WorldWideScience

Sample records for bullfrog rana catesbeiana

  1. Body size affects the predatory interactions between introduced American Bullfrogs (Rana catesbeiana) and native anurans in China: An experimental study

    Science.gov (United States)

    Wang, Y.; Guo, Z.; Pearl, C.A.; Li, Y.

    2007-01-01

    Introduced American Bullfrogs (Rana catesbeiana) have established breeding populations in several provinces in China since their introduction in 1959. Although Bullfrogs are viewed as a potentially important predator of Chinese native anurans, their impacts in the field are difficult to quantify. We used two experiments to examine factors likely to mediate Bullfrog predation on native anurans. First, we examined effects of Bullfrog size and sex on daily consumption of a common Chinese native (Rana limnocharis). Second, we examined whether Bullfrogs consumed similar proportions of four Chinese natives: Black-Spotted Pond Frog (Rana nigromaculata), Green Pond Frog (Rana plancyi plancyi), Rice Frog (R. limnocharis), and Zhoushan Toad (Bufo bufo gargarizans). We found that larger Rana catesbeiana consumed more R. limnocharis per day than did smaller R. catesbeiana, and that daily consumption of R. limnocharis was positively related to R. catesbeiana body size. When provided with adults of four anurans that differed significantly in body size, R. catesbeiana consumed more individuals of the smallest species (R. limnocharis). However, when provided with similarly sized juveniles of the same four species, R. catesbeiana did not consume any species more than expected by chance. Our results suggest that body size plays an important role in the predatory interactions between R. catesbeiana and Chinese native anurans and that, other things being equal, smaller species and individuals are at greater risk of predation by R. catesbeiana. Copyright 2007 Society for the Study of Amphibians and Reptiles.

  2. The emerging amphibian pathogen Batrachochytrium dendrobatidis globally infects introduced populations of the North American bullfrog, Rana catesbeiana

    OpenAIRE

    Trenton W J Garner; Perkins, Matthew W.; Govindarajulu, Purnima; Seglie, Daniele; Walker, Susan; Cunningham, Andrew A.; Fisher, Matthew C

    2006-01-01

    Batrachochytrium dendrobatidis is the chytridiomycete fungus which has been implicated in global amphibian declines and numerous species extinctions. Here, we show that introduced North American bullfrogs (Rana catesbeiana) consistently carry this emerging pathogenic fungus. We detected infections by this fungus on introduced bullfrogs from seven of eight countries using both PCR and microscopic techniques. Only native bullfrogs from eastern Canada and introduced bullfrogs from Japan showed n...

  3. New Trends on Antineoplastic Therapy Research: Bullfrog (Rana catesbeiana Shaw) Oil Nanostructured Systems.

    Science.gov (United States)

    Amaral-Machado, Lucas; Xavier-Júnior, Francisco H; Rutckeviski, Renata; Morais, Andreza R V; Alencar, Éverton N; Dantas, Teresa R F; Cruz, Ana K M; Genre, Julieta; da Silva-Junior, Arnóbio A; Pedrosa, Matheus F F; Rocha, Hugo A O; Egito, Eryvaldo S T

    2016-01-01

    Bullfrog oil is a natural product extracted from the Rana catesbeiana Shaw adipose tissue and used in folk medicine for the treatment of several diseases. The aim of this study was to evaluate the extraction process of bullfrog oil, to develop a suitable topical nanoemulsion and to evaluate its efficacy against melanoma cells. The oil samples were obtained by hot and organic solvent extraction processes and were characterized by titration techniques and gas chromatography mass spectrometry (GC-MS). The required hydrophile-lipophile balance and the pseudo-ternary phase diagram (PTPD) were assessed to determine the emulsification ability of the bullfrog oil. The anti-tumoral activity of the samples was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for normal fibroblast (3T3) and melanoma (B16F10) cell lines. Both extraction methods produced yielded around 60% and the oil was mainly composed of unsaturated compounds (around 60%). The bullfrog oil nanoemulsion obtained from PTPD presented a droplet size of about 390 nm and polydispersity = 0.05 and a zeta potential of about -25 mV. Both the bullfrog oil itself and its topical nanoemulsion did not show cytotoxicity in 3T3 linage. However, these systems showed growth inhibition in B16F10 cells. Finally, the bullfrog oil presented itself as a candidate for the development of pharmaceutical products free from cytotoxicity and effective for antineoplastic therapy. PMID:27144557

  4. Diet of introduced bullfrogs (Rana catesbeiana): Predation on and diet overlap with native frogs on Daishan Island, China

    Science.gov (United States)

    Wu, Zhengjun; Li, Y.; Wang, Y.; Adams, Michael J.

    2005-01-01

    We examined diet of introduced Bullfrogs (Rana catesbeiana) and three native frog species (Rana limnocharis, Rana nigromaculata, and Bufo bufo gargarizans) co-occurring at a group of ponds on Daishan Island, east of China, to gain insight into the nature of potential interactions between Bullfrogs and native frog species. For postmetamorphic Bullfrogs, aquatic prey items dominated volumetrically. Prey size, diet volume and volumetric percentage of native frogs in diet increased with Bullfrog body size. The number and volumetric percentage of native frogs in the diet were not different for female and male Bullfrogs, and both were higher for adults than for juveniles. Diet overlap between males and juveniles was higher than that between males and females and between females and juveniles. Diet overlap with each native frog species of male Bullfrogs was lower than that of female Bullfrogs and juvenile Bullfrogs. We did not exam effects of Bullfrogs on native frogs but our results suggest that the primary threat posed by juvenile Bullfrogs to native frogs on Daishan Island is competition for food, whereas the primary threat posed by male Bullfrogs is direct predation. Female Bullfrogs may threaten native frogs by both competition and predation. These differences among Bullfrog groups may be attributed to differences in body size and microhabitat use.

  5. Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila

    Science.gov (United States)

    Zhang, Junjie; Zou, Wenzheng; Yan, Qingpi

    2008-08-01

    Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups. Each bullfrog in bacterium-injected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml, while each one in control group injected i.p. with 0.2 ml sterile saline solution (0.85%, w/v). Three bullfrogs in both groups were sampled at 0, 1, 3, 7, 11, 15 and 20 days post-injection (dpi) for the evaluation of non-specific immune parameters. It was observed that intraperitoneal injection of A. hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood. Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group. However, a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes. No significant difference in changes in the number of peripheral erythrocytes, serum superoxide dismutase (SOD) activity, and lysozyme activity was detected between the two groups. It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A. hydrophila infection.

  6. Non-specific immune response of bullfrog Rana catesbeiana to intraperitoneal injection of bacterium Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Non-specific immune response of bullfrog Rana catesbeiana to pathogenic Aeromonas hydrophila was studied to 60 individuals in two groups. Each bullfrog in bacterium-injected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension at a density of 5.2 × 106 CFU/ml, while each one in control group injected i.p. with 0.2 ml sterile saline solution (0.85%, w/v). Three bullfrogs in both groups were sampled at 0, 1, 3, 7, 11, 15 and 20 days post-injection (dpi) for the evaluation of non-specific immune parameters. It was observed that intraperitoneal injection of A. hydrophila significantly increased the number of leucocytes and that of NBT-positive cells in peripheral blood. Significant increases in serum bactericidal activity and serum acid phosphatase activity were also observed in the bacterium-injected frogs when compared with those in the control group. However, a significant reduction was detected in vitro in phagocytosis activity of peripheral blood phagocytes. No significant difference in changes in the number of peripheral erythrocytes, serum superoxide dismutase (SOD) activity, and lysozyme activity was detected between the two groups. It is suggested that bullfrogs may produce a series of non-specific immune reactions in response to the A. hydrophila infection.

  7. Malnutrition in farm-cultured bullfrog (Rana catesbeiana fed on bovine milled lung in Argentina

    Directory of Open Access Journals (Sweden)

    J A Coppo, N B Mussart

    2005-11-01

    Full Text Available The true nutritional requirements of bullfrog (Rana catesbeiana, Anura: Ranidae are still controversial. In Argentine hatcheries, bullfrogs are fed on commercial balanced diets elaborated for fish; high price of balanced food decreases the relationship cost / benefit. This study had the objective to verify the nutritious effectiveness of bovine lung, by means of liveweight gains and metabolic and nutritional biochemical indicators controls. Eighty frogs were randomly divided into experimental (E and control (C groups of 40 animals each. Controls consumed a fish commercial balanced diet (23% protein in dry matter, DM, while those in group E were fed on bovine milled lung (16% protein, DM. Food was administered at a rate of 5% of liveweight/day (DM for both groups. The weighings and collection of samples were made on days 0 and 120. One frog of group C and 8 frogs of group E died during the study. Control animals did not register physical abnormalities. On the other hand, emaciation, adynamia, weakness, anorexy, and skin abnormal coloration were verified in some amphibians of group E. At the end of the study, liveweight and albumin, creatinine, urea, cholesterol, triglycerides, glucose, phosphorous and magnesium serum values, were significantly lower in group E than in group C (p < 0.05. This changes are attributed to metabolic imbalances related to malnutrition and reveal that bovine lung is not an appropriate food for captive bullfrog.

  8. Occurrence of heavy metals and antibiotic resistance in bacteria from internal organs of american bullfrog (Rana catesbeiana) raised in Malaysia

    OpenAIRE

    Lee SW; M. Najiah; W Wendy; M Nadirah; SH Faizah

    2009-01-01

    A total of 40 bacteria have been successfully isolated from internal organs of the American bullfrog (Rana catesbeiana) raised in Malaysia, namely, eight isolates of Aeromonas spp., 21 of Edwardsiella spp., six of Flavobacterium spp. and five of Vibrio spp. In terms of antibiotic susceptibility testing, each isolate was tested against 21 antibiotics, resulting in 482 (57.3%) cases of sensitivity and 61 (7.3%) cases of partial sensitivity. Meanwhile, 297 (35.4%) bacterial isolates were registe...

  9. Cathelicidins from the bullfrog Rana catesbeiana provides novel template for peptide antibiotic design.

    Directory of Open Access Journals (Sweden)

    Guiying Ling

    Full Text Available Cathelicidins, a class of gene-encoded effector molecules of vertebrate innate immunity, provide a first line of defense against microbial invasions. Although cathelicidins from mammals, birds, reptiles and fishes have been extensively studied, little is known about cathelicidins from amphibians. Here we report the identification and characterization of two cathelicidins (cathelicidin-RC1 and cathelicidin-RC2 from the bullfrog Rana catesbeiana. The cDNA sequences (677 and 700 bp, respectively encoding the two peptides were successfully cloned from the constructed lung cDNA library of R. catesbeiana. And the deduced mature peptides are composed of 28 and 33 residues, respectively. Structural analysis indicated that cathelicidin-RC1 mainly assumes an amphipathic alpha-helical conformation, while cathelicidin-RC2 could not form stable amphipathic structure. Antimicrobial and bacterial killing kinetic analysis indicated that the synthetic cathelicidin-RC1 possesses potent, broad-spectrum and rapid antimicrobial potency, while cathelicidin-RC2 exhibited very weak antimicrobial activity. Besides, the antimicrobial activity of cathelicidin-RC1 is salt-independent and highly stable. Scanning electron microscopy (SEM analysis indicated that cathelicidin-RC1 kills microorganisms through the disruption of microbial membrane. Moreover, cathelicidin-RC1 exhibited low cytotoxic activity against mammalian normal or tumor cell lines, and low hemolytic activity against human erythrocytes. The potent, broad-spectrum and rapid antimicrobial activity combined with the salt-independence, high stability, low cytotoxic and hemolytic activities make cathelicidin-RC1 an ideal template for the development of novel peptide antibiotics.

  10. Stomach contents from invasive American bullfrogs Rana catesbeiana (= Lithobates catesbeianus on southern Vancouver Island, British Columbia, Canada

    Directory of Open Access Journals (Sweden)

    Kevin Jancowski

    2013-03-01

    Full Text Available Invasive alien American bullfrog populations are commonly identified as a pernicious influence on the survival of native species due to their adaptability, proliferation and consequent ecological impacts through competition and predation. However, it has been difficult to determine conclusively their destructive influence due to the fragmentary and geographically dispersed nature of the historical database. An expanding meta-population of invasive American bullfrogs, Rana catesbeiana (= Lithobates catesbeianus, became established on southern Vancouver Island, British Columbia, Canada in the mid- to late 1980s. An on-going bullfrog control program begun in 2006 offered a unique opportunity to examine the stomach contents removed from 5,075 adult and juvenile bullfrogs collected from 60 sites throughout the active season (April to October. Of 15 classes of organisms identified in the diet, insects were numerically dominant, particularly social wasps and odonates (damselflies and dragonflies. Seasonality and site-specific habitat characteristics influenced prey occurrence and abundance. Native vertebrates in the diet included fish, frogs, salamanders, snakes, lizards, turtles, birds, and mammals, including some of conservation concern. Certain predators of bullfrog tadpoles and juveniles are commonly preyed upon by adult bullfrogs, thereby suppressing their effectiveness as biological checks to bullfrog population growth. Prey species with anti-predator defences, such as wasps and sticklebacks, were sometimes eaten in abundance. Many prey species have some type of anti-predator defence, such as wasp stingers or stickleback spines, but there was no indication of conditioned avoidance to any of these. Results from this study reinforce the conclusion that, as an invasive alien, the American bullfrog is an opportunistic and seemingly unspecialized predator that has a uniquely large and complex ecological footprint both above and below the water surface.

  11. Occurrence of heavy metals and antibiotic resistance in bacteria from internal organs of american bullfrog (Rana catesbeiana raised in Malaysia

    Directory of Open Access Journals (Sweden)

    SW Lee

    2009-01-01

    Full Text Available A total of 40 bacteria have been successfully isolated from internal organs of the American bullfrog (Rana catesbeiana raised in Malaysia, namely, eight isolates of Aeromonas spp., 21 of Edwardsiella spp., six of Flavobacterium spp. and five of Vibrio spp. In terms of antibiotic susceptibility testing, each isolate was tested against 21 antibiotics, resulting in 482 (57.3% cases of sensitivity and 61 (7.3% cases of partial sensitivity. Meanwhile, 297 (35.4% bacterial isolates were registered as resistant. The multiple antibiotic resistance (MAR index of each bacterial species indicated that bacteria from raised bullfrogs have been exposed to tested antibiotics with results ranging from 0.27 to 0.39. Additionally, high percentages of heavy metal resistance among these isolates were observed, with values ranging from 85.0 to 100.0%. The current results provided us information on bacterial levels of locally farmed bullfrogs exposed to copper, cadmium, chromium as well as 21 types of antibiotics.

  12. Antibiotic Resistance and Heavy Metals Tolerance in Gram-Negative Bacteria from Diseased American Bullfrog (Rana catesbeiana) Cultured in Malaysia

    Institute of Scientific and Technical Information of China (English)

    M Na-jian; S W Lee; W Wendy; L W Tee; M Nadirah; S H Faizah

    2009-01-01

    A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog (Rana catesbeiana) cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. (46 isolates) followed by Aeromonas spp. (33 isolates), Flavobacterium spp. (31 isolates), and Vibrio spp. (30 isolates). Majority of the bacterial isolates were found sensitive to furazolidone (85.0%), chloramphenicol (85.0%), oxolinic acid (90.0%), florfenicol (95.0%), and flumequine (97.5%). On the other hand, most of the bacterial isolates were resistant to oleandomycin (77.5%) and lincomycin (87.5%). Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance (MAR) index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.

  13. Free radical scavenging activity of a novel antioxidative peptide purified from hydrolysate of bullfrog skin, Rana catesbeiana Shaw.

