02097naa a2200301 a 450000100080000000500110000800800410001902400320006010000200009224501100011226000090022252012260023165000160145765000150147365300270148865300110151565300190152665300150154565300200156070000160158070000120159670000230160870000230163170000260165470000290168070000230170977300630173221167732019-12-12       2019    bl uuuu     u00u1 u    #d7 a10.28951/rbb.v37i1.3412DOI1 aMAIORANO, A. M.  aComparative study of cattle tick resistance using generalized linear mixed models.h[electronic resource]  c2019  aComparison of tick resistance in Bos taurus indicus (Nelore) and Bos taurus taurus (Simmental and Caracu) subspecies was investigated utilizing generalized linear mixed models (GLMMs) with Poisson and Negative binomial distributions. Nelore animals (NE) are known to present greater resistance than B. t. taurus. Difference between tick resistance in Simmental (SI) and Caracu (CA) breeds has never been reported previously. Three artificial tick infestations were conducted to evaluate tick resistance in these breeds. The statistic point of the present study was to show alternative models for the evaluation of tick count data, the GLMMs. Analysis for tick resistance by GLMM with Negative binomial distribution has never been assessed previously. The analyses were performed by the use of the PROC GLIMMIX procedure of the SAS program. The results showed that GLMM with Negative binomial distribution is appropriated to evaluate tick count data with excess of zero observations avoiding overdispersion problems. Finally, considering multiple comparisons with the Bonferroni test, different pattern of tick infestation was observed for the studied breeds, suggesting that NE is the most resistant breed followed by CA.  aBos Indicus  aBos Taurus  aArtificial infestation  aNelore  aSkin thickness  aTick count  aTick resistance1 aMOTA, T. S.1 aVERDUGO1 aFARIA, R. A. da S.1 aSILVA, B. P. M. da1 aOLIVEIRA, M. C. de S.1 aCYRILLO, J. N. dos S. G.1 aSILVA, J. A. de V.  tRevista Brasileira de Biometriagv.37, n.1, p.41-55, 2019.