Ranking/grouping of Santa Ines ram frozen semen analyzed by casa and fluorescent probes lead through the multivariate statistics analysis/Ranqueamento/agrupamento do semen congelado de carneiros da raca Santa Ines analisadas pelo sistema casa e sondas fluorescentes pela analise estatistica multivariada

The cryopreservation process causes several alterations in semen quality, reducing fertility. New evaluations of sperm motility have been searched, such as the sperm subpopulations analysis by computer-assisted motility assessments (CASA). Fluorescent probes have been studied to evaluate spermatozoon integrity, supplying functional information of the spermatozoa. The aim of this study was to optimize the CASA system in combination with fluorescent probes as a new method of evaluation of the qualitative parameters of the frozen semen of rams. Twenty-six frozen semen samples were evaluated by CASA and MITO Test. The cluster analysis was used with the VARIMAX rotation method and the grouping analysis was performed with Ward's method. The individual kinetics of each spermatozoon was considered for the analysis, extending samples from 26 averages to 5834 spermatozoa. For the MITO test, the samples were grouped into eight categories. The multivariate exploring technique pointed out reduction of the dimensionality, leading to three factors: F1 factor interpreted as a factor related to the forward movement; F2 factor represents a factor of sperm displacement without considering the movement direction; F3 factor means the energy available for the sperm displacement. The determination of score coefficients of the factors was determined by grouping the samples into 9 subpopulations, with distinct qualitative characteristics. With the use of the multivariate statistics analysis of the frozen semen of the rams, it was possible to determine physiological and kinematics differences of the subpopulations associated to the fluorescent probes in the CASA system, with correlations between the CASA system and the MITO test. Keywords: sperm subpopulation, cryopreservation of ram semen, computer-assisted semen motility analysis (CASA), mitochondrial activity, fluorescent probes O processo de criopreservacao acarreta uma serie de alteracoes resultando em uma marcante reducao da fertilidade. Buscam-se novas formas de avaliacao do movimento espermatico, tais como a analise das sub-populacoes espermaticas pelo sistema CASA. Sondas fluorescentes vem sendo estudadas para avaliacao da integridade do espermatozoide, fornecendo informacoes adicionais sobre sua funcionalidade. Tem se como objetivo otimizar o emprego do sistema CASA em combinacao de sondas fluorescentes como nova forma de avaliacao dos parametros qualitativos do semen congelado de ovinos. Em vinte e seis partidas de semen