Non-venomous snakebites in the Western Brazilian Amazon

Abstract INTRODUCTION: In this study, we examined the clinical manifestations, laboratory evidence, and the circumstances of snakebites caused by non-venomous snakes, which were treated at the Regional Hospital of Juruá in Cruzeiro do Sul. METHODS: Data were collected through patient interviews, identification of the species that were taken to the hospital, and the clinical manifestations. RESULTS: Eight confirmed and four probable cases of non-venomous snakebites were recorded. CONCLUSIONS: The symptoms produced by the snakes Helicops angulatus and Philodryas viridissima, combined with their coloration can be confused with venomous snakes (Bothrops atrox and Bothrops bilineatus), thus resulting in incorrect bothropic snakebite diagnosis.

TGF-ß1 polymorphism in American tegumentary leishmaniasis in a Southern Brazilian population

Abstract INTRODUCTION: Genetic polymorphisms define the cytokine production leading to susceptibility or resistance to diseases. We studied the cytokine polymorphism in the development of tegumentary leishmaniasis (TL). METHODS: Genotyping of TNF-α, TGF-β1, IFN-γ, IL-6, and IL-10 were performed by polymerase chain reaction assay. RESULTS: G and C alleles of TGF- β1 (codon 25) were the most common in controls and patients, respectively. G/G was the most frequent genotype in controls, and G/C and C/C in patients. CONCLUSIONS: G/G genotype of codon 25 in TGF-β1 appeared to confer resistance, and G/C and C/C genotypes, susceptibility to TL in this population.

Clinical and laboratory features distinguishing between Deinagkistrodon acutus and Daboia siamensis envenomation

There are 6 species of venomous snakes in Taiwan. Two of them, Deinagkistrodon acutus (D. acutus) and Daboia siamensis (D. siamensis), can cause significant coagulopathy. However, a significant proportion of patients with snakebites cannot identify the correct snake species after envenomation, which hampers the application of antivenom. Hence, the differential diagnosis between the two snakebites by clinical presentations is important. This study aims to compare their clinical and laboratory features for the purpose of differential diagnosis between the two snakebites. Methods: We retrospectively reviewed the medical records of patients who arrived at the emergency department due to D. acutus or D. siamensis envenomation, between 2003 and 2016, in one medical center in eastern Taiwan. Since these snakebites are rare, we also included 3 cases reported from another hospital in central Taiwan. Results: In total, 15 patients bitten by D. acutus and 12 patients by D. siamensis were analyzed. Hemorrhagic bulla formation and the need for surgical intervention only presented for D. acutus envenomation cases (Both 53.3% vs. 0.0%, P= 0.003). As to laboratory features, lower platelet counts (20.0 × 103/µL [interquartile range, 14-66 × 103/µL] vs. 149.0 × 103/µL [102.3-274.3 × 103/µL], P = 0.001), lower D-dimer level (1423.4 µg/L [713.4-4212.3 µg/L] vs. 12,500.0 µg/L [2351.4-200,000 µg/L], P = 0.008), higher proportion of patients with moderate-to-severe thrombocytopenia (platelet count < 100 × 103/µL) (80% vs. 16.7%, odds ratio (OR) = 20.0, 95% CI, 2.77-144.31; P = 0.002), and lower proportion of patients with extremely high D-dimer (> 5000 ng/mL) (16.7% vs. 66.7%, adjusted OR = 0.1 (95% CI, 0.01-0.69; P = 0.036) were found among cases of D. acutus envenomation compared to D. siamensis envenomation. The combination of hemorrhagic bulla, thrombocytopenia, and a lack of extremely high D-dimer had good discriminatory power (area under the curve (AUC) = 0.965; 95% CI, 0.904-1.00) for distinguishing D. acutus from D. siamensis envenomation. Conclusions: The presentation of moderate to severe thrombocytopenia (platelet count < 100 × 103/µL) and hemorrhagic bulla formation may indicate D. acutus envenomation. However, the envenomed patient with extremely high D-dimer levels may indicate a D. siamensis envenomation. These findings may help diagnose and select the right antivenom in patients with unknown snakebites who present significant coagulopathy.(AU)

Evaluation of sperm quality of Erythrolamprus poecilogyrus sublineatus (Cope, 1860) (Serpentes, Dipsadidae) / Avaliação da qualidade seminal de serpentes Erythrolamprus poecilogyrus sublineatus (Cope, 1860) (Serpentes, Dipsadidae)

