Caracterização das subpopulações espermáticas do Tambaqui e sua correlação com a fertilidade

• Ano de defesa: 2014
• Autor(a) principal: Cavalcante, Sidney Sales
• Orientador(a): Maria, Alexandre Nizio
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Programa de Pós-Graduação: Pós-Graduação em Zootecnia
• Palavras-chave em Português: Zootecnia; Tambaqui (Peixe); Criopreservação; Peixes; Fecundidade; Motilidade; Colossoma macropomum
• Palavras-chave em Inglês: Cryopreservation; Fishes; Tambaqui
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA
• Link de acesso: https://ri.ufs.br/handle/riufs/6364

The analysis of sperm subpopulations is a relatively new approach that consists of evaluating the coexistence of different sperm grouped by similarity. This characterization allows us to explore the heterogeneity of existing sperm in a semen sample, so it is revealed your fertility potential. The aim of this study was to identify and characterize sperm subpopulations in semen tambaqui (C. macropomum) regarding the kinetics and evaluate its correlation with fertility, as well as analyzing the changes arising from the cryopreservation process in the distribution of sperm subpopulations. 59 767 sperm semen in natura and 50,680 of the thawed sperm of 61 fish through analysis in a computerized system (CASA) were evaluated. The kinetic data generated sperm were tabulated, analyzed, and evaluated relativized by the method of analysis of two-step cluster grouping. For correlation with fertilization, 15 animals with distinct sperm qualities were selected and evaluated for their performance in fertilization from seminal fresh samples. These procedures allowed the identification of three sperm subpopulations in semen in natura tambaqui, two of which are highly correlated with fertility. The first subpopulation corresponded to 28.81% of the total analyzed sperm and it was less abundant. Low values of curvilinear velocity - VCL: 58.92 mM / s, linearity - LIN: 23.15%, straightness - STR: 40.01% and beat cross frequency - BCF: 6.79 Hz characterized the sperm of this subpopulation as slow progressive non-linear and not, where no significant correlation was observed with fertility (r = 0.28). The second subpopulation represented 31.61% of the examined spermatozoa which were classified as rapid, non-linear, non-progressive and high beat cross frequency (LCV: 114.10 mM / s, LIN: 46.77% STR: BCF and 59.17%: 21.49 Hz), high positive correlation was observed with fertility (r = 0.93). Already a subpopulation 3, had a higher percentage of sperm analyzed (39.58%), characterized as fast, linear, progressive and high beat cross frequency (VCL: 134.11 mM / s, LIN: 81.41%, STR : BCF and 86.57%: 26.73 Hz), being also observed high positive correlation with fertility (r = 0.79). After thawing semen tambaqui, we could identify only two sperm subpopulations with distinct heterogeneity. The first subpopulation, representing 33.24% of the analyzed sperm which were characterized as slow, non-linear, non-progressive and low beat cross frequency (VCL: 52.96 mM / s, LIN: 20.70%, STR: and 41.70% BCF: 5,61Hz). The second subpopulation corresponded to 66.76% of the analyzed sperm which were characterized as fast, linear, progressive and high beat cross frequency (VCL: 121.57 mM / s, LIN: 69.02%, STR: 77, and 09% BCF: 26.00 Hz). It is concluded that semen tambaqui has three sperm subpopulations characterized by movement pattern, two of which are represented by rapid sperm directly related to fertility. The cryopreservation process reduces the number of sperm subpopulations and alters the pattern of linearity and progressivity of spermatozoa.