Bufo Melanostictus Research Articles

Effect of controlled Nickel exposure on Duttaphrynus melanostictus oxidative stress and its management

This study mainly focuses on the effect of a common heavy metal poisoning and how the oxidative stress is managed in Duttaphrynus melanostictus during Nickel poisoning. The subject, Duttaphrynus melanostictus was exposed to Nickel in regular frequency with a very small amount by creating moist environment which imitates the presence of Nickel in soil due to pollution and then the body weight analysis (by ANOVA and Post Hoc analysis (using SPSS package 16.0)) and skin coloration and pigmentation were checked at 24 hours interval to study the oxidative stress and its management by the animal's physiological system. The initial change in skin color at early stages of nickel exposure and then its restoration was observed. Similarly the loss of body weight at initial exposure and then its stabilization after some days was noted. The analysis and observations revealed that the antioxidant system of Duttaphrynus melanostictus is well developed to sustain against the oxidative stress due to nickel exposure.

Abundance, distribution and spread of the invasive Asian toad Duttaphrynus melanostictus in eastern Madagascar

The Asian toad, Duttaphrynus melanostictus, was accidentally introduced to Toamasina (eastern Madagascar) around 2010, and since then has spread at a substantial rate across a larger area. This study documents the expansion of the invasive range of this species, calculates the invasion spread rate, and provides estimates of toad abundance and habitat preferences. Updates of the distribution range revealed a fivefold increase of the invaded area over 3 years, and a doubling of the rate of spread, showing a shift of the invasion towards the North-West, most probably because of the absence of ecological barriers. We used N-mixture models to estimate toad abundance on the basis of repeated count data of six areas in Toamasina and its surrounding countryside. Toad distribution shows heterogeneous density across the distribution range, with an average abundance of 184 toads ha−1 (95% CI 132–263). The toad’s abundance was highest in sites with the presence of organic waste, and was negatively related to the density of road networks in the proximity of study sites. The rapid expansion of the Asian toad in the Toamasina region suggests that this toad is an increasing threat for Madagascar. We propose immediate management actions that could limit the spread of alien toads in this megadiverse country.

Anuran Species in Kayu Tanam Area

There are two types of areas of Kayu Tanam District as highland form Anai Area and as lowland form Kapalo Hilalang. The two types of landform have been accord to frog life span of the anuran. The Anai areas have been an education-tourism area to domestic and international tourism. Koto Hilalang area have been paddy farming area without pesticides treatment. Koto Hilalang have been an education-tourism area to domestic and international tourism too. The aimed of this study to inventory and to comparison the Anuran species in two type's area of Kayu Tanam District. The data were collected using Visual Encounter Survey (VES) method modified by Time Search Method. The result showed that there are 21 species of frogs (Polypedates leucomystax, Polypedates colletti, Polypedates macrotis, Polypedates otilophus, Rhacophorus pardalis, Duttaphrynus melanostictus, Pelophryne signata, Phrynoidis asper, Kalophrynus palmatissimus, Kalophrynus pleurostigma, Microhyla heymonsi, Megophrys nasuta, Limnonectes blythii, Limnonectes kuhlii, Limnonectes malesianus, Occidozyga lima, Occidozyga sumatrana, Fejervarya cancrivora, Fejervarya limnocharis, Hylarana nicobariensis, and Hylarana erythraea) from 12 genera of six families. Only six species (Duttaphrynus melanostictus, Fejervarya cancrivora, Hylarana erythraea, Megophrys nasuta, Occidozyga sumatrana, and Polypedates leucomystax) from 21 species has found in Kapalo Hilalang.

Description of a New Species of Rhabdias Stiles and Hassall, 1905 (Nematoda, Rhabdiasidae) in Duttaphrynus melanostictus (Schneider, 1899) from West Bengal, India

The purpose of this article is to describe a new species of Rhabdias Stiles and Hassall, 1905 from West Bengal, India. Rhabdias bengalensis sp. nov. (Nematoda, Rhabdiasidae) recovered from the lungs of Asian common toad, Duttaphrynus melanostictus (Schneider, 1899), collected from Illambazar town, Birbhum district of West Bengal, India. The collected nematode specimens were clean by shaking them in 0.67% NaCl solution and were killed and fixed in steaming 70% alcohol; lactophenol was used as a mounting medium for light microscopic examination. The lactophenol treated specimens after examination were directly transferred to 70% alcohol and could be stored satisfactorily. The new species is named as, R. bengalensis sp. nov. (Nematoda, Rhabdiasidae), in reference to its locality of collection, West Bengal, India. The worms are small [(2.84-2.96 mm) in length], anterior end somewhat truncated and posterior end tapering. R. bengalensis sp. nov. is characterised by rounded mouth without lips, inflated cuticle, cup-shaped buccal capsule, pre-equatorial vulva and a conical tail. The present nematodes, thus, appear to be new in the field of science and name R. bengalensis sp. nov. is proposed for them. R. bengalensis sp. nov. represents 17th species described from oriental region and the 10th species from India.

