Embryonic development of the scorpion mud turtle (Kinosternon scorpioides) bred in captivity.

Background: The developmental biology of Kinosternon scorpioides is described, based on the phenotype. This species is important for the flora because they are excellent seed disseminators. In addition, basic embryological information is not yet fully clarified, and this research provides unprecedented information on the chelonian embryology of the Amazonian fauna. Aim: The present study aims to identify the embryology of K. scorpioides in captivity during different periods. Methods: Females were monitored throughout the reproductive cycle, by video monitoring, to identify nests and the presence of newly laid eggs. At regular weekly intervals, embryo samples were collected fixed in a 4% paraformol solution and preserved in 70% alcohol. For the embryonic characterization, we used a stereomicroscope and the scanning electron microscopy method. Results: We describe 15 embryonic stages for a 15-week (105-day) incubation process. Only at 42 days (6th week) was the morphological characterization of a chelonian observed and at the 12th week (Stage XII), the phenotypic characterization of the species K. scorpioides. Conclusion: In view of the evidence, we found that these phases are similar to the other turtles, with structural variations in the appearance and disappearance of structures due to the specific characteristics of the species.

Morphological study of larynx, trachea, and lungs of Didelphis marsupialis (LINNAEUS, 1758).

BACKGROUND AND AIM: From a biomedical point of view, the value of marsupials as a model of primitive mammals is indisputable. Among its species, the possum is a model that allows the study of the ontogeny of different organic systems, as well as their physiological aspects. The relevance of anatomical, functional, evolutionary, and phylogenetic study of marsupials for the development of comparative morphology is extensively documented in the literature. However, there are still many aspects to be further evaluated, as the anatomy and histology of the respiratory tract of this species. The aim of this study was to describe the morphology of the larynx, trachea, and lungs of Didelphis marsupialis. MATERIALS AND METHODS: Five adult male animals were donated to the Comparative Animal Anatomy Laboratory - LAAC/CCAA-UFMA, for morphological studies. Specimens were washed in running water to perform biometrics. Then, they were fixed with 10% formaldehyde solution. After the fixation period, the specimens were positioned in dorsal decubitus position, for dissection of the respiratory system organs, by opening the ventral region of the neck and thoracic cavity, with subsequent removal of the pectoral muscles, ribs, and sternum. For histological analysis, fragments of 1 cm2 of the larynx (epiglottis and thyroid cartilages), trachea, and lungs were collected and fixed in 10% formaldehyde solution. Right after fixation, the fragments were dehydrated in increasing concentrations of ethyl alcohol (70, 80, 95, and 100%), diaphanized in xylene, embedded in paraffin, and sectioned into thin slices of 5 µm using a microtome. Sections were stained using the hematoxylin and eosin technique. RESULTS: Anatomically, the larynx starts right after the pharynx. It consisted of four cartilages: Epiglottis, cricoid, thyroid, and arytenoid. The trachea was made of dorsally incomplete cartilaginous rings. At the entrance of the thoracic cavity, it bifurcated into the left and right main bronchus. The left lung was smaller than the right lung, with two lobes (cranial and caudal). The right lung presents the cranial, middle, caudal, and accessory lobes. Histologically, the epiglottis consisted of elastic cartilage and is covered by a non-keratinized stratified squamous epithelium. Thyroid cartilage is made of hyaline cartilage covered by smooth muscle. The trachea presents hyaline cartilage, with ciliated pseudo-stratified epithelium, serous glands, isogenic groups of chondrocytes, and perichondrium. The lung consisted of bronchi, bronchioles, and alveoli, also presenting blood vessels and arteries. CONCLUSION: Morphologically, the larynx, trachea, and lungs of D. marsupialis were similar to those of the other Didelphids described in the literature.

Genotoxic and hematological parameters in Colossoma macropomum (Pisces, Serrasalmidae) as biomarkers for environmental impact assessment in a protected area in northeastern Brazil.

Genotoxic and hematological parameters in tambaqui (Colossoma macropomum), a native freshwater fish, were used as biomarkers to assess exposure to environmental stressors within the Maracanã Protected Area of Maranhão State, Brazil. Fish were sampled at two sites-Serena Lagoon (control) and Ambude River-on four occasions (dry and rainy season), and biometric data (length and weight) recorded and blood collected from all fish for analysis. Erythrocyte indices-mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration-were calculated. Blood samples were stained with Giemsa and acridine orange, and microscopically examined for micronuclei and morphological nuclear abnormalities. Micronuclei were observed in fish from both sites, although the frequency was significantly higher in fish from the Ambude River and morphological nuclear abnormalities were only observed in fish from the Ambude River. More morphological nuclear abnormalities and a larger number of micronuclei were observed in erythrocytes stained with acridine orange compared with those stained with Giemsa. On average, erythrocyte indices were lower in fish from the Ambude River than from the Serena Lagoon. The results confirm that genotoxic and hematological parameters in C. macropomum can be used as indicators of environmental health and could be valuable tools for monitoring environmental conditions within protected areas.

