Browsing Artículos científicos by Issue Date
Now showing items 1-20 of 80
-
A dynamic simulation model for the blooming of Oscillatoria agardhii in a monomictic lake
(Elsevier, 1995-01-15)The occurrence of phytoplankton blooms is a common problem in water bodies. The quantitative description of the algal population growth is of primary importance to understand the mechanisms which lead to these phytoplankton ... -
Efecto de la fitasa en el aprovechamiento del fósforo en dietas para tilapia (Oreochromis niloticus). Resultados preliminares.
(UNICIENCIA, 2001-06-01)Con el fin de evaluar si mediante la adición de la enzima fitasa se puede aumentar la cantidad de fósforo (P) disponible en dietas comerciales de tilapia (Oreochromis niloticus) y con ello reducir su excreción al medio, ... -
Organic matter sedimentation and resuspension in tilapia (Oreochromis niloticus) ponds during a production cycle
(2002-07-01)The rates of sedimentation and resuspension of organic carbon and total nitrogen were measured in earthen fishponds, based on nutrient input, water quality parameters and fish size and biomass. Material collected in ... -
Conceptualization and validation of a dynamic model for the simulation of nitrogen transformations and fluxes in fish ponds
(Elsevier, 2002-11-01)Nitrogen is a key element in aquatic environments and an important pond management variable. In aquaculture systems, nitrogen accumulation eventually leads to a deterioration of the system. The interactions between various ... -
Distribución y abundancia de Caiman crocodilus en el Refugio Nacional de Vida Silvestre Caño Negro, Costa Rica
(Revista de Biología Tropical vol.51 no.2 571-578 2003, 2003)The distribution and abundance of a population of Caiman crocodilus fuscus were estimated by monthly counting of eyeshines at night, from February 1999 to March 2000 in six transects of Río Frío in the Caño Negro National ... -
Growth of Oreochromis aureus fed with diets containing graded levels of coffee pulp and reared in two culture systems
(Aquaculture vol.217 no.1-4 275-283 2003, 2003)A study was conducted to compare growth and feed utilization of Oreochromis aureus fed graded levels of coffee pulp (CoP) and reared in aquaria or in pens. Diets contained 0, 130, 260 and 390 g kg 1 of oven-dried CoP. ... -
Induction of sperm activation in open and closed thelycum penaeoid shrimps
(Aquaculture vol.216 no.1-4 371-381 2003, 2003)A modified egg water (EW) technique for in vitro induction of sperm activation was applied to Trachypenaeus byrdi, Xiphopenaeus riveti (closed thelycum shrimps), and Litopenaeus occidentalis (open thelycum) from a tropical ... -
Extensive blooms due to Cochlodinium polykrikoides: New to Costa Rica
(Intergovernmental Oceanographic Commision, UNESCO, 2004-10-01)At the beginning of April of 2004 an extensive bloom produced by Cochlodinium polykrikoides was detected, embracing the whole Pacific coast of Costa Rica. The bloom was characterized by a red-oxide colour and was located ... -
Efecto del probiótico Bacillus subtilis sobre el crecimiento y alimentación de tilapia (Oreochromis niloticus) y langostino (Macrobrachium rosenbergii) en laboratorio
(Revista de Biología Tropical, 2004-12-01)Three experiments were conducted to analyze the effect of the probiotic Bacillus subtilis on the growth of juvenile tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii). The experiments were ... -
Nitrogen budget and fluxes in Colossoma macropomum ponds
(Blackwell Publishing Ltd., 2005-07-01)This study quanti¢ed the accumulation of nitrogen (N) in the water column, sediments, ¢sh and seepage water during a production cycle of Colossoma macropomum. By combining estimates of the deposition rates of uneaten feed, ... -
Effect of organic nitrogen and carbon mineralization on sediment organic matter accumulation in fish ponds
(Aquaculture Research, 2005-07-01)In aquaculture, ponds with high loads of organic inputs, organic matter accumulates at the bottom over time. Uneaten feed, senescent phytoplankton and faeces are the principal sources of accumulated material, but quanti¢cations ... -
Occurrence and predominance of the fish killer Cochlodinium polykrikoides on the Pacific coast of Costa Rica
(2006-07-01)Water samples were collected at several points along the Pacific coast of Costa Rica (10°00’N, 84°15’E) fortnightly from January 2003 to June 2004. During this period, dense red-ochre discolourations dominated by Cochlodinium ... -
Rose snapper marine culture in Costa Rica
(Panorama Acuícula Magazine, 2008-03-01)A great variety of species of snappers are cultivated in Asia, and others recently studied in Mexico, Australia and the United States. In Costa Rica, the Marine Park of the Pacific has increased the production of juveniles ... -
Thoracic nerve cord - ganglia recognition in intraspecific and interspecific transplants in the white shrimp, Penaeus (Litopenaeus) vannamei
(Science Direct, 2009-03)The recognition response of Penaeus (Litopenaeus) vannamei against thoracic nerve cord–ganglia transplants from three species of Penaeidae: P. vannamei, P. (Litopenaeus) stylirostris, and Trachypenaeus byrdi, and one species ... -
Spotted rose snapper (Lutjanus guttatus) aquaculture research and development as socio-economic alternative for Costa Rican fishing communities
(2010-06-01)The spotted rose snapper (Lutjanus guttatus) is one of the main target coastal species, but landings are decreasing in quantity and size. Reports include a mean capture size of 50 cm with gill nets and 38 cm with bottom ... -
Characteristics of the spontaneous deposition of Sn in polycrystalline Pt
(2012-04)Spontaneous deposition of tin (Sn) in polycrystalline platinum (Pt pc) from a sulfuric acid solution of tin salts, was evaluated by conventional electrochemical techniques, to determine its characteristics. Tin was deposited ... -
The histological structure of the androgenic gland and cellular cord of the male reproductive system of adult litopenaeus and rimapenaeus byrdi
(2012-05-01)The current knowledge of the precise extension and location of the androgenic gland (AG) in the genera Litopenaeus and Rimapenaeus is partial. Therefore, we analyzed the complete structure of the AG and cellular cord ... -
Observation of Varroa destructor behavior in capped worker brood of Africanized honey bees
(Springer Science + Business Media B.V., 2012-06-12)The behavioral activity of Varroa destructor was observed using transparent cells. Mite oviposition started at 45.0 ± 25.0 h post capping, followed by the next eggs laid at regular 27.3 ± 2.0 h intervals. On the prepupa, ... -
First record of the sea anemone Anthopleura nigrescens (Cnidaria: Actiniaria: Actiniidae) on the Pacific coast of Central America
(Marine Biological Association of the United Kingdom, 2012-08)We report the first record of the sea anemone Anthopleura nigrescens on the Pacific coast of Central America. Five specimens from Mata Limón (Costa Rica) were collected from rocks of a man-made breakwater at sub-tidal ... -
Unexplored Character Diversity in Onychophora (Velvet Worms): A Comparative Study of Three Peripatid Species
(Sars International Centre for Marine Molecular Biology, Norway, 2012-12-17)Low character variation among onychophoran species has been an obstacle for taxonomic and phylogenetic studies in the past, however we have identified a number of new and informative characters using morphological, molecular, ...