Meteterakis asansolensis sp. nov. (Nematoda: Heterakidae) in Duttaphrynus melanostictus (Schneider, 1899) (Amphibia: Anura: Bufonidae) from Asansol coalfield area, Paschim Bardhaman, West Bengal, India.

Meteterakis asansolensis sp. nov. (Nematoda: Heterakidae) recovered from the rectum of Asian common toad, Duttaphrynus melanostictus (Schneider, 1899), collected from Asansol coalfield area in Paschim Bardhaman district of West Bengal, India, is described and illustrated. This species is characterised by the presence of a precloacal sucker, a gubernaculum and two equal and similar spicules (0.31-0.32mm in length). This species differs from other reported species of the Oriental region by morphometrical ranges of measurements of males (3.09-3.54mm) and females (4.60-4.72mm) and the number and the distribution pattern of caudal papillae in males which includes 5 pairs precloacal, 1 pair adcloacal and 5 pairs postcloacal in position.

The Antifungal Activity of Skin Secretion and its Extract of Indian Toad Bufo melanostictus

The Antifungal Activity of Skin Secretion and its Extract of Indian Toad Bufo melanostictus

Food preferences of anuran species in horticultural lands, Doulu village, Karo regency, North Sumatera

Anura is an amphibian group of species with potential as natural pest predator. Data on food preferences and potential anuran species as pest control in horticultural lands at Doulu Village, Karo Regency, North Sumatera has not yet been reported. The aims of this study were to determine the type of food through stomach dissection and to evaluate the role of anuran species as a pest control by calculating percentage of insect pests as their preferred food. The results of this study found four species namely Duttaphrynus melanostictus, Phrynoidis juxtaspera, Fejervarya cancrivora and Hylarana erythraea. The results from stomach dissection found that 25 insect species belonging to 14 orders were preyed by the anuran species. Based on the percentage of insect pests as preferred food, species D. melanostictus was the most potential followed by H. erythraea, F. cancrivora and P. juxtaspera. It can be concluded that all anuran species found in this study acted as pest control in the habitat with different proportions.

Status of herpetofauna in Rupandehi and Arghakhanchi districts, Nepal

Herpetofauna are unique creature which comprise both amphibians and reptiles. The present study was carried out on herpetofaunal diversity in Rupandehi and Arghakhanchi districts. Each of six sampling stations was conducted in the study areas. Ten standardized 10 x 200 m strip transects and 20-25 standard Quadrat sizes of 20 m x 20 m were set in each station. Observed museum specimens and questionnaire survey were also conducted during data collection. A total of 45 spe cies of herpetofauna was recorded with 9 species of amphibians) and 36 species of reptiles. Six species were from the family Ranidae, two species from Bufonidae and one speciesfrom Rhacophoridae. Lizards were represented by 11 species belonging to four different families. Each of Gekkonidae, Agamidae and Scincidae family was represented by 3 species and the Varanidae by two species. The family Crocodylidae was represented by one species. The order Testudines (turtles) was represented by 2 species from family trionychidae and bataguridae. Twenty two species of snakes were recorded from 6 different families. The amphibian species, namely; Euphlyctis cyanophlyctis, Zakerana nepalensis, Bufo melanostictus and B. stomaticusand reptile species Calotes versicolor were relatively abundant. Seven species of amphibians and18 species of reptiles were common in both districts. The study areas were diverse microhabitats due to the elevation from 71 m to 2004 m with plain, Churia and mountain range.

Individual identification of Duttaphrynus melanostictus (Schneider, 1799) (Amphibia: Anura: Bufonidae) based on dorsal wart patterns

The dorsal surface of Duttaphrynus melanostictus is covered with keratinized warts of various sizes and shapes. Using combinations and patterns of cranial and mid dorsal warts, we attempted to identify individual toads from a natural population as a non-invasive alternative to existing marking techniques based on toe clipping, pit tagging, and subcutaneous elastomer injections to facilitate population estimates. An accuracy of 100% identification was achieved via this method, making it a potent tool for population studies in this species that is faster, cheaper and less disruptive than standard marking techniques.

