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Günther Nonell Jorge - One of the best experts on this subject based on the ideXlab platform.
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Growth of jaguar cichlid (Cichlasoma managuense) juveniles at different oxygen levels
Universidad Nacional de Costa Rica, 2016Co-Authors: Acosta Nassar Marco, Günther Nonell JorgeAbstract:The dependence of growth on the disolved oxygen level was analyzed in juveniles of the guapote tigre, Cichlasoma managuense, in a recirculated system. The guapote tigre is relatively tolerant to low oxygen levels, averaging only a 17% reduction in growth rate per ppm oxygen in the range between 2 and 5 ppm.Se investiga la relación de la tasa específica de crecimiento de juveniles del guapote tigre, Cichlasoma managuense, con el nivel de oxígeno disuelto en un sistema recirculado. El guapote tigre demuestra ser muy tolerante a condiciones hipóxicas, con una reducción en la tasa de crecimiento de solo 17% por ppm de oxígeno disuelto en el rango investigado desde 2 a 5 ppm
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Batch fertility and larval parameters of the jaguar cichlid (Cichlasoma managuense) spawned in the laboratory (ESP)
Universidad Nacional de Costa Rica, 2016Co-Authors: Günther Nonell Jorge, Boza Abarca JorgeAbstract:Se analizaron la fertilidad por puesta y los parámetros larvales de 32 puestas de guapote tigre (Cichlasoma managuense) en el laboratorio. Se demuestra una correlación positiva entre la fertilidad por puesta y el peso de la hembra, con puestas entre aproximadamente 3000 y 6000 larvas para hembras entre 100 y 500g de peso. No se encontró correlación significativa entre los parámetros larvales (peso fresco y % peso seco) y el peso de las hembrasBatch 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 about 3000 to 6000 larvae for females between 100 and 500 g wet weight. No significant correlation was found between larval parameters (fresh weight and % dry weight) and female weight
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Crecimiento del guapote lagunero (Cichlasoma dovii) en regimen de cultivo intenso en estanques y su dependencia de la densidad
Universidad Nacional de Costa Rica, 2016Co-Authors: Günther Nonell JorgeAbstract:Se determinan las características de crecimiento del guapote lagunero, Cichlasoma dovii, en régimen de cultivo intensivo en estanques de tierra y a dos densidades diferentes (1,4 y 2,8 peces /m2). El crecimiento y la utilización del alimento fueron aproximadamente 20% y 13% más ventajosos, con la densidad baja. Se determinó un acentuado dimorfismo sexual en peso (peso final promedio 317,2 y 113,9 g. para machos y hembras, respectivamente) y se utilizaron distribuciones de frecuencia para describir cuantitativamente el crecimiento de machos y hembras por separado.Growth and feed utilization of the Dow cichlid (Cichlasoma dovii) were assessed when cultured intensively in earthen ponds at two different densities (1,4 and 2.8 fish/m2). Growth and feed utilization were superior by 20% and 13%, respectively, at the lower density. A pronounced sexual difference in mean weight was detected (final weights 317,2 and 113,9g. for males and females, respectively) and frequency distributions were used to determinate separatedly the growth of males and females
Llerena Z. Cielo - One of the best experts on this subject based on the ideXlab platform.
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Ectoparasites in cultivated bujurqui (Cichlasoma amazonarum; Pisces: Cichlidae) reared in fish ponds.
