Frugivory by toucans (Ramphastidae) at two altitudes in the Atlantic Forest of Brazil

Toucans are prominent components of the tropical American avifauna. Although these birds are very conspicuous, there are few ecological studies focusing on them. In this study, the diets of four sympatric toucans (Ramphastos vitellinus, R. dicolorus, Selenidera maculirostris, and Baillonius bailloni) were assessed by recording feeding bouts at two altitudes in the Atlantic Forest of southeast Brazil. Our results show that toucans are predominantly frugivorous birds (96.5% of the 289 feeding bouts were on fruits). In the lowlands (70 m elev.), only fruits (48 species, 27 families) were recorded, while in the highlands (700 m elev.), toucans were observed feeding on fruits (25 species, 22 families), flowers, leaves, and insects. Non-fruit items were recorded only in the highlands, most of them eaten by B. bailloni. Cecropia glaziovii and Euterpe edulis, two abundant plants in the highland and lowland sites, respectively, and Virola oleifera, a plant that produces lipid-rich arillate fruits, were eaten heavily by the toucans. The number of feeding bouts recorded for R. vitellinus in the lowlands was positively correlated with lipid content of the fruits eaten. The diameters of fruits eaten by toucans varied greatly (range = 0.4-25.0 mm). While the large Ramphastos species not only ate tiny fruits (e.g., Hyeronima alchorneoides) but also large ones (e.g., Virola gardneri), the toucanets ate piecemeal the large fruits that exceeded their gape width, suggesting that gape size did not limit the use of any fruit by the toucans at our study sites.

Energetic and physiological correlates of prey handling and ingestion in lizards and snakes

In this review, we summarize the energetic and physiological correlates of prey handling and ingestion in lizards and snakes. There were marked differences in the magnitude of aerobic metabolism during prey handling and ingestion between these two groups, although they show a similar pattern of variation as a function of relative prey mass. For lizards, the magnitude of aerobic metabolism during prey handling and ingestion also varied as a function of morphological specializations for a particular habitat, prey type, and behavior. For snakes, interspecific differences in aerobic metabolism during prey handling seem to be correlated with adaptations for prey capture (venom injection vs. constriction). During ingestion by snakes, differences in aerobic metabolism might be due to differences in cranial morphology, although allometric effects might be a potentially confounded effect. Anaerobic metabolism is used for prey handling and ingestion, but its relative contribution to total ATP production seems to be more pronounced in snakes than in lizards. The energetic costs of prey handling and ingestion are trivial for both groups and cannot be used to predict patterns of prey-size selection. For lizards, it seems that morphological and ecological factors set the constraints on prey handling and ingestion. For snakes, besides these two factors, the capacity of the cardio-respiratory system may also be an important factor constraining the capacity for prey handling and ingestion. © 2001 Elsevier B.V.

Protein requirements in larvae and adults of Scaptotrigona postica (Hymenoptera: Apidia, Meliponinae): Midgut proteolytic activity and pollen digestion

The number and degree of digestion of pollen grains in the midgut and rectum, the midgut proteolytic activity and the time of pollen grain passage through the digestive tract in the stingless bee Scaptotrigona postica (Latreille) have been analyzed. The results show similar protein requirements among larvae, nurse bees and queens, as well as between forager bees and old males, but these requirements are higher in individuals from the former groups than in those from the latter. Although protein requirements have been demonstrated to vary according to a bee's activity in the colony, they are similar among bees from different castes or sexes. These changes in feeding behavior are related to the bee's function and to less competition for nourishment among individuals of the colony. It is also noted that pollen grains took between 6 and 28 h to pass through the digestive tract. Pollen grains are irregularly accumulated in the various regions of the midgut, which may reflect functional differentiation throughout the midgut. © 2001 Elsevier B.V.

