Sperm cryopreservation of Prochilodus lineatus throughout the same reproductive season

Abstract

The aim of this study was to determine the effect of seasonality on post‐thaw sperm quality in Prochilodus lineatus. Sperm from 43 males was cryopreserved throughout the reproductive season (November–March). Fresh sperm quality, concentration, volume, seminal plasma pH, osmolality and ion concentration were analysed. Post‐thaw sperm was analysed for its motility rate, velocities, beat‐cross frequency, cell morphology, oxidative stress and fertilization capacity. Prochilodus lineatus fresh sperm yielded high‐quality during the reproductive period (motility >80%). Post‐thaw sperm quality changed throughout the season, with higher motility (63.2%–72.3%) and curvilinear velocity (VCL) (55.9–59.2 µm/s) from December to March. Sperm concentration was negatively correlated with post‐thaw sperm motility and VCL, and positively correlated with seminal plasma Ca2+ concentration, catalase activity (CAT) and reactive oxygen species (ROS). Seminal plasma Ca2+ was positively correlated with ROS and negatively correlated with post‐thaw sperm motility. Post‐thaw sperm CAT and fertility correlated positively. Although post‐thaw sperm quality was reduced in November, the increased CAT was efficient in maintaining its fertilization capacity. In order to face seasonal influence, the optimal period to cryopreserve P. lineatus spermatozoa is from December to March, when sperm exhibits characteristics which make spermatozoa more prone to resist cryodamage.

Spectrophotometric method for determination of Colossoma macropomum (tambaqui) sperm concentration

“…These variations in sperm concentration in individuals within the same genus or species are linked to the season (8,9) , nutritional status (3,34) , water quality (35) , animal weight (14) , and the type and dose of the hormone used (10,27) . For instance, in an experiment evaluating the reproductive performance of Brycon orbygnianus and Prochilodus lineatus treated with buserine extract, Paulino et al (10) found that this hormone inducer provided a more homogenous response in sperm concentration of P. lineatus compared with B. orbygnianus.…”

“…Sperm concentration can be used to assess the volume of fresh or post-thawed sperm that will be directed to artificial fertilization procedures, helping to determine the most suitable insemination dose (6,7) . It can be also employed to identify the range of sperm production during the breeding season (8,9) , the response to hormonal treatment (10) , and differences between bred and wild males (4) . Sperm concentration may be estimated by (a) sperm count using a hemocytometer, (b) spermatocrit reading, (c) flow cytometry, and (d) optical density by spectrophotometry.…”

Does semen quality of Colossoma macropomum change the productivity of larvae during the reproductive period?

“…Streit Jr. et al (2008) found high rates of sperm pathology in gilthead sea bream (Salminus maxillosus) semen quality parameters in captivity. Egger et al (2021) evaluating seminal parameters of Prochilodus lineatus between the November and March, observed higher sperm concentration in November, better motility rate in November, January and February, and longer duration of motility time in January.…”

Determinação da concentração espermática de tambaqui (Colossoma macropomum) por espectrofotometria

“…Anim. Bras., V24, e-74695P durante a estação reprodutiva (8,9) , a resposta ao tratamento hormonal (10) e as diferenças entre machos criados e selvagens (4) . A concentração espermática pode ser estimada por (a) contagem de espermatozoides usando um hemocitômetro, (b) leitura de espermatócrito, (c) citometria de fluxo e (d) densidade óptica por espectrofotometria.…”