Rana Hexadactyla Research Articles

Phylogenetic relationships of two species of Haematoloechus (Trematoda: Haematoloechidae) infecting Euphlyctis spp. from the biodiversity hotspot, Western Ghats, India.

During a parasitological survey in the biodiversity hotspot, two species of the digenetic trematode, Haematoloechus from the lungs of Indian skipper frog Euphlyctis cyanophlyctis and the Indian green frog, E. hexadactylus inhabiting the biodiversity hotspot, Western Ghats, India, were found and described using morphological and molecular tools. Morphological examinations indicated that the two species are Haematoloechus almorai Pande, 1937 and H. (H.) variegatus capyristes (Klein, 1905; Ingles, 1932) Odening, 1958 as previously described in the original manuscripts but with some morphological differences. The ITS region (ITS1, 5.8S and ITS2) and 28S gene of ribosomal DNA sequences were performed for phylogenetic studies showed that the sequences of these species did not match with any of the previously reported sequences on GenBank database. Phylogenetic analysis placed H. almorai and H. (H.) variegatus capyristes in a well-supported clade under the genus Haematoloechus. This is the first molecular study of present Haematoloechus species from the Western Ghats, India and discussed their phylogenetic position.

COMPARATIVE STUDY ON ECOLOGY AND BREEDING BEHAVIOUR OF TWO ANURAN SPECIES OF RANID (EUPHLYCTIS HEXADACTYLUS) AND RHACOPHORID (POLYPEDATES MACULA TUS) IN NORTH ODISHA

Ranids are restricted to permanent ponds rich with hydrophytes or thick vegetation. Polypedates maculatus is arboreal in nature and frequently hided near human habitation. Euphlyctis hexadactylus is restricted to permanent ponds rich with hydrophytes which are the major source of food for the species. Ranid amplecting pairs move and eggs are laid in scattered manner and adhered to aquatic plants. Foam nest in rhacophorid is adhered to twigs above the water level. Smallest female of Euphlyctis hexadactylus have more number of eggs than some larger female. There is lack of correlation between body size and clutch size. The snout vent lenght (SVL) is not a key determining factor for clutch size in case of Ranid species but in case of rhacophorid the number of eggs in a clutch increases with increase size of the female. Variation in pigmentation or characteristic colouration are observed in tadpoles of ranid and rhacophorid.

Cytogenotoxicity evaluation of a heavy metal mixture, detected in a polluted urban wetland: Micronucleus and comet induction in the Indian green frog (Euphlyctis hexadactylus) erythrocytes and the Allium cepa bioassay

Heavy metal contamination in wetland ecosystems is a serious environmental and health concern. This study evaluated the cytogenotoxicity of a previously evidenced heavy metal contamination (Cd, Cr, Cu, Pb and Zn ∼5 ppm each) in a polluted urban wetland, the Bellanwila-Attidiya sanctuary (BAS) in Sri Lanka, using a battery of cytogenotoxic assays. Micronucleus and comet assays evaluated the genotoxicity in erythrocytes of a common amphibian, the Indian green frog (Euphlyctis hexadactylus), under natural metal exposure in the wetland, and in vitro exposure, respectively.The Allium cepa bioassay assessed the cytogenotoxicity of the heavy metal mixture and of the individual metals, under laboratory exposure. Although in vivo natural exposure showed no significant induction of micronuclei in frog erythrocytes (P > 0.1), a significant and dose dependent elevation of comets was evident with in vitro exposure to the metal mixture (P < 0.001). Field controls did not show significant impacts in the A. cepa bioassay, whereas individual exposure to heavy metals reported lower effects than their combined exposure under laboratory conditions; Pb2+was the most toxic metal, with the highest mitotic inhibition (Pb2+>Cd2+>Zn2+>Cr6 >Cu2+), mutagenic potential as evaluated in the percentage incidence of chromosomal aberrations (Pb2+> Zn2+> Cu2+> Cr6+> Cd2+) and cytotoxicity evaluated by the incidence of cell apoptosis and necrosis (Pb2+>Cr6+>Cu2+>Cd2+>Zn2+). Thus, the test battery of micronucleus, comet and A. cepa assays that reveal differential aspects of cytogenotoxicity may serve as a valuable tool in environmental monitoring, primarily to screen for complex environmental mixtures of heavy metals that may impact ecological health.