Dietary assessment of five species of anuran tadpoles from northern Odisha, India

Anuran tadpoles are gregarious predators capable of differentiating food items among diverse types of prey via varied feeding and oral structures. Tadpoles were collected from different study sites in three districts of northern Odisha during three consecutive rainy seasons (from July–October of 2015–2017). After morphometric measurements (total length and body length), the stomach contents of 75 tadpoles belonging to five different anuran species (Duttaphrynus melanostictus, Euphlyctis cyanophlyctis, Fejervarya orissaensis, Polypedates maculatus and Microhyla ornata) belonging to four families namely Bufonidae, Dicroglossidae, Rhacophoridae and Microhylidae were examined. The food spectrum of tadpoles included mostly detritus, followed by phytoplankton (represented by 5 classes and 54 genera). Such studies contribute to the understanding of the natural diets of these anuran species that can assist in developing management strategies for them. Aquatic habitats must be conserved and maintained so that conservation of anurans can be ensured.

Indian toad (Bufo melanostictus, Schneider) skin extract induces apoptosis and shows cytotoxic effect on Ehrlich ascites carcinoma (EAC) cells

Indian toad (Bufo melanostictus) skin extract (TSE) was evaluated for cytotoxic and apoptogenic activities on Ehrlich ascites carcinoma (EAC) cells of EAC bearing Swiss albino male mice. LD50 of TSE was found to be 400 mg kg-1, (i.v.) and 750 mg kg-1, (i.p.) in mice. EAC cells (1-2 ´ 105 / mouse) were inoculated (i.p.) into mice (20.6 ± 0.14 gm) and the status of EAC cell proliferation and viability were studied in control and TSE treated groups. TSE (10, 20, 30 mg kg-1 d-1, i.p. for 10 d) significantly inhibit EAC cell growth in dose dependent manner. TSE (50, 100 mg kg-1 d-1, i.p. for 1 d) significantly reduced the viability of EAC cells and decreased the MTT values compared to control cells. TSE induced DNA breakage was reflected in DNA ladder and single cell gel electrophoresis (comet assay). TSE significantly (P<0.001) increased the number tailed cells and length-width ratio of DNA mass in EAC cells as compared to control. Fluorescent microscopy of TSE treated cells showed significant increase in number of early and late apoptotic cells compared to the control EAC cells. Apoptotic index of TSE treated cells was significantly (P<0.001) higher than that of the control cells. Changes in serum LDH, β2-microglobulin in TSE treated EAC mice and our earlier studies indicated the involvement of immunomodulation which may indirectly be associated with the anticancer activity of TSE.
 Keywords: Toad skin extract; Bufo melanostictus; Ehrlich ascites carcinoma; Cytotoxic agent;

Effects of the insecticide chlorpyrifos, on hatching, mortality and morphology of Duttaphrynus melanostictus embryos

In an attempt to assess the effects of chlorpyrifos [O,O-diethyl O-(3,5,6-trichloropyridin-2-yl) phosphorothioate], the second largest selling insecticide in India, studies were made with reference to some non-target organisms. The present study was undertaken to evaluate the effects in the embryos of Duttaphrynus melanostictus caused by the commercial formulations of chlorpyrifos (Tricel, chlorpyrifos, 20% EC). The LC50 value for Duttaphrynus melanostictus embryos after 48 h (h) of treatment with chlorpyrifos was found to be 57.525 ppm. The mortality of the embryo was significantly affected by different concentrations of chlorpyrifos when compared with the control groups. An increase in concentration of chlorpyrifos resulted in the simultaneous decrease of the hatching percentage and an increase in the morphological abnormalities such as compression of the embryo, reduced body size and curling of tail.

Cocktail effect of Profenophos and Abamectin on tadpoles of Asian Common Toad (<i>Duttaphrynus</i> <i>melanostictus</i>)