Abstract Erythrolamprus poecilogyrus sublineatus (Cope, 1860), is a species widely distributed in the Pampa Domain, occurring in Rio Grande do Sul, Argentina and Uruguay, mainlyin the pampa region. In the coastal region of southern Brazil this is serpent is considered one of the most abundant. The purpose of the present study is to describe the techniques of sperm evaluation in vitro for E. poecilogyrus sublineatus in the coastal plain of Rio Grande do Sul, Brazil. After laparatomy the efferent vases were collected and the semen was diluted in 1ml Beltsville Thawing Solution. The characteristics of motility, membrane integrity, mitochondria, acrosome, DNA, cell viability and cellular functionality were evaluated. Fluorescent probes were used for the evaluation of sperm structure in epifluorescence microscope. With the techniques described, it was possible to identify intact and injured cells, enabling the determination of cell characteristics for the spring season (October and November). It was observed in the analyses that 80% of sperm cells were mobile and that 84.1 ± 8.0% of sperm membranes were intact. The standards found were of 48 ± 13.8% of intact acrosome, 73.6 ± 6.0 of perfect DNA and of 91.8 ± 4.0 of functional mitochondria. Thus, these values from the sperm analysis can be used as standards for the species Erythrolamprus poecilogyrus sublineatus.

Resumo Erythrolamprus poecilogyrus sublineatus (Cope, 1860), é uma espécie amplamente distribuída no Domínio Pampa, ocorrendo no Rio Grande do Sul, Argentina e Uruguai, principalmente na região dos pampas. Na região costeira do extremo sul do Brasil essa é uma das serpentes consideradas mais abundantes. O objetivo deste estudo é descrever as técnicas de avaliação espermática in vitro para E. poecilogyrus sublineatus da planície costeira do Rio Grande do Sul, Brasil. Após laparatomia os vasos eferentes foram coletados e o sêmen diluído em 1ml Beltsville Thawing Solution. Foram avaliadas as características de motilidade, integridade de membrana, mitocôndria, acrossoma, DNA, viabilidade celular e funcionalidade celular. Foram utilizadas sondas fluorescentes para avaliação das estruturas espermática em microscópio de epifluoescência. Com as técnicas descritas foram possível identificar células integras e lesadas, podendo determinar as características celulares para o período de primavera (outubro e novembro). Nas análises foi observado que 80% das células espermáticas estavam móveis e que 84,1 ± 8,0% das membranas espermáticas estavam íntegras. Os padrões encontrados para foram de 48 ± 13,8% de acrossoma íntegro, 73,6 ± 6,0 de DNA íntegro e de 91,8 ± 4,0 de mitocôndria funcional. Desta forma, esses valores das análises espermáticas podem ser utilizados como padrão para a espécie Erythrolamprus poecilogyrus sublineatus.

Reproductive biology of the Green Ground Snake Erythrolamprus poecilogyrus sublineatus (Serpentes: Dipsadidae) in Subtropical Brazil

ABSTRACT We investigated reproductive features of the dipsadid snake Erythrolamprus poecilogyrus sublineatus in the southernmost Brazilian coast, a subtropical region characterized by well-marked seasons. Females are significantly smaller than males, have a shorter tail, and reach sexual maturity at later times along their development. In contrast to tropical subspecies, E. p. sublineatus females presented a seasonal pattern, with secondary follicles occurring from late winter to early autumn and egg production restricted to the whole spring and early summer. Males presented seasonal variation in testes volume (increase in autumn and decrease in winter) while no significant seasonal variation was found in ductus deferens width. The number of oviductal eggs varied from two to nine, thus, real fecundity is also inferior than that observed in tropical E. poecilogyrus forms. Considering the thermal requirements for reproduction, it is possible that the colder climatic conditions of the southern Brazilian coast have shaped the seasonal reproductive pattern in E. p. sublineatus. The shorter body size of this subspecies may also represent a conditioning factor of low fecundity.

Evaluación de análisis de endemicidad y PAE para identificar trazos generalizados, a partir de las serpientes del estado de Hidalgo, México / Evaluation of PAE and endemicity analysis for identifying generalized tracks using snakes in Hidalgo, Mexico