Antidiuretic hormone effect on transport of non-charged solutes (urea and glycerol) across the epithelium

Background: The frog skin epithelium is used as a model to demonstrate the transport of various charged and non-charged solutes from the mucosal to serosal side through channels and transporters. The mucosal side, otherwise termed as the apical side or outer side, is the side which is exposed to the external environment (towards pond water). The serosal side, also known as the basolateral side, faces the internal environment of the organism. Aims and Objectives: The objective of the present study is to determine the action of antidiuretic hormonal (ADH) on the movement of non-charged solutes such as urea and glycerol across the frog skin epithelium. Materials and Methods: For this study, the ventral abdominal skin of frog, species Rana hexadactyla was mounted in an Ussing’s type chamber. Normal Ringer’s solutions containing urea (5 mM) and glycerol (90 mM) each were placed on the mucosal side, and ADH was added either on the mucosal side or the serosal side. After the addition of ADH, the colorimetric method was used to measure the transport of urea at the absorbance of 540nM and glycerol absorbance of 505 nM using a spectrophotometer; statistical analysis was done by Wilcoxon-Signed Ranks Test, all values were expressed as a mean ± standard error of means, n = 4. Results: Addition of ADH (40 nM) on serosal side increased the urea transport from control 29.3 ± 5.1 μmol/dL to 52.3 ± 6.8 μmol/dl and increased glycerol transport from 34.8 ± 6.0 μmol/dL to 45.3 ± 6.6 μmol/dL, whereas addition of ADH on the mucosal side did not increase the glycerol transport, the control value was 14.6 ± 4.3 μmol/dL and with ADH that the value was 9.6 ± 2.9 μmol/dL. Conclusion: The results concluded that the addition of ADH on serosal side enhanced the transport of urea and glycerol. Addition of ADH on the mucosal side did not show any effect on transport of glycerol.

Heavy metal-induced toxicity in the Indian green frog: Biochemical and histopathological alterations.

Heavy metal contamination may have adverse effects on wetland biota, particularly on amphibians. Severe immunotoxic effects elicited in Euphlyctis hexadactylus (Indian green frog) because of metal exposure (Cd, Cr, Cu, Pb, and Zn) in the Bellanwila-Attidiya Sanctuary, a polluted urban wetland in Sri Lanka, provided the rationale for the present study. We evaluated the biochemical and histopathological effects of this metal contamination with a reference E. hexadactylus population and a laboratory exposure group that was subjected to 28 d of exposure to a mixture of Cd, Cr, Cu, Pb, and Zn (5 ppm in each mixture). A histopathological scoring for the semiquantification of tissue damage was established. Results of the biochemical and histopathological markers were remarkably consistent between the 2 exposure scenarios, providing validation for the heavy metal exposure hypothesis. Damage to liver, kidney, lung, and skin of metal-exposed E. hexadactylus quantified multiple impairments absent in the reference frogs. Liver injuries complemented significantly elevated aspartate transaminase (AST), alanine transaminase (ALT), γ-glutamyl transferase (γ-GT), and alkaline phosphatases in frog liver homogenate, indicating hepatocellular leakage and loss of functional and structural integrity of the hepatocyte membrane in both field- and laboratory-exposed frogs. Significant elevation of Kupffer cell hypertrophy, pigmentation, inflammatory cell infiltrates and hepatic inflammation, extramedullary hematopoiesis, karyocytomegaly of hepatocytes (p < 0.05) of the liver, and degeneration of epithelia and necrosis of the lung, manifested as impairments in both metal exposure scenarios. Significantly reduced serum total protein and albumin and significantly elevated urea and creatinine in metal-exposed frogs were indicative of hepatic and renal dysfunction, respectively. The present study affirms histopathology-related biochemical alterations as potential biomarkers for heavy metal toxicity in amphibians. Environ Toxicol Chem 2017;36:2855-2867. © 2017 SETAC.