Body and testicular biometric parameters of the scorpion mud turtle (Kinosternon scorpioides) / Parâmetros biométricos corporais e testiculares de tartaruga (Kinosternon scorpioides)

The reptile Kinosternon scorpioides is a freshwater chelonian, popularly known as jurará, and is found in the Baixada Maranhense, Maranhão State, Brazil. Due to the lack of scientific information on the reproductive biology of the species, current paper describes the body and testicular biometry and the gonad -somatic index (GSI) in adult specimens collected from the natural environment. Twenty male adults were collected in the rainy (n = 10) and dry (n = 10) seasons. Data were derived from the body, testis size and GSI and tests of correlation between these measures were performed. The body biometrics of free-living Kinosternon scorpioides is similar to those found in other studies for adult animals bred in captivity. The body weight was higher in animals collected in the rainy season than that in animals collected in the dry season. The testis size presents variations among animals captured during the rainy and dry season, but the gonadossomatic index did not vary between different groups of animals. Further studies were suggested related to the levels of sexual steroid hormones and behavioral studies to understand the factors related to the species´s reproductive cycle.

O réptil Kinosternon scorpioides é um quelônio de água doce popularmente conhecido como jurará, encontrado na Baixada Maranhense, Maranhão, Brasil. Diante da carência de informações científicas sobre a biologia reprodutiva desta espécie, objetivamos descrever a biometria testicular e corporal, assim como, e o índice gonadossomático (IGS), em espécimes adultos provenientes de habitat natural. Utilizamos 20 indivíduos machos adultos, coletados no período chuvoso (n = 10) e período seco (n = 10), dos quais extraímos informações da biometria corpórea e testicular, assim como o índice gonadossomático e testes de correlação entre estas medidas. Encontramos que a biometria corpórea de Kinosternon scorpioides de vida livre é semelhante ao encontrado em outros estudos com animais adultos criados em cativeiro. No entanto, o peso corpóreo foi maior em animais coletados no período chuvoso que o encontrado em animais coletados no período seco. A biometria testicular apresenta variações entre os animais de período chuvoso e seco, no entanto os índices gonadossomáticos não variaram entre os animais dos diferentes grupos, portanto sugerimos estudos relacionados a níveis de hormônios esteroides sexuais e estudos comportamentais para auxiliar na compreensão dos fatores relacionados ao ciclo reprodutivo da espécie.

Seasonal morphological variation of the vas deferens of scorpion mud turtle (Kinosternon scorpioides) / Variação morfológica sazonal dos ductos deferentes de tartaruga jurará (Kinosternon scorpioides)

This study aimed to characterize the morphology of the vas deferens of Kinosteron scorpioides by macroscopic and microscopic analysis. Were used 20 adult male jurarás collected at regular intervals during the year and divided into four experimental groups in the rainy and dry seasons, being processed for light microscopy, scanning electron microscopy and transmission electron microscopy. Morphometry for tubular and luminal diameters and epithelial height were also performed. On rainy season, vas deferens presented pseudostratified epithelium with cylindrical cells, spermatozoids and milky fluid in the lumen, with cytoplasmic organelles and lipid vesicles. On dry season, epithelium was pseudostratified with cuboid cells, with cellular debris and no spermatozoids. There was significant variation (p<0,05) for morphometry of vas deferens, with lower values of tubular and luminal diameters on rainy season, and higher epithelial height on dry season.

Este estudo teve como objetivo caracterizar a morfologia dos ductos deferentes de Kinosteron scorpioides por meio de análise macroscópica e microscópica. Foram utilizados 20 machos adultos, coletados em intervalos regulares durante o ano, os quais foram divididos em quatro grupos experimentais nas estações chuvosa e seca. Os ductos deferentes foram processados para análise por microscopia de luz, microscopia eletrônica de varredura e microscopia eletrônica de transmissão. Morfometria para diâmetros tubular e luminal e altura epitelial também foram realizadas. Na época das chuvas, o ducto deferente apresentou epitélio pseudoestratificado com células cilíndricas, espermatozoides e líquido leitoso no lúmen, além de com organelas citoplasmáticas e vesículas lipídicas. Na estação seca, o epitélio do ducto deferente foi do tipo pseudoestratificado com células cuboides e debris celulares, sendo que nenhum espermatozoide foi encontrado nesta estação. Houve variação significativa (p <0,05) para a morfometria dos ductos deferentes, com menores valores de diâmetros tubular e luminal na estação chuvosa, e maior altura do epitélio na estação seca.

Spermatogenic cycle length and sperm production in the freshwater turtle Kinosternon scorpioides.

