Browsing by Author "Aristizábal, Eddie O."

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    Desarrollo embrionario de Pagrus pagrus bajo distintas condiciones de salinidad y temperaturas de incubación
    (Instituto Nacional de Investigación y Desarrollo Pesquero, 2016) Berrueta, M. Mercedes; Suárez, Julieta; Aristizábal, Eddie O.
    Pagrus pagrus is a demersal species widely distributed in the Mediterranean and the eastern and western shores of the Atlantic Ocean. In Argentina it distributes naturally along the coast of the Buenos Aires Province between 10 and 50 m depth. The estimate of egg quality during the early stages of embryonic development is a useful predictive criterion to evaluate the potential of the species to produce juveniles. The aim of this study was to describe in detail the stages of embryonic development and larval hatching time under different conditions of salinity and temperature. The fertilized eggs obtained from natural spawning were incubated at 15, 30 and 40 salinity levels combined with 14 and 18 °C temperature. In the different experiments the embryonic stages were photomicrographed and structures described. Egg development was completed in all experiments made. At 18 °C the fully formed embryo hatched at 40 h postfertilization; at 14 °C hatching occurred 73 h after. The effect of salinity on embryonic development was reflected in an irregular growth of blastomeres during the cleavage stages at 15 and 40 salinity with a subsequent abnormal development of the caudal region in larvae incubated at said levels. Knowing the embryonic stages, sequence of segmentation, time of organ formation and duration of embryonic development until hatching is a basic requirement to evaluate the quality of egg batches devoted to mass larvae production.
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    Desove en cautiverio y calidad de los huevos y larvas del besugo, Pagrus pagrus (L.)
    (Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), 2006) Aristizábal, Eddie O.
    Spontaneous spawning of red porgy was achieved in captivity by using photoperiod and temperature control systems along the year. During a four-month reproduction period females released in average about 0.2 times their own body weight in oocytes with an energy content of 5.71 J mg-1 wet weight. A total of 28.8 x 106 eggs and approximately 200 g of viable eggs (wet weight) per female kg were obtained. The eggs and larvae quality in terms of hatching and larval survival rates experienced a significant variation during the spawning season ranging between 0%-92% and 0.3%-33.2% respectively. Comments in reference to the probable causes of these variations and the need of carrying on with this line of research are presented.