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Plastic microfibers (PMFs) are emerging pollutants widely distributed in the environment. In the early 2020s, the need for personal protection due to the COVID-19 pandemic led to increased consumption of plastic materials (e.g., facemasks and gloves) and ultimately to increased plastic pollution, especially by PMFs. The PMFs present in the environment may be released in this form (primary particles) or in larger materials, that will release them as a result of environmental conditions. Although a considerable number of studies have been addressing the effects of microplastics, most of them studied round particles, with fewer studies focusing on PMFs. Thus, the current study aimed to summarize and critically discuss the available data concerning the ecotoxicological impact of PMFs on aquatic organisms. Aquatic organisms exposed to PMFs showed accumulation, mainly in the digestive tract, and several toxic effects, such as DNA damage, physiological alterations, digestive damage and even mortality, suggesting that PMFs can pose a risk for the health of aquatic organisms. The PMFs induced toxicity to aquatic invertebrate and vertebrate organisms depends on size, shape, chemical association and composition of fibers. Regarding other size range (nm) of plastic fibers, the literature review highlighted a knowledge gap in terms of the effects of plastic nanofibers on aquatic organisms. There is a knowledge gap in terms of the interaction and modes of action of PMFs associated with other pollutants. In addition, studies addressing effects at different trophic levels as well as the use of other biological models should be considered. Overall, research gaps and recommendations for future research and trends considering the environmental impact of the COVID-19 pandemic are presented.

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The ecotoxicological risk to vertebrates posed by zinc oxide nanoparticles (ZnO NPs) is still poorly understood, especially in animals with a biphasic life cycle, which have aquatic and terrestrial phases, such as amphibians. In the present study, we investigated whether acute exposure (7 days) to ZnO NPs and zinc chloride (ZnCl2) at three environmentally relevant concentrations (0.1, 1.0, and 10 mg L-1) induces changes in the morphology, chondrocranium, and behavior of the tadpoles of Lithobates catesbeianus (Anura: Ranidae). Tadpoles exposed to both forms of Zn did not undergo any morphological or behavioral changes at the lowest concentrations (0.1 and 1.0 mg L-1). However, the animals exposed to the highest concentration (10 mg L-1) lacked oral disc structures, were smaller in size, had a longer tail, and presented changes in the position and coiling of the intestine and malformations of the chondrocranium in comparison with the control group. This indicates that ZnO NPs and ZnCl2 altered the development of the tadpoles, causing delays in their metamorphosis and even reducing individual fitness. The tadpoles exposed to both forms of Zn at 10 mg L-1 also had reduced mobility, especially in the presence of conspecifics. Based on these findings, we emphasize the importance of studying morphological, skeletal, and behavioral biomarkers to evaluate the toxic effects of metal-based nanoparticles in amphibians.

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The use of benzodiazepines (BZDs) during pregnancy, especially alprazolam, is common and its impact on the fetal neural tissue is not known. In this sense, the present study aimed to investigate the effects of prenatal treatment with alprazolam on the cerebellum of Wistar rat pups. Thirty animals (24 females and six males, CEUA protocol 014/17) were separated into pairs for copulation. Females were divided into three groups: Control (CT), treatment 1 (T1, 1.25 mg per animal), and treatment 2, which is an overdose (T2, 30 mg per animal). Alprazolam was administered 10 days before copulation and throughout pregnancy. We evaluated the number and weight of pups and the macroscopic changes in the brain. Eight neonates (n = 8) from each group were used in the following analyses: Cellular and chromatin density, gliosis, synaptic density, inflammation, and oxidative stress. The results showed no significant differences regarding the number of pups, body weight, and macroscopic changes. The morphological study focused on the external granular layer (EGL) that is presented only in the immature cerebellum. Here, we detected more cells after alprazolam treatment; the T2 group showed large nuclei and some pyknotic nuclei; also, both treated groups presented an increase in the euchromatin density compared with the control. The molecular and biochemical analyses used the total protein extract of the entire cerebellum and showed an increased expression of Iba-1 and NF-κBp65 but without indication of inflammation or degeneration in the T1 group. Overdose of alprazolam presented an increased level of oxidative degradation of lipids. The treatment with alprazolam during pregnancy involved cellular and molecular changes in the immature cerebellum.

