Spermatic abnormalities of piracanjuba Brycon orbignyanus (Valenciennes, 1849) after cryopreservation

Abstract

The objective of this research was to verify the presence of spermatic abnormalities on semen of Brycon orbignyanus after cryopreservation. Semen was collected from ten four-year-old males who presented secondary reproductive characteristics for migrating fish. Sperm was evaluated for motility, vigor and spermatic morphology before and after cryopreservation. A cryoprotectant solution was made of 20 mL of yolk egg, 5.0 g of glucose and dimethyl sulfoxide diluted in distilled water (10 mL: 90 mL). The diluted semen (1:3, semen:solution) was submitted to nitrogen steam for 24 hours and then to liquid nitrogen (-196 °C) for 60 days. Cryopreservation decreased the percentage of normal spermatozoa from 62.20% to 54.60%. Consequently, the percentage of spermatozoa with secondary abnormalities increased from 8.50% to 15.00%. However, there was no difference in primary abnormalities. Both spermatic motility and vigor were decreased in cryopreserved semen compared with fresh semen. In conclusion, cryopreservation of semen of B. orbignyanus increased the percentage of secondary abnormalities and decreased the spermatic motility and vigor.Keywords: freezing, spermatozoa, morphology, Bryconinae. Anormalidades espermáticas de piracanjuba Brycon orbignyanus(Valenciennes, 1849) após a criopreservação ResumoO objetivo deste trabalho foi verificar a presença de anormalidades espermáticas no sêmen de Brycon orbignyanus após a criopreservação. Dez machos com quatro anos de idade e que apresentavam características reprodutivas secundárias para peixes migradores tiveram o sêmen coletado. O sêmen foi avaliado através da motilidade, vigor e morfologia espermática antes e após a criopreservação. A solução crioprotetora continha 20 mL de gema de ovo, 5,0 g de glicose e dimetil sulfóxido diluído em água destilada (10 mL: 90 mL). O sêmen diluído (1:3, sêmen:solução) foi submetido ao vapor de nitrogênio por 24 horas e então ao nitrogênio líquido (-196 °C) por 60 dias. A criopreservação reduziu o percentual de espermatozoides normais de 62,20% para 54,60%. Consequentemente, o percentual de espermatozoides com anormalidades secundárias aumentou de 8,50% para 15,00%. Porém, não foi observada diferença nas anormalidades primárias no sêmen "in natura" e pós-criopreservação. Ambos motilidade e vigor espermático foram inferiores aos observados no sêmen "in natura". Conclui-se que a criopreservação do sêmen de B. orbignyanus aumentou o percentual de anormalidades secundárias e reduziu a motilidade e o vigor espermático.Palavras-chave: congelação, espermatozoide, morfologia, Bryconinae.

Use of glucose or BTS"! combined with DMSO or methylglycol under two different freezing protocols for the cryopreservation of sperm from the common curimatã (Prochilodus brevis)

“…The data obtained from the fresh and post-thawed sperm were then compared. The damaged observed in the spermatozoa were classified according to Galo et al (2011 The following treatments were applied: (T1) glucose+10% DMSO, (T2) glucose+10% MG, (T3) BTS™+10% DMSO and (T4) BTS™+10% MG. The total semen of each male (n = 8 males) was diluted (1:6 semen:extender) in all of the treatments and loaded in 0.25-ml straws (n = 6 replicate straws per treatment and per male), identified, sealed at the ends with polyvinyl alcohol, and maintained at 10ºC for 10 min.…”

Effects of cooling rates on the quality of Prochilodus lineatus (Valenciennes, 1836) sperm

“…Moraes et al (), Murgas, Silva, Mello, Santana, and Kabeya () and Miliorini et al () estimated 9.54%, 40.2% and 3% of total alterations in fresh P. lineatus sperm, respectively. Galo et al () observed the degenerate tails and free head morphologies increased from 11.47% to 22.89% and from 3.70% to 40.80% in fresh and cryopreserved Brycon orbignyanus sperm, respectively. The morphological analysis of fish spermatozoa, thus, presents species‐specific, genetic and environmental variations.…”

Cryopreservation‐induced morphological changes in the sperm of South American silver catfish ( Rhamdia quelen )

“…Numerous authors classify sperm abnormalities as primary and secondary (Galo et al, ; Miliorini et al, ; Rocha et al, ; Streit Jr., ), based on the classification used for mammals, where the primary alterations are related to spermatogenesis and the secondary with environmental factors and reproductive management. However, Streit Jr. et al () report an increase in the occurrence of primary morphological alterations after cryopreservation, indicating that these abnormalities in sperm cells of fish can be caused by the cryopreservation process and not by spermatogenesis.…”

“…The sperm quality is fundamental to the process of artificial reproduction, directly reflecting the success of fertilization and the parameters of sperm motility and morphology are often used as indicators of sperm quality (Figueroa, Valdebenito, & Farias, 2016;Galo et al, 2011;Sanches et al, 2013;Soares, Streit, Ebert, Coldebella, & Oberst, 2010). Motility is essential for fertilization and usually manifests a positive correlation with the fertilization capacity (Figueroa et al, 2016;Sanches et al, 2013).…”