Resumen:Uno de los conceptos centrales en la Panbiogeografía es el trazo generalizado, el cual representa una biota ancestral que se ha fragmentado por eventos geológicos y puede recuperarse a través de distintos métodos, que incluyen el análisis de simplicidad de endemismos (PAE) y el análisis de endemicidad (AE). El PAE es un método frecuentemente utilizado para la identificación de trazos generalizados, mientras que el AE fue diseñado para encontrar áreas de endemismo, pero recientemente se ha usado también para identificar trazos generalizados. En este trabajo se evaluaron ambos métodos para la identificación de los trazos generalizados a partir de los datos de 84 serpientes distribuidas en el estado de Hidalgo, México. Con el PAE se obtuvo un trazo generalizado formado por tres trazos individuales (Agkistrodon taylori, Crotalus totonacus y Pliocercus elapoides), que corresponden a sinapomorfías que apoyan al clado principal. La prueba de robustez estadística mostró un soporte del 89 %, mientras que con el AE se identificaron dos áreas de endemismo con valores del índice de endemicidad de 2.71-2.96 y 2.84- 3.09 respectivamente, las cuales fueron transformadas a trazos generalizados; el primero formado por tres trazos individuales (Micrurus bernadi, Rhadinaea marcellae y R. quinquelineata) y el segundo formado por dos trazos individuales (Geophis mutitorques y Thamnophis sumichrasti). Estos trazos generalizados pueden considerarse un solo patrón de distribución, dada la cercanía geográfica y su topología. Al compararse los métodos se observó que ambos son útiles para la identificación de trazos generalizados, y aunque son independientes, se sugiere su uso de manera complementaria. Sin embargo, para una correcta aplicación e interpretación de los resultados, es necesario considerar las bases teóricas de cada método, así como la correcta elección del tamaño de las unidades de estudio. En el caso particular del AE si se utilizan tamaños de celda pequeños éstos pueden resultar ideales para la búsqueda de patrones biogeográficos a través de límites geopolíticos y esta información puede favorecer la realización de pro- puestas de conservación a nivel estatal que consideren a las especies con distribuciones restringidas, pues la pérdida de éstas representaría la extinción de linajes únicos.

Abstract:One of the most important concepts in Panbiogeography is the generalized track, which represents an ancestral biota fragmented by geological events that can be recovered through several methods, including Parsimony analysis of endemicity (PAE) and endemicity analysis (EA). PAE has been frequently used to identify generalized tracks, while EA is primarily designed to find areas of endemicity, but has been recently proposed for identifying generalized tracks as well. In this study we evaluated these methods to find generalized tracks using the distribution of the 84 snake species of Hidalgo. PAE found one generalized track from three individual tracks (Agkistrodon taylori, Crotalus totonacus and Pliocercus elapoides), supported by 89 % of Bootstrap, and EA identified two generalized tracks, with endemicity index values of 2.71-2.96 and 2.84-3.09, respectively. Those areas were transformed to generalized tracks. The first generalized track was retrieved from three individual tracks (Micrurus bernadi, Rhadinaea marcellae and R. quinquelineata), and the second was recovered from two individual tracks (Geophis mutitorques and Thamnophis sumichrasti). These generalized tracks can be considered a unique distribution pattern, because they resembled each other and agreed in shape. When comparing both methods, we noted that both are useful for identifying generalized tracks, and although they can be used independently, we suggest their complementary use. Nevertheless, to obtain accurate results, it is useful to consider theoretical bases of both methods, along with an appropriate choice of the size of the area. Results using small-grid size in EA are ideal for searching biogeographical patterns within geopolitical limits. Furthermore, they can be used for conservation proposals at state level where endemic species become irreplaceable, and where losing them would imply the extinction of unique lineages. Rev. Biol. Trop. 64 (4): 1611-1624. Epub 2016 December 01.

On a Haemogregarine sp. [protozoa, apicomplexa, adeleina] naturally infecting the viper Bitis arientans in Saudi Arabia with reference to the host-parasite relationship

The study described the developmental stages of a haemogregarine species in the blood and tissues of the viper Bitis arientans. Two out of 9 [22.2%] snakes from the south western region of Saudi Arabia, and recorded for the first time in such locality. The erythrocytic parasites were differentiated into three forms: the youngest form [trophozoite] measuring 7.34 +/- 0.16 x 3.38 +/- 0.07 micro m; the intermediate form [developing gametocyte] measuring 13.36 +/- 0.20 x 5.11 +/- 0.11 micro m and the largest form [mature gametocyte] measuring 18.69 +/- 0.32 x 4.32 +/- 0.16 micro m. None of the leucocytes seemed to be parasitized. Also, two types of meronts were detected in lung endothelial cells of infected vipers. Small meronts [micromeronts] measured 21.86 +/- 0.28 x 16.13 +/- 0.25 micro m and yielded about 12 merozoites. The large meronts [macromeronts] measured 38.09 +/- 0.33 x 21.52 +/- 0.32 micro m and yielded 28-42 merozoites. Random distribution of nuclei was observed in early meronts of both sizes, meanwhile peripheral arrangement of nuclei characterizing the subsequent developing events of meronts [ectomerogony]. Histopatho-logical studies showed that the infected erythrocytes were hypertrophied, mechanically stretched and their cytoplasm was faintly stained due to dehaemoglobinization. The host cell nucleus was elongated and laterally displaced. Trabeculae of the infected lung exhibited marked thickening and alveoli were collapsed in various degrees. Haemorrhagic foci and spongy structures were detected in some infected lung tissues. Formation of fibrous tissues around the meronts was seen in some foci

