NEOTROPICAL FRESHWATER FISHES: A dataset of occurrence and abundance of freshwater fishes in the Neotropics

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.

New vascular structure in broiler breast: breast-vessel

Chickens intensively selected for accelerating growth rate and enhanced muscle mass has resulted in the occurrence of breast alterations with a negative consumers perception. Together with the already known breast abnormalities (White Striping, Wooden Breast and Spaghetti Meat) a new one has been described by the consumers as a "long and thin worm". For this reason, the aim of this work was to macroscopically and microscopically describe this structure in broiler breast. To this end, 2 different experiments were performed. In the first one, 4 broiler breasts from a supermarket were analysed. Thereafter, a second experiment was carried out on an experimental farm simulating field management conditions in order to confirm the results of the first experiment. To this end, 120 chickens were reared in an experimental farm up to 42 d. Breast samples were collected and analysed macroscopically and microscopically to assess the abnormality on the broiler breast. In both experiments, the results of the analysis showed the finding of tubular structures located on the surface of pectoralis major muscle compatible with arteries. So far, currently, this occurrence has not been described in the literature and we propose calling this new broiler breast feature as breast-vessel.

Effect of gradual temperature increase on the carbohydrate energy metabolism responses of the Antarctic fish Notothenia rossii

The warming of the Southern Ocean waters may affect the biological processes and the performance of the fish inhabiting it. The notothenioid group is metabolically specialized to low-temperature environments and may be vulnerable to the climatic changes imposed on the Antarctic continent. However, gradual temperature changes potentially allow an opportunity for plasticity adjustments. The present study evaluated the effect of gradual increase of temperature on the enzymatic and nonenzymatic parameters of energy metabolism in renal, branchial, hepatic, and encephalic tissue of Notothenia rossii subjected to a gradual temperature change of 0.5 °C/day until reaching 2 °C, 4 °C, 6 °C, and 8 °C. Under the effect of an acclimation rate of 0.5 °C/day, the gill tissue showed increased phosphofructokinase (PFK) enzyme activity. In the kidney, there was increased activity of the malate dehydrogenase (MDH), glucose-6-phosphatase (G6PDH), and glycogen phosphorylase (GP) enzymes. There was an increase in lactate concentration in the liver and an increase in GP enzyme activity in the brain. The specific tissue responses indicate the presence of thermal plasticity and an attempt to regulate energy metabolism to mitigate thermal stress in this species under these experimental conditions, possibly through the activation of glycolysis, gluconeogenesis, and glycogenolysis.

Estrutura da ictiofauna do rio Bonito, bacia hidrográfica do rio Ivaí, sistema alto rio Paraná, Brasil

A diversidade da ictiofauna da bacia do rio Ivaí é altamente subestimada. O presente estudo teve como objetivo caracterizar a ictiofauna do rio Bonito, um tributário do rio Ivaí, bacia do alto rio Paraná, quanto à riqueza, diversidade e constância de espécies. Foram estabelecidos três locais de amostragem ao longo do gradiente longitudinal do rio: cabeceira, trecho médio e região de desembocadura próxima ao rio Ivaí. Três incursões de coleta foram feitas em cada unidade utilizando redes de espera de diferentes malhas, tarrafas e covos. A ictiofauna foi composta por 23 espécies, divididas em nove famílias e três ordens. Entre as espécies coletadas, três delas são possíveis novos registros para o alto rio Paraná e 12 para a bacia do rio Ivaí. A maior riqueza foi registrada no trecho inferior, onde foram encontradas 20 espécies, o qual também apresentou maior diversidade e menor dominância de espécies. No trecho médio do rio foram coletadas sete espécies e no trecho superior apenas uma. No baixo rio Bonito a maioria das espécies foram acessórias e no trecho médio cinco foram constantes e apenas uma acessória. O trecho médio apresentou maior dominância de espécies, com destaque para Hypostomus aff. ancistroides. O gradiente altitudinal foi um importante fator estruturador da assembleia de peixes do rio Bonito, delimitando as assembleias ao longo do gradiente longitudinal.

Strains of Staphylococcus aureus and pathology associated with chronic suppurative mastitis in rabbits

Staphylococcal mastitis is one of the main reasons for culling adult does from commercial rabbitries. The aim of this study was describe the spectrum of gross and microscopic lesions in 178 cases of chronic staphylococcal mastitis in adult does and to determine whether there is a correlation between Staphylococcus aureus genotypes and pathology. On the basis of histopathology, chronic mastitis was differentiated into abscesses (66.3%), suppurative mastitis with a lobular pattern (7.9%), cellulitis (19.6%) and mixed lesions (6.2%). Pathological presentations were not related to S. aureus genotype.

Staphylococcal infections in rabbit does on two industrial farms

The main reasons for culling adult rabbit does on two Spanish rabbit farms were investigated for a year. The most important conditions were mastitis (33.3 per cent), followed by subcutaneous abscesses (9.9 per cent) and pyometra (8.7 per cent). Staphylococcus aureus infections were the most severe problem, the organism being isolated from 69.2 per cent of infected animals. Pasteurella species were more prevalent in cases of pyometra and pneumonia. Two strains of S aureus were identified by using polymorphism of the coagulase gene as the criterion. One of these strains was responsible for the majority of the staphylococcal infections and was isolated from several pathological processes.

Genotypic characterization of Staphylococcus aureus strains isolated from rabbit lesions

Since staphylococcal infections are the main pathological problem in rabbit does, the objective of this study was to characterize epidemiologically Staphylococcus aureus isolates from different lesion types in rabbits. Using 3 genetic markers (coagulase, staphylococcal protein A and clumping factor B genes), 22 different genotypes were identified among 301 isolates recovered from 259 rabbit does with 10 different kinds of chronic purulent lesions. These infected rabbits were obtained from 30 herds located in the Valencia province on the Spanish Mediterranean coast. The most frequent genotype was designated A1/II1/delta (coa/spa/clfB combination genotype) and represented 70.76% of the isolates. Although most genotypes were previously identified in other countries, novel types were also documented. No specificity between genotypes and nature of the pathologic process could be identified. After genetic comparison between strains from different origins, the results may suggest that rabbit, bovine and human S. aureus isolates are not clonally related, suggesting that specific host-dependent pathogenic factors may have evolved independently in these species. These differences indicate that a rational and effective strategy to control infections caused by rabbit-specific isolates may be advantageous.

Cancer risk around the nuclear power plants of Trillo and Zorita (Spain)

AIM

To investigate the association between cancer risk and proximity of place of residence to the Guadalajara nuclear power plants: Trillo and Zorita.

METHODS

Case-control study. Cases were patients admitted with cancer and controls were non-tumorous patients, both admitted to Guadalajara Hospital (period 1988-99). Exposure factor: place of residence (areas within 10, 20, and 30 km of each plant). Odds ratios (ORs) of those areas closest to the plants were calculated with respect to those furthest away; a linear trend analysis was also performed.

RESULTS

In the extreme areas in the vicinity of Trillo, an OR of 1.71 was obtained (95% CI 1.15 to 2.53), increasing in magnitude in the subgroup of more radioinducible tumours and in the period considered as post-latency (1997-99). Risk increased linearly with proximity to the two plants, significantly in Trillo (p < 0.01) but not in Zorita (p = 0.19).

CONCLUSIONS

There is an association between proximity of residence to Trillo and cancer risk, although the limitations of the study should be kept in mind when interpreting the possible causal relation.