Diet of 0+ brown trout (Salmo trutta L., 1758) from the river Erro (Navarra, north of Spain)

The diet composition of 41 0+ brown trout (Salmo trutta L., 1758) (33-97 mm TL) captured in August 2002 in the Erro River (North of Spain) is described. The diet was mainly composed by aquatic invertebrates. Excluding nematodes because they are possible parasites, the most consumed prey items were mayflies, dipterans, and crustaceans. Fingerling brown trout refused Chironomidae, Elmidae, and terrestrial invertebrates from the drift, and Elmidae, Heptageniidae, and Leuctridae from the benthos, while they showed preference for Rhyacophilidae from the benthos. Fingerling brown trout seems to act as an opportunistic predator, and the consumption of different preys seems to be influenced by their accessibility, predation risk, and their energetic value.Se analizó la dieta de 41 alevines de trucha común (Salmo trutta L., 1758) (33-97 mm LT) del río Erro (Norte de España). Su alimentación estuvo constituida principalmente por invertebrados acuáticos. Si no se tiene en cuenta a los nematodos por la posibilidad de tratarse de parásitos, las presas más consumidas fueron efémeras, dípteros y crustáceos. Los alevines de trucha común rechazaron los quironómidos, élmidos y los invertebrados terrestres de la deriva, así como los élmidos, heptagénidos y leúctridos del bentos, mientras que mostraron preferencia por los riacofílidos del bentos. Los alevines de trucha común parecen comportarse como depredadores oportunistas, pareciendo estar el consumo de las diferentes presas influenciado por su accesibilidad, el riesgo de predación y el valor energético de cada presa

Genomic analysis of bovine herpesvirus type 4 (BoHV-4) from Argentina: High genetic variability and novel phylogenetic groups

Bovine herpesvirus 4 (BoHV-4) is a γ-herpesvirus that has been isolated both from apparently healthy animals and from cattle with a variety of clinical signs, including post-partum endometritis and abortion. BoHV-4 causes either a persistent or a latent infection in cells of the monocyte/macrophage lineage. Two groups of BoVH-4 strains have been defined based on their restriction patterns: the Movar-like strains (European prototype) and the DN 599-like strains (American prototype). The purpose of the present study was to genetically characterize wild type BoHV-4 strains isolated from vaginal discharges of aborted cows in Argentina. The virus was identified by isolation and nested PCR in all vaginal discharge samples from aborted cows, either as a sole agent or in association with other pathogens. Restriction enzyme profiling and phylogenetic analysis demonstrated that there is a high genetic variability among the studied field isolates. The existence of three groups of strains, which were designated as genotypes 1, 2 and 3, is described. Genotypes 1 and 2 possibly correspond to the Movar-like and DN 599-like groups, respectively, whereas Genotype 3 corresponds to a novel group. Two viral strains did not cluster into any of these three groups, indicating that other genotypes could be circulating in Argentina. These results suggest a complex epidemiological background for the Argentinean BoHV-4 strains, probably influenced by independent events of genetic drift. This hypothesis cannot be rejected based on the available data. However, there is no direct evidence supporting this possibility. Thus, it seems speculative to suggest that interspecific jumps are responsible for the observed phylogenetic grouping. On the other hand, our analyses suggest a geographical structure for the observed viral genotypes, since genotypes 1 and 2 included the European (Movar-like) and American (DN599-like) reference strains, respectively. Geographic dispersion is known to be a driver of herpes viruses diversification, and independent evolution in geographical isolated places ensures the emergence of particular mutations in each location due to genetic drift (Compans, 2007; Zong et al., 1999). Therefore, at this point, the genetic drift hypothesis is the one that requires less ad-hoc considerations and thus, to our understanding, is the one that fits to the findings from this study. The involvement of this genetic variability in the detection and pathogenesis of BoHV-4 remains to be investigated.Fil: Verna, Andrea Elizabeth. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Manrique, Julieta Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; ArgentinaFil: Pérez, Sandra Elizabeth. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Leunda, M. R.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; ArgentinaFil: Pereyra, Susana Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; ArgentinaFil: Jones, Leandro Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentin

Effect of Dexamethasone in Neospora Caninum Seropositive Calves

The aim of this study was to evaluate the effect of Dexamethasone (DXM) on clinical parameters, absolute and differential leukocyte count, specific IgG titers, IFN-γ production and parasitemia in beef calves seropositive to Neospora caninum. Fifteen calves were assigned to four experimental groups as follow: group A: 4 sero- positive calves treated with DXM; group B: 4 seropositive calves without DXM; group C: 3 seronegative calves treated with DXM, and group D: 4 seronegative calves without DXM treatment. The absolute leukocyte count was higher in both groups A and C in the 3rd day after the first dose of DXM mainly due to a significant neutrophilia (p0.05). Similarly, IFN-γ levels did not change among experimental groups (p>0.05). DNA was de- tected in calves from groups A and B at 7 Days Post Administra- tion (dpa) and from group A at 14 dpa. Even when DXM adminis- tration induced hemotological parameter changes, no reactivation of Neospora-infection was observed according to specific IgG titers and presence of the parasite on leukocytes in naturally seropositive beef male calves.Fil: Idarraga Bedoya, S.. Universidad Nacional de Mar del Plata; ArgentinaFil: Armendano, Joaquín Ignacio. Universidad Nacional de Mar del Plata; ArgentinaFil: Gual, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Hecker, Yanina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leunda, M. R.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Pereyra, S.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Verna, Andrea Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Campero, C. M.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Odeón, Anselmo Carlos. Universidad Nacional de Mar del Plata; ArgentinaFil: Moore, Dadin Prando. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Effects of weir construction on fish population structure in the River Erro (North of Spain)

