Abstract in English:The present study investigated the effects of propolis and vitamin E supplementation in diets of juvenil rainbow trout subjected to two different flow rates with or without flow stress (0.9 and 2.1 l/min, respectively) on final weigth (FW), condition factor (CF), feed conservation ratio (FCR), protein efficiency ratio (PER) and vitamin A, C and E concentrations and malondialdehyde (MDA) levels in serum as well as plasma superoxide dismutase (SOD) activity. The experimental groups were as follows: group C was fed a basal diet, group P10 was fed a basal diet supplemented with 10 g propolis/kg, group P30 was fed a basal diet supplemented with 30 g propolis/kg, group E60 was fed a basal diet supplemented with 60 mg vitamin E/kg. CF and PER were not different among all diets groups for both flow rate treatments (p > 0.05). The FCR improved in P10, P30 and E60 diet groups compared to C diet group at 2.1 l/min flow rate (p < 0.05). The FCR of E60 and P30 were found to be better than C and P10 diet groups at 0.9 l/min flow rate (p < 0.05). Vitamin E and propolis supplementations did not affect vitamin A concentration of serum for either flow rate (p > 0.05). Fish fed with diet E60had higher serum vitamin E concentration than other groups (p < 0.05). Serum Vitamin C concentration was only affected by the propolis supplemented diets. MDA level of E60 group was found significantly lower comperad to other groups for both flow rate (p < 0.05). Plasma SOD activity significantly decreased in the E60 group compared to other groups at 2.1 l/min flow rate (p < 0.05). But plasma SOD activity was not different among all diets groups at 0.9 l/min flow rate (p > 0.05).
Abstract in English:We investigated the reactions of four bat species from four different lineages to UV light: Hipposideros armiger (Hodgson, 1835) and Scotophilus kuhlii Leach, 1821, which use constant frequency (CF) or frequency modulation (FM) echolocation, respectively; and Rousettus leschenaultii (Desmarest, 1820) and Cynopterus sphinx (Vahl, 1797), cave and tree-roosting Old World fruit bats, respectively. Following acclimation and training involving aversive stimuli when exposed to UV light, individuals of S. kuhlii and C. sphinx exposed to such stimuli displayed conditioned reflexes such as body crouching, wing retracting, horizontal crawling, flying and/or vocalization, whereas individuals of H. armiger and R. leschenaultii, in most cue-testing sessions, remained still on receiving the stimuli. Our behavioral study provides direct evidence for the diversity of cone-based UV vision in the order Chiroptera and further supports our earlier postulate that, due to possible sensory tradeoffs and roosting ecology, defects in the short wavelength opsin genes have resulted in loss of UV vision in CF bats, but not in FM bats. In addition, Old World fruit bats roosting in caves have lost UV vision, but those roosting in trees have not. Bats are thus the third mammalian taxon to retain ancestral cone-based UV sensitivity in some species.
Abstract in English:We investigated the density and activity of the oncilla, Leopardus tigrinus (Schreber, 1775), a threatened small cat, in the Brazilian Atlantic Forest, using camera-trap data. We described differences in the activity of individuals occurring alone or in sympatry with larger cats. Oncilla presented low densities (7-13 ind./100 km²) and high flexibility in its activity. The oncillas were primarily nocturnal in the absence of other larger cat species - margay, ocelot and puma - but became more diurnal, with a cathemeral activity pattern, when the other cats were present. Oncilla is likely to be in a subordinate position in interactions with larger cats and changes its activity to decrease the chances for interspecific encounters. In this study, however, the presence of other cat species covaries with habitat changes (from coastal forest patches to dense evergreen forests). We also verified the highest oncilla relative abundance in an area with no sympatric larger cats, with abundance decreasing when it was in sympatry with margay, ocelot and puma. Our results, together with recent records of oncilla in other degraded landscapes of the Atlantic Forest of Brazil, provide evidence that oncillas may thrive even in harsh environments where other cats have already been extinct. This raise interesting conservation insights, as in the absence of other cats, L. tigrinus may assume a top predator role of these impoverished vertebrate communities.
Abstract in English:The replacement and growth of 311 primary feathers of eight captive male rock pigeons, Columba livia Gmelin, 1789 were monitored daily. Feather replacement was recorded in all months, but the primaries 1 to 5 (innermost primaries) were replaced mostly from September to December, whereas the primaries 6 to 10 (outermost primaries) were more frequently replaced from January to August. Each primary was held in plumage from six to fifteen months, but the lifetime of the outer feathers was longer than that of the inner feathers. A new primary emerges two or three days after its predecessor has been dropped, but the primaries replacing the feathers accidentally lost during bird handling emerge only after about eight days. The average growth period of a primary ranged from 21 to 37 days, with the larger and outermost feathers exhibiting a longer growth period. A constant average growth rate of 4 to 5 mm/day was found for all primaries until the last two days of growth, when the growth rate of the feathers became progressively slower. Bilateral symmetry in the primary replacement, when the same feather is replaced simultaneously in both wings, was not significant (22.2%) in the birds monitored in this study.
