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Glyphosate-based herbicides are widely used in agriculture and are commonly found in water bodies. Roundup Original(®) (RO) contains an isopropylamine glyphosate (GLY) salt containing the surfactant POEA, while Roundup Transorb R(®) (RTR) contains a potassium salt of GLY with unknown surfactants. Both contain different compositions of so-called "inert" ingredients, more toxic than glyphosate. Amphibian tadpoles often experience variations in O2 availability in their aquatic habitats; an ability to tolerate hypoxia can condition their survival and fitness. We evaluated the impacts of sublethal concentrations of GLY (1 mg L(-1)), RO (1 mg L(-1) GLY a.e) and RTR (1 mg L(-1) GLY a.e) on metabolic rate (V·O2 - mLO2 Kg1 h(-1)) of bullfrog tadpoles during normoxia and graded hypoxia, and related this to morphology of their skin, their major site of gas exchange. In control (CT) V·O2 remained unaltered from normoxia until 40 mmHg, indicating a critical O2 tension between 40 and 20 mmHg. GLY significantly reduced V·O2, possibly due to epidermal hypertrophy, which increased O2 diffusion distance to O2 uptake. In contrast, RTR increased V·O2 during hypoxia, indicating an influence of "inert" compounds and surfactants. V·O2 of RO did not differ from CT, suggesting that any increase in V·O2 caused by exposure was antagonized by epidermal hypertrophy. Indeed, all herbicides caused marked alterations in skin morphology, with cell and epithelium wall presenting hyperplasia or hypertrophy and chromatid rupture. In summary, GLY, RO and RTR exert different effects in bullfrog tadpoles, in particular the surfactants and inert compounds appear to influence oxygen uptake.

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Biometric relationships are important to illustrate the growth of animals. When adjusted using nonlinear models, these relationships can provide important information that contributes to the improvement of breeding techniques. In this study, morphometric data as a function of weight obtained in four experiments involving bullfrog tadpoles were adjusted using Gompertz, Logistic, Von Bertalanffy and Brody nonlinear models and the best-fit model was determined. After fitting the parameters to the different models in each experiment, the models were compared based on confidence intervals ( = 0.05). The following criteria were used for selection of the best model: biological interpretation, residual mean square, coefficient of determination, graphic analysis, and number of iterations. Standard and total length data as a function of tadpole weight converged in the four models. The Logistic and Gompertz models had no biological interpretation for some datasets. The Brody model provided the lowest residual mean square and number of iterations for the variables studied in all experiments. The Brody relative growth rate (K) was lower for total length when compared to standard length, indicating a greater initial growth in standard length. The Brody model was the best to describe the growth in standard and total length of bullfrog tadpoles as a function of weight.(AU)

As relações biométricas são importantes para ilustrar o processo de crescimento dos animais. Estas, quando ajustadas a modelos não-lineares, podem revelar informações importantes para a melhoria das técnicas de criação. O conjunto de dados morfométricos em função do peso, de quatro experimentos com girinos de rã-touro, foram ajustados aos modelos não-lineares de Gompertz, Logístico, Von Bertalanffy e Brody, com objetivo de verificar o melhor ajuste. Após a adequação dos parâmetros para os diferentes modelos em cada experimento seguiu-se com a comparação dos mesmos, por meio dos intervalos de confiança ( = 0,05). Os critérios para selecionar os modelos foram: interpretação biológica, quadrado médio do resíduo, coeficiente de determinação, análise gráfica e o número de iterações. Os dados de comprimentos padrão e total em função do peso dos girinos convergiram nos quatro modelos. Os modelos Logístico e Gompertz não apresentaram interpretação biológica para alguns conjuntos de dados. O quadrado médio do resíduo e número de iterações em todos os experimentos e variáveis estudadas apresentaram os menores valores para o modelo de Brody. Os valores de K dos modelos de Brody para comprimento total, quando comparados ao padrão, apresentaram-se menores, indicando que os animais apresentaram um crescimento inicial maior em comprimento padrão.(AU)

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RESUMO

Biometric relationships are important to illustrate the growth of animals. When adjusted using nonlinear models, these relationships can provide important information that contributes to the improvement of breeding techniques. In this study, morphometric data as a function of weight obtained in four experiments involving bullfrog tadpoles were adjusted using Gompertz, Logistic, Von Bertalanffy and Brody nonlinear models and the best-fit model was determined. After fitting the parameters to the different models in each experiment, the models were compared based on confidence intervals ( = 0.05). The following criteria were used for selection of the best model: biological interpretation, residual mean square, coefficient of determination, graphic analysis, and number of iterations. Standard and total length data as a function of tadpole weight converged in the four models. The Logistic and Gompertz models had no biological interpretation for some datasets. The Brody model provided the lowest residual mean square and number of iterations for the variables studied in all experiments. The Brody relative growth rate (K) was lower for total length when compared to standard length, indicating a greater initial growth in standard length. The Brody model was the best to describe the growth in standard and total length of bullfrog tadpoles as a function of weight.