Heavy metal mediated innate immune responses of the Indian green frog, Euphlyctis hexadactylus (Anura: Ranidae): Cellular profiles and associated Th1 skewed cytokine response

Immune cell and cytokine profiles in relation to metal exposure though much studied in mammals has not been adequately investigated in amphibians, due mainly to lack of suitable reagents for cytokine profiling in non-model species. However, interspecies cross reactivity of cytokines permitted us to assay levels of IFNγ, TNFα, IL6 and IL10in a common anuran, the Indian green frog (Euphlyctis hexadactylus), exposed to heavy metals (Cd, Cr, Cu, Zn and Pb, at ~5ppm each) under field and laboratory settings in Sri Lanka. Enumeration of immune cells in blood and melanomacrophages in the liver, assay of serum and hepatic cytokines, and Th1/Th2 cytokine polarisation were investigated.Immune cell counts indicated overall immunosuppression with decreasing total WBC and splenocyte counts while neutrophil/lymphocyte ratio increased with metal exposure, indicating metal mediated stress. Serum IL6 levels of metal exposed frogs reported the highest (~9360pg/mL) of all cytokines tested. Significantly elevated IFNγ production (P<0.05) was evident in heavy metal exposed frogs. Th1/Th2 cytokine ratio in both serum and liver tissue homogenates was Th1 skewed due to significantly higher production of pro-inflammatory cytokines, IFNγ in serum and TNFα in the liver (P<0.01).Metal mediated aggregations of melanomacrophages in the liver were positively and significantly (P<0.05) correlated with the hepatic expression of TNFα, IL6 and IL10 activity. Overall, Th1 skewed response may well be due to oxidative stress mediated nuclear factor κ-light chain enhancer of activated B cells (NFκB) which enhances the transcription of pro-inflammatory cytokines. Xenobiotic stress has recently imposed an unprecedented level of threat to wildlife, particularly to sensitive species such as amphibians. Therefore, understanding the interactions between physiological stress and related immune responses is fundamental to conserve these environmental sentinels in the face of emerging eco-challenges.

First report of Seuratascaris numidica Seurat, 1917 (Nematoda: Ascarididae) and other helminths from amphibians of West Bengal, India.

Studies on nematode parasites from anuran hosts from Eastern India, particularly West Bengal, are rare. To our knowledge, there is a report of larvae of Monhysterides sp. (a fish parasite) from cysts within the body cavity and musculature of Duttaphrynus melanostictus, Hoplobatrachus tigerinus and Euphlyctis hexadactylus as well as descriptions of Aplectana duttaphryni from D. melanostictus, Aplectana dubrajpuri from H. tigerinus, Cosmocerca microhylae from Microhyla rubra and Rhabdias bulbicauda from D. melanostictus. Here, we report mature individuals of typical anuran parasites, Diplodiscus amphichrus and Seuratascaris numidica, from H. tigerinus and larvae of Acuariidae (a bird parasite) from Fejervarya limnocharis collected in Kulti, West Bengal.

Characterization and evolution of the mitochondrial DNA control region in Ranidae and their phylogenetic relationship.

The control region is considered to be one of the most variable parts of animal mitochondrial DNA (mtDNA). We compared the mtDNA control region from 37 species representing 14 genera and 4 subfamilies of Ranidae, to analyze the evolution of the control region and to determine their phylogenetic relationship. All the Ranidae species had a single control region, except four species that had two repeat regions. The control region spanned the region between the Cyt b and tRNAleu genes in most of the Ranidae species. The length of the control region sequences ranged from 1186 bp (Limnonectes bannaensis) to 6746 bp (Rana kunyuensis). The average genetic distances among the species varied from 1.94% (between R. chosenica and R. plancyi) to 113.25% (between Amolops ricketti and Euphlyctis hexadactylus). The alignment of three conserved sequence blocks was identified. However, conserved sequence boxes F to A were not found in Ranidae. A maximum likelihood method was used to reconstruct the phylogenetic relationship based on a general time reversible + gamma distribution model. The amount of A+T was higher than G+C across the whole control region. The phylogenetic tree grouped members of the respective subfamilies into separate clades, with the exception of Raninae. Our analysis supported that some genera, including Rana and Amolops, may be polyphyletic. Control region sequence is an effective molecular mark for Ranidae phylogenetic inference.

Report on Green Frog (Euphlyctis hexadactylus) from Vengaivasal Lake (Tamilnadu, India)

Abstract Through the Visual Encounter Survey only one species of green frog (Euphlyctis hexadactylus) was encountered. As we lack previous data we cannot comment on the decline of the species. Frogs, known for specific habitats, are under threats if such habitats are lost. The physico-chemical parameters estimated along with the anuran survey reported that the quality of the lake is not congenial to support the tadpoles of the frogs. The adults can move away from water and survive on land. The habitat, as well as the surrounding wetland, plays a vital role to support a good quantum of anurans.

