Hidrobiológica (E-Journal)
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Detección molecular de enfermedades virales que afectan el desarrollo del cultivo del camarón*
Get PDFShrimp farming, as a productive activity, has had an exponential growth in coastal countries from the tropical and subtropical stripe, boosted by the development of several technologies. However, an important challenge still remains in order to achieve a greater yielding certainty: to eradicate the devastating epizootics provoked by viral agents. About 15 viruses are the cause of the worst economical disaster in farms from the Eastern and Western hemispheres. Several traditional diagnostic methods have been employed to detect the presence and assess the prevalence of pathogenic viruses in diverse cultured shrimp species, although their specificity, sensitivity, opportunity, and efficacy are questioned. On the other hand, molecular tools offer opportune detection, and specific diagnostics due to their high sensitivity, and easiness of interpretation. The designing of specific primers, and molecular probes is described. The methods used by the mentioned tools pursuing the detection and diagnose of the presence of viral agents in shrimps selected tissues are also described: amplification of selected genomic fragments by the use of specific primers in the polymerase chain reaction (PCR) or real-time PCR (qPCR), and specific hybridization molecular probes onto solid support (Dot-Blot) or in situ hybridization. Finally, a sanitary control strategy to eradicate the viral origin epizootics is proposed, based on the adequate and systematic application of methods employing molecular tools.El cultivo de camarón, como actividad productiva, ha tenido un crecimiento exponencial en los países costeros de la franja tropical y subtropical, impulsado por el desarrollo de diversas tecnologías. Sin embargo, aún persiste un importante reto para lograr mayor certidumbre de los rendimientos: erradicar las devastadoras epizootias provocadas por agentes virales. Son 15 los virus que hasta el momento han provocado los peores desastres económicos en granjas de los hemisferios este y oeste. Una serie de métodos tradicionales de diagnóstico han sido empleados para detectar la presencia y evaluar la prevalencia de virus patógenos en las diversas especies de camarón llevadas al cultivo, aunque su especificidad, sensibilidad, oportunidad y eficacia son cuestionadas. En contraste, se describe la opción de las herramientas moleculares como alternativa más adecuada para la detección oportuna y el diagnóstico específico, con muy alta sensibilidad y sencillez de interpretación. En el presente trabajo se presenta la manera en que se diseñan y construyen los iniciadores específicos y las sondas moleculares. Asimismo, se describen los métodos que emplean las mencionadas herramientas con el propósito de detectar y diagnosticar la presencia de agentes virales en tejidos selectos de camarón: la amplificación de fragmentos genómicos selectos mediante el uso de oligonucleótidos iniciadores específicos para la reacción de la polimerasa en cadena (PCR) o la PCR en tiempo real (qPCR) y la hibridación de sondas moleculares específicas sobre soporte sólido (Dot-Blot) o in situ. Finalmente, se propone una estrategia de control sanitario para la erradicación de las epizootias de origen viral, basada en la aplicación adecuada y sistemática de los métodos de detección que emplean herramientas moleculares
Inmovilización en campo del lobo marino de California (Zalophus californianus) con un equipo portátil de anestesia inhalada usando isofluorano
No full textThe field study was carried out on 11 rookeries in the Gulf of California in Mexico. A total of 288 pups and two adult females of the Califonia sea lion (Zalophus californianus) were anesthetized with isoflurane in a portable anesthesia machine. Duration of the anesthesia in the pups was six to 25 min (mean 12.51; SD ± 4.38). An average of 24 pups were worked with in each island, (a range of 16-29 animals), from an estimated two to 42 days of age, and six to 17.4 kg each (mean 10.41 kg; SD ± 2.02) totaling 137 males and 151 females. Induction in the adult females took from four to 10 minutes and they were anesthetized for one hour and twenty minute, presenting prolonged apneas. The inhaled anesthesia with isoflurane proved to be an effective and safe method for the inmobilization of free ranging California sea lion pups and adult females, and allowed us to obtain quality data in a situation of limited work time, rocky beaches and hot weather