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1.
The present study reports the weight–length relationships of 22 fish species from middle stretches of the Paraíba do Sul River, a riverine system located in the most important economic regions of Brazil and which is under great pressure due to damming and others ventures. Data were collected quarterly in 2010 and 2011 from three reservoirs and the adjoining downstream by using three different mesh sizes of gill nets. Of the 22 species, eight had no records in the FishBase WLR database; new maximum lengths are given for eight species.  相似文献   

2.
Several methods for calculating indices of biological integrity (IBIs) have been developed for different ecogeographic regions of the world. All of them calculate IBI scores by comparing against reference sites or historical data on fish assemblage composition. Because of intensive agriculture and urbanization in our study area, we located no reference sites, and historical information about fish assemblage composition did not exist. Instead, we developed hypothetical reference scores based on seasonal electrofishing surveys at six study sites in adjacent but geomorphologically different watersheds. Our IBI included 10 metrics that varied with degree of degradation. We found that Shannon–Wiener indices varied significantly between seasons, indicating significant changes in species composition. Therefore, we calculated seasonal IBI scores also, but these did not significantly differ from each streams general IBI score, which was calculated on the basis of four samples per site. General stream IBI scores reflected differing levels of anthropogenic disturbance.  相似文献   

3.
This study presents data on behavioural acts performed by the Common Moorhen Gallinula chloropus in southern Brazil, and compares these with the behaviours previously reported for other populations. Focal observations of individuals were conducted in the municipality of Santa Maria, in the central region of the state of Rio Grande do Sul, Brazil. The sampling was done in 2-hour sessions, between January and March of 2007. A total of 20 behavioural acts, grouped in seven categories, were identified and described: locomotion (N = 5 acts), grooming (N = 4), intra-specific behaviour (N = 2), inter-specific behaviour (N = 3), foraging (N = 2), reproduction (N = 2) and rest (N = 2). Among the observed behaviours were acts that are not described in the literature such as greeting of offspring and some feeding acts. Regarding the use of habitat, we observed that this species has a preference for water or aquatic macrophytes, which is contrary to other reports. In the analysis of behavioural daily variation, overall behavioural categories did not vary significantly throughout the day, whereas we observed a significant difference in the use of categories during the periods 11:00 am–1:00 pm, 1:00–3:00 pm and 5:00–7:00 pm. The contrasting data between studies indicate that the variation between habitats and ecological interactions may generate different selective pressures on the behaviour of G. chloropus.  相似文献   

4.
Fish assemblage structure, rarefied species richness, species diversity and evenness of assemblages upstream of a reservoir in Oklahoma, U.S.A., were compared pre and post‐impoundment as well as in contemporary collections from streams above and below the reservoir. There were significant shifts in assemblage structure between historical and contemporary collections above the reservoir but not between contemporary assemblages above and below the impoundment. Indicator species analysis revealed that the sand shiner Notropis stramineus and fathead minnow Pimephales promelas have declined, whereas largemouth bass Micropterus salmoides and western mosquitofish Gambusia affinis have increased in relative abundance in assemblages upstream of the impoundment. Species richness was lower in contemporary assemblages compared with historical assemblages. Furthermore, contemporary assemblages below the dam had lower species richness, diversity and evenness compared with contemporary collections above the dam. These results highlight the spatial and temporal extent of reservoirs altering fish assemblages upstream of impoundments.  相似文献   

5.
Since 1942, when paracoccidioidomycosis was first identified in the state of Rio Grande do Sul, paracoccidioidal pulmonary lesions became a great concern to physicians. The present study focuses on 53 patients diagnosed over a seven-year period who presented paracoccidioidal lesions circumscribed to the lungs. These patients presented clinical and radiological features that simulated several pulmonary infectious and non-infectious conditions. Four unusual cases are briefly discussed. A sequence of laboratorial tests should be established for the diagnosis of pulmonary paracoccidioidomycosis. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

6.
An aerobiological study has been carried out in the region of Caxias do Sul in southern Brazil. Pollen monitoring was performed from January 1, 2001 through to December 31, 2002. A total of 30,469 pollen grains were collected during this period, and 40 pollen types were identified; of these, 23,389 pollen grains, representing 29 pollen types, originated from tree and shrub taxa. The maximum pollen concentration was registered in August 2001 and October 2002. In the study area, the pollen type Mimosa scabrella (18.8%) was much more abundant than all of the pollen types from tree and shrub taxa, such as: Urticaceae (18.4%), Myrtaceae (10.2%), Cupressaceae (7.7%), Myrsine (4.8%), Sorocea (3.9%), Pinaceae (2.9%), Asteraceae (2.2%) and Ricinus (2.1%). These nine pollen types accounted for the largest pollen concentrations of all the tree and shrub taxa. The pollen types Carya, Melastomataceae, Mimosa scabrella, Myrsine and Sorocea are reported for the first time in an aerobiological study in Brazil.  相似文献   