Morphology and histochemistry of the hyolingual apparatus in chameleons

We reexamined the morphological and functional properties of the hyoid, the tongue pad, and hyolingual musculature in chameleons. Dissections and histological sections indicated the presence of five distinctly individualized pairs of intrinsic tongue muscles. An analysis of the histochemical properties of the system revealed only two fiber types in the hyolingual muscles: fast glycolytic and fast oxidative glycolytic fibers. In accordance with this observation, motor-endplate staining showed that all endplates are of the en-plaque type. All muscles show relatively short fibers and large numbers of motor endplates, indicating a large potential for fine muscular control. The connective tissue sheet surrounding the entoglossal process contains elastin fibers at its periphery, allowing for elastic recoil of the hyolingual system after prey capture. The connective tissue sheets surrounding the m. accelerator and m. hyoglossus were examined under polarized light. The collagen fibers in the accelerator epimysium are configured in a crossed helical array that will facilitate limited muscle elongation. The microstructure of the tongue pad as revealed by SEM showed decreased adhesive properties, indicating a change in the prey prehension mechanics in chameleons compared to agamid or iguanid lizards. These findings provide the basis for further experimental analysis of the hyolingual system. © 2001 Wiley-Liss, Inc.

Composição corporal e índices biométricos do pacu, Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes, Characidae) submetido a ciclos alternados de restrição alimentar e realimentação

The present paper evaluated, through hepatosomatic/mesenteric fat indexes and body composition, the pacu energy utilization when submitted to alternated food restriction/refeeding cycles during the growout period. Juveniles were distributed in three pounds and submitted to different feeding programs: A (ad libitum daily feeding), B (4-week feeding restriction and 9-week refeeding) and C (6-week feeding restrictions and 7-week refeeding), totaling 13 weeks for each cycle (4 experimental cycles). At the end of the periods, fish were sampled to obtain biometrics and biochemical data. The results showed that, during the first two cycles, C treatment obtained the best compensatory growth. Carcass lipid and water contents were inversely related, with body fat decrease. Fishes under B and C treatment during food restriction utilized liver and mesentery energy stores. These parameters were re-established in the refeeding phase, in all cycles.

Relação peso-comprimento e fator de condição para Cichla cf. ocellaris e Cichla monoculus (Perciformes, Cichlidae) no reservatório de Volta Grande, Rio Grande - MG/SP

The aim of this paper was to analyze the length-weight relationship and the condition factor of two species of cichlids (Cichla cf. ocellaris and Cichla monoculus) (Perciformes, Cichlidae) that were inducted in Volta Grande Reservoir, Rio Grande. There was no difference in the length-weight relationship between the sexes for Cichla cf. ocellaris and Cichla monoculus. The allometric condition factor showed a fall in the spring and another smaller one in the winter. It happens when these fishes change their feeding activity. In the spring all the reproductive behavior are developed and, in the winter, there is a shortage of prey. The variation of the relative condition factor followed the variation of the allometric condition factor due to the low contribution of the gonads weight and the small amount of accumulated fat in the total weight. The length distribution, length-weight relationship and condition factor of these fishes vary in accordance with the time of introduction into the reservoir, the characteristics of the ecosystem as well as the interactions among the species at these sites.

O lambari Astyanax altiparanae (Characidae) pode ser um dispersor de sementes?

This work characterized the feeding of Astyanax altiparanae in the sub-basin of Corumbataí river and in the basin of Jacaré-pepira river with a focus on the ingestion of Croton urucurana seeds. The food items of Astyanax altiparanae were, in decreasing APD (Alimentary Preference Degree) order: allochthonous insects, allochthonous plant material, Croton urucurana seeds, autochthonous insects, sediments, autochthonous plant material, scales, oocytes and arachnidans. Croton urucurana seeds occurred during the summer, in the flood period. Lambari, Astyanax altiparanae, could be a secondary disperser of Croton urucurana seeds, however, the intensity and effectiveness of this dispersion may be still investigated.

Two Digestive Trypsins Occur in Three Species of Neotropical Anophelines

Trypsin activity increases in the midgut of Anopheles aquasalis, Anopheles albitarsis, and Anopheles darlingi after a bloodmeal. The activity returns to basal levels at the time the blood is completely digested. Affinity chromatography, reversed-phase high performance liquid chromatography (HPLC), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used to sequentially purify the mosquito trypsins found in the midguts at 24 h after feeding. Amino-terminal sequencing of the purified trypsins showed the occurrence of two distinct trypsins in the midgut of each of the mosquitoes studied. The sequences obtained are similar to those of the trypsins of other hematophagous insects.