As relações biométricas são importantes para ilustrar o processo de crescimento dos animais. Estas, quando ajustadas a modelos não-lineares, podem revelar informações importantes para a melhoria das técnicas de criação. O conjunto de dados morfométricos em função do peso, de quatro experimentos com girinos de rã-touro, foram ajustados aos modelos não-lineares de Gompertz, Logístico, Von Bertalanffy e Brody, com objetivo de verificar o melhor ajuste. Após a adequação dos parâmetros para os diferentes modelos em cada experimento seguiu-se com a comparação dos mesmos, por meio dos intervalos de confiança ( = 0,05). Os critérios para selecionar os modelos foram: interpretação biológica, quadrado médio do resíduo, coeficiente de determinação, análise gráfica e o número de iterações. Os dados de comprimentos padrão e total em função do peso dos girinos convergiram nos quatro modelos. Os modelos Logístico e Gompertz não apresentaram interpretação biológica para alguns conjuntos de dados. O quadrado médio do resíduo e número de iterações em todos os experimentos e variáveis estudadas apresentaram os menores valores para o modelo de Brody. Os valores de K dos modelos de Brody para comprimento total, quando comparados ao padrão, apresentaram-se menores, indicando que os animais apresentaram um crescimento inicial maior em comprimento padrão.

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The aging process induces progressive and irreversible changes in the structural and functional organization of animals. The objective of this study was to evaluate the effects of aging on the structure and composition of the extracellular matrix of the arytenoid cartilage found in the larynx of male bullfrogs (Lithobates catesbeianus) kept in captivity for commercial purposes. Animals at 7, 180 and 1080 days post-metamorphosis (n=10/age) were euthanized and the cartilage was removed and processed for structural and biochemical analysis. For the structural analyses, cartilage sections were stained with picrosirius, toluidine blue, Weigert's resorcin-fuchsin and Von Kossa stain. The sections were also submitted to immunohistochemistry for detection of collagen types I and II. Other samples were processed for the ultrastructural and cytochemical analysis of proteoglycans. Histological sections were used to chondrocyte count. The number of positive stainings for proteoglycans was quantified by ultrastructural analysis. For quantification and analysis of glycosaminoglycans were used the dimethyl methylene blue and agarose gel electrophoresis methods. The chloramine T method was used for hydroxyproline quantification. At 7 days, basophilia was observed in the pericellular and territorial matrix, which decreased in the latter over the period studied. Collagen fibers were arranged perpendicular to the major axis of the cartilaginous plate and were thicker in older animals. Few calcification areas were observed at the periphery of the cartilage specimens in 1080-day-old animals. Type II collagen was present throughout the stroma at the different ages. Elastic fibers were found in the stroma and perichondrium and increased with age in the two regions. Proteoglycan staining significantly increased from 7 to 180 days and reduced at 1080 days. The amount of total glycosaminoglycans was higher in 180-day-old animals compared to the other ages, with marked presence of chondroitin- and dermatan-sulfate especially in this age. The content of hydroxyproline, which infers the total collagen concentration, was higher in 1080-day-old animals compared to the other ages. The results demonstrated the elastic nature of the arytenoid cartilage of L. catesbeianus and the occurrence of age-related changes in the structural organization and composition of the extracellular matrix. These changes may contribute to alter the function of the larynx in the animal during aging.

