title: Effects of re-stripping on the seminal characteristics of pacu (Piaractus mesopotamicus) during the breeding season.
abstract: Seminal characteristics in teleost fish with an annual reproductive period, such as pacu (Piaractus mesopotamicus), may vary during the breeding season. The sperm formed before the beginning of the spawning period may be stored for a long time, causing damage to the cells. Therefore, re-stripping may be an important way to eliminate the "old" and allow for the collection of "new" spermatozoids. In this study, we analyzed the seminal characteristics of hormonally induced pacu at the beginning, middle and end of the breeding season, and we analyzed samples from re-stripped males (stripped first at the beginning, re-stripped in the middle, and re-stripped again at the end of the season) during two breeding seasons. The sperm density, ionic composition, pH, and osmolality were similar among the groups. The semen volume, seminal plasma protein concentration and incidence of morphologically anomalous sperm increased over time. In addition, some parameters that are associated with good-quality semen decreased, such as sperm motility, viability and DNA integrity. Moreover, we observed a positive association among motility, viability and DNA integrity for sperm with elevated 11-ketotestosterone, but there was no such association for fshb or lhb mRNA levels in the pituitary. The semen that was obtained earlier (at the beginning) or from re-stripped males exhibited better characteristics than the other samples collected. In conclusion, collecting semen from pacu at the end of breeding season should be avoided; it is preferable to strip early and then re-strip later in the season, and this approach may be used for diverse aquaculture purposes.
authors.affiliation: Centro de Aquicultura da UNESP - CAUNESP, Universidade Estadual Paulista - UNESP, Via de Acesso Prof. Paulo Donato Castellane, S/N, 14884-900 Jaboticabal, SP, Brazil.
authors.forename: Rafael Y
authors.initials: RY
authors.lastname: Kuradomi
authors.affiliation: Centro de Aquicultura da UNESP - CAUNESP, Universidade Estadual Paulista - UNESP, Via de Acesso Prof. Paulo Donato Castellane, S/N, 14884-900 Jaboticabal, SP, Brazil.
authors.forename: Thiago G
authors.initials: TG
authors.lastname: De Souza
authors.affiliation: Centro de Aquicultura da UNESP - CAUNESP, Universidade Estadual Paulista - UNESP, Via de Acesso Prof. Paulo Donato Castellane, S/N, 14884-900 Jaboticabal, SP, Brazil; Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista - UNESP, Distrito de Rubião Júnior, S/N, 18618-970 Botucatu, SP, Brazil.
authors.forename: Fausto
authors.initials: F
authors.lastname: Foresti
authors.affiliation: Reproductive Biology Group, Division of Developmental Biology, Department of Biology, Faculty of Sciences, Utrecht University, Kruyt Building, Room W-606, Padualaan 8, NL-3584 CH Utrecht, The Netherlands.
authors.forename: Rüdiger W
authors.initials: RW
authors.lastname: Schulz
authors.affiliation: Reproductive Biology Group, Division of Developmental Biology, Department of Biology, Faculty of Sciences, Utrecht University, Kruyt Building, Room W-606, Padualaan 8, NL-3584 CH Utrecht, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Bogerd
authors.affiliation: Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo - USP, Rua do Matão, Travessa 14, n.321, Sala 220 Cidade Universitária, 05508-900 São Paulo, SP, Brazil.
authors.forename: Renata G
authors.initials: RG
authors.lastname: Moreira
authors.affiliation: Centro de Aquicultura da UNESP - CAUNESP, Universidade Estadual Paulista - UNESP, Via de Acesso Prof. Paulo Donato Castellane, S/N, 14884-900 Jaboticabal, SP, Brazil.
authors.forename: Luiz R
authors.initials: LR
authors.lastname: Furlan
authors.affiliation: Depto de Química e Ciências Ambientais, Universidade Estadual Paulista - UNESP, Rua Cristóvão Colombo, n.2265, Jardim Nazareth, 15054-000 São José do Rio Preto, SP, Brazil.
authors.forename: Eduardo A
authors.initials: EA
authors.lastname: Almeida
authors.affiliation: Depto de Química e Ciências Ambientais, Universidade Estadual Paulista - UNESP, Rua Cristóvão Colombo, n.2265, Jardim Nazareth, 15054-000 São José do Rio Preto, SP, Brazil.
authors.forename: Lucilene R
authors.initials: LR
authors.lastname: Maschio
authors.affiliation: Centro de Aquicultura da UNESP - CAUNESP, Universidade Estadual Paulista - UNESP, Via de Acesso Prof. Paulo Donato Castellane, S/N, 14884-900 Jaboticabal, SP, Brazil. Electronic address: batlouni@caunesp.unesp.br.
authors.forename: Sergio R
authors.initials: SR
authors.lastname: Batlouni
mesh_terms: D000818:Animals; D001947:Breeding; D060125:Characiformes / Q000502:physiology*; D008297:Male; D009994:Osmolar Concentration; D012621:Seasons; D012661:Semen / Q000378:metabolism*; D055101:Semen Analysis; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology*; D013094:Spermatozoa / Q000378:metabolism*; D013739:Testosterone / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D013739:Testosterone; C003600:11-ketotestosterone
keywords: DNA damage; Gonadotropins mRNA levels; Neotropical teleost fish; Semen quality; Spermiation; Steroid hormones