Culture of L. vannamei marine shrimp is very important to Venezuelan aquaculture. Until 2005, Venezuelan production by hectare was one of the highest in Latin America. Part of the industry success was built upon domestication of the species and selection of favorable traits and to work under closed cycle conditions, which have led to the possibility to stay free -for more than two decades- of severe viral diseases such as Taura and White Spot virus. However, by 2005 Taura virus was confirmed affecting a total of 67% farms in Zulia, Falcon and Nueva Esparta States. Epidemic diseases have lead to farmers to look for new alternatives, one of which is the culture of marine shrimp in inland low-salinity water. The aim of this present study was to culture L. vannamei marine shrimp in inland low-salinity water in Paraguana, Falcon State, Venezuela. Postlarvae at PL12 stage, were cultured in a 969 m2 pond. Before culturing, samples of water and soils were analyzed to accomplish recommended culture parameters for L. vannamei in low-salinity conditions. Postlarvae studied came from a genetic program and were acclimated by reducing salinity to 4 ppm through 58.5 hours. Once acclimation was reached, postlarvae were stocked at a density of 42 PLs/m2. Physical and chemical parameters were registered during culture (dissolved oxygen, salinity and temperature). A pellet dry-diet K-maron 35 (R) was given as diet. Survival percentage, average weight, growth rate (g/week), total average length, feed conversion rate and productivity were evaluated through monthly sampling. Data were analyzed through descriptive statistics. L. vannamei marine shrimp was cultured during 94 days and the following production data was registered: 65.19% survival, 10.66 gr. average weight, feed conversion factor of 1.01:1 and a productivity level of 2,579.98 kg/ha/cycle. Results show this type of culture is highly feasible and it might become a new alternative for the small-medium local agriculture producers of Paraguana-Falcon, Venezuela.

El cultivo del camarón marino Litopenaeus vannamei (Boone, 1931) es el rubro más importante de la acuicultura venezolana. Hasta el año 2005, su producción por hectárea en Venezuela era una de las más altas en Latinoamérica. El éxito residía en parte, en la domesticación de la especie y el haber cerrado el ciclo biológico, lo cual le permitió al país mantenerse por más de dos décadas, libre de las enfermedades virales de impacto severo como Taura y Mancha Blanca. Sin embargo, en el año 2005 se confirmó la presencia del virus del Taura, que afectó un 67% del total de granjas en los estados Zulia, Falcón y Nueva Esparta. Las enfermedades han motivado a los camaronicultores a buscar alternativas, dentro de las cuales se encuentra el cultivo de camarón marino en agua dulce. Por esta razón, este trabajo tuvo como objetivo el cultivo de camarón (L. vannamei) en agua dulce en Paraguaná, estado Falcón, Venezuela. Las postlarvas (Pls), fueron sembradas en un estanque de 969 m2 de superficie. Antes de iniciar el ciclo de cultivo, se analizaron muestras de agua y de los suelos para garantizar que los parámetros recomendados para el cultivo de L. vannamei en agua dulce se cumplieran. Las Pls provenientes de un programa de mejoramiento genético fueron sometidas a un período de aclimatación y adaptación al agua dulce durante 58,5 horas. Obtenida la aclimatación se procedió a la siembra de las mismas a una densidad de 42 Pls/m2. Durante el cultivo se registraron los parámetros físico-químicos (oxígeno disuelto, salinidad y temperatura). La dieta de los camarones consistió en un alimento balanceado peletizado K-maron 35®. El porcentaje de supervivencia, peso promedio, crecimiento semanal promedio, talla promedio, factor de conversión alimenticia y productividad se registraron mediante muestreos mensuales. Para el análisis de datos se empleó estadística descriptiva. El cultivo tuvo una duración de 94 días y se registraron los siguientes valores de producción: 65,19% de supervivencia, 10,66g. de peso promedio, 1,01:1 de factor de conversión alimenticia y un rendimiento de 2.579,98 kg/ha/ciclo. Los resultados demuestran la factibilidad de este tipo de cultivo como una nueva alternativa de producción acuícola para los pequeños-medianos productores en la Península de Paraguaná-Falcón, Venezuela.