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The plantaris longus tendon (PLT) in bullfrog develops a fibrocartilage-like tissue in the area that is functionally subject to compressive forces. The aim of this study was to analyze the modifications of the pressure-bearing region in bullfrog PLT with different ages (7, 180, and 1,080 days after the end of metamorphosis) using histomorphometric, ultrastructural and biochemical methods. Weak basophilia and cells with a fibroblastic phenotype were observed in the compression region at 7 days of age. On the other hand, a large area of intense tissue basophilia associated with a chondroblast-like cell population was noted at the other ages. Collagen fibers exhibited a three-dimensional network-like arrangement at all ages. The number of connective tissue cells increased between 7 and 180 days of age and was reduced in older animals. The 180-day-old animals presented a well-developed pericellular matrix rich in proteoglycans. The mean diameter of collagen fibrils increased from 7 to 180 days and was the same at 1,080 days. Glycosaminoglycan content was higher in 7-day-old animals. A higher amount of hydroxyproline was observed at 180 and 1,080 days. The swelling test showed a significant increase of wet weight in 7-day-old animals. In conclusion, the alterations that occur in the pressure-bearing of bullfrog PLT are the result of physiological alterations of the animal with the maturation and aging.

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A identificação eletrônica apresenta-se como uma tecnologia inovadora na monitorização de animais, com uma série de vantagens quando comparada aos métodos tradicionais. Foram utilizados 30 reprodutores de rã-touro (Lithobates catesbeianus) com peso médio de 376,57 g. Os tratamentos foram correspondentes aos diferentes locais de implante: 1) região temporal e 2) região coxal. Os implantes na região temporal apresentaram uma distância de migração ≥10 mm, fato observado em 55,33% dos animais. No entanto, os microchips implantados na coxa migraram um trajeto muito inferior (≤2 mm), observado em 20% dos animais. O local mais indicado a receber o implante dos microchips foi a região coxal, por apresentar ótima aceitabilidade pelo animal e não desencadear inflamação ou rejeição. O implante ficou dentro de um limite não crítico de movimentação no corpo do animal.

The electronic identification presents itself as a new technology for the monitoring of animals, having a number of advantages compared to traditional methods. A total of 30 breeding bullfrog (Lithobates catesbeianus) with average weight of 376.57 g were used. The treatments were the different implant sites: 1) the temporal region and 2) coxal region. The implants had a temporal region of the migration distance ≥10 mm observed at 55.33% of the animals. However, the implanted microchip thigh migrated a path much less (≤2 mm) was observed in 20% of animals. The most suitable place to receive the implant of microchips was the coxal region, due to its overall acceptability by the animal and not triggers inflammation or rejection, getting within a limit not critical movement in the animal body.

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RESUMO

A identificação eletrônica apresenta-se como uma tecnologia inovadora na monitorização de animais, com uma série de vantagens quando comparada aos métodos tradicionais. Foram utilizados 30 reprodutores de rã-touro (Lithobates catesbeianus) com peso médio de 376,57 g. Os tratamentos foram correspondentes aos diferentes locais de implante: 1) região temporal e 2) região coxal. Os implantes na região temporal apresentaram uma distância de migração ≥10 mm, fato observado em 55,33% dos animais. No entanto, os microchips implantados na coxa migraram um trajeto muito inferior (≤2 mm), observado em 20% dos animais. O local mais indicado a receber o implante dos microchips foi a região coxal, por apresentar ótima aceitabilidade pelo animal e não desencadear inflamação ou rejeição. O implante ficou dentro de um limite não crítico de movimentação no corpo do animal. (AU)

The electronic identification presents itself as a new technology for the monitoring of animals, having a number of advantages compared to traditional methods. A total of 30 breeding bullfrog (Lithobates catesbeianus) with average weight of 376.57 g were used. The treatments were the different implant sites: 1) the temporal region and 2) coxal region. The implants had a temporal region of the migration distance ≥10 mm observed at 55.33% of the animals. However, the implanted microchip thigh migrated a path much less (≤2 mm) was observed in 20% of animals. The most suitable place to receive the implant of microchips was the coxal region, due to its overall acceptability by the animal and not triggers inflammation or rejection, getting within a limit not critical movement in the animal body. (AU)

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The bullfrog (Lithobates catesbeianus) is an exotic animal that adapted perfectly to the climatic conditions of Brazil after introduction in the country. These climatic conditions favor the reproduction and fattening of bullfrogs. However, the development of the bullfrog is significantly reduced in colder regions because low temperatures affect the secretion of gonadotropins and change the sensitivity of the germinal epithelium to gonadotropic hormones. Thus, the temperature and photoperiod are abiotic factors that influence the life cycle of this species, especially with regard to reproduction. Samples from different regions of the oviducts (the infundibulum, magnum, and isthmus) of 9 bullfrogs were collected in the different seasons of the year. The samples were fixed and processed for analysis with scanning and transmission electron microscopy. A comparison of the morphology of the oviducts collected during different seasonal periods suggests that the frogs have greater reproductive potential in the spring due to the development of the structures related to the oviduct, presence of developed cilia, and electron-dense granules. However, seasonal changes were noted in the animal throughout the year in preparation for reproduction during the spring and summer.