Farmers mix two or more pesticides as mixing saves the spraying time and the labour cost and also with the idea that it increases the efficiency. The cocktail effect of two agrochemicals, profenophos and abamectin, was tested on the tadpoles of the Asian common toad, Duttaphrynus melanostictus under laboratory conditions. First, the 48 hr lethal concentrations (LC50) was determined. Then, a chronic exposure to a series of ecologically relevant concentrations (profenophos: 0.125, 0.25, 0.5, 1.0, 2.0 ppm and abamectin: 0.01, 0.02, 0.03, 0.04, 0.05 ppm) and a mixture of these were carried out. A control was set up using de-chlorinated tap water. Survival, growth, behaviour and development of malformations were observed until metamorphosis. The LC50 value of profenophos and abamectin were 3.78 ppm and 0.12 ppm, respectively. Both pesticides caused lethal and sub lethal effects at low concentrations while abamectin was more toxic. In the chronic exposure to field level had greatly reduced the survival of tadpoles in profenophos (Chi square test, χ2= 133.8, p = 0.001), abamectin (χ2 = 105.5, p = 0.001) and the cocktail (χ2 = 137.5, p> 0.001) when compared with the control. All the exposures caused a reduction in the growth parameters with a significant reduction in snout-vent length and body mass in 15 days post-hatch tadpoles (one way ANOVA, p = 0.001). Moreover, exposed tadpoles took a longer time to metamorphose (40-42 days), developed malformations and showed behavioural abnormalities like altered feeding and swimming behaviours. Profenophos induced scoliosis and kyphosis, abamectin caused oedema while the cocktail exposed tadpoles developed both scoliosis and oedema. The effects of the cocktail exposure on survival, growth and development of malformations were higher than the lone effects. Although pesticide cocktail may have potential benefits in pest resistance management, what chemicals to be mixed have to be studied before recommending the mixing of chemicals to farmers to minimize the harmful effects on the environment.

Biochemical Analyses of Proteins from Duttaphrynus melanostictus (Bufo melanostictus) Skin Secretion: Soluble Protein Retrieval from a Viscous Matrix by Ion-Exchange Batch Sample Preparation.

A crucial step in scientific analysis can be sample preparation, and its importance increases in the same rate as the sensitivity of the following employed/desired analytical technique does. The need to analyze complex, viscous matrices is not new, and diverse approaches have been employed, with different success rates depending on the intended molecules. Solid-phase extraction, for example, has been successfully used in sample preparation for organic molecules and peptides. However, due to the usual methodological conditions, biologically active proteins are not successfully retrieved by this technique, resulting in a low rate of protein identification reported for the viscous amphibian skin secretion. Here we describe an ion-exchange batch processing sample preparation technique that allows viscous or adhesive materials (as some amphibian skin secretions) to be further processed by classical liquid chromatography approaches. According to our protocol, samples were allowed to equilibrate with a specific resin that was washed with appropriated buffers in order to yield the soluble protein fraction. In order to show the efficiency of our methodology, we have compared our results to classically prepared skin secretion, i.e., by means of filtration and centrifugation. After batch sample preparation, we were able to obtain reproductive resolved protein chromatographic profiles, as revealed by SDS-PAGE, and retrieve some biological activities, namely, hydrolases belonging to serine peptidase family. Not only that, but also the unbound fraction was rich in low molecular mass molecules, such as alkaloids and steroids, making this sample preparation technique also suitable for the enrichment of such molecules.

Uji Aktivitas Senyawa Antibakteri Katak Papua (ANTIBACTERIAL ACTIVITY TEST OF PAPUAN FROGS)

Skin and submental glands of Papuan frogs have antibacterial compounds‘ which were capable to impede growth of tested bacteria based on diffusion method. These frogs were Platymantis papuensis, Litoria infrafrenata, Bufo melanostictus, Rana grisea and Rana sp., and the tested bacterial were the positive Gram bacteria (Staphylococcus aereus, and Bacillus subtilis) and the negative Gram bacteria (Escherichia coli and Pseudomonas aeroginosa). Skin frog which extracted with hot water (100oC) showed antibacterial activity which significantly impeded the growth of tested bacteria using diffusion method.

Molecular mechanisms underlying the antimetastatic activity of bufalin.

Bufalin is a monomer compound extract from Chansu, which is a traditional Chinese medicine obtained from the skin and parotid venom glands of toads, such as Bufo bufo gargarizans Cantor and Bufo melanostictus Schneider. Chansu had been used in traditional Chinese medicine for >1,000 years due to its cardiac, anti-inflammatory and anticancer properties. Previous studies identified bufalin as the main anticancer compound of Chansu, and recent evidence has corroborated its anticancer properties. Bufalin inhibits cancer cell proliferation, induces cell cycle arrest, induces cancer cell apoptosis, inhibits neovascularization, induces cell differentiation, inhibits cancer metastasis and invasion, and enhances chemotherapeutic drug sensitivity. However, the function and mechanism of bufalin in metastatic cancer cells have not yet been expounded. The aim of the present review was to discuss the recent progress and prospects of bufalin in the prevention of cancer metastasis, particularly in inhibiting epithelial-to-mesenchymal transition.

