Ingestion, Absorption and Assimilation Efficiencies, and Production in the Sea Urchin Arbacia dufresnii Fed a Formulated Feed

Sea urchins have been used as a source of food from prehistoric times and as a research animal model since the 19th century. They presently are harvested in many parts of the world. In Argentina, sea urchins have been studied only from biological perspectives. Of the 14 species of sea urchins found off the coast of Argentina, Arbacia dufresnii is the most abundant. It is an omnivorous species that exists in dense populations in Nuevo Gulf. Biomass production in sea urchins, especially gonad yield, is related to food quantity and quality. In the field, A. dufresnii has a small size and low gonad biomass and gamete production. Therefore to test the hypothesis that a high-quality formulated food would produce more biomass and gonad yield than that found in the sea urchins from a natural population, sea urchins were reared in a laboratory aquaculture system for 8 wk in autumn when gametogenesis occurs. In April, 30 sea urchins were collected and dissected to establish the initial condition (Baseline). Another 32 sea urchins were collected in April and maintained until June in aquaria at constant temperature and salinity and fed a formulated feed (Fed). At the conclusion of the experiment, 30 sea urchins were collected from the field population in June (Field) to establish the population condition in the Field and for comparison with the Fed sea urchins. Fed sea urchins had a 20% greater gain in weight resulting from an increase in both somatic and gonadal tissue beyond that of the field population. All organs increased in weight in females and all organs except the lantern in males. The absorption efficiency in Fed sea urchins was over 80%. Fed sea urchin had organic biomass production higher than Field sea urchins. Differences were found in the gonad cellular composition: Fed females had a unimodal oocyte size-frequency distribution, in contrast to a multimodal distribution in Field females. Fed males had fewer mature gametes than Field males. Both testes and ovaries had more nutritive phagocytes in Fed sea urchins than in Field sea urchins. Proximate composition of gonads, however, was similar in Fed and Field sea urchins. Fed individuals showed a remarkable increase in biomass production. The biochemical and cellular composition of the gonads reflected this. This indicates that A. dufresnii fed a highly nutritional food is able to assimilate nutrients with high efficiency and produce an increased gonad yield.Fil: Rubilar Panasiuk, Cynthia Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Epherra, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; ArgentinaFil: Deias Spreng, Julia. Universidad Nacional de la Patagonia; ArgentinaFil: Díaz de Vivar, María Enriqueta Adela. Universidad Nacional de la Patagonia; ArgentinaFil: Avaro, Marisa Gladis. Universidad Nacional de la Patagonia; ArgentinaFil: Lawrence, Addison L.. Texas A&M University System; Estados UnidosFil: Lawrence, John M.. University of South Florida; Estados Unido