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La superficie dorsal de la lengua de la rana toro, Rana catesbeiana, presenta un epitelio simple cilíndrico, constituido por células caliciformes y raras células ciliadas. El dorso de la lengua posee numerosas papilas filiformes y algunas fungiformes. Las primeras poseen un epitelio simple cilíndrico, con células secretoras, mientras que las segundas poseen en la región apical, un disco sensorial con epitelio estratificado cilíndrico, con células basales, periféricas, glandulares y receptoras. A lo largo del dorso de la lengua existen numerosas glándulas tubulares, que penetran en profundidad, entremezclándose con las fibras musculares. El epitelio glandular es simple cilíndrico, con células secretoras y de sostén. Las primeras son las únicas en la base de la glándula y las segundas solo se encuentran en número escaso en el tercio superior. La superficie ventral de la lengua posee un epitelio estratificado, con células caliciformes y, entre éstas, células ciliadas. La morfometría de las glándulas mostró que son más cortas en la región anterior de la lengua (330 um) que en la región posterior (450 um). Las células secretoras de las glándulas linguales anteriores son menores (1457,7 um3) que en las posteriores (2645,9 um3). Lo mismo ocurre con los núcleos celulares: 130,0 um3 en las glándulas anteriores y 202,3 um3 en las posteriores. Las células secretoras de las glándulas linguales sintetizan producto rico en proteínas y mucopolisacáridos neutros, pudiendo caracterizarse como seromucoso. Las células caliciformes de las superficies dorsal y ventral secretan proteínas y mucopolisacáridos neutros, clasificándose como del tipo G1, mientras que las células de sostén de las glándulas superficiales de las papilas fungiformes secretan moco rico en mucopolisacáridos neutros, sulfomucinas y sialomucinas.

The dorsal surface of the tongue of the bullfrog, Rana catesbeiana, has simple columnar epithelium with a few ciliated cells and goblet cells. The entire surface is covered with numerous filiform papillae and few fungiform. Filiform papillae have a simple columnar epithelium with secretory cells, while the fungiform have a sensory disc on their upper surface the lined by a stratified columnar epithelium with basal, peripheral, glandular and receptor cells. Over the dorsal lingual surface there are numerous winding tubular glands, which penetrate deeply into the muscle of the tongue, mingling with the fibers. The gland epithelium is cylindrical with secretory and supporting cells. The first are absolute on the basis of the gland and the latter are rare in the upper third. The ventral surface of the tongue is lined by a stratified epithelium, with the presence of goblet cells, with ciliated cells among them. Morphometrically, lingual glands varies in length, according to their location: shorter in the anterior region of the tongue (330 um) than in the posterior region (450 um). Secretory cells of the anterior lingual glands are smaller (1457.7 mm3) than the posterior ones (2645.9 um3). The same can be said of the cell nuclei, 130.0 um3 for the anterior glands and 202.3 um3 for the posterior ones. Secretory cells of the lingual glands contain substances rich in protein and neutral mucopolysaccharides, which characterize the seromucous type. Goblet cells of the dorsal and ventral surface epithelia secrete neutral mucopolysaccharides and proteins, and can be characterized as type G1 cells, and the supporting cells of the superficial glands of the fungiform papillae secrete a mucus rich in neutral mucopolysaccharides, sulfomucins and sialomucins.

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Amphibians represent the first phylogenetic group to possess hematopoietic bone marrow. However, adult amphibian hematopoiesis has only been described in a few species and with conflicting data. Bone marrow, kidney, spleen, liver, gut, stomach, lung, tegument, and heart were therefore collected from adult Lithobates catesbeianus and investigated by light microscopy and immunohistochemical methods under confocal laser microscopy. Our study demonstrated active hematopoiesis in the bone marrow of vertebrae, femur, and fingers and in the kidney, but no hematopoietic activity inside other organs including the spleen and liver. Blood cells were identified as a heterogeneous cell population constituted by heterophils, basophils, eosinophils, monocytes, erythrocytic cells, lymphocytes, and their precursors. Cellular islets of the thrombocytic lineage occurred near sinusoids of the bone marrow. Antibodies against CD34, CD117, stem cell antigen, erythropoietin receptor, and the receptor for granulocyte colony-stimulating factor identified some cell populations, and some circulating immature cells were seen in the bloodstream. Thus, on the basis of these phylogenetic features, we propose that L. catesbeianus can be used as an important model for hematopoietic studies, since this anuran exhibits hematopoiesis characteristics both of lower vertebrates (renal hematopoiesis) and of higher vertebrates (bone marrow hematopoiesis).

