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Vitrification, Domestic cat, Testicular tissue, cryoprotectants, Vitrification techniques
The objective is to investigate the effect of different associations of intracellular and extracellular cryoprotective agents in vitrification of pubertal domestic cats (Felis catus) testicular tissue, as well as determine the most viable vitrification technique for the tests tissue of these animals. The study was divided into two stages. In step 1, the effects caused by the use of 40% ethylene glycol (EG) or the association with dimethylsulfoxide (DMSO) (20% EG + 20% DMSO), plus 0.1M or 0.5M sucrose or trehalose were evaluated by histological morphology of germ cells, Sertoli cells and measurements of seminiferous tubules analysis after vitrification. In step 2, the vitrification techniques on solid surface (SSV), conventional pallets and Ovarian Tissue Cryosystem (OTC) will be evaluated to determine the most viable method to preserve morphological integrity, cell viability and apoptotic index of cells in the testicular tissue of domestic cat. In step 1, the preliminary results showed that the Sertoli sperm and cells showed no difference with the use of the two sugars in the different concentrations, however, the morphological integrity was more compromised when the DMSO was used.