    Science.gov (United States)

    Qian, Zhong-Ji; Jung, Won-Kyo; Kim, Se-Kwon

    2008-04-01

    In the present study, a peptide having antioxidant properties was isolated from bullfrog skin protein, Rana catesbeiana Shaw. Bullfrog skin protein was hydrolyzed using alcalase, neutrase, pepsin, papain, alpha-chymotrypsin and trypsin. Antioxidant activities of respective hydrolysates were evaluated using lipid peroxidation inhibition assay and direct free radical scavenging activity by using electron spin resonance (ESR) spectrometer. Among hydrolysates, alcalase derived hydrolysate exhibited the highest antioxidant activities than those of other enzyme hydrolysates. In order to purity a peptide having potent antioxidant properties, alcalase hydrolysate was separated using consecutive chromatographic methods on a Hiprep 16/10 DEAE FF anion exchange column, Superdex Peptide 10/300 GL gel filtration column and highan octadecylsilane (ODS) C18 reversed phase column. Finally, a potent antioxidative peptide was isolated and its sequence was identified to be LEELEEELEGCE (1487 Da) by Q-TOF ESI mass spectroscopy. This antioxidant peptide from bullfrog skin protein (APBSP) inhibited lipid peroxidation higher than that of alpha-tocopherol as positive control and efficiently quenched different sources of free radicals: DPPH radical (IC(50)=16.1 microM), hydroxyl radical (IC(50)=12.8 microM), superoxide radical (IC(50)=34.0 microM) and peroxyl radical (IC(50)=32.6 microM). Moreover, MTT assay showed that this peptide does not exert any cytotoxicity on human embryonic lung fibroblasts cell line (MRC-5). PMID:17512726

  14. Efeito da temperatura sobre o desempenho da rã-touro (Rana catesbeiana Shaw, 1802 Temperature effect on performance of bull-frog (Rana catesbeiana Shaw, 1802

    Directory of Open Access Journals (Sweden)

    Mario Roberto Chim Figueiredo

    1999-08-01

    Full Text Available Este estudo foi realizado para avaliar os efeitos do ambiente sobre a performance de rã-touro (Rana catesbeiana Shaw, 1802, criada em gaiolas de fibra de vidro instaladas no interior de estufas climatizadas. Após um período inicial de 15 dias de adaptação às instalações, à temperatura constante de 25,0ºC, os seguintes tratamentos foram aplicados: temperaturas de 23,0; 26,0; 29,0; 32,0; e 35,0ºC, por 30 dias, para rãs com 100 g PV inicial; 24,5; 26,0; 27,5; 29,0; 30,5; e 32,0ºC, também por 30 dias, para rãs com 20 g PV inicial; e a combinação das temperaturas de 26,0 e 29,0ºC com os fotoperíodos de 8, 12 e 16 h de luz a cada 24 horas, para rãs com 100 g PV inicial. Derivando-se as equações de regressão que explicam os efeitos de temperatura sobre o desempenho das rãs, estimaram-se melhores ganhos de peso à temperatura de 27,6e30,1ºC, para rãs com 100 e 20 g PV inicial, respectivamente, com melhor crescimento a 28,2ºC, para as rãs de 100 g PV inicial, e a 29,7ºC, para as rãs de 20 g PV inicial. A temperatura interagiu com fotoperíodo nos seus efeitos sobre ganho de peso e crescimento corporal, peso e rendimento de carcaça, consumo de alimentos e conversão alimentar.This study was carried out to evaluate the environmental effects on bull-frog (Rana catesbeiana Shaw, 1802 performance, raised in fiber glass cages installed inside acclimatized incubators. After an initial period of 15 days of adaptation, at constant temperature of 25.0ºC, the following experimental treatments were applied: temperatures of 23.0, 26.0, 29.0, 32.0 and 35.0ºC per 30 days for frogs with 100 g initial LW; 24.5, 26.0, 27.5, 29.0, 30.5, and 32.0ºC, also on 30 days, for frogs with 20 g initial LW; and the combination of the temperatures of 26.0 and 29.0ºC with the photo periods of 8, 12 and 16 h of light at every 24 hours, for frogs with 100 g initial weight. By deriving the regression equations that explain the temperature effects on the

  15. Diet composition of post-metamorphic bullfrogs (Rana catesbeiana) in the Zhoushan archipelago,Zhejiang Province, China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Bullfrogs (Runa catesbeiana) are listed as one of the 100 worst invasive alien species in the world.They are generalist predators and thus may affect native species through predation.In previous studies,the food contents of bullfrogs were mostly examined at a single site.In the present study,the diet composition of post-metamorphic bullfrogs on eight islands (Daishan,Liuheng,Xiushan,Fodu,Taohua,Xiashi,Cezi,and Putuoshan) in the Zhoushan Archipelago,Zhejiang Province of China,were examined by using the stomach flushing method from June 30 to August 11 in 2005.A total 0f391 individual frogs were measured,including 113 adults and 278 juveniles.The analysis of the stomach contents shows that,for adult bullfrogs,the most important prey (by diet volume) overall were Decapoda,Coleoptera,Odonata,Mesogastropoda,Raniformes,and Cypriniformes.For juvenile bullfrogs,these were Decapoda,Coleoptera,Cypriniformes,Odonata,Orthoptera,Hymenoptera,Lepidoptera larvae,Mesogastropoda,and Raniformes.Moreover,the prey size and diet volume increased with the body size of both adult and juvenile bullfrogs.The diet composition of primary preys of bullfrogs was significantly different among the islands.The results indicate that bullfrogs exert different predatory influences on native fauna at different sites and that bullfrogs are generalist predators with extensive ecological impacts on native fauna.

  16. Bullfrog tadpole (Rana catesbeiana) and red swamp crayfish (Procambarus clarkii) predation on early life stages of endangered razorback sucker (Xyrauchen texanus)

    Science.gov (United States)

    Mueller, G.A.; Carpenter, J.; Thornbrugh, D.

    2006-01-01

    Bullfrog tadpoles (Rana catesbeiana) and red swamp crayfish (Procambarus clarkii) are widespread introduced taxa that are problematic throughout the western United States. Their impact on native amphibians and crustaceans is well documented, but less is known regarding their influence on native fishes. Predator-prey tank tests showed both species consumed eggs and larvae of the endangered razorback sucker (Xyrauchen texanus) in a laboratory setting. Tadpoles consumed 2.2 razorback sucker eggs/d and 1.4 razorback sucker larvae/d, while crayfish ate 6.0 eggs/d and 3.5 larvae/d. Relatively high densities of bullfrog tadpoles and crayfish in razorback sucker spawning areas suggest that these nonnative taxa might pose a threat to the recruitment success of this and other imperiled native fish.

  17. Call recognition in the bullfrog, Rana catesbeiana: Generalization along the duration continuuma)

    OpenAIRE

    Simmons, Andrea Megela

    2004-01-01

    Male bullfrogs emit multicroak, quasiharmonic advertisement calls that function in mate attraction and neighbor recognition. The degree of variability of acoustic features in these calls can influence perceptual decisions by conspecific receivers. Analysis of duration of individual croaks in spontaneous advertisement calls of a sample of males shows considerable intraindividual variability in this feature, even within short chorusing bouts. The influence of this intraindividual variability on...

  18. Ovine thyroid stimulating hormone (TSH) heterologously stimulates production of thyroid hormones from Chinese soft-shell turtle (Pelodiscus sinensis) and bullfrog (Rana catesbeiana and Rana rugulosa) thyroids in vitro.

    Science.gov (United States)

    Huang, Wei-Tung; Chien, Jung-Tsun; Weng, Ching-Feng; Jeng, Yung-Yue; Lu, Li-Chia; Yu, John Yuh-Lin

    2009-06-01

    Thyroid hormones are important for regulating a variety of developmental processes in vertebrates, including growth, differentiation, metamorphosis, and oxidative metabolism. In particular, this study focused on the in vitro production of thyroxine (T(4)) and triiodothyronine (T(3)) from thyroids in American bullfrogs (Rana catesbeiana), Chinese bullfrogs (Rana rugulosa Wiegmann), and Chinese soft-shell turtles (Pelodiscus sinensis) treated with ovine thyroid stimulating hormone (TSH) at different culture intervals (2, 4, 8, and 12 h) and dosages (1, 10, 50 or 100 ng). The levels of T(4) and T(3) in the tested animals were elevated upon stimulation in a time- and dose-dependent manner, indicating de novo synthesis of T(4) and T(3). Significantly higher hormone levels were observed in the Chinese bullfrog compared to the other two species, for both the time-course and dose-response experiments. Although the bullfrog secreted significantly higher levels of T(4) and T(3), a higher T(4)-conversion capacity was found in the Chinese soft-shell turtle. The highest ratios of T(3) to T(4) were observed in the American bullfrog and Chinese soft-shell turtle for the time-course and dose-response experiments, respectively. These findings suggest that the Chinese soft-shell turtle and bullfrog thyroids can accept ovine TSH for T(4)- and T(3)-formation in a time- and dose-dependent manner, supporting the hypothesis that the binding interactions between TSHs and thyroidal receptors are conserved in vertebrates. PMID:19535032

  19. Identification of Elizabethkingia meningoseptica from American bullfrog (Rana catesbeiana farmed in Sabah, Malaysia using PCR method and future management of outbreak

    Directory of Open Access Journals (Sweden)

    Zainuri, N.

    2013-01-01

    Full Text Available Aims: High demand for frog meat in Malaysia especially the American bullfrog (Rana catesbeiana has promoted intensive farming of the animal. However, the farming of American bullfrog is restricted by the occurrence of diseases. This study reports the first isolation of Elizabethkingia meningoseptica from specimens of American bullfrog that suffer from cataract and ‘red-leg’ syndrome.Methodology and Result: The pathogen was isolated from eyes and internal organs (liver, kidney and spleen of thediseased bullfrog specimens. All the bacterial isolates were subjected to phenotypic characterization and antibiotic susceptibility assay, and further identified by using the 16S rDNA sequencing analysis. We designed two pair of specific PCR primers (22-25 mers which are complimentary to the β-lactamase gene in the reference strain ofE. meningoseptica ATCC49470. The result showed all the bacterial isolates shared similar phenotypic characters and antibiotic susceptibility. BLAST analysis of the 16S rDNA sequences indicated that the bacterial isolates had very high sequence homology (100% with E. meningospetica ATCC49470 and E. meningoseptica isolates from mosquito. The two PCR primers were very specific to E. meningoseptica isolates of this study. Conclusion, significance and impact of study: This is the first isolation and characterization of bacterial pathogen, E. meningoseptica in cultured American bullfrog (Rana catesbeina that suffered from eye cataract and ‘red-leg’syndrome in Sabah, Malaysia. It is suspected that one of the possible transmission routes of the bacterial pathogen could be via mosquito bites. The findings suggest that there is urgent requirement for standard guideline of good farming practice to be adopted in frog farms throughout the country. Such a guideline can help in minimizing economic losses, preventing transmission of the zoonotic bacterial pathogen to farm workers, and sustaining the industry in Malaysia andupgrading

  20. Suplementação alimentar com vitamina C e desempenho zootécnico de girinos de rã-touro (Rana catesbeiana = Alimentary supplementation of Vitamin C and the performance indexes of bullfrog tadpoles (Rana catesbeiana

    Directory of Open Access Journals (Sweden)

    Neidison Carneiro Colombano

    2007-07-01

    Full Text Available Neste trabalho avaliou-se o desempenho zootécnico de girinos de rã-touro (Rana catesbeiana cuja dieta foi suplementada com vitamina C. Girinos com peso médio inicial de 12,3 mg ± 2 mg foram distribuídos em 16 caixas de água de 40 L, na densidade deum girino L-1. Os animais foram alimentados com dieta suplementada com zero (controle, 1.000, 1.500 e 2.000 mg de vitamina C kg-1 de ração, durante 75 dias. Após esse período foram avaliados quanto à sobrevivência, porcentagem de metamorfose, ganho de peso e taxade crescimento específico. As maiores taxas de sobrevivência (93%, porcentagem de metamorfose (29%, ganho de peso (4,22 g e taxa de crescimento específico (6,03% dia-1 foram dos animais que receberam 2.000 mg de vitamina C kg-1. O grupo não-suplementado foi o que apresentou o pior desempenho. Os resultados sugerem que a adição de 2.000 mg de vitamina C kg-1 produz efeitos benéficos para o ganho de peso, crescimento específico, metamorfose e sobrevivência de girinos de rã-touro.The present study had as objective to evaluate the effects of vitamin C supplementation on the performance indices of bullfrog (Rana catesbeiana tadpoles. The tadpoles, with an average weight of 12.3 ± 2 mg, were distributed in 16 boxes (40 L, with 1 tadpole L-1. They received diets supplemented with zero (control, 1,000, 1,500 and 2,000 mg of vitamin C kg-1 of diet, during 75 days. After this period, the survival, metamorphosis percentage, weight gain and specific growth rate were evaluated. The tadpoles that received 2,000 mg vitamin C kg-1 ration showed the best results in survival (93%, the best percentage of metamorphosis (29%, the greatest weight gain (4.22 g and the best specific growth rate (6.03% day-1. The worst performance was observed in the tadpoles that did not receive vitamin C. The results suggest that ration with 2,000 mg of vitamin C kg-1 improves weight gain, specific growth rate, metamorphosis andsurvival of the bullfrog tadpoles.

  1. Call recognition in the bullfrog, Rana catesbeiana: Generalization along the duration continuum

    Science.gov (United States)

    Simmons, Andrea Megela

    2004-03-01

    Male bullfrogs emit multicroak, quasiharmonic advertisement calls that function in mate attraction and neighbor recognition. The degree of variability of acoustic features in these calls can influence perceptual decisions by conspecific receivers. Analysis of duration of individual croaks in spontaneous advertisement calls of a sample of males shows considerable intraindividual variability in this feature, even within short chorusing bouts. The influence of this intraindividual variability on behavior was examined in a series of evoked calling experiments. When presented with synthetic calls whose croak durations varied over the range of the natural variability in this feature, males responded similarly to intermediate and long duration croaks, but significantly less to short duration croaks. When presented with playbacks of calls with croak durations outside the natural range of variability, males again responded significantly less to shorter durations. The response gradient for duration is thus asymmetrical, with stimuli at the shorter end of the continuum evoking fewer responses than stimuli at the longer end. This asymmetry may be related to the biological demands of rejecting perception of heterospecific advertisement calls, and of mediating appropriate responses to conspecific aggressive calls. The shape of the response gradient for duration may reflect a process of stimulus generalization.

  2. Exposure to lead induces hypoxia-like responses in bullfrog larvae (Rana catesbeiana)

    Energy Technology Data Exchange (ETDEWEB)

    Rice, T.M.; Blackstone, B.J.; Nixdorf, W.L.; Taylor, D.H.

    1999-10-01

    Amphibians collected around mining sites, areas with extensive automobile traffic, and shooting ranges have been documented to contain high levels of lead. Lead-exposed amphibians might respond as if in hypoxic conditions because exposure is known to decrease hemoglobin levels, damage erythrocytes, and alter respiratory surfaces. Therefore, the authors exposed bullfrog larvae to either 0 or 780 {micro}g/L Pb and either 3.50 or 7.85 mg/L oxygen for 7 d and monitored activity, trips to the surface, and buccal ventilation rates. Activity was significantly decreased in larvae exposed to low oxygen, Pb, or both compared to activity of larvae in high oxygen with no Pb. Larvae exposed to both Pb and low oxygen displayed higher buccal ventilation rates than larvae exposed to either treatment separately. Lead-exposed larvae surfaced significantly more often than unexposed larvae even under high-oxygen conditions. Lead-exposed larvae decreased in mass during the exposure period, whereas unexposed larvae increased in mass. Lead exposure could decrease survival of larvae in the field not only because of physiological problems due to decreased oxygen uptake but also because of greater predation pressure due to increased presence at the surface and reduced growth rates.

  3. Incidence and impact of axial malformations in larval bullfrogs (Rana catesbeiana) developing in sites polluted by a coal-burning power plant

    International Nuclear Information System (INIS)

    Amphibian malformations have recently received much attention from the scientific community, but few studies have provided evidence linking environmental pollution to larval amphibian malformations in the field. The authors document an increased incidence of axial malformations in bullfrog larvae (Rana catesbeiana) inhabiting two sites contaminated with coal combustion wastes. In the polluted sites, 18 and 37% of larvae exhibited lateral curvatures of the spine, whereas zero and 4% of larvae from two reference sites had similar malformations. Larvae from the most heavily polluted site had significantly higher tissue concentrations of potentially toxic trace elements, including As, Cd, Se, Cu, Cr, and V, compared with conspecifics from the reference sites. In addition, malformed larvae from the cost contaminated site had decreased swimming speeds compared with those of normal larvae from the same site. The authors hypothesize that the complex mixture of contaminants produced by coal combustion is responsible for the high incidence of malformations and associated effects on swimming performance

  4. Molecular cloning and expression of prohormone convertases PC1 and PC2 in the pituitary gland of the bullfrog, Rana catesbeiana.

