Ravagnani, Gisele M.Torres, Mariana A.Leal, Diego F.Martins, Simone M. M. K.Papa, Frederico O. [UNESP]Dell'Aqua Junior, Jose A. [UNESP]Alvarenga, Marco A. [UNESP]Andrade, Andre F. C.2019-10-042019-10-042018-09-01Pesquisa Veterinaria Brasileira. Rio Janeiro: Revista Pesquisa Veterinaria Brasileira, v. 39, n. 9, p. 1726-1730, 2018.0100-736Xhttp://hdl.handle.net/11449/185034To date, no studies have been performed evaluating the effect of boar spermatozoa concentration in 0.5mL freezing straws, leading us to examine this question. Each sperm-rich fraction of the ejaculate (n=25) was diluted at five different sperm concentrations (100, 200, 300, 600 and 800 x 10(6) spermatozoa/mL), packaged in 0.5mL straws, and subsequently frozen. After thawing, the sperm from all of treatment groups were analyzed to determine motility characteristics using a sperm class analyzer (SCA-CASA), and their plasma and acrosomal membrane integrity, mitochondria! membrane potential, sperm membrane lipid peroxidation and fluidity were analyzed by flow cytometry. An increase in spermatozoa concentration above 300x10(6) spermatozoa/mL in a 0.5mL straw impaired (p<0.05) the total and progressive motility, curvilinear velocity, straight-line velocity, linearity and beat cross frequency. However, the plasma and acrosomal membrane integrity, mitochondria] membrane potential, membrane lipid peroxidation and fluidity were not influenced (p>0.05) by high spermatozoa concentrations at freezing. Therefore, to increase spermatozoa survival and total and progressive motility after thawing, boar spermatozoa should be frozen at concentrations up to 300x10(6) spermatozoa/mL.1726-1730engCryopreservationboar semenspermatozoa concentrationsperm viabilitycryoinjurycryocapacitationswineArtigo10.1590/1678-5150-PVB-5465S0100-736X2018000901726WOS:000449559300003Acesso abertoS0100-736X2018000901726.pdf