Latin America Echinoderm Biodiversity and Biogeography: Patterns and Affinities

We investigated the current patterns of diversity by country and by class of echinoderms, and analyzed their biogeographical, depth, and habitat or substratum affinities, using the database of the appendix of this book. Traditionally, the area has been divided into five biogeographical Regions and nine Provinces that cover a wide climate range. Currently, the echinoderm fauna of Latin America and Canary islands is constituted by 1,539 species, with 82 species of Crinoidea, 392 species of Asteroidea, 521 species of Ophiuroidea, 242 species of Echinoidea and 302 species of Holothuroidea. Species richness is highly variable among the different countries. The number of species for the countries is highly dependent on its coast length. The echinoderm fauna of the Panamic, Galápagos and the Chilean regions are biogeographically related. Other regions that are closely related are the Caribbean, West Indian, Lusitania and Brazilian. Cosmopolitan species are an important component in all the regions. Affinities between faunas are a consequence of the combination of climatic and trophic factors, connectivity as a function of distance, currents patterns and historical processes. Moreover, different environmental factors would be responsible for the faunal composition and species distribution at different spatial scales. The bathymetrical distribution of the echinoderm classes and the species richness varies according to the depth range and the ocean. Most species occurred at depths between 20 and 200 m. The Caribbean-Atlantic regions are richest in shallow depths, while the Pacific coast has higher values in deeper waters. The domination of each class in each substrate and habitat categories also varies differentially along each coast.Fil: Pérez Ruzafa, Ángel. Universidad de La Laguna; EspañaFil: Alvarado, Juan José. Universidad de Costa Rica. Centro de Investigación en Ciencias del Mar y Limnología; Costa RicaFil: Solís Marín, F. A.. Universidad Nacional Autónoma de México; MéxicoFil: Hernández, José Carlos. Universidad de La Laguna; EspañaFil: Morata, Alex. Universidad de La Laguna; EspañaFil: Marcos, C.. Universidad de La Laguna; EspañaFil: Abreu Pérez, M.. Ministerio de Ciencia, Tecnología y Medio Ambiente.; CubaFil: Aguilera, Orangel. Museu Paraense Emilio Goeldi; BrasilFil: Alió, J.. Instituto Nacional de Investigaciones Agrícolas; VenezuelaFil: Bacallado Aránega, J. J.. Muso de la Naturaleza y El Hombre de Tenerife; EspañaFil: Barraza, E. Tomás. Ministerio de Medio Ambiente y Recursos Naturales; El SalvadorFil: Benavides Serrato, M.. Instituto de Investigaciones Marinas y Costeras; ColombiaFil: Benítez Villalobos, F.. Universidad del Mar; MéxicoFil: Betancourt Fernández, L.. Programa Ecomar, Inc; República DominicanaFil: Borges, Margarida. Universidade Estadual de Campinas; BrasilFil: Brandt, M.. University Brown; Estados UnidosFil: Brogger, Martin Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Borrero Pérez, G. H.. Instituto de Investigaciones Marinas y Costeras; ColombiaFil: Buitrón Sánchez, B. E.. Universidad Nacional Autónoma de México; MéxicoFil: Campos, L. S.. Universidade Federal do Rio de Janeiro; BrasilFil: Cantera, J. R.. Universidad del Valle; ColombiaFil: Clemente, Sabrina. Universidad de La Laguna; EspañaFil: Cohen Renfijo, M.. Universite de la Mediterranee; FranciaFil: Coppard, S. E.. Smithsonian Tropical Researchh Institute; PanamáFil: Costa Lotufo, L. V.. Universidade Federal do Rio de Janeiro; BrasilFil: Guanuco de García, María del Valle. Ministerio de Ciencia, Tecnología y Medio Ambiente.; CubaFil: Díaz de Vivar, María Enriqueta Adela. Universidad Nacional de la Patagonia. Facultad de Ciencias Naturales. Sede Puerto Madryn; ArgentinaFil: Díaz Martinez, J. P.. Universidad del Mar; MéxicoFil: Díaz, Yudiesky Cancio. Universidad Simón Bolívar; VenezuelaFil: Durán González, A.. Universidad Nacional Autónoma de México; MéxicoFil: Epherra, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Rubilar Panasiuk, Cynthia Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Pérez, Analía Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentin

Latin America echinoderm biodiversity and biogeography: Patterns and affinities

We investigated the current patterns of diversity by country and by class of echinoderms, and analyzed their biogeographical, depth, and habitat or substratum affinities, using the database of the appendix of this book. Traditionally, the area has been divided into five biogeographical Regions and nine Provinces that cover a wide climate range. Currently, the echinoderm fauna of Latin America and Canary islands is constituted by 1,539 species, with 82 species of Crinoidea, 392 species of Asteroidea, 521 species of Ophiuroidea, 242 species of Echinoidea and 302 species of Holothuroidea. Species richness is highly variable among the different countries. The number of species for the countries is highly dependent on its coast length. The echinoderm fauna of the Panamic, Galápagos and the Chilean regions are biogeographically related. Other regions that are closely related are the Caribbean, West Indian, Lusitania and Brazilian. Cosmopolitan species are an important component in all the regions. Affinities between faunas are a consequence of the combination of climatic and trophic factors, connectivity as a function of distance, currents patterns and historical processes. Moreover, different environmental factors would be responsible for the faunal composition and species distribution at different spatial scales. The bathymetrical distribution of the echinoderm classes and the species richness varies according to the depth range and the ocean. Most species occurred at depths between 20 and 200 m. The Caribbean-Atlantic regions are richest in shallow depths, while the Pacific coast has higher values in deeper waters. The domination of each class in each substrate and habitat categories also varies differentially along each coast.54251