    Science.gov (United States)

    Yaoi, Yuichi; Suzuki, Masakazu; Tomura, Hideaki; Kikuyama, Sakae; Tanaka, Shigeyasu

    2003-09-01

    We cloned cDNAs encoding PC1 and PC2 from a cDNA library constructed for the anterior pituitary gland of the bullfrog (Rana catesbeiana) and sequenced them. The bullfrog PC1 cDNA consisted of 2972 base pairs (bp) with an open reading frame of 2208 bp and encoded a protein of 736 amino acids, including a putative signal peptide of 26 amino acids. The protein showed a high homology to R. ridibunda PC1 (95.1%) and mammalian PC1 (72.6%). The bullfrog PC2 cDNA consisted of 2242 bp with an open reading frame of 1914 bp and encoded a protein of 638 amino acids, including a putative signal peptide of 23 amino acids. This protein showed a high homology to R. ridibunda PC2 (95.5%) and mammalian PC2 (84.8%). The catalytic triad of serine proteinases of the subtilisin family was found at Asp-168, His-209, and Ser-383 in the PC1 protein and at Asp-167, His-208, and Ser-384 in the PC2 protein. In situ hybridization staining revealed that PC2 mRNA was detected in corticotrope cells of the tadpoles, but not in those of the adults. In the adult, only PC1 mRNA was detected in the pars distalis but both PC1 and PC2 mRNAs were detected in the pars intermedia. The data also showed that PC1 mRNA was expressed in gonadotrope cells. PMID:14578575

  5. Distribution and Origin of VIP-, SP-, and Phospholipase Cβ2 -Immunoreactive Nerves in the Tongue of the Bullfrog, Rana catesbeiana.

    Science.gov (United States)

    Tadokoro, Osamu; Ando, Hiroshi; Kawahara, Ichiro; Asanuma, Naokazu; Okumura, Masayo; Kitagawa, Junichi; Kondo, Eiji; Yagasaki, Hiroshi

    2016-07-01

    Previous studies have found a few intralingual ganglionic cells that were immunoreactive to vasoactive intestinal polypeptide (VIP) in the frog. A recent study reported a large number of such cells, and the possibility of the release of substance P (SP) from these. The aim of the present study was to investigate the distribution, origin, and colocalization of VIP- and SP- immunoreactive nerves in the tongue of the bullfrog, R. catesbeiana. In addition, the study also examined the colocalization of SP and phospholipase Cβ2 (PLCβ2 ) in the tongue and jugular ganglion. VIP immunoreactivity was seen in unipolar cells that were sparse in nerve bundles in the submucosal and muscle layers. The density of VIP-immunoreactive cells was approximately 4.8 cells/mm(3) . Their fibers terminated in the vicinity of the epithelial basal layer of the fungiform papillae. SP immunoreactivity was not seen in the VIP-immunoreactive cells, but was observed in pseudounipolar cells in the jugular ganglion. The SP fibers terminated close to the free surface, showing spindle- and button-like profiles. Transection of glossopharyngeal nerve resulted in the persistence of VIP-immunoreactive cells and the disappearance of SP-immunoreactive fibers in the tongue. SP immunoreactivity was co-expressed with PLCβ2 in both the tongue and jugular ganglia. No PLCβ2 immunoreactivity was seen in cells comprising the epithelial taste disk. These findings indicate that the origin of VIP nerve fibers are unipolar cells in the tongue, and SP and PLCβ2 fibers originate from pseudounipolar cells that may be able to release SP primarily in the jugular ganglion. Anat Rec, 299:929-942, 2016. © 2016 Wiley Periodicals, Inc. PMID:26916909

  6. Effect of bullfrog (Rana catesbeiana oil administered by gavage on the fatty acid composition and oxidative stress of mouse liver

    Directory of Open Access Journals (Sweden)

    L.P. Silva

    2004-10-01

    Full Text Available The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil, corresponding to 0.4% of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity in mouse liver. The activities of aspartate aminotransferase (AST, alkaline phosphatase (ALP, alanine aminotransferase (ALT, and gamma-glutamyltransferase (GGT, biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60% in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05 compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25% was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS was increased from 2.3 ± 0.2 to 12.3 ± 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 ± 32 to 1110 ± 45 µmol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 ± 0.12 to 342.84 ± 0.13 and 9.38 ± 0.60 to 20.06 ± 0.27 U/g, respectively and in serum (from 95.41 ± 6.13 to 120.32 ± 3.15 and 234.75 ± 11.5 to 254.41 ± 2.73 U/l, respectively, suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 ± 0.29 to 315.98 ± 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver.

  7. Comportamento alimentar e qualidade da água em tanques de criação de girinos de rã-touro Rana catesbeiana - DOI: 10.4025/actascianimsci.v30i1.3619 Feeding behavior and water quality in tanks conataining bullfrog tadpoles Rana catesbeiana - DOI: 10.4025/actascianimsci.v30i1.3619

    Directory of Open Access Journals (Sweden)

    Joceli Cristina Leite de Morais

    2008-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o comportamento alimentar e a qualidade da água em tanques de criação de girinos de rã-touro Rana catesbeiana durante 56 dias, a partir do estágio 25 da Tabela de Gosner (1960, criados em tanques de alvenaria com capacidade de 1000 L. Os girinos que receberam ração (R e alga + plâncton + ração (APR apresentaram o melhor peso e sobrevivência, diferindo significativamente (p s = 0,39; p The objective of this study was to evaluate the effect of food treatments and water quality on the development of bullfrog tadpoles. The analysis, carried out in 1000 L tanks, was undertaken by weight and survival rates, during 56 days, as from stage 25 (Gosner, 1960. Treatments with ration (R and algae + plankton + ration (APR had the best results in weight and survival rates, which were significantly different (p s = 0.39; p < 0.05. From the 14th day of age, bullfrog tadpoles changed their feeding behavior, or rather, a search for food items other than plankton occurred. The utilization of combined natural and artificial (ration diets to feed bullfrog tadpoles was feasible and yielded a satisfactory development in the animals.

  8. Avaliação de métodos de coleta de fezes para determinação da digestibilidade protéica em rã-touro (Rana catesbeiana Evaluation methods of feces collection for determination of protein digestibility in bullfrog (Rana catesbeiana

    Directory of Open Access Journals (Sweden)

    José Luiz Pedreira Mouriño

    2006-06-01

    Full Text Available O presente trabalho teve como objetivo avaliar diferentes metodologias de coleta de fezes para determinação da digestibilidade protéica de alimentos para a rã-touro (Rana catesbeiana. As metodologias estudadas foram o método de coleta total das fezes; o método de coleta parcial das fezes usando indicador; o método de dissecação intestinal e o método por decantação de fezes com indicador, utilizando aquários para ensaios de nutrição com peixes. Os resultados dos CDA PB da ração obtidos para avaliação dos métodos de coleta foram: 62,1%, 65,0%, 61,3% e 70,3%, respectivamente. Todos os métodos de coleta de fezes são adequados para a realização de ensaios de digestibilidade com rãs.The present work had as objective to evaluate different methodologies of feces collection in the determination of the protein digestibility of food feeds for the bullfrog (Rana catesbeiana. The studied methodologies were: total collection of excrements, partial collection of excrements using indicator, intestinal dissection, and excrement decantation with pointer using aquariums for assays of nutrition with fish. The results for CDA PB obtained in this assay were: 62.1%, 65.0%, 61.3% and 70.3% respectively. All the methods of excrement collection can be executed for determination of protein digestibility in bullfrog.

  9. Emerging Pathogen in Wild Amphibians and Frogs (Rana catesbeiana) Farmed for International Trade

    OpenAIRE

    Mazzoni, Rolando; Cunningham, Andrew A.; Daszak, Peter; Apolo, Ada; Perdomo, Eugenio; Speranza, Gustavo

    2003-01-01

    Chytridiomycosis is an emerging disease responsible for global decline and extinction of amphibians. We report the causative agent, Batrachochytrium dendrobatidis, in North American bullfrogs (Rana catesbeiana) farmed for the international restaurant trade. Our findings suggest that international trade may play a key role in the global dissemination of this and other emerging infectious diseases in wildlife.

  10. Mass mortality associated with a frog virus 3-like Ranavirus infection in farmed tadpoles Rana catesbeiana from Brazil

    OpenAIRE

    Mazzoni, Rolando; de Mesquita, Albenones José; Fleury, Luiz Fernando F.; de Brito, Wilia Marta Elsner Diederichsen; Nunes, Iolanda A.; Robert, Jacques; Morales, Heidi; Coelho, Alexandre Siqueira Guedes; Barthasson, Denise Leão; Galli, Leonardo; Catroxo, Marcia H. B.

    2009-01-01

    Ranviruses (Iridoviridae) are increasingly associated with mortality events in amphibians, fish, and reptiles. They have been recently associated with mass mortality events in Brazilian farmed tadpoles of the American bullfrog Rana catesbeiana Shaw. 1802. The objectives of the present study were to further characterize the virus isolated from sick R. catesbeiana tadpoles and confirm the etiology in these outbreaks. Sick tadpoles were collected in 3 farms located in Goiás State, Brazil, from 2...

  11. USING INTERNAL RADIO TRANSMITTERS TO DETERMINE THE BEHAVIORAL RESPONSE OF BULLFROGS, RANA CATESBEIANA, TO SEASONAL POND DRYING IN THE WILLAMETTE VALLEY, OREGON

    Science.gov (United States)

    We implanted radio tags in adult bullfrogs from three ponds located in a Willamette Valley game reserve to determine their behavior and habitat use as the ponds dried during late summer. We used radio telemetry and a Global Position System (GPS) to locate and record the position ...

  12. Immunocytochemical localization of secretory phospholipase A(2)-like protein in the pituitary gland and surrounding tissue of the bullfrog, Rana catesbeiana.

    Science.gov (United States)

    Yaoi, Y; Kikuyama, S; Hayashi, H; Hanaoka, Y; Sakai, M; Tanaka, S

    2001-05-01

    Previously, we obtained a protein that has considerable amino acid sequence homology with secretory phospholipase A(2) (PLA(2)) from a bullfrog pituitary fraction obtained during the purification of thyrotropin (TSH). Subsequently, partial amino acid sequence (N-terminal 45 amino acid residues) analysis revealed this protein to be identical to the N-terminal amino acid sequence of otoconin-22, the major protein of aragonitic otoconia in the Xenopus saccule. In this study we developed an antibody against the N-terminal peptide of the bullfrog protein and applied it for immunocytochemical study of the pituitary and its surrounding tissue. Western blotting analysis showed that this antibody recognizes a 20.4-kD protein that has a molecular mass close to that of otoconin-22. Immunohistochemical reaction with the antibody was not found in any anterior pituitary cells but was intense in the monolayer epithelial cells of the endolymphatic sac surrounding the pituitary gland, which is a major storage site of calcium carbonate in amphibians. An electron microscopic study revealed that the cuboidal cells in the endolymphatic sac contained large, polymorphic secretory granules in their apical cytoplasm. Immunogold particles indicating the presence of a PLA(2)-like protein were observed predominately in these secretory granules. These findings support the view that this PLA(2)-like protein obtained during purification of TSH was derived from the endolymphatic sac adhering to the pituitary and that this protein is a bullfrog otoconin. (J Histochem Cytochem 49:631-637, 2001) PMID:11304801

  13. Meal from tilapia filleting industrial waste in the feed of the bullfrog tadpoles (Rana Catesbeiana Shaw, 1802/ Inclusão de farinha de resíduos da indústria de filetagem de tilápias na alimentação de girinos de rã-touro (Rana Catesbeiana Shaw,1802

    Directory of Open Access Journals (Sweden)

    Cleiton Manske

    2007-08-01

    Full Text Available The objective of this experiment was to evaluate the inclusion of meal of tilapia industrial waster in bullfrog tadpoles’ diets (Rana Catesbeina Shaw, 1802. Two hundred fifty tadpoles with initial weight and length of 0,18 ± 0,05g and 2,50 ± 0,18 centimeters were used, respectively, they were used and distributed in 25 aquariums of 30 liter each in a complete randomized design with five treatments and five repetitions. The tadpoles were fed four times a day with diets containing 0, 5, 10 and 15% of inclusion of tilapia filleting and another diet with 0% of supplemented tilapia filleting with synthetic methionine, being supplied four times a day at ease. The experiment period was 30 days. The diets with tilapia filleting inclusion and methionine supplementation did not have influence in the final weight and length averages, feed survival and conversion of bullfrog tadpoles. It cam be used until 15% of tilapia filleting inclusion in the bullfrog tadpoles food. The synthetic methionine supplementation in diets for bullfrog tadpoles is not necessary in diets with levels over 0,47% of the total methionine.Este experimento objetivou avaliar a inclusão da farinha de resíduos de filetagem de tilápias (FT em rações para girinos de rã-touro (Rana Catesbeina Shaw,1802. Foram utilizados 250 girinos com peso e comprimento inicial de 0,18 ± 0,05g e 2,50 ± 0,18 cm, respectivamente, distribuídos em 25 aquários de 30 L cada, em um delineamento inteiramente casualizado com cinco tratamentos e cinco repetições. Os girinos foram alimentados quatro vezes ao dia, com rações contendo 0, 5, 10, 15% de inclusão de FT e outra ração com 0% de FT suplementada com metionina sintética, sendo fornecidas quatro vezes ao dia a vontade. O período do experimento foi de 30 dias. As rações com inclusão de FT e suplementação de metionina não influenciaram nas médias de peso final, comprimento final, sobrevivência e conversão alimentar dos girinos de r

  14. Cardiovascular, respiratory and metabolic responses to temperature and hypoxia of the winter frog Rana catesbeiana

    Directory of Open Access Journals (Sweden)

    Rocha P.L.

    1997-01-01

    Full Text Available The objective of the present study was to determine the effects of hypoxia and temperature on the cardiovascular and respiratory systems and plasma glucose levels of the winter bullfrog Rana catesbeiana. Body temperature was maintained at 10, 15, 25 and 35oC for measurements of breathing frequency, heart rate, arterial blood pressure, metabolic rate, plasma glucose levels, blood gases and acid-base status. Reducing body temperature from 35 to 10oC decreased (P<0.001 heart rate (bpm from 64.0 ± 3.1 (N = 5 to 12.5 ± 2.5 (N = 6 and blood pressure (mmHg (P<0.05 from 41.9 ± 2.1 (N = 5 to 33.1 ± 2.1 (N = 6, whereas no significant changes were observed under hypoxia. Hypoxia-induced changes in breathing frequency and acid-base status were proportional to body temperature, being pronounced at 25oC, less so at 15oC, and absent at 10oC. Hypoxia at 35oC was lethal. Under normoxia, plasma glucose concentration (mg/dl decreased (P<0.01 from 53.0 ± 3.4 (N = 6 to 35.9 ± 1.7 (N = 6 at body temperatures of 35 and 10oC, respectively. Hypoxia had no significant effect on plasma glucose concentration at 10 and 15oC, but at 25oC there was a significant increase under conditions of 3% inspired O2. The arterial PO2 and pH values were similar to those reported in previous studies on non-estivating Rana catesbeiana, but PaCO2 (37.5 ± 1.9 mmHg, N = 5 was 3-fold higher, indicating increased plasma bicarbonate levels. The estivating bullfrog may be exposed not only to low temperatures but also to hypoxia. These animals show temperature-dependent responses that may be beneficial since during low body temperatures the sensitivity of most physiological systems to hypoxia is reduced

  15. Efeito da temperatura e do fotoperíodo sobre o desenvolvimento do aparelho reprodutor de rã-touro (Rana catesbeiana Shaw, 1802 Effect of the temperature and the photoperiod on the development of bullfrog (Rana catesbeiana Shaw, 1802 reproduction apparel

    Directory of Open Access Journals (Sweden)

    Mario Roberto Chim Figueiredo

    2001-06-01

    combination of the temperatures of 26.0 and 29.0°C with photoperiods of 8/16, 12/12 and 16/8 h L/D, until they reach the gonadal maturity. Temperature interacted with photoperiod in its effects on the development of the reproductive organs of bullfrog. Temperature affected the diameter of the abdomen/distance relation between the eyes, with higher values calculated for 26°C. It was considered that the highest ovocites diameters are obtained under a temperature of 26.0°C, with photoperiod of 12.6/11.4 h L/D.