Heavy metal mediated immunomodulation of the Indian green frog, Euphlyctis hexadactylus (Anura:Ranidae) in urban wetlands

Impacts of heavy metal toxicity on the immune system of the Indian green frog, Euphlyctis hexadactylus, in Bellanwila Attidiya, an urban wetland polluted with high levels of heavy metals, compared to the reference site in Bolgoda, in Sri Lanka was investigated. Significantly higher accumulation of selected heavy metals, copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) were detected by AAS in frog liver and gastrocnemius muscle, in the polluted site than in the reference site. Non-functional immunotoxicity tests; total WBC, splenocyte and bone marrow cell counts, spleen weight/body weight ratio, neutrophil/lymphocyte ratio and basal immunoglobulin levels, and phagocytic capacity of peritoneal macrophages (immune functional test) were carried out using standard methodology. Test parameters recorded significantly lower values for frogs of the polluted site compared with their reference site counterparts, indicative of lowered immune response of frogs in the former site. In vitro phagocytic assay based on NBT dye reduction, measured the stimulation index (SI) of E. hexadactylus blood leukocytes, splenocytes and peritoneal macrophages, where SIs of frogs in the polluted site were significantly lower. Also, in vitro exposure of frog phagocytes to Cu, Zn, Pb and Cd at 10−2–10−10M, showed immunomodulation i.e. low concentrations stimulated phagocytosis while increased concentrations showed a trend towards immunosuppression. IC50 values indicated Cd>Zn>Cu>Pb as the decreasing order of the potential of phagocytosis inhibition. In conclusion, this study clearly demonstrated immunomodulation of E. hexadactylus, stimulated by heavy metals. In-vitro studies evidently suggested the use of phagocytosis as a biomarker in Ecoimmunotoxicology to detect aquatic heavy metal pollution.

Evaluation of Dietary Formulation of Vitellaria paradoxa and Rana Headactyla Oils on Albino Rats

Evaluation of Dietary Formulation of Vitellaria paradoxa and Rana headactyla Oils on Albino Rats This study is aimed at evaluating the effect of dietary formulation of both crude and refined sheabutter (Vitellaria paradoxa) and frog (Rana hexadactyla) oils on laboratory rats. Both crude and refined oil samples were initially analyzed for their physico-chemical properties reported as follows; table 1 presents the changes in the physicochemical of both CSO and CFO with refining. The RI was high in RSB (1.470) against CSO (1.4690) and was similar to RFO (1.4680). A similar trend was observed in FFA (mg NaOH/g) where CSO (2.188) while RSB (0.112) and CFO (3.891) against RFO (0.954). The results also showed a reduction in SV (mg KOH/g) in CSO (246.84) to RSB (109.40) and CFO (280.50) to RFO (175.31). The PV (meQ/g) presented a decrease from CSO (7.30) to RSB (2.50) and from CFO (7.40) to RFO (2.00). The final part of the results presented the IV (meQ/g) for CSO (72.00), RSB (54.00) and CFO (37.00) reduced to RFO (32.00).Similarly, the feed formulations were done using standard method and thereafter a pathological study was carried out on the organs.

Effects of Evans Blue and Amiloride on Anti-Diuretic Hormone (ADH)-Induced Sodium Transport Across Frog (Rana hexadactyla) Skin

The epithelial sodium channel (ENaC) has four subunits, namely α (alpha), β (beta), γ (gamma) and δ (delta). The functional ENaC is formed by the combination of either αβγ or δβγ subunits. The aim of the present study is to determine the combination of ENaC subunits predominant on the apical side of the frog skin, and the effect of ADH on sodium transport though these two ENaCs subunit combinations. The ventral abdominal skin of the frog, Rana hexadactyla was mounted in an Ussing-type chamber. The voltage-clamp method was performed to measure the ionic transport across the frog skin with normal Ringer solution (NR) on both sides. Evans blue (300 µM) and amiloride (100 µM) were added to the NR on the apical side and ADH (40 nM) was added on the serosal side. Statistical significance was analyzed by Student's paired t-test and repeated-measures ANOVA, P < 0.05 was considered significant. This study suggests that the ENaC of the frog skin consist of both αβγ and δβγ subunit combinations on the apical side. Though both types of subunit combination are present, the αβγ type was found to be more common than δβγ. ADH increases the sodium transport across the frog skin. The effect of ADH on sodium transport is achieved through the combination of δ-subunits, not through the combination of a-subunits in the skin of Pana hexadactyla.

