title: Selection of porcine oocytes in vitro through brilliant cresyl blue staining in distinct incubation media.
abstract: Staining with brilliant cresyl blue (BCB) may be used for oocyte selection, but BCB staining itself and the most commonly used selection medium (DMPBS) may compromise the development of porcine oocytes in vitro. This study evaluated DNA fragmentation, nuclear maturation, the area of migration of cortical granules (CG) and embryo development for stained (BCB+) and unstained (BCB-) oocytes incubated in DMPBS and in a modified medium (ReproPel) tested for the first time. Unexposed (UN), BCB+ and BCB- oocytes were incubated composing six groups: DMPBS/UN; DMPBS/BCB+; DMPBS/BCB-; ReproPel/UN; ReproPel/BCB+; and ReproPel/BCB-. There were more BCB+ oocytes in ReproPel than in DMPBS (P < 0.05). The DNA fragmentation was evaluated for oocytes in DMPBS/BCB+, DMPBS/BCB-, ReproPel/BCB+, ReproPel/BCB- and in porcine follicular fluid (control). The frequency of oocytes with no DNA fragmentation was greatest (64.6%) in DMPBS/BCB+ and lowest in ReproPel/BCB+ and ReproPel/BCB- (26.8 and 34.1%, respectively) (P < 0.05). Nuclear maturation rates were greater (P < 0.05) for DMPBS/BCB+ (63.1%), ReproPel/UN (55.1%) and ReproPel/BCB+ (50.2%) than for DMPBS/UN (40.8%) and ReproPel/BCB- (35.5%). The area of CG was greater (P < 0.05) for ReproPel/BCB- (80.7%) and DMPBS/UN (77.6%) than for ReproPel/UN (34.7%). Cleavage rates for DMPBS/BCB+ and ReproPel/BCB+ were greater than for DMPBS/UN (P < 0.05). Blastocyst development rates were greatest (P < 0.05) for ReproPel/UN and ReproPel/BCB+. In both media, BCB staining was apparently unable to select competent oocytes, which likely occurred due to toxicity. Despite the similar nuclear maturation and area of CG compared with DMPBS, oocytes selected in ReproPel presented impaired DNA integrity.
authors.affiliation: ReproPel,Universidade Federal de Pelotas,96010-900,Pelotas,RS,Brazil.
authors.forename: Elisa C S
authors.initials: EC
authors.lastname: Santos
authors.affiliation: ReproPel,Universidade Federal de Pelotas,96010-900,Pelotas,RS,Brazil.
authors.forename: Jorgea
authors.initials: J
authors.lastname: Pradieé
authors.affiliation: ReproPel,Universidade Federal de Pelotas,96010-900,Pelotas,RS,Brazil.
authors.forename: Elisângela M
authors.initials: EM
authors.lastname: Madeira
authors.affiliation: Embrapa Clima Temperado,96010-900,Pelotas,RS,Brasil.
authors.forename: Miriane M
authors.initials: MM
authors.lastname: Pereira
authors.affiliation: ReproPel,Universidade Federal de Pelotas,96010-900,Pelotas,RS,Brazil.
authors.forename: Bruna
authors.initials: B
authors.lastname: Mion
authors.affiliation: ReproPel,Universidade Federal de Pelotas,96010-900,Pelotas,RS,Brazil.
authors.forename: Rafael G
authors.initials: RG
authors.lastname: Mondadori
authors.affiliation: ReproPel,Universidade Federal de Pelotas,96010-900,Pelotas,RS,Brazil.
authors.forename: Arnaldo D
authors.initials: AD
authors.lastname: Vieira
authors.affiliation: Embrapa Clima Temperado,96010-900,Pelotas,RS,Brasil.
authors.forename: Ligia M C
authors.initials: LM
authors.lastname: Pegoraro
authors.affiliation: ReproPel,Faculdade de Veterinária,Universidade Federal de Pelotas,96010-900-Pelotas-RS,Brazil.
authors.forename: Thomaz
authors.initials: T
authors.lastname: Lucia
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology; D002478:Cells, Cultured; D004396:Coloring Agents; D003470:Culture Media / Q000737:chemistry*; D053938:DNA Fragmentation; D005260:Female; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods*; D009152:Mutagenicity Tests / Q000379:methods; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D010078:Oxazines; D010312:Parthenogenesis; D013552:Swine
chemical_list: D004396:Coloring Agents; D003470:Culture Media; D010078:Oxazines; C006797:Brilliant Cresyl Blue
keywords: DNA fragmentation; Maturation; Media; Porcine oocytes; Toxicity