  16. De novo Transcriptome Assemblies of Rana (Lithobates catesbeiana and Xenopus laevis Tadpole Livers for Comparative Genomics without Reference Genomes.

    Directory of Open Access Journals (Sweden)

    Inanc Birol

    Full Text Available In this work we studied the liver transcriptomes of two frog species, the American bullfrog (Rana (Lithobates catesbeiana and the African clawed frog (Xenopus laevis. We used high throughput RNA sequencing (RNA-seq data to assemble and annotate these transcriptomes, and compared how their baseline expression profiles change when tadpoles of the two species are exposed to thyroid hormone. We generated more than 1.5 billion RNA-seq reads in total for the two species under two conditions as treatment/control pairs. We de novo assembled these reads using Trans-ABySS to reconstruct reference transcriptomes, obtaining over 350,000 and 130,000 putative transcripts for R. catesbeiana and X. laevis, respectively. Using available genomics resources for X. laevis, we annotated over 97% of our X. laevis transcriptome contigs, demonstrating the utility and efficacy of our methodology. Leveraging this validated analysis pipeline, we also annotated the assembled R. catesbeiana transcriptome. We used the expression profiles of the annotated genes of the two species to examine the similarities and differences between the tadpole liver transcriptomes. We also compared the gene ontology terms of expressed genes to measure how the animals react to a challenge by thyroid hormone. Our study reports three main conclusions. First, de novo assembly of RNA-seq data is a powerful method for annotating and establishing transcriptomes of non-model organisms. Second, the liver transcriptomes of the two frog species, R. catesbeiana and X. laevis, show many common features, and the distribution of their gene ontology profiles are statistically indistinguishable. Third, although they broadly respond the same way to the presence of thyroid hormone in their environment, their receptor/signal transduction pathways display marked differences.

  17. Acid-base regulation in tadpoles of Rana catesbeiana exposed to environmental hypercapnia

    DEFF Research Database (Denmark)

    Busk, Morten; Larsen, Erik Hviid; Jensen, Frank B.

    1997-01-01

    Tadpoles of Rana catesbeiana were exposed to different levels of environmental hypercapnia. The acid-base regulatory response differed from that in adult amphibians in showing a high degree of pH compensation in the extracellular fluid (65-85%) and complete compensation in the intracellular fluid......). It is suggested that the large bicarbonate efflux from the animal is a consequence of the dissolution of CaCO3 stores and the delayed adjustment of bicarbonate-retaining mechanisms. Re-exposure of tadpoles to hypercapnia after 1-3 weeks of normocapnic recovery only affected transepithelial fluxes of acid-base...

  18. Malaysian school engages in bullfrog and turtle farming

    OpenAIRE

    Dagoon, N. J.

    2000-01-01

    A brief description is given of the culture methods used in the Sepang Today Aquaculture Centre, a private aquafarming training school in Malaysia, regarding American bullfrog (Rana catesbeiana) and the soft-shelled turtle (Trionyx sinensis). Seed production, grow-out, marketing and future potential are discussed, referring to the school s training brochures for both culture methods.

  19. Influence of temperature on thyroid hormone signaling and endocrine disruptor action in Rana (Lithobates) catesbeiana tadpoles.

    Science.gov (United States)

    Hammond, S Austin; Veldhoen, Nik; Helbing, Caren C

    2015-08-01

    Thyroid hormones (THs) are essential for normal growth, development, and metabolic control in vertebrates. Their absolute requirement during amphibian metamorphosis provides a powerful means to detect and assess the impact of environmental contaminants on TH signaling in the field and laboratory. As poikilotherms, frogs can experience considerable temperature fluctuations. Previous work demonstrated that low temperature prevents precocious TH-dependent induction of metamorphosis. However, a shift to a permissive higher temperature allows resumption of the induced metamorphic program regardless of whether or not TH remains. We investigated the impact of temperature on the TH-induced gene expression programs of premetamorphic Rana (Lithobates) catesbeiana tadpoles following a single injection of 10pmol/g body wet weight 3,3',5-triiodothyronine (T3). Abundance profiles of several T3-responsive mRNAs in liver, brain, lung, back skin, and tail fin were characterized under permissive (24°C), nonpermissive (5°C), or temperature shift (5-24°C) conditions. While responsiveness to T3 was retained to varying degrees at nonpermissive temperature, T3 modulation of thibz occurred in all tissues at 5°C suggesting an important role for this transcription factor in initiation of T3-dependent gene expression programs. Low temperature immersion of tadpoles in water containing 10nM T3 and the nonsteroidal anti-inflammatory drug, ibuprofen, or the antimicrobial agent, triclosan, perturbed some aspects of the gene expression programs of tail fin and back skin that was only evident upon temperature shift. Such temporal uncoupling of chemical exposure and resultant biological effects in developing frogs necessitates a careful evaluation of environmental temperature influence in environmental monitoring programs. PMID:25583582

  20. Identification of organ-autonomous constituents of the molecular memory conferred by thyroid hormone exposure in cold temperature-arrested metamorphosing Rana (Lithobates) catesbeiana tadpoles.

    Science.gov (United States)

    Austin Hammond, S; Jackman, Kevin W; Partovi, Shireen H; Veldhoen, Nik; Helbing, Caren C

    2016-03-01

    Environmental temperature modulates thyroid hormone (TH)-dependent metamorphosis in some amphibian species. The North American bullfrog - Rana (Lithobates) catesbeiana - tadpole is naturally adapted to a wide range of temperatures over multiple seasons. Cold temperatures delay while warmer temperatures accelerate metamorphosis. Exogenous TH exposure of premetamorphic tadpoles results in a rapid precocious induction of metamorphosis at warm temperatures (20-25°C). The same exposure at cold temperatures (4-5°C) does not elicit an overt metamorphic response. However, a molecular memory of TH exposure is established such that cold, TH-exposed tadpoles returned to permissive warm temperatures will rapidly execute TH-induced genetic programs. Previous mRNA profiling has identified TH-regulated transcription factors encoded by thra, thrb, thibz, klf9, and cebp1 as components of the molecular memory after one week post-exposure. However, a further hierarchy may exist within the initiation phase since many gene transcripts demonstrated tissue-specific patterns. Whether the molecular memory is organ autonomous or requires additional modulating factors is unknown. Herein we examine tail fin and back skin and determine that thibz is the only transcript that is TH-responsive after 2 days post-exposure at low temperature in both tissues in the intact animal. In back skin, cebp1 is also TH-responsive under these conditions. Serum-free tail fin organ culture (C-Fin) reveals that the thibz response is organ autonomous whereas cultured back skin (C-Skin) results suggest that thibz and cebp1 require an additional factor for induction from elsewhere within the intact animal. Subsequent investigations are now possible to identify endogenous factors that modulate the molecular memory in intact animals. PMID:26795672

  1. Enzymatic activity of lipase in post-metamorphic phase bullfrogs Atividade enzimática da lipase em rã-touro na fase pós-metamórfica

    OpenAIRE

    Luís Gustavo Tavares Braga; Maria Goreti de Almeida Oliveira; William Cardoso Lima; Ricardo Frederico Euclydes

    2006-01-01

    The knowledge of the digestive system of bullfrogs is an important step for the determination of their nutritional requirements throughout growth phases. With the objective of evaluating the enzymatic activity of lipase in the intestinal content of bullfrogs (Rana catesbeiana Shaw, 1802), 100 animals with median weight of 3.6 g were distributed in stalls under controlled temperature and photoperiod. The frogs, selected at the post-metamorphic phase, received commercial extruded diet ad libitu...

  2. The importance of glucose for the freezing tolerance/intolerance of the anuran amphibians Rana catesbeiana and Bufo paracnemis

    Directory of Open Access Journals (Sweden)

    STEINER A. A.

    2000-01-01

    Full Text Available Several species of terrestrially hibernating frogs, turtles and insects have developed mechanisms, such as increased plasma glucose, anti-freeze proteins and antioxidant enzymes that resist to freezing, for survival at subzero temperatures. In the present study, we assessed the importance of glucose to cryoresistance of two anuran amphibians: the frog Rana catesbeiana and the toad Bufo paracnemis. Both animals were exposed to -2ºC for measurements of plasma glucose levels, liver and muscle glycogen content, haematocrit and red blood cell volume. Frogs survived cold exposure but toads did not. Blood glucose concentration increased from 40.35 ± 7.25 to 131.87 ± 20.72 mg/dl (P < 0.01 when the frogs were transferred from 20 to -2ºC. Glucose accumulation in response to cold exposition in the frogs was accompanied by a decrease (P < 0.05 in liver glycogen content from 3.94 ± 0.42 to 1.33 ± 0.36 mg/100 mg tissue, indicating that liver carbohydrate reserves were probably the primary carbon source of glucose synthesis whereas muscle carbohydrate seems unimportant. In the toads, the cold-induced hyperglycaemia was less (P < 0.05 pronounced (from 27.25 ± 1.14 to 73.72 ± 13.50 mg/dl and no significant change could be measured in liver or muscle glycogen. Cold exposition had no effect on the haematocrit of the frogs but significantly reduced (P < 0.01 the haematocrit of toads from 20.0 ± 2.1% to 5.8 ± 1.7% due to a decreased red blood cell volume (from 1532 ± 63 to 728 ± 87 mm³. When toads were injected with glucose, blood glucose increased to levels similar to those of frogs and haematocrit did not change, but this failed to make them cryoresistent. In conclusion, the lack of cold-induced glucose catabolism may not be the only mechanism responsible for the freeze intolerance of Bufo paracnemis, a freeze-intolerant species.

  3. Evaluation of the effects of titanium dioxide nanoparticles on cultured Rana catesbeiana tailfin tissue

    Directory of Open Access Journals (Sweden)

    S. Austin eHammond

    2013-11-01

    Full Text Available Nanoparticles (NPs, materials that have one dimension less than 100 nm, are used in manufacturing, health and food products, and consumer products including cosmetics, clothing and household appliances. Their utility to industry is derived from their high surface-area-to-volume ratios and physico-chemical properties distinct from their bulk counterparts, but the near-certainty that NPs will be released into the environment raises the possibility that they could present health risks to humans and wildlife. The thyroid hormones (THs, thyroxine and 3,3’,5-triiodothyronine (T3, are involved in development and metabolism in vertebrates including humans and frogs. Many of the processes of anuran metamorphosis are analogous to human post-embryonic development and disruption of TH action can have drastic effects. These shared features make the metamorphosis of anurans an excellent model for screening for endocrine disrupting chemicals (EDCs. We used the cultured tailfin (C-fin assay to examine the exposure effects of 0.1-10 nM (~8-800 ng/L of three types of ~20 nm TiO2 NPs (P25, M212, M262 and micron-sized TiO2 (μTiO2 ±10 nM T3. The actual Ti levels were 40.9 – 64.7% of the nominal value. Real-time quantitative polymerase chain reaction (QPCR was used to measure the relative amounts of mRNA transcripts encoding TH-responsive thyroid hormone receptors (thra and thrb and Rana larval keratin type I (rlk1, as well as the cellular stress-responsive heat shock protein 30 kDa (hsp30, superoxide dismutase (sod, and catalase (cat. The levels of the TH-responsive transcripts were largely unaffected by any form of TiO2. Some significant effects on stress-related transcripts were observed upon exposure to micron-sized TiO2, P25 and M212 while no effect was observed with M262 exposure. Therefore the risk of adversely affecting amphibian tissue by disrupting TH-signalling or inducing cellular stress is low for these compounds relative to other previously

  4. Evaluation of the effects of titanium dioxide nanoparticles on cultured Rana catesbeiana tailfin tissue

    Science.gov (United States)

    Hammond, S. Austin; Carew, Amanda C.; Helbing, Caren C.

    2013-01-01

    Nanoparticles (NPs), materials that have one dimension less than 100 nm, are used in manufacturing, health, and food products, and consumer products including cosmetics, clothing, and household appliances. Their utility to industry is derived from their high surface-area-to-volume ratios and physico-chemical properties distinct from their bulk counterparts, but the near-certainty that NPs will be released into the environment raises the possibility that they could present health risks to humans and wildlife. The thyroid hormones (THs), thyroxine, and 3,3′,5-triiodothyronine (T3), are involved in development and metabolism in vertebrates including humans and frogs. Many of the processes of anuran metamorphosis are analogous to human post-embryonic development and disruption of TH action can have drastic effects. These shared features make the metamorphosis of anurans an excellent model for screening for endocrine disrupting chemicals (EDCs). We used the cultured tailfin (C-fin) assay to examine the exposure effects of 0.1–10 nM (~8–800 ng/L) of three types of ~20 nm TiO2 NPs (P25, M212, M262) and micron-sized TiO2 (μ TiO2) ±10 nM T3. The actual Ti levels were 40.9–64.7% of the nominal value. Real-time quantitative polymerase chain reaction (QPCR) was used to measure the relative amounts of mRNA transcripts encoding TH-responsive THs receptors (thra and thrb) and Rana larval keratin type I (rlk1), as well as the cellular stress-responsive heat shock protein 30 kDa (hsp30), superoxide dismutase (sod), and catalase (cat). The levels of the TH-responsive transcripts were largely unaffected by any form of TiO2. Some significant effects on stress-related transcripts were observed upon exposure to micron-sized TiO2, P25, and M212 while no effect was observed with M262 exposure. Therefore, the risk of adversely affecting amphibian tissue by disrupting TH-signaling or inducing cellular stress is low for these compounds relative to other previously-tested NPs. PMID

  5. 黑斑蛙、虎纹蛙和牛蛙皮肤的比较组织学%Comparative Histology of the Skin of Rana Nigromaculata,Rana Rugulosa and Rana Catesbeiana

    Institute of Scientific and Technical Information of China (English)

    李洋; 金磊; 李昌春; 唐宝将; 张盛周

    2009-01-01

    应用H.E和V.G胶原染色法对黑斑蛙(Rana nigromaculata)、虎纹蛙(Rana rugulosa)和牛蛙(Rana catesbeiana)皮肤进行了组织学观察和参数测量与比较.结果表明:三种蛙皮肤组织结构相似,但皮肤厚度、各组织层相对厚度及腺体密度存在较明显的种间差异和部位差异.虎纹蛙的皮肤最厚(0.44-0.68mm),牛蛙其次(0.28-0.60mm),黑斑蛙最薄(0.19-0.38mm);在三种蛙中,黑斑蛙躯体多数部位表皮相对厚度为15.1%-22.6%,较虎纹蛙(10.9%-17.7%)和牛蛙(9.9%-21.8%)厚.虎纹蛙和牛蛙皮肤胶原纤维层相对厚度分别为59.9%-68.7%和51.6%-75.3%,较黑斑蛙(44.4%-69.0%)厚;黑斑蛙和虎纹蛙躯体多数部位的颗粒腺密度(4.5-23.1个/mm2;8.9-25.3个/mm2)和粘液腺(54.1-152.2个/mm2;68.6-127.5个/mm2)较牛蛙(1.4-10.8个/mm2;16.8-39.3个/mm2)高.研究结果可供蛙类皮肤的合理开发利用参考.

  6. Enzymatic activity of lipase in post-metamorphic phase bullfrogs

    Directory of Open Access Journals (Sweden)

    Braga Luís Gustavo Tavares

    2006-01-01

    Full Text Available The knowledge of the digestive system of bullfrogs is an important step for the determination of their nutritional requirements throughout growth phases. With the objective of evaluating the enzymatic activity of lipase in the intestinal content of bullfrogs (Rana catesbeiana Shaw, 1802, 100 animals with median weight of 3.6 g were distributed in stalls under controlled temperature and photoperiod. The frogs, selected at the post-metamorphic phase, received commercial extruded diet ad libitum throughout the 87-day experiment. The collections of the intestinal content were performed by the desensitization of the frogs in ice and water at 0ºC and subsequent isolation of the small intestine. Determination of lipase activity was performed with a commercial enzymatic kit (Lipase-Bioclin, MG, Brazil, first measured in samples taken at day three (3.46 UI. During the initial phase the bullfrog possesses low lipase hydrolysis capacity was found, having a specific activity of 217 UI mg-1. In the subsequent period both lipase activity and specific lipase activity continuously increased. Lipase activity as a function of bullfrog weight fell after day twenty and reached 0.33 UI g-1, for frogs of medium weight (179 g. Feed for bullfrogs at the post-metamorphic phase weighing more than 10 g can have larger amounts of ingredients containg lipids, due to the increased digestive capacity of these frogs.

