Trypan blue staining is not efficient in determining oocyte viability in Colossoma macropomum and Brycon amazonicus / Coloração com azul de tripan não é eficiente na determinação da viabilidade de oócitos em Colossoma macropomum e Brycon amazonicus

Currently, there is no effective technique to evaluate the quality of oocytes in fish farming in apractical and affordable way. The cell membrane integrity test with the vital dye trypan blue (TB)could be an option. In this study, Colossoma macropomum and Brycon amazonicus oocytes were exposed to different TB concentrations seeking to verify a possible relationship between the results of staining tests and reproductive rates. Oocytes were exposed to concentrations of 0.05, 0.04, 0.03, 0.02 and 0.01% TB for 1 minute and subsequently were evaluated under a stereomicroscope. The percentage of unstained (viable) oocytes from each sample was correlated with fertilization and hatching rates using a linear regression (P>0.05). We observed a weak correlation between the results of the staining tests and the fertilization and hatching rates in both species. TB integrity tests were not effective in predicting spawning viability in C. macropomum and B. amazonicus.(AU)

Atualmente não existem técnicas efetivas para avaliar a qualidade de oócitos na piscicultura deforma prática e acessível. O teste de integridade da membrana celular com corante vital azul detripan (AT) surge como uma alternativa. Nesse estudo, oócitos de Colossoma macropomum e Bryconamazonicus foram expostos a diferentes concentrações de AT, buscando verificar uma possível relação entre os resultados dos testes de coloração e as taxas reprodutivas. Oócitos foram expostos a concentrações de 0,05; 0,04; 0,03; 0,02 e 0,01% de AT durante 1 minuto e, posteriormente avaliados em estereomicroscópio. A porcentagem de oócitos não corados (intactos) de cada amostra foicorrelacionada com as taxas de fertilização e eclosão utilizando análise de regressão linear (P>0,05). Fraca correlação entre resultados dos tratamentos e as taxas de fertilização e eclosão nas duas espécies foi observada. Os testes de integridade com AT foram ineficazes em predizer o sucesso da desova em C. macropomum e B. amazonicus(AU)

Trypan blue staining is not efficient in determining oocyte viability in Colossoma macropomum and Brycon amazonicus / Coloração com azul de tripan não é eficiente na determinação da viabilidade de oócitos em Colossoma macropomum e Brycon amazonicus

Currently, there is no effective technique to evaluate the quality of oocytes in fish farming in apractical and affordable way. The cell membrane integrity test with the vital dye trypan blue (TB)could be an option. In this study, Colossoma macropomum and Brycon amazonicus oocytes were exposed to different TB concentrations seeking to verify a possible relationship between the results of staining tests and reproductive rates. Oocytes were exposed to concentrations of 0.05, 0.04, 0.03, 0.02 and 0.01% TB for 1 minute and subsequently were evaluated under a stereomicroscope. The percentage of unstained (viable) oocytes from each sample was correlated with fertilization and hatching rates using a linear regression (P>0.05). We observed a weak correlation between the results of the staining tests and the fertilization and hatching rates in both species. TB integrity tests were not effective in predicting spawning viability in C. macropomum and B. amazonicus.

Atualmente não existem técnicas efetivas para avaliar a qualidade de oócitos na piscicultura deforma prática e acessível. O teste de integridade da membrana celular com corante vital azul detripan (AT) surge como uma alternativa. Nesse estudo, oócitos de Colossoma macropomum e Bryconamazonicus foram expostos a diferentes concentrações de AT, buscando verificar uma possível relação entre os resultados dos testes de coloração e as taxas reprodutivas. Oócitos foram expostos a concentrações de 0,05; 0,04; 0,03; 0,02 e 0,01% de AT durante 1 minuto e, posteriormente avaliados em estereomicroscópio. A porcentagem de oócitos não corados (intactos) de cada amostra foicorrelacionada com as taxas de fertilização e eclosão utilizando análise de regressão linear (P>0,05). Fraca correlação entre resultados dos tratamentos e as taxas de fertilização e eclosão nas duas espécies foi observada. Os testes de integridade com AT foram ineficazes em predizer o sucesso da desova em C. macropomum e B. amazonicus

Technique to simultaneously evaluate ram sperm morphology, acrosome and membrane integrity

Several laboratory methods to evaluate ram sperm quality have been developed. The combination of different fluorescent probes is suitable to simultaneously evaluate different sperm characteristics but the need fora fluorescent microscope restricts its use. The Aim of the present study was to evaluate the efficacy of Hypoosmotic Trypan Blue Giemsa (HTBG) staining to simultaneously detect sperm morphological abnormalities, plasma and acrosomal membrane integrity using phase contrast and fluorescence microscopy as the gold standards. Samples from twelve fresh ejaculates from three rams (4 ejaculates/ram) were used in the study. Sperm cells were evaluated using HTBG, phase contrast (PC) and fluorescent (FLUO) techniques. HTBG was more effective in detecting sperm defects when compared to PC (P < 0.05). No significant differences (P > 0.05) were observed between HTBG and FLUO in the assessment of plasmatic membrane and acrosome integrity. High correlation between HTBG and FLUO techniques was observed when assessing plasma membrane and acrosome (R = 0.97 and 0.96, respectively). In conclusion, the HTBG staining is suitable to assess ram sperm morphology, plasma and acrossomal membrane integrity simultaneously.(AU)

Technique to simultaneously evaluate ram sperm morphology, acrosome and membrane integrity

Several laboratory methods to evaluate ram sperm quality have been developed. The combination of different fluorescent probes is suitable to simultaneously evaluate different sperm characteristics but the need fora fluorescent microscope restricts its use. The Aim of the present study was to evaluate the efficacy of Hypoosmotic Trypan Blue Giemsa (HTBG) staining to simultaneously detect sperm morphological abnormalities, plasma and acrosomal membrane integrity using phase contrast and fluorescence microscopy as the gold standards. Samples from twelve fresh ejaculates from three rams (4 ejaculates/ram) were used in the study. Sperm cells were evaluated using HTBG, phase contrast (PC) and fluorescent (FLUO) techniques. HTBG was more effective in detecting sperm defects when compared to PC (P 0.05) were observed between HTBG and FLUO in the assessment of plasmatic membrane and acrosome integrity. High correlation between HTBG and FLUO techniques was observed when assessing plasma membrane and acrosome (R = 0.97 and 0.96, respectively). In conclusion, the HTBG staining is suitable to assess ram sperm morphology, plasma and acrossomal membrane integrity simultaneously.