Facultad de Medicina Veterinaria UNMSM., 2013Co-Authors: Lo P. Juan, Chávez V. Amanda, Contreras S. Guadalupe, Sandoval C. Nieves, Llerena Z. CieloAbstract:LO P., Juan, CHÁVEZ V., Amanda, CONTRERAS S., Guadalupe y SANDOVAL C., Nieves. Ectoparásitos en bujurqui (Cichlasoma amazonarum; Pisces: cichlidae) criados en estanques artificiales. Revista de Investigaciones Veterinarias del Perú [en línea]. 2011, vol. 22, no. 4, p. 351-359, ISSN 1682-3419.Los objetivos del presente estudio fueron identificar y establecer las frecuencias de ectoparásitos en Cichlasoma amazonarum (Pisces: Cichlidae) criados en estanques en la zona de Iquitos, Perú, entre octubre y diciembre de 2004. Se colectaron ectoparásitos de tegumento y branquias en 227 peces. Los parásitos fueron teñidos con Hematoxilina de Delafield. La frecuencia de infecciones por ectoparásitos fue de 78.0 ± 6.1% de monogeneos y 0.9% de maxillopoda (Crustacea: Branchiura). Dentro de los monogeneos, el 88.1% correspondió a parásitos de la familia Dactylogyridae, 6.2% a la familia Gyrodactylidae y 5.7% a infecciones mixtas de ambas familias. Los maxillopoda encontrados fueron de la especie Dolops geayi. El 80.2% de los peces muestreados presentaron de uno a tres parásitos por individuo, lo que indica niveles bajos que no afectan la salud de los peces. No se encontró una correlación significativa entre las medidas biométricas de los peces con la infección de monogeneos. Los resultados del presente estudio indican que la presencia de monogeneos en cíclidos amazónicos peruanos es común
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ECTOPARÁSITOS EN BUJURQUI (Cichlasoma amazonarum; PISCES: CICHLIDAE) CRIADOS EN ESTANQUES ARTIFICIALES
Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos, 2012Co-Authors: Lo P., Juan Lo P., Chávez V. Amanda, Contreras S. Guadalupe, Sandoval C. Nieves, Llerena Z. CieloAbstract:The aim of the present study was to identify ectoparasites and to establish the frequencies of infections in Cichlasoma amazonarum (Pisces: Cichlidae) raised in artificial ponds in Iquitos, Peru from October to December 2004. Ectoparasites collected from the skin and gills in 225 fish were stained using Delafield Hematoxiline. The frequency of ectoparasites was 78.0 ± 6.1% monogeneans and 0.9% maxillopoda (Crustacea: Branchiura). Among monogenean infections, 88.1% corresponded to parasites of Dactylofyridae family and 6.2% of Gyrodactylidae family, whereas 5.7% to mixed infections of both families. All maxillopoda found were Dolops geayi. One to three parasites per individual were found in 80.2% of the sampled fish, indicating of low parasite burden, which may no affect fish health. There was no significant correlation between biometric measurements and monogeneans infection in C. amazonarum. This study could indicate that monogeneans in Peruvian Amazon cichlids are common.Los objetivos del presente estudio fueron identificar y establecer las frecuencias de ectoparásitos en Cichlasoma amazonarum (Pisces: Cichlidae) criados en estanques en la zona de Iquitos, Perú, entre octubre y diciembre de 2004. Se colectaron ectoparásitos de tegumento y branquias en 227 peces. Los parásitos fueron teñidos con Hematoxilina de Delafield. La frecuencia de infecciones por ectoparásitos fue de 78.0 ± 6.1% de monogeneos y 0.9% de maxillopoda (Crustacea: Branchiura). Dentro de los monogeneos, el 88.1% correspondió a parásitos de la familia Dactylogyridae, 6.2% a la familia Gyrodactylidae y 5.7% a infecciones mixtas de ambas familias. Los maxillopoda encontrados fueron de la especie Dolops geayi. El 80.2% de los peces muestreados presentaron de uno a tres parásitos por individuo, lo que indica niveles bajos que no afectan la salud de los peces. No se encontró una correlación significativa entre las medidas biométricas de los peces con la infección de monogeneos. Los resultados del presente estudio indican que la presencia de monogeneos en cíclidos amazónicos peruanos es común
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ECTOPARASITES IN CULTIVATED BUJURQUI (Cichlasoma AMAZONARUM; PISCES: CICHLIDAE) REARED IN FISH PONDS
'Universidad Nacional Mayor de San Marcos Vicerectorado de Investigacion', 2011Co-Authors: Lo P. Juan, Chávez V. Amanda, Contreras S. Guadalupe, Sandoval C. Nieves, Llerena Z. CieloAbstract:Los objetivos del presente estudio fueron identificar y establecer las frecuencias de ectoparásitos en Cichlasoma amazonarum (Pisces: Cichlidae) criados en estanques en la zona de Iquitos, Perú, entre octubre y diciembre de 2004. Se colectaron ectoparásitos de tegumento y branquias en 227 peces. Los parásitos fueron teñidos con Hematoxilina de Delafield. La frecuencia de infecciones por ectoparásitos fue de 78.0 ± 6.1% de monogeneos y 0.9% de maxillopoda (Crustacea: Branchiura). Dentro de los monogeneos, el 88.1% correspondió a parásitos de la familia Dactylogyridae, 6.2% a la familia Gyrodactylidae y 5.7% a infecciones mixtas de ambas familias. Los maxillopoda encontrados fueron de la especie Dolops geayi. El 80.2% de los peces muestreados presentaron de uno a tres parásitos por individuo, lo que indica niveles bajos que no afectan la salud de los peces. No se encontró una correlación significativa entre las medidas biométricas de los peces con la infección de monogeneos. Los resultados del presente estudio indican que la presencia de monogeneos en cíclidos amazónicos peruanos es común.The aim of the present study was to identify ectoparasites and to establish the frequencies of infections in Cichlasoma amazonarum (Pisces: Cichlidae) raised in artificial ponds in Iquitos, Peru from October to December 2004. Ectoparasites collected from the skin and gills in 225 fish were stained using Delafield Hematoxiline. The frequency of ectoparasites was 78.0 ± 6.1% monogeneans and 0.9% maxillopoda (Crustacea: Branchiura). Among monogenean infections, 88.1% corresponded to parasites of Dactylofyridae family and 6.2% of Gyrodactylidae family, whereas 5.7% to mixed infections of both families. All maxillopoda found were Dolops geayi. One to three parasites per individual were found in 80.2% of the sampled fish, indicating of low parasite burden, which may no affect fish health. There was no significant correlation between biometric measurements and monogeneans infection in C. amazonarum. This study could indicate that monogeneans in Peruvian Amazon cichlids are common
Fabiana Lo L Nostro - One of the best experts on this subject based on the ideXlab platform.
