Colossoma macropomum females can reproduce more than once in the same reproductive period

Abstract

The aim of the present study was to evaluate induced reproduction in Colossoma macropomum females at the beginning of the reproductive period and 75 days after the first spawning in which reproduction was induced. The experiment was conducted in Nova Mutum, MT, Brazil. Eight 4-year-old C. macropomum females with an average body weight of 6.7 ± 2.4 kg were used. Hormonal induction was performed at the beginning of the reproductive period and repeated 75 days after the first spawning. The following variables were then evaluated: weight of released oocytes, production index, absolute fecundity, oocyte diameter, fertilization rate, and hatching rate. Of the eight females that spawned during the first hormonal induction, three (37.5%) spawned again 75 days after the first spawning. Two females died after the first induced spawning. None of the means of the evaluated variables differed between the two induced spawnings, except for fertilization rate, which was greater (P < 0.05) with the first spawning (88.8 ± 6.1%) than in the second (74.1 ± 10.4%). The results of the present study indicate that C. macropomum females can reproduce again 75 days after a first induced spawning.

Resumption and progression of meiosis and circulating levels of steroids and prostaglandin F 2α of Piaractus mesopotamicus induced by hypophysation with prostaglandin F 2α

“…However, we observed that, for unknown reasons, at the time of ovulation, some few females with high plasma levels of PGF 2α , equal to those of successful ovulated females, show failures in ovulation (delayed and insufficient), indicating that the levels of PGF 2α at the time of ovulation did not fully explain the reasons for successful and inadequate ovulation in this species (Kuradomi & Batlouni, 2018). The reasons associated with the individual failures of some females of this species remain unknown, as well as for many other species of fish (Goetz & Theofan, 1979; Hainfellner et al., 2012; Jalabert & Szöllösi, 1975; Pires et al., 2018). However, in this study, we took an important step towards understanding this process in the pacu showing that (a) hypophysation with or without the use of exogenous PGF 2α caused a DHP plasma level peak 4 hr after the resolving the dose concomitantly with meiosis resumption; (b) the use of exogenous PGF 2α caused elevations of this substance in the plasma levels between 1–4 hr after the resolving hypophysation dose; and (c): hypophysation with or without the use of exogenous PGF 2α caused a second PGF 2α plasma peak, of lesser intensity than the first, at the expected spawning period in this species.…”

Utilização De Alimentadores De Auto-Demanda: Uma Revisão E Potencial Uso Para Peixes Amazônicos

“…A avaliação da qualidade dos gametas femininos é limitada pela estimativa das taxas de fertilização, eclosão e de larvas normais 78 além da estimativa do número total de oócitos produzidos 79 . Isso se deve principalmente em função da necessidade de fertilização imediata e/ou a curto tempo pós-extrusão, pois os oócitos perdem rapidamente a qualidade após a retirada das fêmeas 80 .…”

“…Pesquisas recentes têm mostrado que os peixes reofílicos podem retornar à reprodução após uma nova indução hormonal em um mesmo período reprodutivo, tais como observado para fêmeas de C. macropomum 79 . Neste sentido, talvez o controle de alguns fatores ambientais no laboratório permita obter mais reproduções ao longo do ano nas diferentes espécies reofílicas.…”

A Ostreicultura Enquanto Alternativa De Renda Para Populações Tradicionais Do Litoral Amazônico: O Caso Da Agromar

“…A avaliação da qualidade dos gametas femininos é limitada pela estimativa das taxas de fertilização, eclosão e de larvas normais 78 além da estimativa do número total de oócitos produzidos 79 . Isso se deve principalmente em função da necessidade de fertilização imediata e/ou a curto tempo pós-extrusão, pois os oócitos perdem rapidamente a qualidade após a retirada das fêmeas 80 .…”