  7. Analysis of the Rana catesbeiana tadpole tail fin proteome and phosphoproteome during T3-induced apoptosis: identification of a novel type I keratin

    Directory of Open Access Journals (Sweden)

    Helbing Caren C

    2007-08-01

    Full Text Available Abstract Background Thyroid hormones (THs are vital in the maintenance of homeostasis and in the control of development. One postembryonic developmental process that is principally regulated by THs is amphibian metamorphosis. This process has been intensively studied at the genomic level yet very little information at the proteomic level exists. In addition, there is increasing evidence that changes in the phosphoproteome influence TH action. Results Here we identify components of the proteome and phosphoproteome in the tail fin that changed within 48 h of exposure of premetamorphic Rana catesbeiana tadpoles to 10 nM 3,5,3'-triiodothyronine (T3. To this end, we developed a cell and protein fractionation method combined with two-dimensional gel electrophoresis and phosphoprotein-specific staining. Altered proteins were identified using mass spectrometry (MS. We identified and cloned a novel Rana larval type I keratin, RLK I, which may be a target for caspase-mediated proteolysis upon exposure to T3. In addition, the RLK I transcript is reduced during T3-induced and natural metamorphosis which is consistent with a larval keratin. Furthermore, GILT, a protein involved in the immune system, is changed in phosphorylation state which is linked to its activation. Using a complementary MS technique for the analysis of differentially-expressed proteins, isobaric tags for relative and absolute quantitation (iTRAQ revealed 15 additional proteins whose levels were altered upon T3 treatment. The success of identifying proteins whose levels changed upon T3 treatment with iTRAQ was enhanced through de novo sequencing of MS data and homology database searching. These proteins are involved in apoptosis, extracellular matrix structure, immune system, metabolism, mechanical function, and oxygen transport. Conclusion We have demonstrated the ability to derive proteomics-based information from a model species for postembryonic development for which no genome

  8. Efeito do alecrim na defumação da carne de rã (Rana catesbeiana: características sensoriais, composição e rendimento The effect of rosemary on the smoked frog meat (Rana catesbeiana: sensory characteristics, composition, and carcass yield

    Directory of Open Access Journals (Sweden)

    Michele Ferreira Assis

    2009-09-01

    Full Text Available Este trabalho avaliou o efeito do alecrim na qualidade da carne de rã (Rana catesbeiana defumada, por meio da análise das características sensoriais, da composição centesimal e do rendimento. Após o abate e a evisceração, as carcaças foram imersas em solução de salmoura (20% numa proporção de 2:1 (volume da salmoura/peso. Posteriormente, elas foram banhadas em azeite e defumadas a uma temperatura de 50 a 90 °C. O delineamento experimental foi inteiramente casualizado, com 2 tratamentos (T1 = Carcaça de rã defumada com alecrim; T2 = Carcaça de rã defumada sem alecrim com 16 repetições. Na análise estatística, foi utilizado o programa SAEG 2004, com 5% de significância. As carcaças defumadas apresentaram valores médios de proteína bruta (28,39%, lipídios totais (5,13% e cinzas (2,79% superiores comparados aos das carcaças in natura (23,41; 2,29 e 0,85%. Não houve efeito significativo do alecrim na composição centesimal. A carcaça de rã defumada com alecrim apresentou melhor aceitação quanto ao aroma. Nas demais características sensoriais, a presença do alecrim não interferiu nos resultados. A carne de rã pode ser defumada com e sem alecrim, sem interferir na aceitabilidade do produto.This work studied the effect of rosemary on the quality of smoked frog meat (Rana catesbeiana through the analysis of sensory characteristics, centesimal composition, and processing performance. The carcasses were immersed in a solution of brine (20%, in the proportion of 2:1 (volume of brine/weight, soaked in olive oil and smoked at a temperature range from 50 to 90 °C. The experimental delineation was entirely casual with 2 treatments (T1 = frog carcass with rosemary; T2 = frog carcass without rosemary with 16 repetitions. For the statistical analysis, the SAEG 2004 program, with 5% of significance was used. The smoked carcasses presented medium values of rude protein (28,39%, total lipids (5,13%, and ashes (2

  9. Development of Hepatozoon caimani (Carini, 1909 Pessôa, De Biasi & De Souza, 1972 in the Caiman Caiman c. crocodilus, the frog Rana catesbeiana and the mosquito Culex fatigans

    Directory of Open Access Journals (Sweden)

    Ralph Lainson

    2003-01-01

    Full Text Available The sporogony of Hepatozoon caimani has been studied, by light microscopy, in the mosquito Culex fatigans fed on specimens of the caiman Caiman c. crocodilus showing gametocytes in their peripheral blood. Sporonts iniciate development in the space between the epithelium of the insect gut and the elastic membrane covering the haemocoele surface of the stomach. Sporulating oocysts are clustered on the gut, still invested by the gut surface membrane. Fully mature oocysts were first seen 21 days after the blood-meal. No sporogonic stages were found in some unidentified leeches fed on an infected caiman, up to 30 days following the blood-meal. When mosquitoes containing mature oocysts were fed to frogs (Leptodactylus fuscus and Rana catesbeiana, cysts containing cystozoites developed in the internal organs, principally the liver. Feeding these frogs to farm-bred caimans resulted in the appearance of gametocytes in their peripheral blood at some time between 59 and 79 days later, and the development of tissue cysts in the liver, spleen, lungs and kidneys. Transmission of the parasite was also obtained by feeding young caimans with infected mosquitoes and it is suggested that both methods occur in nature. The finding of similar cysts containing cystozoites in the semi-aquatic lizard Neusticurus bicarinatus, experimentally fed with infected C. fatigans, suggests that other secondary hosts may be involved.

  10. Molecular cloning of otoconin-22 complementary deoxyribonucleic acid in the bullfrog endolymphatic sac: effect of calcitonin on otoconin-22 messenger ribonucleic acid levels.

    Science.gov (United States)

    Yaoi, Yuichi; Suzuki, Masakazu; Tomura, Hideaki; Sasayama, Yuichi; Kikuyama, Sakae; Tanaka, Shigeyasu

    2003-08-01

    Anuran amphibians have a special organ called the endolymphatic sac (ELS), containing many calcium carbonate crystals, which is believed to have a calcium storage function. The major protein of aragonitic otoconia, otoconin-22, which is considered to be involved in the formation of calcium carbonate crystals, has been purified from the saccule of the Xenopus inner ear. In this study, we cloned a cDNA encoding otoconin-22 from the cDNA library constructed for the paravertebral lime sac (PVLS) of the bullfrog, Rana catesbeiana, and sequenced it. The bullfrog otoconin-22 encoded a protein consisting of 147 amino acids, including a signal peptide of 20 amino acids. The protein had cysteine residues identical in a number and position to those conserved among the secretory phospholipase A(2) family. The mRNA of bullfrog otoconin-22 was expressed in the ELS, including the PVLS and inner ear. This study also revealed the presence of calcitonin receptor-like protein in the ELS, with the putative seven-transmembrane domains of the G protein-coupled receptors. The ultimobranchialectomy induced a prominent decrease in the otoconin-22 mRNA levels of the bullfrog PVLS. Supplementation of the ultimobranchialectomized bullfrogs with synthetic salmon calcitonin elicited a significant increase in the mRNA levels of the sac. These findings suggest that calcitonin secreted from the ultimobranchial gland, regulates expression of bullfrog otoconin-22 mRNA via calcitonin receptor-like protein on the ELS, thereby stimulating the formation of calcium carbonate crystals in the lumen of the ELS. PMID:12865304

  11. Within-individual variation in bullfrog vocalizations: Implications for a vocally mediated social recognition system

    Science.gov (United States)

    Bee, Mark A.

    2004-12-01

    Acoustic signals provide a basis for social recognition in a wide range of animals. Few studies, however, have attempted to relate the patterns of individual variation in signals to behavioral discrimination thresholds used by receivers to discriminate among individuals. North American bullfrogs (Rana catesbeiana) discriminate among familiar and unfamiliar individuals based on individual variation in advertisement calls. The sources, patterns, and magnitudes of variation in eight acoustic properties of multiple-note advertisement calls were examined to understand how patterns of within-individual variation might either constrain, or provide additional cues for, vocal recognition. Six of eight acoustic properties exhibited significant note-to-note variation within multiple-note calls. Despite this source of within-individual variation, all call properties varied significantly among individuals, and multivariate analyses indicated that call notes were individually distinct. Fine-temporal and spectral call properties exhibited less within-individual variation compared to gross-temporal properties and contributed most toward statistically distinguishing among individuals. Among-individual differences in the patterns of within-individual variation in some properties suggest that within-individual variation could also function as a recognition cue. The distributions of among-individual and within-individual differences were used to generate hypotheses about the expected behavioral discrimination thresholds of receivers. .

  12. Developmental expression of otoconin-22 in the bullfrog endolymphatic sac and inner ear.

    Science.gov (United States)

    Yaoi, Yuichi; Onda, Tomoaki; Hidaka, Yoshie; Yajima, Shinya; Suzuki, Masakazu; Tanaka, Shigeyasu

    2004-05-01

    In amphibians, calcium carbonate crystals are present in the endolymphatic sac and the inner ear. The formation of these crystals is considered to be facilitated by a protein called otoconin-22. We examined the spatial and temporal expression of otoconin-22 during the development of the bullfrog (Rana catesbeiana) using RT-PCR, in situ hybridization (ISH), and immunofluorescence techniques. By RT-PCR, otoconin-22 mRNA was first detected in embryos at Shumway stage 20, and this expression pattern continues in late stages. The first otoconin-22 mRNA-positive reaction was detected in stage 22 embryos in the placode of the endolymphatic sac. Otoconin-22 protein was observed in the epithelial cells of the endolymphatic sac at stage 24. On the other hand, a whole-mount ISH technique showed the first expression of otoconin-22 mRNA in the inner ear, in addition to the endolymphatic sac, at the mid-phase of Shumway stage 25. We discuss the role of otoconin-22 in the formation of calcium carbonate crystals in the endolymphatic sac and inner ear. PMID:15100243

  13. Spontaneous oral chytridiomycosis in wild bullfrog tadpoles in Japan.

    Science.gov (United States)

    Kadekaru, Sho; Tamukai, Ken-Ichi; Tominaga, Atsushi; Goka, Koichi; Une, Yumi

    2016-05-01

    Batrachochytrium dendrobatidis (Bd) infects Anuran larvae (tadpole) mouthparts and causes oral chytridiomycosis, which can be diagnosed in tadpoles by detecting mouthparts deformities. However, oral chytridiomycosis may or may not be observable, depending on species, tadpole stage and season, and has never been reported in Japan. We aimed to observe oral chytridiomycosis characteristics in bullfrog (Lithobates catesbeiana) tadpoles, determine associated pathologic features and investigate the usability of bullfrog tadpoles in Japanese Bd field surveys. Wild-captured bullfrog tadpole mouthparts were examined macroscopically, histopathologically and by molecular biological examination. Macroscopic lesions were observed in 21 of 59 tadpole mouthparts. Lesions were most frequently located in the lower jaw sheaths and were mainly recognized by partial depigmentation (11 tadpoles; some were completely depigmented) and thinning of the pigmented layer (10 tadpoles). Partial defects of the tips and blunt cutting edges of the jaw sheaths were observed with severe jaw sheath depigmentation. Whitened tooth rows were observed in 7 tadpoles. Histologically, the stratified epithelium (pigmented epithelium) showed partial or diffuse hypopigmentation or pigment loss. Irregular stratified epithelium thickening with hyperkeratosis or parakeratosis was observed in the jaw sheaths. Bd infection was confirmed in 20 of 21 tadpoles presenting jaw sheath deformities, by histopathological examination and/or nested polymerase chain reaction. Depigmentation and thinning of the pigmented layers of jaw sheaths were associated with Bd infection. Thus, diagnosis of Bd infection by macroscopic observation of bullfrog tadpole mouthparts is feasible. This is the first report of oral chytridiomycosis in wild bullfrog tadpoles in Japan. PMID:26685882

  14. Metabolism of thyroxine in Rana catesbeiana tadpoles during metamorphic climax

    International Nuclear Information System (INIS)

    Previous studies have indicated that premetamorphic tadpoles do not convert T4 to T3 to a measurable extent (1). The present study was performed to determine whether a T4 5'-monodeiodinating system is acquired at later stages of development. [125I]T4 metabolism in vivo was determined in tadpoles at most stages of prometamorphosis and metamorphic climax and, for comparison, in premetamorphic tadpoles. The conversion of [125I]T4 to [125I]T3, as indicated by the presence of an 125I-labeled product in serum and liver preparations that cochromatographed with carrier T3, was sometimes observed in tadpoles near the end of prometamorphosis and was always evident in tadpoles that were either undergoing or had completed metamorphic climax. However, during this phase, no correlation could be drawn between the extent of T3 production and morphological development. The formation of T3 from T4 in vivo was significantly decreased in tadpoles pretreated with propylthiouracil. The T45'-monodeiodinating system could be induced in premetamorphic tadpoles by injecting them with either T4 or T3. This finding together with the observation that normal acquisition of this system occurs at the time when endogenous T4 and T3 levels are rising rapidly suggest that its development is under the control of the thyroid hormones

  15. Physiological response of American bullfrog tadpoles to stressor conditions of capture and hypoxia Resposta fisiológica de girinos de rã-touro americana submetidos aos mecanismos estressores de captura e hipóxia.

    Directory of Open Access Journals (Sweden)

    Guilherme C Rocha

    2010-10-01

    Full Text Available The American bullfrog (Rana catesbeiana, recently named Lithobates catesbeianus is currently farmed for commercial purposes throughout various regions of Brazil. Stressful situations such as problems of management, inadequate facilities and environmental changes with consequent reduction of immunity are common in intensive production. The assessments of these situations of stress allow us detect these problems decreasing the injuries causes by confinement. The main objective of this study was to use the biological markers of plasma cortisol and glucose level and hematological parameters to evaluate the response of bullfrog tadpoles submitted to stressed mechanisms of capture and hypoxia. The animals were subjected to three treatments: stress due to individual capture with a hand net; stress due to batch capture with a hand net; and stress due to capture by emptying. The results obtained demonstrated that there were no statistically significant differences in the parameters tested when comparing the treatments with and without exposure to air (normoxia and hypoxia. Based on these results we can conclude that the stressful stimuli tested were not adequate to alter the biomarker tested. For the cortisol, probably this should have occurred due to the synergistic action between this hormone and thyroxin, which induces metamorphosis in these animals.A rã-touro americana (Rana catesbeiana recentemente denominada Lithobates catesbeianus é cria da com propósito comercial em várias regiões do Brasil. Situações estressantes tais como problemas de manejo, criação inadequada e alterações ambientais com consequente redução da imunidade são comuns em produções intensivas. A avaliação destas situações de estresse permite-nos detectar estes probemas e diminuir as injurias causadas pelo confinamento. O principal objetivo deste estudo foi utilizar os marcadores biológicos de cortisol, glicemia e dados hematológicos para avaliar a resposta de

  16. Comparative transduction mechanisms of hair cells in the bullfrog utriculus. II. Sensitivity and response dynamics to hair bundle displacement

    Science.gov (United States)

    Baird, R. A.

    1994-01-01

    1. Hair cells in whole-mount in vitro preparations of the utricular macula of the bullfrog (Rana catesbeiana) were selected according to their macular location and hair bundle morphology. The sensitivity and response dynamics of selected hair cells to natural stimulation were examined by recording their voltage responses to step and sinusoidal hair bundle displacements applied to their longest stereocilia. 2. The voltage responses of 31 hair cells to sinusoidal hair bundle displacements were characterized by their gains and phases, taken with respect to peak hair bundle displacement. The gains of Type B and Type C cells at both 0.5 and 5.0 Hz were markedly lower than those of Type F and Type E cells. Phases, with the exception of Type C cells, lagged hair bundle displacement at 0.5 Hz. Type C cells had phase leads of 25-40 degrees. At 5.0 Hz, response phases in all cells were phase lagged with respect to those at 0.5 Hz. Type C cells had larger gains and smaller phase leads at 5.0 Hz than at 0.5 Hz, suggesting the presence of low-frequency adaptation. 3. Displacement-response curves, derived from the voltage responses to 5.0-Hz sinusoids, were sigmoidal in shape and asymmetrical, with the depolarizing response having a greater magnitude and saturating less abruptly than the hyperpolarizing response. When normalized to their largest displacement the linear ranges of these curves varied from hair bundle to linear range and sensitivity were predicted from realistic models of utricular hair bundles created using morphological data obtained from light and electron microscopy. Three factors, including 1) the inverse ratio of the lengths of the kinocilium and longest stereocilia, representing the lever arm between kinociliary and stereociliary displacement; 2) tip link extension/linear displacement, largely a function of stereociliary height and separation; and 3) stereociliary number, an estimate of the number of transduction channels, were considered in this analysis

  17. Comparative transduction mechanisms of hair cells in the bullfrog utriculus. II. Sensitivity and response dynamics to hair bundle displacement

    Science.gov (United States)

    Baird, R. A.