Purification, Characterization, and Chemical Modification of Neurotoxic Peptide from Daboia russelii Snake Venom of India

Comprehensive knowledge of venom composition is very important for effective management of snake envenomation and antivenom preparation. Daboia russelii venom from the eastern region of India is the most neurotoxic among the four venom samples investigated. From the eastern D. russelii venom sample, neurotoxic peptide has been purified by combined method of ion exchange gel permeation chromatography and reversed phase high performance liquid chromatography. Molecular weight of Daboia neurotoxin III (DNTx-III) found to be 6,849 Da (as measured on matrix-assisted laser desorption/ionisation-time of flight mass spectrometer), and N-terminal amino acid sequences is I K C F I T P D U T S Q A. Approximate LD50 dosage was 0.24 mg/kg body weight. It produced concentration- and time-dependent inhibition of indirectly stimulated twitches of Rana hexadactyla sciatic nerve gastrocnemius muscle preparations. Chemical modification of DNTx-III tryptophan residue(s) reduced the twitch height inhibition property of toxin, signifying the importance of tryptophan residues for the neurotoxic function. This type of neurotoxic peptide is unique to east Indian regional D. russelii venom.

Anurans of Bhitarkanika mangroves, Odisha, east coast of India

Anurans of Bhitarkanika National Park, the second largest viable mangrove ecosystem measuring 141.44 km2 on the east coast of India, are understudied. This paper presents a comprehensive list of anuran species encountered in and around the protected area. Visual Encounter Surveys during the rainy and winter season in four sites yielded a total of 14 species belonging to five families. Of these, eight species were new records from Bhitarkanika National Park, belonging to the families Bufonidae (Duttaphrynus stomaticus), Dicroglossidae (Euphlyctis hexadactylus, Fejervarya cancrivora, Fejervarya syhadrensis, Hoplobatrachus crassus, Sphaerotheca rolandae), Microhylidae (Microhyla ornata) and Ranidae (Hylarana tytleri). Sightings of Sphaerotheca rolandae, Hylarana tytleri and Duttaphrynus stomaticus were very few in number. All other species found were well represented throughout the study area. Scope for future suggested studies is emphasized.

Local Anesthetic Effect of Citrullus colocynthis on Rana hexadactyla

Local Anesthetic Effect of Citrullus colocynthis on Rana hexadactyla

Complete mitochondrial genomes and novel gene rearrangements in two dicroglossid frogs, Hoplobatrachus tigerinus and Euphlyctis hexadactylus, from Bangladesh

We determined the complete nucleotide sequences of mitochondrial (mt) genomes from two dicroglossid frogs, Hoplobatrachus tigerinus (Indian Bullfrog) and Euphlyctis hexadactylus (Indian Green frog). The genome sizes are 20462 bp in H. tigerinus and 20280 bp in E. hexadactylus. Although both genomes encode the typical 37 mt genes, the following unique features are observed: 1) the ND5 genes are duplicated in H. tigerinus that have completely identical sequences, whereas duplicated ND5 genes in E. hexadactylus possessed dissimilar substitutions; 2) duplicated control region (CR) in H. tigerinus has almost identical sequences whereas single control region (CR) was found in E. hexadactylus; 3) the tRNA-Leu (CUN) gene is translocated from the LTPF tRNA cluster to downstream of ND5-1 in H. tigerinus, and the tRNA-Pro gene is translocated from the LTPF tRNA cluster to downstream of CR in E. hexadactylus; 4) pseudo tRNA-Leu (CUN) and tRNA-Pro genes are observed in E. hexadactylus; and 5) two tRNA-Met genes are encoded in both species, as observed in the previously reported dicroglossid mt genomes. Almost all observed gene rearrangements in H. tigerinus and E. hexadactylus can be explained by the tandem duplication and random loss model, except translocation of tRNA-Pro in E. hexadactylus. The novel mt genomic features found in this study may be useful for future phylogenetic studies in the dicroglossid taxa. However, the mt genome with interesting features found in the present study reveal a high level of variation of gene order and gene content, inspiring more research to understand the mechanisms behind gene and genome evolution in the dicroglossid and as well as in the amphibian taxa in future studies.

