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Santos,Hélio Batista dos; Sampaio,Edson Vieira; Arantes,Fábio Pereira; Sato,Yoshimi. |
Lophiosilurus alexandri is an endemic fish from the São Francisco River basin, Brazil. The aim of this study was to induce L. alexandri to spawn and to obtain data on several reproductive variables for this species. For induced spawning, adults were submitted to Cyprinus carpio pituitary homogenate (CPH). Nine of the 12 females (75%) responded positively to the treatment. The stripping of oocytes was performed 8.4 h after the second dose of CPH with the water temperature maintained at 26ºC. The number of stripped oocytes per gram of ova was 74 ± 5 oocytes g-1, and the mean oocyte diameter was 3.1 ± 0.2 and 3.6 ± 0.2 mm, before and after hydration, respectively. The oocytes were opaque, yellowish, demersal, highly adhesive, and covered by a gelatinous coat.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Artificial reproduction; Fecundity; Fertility; Hypophysation assay; Neotropical catfish. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000300607 |
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Nogueira,Lorena B.; Azevedo,Pedro G.; Canelhas,Mônica R.; Bedore,Alessandra G.; Lopes,João M.; Godinho,Hugo P.. |
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... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Early ontogenesis; Growth; Morphological development; Neotropical catfish. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000100009 |
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