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Collagen structural organization plays an important role in the mechanical property of the vertebrate integument. Bufo ictericus and Rana catesbeiana integument was investigated by light microscopy and laser confocal microscopy. Collagenous elements of the dermis were statistical analyzed. The integument is formed by the keratinized squamous stratified epidermis supported by the dermis that is subdivided into the spongious layer with a loose arrangement, and the compact layer formed by collagenous fibers arranged compactly in a criss-crossed manner. Thick collagenous columns have a perpendicular trajectory, and are formed by the assembling of alternating collagenous lamellae in both animals. Short intercolumns of collagenous fibrils connecting collagenous lamellae obliquely or transversally are observed in R. catesbeiana dorsal integument. The present study provides evidences that B. ictericus and R. catesbeiana integument has well-organized compact dermis, constituted by collagenous lamellae in a plywood manner. The integument organization is in contrast to the literature in some aspects. This dermal arrangement is important to the biomechanical property of both anuran integuments.

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This is the first description of an in vivo potentiation phenomenon associated to spreading depression (SD) in the frog optic tectum. Field potential responses electrically-elicited from the optic tract and recorded in the optic tectum disappeared during KCl-elicited SD and recovered 10-20 min thereafter. Post-SD responses reached amplitudes 10-30% higher than their pre-SD values (P<0.05), indicating a potentiation effect. Current source density analysis of the tectal depth profiles of field-potential responses, as well as the calculation of the post-SD intratectal conductance changes, also supported the potentiation phenomenon. This in vivo potentiation lasted for 40-90 min, suggesting a post-SD enhancement of synaptic transmission, which may be important in understanding mechanisms of brain disfunctions like epilepsy.

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Amphibian eyes play an important role in vision and in several physiological processes, such as food capture and breathing. To maintain the integrity of the eyeball there is a unique cuplike hyaline cartilage as a supporting tissue. In Bufo ictericus and Rana catesbeiana the cartilage layer is located between the retina and the choroids, being designated as choroidal cartilage, important to visual performance. On the retinal surface, there is no perichondrium, and the pigmented epithelium exhibits an intimate relationship to the cartilage layer.

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Spermatogenesis and steroidogenesis undergo seasonal variations during the reproductive cycle in amphibians. Testicular morphological and morphometric seasonal variations as well as interstitial lipidic inclusions and intralobular glycoconjugates were evaluated during seasonal cycle of Rana catesbeiana. Testes of frogs collected during the annual seasons were weighed for calculation of GSI (Gonadosomatic index). Seminiferous lobule diameters (DSL) and volume densities of seminiferous lobules (VvSL), excretory ducts (VvED), and interstitial tissue (VvIT) were analyzed. Semithin sections were submitted to Periodic Acid-Schiff (PAS) and Alcian Blue (AB) methods for detection of glycoconjugates, while lipidic inclusions were detected by Sudan Black B. GSI showed no significant variations during the year. Since VvED and VvIT increased significantly during summer and were inversely proportional to VvSL, a compensatory effect between the testicular compartments may be related to the maintenance of GSI. During autumn/winter, larger lobular diameters were observed in comparison to spring/summer when spermiogenesis and spermiation were commonly observed. The increased VvIT and the numerous lipidic inclusions in the interstitial cells during summer suggest a relationship between spermiogenesis and steroidogenesis. Besides the structural stability variations occurring in the IT and SL, a possible paracrine interaction between ED and IT should be also involved in the IT development during summer. The presence of PAS and AB-positive globular structures were observed in the seminiferous lobules and excretory ducts. These structures containing acid glycoconjugates appear to be Sertoli cell apical portions, which are accumulated in the lumen of the seminiferous lobules mainly during spermiation.