Fruit and seed exploitation by small rodents of the Brazilian Atlantic forest

In the Brazilian Atlantic forest (BAF) there are at least 57 rodent species and most of them are considered omnivorous. These species feed, more or less frequently, on fruits and seeds. Nevertheless the potential role of each species as frugivorous, seed predator or seed disperser is still unclear. In the present study we analyzed patterns of fruit and seed exploitation by eight small rodent species from an Atlantic Forest site. We offered to captive animals fruits of 30 plant species (23 genera, 15 families). After 48 h we recorded consumption patterns of pulp/aril and seed. Rodent species differed in their patterns of fruit and seed exploitation. The smallest species, Akodon serrensis, Oligoryzomys nigripes, and Wilfredomys pictipes (body size range : 26-45 g), and also the medium-sized Oecomys aff. concolor (84 g) fed mainly on pulp and also on small to medium-sized seeds (< 10 mm diameter). The medium-sized rodent, Oryzomys russatus (91 g) fed on pulp and also on seeds with diameter ≤ 15 mm. Thus larger seeds remain intact after being manipulated by such species. The medium-sized Delomys dorsalis (72 g) and the larger Trinomys iheringi (274 g) and Nectomys squamipes (253 g) form a third group, which consumed both fruit and seed of most species independent of their size. These later two species and also O. russatus are probably the main seed predators in the rodent community of the BAF.

Características hematológicas, bioquímicas e biométricas de Piaractus mesopotamicus Holmberg, 1887 (Osteichthyes: Characidae) oriundos de cultivo intensivo

Hematological characteristics are important tools for diagnosis and prognostic features in fish population and they contribute to the comprehension of comparative physiology, phylogenetic relation, food habit and other ecological parameters. Red blood cell count (RBC), white blood cell count (WBC), thrombocytes counts, glucose, cortisol, hepatosomatic and splenosomatic relation were evaluated in Piaractus mesopotamicus. The values of hepatosomatic relation varied from 0.67% to 2.79% and splenosomatic relation from 0.011% to 0.108%. RBC 1.870 to 4.590 × 106/μL, hemoglobin concentration 5.7 to 12.1g/dL, haematocrit 24.0% to 40.0%, mean corpuscular volume 98.0 to 174.0 fL, mean corpuscular haemoglobin concentration 19.1 to 34.2g/dL, glucose 40.6 to 89.2mg/dL and cortisol 4.73 to 110.5ng/dL The number of total thrombocytes was 12,160.0 to 89,280.0/μL and WBC 2,019.0 to 47,473.0/μL. Differential count of leucocytes showed 54.1% limphocytes, 10.9% neutrophils, 10.3% monocytes, 9.9% PAS-positive granular leukocytes (PAS-GL), 6.7% eosinophils, 0.3% basophils and 7.8% immature leucocytes. Variation of these haematological characteristics in the same fish species was observed, being considered as the normal variation in the fish concerned. Hence it is incorrect to assume that biological characteristics in fishes are distributed normally.

Differential fruit consumption of two Melastomataceae by birds in Serra da Mantiqueira, southeastern Brazil

In this study we report on the consumption of two syntopic Melastomataceae species by birds in a lower montane forest in Monte Verde, southeastern Brazil. The species of frugivores were identified and characterized by their methods of capture and consumption of fruits. We also provide information on abundance, phenology of plants and fruit characteristics of the two Melastomataceae species. The 13 observed species of birds formed two statistically distinct frugivorous groups with taxonomic and behavioral differences. Five of seven bird species that fed on L. aff. sublanata fruits belong to the subfamily Thraupinae and most fruits were mashed before swallowed. Four of the eight bird species that visited M. cinerascens belong to the subfamily Turdinae and all fruits were swallowed whole. Only two bird species were common visitors of both Melastomataceae species. Our findings show that fruits of the two Melastomataceae species with similar morphological characteristics were exploited differently by frugivorours birds.