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Iron oxide nanoparticles (IONPs) are used in several medical and environmental applications, but their mechanism of action and hazardous effects to early developmental stages of fish remain unknown. Thus, the present study aimed to assess the developmental toxicity of citrate-functionalized IONPs (γ-Fe2O3 NPs), in comparison with its dissolved counterpart, in zebrafish (Danio rerio) after static and semi-static exposure. Embryos were exposed to environmental concentrations of both iron forms (0.3, 0.6, 1.25, 2.5, 5 and 10 mg L-1) during 144 h, jointly with negative control group. The interaction and distribution of both Fe forms on the external chorion and larvae surface were measured, following by multiple biomarker assessment (mortality, hatching rate, neurotoxicity, cardiotoxicity, morphological alterations and 12 morphometrics parameters). Results showed that IONPs were mainly accumulated on the zebrafish chorion, and in the digestive system and liver of the larvae. Although the IONPs induced low embryotoxicity compared to iron ions in both exposure conditions, these nanomaterials induced sublethal effects, mainly cardiotoxic effects (reduced heartbeat, blood accumulation in the heart and pericardial edema). The semi-static exposure to both iron forms induced high embryotoxicity compared to static exposure, indicating that the nanotoxicity to early developmental stages of fish depends on the exposure system. This is the first study concerning the role of the exposure condition on the developmental toxicity of IONPs on fish species.

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Despite the damaging effects of pesticides glyphosate (Gly), atrazine (Atra) and fipronil (Fip) on different organisms, the mutagenic, genotoxic and morphotoxic potential of testudine erythrocytes in freshwater remains unknown. Thus, the aim of the present study is to assess the toxicological potential of these compounds in Podocnemis expansa (Amazonian turtles) neonates from eggs artificially incubated in substrate at different concentrations of herbicides Gly and Atra and insecticide Fip. Micronucleus test and other nuclear abnormalities, as well as comet assay and morphometric measurements taken of models' circulating erythrocytes were used as toxicity biomarkers. Pups exposed to Gly (groups Gly-65 ppb and Gly-6500 ppb) were the ones recording the largest amount of nuclear abnormalities; erythrocytes with multilobulated, notched and displaced nucleus were mostly frequent in groups Atra-2 ppb and Gly -65 ppb. All treatments (Gly-6500 ppb, Atra-2 ppb, Atra-200 ppb, Fip-4 ppb and Fip-400 ppb), except for group Gly-65 ppb, led to decreased erythrocyte area, increased "nuclear area: erythrocyte area" ratio, as well as to decreased erythrocyte and erythrocyte nuclei circularity, which highlights the clear effect on the size and shape of these cells. On the other hand, the comet assay did not evidence any genotoxic effect caused by the assessed pesticides. This is a pioneer study on the mutagenic and morphotoxic potential of pesticides in P. expansa eclodides exposed in ovo to Gly, Atra and Fip; therefore, it is an insight on how these compounds can affect the health of these animals.

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This study proposes the description of the development of the postcranial axial skeleton, including vertebrae, gastralium, ribs, sternum, and interclavicle, in Melanosuchus niger. Six nests were marked and two eggs removed from each nest at 24-hr intervals until hatching. For posthatching evaluation, 30 hatchlings were kept in captivity and one exemplar was euthanized at three-day intervals. Samples were diaphanized using potassium hydroxide (KOH), alizarin red S, and Alcian blue. A routinely generally used method was applied for histological evaluation. It was difficult to define in which vertebrae the development of cartilaginous centers began, but it was possible to observe that this condensation advanced in the craniocaudal direction. The condensation started in the vertebral arches and was visibly stronger in the cervical and dorsal regions, advancing to the lumbar, sacral and, last, to the caudal region. The atlas showed a highly different morphology compared with the other cervical vertebrae, with a short intercenter, two neural arches, and a proatlas. The ossification process began in the body of cervical vertebrae III to VIII and alizarin retention decreased in the last vertebrae, indicating a craniocaudal direction in bone development, similar to cartilage formation. In the histological sections of gastralium and interclavicles of M. niger at several development stages, it was possible to observe that these elements showed intramembranous development. Anat Rec, 301:607-623, 2018. © 2017 Wiley Periodicals, Inc.

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The objective of the present study was to analyze chondrogenesis and the ossification pattern of the limbs of Melanosuchus niger in order to contribute with possible discussions on homology and the fusion pattern of autopodial elements and phylogeny. In the Reserva Extrativista do Lago Cuniã, Rondônia, Brazil, six nests were marked and two eggs removed from each nest at 24-hour intervals until hatching. Embryos were cleared using KOH; bone tissue was stained with alizarin red S and cartilage with Alcian blue. Routine staining with HE was also performed. In the pectoral girdle, the scapula showed ossification centers before the coracoid process. In the pelvic girdle, the ilium and the ischium were condensed as a single cartilage, although ossification took place through two separate centers, forming distinct elements in the adult. The pubis developed from an independent cartilaginous center with free end, which reflects its function in breathing. In the initial stages, the stylopodium and the zeugopodium developed from the condensation of a Y-shaped cartilage in the limbs, and differentiation of the primary axis and digital arch were observed. The greatest changes were observed in the mesopodia. In their evolution, Crocodylia underwent a vast reduction in the number of autopodial elements as a consequence of fusions and ossification of some elements. This study shows that the chondrogenesis and ossification sequences are dissociated. Moreover, the differences between M. niger and other species show clear variation in the patterns for these events in Alligatoridae.