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The deposition of enamel is marked by the formation of growth lines, which reflect incremental growth. Although periodic markings have been observed in enamel of non-mammalian vertebrates, the cross-striation interval and the pattern of enamel deposition have not been formally investigated. Here a structural study was made of the enamel in four non-mammalian vertebrates, with emphasis on periodic markings. Teeth from Rana catesbeiana, Tropidurus torquatus, Caiman crocodilus and a Canadian carnosaur were analysed. Enamel of T. torquatus and R. castebeiana was aprismatic; that of C. crocodilus and the carnosaur was formed by large, prism-like structures. Conspicuous incremental lines were observed in the enamel of the three living species, which presented a cross-striation repeat smaller than the prism cross-striations of mammalian enamel. Incremental lines of carnosaur enamel had a mean repeat interval similar to that of mammalian prism cross-striations. As metabolic activity in ectotherms is influenced by environmental conditions, the analysis of incremental markings of enamel is a potentially valuable source of information in the study of living and fossil reptiles and amphibians.

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Elastic system components have been described in the pressure-bearing tendon of the bullfrog, Rana catesbeiana, as a result of histochemical tests and transmission and scanning electron microscopy. The tension region was shown to possess microfibril bundles, some of which exhibited central deposits of amorphous material. The use of ANS-butanol plus fluorescence microscopy enormously facilitated the identification of elastic system components in both tension and compression regions of the frog tendon. The compression region exhibited pre-elastic and mature elastic fibers, which were shown to be associated with the surface of the convoluted collagen bundles. Thin fibrils were observed in the compression region after ANS treatment. The visceral paratenon had an increased number of elastic fibers located between the collagen bundles and close to the cells. Congo red plus polarization microscopy failed to impart birefringence to the elastic fibers, but they could be identified by their intense staining and isotropic appearance against the bright background of birefringent collagen fibers. SEM demonstrated the three-dimensional aspects of the elastic fibers. They are composed of fibrils of a sinuous nature. The use of ruthenium red in the fixative allowed for the observation of an intimate association of proteoglycan granules with the microfibril bundles. The elastic components identified in the pressure-bearing tendon are assumed to be important for the tissue supramolecular organization, especially in the maintenance of the convoluted state of the collagen fibers in the compression region and their crimp morphology in the tension region. The elastic system must also play an important role in the restoration of the resting shape of the tendon after the deformation achieved during mechanical stimulation.

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Se estudió la sensibilidad de la vía auditiva a través del registro de los potenciales auditivos de tallo cerebral en 10 anfibios sanos de la especie Rana catesbiana. Las respuestas auditivas se efectuaron a 70, 50, 40 y 30 dB NA, en dos grupos de diferente peso. El primero de 17 a 27 gr y el otro grupo de 36 a 86.5 gr, los electrodos fueron insertados subcutáneamente y la estimulación fue por clicks en campo libre dentro de una cámara sonoamortiguada. A 70 dB las respuestas fueron de dos ondas en los primeros milisegundos, a 50 dB la onda II se separó en dos subcomponentes (IIa y IIb). El umbral electrofisiológico se estableció en 40 dB

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The fiber distribution and ultrastructure in the plantaris longus pressure-bearing tendon of the bullfrog were investigated. The tension region of the tendon showed a predominant parallel distribution of collagen fibers, but three main zones with different crimp parameters were identified with the use of the polarizing microscope. The compression region showed collagen fibers with aspects of disaggregation and were composed of disperse and undulating fibrils. These collagen fibers establish a three-dimensional network but showed a preferential distribution in planes disposed perpendicularly to the tendon's main axis. It is assumed that the convoluted and disaggregated collagen fibers must be distended before exerting any reinforcement on the tissue and that this only occurs after a great deformation of the tendon. Groups of 5-6 fibrils not associated in fibers are also dispersed in the compression region. The tissue is assumed to have a highly viscous fluid nature allowing for the deformation needed for collagen fibrils to reinforce the tendon structure. The convoluted and crimped structure of collagen fibers would be especially useful when the tendon is submitted to the sudden and strong mechanical loading expected to occur during jumping and to provide the tendon with the capacity of great functional deformability necessary for the high amplitude of feet movements attained on jumping and swimming.

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Estudou-se 96 amostras de carnes de räs procedentes de abatedouros sob Inspeçäo Sanitária e sem Inspeçäo Sanitária de diferentes estados do Brasil, com isolamento de 61 bolores e 240 leveduras.As leveduras foram identificadas em 10 gêneros diferentes, distribuídos em 28 espécies.Resalta-se a ocorrência de Canddida albicans e Candida tropicalis pelo potencial patogênico e por näo serem de ocorrência comum em carnese derivados.Osresultados indicam que a microbiota fúngica em carnes de räs é predominantemente composta de leveduras isoladas de acordo com os tipos de abatedouros estudados näo foram, estatisticamente, significativas.

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