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assessment of the acute toxicity of the organochlorine pesticide endosulfan in Cichlasoma dimerus teleostei perciformes
Ecotoxicology and Environmental Safety, 2011Co-Authors: Rodrigo Hernan Da Cuna, Graciela Rey Vazquez, Maria Natalia Piol, Noemi Verrengia R Guerrero, Maria Cristina Maggese, Fabiana Lo L NostroAbstract:Abstract The organochlorine insecticide endosulfan (ES) is widely used despite its high toxicity to fish (96-h LC50 median value of 2.6 μg L−1). This study aimed to assess the acute toxicity, histological and physiological parameters after exposure to 0; 0.25; 1; 2; 3; 4 and 16 μg L−1 ES for 96 h under semi-static conditions in a freshwater perciform fish, Cichlasoma dimerus. Prior to death, fish exhibited behavior indicative of neurotoxicity. No difference was found in brain AChE activity. A decrease in erythrocyte mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration in exposed fish suggests a state of anemia. Histological alterations observed in exposed fish included hyperplasia of the interlamellar epithelium, blood congestion in secondary lamellae, and mucous cells hyperplasia and hypertrophy in gills; pycnotic nuclei and hydropic degeneration in liver; testicular damage. These moderate pathological responses in major organs could become crucial during reproduction and under prolonged exposure periods.
Jorge Günther Nonell - One of the best experts on this subject based on the ideXlab platform.
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Growth of jaguar cichlid (Cichlasoma managuense) juveniles at different oxygen levels
Universidad Nacional, 2016Co-Authors: Marco Acosta Nassar, Jorge Günther NonellAbstract:The dependence of growth on the disolved oxygen level was analyzed in juveniles of the guapote tigre, Cichlasoma managuense, in a recirculated system. The guapote tigre is relatively tolerant to low oxygen levels, averaging only a 17% reduction in growth rate per ppm oxygen in the range between 2 and 5 ppm
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Crecimiento del guapote lagunero (Cichlasoma dovii) en regimen de cultivo intensivo en estanques y su dependencia de la densidad
Universidad Nacional, 2016Co-Authors: Jorge Günther NonellAbstract:Se determinan las características de crecimiento del guapote lagunero, Cichlasoma dovii, en régimen de cultivo intensivo en estanques de tierra y a dos densidades diferentes (1,4 y 2,8 peces /m2). El crecimiento y la utilización del alimento fueron aproximadamente 20% y 13% más ventajosos, con la densidad baja. Se determinó un acentuado dimorfismo sexual en peso (peso final promedio 317,2 y 113,9 g. para machos y hembras, respectivamente) y se utilizaron distribuciones de frecuencia para describir cuantitativamente el crecimiento de machos y hembras por separado
Victor M Vidalmartinez - One of the best experts on this subject based on the ideXlab platform.
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experimental infection of the mayan cichlid Cichlasoma urophthalmus with the oomycete aphanomyces invadans
Journal of Parasitology, 2015Co-Authors: Daniel Aguirreayala, Victor M VidalmartinezAbstract:Abstract: This study aimed to determine the susceptibility of the Mayan cichlid Cichlasoma urophthalmus to infection with the fungus Aphanomyces invadans (also known as epizootic ulcerative syndrome [EUS]). A total of 27 C. urophthalmus were exposed to the original A. Invadans 2006/86/EC strain by intramuscularly injecting the fish with 25,000 zoospores/ml or exposing the fish to a suspension of 25,000 zoospores/ml in 6-L aquaria for 30 days. To assess the infectious capacity of A. invadans, 3 golden barbs (Puntius semifasciolatus) were infected intramuscularly with 200,000 zoospores/ml. A second experiment using 100 C. urophthalmus was performed for 60 days with 50 fish in each treatment group. A polymerase chain reaction (PCR)-based diagnostic method was used; muscle and gills were the target tissues. In the first experiment, none of the exposed C. urophthalmus developed skin lesions related to A. invadans infection. However, PCR analysis revealed that infection had occurred. For the intramuscular trea...