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Knowledge on chemical components of the post -hatching eggshell of reptiles may provide indicators of the quality of the diet offered to females kept in captivity. Therefore, the objective of this study was to investigate the chemical characteristics of the calcareous layer, as well as the thickness of Podocnemis expansa post-hatching eggshells. Eggshell thickness was 183±1.405 µm. This value is similar to that of the eggs of other Testudines with flexible eggshells. As for the chemical composition, the following percentages were observed: nitrogen 7.983 ± 0.054; crude protein 49.91 ± 0.324; crude fat 0.068 ± 0.002; mineral matter 20.302 ± 0.807; calcium 13.374 ± 0.647; and phosphorus 0.176 ± 0.003. Knowledge on chemical composition of the eggshell may aid the nutrition of P. expansa raised in commercial facilities, once this species is an alternative and promising source of exotic meat.

O conhecimento sobre os constituintes químicos da casca de ovos pós-eclosão de répteis pode ser um referencial de qualidade da dieta fornecida para as fêmeas que vivem em cativeiro. Assim, este trabalho visa investigar os aspectos químicos que compõem a camada calcária, bem como a espessura da casca do ovo de Podocnemis expansa no período pós-eclosão. A espessura média da casca dos ovos foi de 183 ± 1,405 µm. Esta espessura é condizente com ovos de outros Testudines com casca flexível. Para os constituintes químicos, foram encontrados os seguintes valores médios percentuais: nitrogênio 7,983 ± 0,054, proteína bruta 49,91 ± 0,324, gordura bruta 0,068 ± 0,002, matéria mineral 20,302 ± 0,807, cálcio 13,374 ± 0,647 e fósforo 0,176 ± 0,003. Este conhecimento sobre a composição química da casca poderá auxiliar na criação em escala comercial dessa espécie, uma vez que a P. expansa tem se apresentado como fonte alternativa e promissora de carne exótica.

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The use of pesticides is a widely spread practice in Brazilian agriculture, and dispersion of these substances is an important factor for the fauna and flora. Atrazine is an endocrine disruptor in the xenoestrogen class that is used worldwide in agricultural practices. In Brazil, its use is permitted in several crops. Podocnemis expansa is a representative of the Testudines order that is the largest freshwater reptile of South America. Its distribution enables it to get in contact with molecules that are commonly used as pesticides, which may cause deleterious effects in target populations. In order to evaluate the possible effects of the exposure to atrazine on bone ontogeny of this species, eggs were artificially incubated in sand moistened with water contaminated with atrazine at concentrations equal to 0, 2, 20 or 200 µg/L. Embryos were collected throughout incubation and submitted to diaphanization of soft tissues with potassium hydroxide (KOH); bones were stained with Alizarin red S and cartilages by Alcian blue. Embryos were evaluated for the presence of abnormalities during the different stages of pre-natal development of skeletal elements. No effect of atrazine was observed on bone development during the embryonic phase in P. expansa individuals, in the conditions of this study.

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Knowledge on chemical components of the post-hatching eggshell of reptiles may provide indicators of the quality of the diet offered to females kept in captivity. Therefore, the objective of this study was to investigate the chemical characteristics of the calcareous layer, as well as the thickness of Podocnemis expansa post-hatching eggshells. Eggshell thickness was 183±1.405 μm. This value is similar to that of the eggs of other Testudines with flexible eggshells. As for the chemical composition, the following percentages were observed: nitrogen 7.983 ± 0.054; crude protein 49.91 ± 0.324; crude fat 0.068 ± 0.002; mineral matter 20.302 ± 0.807; calcium 13.374 ± 0.647; and phosphorus 0.176 ± 0.003. Knowledge on chemical composition of the eggshell may aid the nutrition of P. expansa raised in commercial facilities, once this species is an alternative and promising source of exotic meat.(AU)