7.
Cryptococcosis is a major opportunistic mycosis which has meningitis as its most frequent clinical presentation and can be fatal in the absence of antifungal therapy. The aetiological agents are Cryptococcus neoformans, which affects mainly immunocompromised subjects, and C. gattii, the aetiologic agent for cryptococcosis in healthy individuals. A recent outbreak of cryptococcosis on Vancouver Island, Canada, raised the level of concern about the epidemiology of this disease. In Brazil, between 1980 and 2002, six per cent of AIDS patients had cryptococcosis in course at the time of diagnosis. To identify the profile of cryptococcal meningitis patients in Rio Grande do Sul (RS), Brazil, a retroactive study was realized using data from patients registered at Laboratório Central de Saúde Pública IPB-LACEN/RS from 2000 to 2005. Most of the patients were men (77.12%), Caucasian (83.5%), median age between thirty and thirty-nine years old (46.24%) and HIV positive (95%).  相似文献   

8.
Genetic aspects of hemophilias A and B in Rio Grande do Sul, Brazil   总被引:1,自引:0,他引:1  
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9.
Ctenomys minutus Nehring, 1887 inhabits fields and pastures of the coastal plains of Santa Catarina (SC) and Rio Grande do Sul (RS), southern Brazil. This species shows territoriality, low vagility, and sedentary behavior. The sexr atio is unbalanced; there are more females both in the general (1.3∶1) and in the adult population (1.26∶1). The population was sexually dimorphic, with males being significantly larger than females in all measured in dividuals. Analysis indicated allometric form of variation in both sexes.  相似文献   

10.
The effects of drought on fish assemblages were studied in the Indian Creek (228 km2) and Kings Creek (46 km2) watersheds located in the Piedmont Province of South Carolina. Water and fish samples were collected at 13 localities during drought conditions in 2000 and again under post-drought conditions in 2003. Abundance, species richness, and Simpson’s diversity were calculated for each locality, and the masses and lengths of individual fishes were measured to determine total biomass and length distributions for each species. Assemblages were significantly different from 2000 to 2003 at 10 of the 13 sample localities (χ2 test for association; p < 0.05). The family Cyprinidae (minnows) was numerically dominant in both years and in both watersheds, but their dominance declined somewhat following the drought due to lower numbers of Nocomis leptocephalus and Notropis lutipinnis in 2003 collections. However, some cyprinids increased in abundance in 2003 collections, most notably Semotilus atromaculatus and Hybopsis hypsinotus. Abundance of catostomids (suckers) and ictalurids (catfish) was also decreased post drought. Conversely, centrarchids (sunfish) increased in dominance in 2003, especially the species Lepomis macrochirus and Lepomis gulosus. Many more juveniles and young of the year were observed in 2003 collections, suggesting that most species exhibited greater reproductive success following the drought. The significant differences in water chemistry observed between the two years were not associated with any change in fish community structure. Instead, we attributed the observed differences in fish assemblages to changes in habitat structure associated with higher rainfall during post-drought conditions. Finally, sample localities showed high variability in common measures of assemblage structure, including abundance, species richness, and diversity. We hypothesize that the observed variability in community structure is caused by the heterogeneous habitat structure and morphology of these small Piedmont Province streams.  相似文献   

11.
Environmental Biology of Fishes - The objective was to explore levels of persistence and stability of a Neotropical fish assemblage in a typical Serra do Mar stream (Southeast Brazil) over...  相似文献   

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BackgroundThe number of fungal infections has increased in recent years in Rio Grande do Sul (RS), Brazil. Epidemiological studies are important for proper control of infections.AimsTo evaluate the etiology of fungal infections in patients in RS, from 2003 to 2015.MethodsThis is a retrospective and longitudinal study carried out at Mycology Department of Central Laboratory of RS; 13,707 samples were evaluated. The variables sex, age, site of infection, and etiologic agent were analyzed. Susceptibility of Candida to fluconazole was tested in isolates from samples collected in 2015 from 51 outpatients.ResultsOf the 13,707 samples, 840 cases (6.12%) of fungal infections were found and included in the analyses; female gender accounted for the 55.9% of the cases. The main fungus was Candida albicans (450 cases, 53.38%; p < 0.001). Onychomycosis was the most frequent infection in superficial mycoses. Systemic mycoses accounted for 54.05% of the cases, from which 68.8% occurred in males, mainly HIV-positive (33.11%), and the main etiologic agent in these cases was Cryptococcus neoformans (73.13%). Among 51 samples tested for susceptibility to fluconazole, 78.43% of Candida isolates were susceptible; 5.88% were susceptible in a dose-dependent manner, and 15.69% were resistant.ConclusionsC. albicans is a common cause of fungal infections in RS, accounting for half of the cases; resistance to antifungals was found in non-hospitalized patients. In addition, women seem to be more susceptible to fungal infections than men, however men show more systemic mycoses than women. The nails are the most common site of infection.  相似文献   

