doctoralThesis
Prospecção de marcadores citogenéticos em grandes peixes pelágicos marinhos
Fecha
2017-05-12Registro en:
SOARES, Rodrigo Xavier. Prospecção de marcadores citogenéticos em grandes peixes pelágicos marinhos. 2017. 113f. Tese (Doutorado em Biotecnologia) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2017.
Autor
Soares, Rodrigo Xavier
Resumen
The big pelagic fish represents one of the most lucrative subjects of the industrial fisheries in Brazil. The Rio Grande do Norte by the privileged geographic position constitutes nowadays one of the regions in which the commercial oceanic fishing is more productive and tends to expand with new policies of governmental incentive.Different from other World’s producer regions that are researching the main exploited species, in Brazil the studies that objectify the population delimitation and to list data for the conservation of the species are scarce. Among the pelagic groups is common to observe a predominance of a minor diversity in relation to the abundance, this is a characteristic in two of the most important families of this oceanic region, Sphyraenidae (barracudas), Carangidae (jacks and pompanos) and Coryphaenidae (dolphinfish) and Istiophoridae (marlins). Data about these species are surrounded of logistics difficulties for its size, capture way and habitat which occupies. The first cytogenetical informations for some species of this family were obtained only recently. Here is presented a cytogenetical study with 9 pelagic fish species from the Atlantic, of the families Sphyraenidae, Carangidae, Corypahenidae, Istiophoridae and Megalopidae and 1 Indo-Pacific Carangidae. The results revealed numerical divergences and in the karyotipical macrostructure contrasting with the pattern considered basal for the Teleosts, besides the existence of masculine heterogamety, through a system of multiple sexual chromosomes of the kind X1X1X2X2/X1X2Y. Using techniques such as AgNORs, MM/DAPI it was possible to identify single ribosomal sites and showed cytotaxonomic markers for all. It was also applied more resolutive cytogenetic techniques based on multigenic sequences mapping through FISH (Fluorescence in situ Hybridization) enabled for the first time for some of these families to infer about the active karyoevolutive processes and evolutive aspects of the investigated species. Through the developed techniques it will be also possible to expand the knowledge about this important marine resource,subsidizing future policies of the management of stocks, as well as future support for the technological development of marine aquaculture.