimental Parasitologygv. 110, n. 1, p. 12-21, May 2005.