O conhecimento sobre os constituintes químicos da casca de ovos pós-eclosão de répteis pode ser um referencial de qualidade da dieta fornecida para as fêmeas que vivem em cativeiro. Assim, este trabalho visa investigar os aspectos químicos que compõem a camada calcária, bem como a espessura da casca do ovo de Podocnemis expansa no período pós-eclosão. A espessura média da casca dos ovos foi de 183 ± 1,405 μm. Esta espessura é condizente com ovos de outros Testudines com casca flexível. Para os constituintes químicos, foram encontrados os seguintes valores médios percentuais: nitrogênio 7,983 ± 0,054, proteína bruta 49,91 ± 0,324, gordura bruta 0,068 ± 0,002, matéria mineral 20,302 ± 0,807, cálcio 13,374 ± 0,647 e fósforo 0,176 ± 0,003. Este conhecimento sobre a composição química da casca poderá auxiliar na criação em escala comercial dessa espécie, uma vez que a P. expansa tem se apresentado como fonte alternativa e promissora de carne exótica.(AU)

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Eggshell evaluation may serve as an indicator of the effect of substances released in the environment, which may change eggshell shape, size, structure, and/or chemical composition. Additionally, exposure may interfere with hatching rates in contaminated eggs. The objective of this study was to better understand how exposure to the insecticide methyl parathion interferes with chemical changes in eggshells of Podocnemis expansa throughout their artificial incubation, as well as with egg hatchability. A total of 343 P. expansa eggs were collected in a natural reproduction area for the species. These eggs were transferred to and artificially incubated in the Wild Animal Teaching and Research Laboratory at Universidade Federal de Uberlândia. On the first day of artificial incubation, 0, 35, 350, and 3500 ppb of methyl parathion were incorporated to the substrate. Eggs were collected every three days for chemical analysis of eggshells. Hatchability was evaluated as the number of hatchlings in each treatment, for the eggs that were not used in the chemical analysis. Student's T-test was used for data on eggshell chemical composition, and the Binomial Test for Two Proportions was used in the hatchability analysis, at a 5% significance level. It was observed that the incorporation of methyl parathion to the substrate on the first day of artificial incubation of P. expansa eggs reduced the levels of total fat in the shells throughout their incubation, besides reducing egg hatchability.

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The liver of P. expansa was characterized morphohistologically. To this end, twenty livers from clinicallyhealthy male and female Podocnemis expansa, weighing from 2.0 to 4,5 kg, supplied by the commercial breederFazenda Moenda da Serra, in Araguapaz, state of Goiás, Brazil, were analyzed macro - and microscopically.The coelomatic cavity was opened and the topography of the fresh organs was examined visually. After thehistological preparation, the slides were stained with Hematoxylin and Eosin (HE), Periodic Acid-Schiff(PAS), Gomori Trichrome, Reticulin and Picrosirius. The liver of P. expansa is a voluminous organ with anapproximately rectangular shape and brown coloration, varying from light to dark shades, and is divided into aright lobe, left lobe, and a central portion. The right lobe is the largest of the three portions. The gall bladderis located in a depression in the caudal portion of the right lobe, where the gall duct begins and emptiesinto the duodenum. Histologically, the hepatocytes are arranged in the form of double cords surroundedby winding sinusoidal capillaries. In cross section, they resemble acini containing approximately two to fivehepatocytes surrounding a probable central biliary canaliculus. The hepatocytes are polyhedral or pyramidalin shape, of uniform size, with a few central nuclei and others displaced peripherally, and the cytoplasm islittle eosinophilic when analyzed by the HE staining technique. The parenchyma is supported by delicatereticular fibers surrounding hepatocytes and sinusoids. The parenchyma and perisinusoidal spaces containlarge quantities of melanomacrophages, mainly close to the portal spaces.

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Dentre os répteis, os lagartos e os testudines são o foco de inúmeras investigações que contemplam o estudo de sua ontogenia, contudo, descrições do desenvolvimento e da sequência de ossificação em crocodilianos são escassas. Assim, objetivou-se investigar o padrão de formação e a sequência de ossificação das vértebras e costelas em Caiman yacare (DAUDIN, 1802). Embriões foram coletados em intervalos regulares e submetidos ao protocolo de diafanização e coloração por Aliarina red S. O processo de ossificação da coluna vertebral ocorre no sentido crânio-caudal a partir dos 33 dias. As vértebras se formam a partir de centros de ossificação distintos para os centros, o arco e as apófises. O pró-atlas se forma a partir de dois centros de ossificação distintos que se fundem até o fim do período de incubação. A fusão dorsal dos processos transversos ocorre parcialmente aos 51 dias, dando origem ao diminuto esboço do processo espinhoso. No embrião de 57 dias a articulação entre as costelas, o sacral e o ílio não estava evidente. A morfologia e tamanho das vértebras caudais variam consideravelmente no sentido crânio-caudal. Todas apresentam os processos hemais e iniciam sua ossificação até os 48 dias. C. yacare apresenta um número variado de costelas abdominais, que se ossificam ainda durante o período embrionário. O padrão da esqueletogênese de C. yacare é congruente com de outros répteis, embora existam algumas variações, com particular ênfase na remodelação de estruturas, o que possivelmente reflete as variações do período de incubação entre os diversos répteis relatados.