during the summer.El trabajo de campo se llevó a cabo en 11 loberas de reproducción del Golfo de California, México, en los meses de junio y julio durante la temporada de reproducción. Un total de 288 crias (137 machos; 151 hembras) y dos hembras adultas de lobo marino de California (Zalophus californianus) fueron anestesiadas con isofluorano con equipo potátil de anestesia inhalada. La duración de la anestesia en las crías fue de seis a 25 minutos (media 12.51; DS ± 4.38). Se manejaron 24 crías en promedio por isla (con un rango de 16 a 29 animales) de una edad de dos a 42 días y de seis a 17.4 kg de peso (media 10.4 kg; DS ± 2.02). En las hembras adultas el tiempo de inducción fue de cuatro a 10 minutos y se manejaron por un periodo de una hora veinte minutos, encontrando apneas prolongadas. La anestesia inhalada usando isofluorano probó ser eficaz y segura para la inmovilización de crías y hembras adultas de lobo marino de California en condiciones de campo, permitiendo la obtención de datos de calidad en una situación de tiempo limitada, playas rocosas y clima desértico en verano
Gross chemical composition of three common macroalgae and a sea grass on the Pacific coast of Baja California, Mexico
No full textChemical composition (moisture, crude protein, crude fibre, ether extractables, ash, and nitrogen-free extract) was determined in three marine algae and one sea grass of the Pacific coast of Baja California Sur. Samples of Eisenia arborea, Macrocystis pyrifera, Gelidium robustum and Phyllospadix torreyi from natural populations were evaluated in October 1995, and January, May and August 1996. Nitrogen-free extract, mainly carbohydrates, was the most important constituent in all specie, followed b ash, protein, crude fibre, and ether extractables (mainly lipids) in broen algae species. In red algae, protein content was higher than ash. Sea grass (P. torreyi) had high crude fibre, followed by ash, protein, and ether extractables
Biochemical characterization of crude extract from Pleuroncodes planipes (Crustacea: Galatheidae) as potential feed additive, considerations for a new fishery along the Mexico Pacific coast
No full textThe red crab Pleuroncodes planipes, commonly called "langostilla" is arguably the most abundant benthonic decapod of west coast Mexico, with natural productivity estimated at 735,000 metric tons/year. At the present time, it has not been exploited commercially. The implementation of a new fishery in Mexico, based on the capture of red carb, offers diversification of the fishing industry. In this work, a raw extract of langostilla, obtained by mechanical pressing of the whole organism, was analyzed as a potential feed ingredient or additive for cultured marine species. The lyophilized red crab extracts possessed: 1) enzymatic activity of protease, trypsin, amylase, and lipase; 2) no inhibition of serine-proteases; 3) antioxidant capacity against lipoperoxidation and superoxide ions produced by xanthine oxidase reaction; and 4) activity of insulin-like peptides. The amino acid profile shows high levels of arginine, lysine, and methionine. The cheical score of extract protein was compared with M. japonicus larvae, whole body fish tissue, and short-necked clam tissue. The digestibility of the product was 95% taking purified casein as reference. These biochemical and nutritional characteristics are discussed. These results offer a new use of red crab and the potential of a new fishery in Mexico
Hesperophycus y Silveta representantes de la familia Fucaceae (Fucales, Phaeophyta) en la costa del Pacífico de México
No full textA taxonomic revision of te family Fucaceae (Fucales, Phaeophyta) in Baja California is presented, together with a bibliography. Specimens housed in national and foreign herbaria were studied to obtain records and to corroborate their identification. Collecting trips were made along the western and eastern coasts of Baja California during 1990-1999. We conclude that the family Fucaceae is represented by Hesperophycus californicus P.C. Silva, Silvetia compressa (J. Agardh) Serr?o, Cho, Boo et Brawley and Silvetia compressa (J. Agardh) Serr?o, Cho, Boo et Brawley subsp. deliquescens P.C. Silva. All these taxa occur only on the western coast of the Peninsula. The southern limit of distribution of S. compressa subsp. compressa is extended 12 km from Punta Baja to Agua Blanca, Baja California. Morphological characters, reproductive phases, habitat, distribution, determination keys, and figurea are included.Se realizó la revisión taxonómica y bibliográfica de las especies de la familia