The Snakes of Osun Grove: a World Heritage Site in Osogbo, Nigeria

The Osun Grove, Osogbo, Nigeria, is a protected area covered by riparian forest, dry high forest and derived savanna. In January and June 2000 a total of 25 of snake species were recorded with Afronatrix anoscopus and Calabaria reinhardti being prominent. The incidence of Philothamnus semivariegatus, a savanna species, may be the result of the invasive savanna produced by farming activities around the grove. Nine species, led by A. anoscopus, accounted for 69.7 % of the snake community. The dominant species are either aquatic or terrestrial, with the exception of Boiga blandingi and Dendroaspis viridis that can be both arboreal and terrestrial, and C. reinhardti that is fossorial. Arboreal species mostly preyed on tree frogs and birds including eggs and nestlings, and the aquatic forms preyed on fish and frogs. Mammals, reptiles and toads constitute the prey items of terrestrial species while fossorial species feed on annelids, molluscs, arachnids, myriapods, hexapods, amphibians, reptiles and mammals. Rev. Biol. Trop. 55 (2): 717-721. Epub 2007 June, 29.

Se registró un total de 25 especies de serpientes en la arboleda de Osun en Osogbo, Nigeria, incluyendo prominentemente dos especies consideradas escasas en el sudoeste de Nigeria: Afronatrix anoscopus y Calabaria reinhardti; Philothamnus semivariegatus, una especie de la sabana, es común posiblemente debido a las actividades de cultivo fuera de la reserva. Junto con las ocho especies abundantes siguientes, A. anoscopus, representó el 69.7 % de la comunidad de serpientes. Las especies dominantes son acuáticas o terrestres, con excepción de Boiga blandingi y Dendroaspis viridis que son arborícolas y terrestres, y C. reinhardti que es fosorial. Las especies fosoriales tienen mayor diversidad trófica.

Are there co-occurrence patterns that structure snake communities in Central Brazil?

The main factors that structure Neotropical animal communities have been the subject of discussion in ecology communities. We used a set of null models to investigate the existence of structure in snake communities from the Cerrado in Central Brazil in relation to the co-occurrence of species and guilds concerning specific resources. We used fragments (conservation units) inside the Distrito Federal and neighbor municipalities. In spite of recent human colonization in the region from the end of the 1950Æs, intense habitat modification and fragmentation has taken place. Sixty three snake species are present in the Distrito Federal. Co-occurrence analysis of species and guilds associated to snake diets and habitats suggested a lack of organization. The homogeneity of habitats in Central Brazil and the minor importance of ecological effects can lead to random arrangement.

Os processos que levam à estruturação de comunidades animais neotropicais têm sido sujeito de ampla discussão em ecologia de comunidades. Usou-se um conjunto de modelos nulos para investigar a existência de estrutura em comunidades de serpentes presentes no Cerrado do Brasil Central, em relação à coocorrência de espécies e de guildas relacionadas a recursos específicos. As localidades utilizadas para as análises representam fragmentos de habitats dentro do Distrito Federal e em municípios vizinhos. Apesar da recente colonização humana da região, datada para o final da década de 50, a intensidade da modificação e fragmentação dos habitats no Brasil Central têm sido enorme. Sessenta e três espécies de serpentes estão presentes no Distrito Federal. As análises dos padrões de coocorrência tanto para as espécies quanto para guildas relativas à dieta e ao uso do ambiente sugeriram ausência de organização. A homogeneidade dos ambientes no Brasil Central e a baixa importância de efeitos ecológicos podem levar ao arranjo randômico.