Among reptiles, lizards and Testudines are the focus of numerous investigations that include the study of its ontogeny, however, descriptions of development and ossification sequence in crocodilians are scarce. Thus, it was aimed to investigate the pattern of training and sequence of ossification of the vertebrae and ribs in Caiman yacare (Daudin, 1802). Embryos were collected at regular intervals and submitted to the protocol of clearing and staining Aliarina red S. The process of ossification of the vertebral column occurs in the craniocaudal direction from the 33 days. The vertebrae are formed from separate ossification centers for the centers, the arch and the transverse processes. The proatlas is formed from two separate ossification centers that fuse to the end of the incubation period. The fusion of dorsal transverse process is partly to 51 days, giving rise to a small sketch of the spinous process. In the embryo of 57 days the link between the ribs, the sacrum and the ilium was not evident. The morphology and size of caudal vertebrae vary considerably in the craniocaudal direction. All have the hemal processes and initiate its ossification up to 48 days. C. yacare has a varied number of abdominal ribs, which ossify even during the embryonic period. The pattern of skeletogenesis C. yacare is consistent with other reptiles, although some variations, with particular emphasis on the remodeling of structures, which possibly reflects the variations in incubation period among the various reptiles reported.

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The aim of the present study was to investigate the sequence of shell bone formation in the embryos of the Pleurodira, Podocnemis unifilis. Their bones and cartilage were collected and cleared before staining. The shell was also examined by obtaining a series of histological slices. All the bony elements of the plastron have independent ossification centers, which subsequently join together and retain two fontanelles until the period of hatching. This turtle has a mesoplastra, which is characteristic of the Podocnemididae. The carapace begins to form concurrently with the ossification of the ribs at the beginning of stage 20. All the plates, except the suprapygal, initiate ossification during the embryonic period. The main purpose of the histological investigation was to highlight the relationship between the formation of the carapace and ribs with that of the neural plates. The costal and neural plates were found not to independent ossification centers, but to be closely related to components of the endoskeleton, originating as expansions of the perichondral collar of the ribs and the neural arches, respectively. Considering the ribs as an endoskeletal element of the carapace, the carapace and plastron begin ossification at the same stage in P. unifilis. This pattern reveals similarities with other Pleurodira, as well as evident variations, such as the presence of the seven neural bones and the presence of only one ossification center in the nuchal plate.

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This paper describes the digestive system of Caiman crocodilus, Melanosuchus niger and Paleosuchus palpebrosus based on anatomical and topographical inferences. The study involves two digestive systems of C. crocodilus, one of M. niger and one of P. palpebrosus, already fixed in 10 percent formaldehyde, belonging to the collection of the Wild Animal Research Laboratory (LAPAS) of the Federal University of Uberlândia. The work begins with a description of the digestive system of the aforementioned crocodilians, followed by topographical associations, aided by photographs taken with a SONY® DSC-H20 camera, X-rays of the gastrointestinal tract and a photograph of the digestive system of C. crocodilus prior to formaldehyding, which also belong to the LAPAS collection. The results indicate that the digestive system of crocodilians consists of a wide mouth, short pharynx, long straight esophagus, dilated stomach in relation to the rest of the tract, pancreas lodged between the first two ventral duodenal loops, coiled small intestine, large intestine with diameter larger than the preceding segments, and cloaca as the terminal portion of the digestive, urinary and reproductive systems. The anatomical and topographical description of the digestive system of C. crocodilus (Linnaeus, 1758) (Crocodylia: Alligatoridae), M. niger (Spix, 1825) (Crocodylia: Alligatoridae) and P. palpebrosus (Cuvier, 1807) (Crocodylia: Alligatoridae) can be extended to the other crocodilians due to interspecies and intraspecific behavioral similarities.