Kinosternon scorpioides is a Brazilian freshwater turtle that belongs to the class Reptilia, encompassing almost 10,000 species. Nevertheless, very little is known about the testicular quantitative parameters, particularly those related to spermatogenesis, in this vertebrate class. Our main objectives were to investigate in detail the structure and function of the testis in K. scorpioides, particularly the aspects related to spermatogenic cycle length and Sertoli cell (SC) and spermatogenic efficiencies. Nine sexually mature turtles were examined, and intraperitoneal bromodeoxyuridine injections were administered to estimate duration of spermatogenesis. Based on the acrosome development in spermatids and the overall germ cell associations, 10 stages of the seminiferous epithelium cycle were characterized. Similar to birds, humans, and some primate species, several stages were observed per seminiferous tubule cross-sections. One spermatogenic cycle and the entire spermatogenic process lasted, respectively, 12 and 53 days. The SC efficiency (number of round spermatids per SC) and daily sperm production per gram of testis were, respectively, 20 and 40 million spermatids. As established for mammals, our findings suggest that SC efficiency is also a critical determinant of sperm production in reptiles. To our knowledge, this is the first study to investigate the kinetics of spermatogenesis and testis function in any reptilian species. Besides allowing a better understanding of reproductive biology in reptiles, these data will be useful in comparative studies. Moreover, these results could provide the basis for investigations related to the evaluation of spermatogonial stem cell physiology niche in Kinosternon scorpioides.

Biochemical values of red-tailed boa (Boa constrictor) / Valores bioquímicos de jiboia (Boa constrictor)

It was determined the average values of the following blood biochemical indicators of boas (Boa constrictor): glucose, urea, creatinine, aspartate aminotransferase (AST), alanine transaminase (ALT), amylase and lipase, and compared the results obtained concerning sex. A total of 12 Boa constrictor specimens were used, seven males and five females. The average of the biochemical indicators between males and females had no significant difference. The traditional biochemical techniques have been useful to determine these indicators to this species...

Foram determinados os valores médios dos indicadores bioquímicos sanguíneos: glicose, ureia, creatinina, aspartato aminotransferase (AST), alanina aminotransferase (ALT), amilase e lipase de jiboias (Boa constrictor) e comparados os valores das concentrações encontradas entre os grupos de machos e fêmeas. Foram utilizados 12 espécimes de Boa constrictor, dos quais sete machos e cinco fêmeas. A comparação das médias dos indicadores bioquímicos entre os grupos de machos e fêmeas indicou ausência de influência significativa de fatores sexuais. As técnicas bioquímicas tradicionais foram adequadas para a determinação desses indicadores para esta espécie...

Morfologia dos órgãos genitais masculinos do jurará kinosternon scorpioides (chelonia: kinosternidae) / Morphology of the male genital organs of the scorpion mud turtle kinosternon scorpioides (chelonia: kinosternidae)

Kinosternon scorpioides é uma pequena tartaruga semi-aquática, típica de água doce, de distribuição geográfica bastante diversificada, encontrada no estado do Maranhão, onde é denominada de jurará ou muçuã. Sua carne é uma excelente fonte de proteína e a despeito da legislação vigente, é comercializado nas praias e feiras da cidade de São Luís e consumido nos restaurantes sob a forma de farofa servida em casquinha. Os órgãos genitais do macho foram estudados visando fornecer dados morfológicos da própria espécie, que poderão ser utilizados na biologia reprodutiva voltada para ações de preservação em cativeiro. Compõe-se a amostra de 10 machos adultos, obtidos mediante apreensões do IBAMA-MA (Proc. nº 020.12.002400/99-31, licença nº 002/01), os quais foram eutanaziados conforme normas do Comitê de Ética do Curso de Medicina Veterinária, Universidade Estadual do Maranhão. A cavidade celomática foi aberta e os órgãos fixados em solução aquosa de formaldeído 10 por cento, e posteriormente dissecados. Os testículos possuem formato ovóide e coloração amarelo-ouro. Os epidídimos convolutos estavam aderidos dorsalmente à superfície medial dos testículos, terminando em um pequeno ducto deferente. Os ductos deferentes não forma-ram nenhuma ampola distinta, abrindo-se na cloaca. O pênis sulcado, localizado no assoalho da cloaca, estendeu-se até a cauda, composto de raíz, corpo e glande. A morfologia dos órgãos reprodutivos destes animais assemelha-se aos de outras tartarugas, sugerindo uma morfologia conservada entre as tartarugas.

Kinosternon scorpioides is a small semi-aquatic turtle, typical of fresh-water, with wide geographic distribution. It is found in the state of Maranhão, where is called jurará or muçuã. Its meat is an excellent protein source and despite current legislation, it is commercialized at beaches and markets in the city of São Luis, consumed in restaurants as an appetizer in its own shell. The constitutive elements of the male genital organs were studied, aiming to provide morphological data of the species which could be used in reproductive biology aimed at actions towards its preservation in captivity. The sample was composed of 10 adult males, captured by IBAMA-MA (Proc. nº 020.12.002400/99-31, license nº 002/01), euthanized, following rules from the Ethics Committee of UEMA's Veterinary Medicine School. The choelomic cavity was opened and the organs were fixed in formaldehyde 10 percent and subsequently dissected. The testis of K. scorpioides had ovoid shape and golden yellow coloration. The cylindrical epididymidis adhered dorsal-wise to the medial surface of the testis, ending in a small deferent duct. The deferent ducts did not form distinct blister and opened inside cloaca. The furrowed penis, located in the base of the cloaca, extending itself until the tail and it was composed by root, body and free part. The morphology data of the reproductive organs of these animals was similar to other turtles such as the sea turtle, suggesting a conservative morphological presentation among turtles.