A importância dos acidentes ofídicos como causa de mortes em bovinos no Brasil / The importance of snake bites as cause of cattle death in Brazil

A revisão da literatura pertinente indica que as opiniões sobre a importância dos acidentes ofídicos, como causa de mortes em bovinos no Brasil, são divergentes no meio veterinário. Enquanto alguns acreditam que são pouco importantes, ou que têm menor significado do que lhes é atribuído, outros são da opinião que esses acidentes são freqüentes. Verificou-se que só foi relatado diagnóstico fundamentado de dois casos fatais de envenenamento por Bothrops spp em bovinos, e de nenhum por Crotalus spp. Um questionário por nós submetido a patologistas e clínicos veterinários que atuam em diversos Estados do país, revelou apenas raros casos suspeitos de envenenamento ofídico fatal em bovinos no Brasil. Em nossas viagens de estudo e nos trabalhos de diagnóstico nunca estabelecemos o diagnóstico de morte por acidente ofídico em bovinos. Os casos tidos como envenenamento ofídico, na sua grande maioria, são apenas suposições, sem embasamento. Esses "diagnósticos", em geral, são feitos à distância dos animais que morreram, à revelia de exame clínico, necropsia e estudo histopatológico. Importante foi a constatação de que, no Brasil, embora algumas serpentes do gênero Bothrops possam, teoricamente, produzir quantidades suficientes de veneno para matar um bovino adulto, em experimentos realizados, apenas Bothrops alternatus foi capaz de levar a morte um dos três bovinos experimentalmente por ela picados; esse animal tinha apenas 279 kg. Já as serpentes do gênero Crotalus poderiam inocular quantidades letais de veneno para bovinos adultos. Mesmo assim, tanto para Bothrops spp, como para Crotalus spp, há que se considerar que as serpentes, em geral, só inoculam parte do veneno disponível. Esse estudo indica que é necessário melhor investigar as mortes suspeitas de terem sido causadas por acidente ofídico em bovinos no Brasil. O estabelecimento do diagnóstico de morte por envenenamento ofídico, porém, só é possível pela determinação precisa do quadro clínico-patológico...

A review of the literature shows that opinions on the importance of snake bites as cause of cattle death in Brazil are divergent among veterinarians; some think they are of no importance or of only minor significance, others are of the opinion that snake bites are frequent. However, the literature only reports two confirmed fatal cases by Bothrops and none by Crotalus in cattle in the country. A questionnaire which was submitted for appraisal to veterinary pathologists and clinicians in various States of Brazil, revealed only suspected cases of fatal accidents by snakes in cattle. During our field and laboratory diagnostic work we never made a diagnosis of a snake bite accident. Many "diagnoses" have apparently been made at a distance from where the animals died, without clinical and post-mortem examination, nor histological studies. By this way, the great majority of cases seems to be only supposition. In Brazil there are only few snakes of the genus Bothrops theoretically able to produce sufficient amounts of venom to kill an adult bovine. Nevertheless, in experiments, only Bothrops alternatus was able to cause the death of just one out of three bovines bitten, and this animal only weighed 279 kg. Snakes of the genus Crotalus can produce sufficient amounts of venom to kill an adult bovine; however it is known, that snakes of the genus Crotalus as well as of Bothrops generally inoculate only a part of their venom. These considerations indicate that the deaths suspected to have been caused by snake bites in cattle in Brazil have to be studied more thoroughly. A diagnosis can only be confirmed by establishing the precise clinical and pathological picture. Our current opinion is that fatal snake bites are much less frequent in cattle than often believed, and that their importance is generally much exaggerated.

Biología reproductiva de la cascabel centroamericana Crotalus durissus durissus (Serpentes: Viperidae)en Costa Rica / Reproductive biology of the Central American rattlesnake Crotalus durissus durissus (Serpentes: Viperidae) in Costa Rica

In Costa Rica, rattlesnakes mate during the early dry season (December and January) and births occur in the early rainy season (May-July). Gestation is therefore about 6 months. The mean number of offspring is 22.9 and is significantly correlated with the size of the female.Newborn rattlesnakes are 27.5-43.0 cm in length and weight 11.4-46.3 g. They are relatively docile. Adult males are longer and heavierthan females. Females seem to have their first litter when their size exceeds 120 cm.

Ciclos reproductivos de la serpiente coral Micrurus nigrocinctus (Serpentes: Elapidae) en Costa Rica / Reproductive cycles of the coral snake Micrurus nigrocinctus (Serpentes: Elapidae) in Costa Rica

The coral snake Micrurus has two reproductive patterns in Costa Rica. Specimens of the Pacific population (m. n. nigrocinctus) mate during the early dry season (November, January). Oviposition takes place in February and March; the mean number of eggs was 7.9 (5-14) in this population. Births occur between April and June after 47-81 days of incubation. The total lenght of neomates is 168-212 mm, and the weight is 1.2-2.0 g. Specimens of the Atlantic population (M. n. mosquitensis) seem to have an extended breeding season. Oviposition in this subspecies was observed in March and June; the mean number of eggs was 6.7 (5-8). Births take place in May and August, after two months of incubation. Neomates have 173-189 mm in total lenght and 1.9-2.4 g in mass. Adult females are longer than males, especially in M. n. mosquitensis.