Abstract in English:Invasion by marine species, often considered a grave threat to marine ecosystems, occurs throughout the world as a consequence of many anthropogenic activities. In coastal Paraná, many factors including shipping, aquaculture and the use of artificial substrates provide suitable environments for the establishment and rapid spread of introduced marine species. To better understand this process, the encrusting community was studied on polyethylene plates (n = 120, 10 x 10 cm) that were placed seasonally at fixed locations on the inner continental shelf to detect non-native species. Of the 62 taxa found, 40 were identified to species, 14 of which were native, 9 introduced and 17 cryptogenic. We found a new introduction while most introduced species were previously reported at a nearby estuary with an international port. Possible complementary explanations for these detections are 1) estuaries influence ecological processes on the inner continental shelf, 2) the study area is near the route of cargo and other ships entering the port, 3) other local vectors, such as hulls of fishing and recreational boats, and artificial reefs link the estuary to the offshore areas. Thus, not only are estuaries invaded by exotic species, but also non-indigenous marine species may be present in the open sea where they are likely to colonize artificial substrates.
Abstract in English:Coastal regions are subject to various forms of environmental impacts, such as spills of crude oil and associated products, with a wide range of effects on benthic biodiversity. This study characterized the patterns of recolonization of the macrofauna associated with the brown alga Sargassum cymosum(C. Agardh), on fronds contaminated by diesel oil in a small-scale field experiment. We collected 40 fronds of S. cymosum from an algal bed in southeastern Brazil and defaunated each frond by immersion in fresh water. Half of the fronds were then immersed in seawater (control group) and the other half in a mixture of 50% diesel oil and 50% seawater (impacted group). The test fronds were returned to the algal bed, and natural recolonization took place over a period of 12 days. Samples of the vagile macrofauna were taken randomly at three-day intervals over the course of the recolonization period. No significant differences in the densities of most taxa were found between the impact treatment (IG) and control treatment (CG). At the end of the recolonization period (day 12), the faunal composition of the treated fronds was very similar to the natural conditions, indicating a high rate of community recovery and suggesting that benthic associations can be rather resilient to diesel-oil impacts on a small scale.
Abstract in English:The thalassinideans (Axiidea and Gebiidea) encompasses approximately 615 species with reclusive habits, generally confined to extensive galleries burrowed into the sand or mud and, more rarely, in openings in reefs or the cavities of sessile animals such as sponges and coral. These species use the galleries for shelter, feeding and breeding, except during the pelagic larval stage. They inhabit estuaries, bays, lagoons, beaches, seas and both tropical and temperate oceanic areas throughout the world, distributed predominantly in the intertidal zone (mid-littoral and infralittoral zones). The aim of the present study was to assess the species composition and abundance of thalassinideans, comparing two micro-habitats (consolidated and non-consolidated substrates), and determine whether there is a correlation between abundance of the organisms and time of the year, collection sites or salinity. Twelve monthly samplings were carried out between August 2006 and July 2007 over consolidated and non-consolidated bottoms of the upper and lower portions of the mid-littoral zones, with three sub-samplings, totaling 48 monthly samples and 576 in all. A total of 651 individuals were collected - 114 Lepidophthalmus siriboia Felder & Rodrigues, 1993 and 537 Upogebia vasquezi Ngoc-Ho, 1989. There was correlation between the abundance of both species and salinity, but U. vasquezi was more abundant in the rainy season. Lepidophthalmus siriboia appears to prefer non-consolidated substrates, whereas U. vasquezi prefers consolidated substrates. The recruitment period for the callianassid L. siriboia appears to occur in just two periods of the year and is more intense in the dry season, whereas U. vasquezi is more frequent throughout the year. The smallest and largest sizes (carapace length - CL) recorded for L. siriboia were smaller than those recorded for the species in northeastern region of Brazil. CL values for ovigerous females suggest that U. vasquezi reaches sexual maturity at a smaller size than L. siriboia.