Frugivoria por aves em Cytharexyllum myrianthum cham (Verbenaceae) em áreas de pastagens de Campinas, SP

Isolated trees in pastures are now often, due to increasing devastation of forested areas, important feeding places for migratory or generalist birds. These trees serve both as food sources and as deposition sites for seeds from fruits consumed in neighboring areas. The objective of this study was to identify the avian consumers of the fruits of Cytharexyllum myrianthum trees in open pastures and describe their feeding behavior and how it influences seed dispersion. Forty two hours of observations included 198 feeding bouts of nine bird species. Turdus leucomelas (Muscicapidae) was the main consumer (28% of fruit consumption), swallowing the entire fruit. Next, was Tyrannus melancholicus (Tyrannidae, 23%), which may be the most efficient seed disperser of C. myrianthum because it regurgitates the seeds on sites far from the parent tree.

Uso do grau de preferência alimentar para a caracterizaç ão da alimentação de peixes na APA de São Pedro e Analândia

We studied feeding habits of four fish species in two watershed at APA - Área de Proteção Ambiental (Area of Environmental Protection) in São Pedro and Analândia, State of São Paulo, southeastern Brazil. Feeding Preference Degree (FPD) was used to demonstrate the importance of each food item for the species of both basins. Feeding habits of both species of lambari was variable. The allochtonous items such as insects, autochtonous items, and vegetal material were very important, characterizing omnivory. The bagre (Rhamdia quelen) fed mainly on insects at the Jacaré-pepira Basin and also on fishes at the Corumbataí basin. The cascudo Hypostomus strigaticeps ingested autochtonous vegetal material and sediments at both basins.

Assessment of the diet of 0- to 6-year-old children in municipal schools in a Brazilian city

Diet control is one of the important factors in the prevention of dental caries because food functions as substratum for fermentation and, consequently, for the formation of the organic acids that demineralize the tooth surface. This study aims to descriptively assess school diet and the associated caries-preventive methods applied to children in all municipal nursery schools of a Brazilian city (Aragatuba/SP). For this, a questionnaire with open and closed questions was used. The results showed that all schools serve school meal, which is composed mainly of sugar, carbohydrates, and proteins. The students enjoy the meal very much because for most of them, the meal served at school is the only source of food. It was observed that 90% of the schools offer other kinds of food besides the main school meal. The snacks served such as cakes, white hominy, and milk fudge are composed of sweet and highly cariogenic foods. It was also verified that in 13.30% of the schools, the daily supervised dental hygiene, an important procedure that should not be neglected, is not carried out. This procedure introduces the children to healthy habits that are added to those acquired in the family environment. It was concluded that the school diet is potentially cariogenic and, in association with the lack of daily dental hygiene, this potential may become even higher.

Prevalência de sobrepeso e obesidade em escolares de alto nível socioeconômico em Londrina, Paraná, Brasil

Objective: To verify the prevalence of overweight and obesity in 7 to 10 year old schoolchildren of both sexes and high socioeconomic level. Methods: Five hundred and eleven schoolchildren (274 boys and 237 girls) were submitted to anthropometrical measurements of body mass, stature and subscapular and triceps skin-fold thickness. Body mass indexes ≥85th percentile and <95th percentile were used to determine overweight, whereas body mass indexes ≥95th percentile were adopted as indicators of obesity. The socioeconomic level was established based on information obtained from a questionnaire, considering the degree of education of the parents and the familiar consumables. Results: The total prevalence for overweight was 19.7% for the boys and 17.3% for the girls, with no significant differences amongst ages and sexes (p>0.05). On the other hand, the prevalence for obesity in the boys and girls was 17.5% and 9.3%, respectively, with significant differences between the sexes at 9 years (p<0.01) and 10 years (p<0.05) of age, as well as amongst the entire group of ages (p<0.01). Conclusion: The results indicated a high prevalence ratio for overweight (∼19%) and obesity (∼14%), much greater than the average for the 7-10 year old Brazilian population. Therefore, different from that observed in developed countries, a high socioeconomic level seems to negatively affect the prevalence for overweight and obesity, increasing the risk of the precocious development of metabolic dysfunctions.