Fucaceae (Fucales, Phaeophyta) que han sido registradas para el Pacífico Mexicanao. Además, se efectuaron análisis de los ejemplares depositados en herbarios nacionales y extranjeros con el fin de obtener los registros y corroborar su determinación, así mismo se realizaron campañas de recolecta en la zona intermareal a lo largo de la costa occidental y oriental de la Península de Baja California de 1990 a 1999. El análisis de esta información mostró que la familia Fucaceae se encuentra representada por Hesperophycus californicus P. C. Silva, Silvetia compressa (J. Agardh) Serr?o, Cho, Boo et Brawley y Silvetia compressa (J. Agardh) Serr?o, Cho, Boo et Brawley subsp. deliquescens P. C. Silva. Las especies de esta famiia se distribuyen sólo en la costa occidental de la Península. Se amplía en 12 km el límire sur de distribución geográfica de S. compressa subsp. compressa en la costa Pacífico de Norteamérica, de Punta Baja a Agua Blanca, Baja California. Para cada especie se incluyem datos relativos a sus características morfológicas, estadio reproductivo, hábitat, distribución, ejemplares examinados y una clave dicotómica para su determinación
El género Porphyra (Bangiaceae, Rhodophyta) en la costa Pacífico de México. II. Porphyra thuretii Setchell et Dawson
Get PDFOccurrence and seasonality of Porphyra thuretii Setchell et Dawson (Bangiaceae, Rhodophyta) is recorded for the Pacific coast of Mexico, based on sampling conducted in 1997, 2001 and 2002, and those deposited in national and foreign herbaria. P. thuretii is reported for first time for the coast of Sinaloa, México. We describe details of morfpho-anatomic characters and reproductive structures of the thallus, as well as its habitat and geographic distribution.Se registra la presencia y estacionalidad de Porphyra thuretii Setchell et Dawson (Bangiaceae, Rhodophyta)para la costa del Pacífico de México, con base en material recolectado durante 1997, 2001 y 2002, y deejemplares depositados en herbarios nacionales y extranjeros. Se registra por primera vez a P. thuretii para la costa del estado de Sinaloa, México. Se describen en forma detallada los caracteres morfo-anatómicos yestructuras reproductoras de los talos; así como su hábitat y distribución geográfica
Distribución y abundancia de los quetognatos de la plataforma Tamaulipeca y océano adyacente en abril de 1987
Get PDFAn analysis of Chaetognatha species distribution and abundance is presented for the northwestern region of the Gulf of Mexico. Zooplankton samples were collected during April 1987 at 16 collection sites located in front of the State of Tamaulipas. Thirteen species were recorded. Specific richness was lower at northwestern sites in front of Laguna Madre. Species with the highest density (2000 to 6000 orgs.100m-3) were Flaccisagitta enflata y Sagitta tenuis which were found towards the north of the area. The most frequent species collected throughout the sites were F. enflata and Serratosagitta serratodentata, the last one showed its highest densities in the southern region. Three groups of species were detected by using the Importance Value (IV): the first set included F. enflata, S. tenuis and S. serratodentata. Also two groups were defined when density data were analyzed by Morisita´s similarity index. The first included 7 northerly sites and the second, the most southern site. The last one shows a low Shannon diversity value (1.3 bits individual-1) and an intermediate Simpson´s dominance value (0.51). The second group included the rest of the 8 southern stations, with an average diversity of 2.2 bits individual-1 and a mean dominance of 0.27. A Principal Component analyses ran on abiotic variables grouped the stations in two sets: oceanic and neritic, this in turn agreed with the results of the similarity index. Chaetognaths species distribution and abundance were probably influenced by salinity and temperature.Se analiza la distribución y composición de las especies de quetognatos de 16 estaciones localizadas frente al estado de Tamaulipas en la parte oeste del Golfo de México. Las muestras fueron colectadas durante el crucero Justo Sierra realizado en abril de 1987. Se encontraron en total 13 especies, con la más baja riqueza hacia el norte del área de estudio frente a laguna Madre. Flaccisagitta enflata y Sagitta tenuis fueron las de mayor densidad, con valores entre 2000 y 6000 individuos100m-3 en la porción norte del área. F. enflata junto con Serratosagitta serratodentata estuvieron presentes en todas las estaciones, ésta última con las densidades más altas en la zona sur. Se detectaron