    1994-01-01

    1. Hair cells in whole-mount in vitro preparations of the utricular macula of the bullfrog (Rana catesbeiana) were selected according to their macular location and hair bundle morphology. The sensitivity and response dynamics of selected hair cells to natural stimulation were examined by recording their voltage responses to step and sinusoidal hair bundle displacements applied to their longest stereocilia. 2. The voltage responses of 31 hair cells to sinusoidal hair bundle displacements were characterized by their gains and phases, taken with respect to peak hair bundle displacement. The gains of Type B and Type C cells at both 0.5 and 5.0 Hz were markedly lower than those of Type F and Type E cells. Phases, with the exception of Type C cells, lagged hair bundle displacement at 0.5 Hz. Type C cells had phase leads of 25-40 degrees. At 5.0 Hz, response phases in all cells were phase lagged with respect to those at 0.5 Hz. Type C cells had larger gains and smaller phase leads at 5.0 Hz than at 0.5 Hz, suggesting the presence of low-frequency adaptation. 3. Displacement-response curves, derived from the voltage responses to 5.0-Hz sinusoids, were sigmoidal in shape and asymmetrical, with the depolarizing response having a greater magnitude and saturating less abruptly than the hyperpolarizing response. When normalized to their largest displacement the linear ranges of these curves varied from Sensitivity, defined as the slope of the normalized displacement-response curve, was inversely correlated with linear range. 4. The contribution of geometric factors associated with the hair bundle to linear range and sensitivity were predicted from realistic models of utricular hair bundles created using morphological data obtained from light and electron microscopy. Three factors, including 1) the inverse ratio of the lengths of the kinocilium and longest stereocilia, representing the lever arm between kinociliary and stereociliary displacement; 2) tip link extension

  18. Alterações histopatológicas em girinos de rã-touro alimentados com rações comerciais de diferentes níveis protéicos Histopathological alterations in bullfrog tadpoles fed commercial diets with three levels of crude protein

    Directory of Open Access Journals (Sweden)

    José Teixeira de Seixas Filho

    2008-12-01

    Full Text Available Realizaram-se necropsia e exame histopatológico de girinos de rã-touro (Rana catesbeiana alimentados com rações comerciais formuladas com 32, 36, 45 ou 55% de proteína bruta (PB visando estabelecer a relação entre o nível de proteína bruta da ração e a sanidade do animal. Na necropsia, os girinos não apresentaram externamente nenhuma alteração aparente, no entanto, o fígado dos animais, em todos os níveis de proteína bruta, apresentou-se de cor palha e manchado. Na análise histopatológica, observaram-se fígados com rarefação e degeneração celular protéica, intestinos com colite e achatamento das microvilosidades; baço com hiperplasia linfocitária; coração sem nenhuma alteração; rins com glomerulonefrite e áreas de tubulonefroses; gastrite mononuclear e hiperplasia e hipertrofia dos linfonodos regionais. Em todos os órgãos, verificou-se depósito de hemossiderina. Essas lesões sugerem quadro degenerativo nutricional, com desenvolvimento de processos inflamatórios, se difundindo para todos os órgãos. Os resultados sugerem que os animais foram alimentados com rações com proteínas de baixo valor biológico, portanto, de má qualidade, o que comprometeu a sanidade e o desempenho dos animais. Estudos complementares são necessários para compreensão do comportamento bioquímico de rãs-touro na fase de girino visando à nutrição adequada desses animais.Necropsy and histological examination were made on bullfrog (Rana catesbeiana tadpoles fed commercial rations with 32, 36, 45 or 55% crude protein (CP to establish the relationship between dietary crude protein and health of the animal. In the necropsy, the tadpoles did not show externally any changes, however, the liver of animals at all crude protein levels, presented a straw color and stained. Histological analysis showed livers with rarefaction and degeneration of cell protein, intestines, with colitis and flattening of microvilli, spleen with lymphocyte

  19. Avaliação histológica do intestino médio, do fígado e do pâncreas de girinos de rã-touro alimentados com rações comerciais formuladas com três níveis de proteína bruta Histological evaluation of midgut, liver and pancreas of bullfrog tadpoles fed commercial diets with three levels of crude protein

    Directory of Open Access Journals (Sweden)

    José Teixeira de Seixas Filho

    2008-12-01

    Full Text Available Avaliou-se o desenvolvimento do intestino médio, do fígado e do pâncreas de girinos de rã-touro (Rana catesbeiana alimentados com ração comercial com 22, 24 ou 28% de proteína bruta (PB. Utilizaram-se 360 girinos com 15 dias de vida, provenientes de mesma desova, distribuídos em caixas com 30 L de água, em densidade de 1 girino/L, mantidas a 25°C (±1ºC, constituindo um delineamento experimental completamente casualizado, com quatro repetições. A partir do 9º dia e até o 48º dia de alimentação, os órgãos (intestino médio, fígado e pâncreas de três girinos de cada grupo foram fixados em solução histológica de Bouin para coloração por hematoxilina e eosina. A presença de tecido conjuntivo extremamente frouxo nas alças intestinais dos girinos sugeriu situação provisória para a mudança da arquitetura intestinal após a metamorfose. Nesse período, observou-se aumento no número de células caliciformes e de microvilosidades e, no 25º dia, verificou-se a presença de células hepáticas, com arranjo glandular mais compacto, o que sugere funcionalidade e confirma os melhores resultados de desempenho obtidos a partir desse período nos girinos alimentados com as rações com maior nível protéico. No 35º dia, observou-se a estrutura do fígado bilobado, com sinais de desorganização, o que indica rarefação celular protéica, decorrente de mau aproveitamento da proteína da ração. Novos estudos são necessários para continuidade aos esclarecimentos sobre as características fisiológicas de rãs-touro na fase de girino.The development of midgut, liver and pancreas bullfrog tadpoles (Rana catesbeiana fed commercial diets with 22, 24 or 28% of crude protein (CP was evaluated. A total of 360 tadpoles, 15 days old, from the same spawning, was allotted to 30 L-boxes, using a density of 1 tadpole/L, kept at 25 °C (±1°C. A completely randomized experimental design with four replications was used. Three tadpoles of

  20. BULLFROG HEMOGRAM UNDER MANAGEMENT STRESS

    OpenAIRE

    Patrícia Coelho Teixeira; Irene Bastos Franceschini Vicentini; Claudia Maris Ferreira; Fernanda Menezes França; Isabela Cristina Antunes da Costa Bordon; Maria José Tavares Ranzani-Paiva

    2015-01-01

    Stress is one of the major obstacles in frog culture and can be caused by factors such as inappropriate farming systems; inadequate management among other situations. The objective of the present study was to assess the hemogram, erythrogram and leukogram of bullfrogs (L. catesbeianus) when exposed to stress caused by different types of management: density and handling (manipulation), developed in the laboratory and repeated in the field for the appropriate comparisons in a experimental perio...

  1. Cotransport of H+, lactate and H2O by membrane proteins in retinal pigment epithelium of bullfrog

    DEFF Research Database (Denmark)

    Zeuthen, T; Hamann, S; la Cour, M; Hamann, Steffen Ellitsgaard

    solution concentration and/or osmolarity. 3. Two parallel pathways for water transport were identified across the retinal membrane, an osmotic one with a hydraulic water permeability of 3.2 x 10(-4) cm s-1 (osmol l-1)-1 and one which depended on the presence of lactate. 4. Addition of sodium lactate to the......1. The interaction between H+, lactate and H2O fluxes in the retinal membrane of the pigment epithelium from bullfrog Rana catesbiana was studied by means of ion-selective micro-electrodes. 2. Changes in intracellular pH and cell volume were recorded in response to abrupt changes in retinal...

  2. Conboy Lake - Bullfrog and Bullhead Control

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This proposal is to support two AmeriCorps interns for 24 weeks to work on removal of American bullfrogs and brown bullhead to benefit Oregon spotted frogs, a...

  3. Rana dijagnoza reumatoidnog artritisa

    OpenAIRE

    Babić-Naglić, Đurđica; Žagar, Iva

    2006-01-01

    Reumatoidni artritis (RA) kronična je multisistemska bolest s najtežim posljedicama na sustavu za kretanje. Danas je pravilo dobre kliničke prakse postaviti dijagnozu RA u preerozivnoj fazi i rano primijeniti diferentne lijekove. Rana dijagnoza RA postavlja se na temelju ciljane kliničke, serološke, imunogenske i radiološke obrade. Na temelju definiranih parametara, klinički je potrebno precizno odrediti aktivnost bolesti. Reumatoidni faktor i anticitrulinska protutijela (anti-CCP) su vrlo...

  4. 虎纹蛙消化道肥大细胞类胰蛋白酶免疫组化研究%STUDY ON TRYPTASE IN THE MAST CELL IN THE DIGESTIVE TRACT OF INDIAN BULLFROG (RANA TIGRINA RUGULOSA) BY AN IMMUNOHISTOCHEMICAL METHOD

    Institute of Scientific and Technical Information of China (English)

    林旋; 王寿昆; 陈梅芳; 林树根; 黄玉章

    2010-01-01

    研究采用小鼠抗人肥大细胞类胰蛋白酶单克隆抗体AA1,应用Elivision~(TM)plus免疫组化染色法对虎纹蛙(Rana tigrina rugulosa)消化道组织中类胰蛋白酶阳性肥大细胞存在的可能性进行研究.研究发现单克隆抗体AA1可与中性缓冲福马林液同定的虎纹蛙组织的肥大细胞获得良好的交叉反应,类胰蛋白酶阳性细胞胞浆染成棕黄色.证实虎纹蛙肥大细胞胞浆颗粒中也存在类胰蛋白酶.虎纹蛙组织中AA1免疫染色阳性细胞的分布,与AB/SO和改良甲苯胺兰染色阳性细胞的分布存在较大的差异:虎纹蛙类胰蛋白酶阳性细胞数量很少,且阳性反应比人胃癌间质肥大细胞弱,主要见于黏膜型肥大细胞(MMC)分布区域,如消化道黏膜上皮下方和同有层,少量分布于肠绒毛基底部及食管腺和胃腺周围.而在结缔组织型肥大细胞(CTMC)分布区域.如消化道黏膜下层结缔组织中却未见类胰蛋白酶阳性细胞.AB/SO和改良甲苯胺兰染色阳性细胞数量多.广泛分布于消化道黏膜固有层、黏膜下层、腺体之间、肌间及外膜结缔组织,说明并不是所有的虎纹蛙肥大细胞都含有类胰蛋白酶.很有可能是虎纹蛙 MMC 中含有类胰蛋白酶.而CTMC中不含类胰蛋白酶.虎纹蛙类胰蛋白酶阳性细胞数量很少.且阳性反应比人胃癌间质肥大细胞弱,说明虎纹蛙肥大细胞胞浆颗粒类胰蛋白酶含量较少,虎纹蛙属于低等脊椎动物,可能与生物进化水平较低有关,有待进一步研究.

  5. BULLFROG HEMOGRAM UNDER MANAGEMENT STRESS

    Directory of Open Access Journals (Sweden)

    Patrícia Coelho Teixeira

    2015-04-01

    Full Text Available Stress is one of the major obstacles in frog culture and can be caused by factors such as inappropriate farming systems; inadequate management among other situations. The objective of the present study was to assess the hemogram, erythrogram and leukogram of bullfrogs (L. catesbeianus when exposed to stress caused by different types of management: density and handling (manipulation, developed in the laboratory and repeated in the field for the appropriate comparisons in a experimental period of 30 days. The density experiment was conducted with four treatments: 70 animals m-2 (D70; 100 animals m-2 (D100, Control; 150 animals m-2 (D150 and 200 animals m-2 (D200, with 10, 14, 21 and 28 animals/box in the laboratory, respectively. Each treatment was performed with three simultaneous replicates. The handling experiment was conducted with three treatments: Treatment Without Handling (WH; Treatment with Partial Handling (PH every 15 days and Treatment with Total Handling (TH every 15 days. Each treatment was performed with four simultaneous replications. The methodology of the blood analysis followed international recommendations. In the present study we could observe that the animals of the field experiment did not reflect the same stress response observed in the laboratory in both experiment, which demonstrated the plasticity of these animals.

  6. Patterns of Cranial Development in Larval Rana macrocnemis: Chondrocranial Size and Shape Relationship With Pelophylax bedriagae (Anura: Ranidae).

    Science.gov (United States)

    Yildirim, Elıf; Kaya, Uğur

    2016-06-01

    Notwithstanding the abundance of amphibians, there are few descriptions about ranid cranial development. Herein, larval chondrocranial development of Uludağ frog, Rana macrocnemis (Boulenger, 1885), is described on cleared and double-stained specimens. Descriptions are related with the ontogeny of the chondrocranium and osteogenesis of the cranial skeleton. The larval chondrocranial development of R. macrocnemis is compared to those of Rana and Pelophylax larvae (Pelophylax bedriagae, Rana pipiens, R. palustris, R. sphenocephala, R. catesbeiana, R. clamitans and R. sylvatica). In R. macrocnemis, the first bones to ossify are the parasphenoid and exoccipital (Stage 33), followed by the frontoparietal and prootic (stages 35 and 40, respectively). The major reconstruction of the chondrocranium begins at Stage 41. The ossification sequence of R. macrocnemis is distinguished from other ranids. Adult cranial osteology of R. macrocnemis is compared to that of P. bedriagae. Osteologically, R. macrocnemis is different from P. bedriagae by the shape and size of the vomer and number of teeth. Additionally, geometric morphometric methods are used to analyze chondrocranial size and shape changes of ranid larva of R. macrocnemis and P. bedriagae. Anat Rec, 299:711-721, 2016. © 2016 Wiley Periodicals, Inc. PMID:26950267

  7. Frog community responses to recent American bullfrog invasions

    Institute of Scientific and Technical Information of China (English)

    Yiming LI; Zhunwei KE; Yihua WANG; Tim M. BLACKBURN

    2011-01-01

    Native species may decline quickly when confronted with an exotic species to which they are not adapted. The extent of decline may depend on the abundance of an invader and the length of time since it first arrived in the community (residence time), and the interaction between these two variables. We tested these effects using data on the effects of American bullfrog Lithobates catesbeianus invasion on native frog communities in 65 permanent lentic waters on islands in the Zhoushan Archipelago, China. We examined variation in native frog abundance and species richness in relation to features of the American bullfrog invasion, habitat disturbance, characteristics of the water body and fish communities and the presence of red swamp crayfish.Bullfrog invaded sites had lower native frog density and species richness, higher submerged vegetation cover and greater frequency of repairs to the water body than did non-invaded sites. The minimum adequate general linear mixed models showed that both native frog density and species richness were negatively related to post-metamorphosis bullfrog density, and that native frog species richness was also positively related to the vegetation cover. There was no effect on either native frog density or species richness of residence time or its interaction with bullfrog density, or of the abundance of bullfrog tadpoles. The results suggested that post-metamorphosis bullfrogs had impacts on native frog communities in the islands, and that the extents of these impacts are proportional to post-metamorphosis bullfrog density.

  8. A New Kind of Biomaterials-Bullfrog Skin Collagen

    Institute of Scientific and Technical Information of China (English)

    He LI; Bai Ling LIU; Hua Lin CHEN; Li Zhen GAO

    2003-01-01

    Pepsin-soluble collagen was prepared from bullfrog skin and partially characterized. This study revealed interesting differences, such as molecular weight, amino acid composition, denaturation temperature (Td), in the frog skin collagen when compared to the known vertebrate collagens. This study gives hints that bullfrog skin can be a potential, safe alternative source of collagen from cattle for use in various fields.

