Patagonian toothfish (Dissostichus eleginoides) is a hefty notothenioid fish and a key species within the marine ecosystem with a high migratory capacity across sub-Antarctic and south American Pacific oceans. Transcriptome characterization and molecular markers associated with micro and macro-evolutionary studies are not available, which in turn limits the gain of knowledge about the genetic basis of this species. Therefore, in the present study, a de novo transcriptome from eight tissue and an embryonic state of Patagonian toothfish was developed, using the Illumina Hiseq 4000 platform. A total of 233,424 superTranscripts were assembled and 37,446 annotated against public databases. Moreover, we identified 71,107 expressed sequence tag-simple sequence repeats (EST-SSRs), with an average number of 0.3 SSRs per superTranscripts and one SSR per 1.12 kB. The most abundant SSR type was repeated dinucleotide (53.67%), followed by trinucleotide (13.73%) repeats. From the total of EST-SSRs identified, 34,196 primer pairs were properly designed and a subset of 25 immune loci were selected for its evaluation as potential EST-SSR population markers. Of this subset, 11 proved to have good technical features and were evaluated in 64 animals from four Patagonian toothfish populations. A number of 63 alleles were identified, with a mean of 4.9 alleles per locus and a polymorphism information content ranging from 0.224 to 0.591, with a mean of 0.50. Significant (F ST , range 0.082-0.117 and G ST , range 0.069-0.291) genetic differentiation (P < 0.05) was determined among the populations analyzed. Therefore, the results presented here represent a relevant genetic resource for biological studies on evolution, conservation, genetic diversity, population structure, and genetic management of breeding stocks of this important species.

RESUMEN.Se reportan resultados en la captura, transporte y mantención de ejemplares vivos de bacalao de profundidad (Dissostichus eleginoides Smitt, 1898), para conformar un plantel de reproductores, destinados a emprender el cultivo experimental de este importante pez marino. Se enfatiza las causas de mortalidad y tasas de sobrevivencia post-captura en el mar. En tres años de experiencia se obtuvo una sobrevivencia general de 13% en promedio, de tres campañas de captura, y un período de tres años de mantención de los peces en estanques de 30 m 3 en tierra, en un sistema de agua de mar circulante con control de factores ambientales. La mortalidad en los tanques ocurrió principalmente en el periodo inicial hasta lograr la adaptación en el hábitat artificial. Palabras clave: Dissostichus eleginoides, bacalao de profundidad, captura, transporte vivos, sobrevivencia en tanques, Chile. Capture and maintenance of Dissostichus eleginoides to establish a broodstock groupABSTRACT. We report results in the capture, transport and maintenance of live toothfish (Dissostichus eleginoides Smitt, 1898), to form a broodstock, for undertaking the experimental cultivation of this valuable marine fish. Emphasis is made in the causes of mortality and survival rates post capture at sea. In three years of experience was obtained an overall survival of 13% on the average, in three campaigns of capture, and a three-year maintenance of fish in 30 m 3 ponds on land, in an environmental factors controlled circulating seawater system. The tanks mortality occurred mainly in the initial period to achieve adaptation in artificial habitats.

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Resumen.-El desarrollo embrionario y larval de Dissostichus eleginoides es descrito por primera vez utilizando ejemplares cultivados en laboratorio (4 a 8°C). Periódicamente fueron fijados huevos y larvas para describir el desarrollo. Los huevos midieron de 3,1 a 3,5 mm de diámetro, esféricos, de corion transparente y superficie levemente rugosa, con 28 gotas oleosas, ubicadas en torno al polo germinativo y tardaron 30 a 33 días en eclosionar. Las larvas consumieron el saco vitelino en 18 días (larvas vitelogénicas, 8-13 mm), luego comienzan a desarrollarse los rayos de las aletas, se incrementa la pigmentación y se distinguen 3 zonas con agregación de melanóforos (parte posterodorsal de la cabeza, sobre el intestino y delante del pedúnculo caudal). El complejo hipural a estuvo completamente formado cuando las larvas midieron entre 49 y 53 mm (LS), lo que ocurrió a 57 días de la eclosión. Palabras clave: Dissostichus eleginoides, desarrollo embrionario y larvalAbstract.-This is the first description of the embryonic and early larval development of laboratory-reared (4-8°C) Dissostichus eleginoides. Specimens were periodically sampled to describe egg and larval development. Eggs were spherical (3.1-3.5 mm diameter) and had a transparent chorion and slightly rough surface, with 28 oil globules located around the germinal pole. Eggs incubated between 30 and 33 days until hatching. At day 18 post-hatching, the yolk sac was absorbed by vitellogenic larvae (8-13 mm total length), after which, the fin rays started to develop, pigmentation increased, and main melanophore aggregation zones were distinguished on the posterodorsal part of the head, the intestine, and before the caudal peduncle. The hypural complex was fully formed by day 57 post-hatching (49-53 mm standard length).

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