Habitat preference based on herpetofauna spatial distribution in Coal Mining Area of PT Singlurus Pratama, East Kalimantan

Herpetofauna communities are formed due to the suitability of the habitat or adaptation process that forces a species to survive. The opening of the land mines result in missing or changing the habitat of herpetofauna. This research was conducted to know the preferences of the herpetofauna of habitat based on spatial distribution of herpetofauna in the vicinity of mining area of PT Singlurus Pratama. The survey was conducted in the area of revegetasi, forest fragmentation, the district adjacent to the mining area, rivers and water spots or natural and man-made on two mining blocks i.e. block Pearl and block independence. The method of election of purposive sampling location with direct search survey methods (Visual Encounter Surveys). The main species found 4 that its spread most widely with populations high. The most frequent species of herpetofauna and many found among others: Eutropis multifasciata, Enhydris enhydris, Fejervarya cancrivora, Polypedates leucomystax and Duttaphrynus melanostictus. Based on the value of the index indicates that the diversity of herpetofauna communities distress with low. Types of herpetofauna more land cover found in the undergrowth, secondary forest and agricultural areas that there are sources of water in it.

Atypical assortative mating based on body size in an explosive-breeding toad from a tropical island of southern China

Mating patterns exhibit considerable intra- and interspecific variation. Sexual selection can lead to the occurrence of random and assortative mating in different populations of the same species. Thus, understanding variation in mating decisions is crucial to understanding variation in the direction of sexual selection. We investigated natural mating patterns in Black-spectacled toads (Duttaphrynus melanostictus), an explosive-breeding species that breeds throughout the year. We captured amplectant pairs (137) and non-amplectant males (212) during breeding seasons from November 2016 to April 2017 in tropical-island population of southern China. Our study found no significant difference in snout-vent length (SVL) between amplectant and non-amplectant males. Female and male SVL were positively correlated with each other. Small females were paired more frequently with small males, less frequently with large males, but had no preference for or against medium males. Medium females exhibited no preference. Large females showed no preference for large males, but were paired less frequently with small males. These data suggested that successful amplectant males had body sizes representative of the entire population. Both random and size-assortative mating were present simultaneously in the same population and within the same breeding season. Female choice was important in shaping the mating behavior of Black-spectacled toads, promoting genotype-frequency stabilization and body-size diversity in the population.

Signals of forest degradation in the demography of common Asian amphibians.

BackgroundLowland areas in tropical East and Southeast Asia have a long history of conversion from forestland to agricultural land, with many remaining forests being chronically degraded by wood cutting, livestock grazing, and burning. Wetland-breeding amphibians that have evolved in lowland forests in the region have adjusted to changes in habitat composition caused by humans’ activities, and populations continue to persist. However, we have little understanding of the impacts of forest disturbance on these species beyond assessments of abundance and distribution, and species considered to be common and widespread have been largely neglected.MethodsWe examined body condition and sex ratios of toads (Duttaphrynus melanostictus), predation risk in treefrogs (2 Polypedates spp.), and growth and survival of leaf litter frogs (2 Microhyla spp.) in agricultural land, degraded forest, and intact forest in two study areas, Thailand and Hong Kong.ResultsToad populations exhibited higher body condition and female-biased sex ratios in intact forest. Predation of treefrog embryos by flies was lower in intact and degraded forests than in agricultural land. Embryonic survival and larval growth and survival in leaf litter frogs were lower in intact forests than in agricultural land. Results for each study were similar between study areas.DiscussionFor three of five of these common amphibian species, we documented signals of forest loss and disturbance in their populations. Although these species occur in disturbed habitats, loss of forest cover continues to degrade aspects of their population demography. We urge conservation biologists to consider that populations of species appearing to be common, widespread, and tolerant of human disturbance may be eroding over time.

Mating Calls of Selected Sarawak Toads (Amphibia: Anura: Bufonidae)

The sound produced by the anurans including toads can be a survival strategy for the selection of fittest males by their conspecific females and a form of effective prezygotic mechanism. Most of the published works on anuran sound production were on true frogs or ranids, yet little is known about sound characteristics of toads. Here we describe the properties of mating calls from six selected toad species from six study sites in Sarawak. Males’ mating calls were recorded and analyzed using SoundRuler Acoustic Analysis ver 0.9.6.0. Call characteristic were subsequently compared for toad species differentiation. The results showed that each species differ in call characteristics, with pulsating note, rate of note repetition and pitch being the most apparent characters. The highest number of pulse notes belongs to Duttaphrynus melanostictus while Ansonia spinulifer exhibited highest pitch and rate of note repetition. These species’ differences in mating call characteristics provide an additional method for anuran species classification besides morphological and molecular DNA data. It is also a very useful guide during field survey as the sound is audible and identification can be made without the need of capturing the toads.