Mediante comparaciones anatómicas y topográficas describimos el sistema digestivo de C. crocodillus, M. nigeri y P. palpebrosus. Se utilizaron dos sistemas digestivos de C. crocodillus, uno de M. nigeri y uno de P. palpebrosus, fijados en formalina al 10 por ciento y pertenecientes al laboratorio de enseñanza e investigación de fauna silvestre (LAPAS) de la Universidade Federal de Uberlândia. En primera instancia se realizó la descripción del sistema digestivo de las mencionadas especies, seguido de comparaciones topográficas. Luego, fueron tomados registros fotográficos con cámara DSC H20 SONY. Adicional a esto, nos apoyamos con radiografías del tracto gastrointestinal y fotografías del sistema digestivo de C. crocodillus antes de ser fijados en formalina. Los resultados demuestraron que el sistema digestivo de estas tres especies de caimanes está constituido por una boca grande, faringe corta, esófago alargado y rectilíneo, estómago dilatado con relación a las otras partes del tracto digestivo, páncreas alojado entre las dos primeras curvaturas duodenales ventrales, intestino delgado plegado, intestino grueso con un diámetro mayor en relación a los segmentos anteriores y una cloaca donde también terminan los sistemas urinarios y reproductor. La descripción anatómica y topográfica del sistema digestivo de C. crocodillus, M. niger y P. palpebrosus puede ser extrapolada para otros cocodrilos por la semejanza comportamental interespecies e intraespecíficas.

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The present study analyzed the radiographic anatomy and determined thegastrointestinal transit time of Podocnemis unifilis. We used ten animals belonging to LAPAS fromthe Federal University of Uberlândia, Uberlândia, Minas Gerais State, Brazil. The animals wereorally fed with a barium sulphate suspension at 10 mL kg-1 mixed with mineral oil, at a ratio of70% of barium sulphate for 30% of mineral oil. Afterwards, the animals underwent radiographyin a dorsum ventriloquoal position, with the X-ray device adjusted at 72 Kv and 200 mA, in timeintervals to follow the permanency of contrast in the organism. Five minutes after the contrastwas supplied, the stomach was filled. After sixteen hours the contrast advanced to the smallintestine. In 48 hours, the whole small intestine and part of the colon were fulfilled. On the 9thday the stomach was empty and the contrast advanced to the colon. On the 11th day, the colonwas totally fulfilled, and the contrast was close to cloaca. On the 18th day all contrast waseliminated by the animal. Total time for contrast elimination was, in average, 17.6 ± 2.4 days,with the minimum of 12 and maximum of 22 days, with temperature at 27ºC. The digestion ofthe food was slower in the duodenum, and faster in the colon-rectum, which presents lowerindices of repletion.(AU)

Avaliou-se aspectosanátomo-radiográficos bem como o tempo de trânsito gastrintestinal em Podocnemis unifilis.Foram utilizados 10 animais pertencentes ao Laboratório de Pesquisas em Animais Silvestres(LAPAS) da Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brasil. Aos animaisfoi administrada, por via oral, uma suspensão de sulfato de bário 10 mL kg-1 misturada com óleomineral na proporção de 70% de sulfato de bário para 30% de óleo. Posteriormente, os animaisforam radiografados dorso-ventralmente, com o aparelho de raios-X regulado para 72 Kv e 200mA, em intervalos de tempo pré-estabelecidos. Em média, cinco minutos após a administraçãodo contraste, a porção proximal do estômago estava preenchida. Após 16 horas, o contrasteprogrediu para o intestino delgado. Com 48 horas, todo o intestino delgado e parte do intestinogrosso estavam preenchidos. No 9 dia o estômago apresentava-se vazio e o contraste progrediupara o cólon. No 11 dia, o contraste encontrava-se na região do reto e o duodeno encontrava-sevazio. No 14 dia, o intestino delgado já estava totalmente sem preenchimento. No 18 dia, todo ocontraste foi eliminado. O tempo total de eliminação do contraste foi, em média, de 17,6 ± 2,4dias, sendo o mínimo de 12 e o máximo de 22 dias em temperatura média de 27°C. A digestão doalimento foi mais lenta no duodeno e mais alta no cólon-reto, que alcançou menores índices derepleção.(AU)

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To gain an understanding of the detailed anatomical aspects of Mazama gouazoubira (brocket deer), this paper describes the relationships between its spinal cord and the vertebral canal, adding information with a clinical and surgical approach. Three specimens of M. gouazoubira were prepared following the methods normally used in anatomy. The epaxial muscles and vertebral arches were removed to expose the spinal cord and the spinal nerve roots. The dimensions of the medullary segments were measured using a pachymeter with 0.05 mm precision. The spinal cord is cylindroidal, dorsoventrally flattened, with an average craniosacral length of 656.27 mm, and has two dilatations corresponding to the cervical and lumbar intumescences. The cervical, thoracic, lumbar and sacrocaudal segments showed an average length of 175.07, 226.03, 123.47 and 43.63 mm, with indices of 28.02, 35.34, 19.68 and 6.93%, respectively. The medullary cone, whose average length is 46.27 mm, begins between L2 and L3 and ends between S1 and S2, with a mean index of 7.53%. The overall average distance between the nerve roots of the cervical, thoracic and lumbosacral segments was 2.23, 2.06 and 1.98 cm, respectively. (AU)

