%0 Journal Article
%T Induced spawning and early ontogeny in hatchery-reared catfish Zungaro jahu (Siluriformes: Pimelodidae)
%A Nogueira
%A Lorena B.
%A Azevedo
%A Pedro G.
%A Canelhas
%A M£¿nica R.
%A Bedore
%A Alessandra G.
%A Lopes
%A Jo£¿o M.
%A Godinho
%A Hugo P.
%J Neotropical Ichthyology
%D 2012
%I Sociedade Brasileira de Ictiologia
%R 10.1590/S1679-62252012000100009
%X hatchery-kept catfish jahus zungaro jahu (ihering, 1898) were induced to spawn with carp pituitary extract. the telolecithal eggs were round (1.6 ¡À 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 ¡À 144. hatching occurred 14.5 h after fertilization, at a temperature of 27.3 ¡À 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 ¡À 0.1 mm tl), the retina was pigmented, the mouth opened and dorsoflexion of the notochord had initiated. at 36 hph (6.4 ¡À 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 ¡À 0.2 mm tl). at 128 hph (8.6 ¡À 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 ¡À 2.5 mm tl), the metamorphosis was completed and the larvae had acquired the juvenile appearance.
%K early ontogenesis
%K growth
%K morphological development
%K neotropical catfish.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S1679-62252012000100009&lng=en&nrm=iso&tlng=en