Browsing Artículos científicos by Issue Date
Now showing items 21-40 of 330
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Fenología y desarrollo de las agallas de las ramas del güisaro (Psidium guineense Swartz) (Myrtaceae) y su relación con varias especies de Microhimenopteros en Heredia, Costa Rica.
(Universidad Nacional, Costa Rica, 1991-01-01)En una población natural de güísaro (Psidium guineense), en Barva de Heredia, se estudió el desarrollo de las agallas de las ramas y la fenología de cuatro especies de micro himenópteros emergidos de ellas, desde abril de ... -
Growth performance of Colossoma macropomum (Cuvier) juveniles at different feed rations
(Wiley & Sons, 1992)Growth performance, feed utilization and changes in body composition of Colossoma macropomum (Cuvier) juveniles — in the weight range 2 to 200 g — fed an artificial high protein diet, have been analysed against feed ... -
Utilización de variables morfometricas para explicar el comportamiento del peso fresco y eviscerado en tres especies de peces del género opisthonema. (Pisces: Clupeidae)
(Universidad Nacional, Costa Rica, 1992-01-01)Se trabajó en la búsqueda del mejor modelo estadístico que explique el peso fresco y eviscerado, utilizando las variables morfométricas más sobresalientes. Mediante el análisis de varianza, se comprobó que hay diferencia ... -
Preliminary evaluation of eyestalk ablation and thoracic ganglion importation on spermatophore quality and molting of male Penaeus vannamei
(Universidad Nacional, Costa Rica, 1992-01-01)Males of Penaeus vannamei (mean weight = 25.05 ± 1.89 g), selected from a commercial semi-intensive pond, selected form a commercial semi-intensive pond, were used to study the effect of thoracic ganglion implantation on ... -
The effect of high rearing densities on the growth of juveniles of the cichlid, cichlasoma managuense
(Universidad Nacional, Costa Rica, 1992-01-01)The effect of high density culture on the growth of juvenile jaguar cichlids was investigated. Mean growth rate decreased with density, while the growth rate of the largest fishes was not affected. Reduction in mean growth ... -
Growth of Jaguar Cichlid (Cichlasoma managuense) juveniles at different oxygen levels
(Universidad Nacional, Costa Rica, 1992-01-01)The dependence of growth on the dissolved oxygen level was analyzed un juveniles of the guapote tigre, Cichlasoma managuense, in a recirculated system. The guapote tigre is relatively tolerant to low oxygen levels, averaging ... -
Development and Deterioration of Spermatophores in Pond-Reared Penaeus vannamei
(World aquaculture society, 1993)Spermatophore deterioration in pond-reared Penaeus vannamei was studied, and spermatophore quality was evaluated and improved. Sperm production of males collected from grow-out ponds was increased by two techniques: ... -
Larvae of the Costa Rican Hetaerina (Odonata: Calopterygidae) with comments on distribution
(Royal Entomological Society, 1993)The larvae of seven of the nine Costa Rican species of Hetaerina (H.capitalis, H.cruentata, H. fuscogutfata, H. majuscula, H. miniata, H. occisa and H. titia) were identified by matching their Cellulose Acetate Gel ... -
Interaction of bacteria and male reproductive system blackening disease of captive Penaeus setiferus
(Elsevier, 1993)The genital apparatus of male penaeid shrimp, Penaeus sett’ferus, blackens with resulting detrimen tal effects ton mating for production of larvae when animals are kept in controlled maturation/repro duction situations. A ... -
Biometry of Modiolus capax (Bivalvia: Mytilidae) in Playa Ocotal, Guanacaste, Costa Rica
(Universidad de Costa Rica, 1994)155 specirnens of mussels (Modiolus capax) were gathered during March 1993 in a subtidal hed, located in northern Ocotal, Guanacaste, Costa Rica. For each individual in the randon sample, shell length, breadth and height ... -
Effects of the protein: energy ratio in isocaloric diets on the growth of Cichlasoma managuense (Gunther 1869)
(Wiley & Sons, 1994)A feeding experiment was conducted to evaluate the growth of tiger guapote, Cichlasoma managuense (Gunther), fed on isocaloric diets with varying proteinxnergy ratios. The relative metabolic growth rate increased with ... -
Environmental impacts of nitrification and nitrate adsorption in fertilized andisols in the Valle Central of Costa Rica
(Williams & Wilkins, 1994)A major scientific challenge for modern agriculture is control of off-site effects on the water resource. In the Valle Central of Costa Rica, coffee plantations may leach fertilizer-derived (Equation presented) to groundwaters, ... -
Annotated checklist of marine molluscs collected during the R. V. Victor Hensen Costa Rica Expedition 1993/1994
(Universidad de Costa Rica, 1995)An annotated checklist of species of marine molluscs from Golfo Dulce, Bahfa Coronado and Golfo de Nicoya. Costa Rica, obtained aI 20-200 m during the Victor Hensen cruise, includes 157 species: 108 Gastropoda and 49 ... -
Las especies de Trachelomonas (Algas: Euglenophyta) en tres lagunas volcánicas de Costa Rica
(Universidad de Costa Rica, 1995)The algae of three lakes of volcanic origin, Laguna Hule, Congo and Bosque Alegre (740 m. above see leve!) were studied frorn 1989 to 1993. Five Trachelomonas (Euglenophyta ) species and sorne of their varieties are ... -
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 ... -
Tamaños y proporción sexual de Ucides occidentalis (Crustacea: Gecarcinidae) en un manglar de Costa Rica
(Universidad Nacional (Costa Rica), 1995-02-22)Sizes and sex ratios of Ucides occidentalis (ORT-MANN 1897) were studied in the mangrove area of Estero Panama, Guanacaste, Costa Rica, from March to August 1982. The caparace length was 36.7-84.5 mm for males and 36.00-60.8 ... -
Lista agregada de peces en tres zonas de manglar del golfo de Nicoya, Costa Rica
(Universidad Nacional (Costa Rica), 1995-02-22)El conocimiento en nuestro país sobre la ictiofauna asociada a zonas de manglar es escaso, especialmente en zonas alejadas de la parte central del Golfo. La suma de características físicas y biológicas que se dan en estas ... -
Batch fertility and larval parameters of the jaguar cichlid (Cichlasoma managuense) spawned in the laboratory
(Universidad Nacional (Costa Rica), 1995-05-06)Abstract: Batch fertility and larval parameters of 32 spawns of the jaguar guapote (Cichlasoma managuense) in the laboratory were analyzed. Batch fertility was positively correlated with the female weight with spawns between ... -
Análisis de las referencias sobre acuicultura en Costa Rica 1970-1994
(Universidad Nacional (Costa Rica), 1995-05-25)Se recopiló un total de 360 publicaciones realizadas en Costa Rica en el área de Acuicultura entre 1970 y 1994. Se clasifican y analizan estas referencias según tipo de publicación, temática general, fecha de publicación, ... -
The growth of juvenile jaguar guapote (Cichlasoma managuense) fed diets with different carbohydrate levels
(Universidad Nacional (Costa Rica), 1995-06-27)Se evaluó el crecimiento de juveniles del guapote tigre (Cichlasoma managuense) alimentado con dietas isocalóricas conteniendo niveles de carbohidrato del 11 al 36 por ciento. El experimento se realizó en un sistema de ...