Abstract in English:Individual samples from five populations of the characid fish Astyanax scabripinnis (Jenyns, 1842) from the Tietê and Paranapanema river basins (Brazil) were studied. All individuals analyzed presented 50 chromosomes but three different karyotypic forms were observed. Additionally, some individuals of one karyomorph presented a macro supernumerary chromosome. No chromosomal differentiation was observed between males and females in any sample analyzed. C-banding revealed two distinct distribution patterns in these populations in which strong terminally located heterochromatic blocks were detected in the long arms of some chromosomes of the specimens from Cascatinha, Cintra, and Funari streams, whereas populations of the Capão Bonito stream and the Barbosa waterfall revealed less evident heterochromatic blocks on the chromosomes. The comparative study of the 18S rDNA localization by fluorescent in situ hybridization, and detection of active nucleolus organizing regions by silver stain (Ag-NORs) showed differences in rDNA content and expression of this gene site among the individuals analyzed. Chromosome mapping of the 5S rDNA revealed the presence of four sites located in two distinct chromosomal pairs, with no apparent differences among karyomorphs. Based on the biogeographical distribution and specific biological characteristics of the species, the data focus on the chromosome differentiation mechanisms involved in the speciation process acting on the populations of the Astyanax scabripinnis species complex.
Abstract in English:Species of Chironomidae are widely used as bioindicators of water quality, since their larvae undergo morphological deformities when in contact with sediment contaminated with chemicals. In this work we endeavored to study the morphology of head structures (antennae, mandible, mentum, pecten epipharyngis, ventromental plate and premandible) throughout the development of the four larval instars of Chironomus sancticaroli Strixino & Strixino, 1981, which can be used in environmental impact analyses. Our results show that it is possible to differentiate among larval instars by doing a quantitative analysis on the number of striae on the ventromental plates. The six structures analyzed changed during larval ontogeny. These changes are part of the ontogeny of the immature stages not exposed to xenobiotics. We believe that the morphological pattern defined in this work can be used for comparisons with ontogenetic changes observed in field studies conducted in polluted environments.
Abstract in English:The freshwater copepod Odontodiaptomus thomseni (Brehm, 1933) (Calanoida: Diaptomidae) is a rare species that has been reported only once - in its original description (BREHM 1933). The lack of subsequent records led to its inclusion in the Red List of threatened species (IUCN). Here we present a new record for O.thomseni. It was discovered in Salto Grande reservoir, which is located in the lower stretches of the Uruguay River, between Uruguay and Argentina, at the River Plate basin. In January 2010, three specimens (two males and one female) were found, and these were studied in detail using scanning electron microscopy (SEM). We only had material of Odontodiaptomus paulistanus (Wright, 1936) for comparison, but the position of the lateral spine in right P5 of the male, and the shape and size of lateral wings of the female are especially distinctive. Odontodiaptomus thomseni remains a rare species and we recommend keeping it on the IUCN Red List.
Abstract in English:In Brazil, there are two published references on the diet of American kestrel falcons, Falco sparverius Linnaeus, 1758, and one is for the Cerrado biome. The only mammal prey so far found in the diet of F. sparverius was the rodent Calomys tener (Winge, 1887). Herein we report on daily hunting activities by American kestrel falcons at a factory in the city of Uberlândia, state of Minas Gerais, southeastern Brazil, during an attempt to remove a bat colony. Two American kestrel falcons were observed on 14 occasions during two consecutive days: in two of these occasions, they were hunting in pairs, from 12:00 p.m. to 3:00 p.m. on 06/X/2003, and from 07:00 a.m. to 11:00 a.m. on 07/X/2003. During this period, American kestrel falcons made 27 hunting attempts and captured four bats of the same species, Nyctinomops laticaudatus (E. Geoffroy St.-Hilaire, 1805) (14.81% success). This report corroborates observations made in the Northern hemisphere, where bats are a dietary item of this falcon. Our findings are noteworthy because they reveal that the known natural predators of bats are few not only in Brazil but also worldwide.
Abstract in English:Scat-detection dogs have been used to locate feces of rare and elusive species across tropical biomes. However their detection efficiency in relation to human observers has rarely been evaluated. In this study, we evaluated the ability of a scat detection dog to locate feces in comparison with human researchers. Human researchers and a scat detection dog surveyed for deer (Mazama spp.) feces in dense ombrofilous Atlantic forest in the Paranapiacaba continuum, SP, Brazil. A controlled experiment was used to assess the maximum effective perpendicular distance from a transect search line that the dog could detect a Mazama spp fecal sample. Results from a linear regression model revealed that the maximum effective perpendicular distance from a transect search line that the dog could detect a scat was 7.2 m. The detection success from our surveys in the Atlantic forest was zero for humans and 0.15 samples/ha or 0.20 samples/km walked for the dog team. Our results demonstrated the importance of scat-detection dogs for non invasive sampling and provide data relevant for the design of future studies.