Induced spawning and early ontogeny in hatchery-reared catfish Zungaro jahu (Siluriformes: Pimelodidae)

Abstract

Hatchery-kept catfish jahus Zungaro jahu (Ihering, 1898) were induced to spawn with carp pituitary extract. The telolecithal eggs were round (1.6 ± 0.1 mm in diameter), demersal, free, and covered with a 0.4 mm-thick jelly coat. The gonadosomatic index of 2.8 was comparable to that of other Pimelodidae. The number of eggs x g of ova-1 was 804 ± 144. Hatching occurred 14.5 h after fertilization, at a temperature of 27.3 ± 0.4º C. The newly-hatched embryos measured 3.9-4.3 mm of total length (TL). At 18 h post-hatching (HPH; 5.3 ± 0.1 mm TL), the retina was pigmented, the mouth opened and dorsoflexion of the notochord had initiated. At 36 HPH (6.4 ± 0.2 mm TL), fusiform chromatophores were vertically arranged in the primordial fin fold and the notochord was dorsoflexed. The yolk sac was almost exhausted by 48 HPH (7.3 ± 0.2 mm TL). At 128 HPH (8.6 ± 0.6 mm TL) the pectoral, dorsal, adipose, caudal, anal, and pelvic fins were readily observable whereas the primordial fin fold was no longer visible. At 224 HPH (16.6 ± 2.5 mm TL), the metamorphosis was completed and the larvae had acquired the juvenile appearance.

Induced spawning and reproductive variables of the catfish Lophiosilurus alexandri Steindachner, 1876 (Siluriformes: Pseudopimelodidae)

“…However, there are eggs that have a gelatinous coat without adhesiveness as described for Pseudoplatystoma corruscans, Pseudopimelodus charus, R. quelen, and Pimelodus maculatus (Sato et al, 2003a). Non-hydrated eggs of L. alexandri measured on average 3.1 mm and after hydration this increased to 3.6 mm, an increase of approximately 16%, which can be considered small compared to eggs from other Siluriformes species (Sato et al, 2003b) and high compared to the egg diameter after hydration in the reared catfish Zungaro jahu (Nogueira et al, 2012).…”

“…Regarding the number of oocytes in relation to the weight of the ova, L. alexandri had an average of 74 oocytes g -1 , a value which is much smaller than other Siluriformes including Pseudoplatystoma corruscans (Sato et al, 2003a), Pimelodus maculatus (Sato et al, 1999), Z. jahu (Nogueira et al, 2012), T. galeatus (Santos et al, 2013), R. quelen, and Pseudopimelodus charus (Sampaio & Sato, 2006). The low fecundity (i.e., 324 oocytes per gram of ovulated ovary mass) was also described in another Siluriformes species that was induced to spawn: the endangered Steindachneridion parahybae from the Paraíba do Sul River, Brazil (Caneppele et al, 2009).…”

“…This has resulted in an increased effort to develop techniques for hatchery production of fish. The hypophysation has been used for induction and synchronization of ovulation and spawning in several species of fish in captivity (Woynarovich & Horvat, 1980;Sato et al, 1999;Sato et al, 2003a;Sampaio & Sato, 2006;Nogueira et al, 2012;Santos et al, 2013). Moreover, data on reproductive variables, such as fecundity and fertility, can be obtained from induced spawning; such variables are needed for species conservation and efficient production of embryos, larvae, and fingerlings.…”

Dynamics of ovarian maturation during the reproductive cycle of Metynnis maculatus, a reservoir invasive fish species (Teleostei: Characiformes)

“…In South American countries, carp pituitary extracts are the main source of hormones for the strip-spawning induction of rheophilic fish (Dias et al, 2012;Criscuolo-Urbinati et al, 2012;Felizardo et al, 2012;Hainfellner et al, 2012aHainfellner et al, , 2012bHonji et al, 2012;Nogueira et al, 2012;Weber et al, 2012). The native species of the South American continent are not exploited for this purpose, although it is an interesting way to add value to local fisheries and aquaculture by-products.…”

Ontogenetic development of Heterocharax macrolepisEigenmann (Ostariophysi: Characiformes: Characidae) with comments on the form of the yolk sac in the Heterocharacinae

“…The remaining information on freshwater Neotropical larval fishes are scattered in separate papers often dealing with a single or a few species. These include studies on clupeiforms (e.g., Severi & Verani, 2006;Silva et al, 2010), siluriforms (e.g., Chacon, 1975;Godinho et al, 1978;Oldani, 1983a;Kossowski & Madrid, 1991;Cardoso et al, 1995;Sanches et al, 1999;Luz et al, 2001;Godinho et al, 2003;Lundberg et al, 2004;Feiden et al, 2005;Marques et al, 2008;Oliveira et al, 2008;Amorim et al, 2009;Faustino et al, 2010;Perini et al, 2010;Rodrigues-Galdino et al, 2010;Buzollo et al, 2011;Fuller, 2012;Honji et al, 2012;Nogueira et al, 2012;Weber et al, 2012), gymnotiforms (e.g., Kirschbaum & Schugardt, 2002) and perciforms (e.g., Prokes et al, 1987;Pena et al, 1988;Nakatani et al, 1997;Korzelecka-Orkisz et al, 2012), besides the Characiformes. More specifically within the latter order, most studies have focused on representatives of the Anostomidae (Godinho et al, 2003), Curimatidae (Araújo Lima, 1991;Perini et al, 2013), Cynodontidae (Sousa & Severi, 2002), Erythrinidae (Matkovic & Pisanó, 1989;Gomes et al, 2007;Bialetzki et al, 2008;Maciel et al, 2009;…”