15.
BackgroundCurrent information on the epidemiology of physical inactivity among older adults is lacking, making it difficult to target the inactive and to plan for interventions to ameliorate adverse effects.ObjectivesTo present statewide representative findings on the prevalence of physical inactivity among older community residents, its correlates and associated health service use.MethodsA representative non-institutionalized random sample of 6963 individuals in Rio Grande do Sul, Brazil, aged ≥60 years, was interviewed face-to-face. Information was obtained on demographic characteristics, social resources, health conditions and behaviors, health service use, and physical inactivity. Controlled logistic regression was used to determine the association of physical inactivity with these characteristics.ResultsOverall, 62% reported no regular physical activity. Physical inactivity was significantly more prevalent among women, older persons, those with lower education and income, Afro-Brazilians (73%; White: 61%; “other”: 64%), those no longer married, and was associated with multiple individual health conditions and impaired activities of daily living (ADL). In adjusted analyses, associations remained for sociodemographic characteristics, social participation, impaired self-rated health, ADL, vision, and depression (odds ratios (OR) 1.2–1.7). Physically inactive respondents were less likely to report outpatient visits (OR 0.81), but more likely to be hospitalized (OR 1.41).ConclusionsPhysical inactivity is highly prevalent, particularly among Afro -Brazilians. It is associated with adverse sociodemographic characteristics; lack of social interaction; and poor self-rated health, ADL, vision, and depression; although not with other health conditions. Self-care may be neglected, resulting in hospitalization.  相似文献   

16.
Of a total of 101 fish species caught in the Lower Miranda River floodplain, 29 were omnivorous, 16 ichthyophagous, 12 herbivorous, 18 detritivorous, 8 zooplanktophagous, 7 insectivorous, 2 lepidophagous, 4 ichthyophagous/insectivorous and 4 zooplanktophagous/insectivorous. Almost half of the species belong to omnivorous and detritivorous trophic guilds. The same is not true when biomass is considered. The number of fish species by trophic guild didn't change along the year whereas the biomass changed significantly. The frequency of abundant fish species was not the same for the sampled environments.  相似文献   

17.
The community structure of two confluent streams in southern Sweden was investigated, one stream was spring-fed and the other lake-fed. There was a downstream decrease in the number of species present in the lake outlet stream, no such change being discernible in the spring-fed stream. Taking the sampling site nearest the source of the spring-fed stream as the reference point, there was a downstream increase in dissimilarity and this increase was maintained upstream from the confluence in the lake-fed stream. Apart from generalists, all functional feeding groups showed decreased numbers from the lake outlet to the confluence in the lake-fed stream. In the spring-fed stream, densities of functional groups increased downstream, with the exception of grazers and generalists. There were indications of more predictable changes along the lake-fed stream compared to the spring-fed one, which seemed more influenced by site-specific factors.  相似文献   

18.
Ecosystems are linked by the movement of organisms across habitat boundaries and the arrangement of habitat patches can affect species abundance and composition. In tropical seascapes many coral reef fishes settle in adjacent habitats and undergo ontogenetic habitat shifts to coral reefs as they grow. Few studies have attempted to measure at what distances from nursery habitats these fish migrations (connectivity) cease to exist and how the abundance, biomass and proportion of nursery species change on coral reefs along distance gradients away from nursery areas. The present study examines seascape spatial arrangement, including distances between habitats, and its consequences on connectivity within a tropical seascape in Mozambique using a seascape ecology approach. Fish and habitat surveys were undertaken in 2016/2017 and a thematic habitat map was created in ArcGIS, where cover and distances between habitat patches were calculated. Distance to mangroves and seagrasses were significant predictors for abundance and biomass of most nursery species. The proportions of nursery species were highest in the south of the archipelago, where mangroves were present and decreased with distance to nurseries (mangroves and seagrasses). Some nursery species were absent on reef sites farthest from nursery habitats, at 80 km from mangroves and at 12 km from seagrass habitats. The proportion of nursery/non-nursery snapper and parrotfish species, as well as abundance and biomass of seagrass nursery species abruptly declined at 8 km from seagrass habitats, indicating a threshold distance at which migrations may cease. Additionally, reefs isolated by large stretches of sand and deep water had very low abundances of several nursery species despite being within moderate distances from nursery habitats. This highlights the importance of considering the matrix (sand and deep water) as barriers for fish migration.  相似文献   

19.
The discovery of two groups of the black howler monkey,Alouatta caraya, inhabiting two orchards on a cattle farm, Fazenda Casa Branca (29°56′S, 55°59′W), Rio Grande do Sul State, Brazil, represents a new southern limit for the geographic distribution of this species.  相似文献   

20.
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