Reproductive biology ofPseudoplatystoma corruscans(Spix and Agassiz, 1829) andPseudoplatystoma reticulatum(Eigenmann and Eigenmann, 1889), two species of fisheries importance in the Cuiabá River Basin, Brazil

Abstract

The aim of this study was to compare the reproductive processes of two large catfishes, Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum, from the Cuiabá River Basin. The reproductive process were assessed to: (i) characterizing the population structure and sex ratio; (ii) determining the reproductive period; (iii) estimating and quantify the nutritional status and energy reserves and their relationships with reproductive stages; and (iv) estimating the body length at first gonad maturation (TL 50 ). Individuals were sampled monthly from July 2006 to February 2008 using gill nets, seine nets, hooks, casting nets and trotlines. In addition, 294 individuals were obtained from the artisanal fishery in the city of Cuiabá, Mato Grosso state, Brazil.Total lengths were greater for females for both species, with no significant difference in the sex ratio; growth was considered isometric, except for P. corruscans males. Peak reproductive activity was in December and January. Differences in the hepatosomatic index (HSI) in P. corruscans depended on the gender. In P. reticulatum the HSI did not differ between sexes or among developmental stages. For P. corruscans, the estimated mean total length at first maturity (TL 50 ) was 62.92 cm, and for P. reticulatum 57.84 cm.Action to ensure the protection of the fish stocks should consider their reproduction processes, which are important for the equilibrium of these populations in the Cuiabá River, as well as for fisheries management.

Population and reproductive parameters of the red-tailed catfish, Phractocephalus hemioliopterus (Pimelodidae: Siluriformes), from the Xingu River, Brazil

“…Sexual dimorphism was found in P. hemioliopterus, and has also been recorded in other pimelodids (Paschoalini et al, 2013;Suzuki et al, 2013;Barzotto et al, 2017). While the length did not vary between sexes, the female P. hemioliopterus were heavier than the males, presumably due to their greater energetic investment in the reproductive process, in particular, the production of eggs (Bromley, 2003;Prudente et al, 2014;Barneche et al, 2018).…”

“…A number of authors have also recognized the importance of the flood pulse for the reproduction of pimelodids (Holzbach et al, 2009;Suzuki et al, 2013;Barzotto et al, 2017). In the Amazon, in particular, many high-value species that migrate hundreds of kilometers in response to the seasonal flood pulse (e.g.…”

Reproductive biology of a Gobiid fish Oxyurichthys tentacularis (Valenciennes, 1837) inhabiting Ashtamudi Lake, S. India

“…Sex ratio of a fish may deviate from the normal 1:1 due to a number of factors such as, habitat preference, behavioral differences between sexes, differential fishing, differences in growth rate between sexes, differences in morphology and physiological activity (Barzotto, Oliveira, & Mateus, ). The higher percentage of males in the present study throughout the year may be related to a combination of several factors stated above (Alp, Kara, & Buyukcapar, ; Nikolsky, ).…”

Reproductive biology of female sawcheek scorpionfish, Brachypterois serrulata (Richardson, 1846) (Teleostei; Scorpaenidae) from Visakhapatnam Coast, India

“…Fecundity increases with the size of the female, in so far as larger fish produce significantly more eggs than smaller animals (Bagenal 1978). It should be noted that the fecundity of B. serrulata is rather low compared with other species from the Scorpaenidae whether they are typically oviparous species, such as Trigla lyra or zygoparous, such as Helicolenus dactylopterus, with the highest egg count of 8,7000 per female (Barzotto et al 2017;Kaim-Malka and Jacob 1985;. The fecundity of B. serrulata is determined by the size and weight of the individuals with a high degree of correlation.…”