Propondo conhecer os aspectos anatômicos pormenorizados de Mazama gouazoubira (veado catingueiro), o presente trabalho descreve as relações entre sua medula espinal e o canal vertebral, adicionando informações com enfoque clínico-cirúrgico. Utilizaram-se três espécimes de M. gouazoubira que foram preparados seguindo métodos usuais em anatomia. Retirou-se a musculatura epiaxial e os arcos vertebrais para a exposição da medula espinal e raízes dos nervos espinais. As dimensões dos segmentos medulares foram obtidas utilizando um paquímetro de precisão 0,05 mm. A medula espinal possui a forma cilindróide, aplanada dorsoventralmente, com comprimento crânio-sacral médio de 656,27 mm, possui duas dilatações correspondentes às intumescências cervical e lombar. Os segmentos cervical, torácico, lombar e sacro-caudal apresentam 175,07; 226,03; 123,47 e 43,63 mm decomprimento médio, com índices de 28,02; 35,34; 19,68 e 6,93% respectivamente. O cone medular de comprimento médio 46,27 mm inicia-se entre L2 e L3 e termina em S1 e S2, com índice médio de 7,53%. A média geral obtida para a distância entre as raízes dos nervos dos segmentos cervical, torácico e lombossacral foi de 2,23; 2,06 e 1,98 cm, respectivamente. (AU)

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In order to determine the normal stages of formation in the sequence ofossification of the cranium of Podocnemis expansa in its various stages of development,embryos were collected starting on the 18th day of natural incubation and were subjected tobone diaphanization and staining. In the neurocranium, the basisphenoid and basioccipitalbones present ossification centers in stage 19, the supraoccipital and opisthotic in stage 20,the exoccipital in stage 21, and lastly the prooptic in stage 24. Dermatocranium: thesquamosal, pterygoid and maxilla are the first elements to begin the ossification process,which occurs in stage 16. However, ossification centers begin to appear in stage 17 in mostof these bone elements, i.e., the frontal, jugal, postorbital, parietal, premaxilla andprefrontal, followed by the palatine and quadratojugal in stage 19 and lastly by the vomer instage 25. The quadrate bone of the splanchnocranium ossifies in stage 23. The mandibleand hyoid apparatus, the dentary, coronoid and supra-angular, show ossification centers instage 16 and the branchial horn I in stage 17. The sequence and synchronization ofossification in P. expansa show similarities as well as differences when compared with otherspecies of Testudines.(AU)

Com o propósito deestabelecer etapas normais de formação da sequência de ossificação do crânio em Podocnemisexpansa, nos diferentes estágios de desenvolvimento, coletaram-se embriões a partir do 18ºdia de incubação natural, os quais foram submetidos à técnica de diafanização e coloraçãodos ossos. No neurocrânio, no estágio 19, o basisfenoide e o basioccipital apresentam centrode ossificação; no estágio 20, o supraoccipital e o opistótico; no estágio 21, o exoccipital;somente no estágio 24, o proótico. Dermatocrânio: o esquamosal, o pterigoide e a maxilasão os primeiros elementos a iniciar o processo de ossificação, que ocorre no estágio 16. Masa maioria desses elementos ósseos apresenta centros de ossificação no estágio 17, são eles:frontal, jugal, pós-orbital, parietal, pré-maxila, pré-frontal, seguido do palatino equadradojugal no estágio 19 e, por último, o vômer no estágio 25. O osso quadrado doesplancnocrânio, no estágio 23. Ossificação da mandíbula e aparelho hioide: tanto odentário, coronoide e o supra-angular apresentam centros de ossificação no estágio 16; ocorpo branquial I, no estágio 17. A sequência e a sincronização da ossificação em P. expansaexibem similaridades, bem como diferenças, quando comparada com outras espécies deTestudines.(AU)