tres grupos de especies mediante el Valor de Importancia, el primero incluyó a F. enflata, S. tenuis, S. serratodentata. Con la similitud de Morisita se definieron dos grupos de estaciones; el primero comprendió siete sitios ubicados al norte del área de estudio y la estación más sureña de todas, donde el promedio de la diversidad de Shannon fue bajo (1.3 bits individuo-1) y la dominancia de Simpson tuvo un valor intermedio (0.51). El segundo grupo lo formaron las siete estaciones restantes situadas al sur del área, con una diversidad promedio de 2.2 bits individuo-1 y la media de la dominancia de 0.27. El análisis de componentes principales permitió separar un conjunto de estaciones neríticas y otro de estaciones oceánicas, coincidiendo básicamente con los resultados del índice de similitud. La salinidad y la temperatura fueron los factores abióticos que probablemente influyeron en la distribución y abundancia de las especies de quetognatos en el área
Variaciones de la comunidad de copépodos plánticos en el gradiente estuarino-costero de Celestún,Yucatán, México
Get PDFZooplankton samples were collected monthly (from July 1994 to June 1995) to determine variations inabundance of planktonic copepods along the estuarine-coastal gradient in Celestun, Yucatan, México. From 17 copepod species, Acartia tonsa (51.8 %), A. lilljeborgii (12.2 %) and Pseudodiaptomus cokeri (30.8 %) were the most abundant species. Labidocera was the most diverse genus. Variation in species abundance was related mainly with gradients in salinity, temperature and biomass. The highest species richness was recorded in the mouth of the estuary due to a bigger exchange and mixture between the estuarine and marine fauna. The main features of the copepod community at Celestun are similar to those found in other regional coastal lagoons.Se efectuaron recolectas mensuales (julio de 1994 a junio de 1995) de zooplancton para determinar las variaciones de la abundancia de los copépodos pláncticos a través del gradiente estuarino-costero en Celestún, Yucatán. Se identificaron 17 especies de copépodos con Acartia tonsa (51.8 %), A. lilljeborgii (12.2 %) y Pseudodiaptomus cokeri (30.8 %) como las especies más abundantes, mientras que Labidocera fue el género más diverso. La variación en la abundancia de las especies se relacionó principalmente con los gradientes de temperatura, salinidad y biomasa zooplánctica . La mayor riqueza de especies se encontró en la boca del estero lo cual se debió a un mayor intercambio y mezcla de las faunas estuarina y marina. Las principales características de la comunidad de copépodos son similares a las encontradas en otras lagunas costeras de la región
Microelementos en nauplios de Artemia franciscana (Kellog, 1906) de seis poblaciones mexicanas y su relación con peces y crustáceos
Get PDFThis study describes the concentrations of iron (Fe), copper Cu, cinc (Zn), and manganese Mn for the nauplius stage of Artemia franciscana from six populations: Salinas de Hidalgo in the State of San Luis Potosi; Texcoco in the State of Mexico; Tres Hermanos, from Yavaros, State of Sonora; La Esperanza in Ohuira, State of Sinaloa; and Las Coloradas and Juchitán, State of Oaxaca. The determination of these elements was made from nauplii obtained from decapsulated and hatched cysts. The resulting nauplii were dried, pulverized and submitted to acid digestion. The determination was made by using an atomic absorption spectrum. The nauplii from San Luis Potosi showed the highest concentration of the four elements. Fe was the most abundant element in the nauplii of all six populations (506.91-1,469.16 mg/L). Zinc was in second place in quantity (75.30-155.47 mg/L). Copper was detected in all nauplii at high levels of concentration (24.23-101.76 mg/L) with respect to desirable amounts for catfish and peneid shrimp. Manganese was present in smaller amounts (15.88-28.76 mg/L) in all six populations and met the diet requirements of fish in general (20 to 50 mg/kg in thediet), only nauplii from Ohuira, and from the State of San Luis Potosí were able to cover their needs. Information on requirements for fish and shrimp larvae that feed on Artemia nauplii is scarce, therefore it is necessary to carry out more studies on this topic to support the development of suitable diets for cultivated these species.En este trabajo se presentan las concentraciones de fierro (Fe), cobre (Cu), zinc (Zn) y manganeso (Mn) en la etapa naupliar de Artemia franciscana de seis poblaciones mexicanas: las Salinas de Hidalgo, San Luis Potosí (SLP); Texcoco, Estado de México; Tres