In 1996, a compound gauging weir was built in Villaveta Township (Navarra, North of Spain) in the river Erro (Ebro River Basin). Before and after its construction, fish and physical and chemical variables were examined to determine weir’s impact on the reach. Fish captured by electrofishing were measured (total length), and population density and length distribution of the species were estimated. Species diversity (Shannon’s diversity index), dominance (Simpson’s dominance index) and evenness were also calculated. The results revealed an increase in fish population density, especially in smaller specimens, but a decrease in the larger fishes. Substrate and shelter alterations could explain the observed variations in the fish community. In order to improve the consolidation of well-developed fish populations, the placement of great boulders and the restoration of the riparian vegetation are suggested

Spring diet composition of Rainbow Trout, Oncorhynchus mykiss (Walbaum, 1792) in the Urederra River (Spain)

This study describes the diet composition of 42 rainbow trout, Oncorhynchus mykiss (Walbaum, 1792) (90-480 mm TL), captured in May 1995 in the Urederra River (North of Spain). Rainbow trout of all sizes fed mainly on midge (adults, larvae and pupae), but there were some differences in the feeding habits of small and large fish. We found that as the trout grew larger terrestrial prey became the most important food item. Rainbow trout avoided Leuctridae and showed some preference for Ephemeroptera, Diptera larvae and Nemouridae larvae. Native fish predation and exploitation of the same trophic resources in the Urederra River, could negatively affect native fishes, such as European minnow, Phoxinus phoxinus L., 1758 or brown trout, Salmo trutta L., 1758

Toll-like receptor activation and expression in bovine alpha-herpesvirus infections

The involvement of Toll-like receptors (TLRs) in bovine herpesvirus types 1 (BoHV-1) and 5 (BoHV-5) infections has not been analyzed. In this study, the role of TLR signaling on virus replication was investigated. Blood leukocytes consistently express TLRs. Thus, our approach was to study in vitro the effects of agonist stimulation of TLRs expressed by peripheral blood leukocytes on BoHV-1 and BoHV-5 replication. Furthermore, the patterns of TLRs 3, 7–9 expression on virus-infected-bovine leukocytes were analyzed. Only Imiquimod (TLR7/8 agonist) showed anti-viral activity on infected MDBK cells. This is the first evidence that the timely activation of TLR7/8 signaling is effective in impairing BoHV-1 and 5 replication, thereby providing an experimental indication that Imiquimod may be a promising immune modulator. This work describes, for the first time, the expression patterns of TLRs in BoHV-1- or BoHV-5-infected-bovine leukocytes, suggesting the involvement of TLR7 and TLR9 in the recognition of these viruses.Fil: Marin, Maia Solange. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Quintana, Silvina. Instituto de Análisis Fares Taie. Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Faverin, Claudia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Leunda, M. R.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Perez, Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Escenarios, tempo e indicadores paleoambientales para la identificación del Antropoceno en el paisaje vegetal del Pirineo Central (NE Iberia) [Scenarios, timing and paleo-environmental indicators for the identification of Anthropocene in the vegetal landscape of the Central Pyrenees (NE Iberia)]

El Antropoceno puede considerarse como el origen de la configuración paisajística actual, y en relación a la vegetación, como el periodo en el que la intervención humana es el agente principal de los cambios que se producen de forma clara, intensa y permanente en el tiempo. En este trabajo se recopilan y comparan datos de secuencias palinológicas y de microcarbones, ocupaciones de yacimientos arqueológicos y dataciones de paleoincendios localizados en el Pirineo central, además de información documental, exponiendo una reflexión sobre las supuestas evidencias que promulgan una deforestación temprana y el uso del fuego de origen antrópico como señal inequívoca de intervención humana y surgimiento de los paisajes culturales desde hace milenios. En realidad, lo que se constata es una alta diversidad temporal y espacial entre todos los indicios, y sólo a partir de la Baja Edad Media (últimos 700 años, 1300 AD), los indicadores y valores de los mismos ofrecen auténtico consenso sobre el inicio de cambios consistentes y duraderos que marcarían el inicio del Antropoceno. The Anthropocene is related to the origin of current landscape configuration, and in terms of vegetation, with the consideration of human action as main forcing of clear, intense and permanent changes through time. In this paper we compile and compare data from palynological sequences, microcharcoal records, archaeological sites and radiocarbon dates from palaeofires located in the central Pyrenees besides historical documents, and we argue that some evidences related to early deforestation processes and use of human fire are not so clear than some authors point. Conversely, indicators of unequivocal human use and the origin of cultural landscapes are located only a few centuries and not a few millennia ago. In fact, high temporal and spatial variability is recorded until the Middle Ages (last 700 years, 1300 AD), when a series of consistent and permanent changes suggest the onset of the Anthropocene