title: The administration of exogenous prostaglandin may improve ovulation in pacu (Piaractus mesopotamicus).
abstract: Based on the reports of unsuccessful ovulation in pacu (Piaractus mesopotamicus) by fish farmers and researchers undertaking artificial reproduction programs, we evaluated the use of prostaglandin F (PGF) to improve pacu ovulation. This study was conducted during two spawning seasons (2009/2010 and 2010/2011) with two samplings in the first season and one sampling in the second season. A total of 45 females was sampled in this study. The control group was injected with carp pituitary extract (crude extract, 6 mg/kg), and the treatment group received PGF (2 mL per fish in the 2009/2010 season and 5 mL per fish in the 2010/2011 season) in addition to the crude extract. In both seasons, 100% (N = 4, 2009/2010 first sampling; N = 5, 2009/2010 second sampling; and N = 3, 2010/2011) of the PGF-treated fish spawned. In contrast, 53.0% (N = 9) and 83.3% (N = 10) of the control fish spawned in the first and second samplings of the 2009/2010 season, respectively, and only 25.0% (N = 1) spawned in the 2010/2011 season. Fecundity, fertility, and hatching rates did not differ (P > 0.05) between the treated and control fish. Based on oocyte volume frequency analysis, ovaries of the control fish had more (P < 0.05) vitellogenic oocytes with germinal vesicle breakdown that remained unovulated after spawning, whereas more (P < 0.05) of previtellogenic oocytes were present in the ovaries of the PGF-treated fish. In conclusion, administration of exogenous prostaglandin may improve the outcome of hormonally induced spawning in tropical migratory fish.
authors.affiliation: University of Sao Paulo State (UNESP), Aquaculture Centre of UNESP (CAUNESP), Jaboticabal, Sao Paulo, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Criscuolo-Urbinati
authors.forename: R Y
authors.initials: RY
authors.lastname: Kuradomi
authors.forename: E C
authors.initials: EC
authors.lastname: Urbinati
authors.forename: S R
authors.initials: SR
authors.lastname: Batlouni
mesh_terms: D000818:Animals; D060125:Characiformes / Q000502:physiology*; D005260:Female; D008297:Male; D010060:Ovulation / Q000187:drug effects* / Q000502:physiology*; D011460:Prostaglandins F / Q000494:pharmacology*; D012098:Reproduction / Q000187:drug effects / Q000502:physiology
chemical_list: D011460:Prostaglandins F