Morphological and morphometric aspects of early life stages of piabanha Brycon gouldingi (Characidae)

Abstract

Adult specimens of piabanha Brycon gouldingi were collected from Rio das Mortes (Mato Grosso, Brazil), adapted to captivity and induced to spawn at Buriti Fisheries (Nova Mutum, MT, Brazil). The early developmental stages of B. gouldingi were then characterized. Samples were collected at pre-determined times from oocyte extrusion to total yolk absorption. Oocyte diameter, total larval length (LT ) and yolk-sac volume were measured. The mean ± s.d. duration of embryo developmental of B. gouldingi was 13·90 ± 0·06 h at 26·40 ± 1·13° C. The mean ± s.d. oocyte diameter was 1·13 ± 0·06 mm with 54% of oocytes ranging from 1·11 to 1·20 mm. Seven stages characterized the early developmental phase of this species: zygote, cleavage, morula, blastula, gastrula, histogenesis-organogenesis and hatching, with unique features related to each stage. At hatching, the larvae measured 3·40 ± 0·07 mm, presented an elongated shape with yolk-sac volume of 0·46 ± 0·08 µl, non-pigmented eyes and exhibited swimming ability. When the yolk was completely absorbed at 55 h post-hatch, mean ± larval LT was 6·68 ± 0·65 mm, the eyes were highly pigmented and the teeth were visible. These are the first reported findings on the initial developmental stages of B. gouldingi and could be used to improve captive breeding management and conservation practices.

Embryonic development in Zungaro jahu

“…The start of the gastrula stage in Z. jahu was characterized by the epiboly movement, when the embryonic cells moved from the animal to the vegetative pole (Leme dos Santos & Azoubel, 1996). The phases of the epiboly movement are often characterized according to the percentage of yolk coverage, as previously reported by Buzzolo et al (2011) in Pimelodus maculatus and Faustino et al (2015) in B. gouldingi. In Z. jahu eggs, when approximately 50% of the yolk was covered, the most superficial cells began to move contrary to the epiboly movement (involution), originating two embryonic layers: epiblast and hypoblast.…”

“…The physical-chemical characteristics of the water from the incubators were: ammonia = 11.13 g/l, pH = 8.14, conductivity = 34 S/cm, dissolved oxygen = 7.26 mg/l, and alkalinity = 21 mg/l. The embryonic development of Z. jahu was divided into seven stages and classified according to Faustino et al (2011 and2015) into: zygote, cleavage, morula, blastula, gastrula, organogenesis, and hatching. The different stages and their corresponding characteristics are detailed in Table 1.…”

“…The end of the gastrula stage was characterized by the formation of the blastopore or vitelline plug, in agreement with the findings by Buzzolo et al (2011) in Pimelodus maculatus and Faustino et al (2011) in B. gouldingi. Organogenesis was defined by tissue and organ development. It began with the appearance of the embryonic axis, formed by the differentiation of the cephalic and caudal regions (Faustino et al, 2011(Faustino et al, , 2015. This was followed by the appearance of somites, which are muscle precursors that develop in blocks of transient cells and are necessary for segmental organisation of embryos (Gilbert, 2003).…”

Ultrastructure aspects of Brycon gouldingi (Teleostei, Characidae) related to swimming ability and feeding during larval development

“…Faustino et al . () provided basic knowledge of the morphology of early life stages of B. gouldingi and reported larval total length and yolk‐sac volume from the time of hatching to complete yolk absorption. This knowledge, combined with results of the present study, contributes to techniques for induced reproduction and larval rearing of this species.…”

Characterization of the initial ontogeny ofLeiarius marmoratus(GILL, 1870): larvae to juvenile

“…Despite the large number of freshwater teleost species currently known, few studies address ontogenetic aspects. Being the surveys more focused on evolutionary, ecological or descriptive aspects for several fish species from different watersheds (Andrade et al, ; Arashiro et al, ; Assega, Birindelli, Bialetzki, & Shibatta, ; Bialetzki et al, ; Costa & Neto, ; Faustino, Makino, Neumann, & Nakaghi, ; Gavaia, Dinis, & Cancela, ; Honji, Tolussi, Mello, Caneppele, & Moreira, ; Maciel, Júnior, Donzele, Lanna, & Menin, ; Miquelarena, Ortubay, & Cussac, ; Suzuki & Pompeu, ; Vrtílekv & Reichard, ; Zacardi, Silva, Bittencourt, Costa, & Nakayama, ). Thus, there is a gap regarding the ontogenetic aspects of these species, which is a fundamental knowledge as a support for taxonomic and fisheries biology studies.…”