Assuntos

RESUMO

In order to determine the normal stages of formation in the sequence ofossification of the cranium of Podocnemis expansa in its various stages of development,embryos were collected starting on the 18th day of natural incubation and were subjected tobone diaphanization and staining. In the neurocranium, the basisphenoid and basioccipitalbones present ossification centers in stage 19, the supraoccipital and opisthotic in stage 20,the exoccipital in stage 21, and lastly the prooptic in stage 24. Dermatocranium: thesquamosal, pterygoid and maxilla are the first elements to begin the ossification process,which occurs in stage 16. However, ossification centers begin to appear in stage 17 in mostof these bone elements, i.e., the frontal, jugal, postorbital, parietal, premaxilla andprefrontal, followed by the palatine and quadratojugal in stage 19 and lastly by the vomer instage 25. The quadrate bone of the splanchnocranium ossifies in stage 23. The mandibleand hyoid apparatus, the dentary, coronoid and supra-angular, show ossification centers instage 16 and the branchial horn I in stage 17. The sequence and synchronization ofossification in P. expansa show similarities as well as differences when compared with otherspecies of Testudines.

Com o propósito deestabelecer etapas normais de formação da sequência de ossificação do crânio em Podocnemisexpansa, nos diferentes estágios de desenvolvimento, coletaram-se embriões a partir do 18ºdia de incubação natural, os quais foram submetidos à técnica de diafanização e coloraçãodos ossos. No neurocrânio, no estágio 19, o basisfenoide e o basioccipital apresentam centrode ossificação; no estágio 20, o supraoccipital e o opistótico; no estágio 21, o exoccipital;somente no estágio 24, o proótico. Dermatocrânio: o esquamosal, o pterigoide e a maxilasão os primeiros elementos a iniciar o processo de ossificação, que ocorre no estágio 16. Masa maioria desses elementos ósseos apresenta centros de ossificação no estágio 17, são eles:frontal, jugal, pós-orbital, parietal, pré-maxila, pré-frontal, seguido do palatino equadradojugal no estágio 19 e, por último, o vômer no estágio 25. O osso quadrado doesplancnocrânio, no estágio 23. Ossificação da mandíbula e aparelho hioide: tanto odentário, coronoide e o supra-angular apresentam centros de ossificação no estágio 16; ocorpo branquial I, no estágio 17. A sequência e a sincronização da ossificação em P. expansaexibem similaridades, bem como diferenças, quando comparada com outras espécies deTestudines.

Assuntos

RESUMO

To gain an understanding of the detailed anatomical aspects of Mazama gouazoubira (brocket deer), this paper describes the relationships between its spinal cord and the vertebral canal, adding information with a clinical and surgical approach. Three specimens of M. gouazoubira were prepared following the methods normally used in anatomy. The epaxial muscles and vertebral arches were removed to expose the spinal cord and the spinal nerve roots. The dimensions of the medullary segments were measured using a pachymeter with 0.05 mm precision. The spinal cord is cylindroidal, dorsoventrally flattened, with an average craniosacral length of 656.27 mm, and has two dilatations corresponding to the cervical and lumbar intumescences. The cervical, thoracic, lumbar and sacrocaudal segments showed an average length of 175.07, 226.03, 123.47 and 43.63 mm, with indices of 28.02, 35.34, 19.68 and 6.93%, respectively. The medullary cone, whose average length is 46.27 mm, begins between L2 and L3 and ends between S1 and S2, with a mean index of 7.53%. The overall average distance between the nerve roots of the cervical, thoracic and lumbosacral segments was 2.23, 2.06 and 1.98 cm, respectively.

Propondo conhecer os aspectos anatômicos pormenorizados de Mazama gouazoubira (veado catingueiro), o presente trabalho descreve as relações entre sua medula espinal e o canal vertebral, adicionando informações com enfoque clínico-cirúrgico. Utilizaram-se três espécimes de M. gouazoubira que foram preparados seguindo métodos usuais em anatomia. Retirou-se a musculatura epiaxial e os arcos vertebrais para a exposição da medula espinal e raízes dos nervos espinais. As dimensões dos segmentos medulares foram obtidas utilizando um paquímetro de precisão 0,05 mm. A medula espinal possui a forma cilindróide, aplanada dorsoventralmente, com comprimento crânio-sacral médio de 656,27 mm, possui duas dilatações correspondentes às intumescências cervical e lombar. Os segmentos cervical, torácico, lombar e sacro-caudal apresentam 175,07; 226,03; 123,47 e 43,63 mm decomprimento médio, com índices de 28,02; 35,34; 19,68 e 6,93% respectivamente. O cone medular de comprimento médio 46,27 mm inicia-se entre L2 e L3 e termina em S1 e S2, com índice médio de 7,53%. A média geral obtida para a distância entre as raízes dos nervos dos segmentos cervical, torácico e lombossacral foi de 2,23; 2,06 e 1,98 cm, respectivamente.

Assuntos