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temporal variation of mexiconema Cichlasomae nematoda daniconematidae in the mayan cichlid fish Cichlasoma urophthalmus and its intermediate host argulus yucatanus from a tropical coastal lagoon
Parasitology, 2013Co-Authors: A L Maytec, Ma Leopoldina Aguirremacedo, D Pech, J W Lewis, Victor M VidalmartinezAbstract:The aim of the present investigation was to determine whether temporal variation in environmental factors such as rainfall or temperature influence long-term fluctuations in the prevalence and mean abundance of the nematode Mexiconema Cichlasomae in the cichlid fish Cichlasoma uropthalmus and its crustacean intermediate host, Argulus yucatanus. The study was undertaken in a tropical coastal lagoon in the Yucatan Peninsula (south-eastern Mexico) over an 8-year period. Variations in temperature, rainfall and monthly infection levels for both hosts were analysed using time series and cross-correlations to detect possible recurrent patterns. Infections of M. Cichlasomae in A. yucatanus showed annual peaks, while in C. urophthalmus peaks were bi-annual. The latter appear to be related to the accumulation of several generations of this nematode in C. urophthalmus. Rainfall and temperature appear to be key environmental factors in influencing temporal variation in the infection of M. Cichlasomae over periods longer than a year together with the accumulation of larval stages throughout time.
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branchiurids argulus as intermediate hosts of the daniconematid nematode mexiconema Cichlasomae
Folia Parasitologica, 1999Co-Authors: Frantisek Moravec, Victor M Vidalmartinez, Leopoldina AguirremacedoAbstract:At present the dracunculoid family Daniconematidae Moravec et Koie, 1987 includes two monotypic genera, Daniconema Moravec et Koie, 1987 and Mexiconema Moravec, Vidal et Salgado Maldonado, 1992; the former is represented by D. anguillae Moravec et Koie, 1987, a specific parasite of eels (Anguilla spp.) in Europe and North America, whereas the latter by M. Cichlasomae Moravec, Vidal et Salgado Maldonado, 1992, a parasite of cichlids and poeciliids in southern Mexico. The life cycles of these remarkable tissue parasites remained unknown and the only observation in this respect was that by Molnar and Moravec (Molnar K., Moravec F. 1994: Folia Parasitol. 41: 215-219), who had described thirdstage larvae of D. anguillae from the subcutaneous tissue of eels A. anguilla (L.) in Hungary. Molnar and Moravec (1994: op. cit.), Moravec et al. (Moravec F., Jimenez-Garcia M.I., Salgado-Maldonado G. 1998: Parasite 5: 289-293) and VidalMartinez et al. (Vidal-Martinez V. M., Kennedy C. R., Aguirre-Macedo M. L. 1998: J. Helminthol. 72: 199-207) have speculated that, because of the morphological similarity of these nematodes with skrjabillanids (see Tikhomirova V.A. 1980: Parazitologiya 14: 258-262), also their life cycle pattern may be similar to that of skrjabillanids, i. e. that ectoparasitic, haematophagous branchiurids (Argulus spp.) may serve as the intermediate host. Since Mexiconema Cichlasomae might be a serious problem in the newly established cultures of cichlids in southern Mexico, the elucidation of its life cycle is very important. Therefore, in November 1994, in an attempt to find the intermediate host of this parasite, we examined 139 specimens of Argulus sp. collected from the body surface of Cichlasoma urophthalmus (Gunther) from Celestun, Yucatan, Mexico, the locality where Salgado Maldonado (Salgado Maldonado G. 1993: Ph.D. thesis, CINVESTAV-IPN, Unidad Merida, 357 pp.) recorded 43% of C. urophthalmus infected by M. Cichlasomae; however, no nematode larvae were found in these crustaceans. A new attempt to find the larvae was made in May 1998, when 155 Argulus sp. collected from the same fish species were examined from Celestun; 2 of them (prevalence 1.29%, intensity 1 and 6 larvae) harboured small nematode larvae (103-196 μm long and 5-9 μm wide) in their haemocoel, located in the cephalothorax and natatory appendages. The small size of larvae suggests that they were advanced firstor second-stage larvae; Moravec et al. (Moravec F., Vidal V., Salgado Maldonado G. 1992: Folia Parasitol. 39: 33-40) reported the first-stage larvae of M. Cichlasomae from uterus to be about 180 μm long and 5-6 μm wide. Based on the measurements of larvae and the fact that no other dracunculoid species of the families Daniconematidae or Skrjabillanidae occurs in this region, the larvae from A. mexicanus can be considered to be M. Cichlasomae. The size of larvae suggests that both Argulus specimens acquired infection only recently. According to Salgado Maldonado (1993, op. cit.), M. Cichlasomae exhibits a pronounced seasonality in the occurrence in its fish host (C. urophthalmus) in Celestun, with the highest prevalence (up to 100%) and mean intensity (nearly 40) in the spring (April, May) and much lower prevalence and mean intensity in other months; this may explain why M. Cichlasomae larvae were recorded in Argulus in the spring (in 1998), but not in the autumn (in 1994). Although this preliminary report gives the first evidence about the intermediate host of a daniconematid nematode, the elucidation of the life cycle of M. Cichlasomae will require a detailed study, including the recognition of the parasite’s larval morphogenesis.