Hermanos, Yavaros, Sonora; La Esperanza, Ohuira, Sinaloa; Las Coloradas, Oaxaca y Juchitán, Oaxaca. La determinación de estos elementos se hizo a partir de nauplios eclosionados de quistes previamente descapsulados, los cuales se secaron y pulverizaron para posteriormente ser sometidos a una digestión ácida. Para la lectura de los datos, se utilizó un espectro de absorción atómica. Los nauplios de SLP fueron los que presentaron mayor concentración de los cuatro elementos. El Fe fue el elemento más abundante en los nauplios de las seis poblaciones (506.911469.19 mg/L). El zinc se encontró en segundo lugar en cuanto a cantidad (75.30155.47 mg/L). El cobre detectado en todos los nauplios alcanzó niveles altos (24.23101.76 mg/L), en relación con los requerimientos en peces como el bagre o los camarones peneidos. El manganeso se presentó en menor cantidad (15.8828.76 mg/L), en las seis poblaciones y de acuerdo con la demanda que tienen los peces en general (20 a 50 mg/kg en la dieta), solamente los nauplios de Ohuira, y de SLP, podrían cubrir los requisitos. La información es escasa sobre las necesidades de minerales que tienen las larvas de peces y camarones, que se alimentan de nauplios de Artemia; por lo que se considera necesario realizar más estudios sobre este tema y así poder desarrollar dietas adecuadas para estos organismos
Helminth parasites in feces of Antillean manatees Trichechus manatus manatus (Sirenia:Trichechidae) in Mexico: Gulf of Mexico and Caribbean
Get PDFBackground. Low helminth diversity has been reported in West Indian manatees (Trichechus manatus ). Most studies were conducted on the Florida sub species T. m. latirostris in subtropical environments, therefore limited information is available for the tropical Antillean subspecies T. m. manatus. In Mexico, there are apparently two population units of T. m. manatus. Goals. The objective of this study was to survey the presence and prevalence of helminth parasite eggs in the feces of T. m. manatus from the Gulf of Mexico (GM) and Caribbean coasts (CAR) of Mexico. Methods. We used 31 fecal samples collected from GM (n = 22) and CAR (n = 9), from 2005 to 2008. Feces were fixed and preserved in 70% ethanol until analysis. Both floatation and sedimentation techniques were used. Helminth eggs were identified using specialized literature and graphic catalogs. Results. We found parasite eggs in 61.2% of feces; all samples from CAR had helminths. We documented eggs from five helminths: three digenetic (Chiorchis fabaceus, C. groschafti, and Pulmonicola cochleotrema) and two Nematoda (Heterocheilus tunicatus and Ascarididae gen. sp.). Two species were found exclusively from GM, one exclusively from CAR, and two species were common to both locales. Conclusions. Diversity was consistently low in the samples. Four of the species found are common to Florida and Caribbean islands and one is a new registry for this host. Future examination of manatee carcasses could confirm the presence of adult helminth species for new registries for this host.Background. Low helminth diversity has been reported in West Indian manatees (Trichechus manatus ). Most studies were conducted on the Florida sub species T. m. latirostris in subtropical environments, therefore limited information is available for the tropical Antillean subspecies T. m. manatus. In Mexico, there are apparently two population units of T. m. manatus. Goals. The objective of this study was to survey the presence and prevalence of helminth parasite eggs in the feces of T. m. manatus from the Gulf of Mexico (GM) and Caribbean coasts (CAR) of Mexico. Methods. We used 31 fecal samples collected from GM (n = 22) and CAR (n = 9), from 2005 to 2008. Feces were fixed and preserved in 70% ethanol until analysis. Both floatation and sedimentation techniques were used. Helminth eggs were identified using specialized literature and graphic catalogs. Results. We found parasite eggs in 61.2% of feces; all samples from CAR had helminths. We documented eggs from five helminths: three digenetic (Chiorchis fabaceus, C. groschafti, and Pulmonicola cochleotrema) and two Nematoda (Heterocheilus tunicatus and Ascarididae gen. sp.). Two species were found exclusively from GM, one exclusively from CAR, and two species were common to both locales. Conclusions. Diversity was consistently low in the samples. Four of the species found are common to Florida and Caribbean islands and one is a new registry for this host. Future examination of manatee carcasses could confirm the presence of adult helminth species for new registries for this host