  9. DIFERENCIJALNA DIJAGNOZA KRONIČNIH RANA

    OpenAIRE

    Šitum, Mirna; KOLIĆ, MAJA

    2014-01-01

    Rana je prekid anatomskog i funkcionalnog kontinuiteta tkiva, a s obzirom na tijek cijeljenja rane dijelimo na akutne i kronične. kronična rana je rana koja unatoč standardnom medicinskom postupku ne cijeli očekivanom dinamikom, odnosno u užem smislu rana koja ne cijeli unutar 6 tjedana. kronične rane mogu biti tipične i atipične. u tipične rane ubrajaju se ishemijske, neurotrofičke i hipostatske rane te dva posebna entiteta: dekubitus i dijabetičko stopalo. kronične rane na potkoljenicama su...

  10. Uniaxial compression test series on Bullfrog Tuff

    International Nuclear Information System (INIS)

    Nineteen uniaxial compressive experiments were performed on samples of the Bullfrog Member of the Crater Flat Tuff, obtained from drillhole USW-G1 at Yucca Mountain on the Nevada Test Site. The water saturated samples were deformed at a nominal strain rate of 10-5 sec-1, atmospheric pressure and room temperature. Resultant unconfined compressive strengths, axial strains to failure, Young's moduli and Poisson's ratios ranged from 4.63 to 153. MPa, .0028 to .0058, 2.03 to 28.9 GPa and .08 to .16, respectively

  11. Ionic currents in single isolated bullfrog atrial cells

    OpenAIRE

    1983-01-01

    Enzymatic dispersion has been used to yield single cells from segments of bullfrog atrium. Previous data (Hume and Giles, 1981) have shown that these individual cells are quiescent and have normal resting potentials and action potentials. The minimum DC space constant is approximately 920 microns. The major goals of the present study were: (a) to develop and refine techniques for making quantitative measurements of the transmembrane ionic currents, and (b) to identify the individual component...

  12. Antibiogram and heavy metal tolerance of bullfrog bacteria in Malaysia

    OpenAIRE

    Najiah, M.; L.W. Tee

    2011-01-01

    Bacterial isolates from 30 farmed bullfrogs (Lithobates catesbeianus) weighing 500-600 g at Johore, Malaysia with external clinical signs of ulcer, red leg and torticollis were tested for their antibiograms and heavy metal tolerance patterns. A total of 17 bacterial species with 77 strains were successfully isolated and assigned to 21 antibiotics and 4 types of heavy metal (Hg2+, Cr6+, Cd2+, Cu2+). Results revealed that bacteria were resistant against lincomycin (92%), oleandomycin (72.7%) an...

  13. Antibiogram and heavy metal tolerance of bullfrog bacteria in Malaysia

    Directory of Open Access Journals (Sweden)

    M. Najiah

    2011-10-01

    Full Text Available Bacterial isolates from 30 farmed bullfrogs (Lithobates catesbeianus weighing 500-600 g at Johore, Malaysia with external clinical signs of ulcer, red leg and torticollis were tested for their antibiograms and heavy metal tolerance patterns. A total of 17 bacterial species with 77 strains were successfully isolated and assigned to 21 antibiotics and 4 types of heavy metal (Hg2+, Cr6+, Cd2+, Cu2+. Results revealed that bacteria were resistant against lincomycin (92%, oleandomycin (72.7% and furazolidone (71.4% while being susceptible to chloramphenicol and florfenicol at 97.4%. The multiple antibiotic resistance (MAR index for C. freundii, E. coli and M. morganii was high with the value up to 0.71. Bacterial strains were found to exhibit 100 % resistance to chromium and mercury. High correlation of resistance against both antibiotics and heavy metals was found (71.4 to 100% between bullfrog bacteria isolates, except bacteria that were resistant to kanamycin showed only 25% resistance against Cu2+. Based on the results in this study, bacterial pathogens of bullfrog culture in Johore, Malaysia, were highly resistant to both antibiotics and heavy metals.

  14. Comparative transduction mechanisms of hair cells in the bullfrog utriculus. 1: Responses to intracellular current

    Science.gov (United States)

    Baird, Richard A.

    1994-01-01

    Hair cells in the bullfrog sacculus are specifically adapted to sense small-amplitude, high-frequency linear accelerations. These hair cells display many properties that are undesirable or inappropriate for hair cells that must provide static gravity sensitivity. This study resulted in part due to an interest in seeing how the transduction mechanisms of hair cells in a gravity-sensing otolith endorgan would differ from those in the bullfrog sacculus. The bullfrog utriculus is an appropriate model for these studies, because its structure is representative of higher vertebrates in general and its function as a sensor of static gravity and dynamic linear acceleration is well known. Hair cells in the bullfrog utriculus, classifiable as Type 2 by cell body and synapse morphology, differ markedly in hair bundle morphology from those in the bullfrog sacculus. Moreover, the hair bundle morphologies of utricular hair cells, unlike those in the sacculus, differ in different membrane regions.

  15. Histological Study on Reproductive Organ of Rana Temporaria Chensinesis David

    Institute of Scientific and Technical Information of China (English)

    HUANG He; TIAN Yaguang; NING Fangyong; BAI Xiujuan; ZHANG Guixue

    2006-01-01

    The experiment was designed to study the histology of reproductive organ of Rana temporaria chensinesis David in reproductive season and dereproductive season, The results displayed that the sexual gland weight and oviduct weight of the Rana temporaria chensinesis David were significantly different between reproductive season and dereproductive season.

  16. Stretch-activated cation channel from larval bullfrog skin

    OpenAIRE

    Hillyard, Stanley D.; Willumsen, Niels J.; Marrero, Mario B.

    2010-01-01

    Cell-attached patches from isolated epithelial cells from larval bullfrog skin revealed a cation channel that was activated by applying suction (−1 kPa to −4.5 kPa) to the pipette. Activation was characterized by an initial large current spike that rapidly attenuated to a stable value and showed a variable pattern of opening and closing with continuing suction. Current–voltage plots demonstrated linear or inward rectification and single channel conductances of 44–56 pS with NaCl or KCl Ringer...

  17. DEFINICIJA I PODJELA ATIPIČNIH RANA

    OpenAIRE

    Šitum, Mirna; KOLIĆ, MAJA

    2013-01-01

    Prema definiciji rana je prekid anatomskog i funkcionalnog kontinuiteta tkiva, a s obzirom na tijek cijeljenja rane mogu biti akutne i kronične. Kronične rane su one koje ne zarastaju unutar predviđenog razdoblja u korelaciji s etiologijom i lokalizacijom rane, a u najkraćem razdoblju od 6 tjedana. Kronične rane mogu biti tipične i atipične. u tipične rane ubrajaju se ishemijske rane, neuropatski ulkus, venski ulkus te dva posebna entiteta: dekubitus i dijabetičko stopalo. Kronične rane na po...

  18. Presa de Campillo de las Ranas

    OpenAIRE

    Castro Canabal, Pablo

    2012-01-01

    La construcción de la presa de Campillo de las Ranas se enmarca dentro del plan hidrológico del Tajo, por el que se pretende aumentar las garantías de suministro sobre todo a la ciudades y núcleos poblacionales de la cuenca alta del mismo, además de para poder garantizar que el caudal ecológico en épocas de sequia en los puntos que actualmente están registrando niveles inferiores a los requeridos en dichos periodos de estiaje y específicamente tiene su objeto en el abastecimiento del in...

  19. Distribution of the amphibian pathogen Batrachochytrium dendrobatidis in the Pacific Northwestern USA

    Science.gov (United States)

    Pearl, Christopher A.; Bull, E.L.; Green, D.E.; Bowerman, Jay; Adams, Michael J.; Hyatt, A.; Wente, W.

    2007-01-01

    Chytridiomycosis (infection by the fungus Batrachochytrium dendrobatidis) has been associated with amphibian declines in at least four continents. We report results of disease screens from 210 pond-breeding amphibians from 37 field sites in Oregon and Washington. We detected B. dendrobatidis on 28% of sampled amphibians, and we found a?Y 1 detection of B. dendrobatidis from 43% of sites. Four of seven species tested positive for B. dendrobatidis, including the Northern Red-Legged Frog (Rana aurora), Columbia Spotted Frog (Rana luteiventris), and Oregon Spotted Frog (Rana pretiosa). We also detected B. dendrobatidis in nonnative American Bullfrogs (Rana catesbeiana) from six sites in western and central Oregon. Our study and other recently published findings suggest that B. dendrobatidis has few geographic and host taxa limitations among North American anurans. Further research on virulence, transmissibility, persistence, and interactions with other stressors is needed to assess the potential impact of B. dendrobatidis on Pacific Northwestern amphibians.

  20. Stretch-activated cation channel from larval bullfrog skin

    DEFF Research Database (Denmark)

    Hillyard, Stanley D; Willumsen, Niels J; Marrero, Mario B

    2010-01-01

    Cell-attached patches from isolated epithelial cells from larval bullfrog skin revealed a cation channel that was activated by applying suction (-1 kPa to -4.5 kPa) to the pipette. Activation was characterized by an initial large current spike that rapidly attenuated to a stable value and showed a...... markedly reduced with N-methyl-D-glucamide (NMDG)-Cl Ringer's solution in the pipette. Neither amiloride nor ATP, which are known to stimulate an apical cation channel in Ussing chamber preparations of larval frog skin, produced channel activation nor did these compounds affect the response to suction....... Stretch activation was not affected by varying the pipette concentrations of Ca(2+) between 0 mmol l(-1) and 4 mmol l(-1) or by varying pH between 6.8 and 8.0. However, conductance was reduced with 4 mmol l(-1) Ca(2+). Western blot analysis of membrane homogenates from larval bullfrog and larval toad skin...

  1. The identity of Rana lutea Molina, 1782 (Amphibia, Anura).

    Science.gov (United States)

    Ferraro, Daiana P; Lavilla, Esteban O

    2013-01-01

    Rana lutea is one of the two anuran species described in 1782 by the Chilean born priest and naturalist Juan Ignacio Molina, and its nomenclatural history is confusing. After a detailed revision of the pertinent literature, we demonstrate that Bufo thaul Schneider, 1799, is a junior objective synonym of Rana lutea Molina, 1782, but based on the usage of both nomina, we revert the precedence and consider Rana lutea Molina, 1782 as a nomen oblitum whereas Bufo thaul Schneider, 1799 is a nomen protectum. Thus, the authorship of the species currently known as Pleurodema thaul (Lesson, 1826) changes to Pleurodema thaul (Schneider, 1799). PMID:24614468

  2. Agro-climatic Division of Rana chensinensis in Fushun

    OpenAIRE

    Li, Liang; Zhang, Yu

    2012-01-01

    Based on data collected by 3 basic weather stations in Fushun City and 47 automatic weather stations in the whole region, we selected indexes suitable for agro-climatic division of Rana Chensinensis, and carried out a study on agro-climatic division of Rana Chensinensis in this region. Annual active accumulated temperature ≥10℃ and precipitation during April and September are used as basic calculation factors, and we use climatic aridity to make climatic division of Rana Chensinensis in F...

  3. Suplementação com vitamina C e E sobre o desenvolvimento e sobrevivência de girinos de rã-touro (Rana catesbeiana Shaw, 1802)

    OpenAIRE

    Stéfani Marta Verardino De; Marcantonio Adriana Sacioto; Martins Maurício Laterça

    2001-01-01

    O presente trabalho teve como objetivo avaliar os efeitos da suplementação de vitamina C e E sobre o desenvolvimento e sobrevivência de girinos de rã-touro. Os animais receberam 50, 250 e 500mg de vitamina C ou E/kg de ração, distribuídos segundo delineamento inteiramente casualizado com 3 repetições cada. Na dieta controle, não foram adicionadas vitaminas. Os girinos suplementados com vitamina C ou E não apresentaram diferença significativa no crescimento, comparados ao controle. Não obstant...

  4. Status of bullfrogs and northern leopard frogs at Fish Springs National Wildlife Refuge, Juab County, Utah

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document describes aspects of the ecology and natural history of bullfrogs introduced to Fish Springs National Wildlife Refuge. The purpose of this study was...

  5. Final Critical Habitat for Oregon Spotted Frog (Rana pretiosa)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify, in general, the areas of FINAL critical habitat for Rana pretiosa (Oregon Spotted Frog). Maps published in the Federal Register 2016.

  6. Trophic ecology and microhabitat utilization by the Bufo gargarizans, Rana guentheri, and Rana limnocharis in southwestern China

    OpenAIRE

    Tonglei Yu; Yanshu Guo

    2012-01-01

    We studied the trophic ecology and microhabitat use of the Asiatic toad, Bufo gargarizans Cantor, 1842; Guentheri frog, Rana guentheri (Boulenger, 1882); and the Ricefield frog, Rana limnocharis (Boie, 1834). These three species are common around Nanchong City, in southwestern China, where they live in the same habitat before hibernation. The main objective of this study was to analyze the diets and patterns of coexistence relative to the microhabitat of each species. In the Asiatic toad, bas...

  7. Bullfrog (Lithobates catesbeianus farming system: water quality and environmental changes

    Directory of Open Access Journals (Sweden)

    Cacilda Thais Janson Mercante

    2014-03-01

    Full Text Available INTRODUCTION: Frog farming, if not well managed, may cause environmental damages. The use of antibiotics, the organic discharge and the introduction of exotic species can disseminate risks such as eutrophication, changes in the water quality and organic pollution, factors that affect the human consumption. AIM: Evaluating the water quality of a bullfrog farming system, discussing their relations to production and the environment based on the current legislation. METHODS: Sampling was performed on a monthly basis from November 2006 to March 2007 during growth and fattening phases of bullfrog (Lithobates catesbeianus. Sample sites were distributed according to the water flow: upstream from the mixing zone, affluent (supply water, bay, effluent, mixing zone and downstream from the mixing zone. In the field, pH, electrical conductivity, dissolved oxygen, temperature and turbidity were measured. In laboratory, nitrogen, phosphorus and chlorophyll a concentrations were analyzed. RESULTS: The concentration of nutrients was determiner for water quality in the bay and its effluent. According to the current legislation, the effluent exceeded the limits for total phosphorus (> 0.030 mg L-1 and total nitrogen (> 1.27 mg L-1. Other variables presented acceptable values in light of the current laws. CONCLUSION: The high values of nutrients and other factors such as conductivity and turbidity are proportional to the animal growth due to the inadequate management practices evidenced by feed conversion rate. The following management options are proposed: maintaining the flow and decreased density of animals; maintaining the flow and density storage with adequate control of the food supply.

  8. L'introduction d'espèces allochtones de grenouilles vertes en France, deux problèmes différents : celui de R. Catesbeiana et celui des taxons non présents du complexe Esculenta

    Directory of Open Access Journals (Sweden)

    NEVEU A.

    1997-01-01

    Full Text Available Depuis quelques années, la grenouille taureau (Rana catesbeiana est signalée en France dans une zone limitée de gravières près de Bordeaux. Elle est aussi présente depuis peu aux Pays-Bas et, dans les deux cas, la reproduction est effective. Cette espèce existe déjà en Europe depuis les années 30, à la suite d'introductions volontaires en Italie, sans pour cela avoir été signalée dans la partie ouest. La grenouille taureau est la plus grande des espèces nord-américaines et est considérée comme un prédateur éclectique. De ce fait, elle peut présenter un danger pour d'autres animaux, en particulier les grenouilles autochtones. Mais aucune donnée ne permet d'estimer cet éventuel impact en France et les données de la littérature ont souvent surestimé ce dernier. Par précaution, des mesures pourraient être prises pour réduire les populations actuelles présentes dans une aire pour le moment limitée. Les importations de grenouilles vivantes pour la consommation humaine, surtout à partir des pays du sud de l'Europe, sont l'occasion d'introductions de nouveaux taxons. Mais ces grenouilles font partie du même complexe et sont proches sur le plan morphologique, biologique et écologique. Les risques potentiels pour les populations locales sont les introductions de gènes, mais en ce qui concerne un éventuel avantage compétitif aucune donnée ne permet de conclure.