Las multiples variaciones que existen en cuanto a los diferentes aspectos de biometria, genetica, bioquimica, fisiologia y nutricion de las distintas poblaciones de Artemia, han hecho dificil una correcta clasificacion taxonomica. El objetivo de este trabajo fue la caracterizacion morfometrica de adultos de Artemia de dos poblaciones venezolanas: Las Cumaraguas-Falcon y Coche-Nueva Esparta a traves de 12 caracteres morfometricos y establecer su relacion con poblaciones americanas procedentes de Colombia, Chile, Peru, Argentina y Estados Unidos. Para el estudio morfometrico de las poblaciones venezolanas de Artemia, los nauplios fueron cultivados durante 20 dias bajo condiciones controladas a una salinidad 65 ppm, a una temperatura de 25°C y a una densidad de 50 individuos por litro en envases de 1-3 litros. Los nauplios fueron alimentados con las microalgas Dunaliella sp y Tetraselmis sp en una concentracion de 50.000 y 90.000 cel/mL respectivamente. Al obtener los primeros adultos, se tomaron al azar 30 hembras y 30 machos de cada una de las poblaciones y se le tomaron medidas de 12 caracteres morfometricos. Para maximizar las diferencias entre las medias de los diferentes grupos de observaciones, se empleo el metodo del analisis discriminante multivariado. Para este analisis, se incluyeron los datos de otras seis poblaciones americanas de Artemia (Caribe, Norte y Sur America). Entre las caracteristicas morfologicas que mas contribuyen en la separacion entre poblaciones, estan la longitud total, longitud de abdomen y el numero de sedas implantadas en las ramas derecha e izquierda de la furca. Los resultados de este trabajo sugieren que existen patrones morfometricos similares entre las poblaciones del Caribe estudiadas y la poblacion originaria (San Francisco Bay); esto pudiera indicar que las poblaciones venezolanas pertenecen a la especie Artemia franciscana (Kellogg, 1906) como se ha observado en la mayoria de las poblaciones del continente americano.

Starch gel electrophoresis was used to analyze the allelic variability of four polymorphic loci (Lap-2, Lap-3, Pgm and Gpi) from a single population of Artemia franciscana (Kellogg, 1906) from the Great Salt Lake (Utah, USA), cultured under eight different experimental conditions. The organisms were cultured to the adult stage under a 2 x 2 x 2 experimental design (22 and 30 degrees C; 30 and 60 ppt salinity; and Dunaliella sp. and Spirulina sp. as food). There were significant differences in allele frequencies at each locus and the mean expected heterozygosity (He) varied from 0.236 to 0.447. Therefore, the hypothesis of no allelic differences among treatments is rejected. With relation to a possible correlation between genetic variability and the phenotypic characteristics, the results show that there is probably a synergic effect between the different salinities and temperatures on the survival of heterozygous organisms in the different loci.

Starch gel electrophoresis was used to analyze the allelic variability of four polymorphic loci (Lap-2, Lap-3, Pgm and Gpi) from a single population of Artemia franciscana (Kellogg, 1906) from the Great Salt Lake (Utah, USA), cultured under eight different experimental conditions. The organisms were cultured to the adult stage under a 2x2x2 experimental design (22 and 30 C; 30 and 60 ppt salinity; and Dunaliella sp. and Spirulina sp. as food). There were significant differences in allele frequencies at each locus and the mean expected heterozygosity (He) varied from 0.236 to 0.447. Therefore, the hypothesis of no allelic differences among treatments is rejected. With relation to a possible correlation between genetic variability and the phenotypic characteristics, the results show that there is probably a synergic effect between the different salinities and temperatures on the survival of heterozygous organisms in the different loci.

The effect of different temperature and salinity combinations on the biochemical composition of Artemia franciscana from Venezuela and Mexico, is analyzed. Temperatures were 22 ± 0.5 °C, 26 ± 0.5 °C and 30 ± 0.5°C; salinities were 30‰, 60‰, and 120‰. Chaetoceros sp. was used as food. According to Tukey's Multiple Range Analysis for the A. franciscana population from Araya and San José, there were differences in the biochemical parameters and survival percentages among treatments and between populations. A positive correlation is observed among proximate composition values and survival, total length and growth rates. The observed variations reflect a genetic component resulting from the life history of the populations, and a non‐genetic component produced by the experimental conditions.

Quality evaluation tests were done on the strain of Artemia Las Cumaraguas, Paraguaná, Venezuela, in terms of cyst and naupliar (Instar 1) biometrics, as well as percentage, efficiency, rate and productivity of hatching. Bi-monthly sampling of cysts was carried out from January to September 1991. Simultaneously. temperature and salinity were measured. Average hydrated cyst diameter was 238.14 µm (s.d. ± 0.012). Average length of the nauplii (Instar 1) was 438.69 µm (s.d. ± 0.028) and average chorion thickness 1 1.36 µm (s.d. ± 0.012). Average hatching percentage and efficiency were 81.25% (s.d. ± 3.27) and 203.505 naupliiig (s.d. ± 20.95), respectively. As to hatching rate, T90 was observed at 24.14 hours and the hatching synchrony was obtained at 10.7 hours. Hatching productivity ranged from 184.3 to 354.53 mg/g of cysts. Results reveal the potentiality of Artemia from Las Cumaraguas and its possible use in aquaculture.