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the structuring process of the macroparasite community of an experimental population of Cichlasoma urophthalmus through time
Journal of Helminthology, 1998Co-Authors: Victor M Vidalmartinez, C R Kennedy, Ma Leopoldina AguirremacedoAbstract:The structuring process of the macroparasite community of caged Cichlasoma urophthalmus was studied over time using sentinel fish. Three thousand uninfected cichlids were stocked in floating cages introduced into a quarry in which a wild population of the same species was present. Caged and wild cichlids were sampled monthly over 6 and 7 months, respectively. Seventeen macroparasite species were found in the wild C. urophthalmus population, ten of which were detected in the caged population after 6 months. Early infections were by those species that were more frequent and abundant in the wild population, while helminths with a low prevalence and abundance in the wild appeared later in the caged fish population. The results suggested that the structuring process of the macroparasite community of caged C. urophthalmus followed a predictable pattern, in which those species that were most frequent and abundant in the wild were the first to establish in sentinel fish.
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ascocotyle a nunezae n sp digenea heterophyidae from yucatan mexico
Journal of Parasitology, 1997Co-Authors: Tomds Scholz, Victor M Vidalmartinez, Joaquin Vargasvazquez, Leopoldina AguirremacedoAbstract:A new heterophyid species, Ascocotyle (Ascocotyle) nunezae n. sp., is described from adults found in the intestine of naturally infected heron, Casmerodius albus (type host), from the coastal lagoon of Celestdn, Yucatan, Mexico, and a domestic chick (Gallus gallus), experimentally infected with metacercariae from Cichlasoma octofasciatum. The new species is character- ized mainly by the number (32-37) and arrangement of circumoral spines, which form 1 complete row of 25-27 circumoral spines and 6-10 accessory spines on the dorsal side, and by the morphology of the ventrogenital sac with a large gonotyl, consisting of 2 indistinctly separated lobes of vesicular tissue. Ascocotyle (A.) nunezae is placed into the nominotypical subgenus Ascocotyle because of the presence of uterine loops at the pharyngeal region and position of vitelline follicles. However, it differs distinctly from other members of this subgenus by the presence of long intestinal ceca reaching posterior to the ventral sucker. Cichlids of the genus Cichlasoma from cenotes, lakes, and the river Rifo Hondo in the Yucatan Peninsula were natural second intermediate hosts of A. (A.) nunezae, with metacercariae encysted on their gills. Cichlasoma meeki (Brind) was the most heavily infected fish host (total prevalence 75%; mean intensity 11 ? 9). Heterophyid metacercariae, designated as Ascocotyle (Phag- icola) sp. 3 by Scholz et al. (1995a), were found in the gills of cichlids of the genus Cichlasoma Swainson, 1839 during a study on the parasites of fish from cenotes (=sinkholes), small water bodies in the Peninsula of Yucatan, Mexico (Scholz et al., 1995b). Morphological studies of adult trematodes found in a naturally infected heron, Casmerodius albus (L.), and adults recovered from a domesticated chick, experimentally infected with these metacercariae, revealed that they represented a new, hitherto undescribed species of the genus Ascocotyle Looss, 1899. This species, for which the name Ascocotyle (Ascocotyle) nunezae is proposed, is described in the present paper.