Actions of antidiuretic hormone analogues on intact and nystatin‐permeabilized frog skins

The roles of two antidiuretic hormone analogues, namely arginine vasotocin (AVT) and lysine vasopressin (LVP), in solute transport across the ventral abdominal skin of frogs (Rana hexadactyla) were studied using voltage-clamp methods on intact and nystatin-permeabilized preparations. Arginine vasotocin (40 nm), the amphibian analogue of antidiuretic hormone, did not have any effect on the skin of Rana hexadactyla. However, LVP, the porcine antidiuretic hormone, increased the transepithelial potential difference (TEPD) and short-circuit current (SCC) significantly, without affecting the slope conductance. Lysine vasopressin had no action subsequent to addition of amiloride (100 microm) on the apical side or ouabain (10 microm) on the basolateral side. Lysine vasopressin increased slope conductance in the nystatin-permeablized skin while decreasing TEPD. Such a change was not seen in chloride-free solutions. To elucidate the mechanism of action of LVP on intact skin, experiments were done with forskolin and a V(2) receptor blocker. The effects of forskolin (10 microm) were different from those of LVP in that forskolin significantly increased SCC and conductance of the intact skin, while decreasing TEPD. The forskolin-induced increase in conductance was not abolished by amiloride. Use of the V(2) receptor blocker inhibited the effects of LVP. We conclude that AVT does not have an action on the skin of Rana hexadactyla. Lysine vasopressin enhances transepithelial sodium transport by increasing sodium-potassium pump activity, while not affecting the epithelial sodium channel conductance. Lysine vasopressin also enhances an inward-directed conductance on the basolateral membrane, probably a chloride conductance. The action of LVP on the intact frog skin is through the V(2) receptors; however, downstream signalling does not seem to be mediated by cAMP. Analysis of the electrophysiological model of frog skin with LVP allows us additionally to conclude that modulation of channel activity and not carrier-mediated transport affects slope conductance.

Genetic divergence and evolutionary relationships in six species of genera Hoplobatrachus and Euphlyctis (Amphibia: Anura) from Bangladesh and other Asian countries revealed by mitochondrial gene sequences

To elucidate the species composition, genetic divergence, evolutionary relationships, and divergence time of Hoplobatrachus and Euphlyctis frogs (subfamily Dicroglossinae, family Ranidae) in Bangladesh and other Asian countries, we analyzed the mitochondrial Cyt b, 12S, and 16S rRNA genes of 252 specimens. Our phylogenetic analyses showed 13 major clades corresponding to several cryptic species as well as to nominal species in the two genera. The results suggested monophyly of Asian Hoplobatrachus species, but the position of African Hoplobatrachus occipitalis was not clarified. Nucleotide divergence and phylogenetic data suggested the presence of allopatric cryptic species allied to Euphlyctis hexadactylus in Sundarban, Bangladesh and several parapatric cryptic species in the Western Ghats, India. The presence of at least two allopatric cryptic species among diverged Euphlyctis cyanophlyctis in Bangladesh, India, and Sri Lanka was also suggested. In some cases, our estimated divergence times matched the paleogeological events of South and Southeast Asian regions that may have led to the divergence of Hoplobatrachus and Euphlyctis taxa. Especially, land formation at Bangladesh (15–10 Ma) may have allowed the spread of these frog taxa to Southeast Asian areas, and the aridification of central India (5.1–1.6 Ma) might have affected the gene flow of widely distributed species. The present study revealed prior underestimation of the richness of the amphibian fauna in this region, indicating the possible occurrence of many cryptic species among these groups.

Mass Seed Production Technology of Green Frog, Rana hexadactyla Lesson by Captive Breeding

Mass Seed Production Technology of Green Frog, Rana hexadactyla Lesson by Captive Breeding

Genotoxicity of some sulfur dyes on tadpoles (Rana hexadactyla) measured using the comet assay

This report presents the results of a genotoxicity study to evaluate the DNA damage caused by four sulfur dyes used in the textile and tannery industries. Alkaline single-cell gel electrophoresis assay (SCGE) was performed on erythrocytes from Rana hexadactyla tadpoles following whole-body exposure to increasing concentrations of the dyes. The dyes, along with their active ingredients, were Sandopel Basic Black BHLN, Negrosine, Dermapel Black FNI, and Turquoise Blue. The dye-treated tadpoles showed significant DNA damage, measured as mean DNA length:width ratio, when compared with unexposed control animals. Among the four tested dyes Sandopel Basic Black BHLN appears to be highly genotoxic, Dermapel Black FNI was least genotoxic, and Negrosine and Turquoise Blue were moderately toxic to R. hexadactyla tadpoles. The tadpoles showed a significant reduction in DNA damage when placed in dechlorinated tap water after exposure for a 24-hr period to the dye solutions.