  9. Immunostimulatory Activity of Protein Hydrolysate from Oviductus Ranae on Macrophage In Vitro

    OpenAIRE

    2014-01-01

    Oviductus Ranae is the dry oviduct of Rana chensinensis, which is also called R. chensinensis oil. Oviductus Ranae is a valuable Chinese crude drug and is recorded in the Pharmacopoeia of the People's Republic of China. The aim of this study was to investigate the immunostimulatory activity of protein hydrolysate of Oviductus Ranae (ORPH) and to assess its possible mechanism. Immunomodulatory activity of ORPH was examined in murine macrophage RAW 264.7 cells. The effect of ORPH on the phagocy...

  10. Optimization of Extraction Conditions on the Yield of Rana Chensinensis Egg Oil by Statistical Experimental Designs

    OpenAIRE

    Wenxuan Zhao; Fuguang Zhao; Guang Chen

    2015-01-01

    Rana chensinensis egg oil is extracted from Rana chensinensis. The important variables (extraction temperature, extraction time and the ratio of oviductus ranae egg oil and extraction solvent) were optimized by Box-Behnken central composite design under response surface methodology. The statistical analysis showed that the optimum extraction conditions (extraction temperature 60.62C, extraction time 3.16 h and the ratio of oviductus ranae egg oil and extraction solvent 8.91.) led to a maximu...

  11. American Bullfrogs (Lithobates catesbeianus) Resist Infection by Multiple Isolates of Batrachochytrium dendrobatidis, Including One Implicated in Wild Mass Mortality

    OpenAIRE

    Eskew, EA; Worth, SJ; Foley, JE; Todd, BD

    2015-01-01

    © 2015, International Association for Ecology and Health. The emerging amphibian disease chytridiomycosis varies in severity depending on host species. Within species, disease susceptibility can also be influenced by pathogen variation and environmental factors. Here, we report on experimental exposures of American bullfrogs (Lithobates catesbeianus) to three different isolates of Batrachochytrium dendrobatidis (Bd), including one implicated in causing mass mortality of wild American bullfrog...

  12. Reproductive phenology of the American Bullfrog in subtropical Brazil: photoperiod as a main determinant of seasonal activity.

    Science.gov (United States)

    Medeiros, Camila I; Both, Camila; Kaefer, Igor L; Cechin, Sonia Z

    2016-07-11

    The North American bullfrog Lithobates catesbeianus continues to invade ecosystems worldwide, potentially causing population declines and even extinctions. Within its native distribution, bullfrogs show prolonged reproductive seasons and high fertility. However, data on breeding biology of bullfrogs ex-situ in invaded localities mainly comes from anecdotal reports. Understanding how invasive species are adjusting their life histories to new colonized environments is important for conservation purposes. Here we describe temporal and spatial abundance, calling activity, spawning and tadpole distribution of bullfrogs in southern Brazil. Eighteen samplings occurred during one year. The abundance of individuals was positively related to longer photoperiods and higher temperatures. Reproductive activity was also positively associated with longer photoperiods. Calling sites, spawning and tadpoles were associated with microhabitats presenting hydrophytes, which may provide shelter and thermal stability to bullfrogs. The reproductive seasonal activity of bullfrogs can be highly variable across its growing geographical range, but in subtropical Brazil it is associated with photoperiod, a highly predictable abiotic determinant. In our study area, bullfrogs presented a breeding season twice as long as that observed in some native localities. We suggest that management strategies directed to bullfrog populations must consider the habitat structures and seasonal regimes determined by each invaded environment. PMID:27411069

  13. Climate change and American Bullfrog invasion: what could we expect in South America?

    Directory of Open Access Journals (Sweden)

    Javier Nori

    Full Text Available BACKGROUND: Biological invasion and climate change pose challenges to biodiversity conservation in the 21(st century. Invasive species modify ecosystem structure and functioning and climatic changes are likely to produce invasive species' range shifts pushing some populations into protected areas. The American Bullfrog (Lithobates catesbeianus is one of the hundred worst invasive species in the world. Native from the southeast of USA, it has colonized more than 75% of South America where it has been reported as a highly effective predator, competitor and vector of amphibian diseases. METHODOLOGY/PRINCIPAL FINDINGS: We modeled the potential distribution of the bullfrog in its native range based on different climate models and green-house gases emission scenarios, and projected the results onto South America for the years of 2050 and 2080. We also overlaid projected models onto the South American network of protected areas. Our results indicate a slight decrease in potential suitable area for bullfrog invasion, although protected areas will become more climatically suitable. Therefore, invasion of these sites is forecasted. CONCLUSION/SIGNIFICANCE: We provide new evidence supporting the vulnerability of the Atlantic Forest Biodiversity Hotspot to bullfrog invasion and call attention to optimal future climatic conditions of the Andean-Patagonian forest, eastern Paraguay, and northwestern Bolivia, where invasive populations have not been found yet. We recommend several management and policy strategies to control bullfrog invasion and argue that these would be possible if based on appropriate articulation among government agencies, NGOs, research institutions and civil society.

  14. Diet and Prey Selection of the Invasive American Bullfrog (Lithobates catesbeianus) in Southwestern China

    Institute of Scientific and Technical Information of China (English)

    Xuan LIU; Yu LUO; Jiaxin CHEN; Yisong GUO; Changming BAI; Yiming LI

    2015-01-01

    Invasive predators have been widely regarded as one of the principle drivers of the global decline of amphibians, which are among the most threatened vertebrate taxon on Earth. The American bullfrog (Lithobates catesbeianus) is identiifed as one of the most successful vertebrate invaders and has caused the decline or extinction of some native amphibians in many regions and countries including China. Based on ifeld surveys and stomach content analyses, we examined the diet composition of the invasive bullfrog for the ifrst time in two invaded populations in Yunnan Province, southwestern China, a region of global conservation priority, during the breeding season from 2008 to 2014. Additionally, we conducted the first quantitative study on the prey selection of this global invader among their invaded ranges after controlling for the local anuran assemblage and other aquatic preys in the environment. Our results showed that the range of food items in the stomachs of bullfrogs spanned more than 30 species belonging to ten taxonomic classes. Both of post-metamorphosis individuals and juveniles preyed upon native frogs, independent of the bullfrog’s body size and mouth width. Importantly, Jacobs’ selection index showed a bullfrog preference for the Yunnan pond frog (Babina pleuraden), one native endemic anuran with population decline, in terms of both food volume and occurrence. We therefore provided direct evidence on the predation impact of the invasive bullfrog on an endemic anuran and urged further efforts to prevent the dispersal of this invader into more fragile habitats to reduce their negative impacts on native amphibians.

  15. Cardiac adaptations of bullfrog tadpoles in response to chytrid infection.

    Science.gov (United States)

    Salla, Raquel Fernanda; Gamero, Fernando Urban; Ribeiro, Larissa Rodrigues; Rizzi, Gisele Miglioranza; Medico, Samuel Espinosa Dal; Rissoli, Rafael Zanelli; Vieira, Conrado Augusto; Silva-Zacarin, Elaine Cristina Mathias; Leite, Domingos Silva; Abdalla, Fábio Camargo; Toledo, Luis Felipe; Costa, Monica Jones

    2015-08-01

    The chytrid fungus Batrachochytrium dendrobatidis (Bd) can result in heart failure in Bd-susceptible species. Since Bd infection generally does not cause mortality in North American bullfrogs, the aim of this work was to verify whether this species presents any cardiac adaptation that could improve the tolerance to the fungus. Thus, we analyzed tadpoles' activity level, relative ventricular mass, ventricle morphology, in loco heart frequency, and in vitro cardiac function. The results indicate that infected animals present an increase in both ventricular relative mass and in myofibrils' incidence, which accompanied the increase in myocytes' diameter. Such morphological alterations enabled an increase in the in vitro twitch force that, in vivo, would result in elevation of the cardiac stroke volume. This response requires much less energy expenditure than an elevation in heart frequency, but still enables the heart to pump a higher volume of blood per minute (i.e., an increase in cardiac output). As a consequence, the energy saved in the regulation of the cardiac function of Bd-infected tadpoles can be employed in other homeostatic adjustments to avoid the lethal effect of the fungus. Whether other species present this ability, and to what extent, remains uncertain, but such possible interspecific variability might explain different mortality rates among different species of Bd-infected amphibians. PMID:26055358

  16. Rana dalmatina-ren (Amphibia, Ranidae) presentziari buruz Nafarroan.

    OpenAIRE

    ARRAIAGO, M.J., BEA, A.

    1984-01-01

    Se han localizado una puesta y varias larvas de Rana dalmatina en Arbizu (Navarra), U.T.M. 30TWN75. Se describe el hábitat donde se localizó la puesta. Esta especie se incluye definitivamente en la   fauna navarra.

  17. Asymmetric [14C]albumin transport across bullfrog alveolar epithelium

    International Nuclear Information System (INIS)

    Bullfrog lungs were prepared as planar sheets and bathed with Ringer solution in Ussing chambers. In the presence of a constant electrical gradient (20, 0, or -20 mV) across the tissue, 14C-labeled bovine serum albumin or inulin was instilled into the upstream reservoir and the rate of appearance of the tracer in the downstream reservoir was monitored. Two lungs from the same animal were used to determine any directional difference in tracer fluxes. An apparent permeability coefficient was estimated from a relationship between normalized downstream radioactivities and time. Results showed that the apparent permeability of albumin in the alveolar to pleural direction across the alveolar epithelial barrier is 2.3 X 10(-7) cm/s, significantly greater (P less than 0.0005) than that in the pleural to alveolar direction (5.3 X 10(-8) cm/s) when the tissue was short circuited. Permeability of inulin, on the other hand, did not show any directional dependence and averaged 3.1 X 10(-8) cm/s in both directions. There was no effect on radiotracer fluxes permeabilities of different electrical gradients across the tissue. Gel electrophoretograms and corresponding radiochromatograms suggest that the large and asymmetric isotope fluxes are not primarily due to digestion or degradation of labeled molecules. Inulin appears to traverse the alveolar epithelial barrier by simple diffusion through hydrated paracellular pathways. On the other hand, [14C]albumin crosses the alveolar epithelium more rapidly than would be expected by simple diffusion. These asymmetric and large tracer fluxes suggest that a specialized mechanism is present in alveolar epithelium that may be capable of helping to remove albumin from the alveolar space

  18. Is hypoxia a stressor to American bullfrog tadpoles?

    Directory of Open Access Journals (Sweden)

    Patricia C. Teixeira

    2014-04-01

    Full Text Available The aim of this study was to evaluate alterations to the physiological profile of cortisol in pro-metamorphose phase tadpoles of Lithobates catesbeianus exposed to hypoxia stressor in a capture experiment and in a crowding experiment. The capture study was performed by the treatments: stress due to individual capture with a hand net, stress due to batch capture with a hand net and stress due to capture by emptying. Three simultaneous replicates was done witch 12 animals were sampled (6 normoxia - immediately blood collection and 6 hypoxia - blood collection after 15 min of air exposition in two collection times with 5 days by intervals. The crowding study was performed by the treatments 1 tadpole L-1, 5 tadpoles L-1 and 10 tadpoles L-1. Three simultaneous replicates was done witch 8 animals (4 normoxia and 4 hypoxia were sampled in the zero moment (ZM - blood collection before the experiment, 6 animals/treatment (3 normoxia and 3 hypoxia to 4 and 8 days and 18 animals/treatment (9 normoxia and 9 hypoxia to 12 days. The average values to plasmatic cortisol varying from 1.7 to 5.1ng mL-1 (capture study and 1.0 to 4.2ng mL-1 (crowding study. It concludes that the biomarker tested (cortisol showed no alterations front of the stressor used. Alternatively, a larger response pattern to these stimuli may have been expressed in another level of an unmeasured hormone (corticosterone. And the bullfrog has great ability to adapt to different management compared to other aquatic organisms, which demonstrates the plasticity of these animals.

  19. American Bullfrogs (Lithobates catesbeianus) Resist Infection by Multiple Isolates of Batrachochytrium dendrobatidis, Including One Implicated in Wild Mass Mortality.

    Science.gov (United States)

    Eskew, Evan A; Worth, S Joy; Foley, Janet E; Todd, Brian D

    2015-09-01

    The emerging amphibian disease chytridiomycosis varies in severity depending on host species. Within species, disease susceptibility can also be influenced by pathogen variation and environmental factors. Here, we report on experimental exposures of American bullfrogs (Lithobates catesbeianus) to three different isolates of Batrachochytrium dendrobatidis (Bd), including one implicated in causing mass mortality of wild American bullfrogs. Exposed frogs showed low infection prevalence, relatively low infection load, and lack of clinical disease. Our results suggest that environmental cofactors are likely important contributors to Bd-associated American bullfrog mortality and that this species both resists and tolerates Bd infection. PMID:26065669

  20. Basolateral Cl- channels in the larval bullfrog skin epithelium

    DEFF Research Database (Denmark)

    Hillyard, Stanley D.; Rios, K.; Larsen, Erik Hviid

    2002-01-01

    The addition of 150 U/ml nystatin to the mucosal surface of isolated skin from larval bullfrogs increases apical membrane permeability and allows a voltage clamp to be applied to the basolateral membrane. With identical Ringer's solutions bathing either side of the tissue the short-circuit curren...

  1. Control of lung ventilation following overwintering conditions in bullfrogs, Lithobates catesbeianus.

    Science.gov (United States)

    Santin, Joseph M; Hartzler, Lynn K

    2016-07-01

    Ranid frogs in northern latitudes survive winter at cold temperatures in aquatic habitats often completely covered by ice. Cold-submerged frogs survive aerobically for several months relying exclusively on cutaneous gas exchange while maintaining temperature-specific acid-base balance. Depending on the overwintering hibernaculum, frogs in northern latitudes could spend several months without access to air, the need to breathe or the chemosensory drive to use neuromuscular processes that regulate and enable pulmonary ventilation. Therefore, we performed experiments to determine whether aspects of the respiratory control system of bullfrogs, Lithobates catesbeianus, are maintained or suppressed following minimal use of air breathing in overwintering environments. Based on the necessity for control of lung ventilation in early spring, we hypothesized that critical components of the respiratory control system of bullfrogs would be functional following simulated overwintering. We found that bullfrogs recently removed from simulated overwintering environments exhibited similar resting ventilation when assessed at 24°C compared with warm-acclimated control bullfrogs. Additionally, ventilation met resting metabolic and, presumably, acid-base regulation requirements, indicating preservation of basal respiratory function despite prolonged disuse in the cold. Recently emerged bullfrogs underwent similar increases in ventilation during acute oxygen lack (aerial hypoxia) compared with warm-acclimated frogs; however, CO2-related hyperventilation was significantly blunted following overwintering. Overcoming challenges to gas exchange during overwintering have garnered attention in ectothermic vertebrates, but this study uncovers robust and labile aspects of the respiratory control system at a time point correlating with early spring following minimal to no use of lung breathing in cold-aquatic overwintering habitats. PMID:27091862

  2. Solitary Hair Cells Are Distributed Throughout the Extramacular Epithelium in the Bullfrog's Saccule

    OpenAIRE

    Gale, Jonathan E.; Meyers, Jason R.; Corwin, Jeffrey T.

    2000-01-01

    The frog inner ear contains eight sensory organs that provide sensitivities to auditory, vestibular, and ground-borne vibrational stimuli. The saccule in bullfrogs is responsible for detecting ground- and air-borne vibrations and is used for studies of hair cell physiology, development, and regeneration. Based on hair bundle morphology, a number of hair cell types have been defined in this organ. Using immunocytochemistry, vital labeling, and electron microscopy, we have characterized a new h...

  3. Genetic reconstruction of a bullfrog invasion to elucidate vectors of introduction and secondary spread

    Science.gov (United States)

    Kamath, Pauline L.; Sepulveda, Adam; Layhee, Megan J.

    2016-01-01

    Reconstructing historical colonization pathways of an invasive species is critical for uncovering factors that determine invasion success and for designing management strategies. The American bullfrog (Lithobates catesbeianus) is endemic to eastern North America, but now has a global distribution and is considered to be one of the worst invaders in the world. In Montana, several introduced populations have been reported, but little is known of their sources and vectors of introduction and secondary spread. We evaluated the genetic composition of introduced populations at local (Yellowstone River floodplain) and regional (Montana and Wyoming) scales in contrast to native range populations. Our objectives were to (1) estimate the number of introductions, (2) identify probable native sources, (3) evaluate genetic variation relative to sources, and (4) characterize properties of local- and regional-scale spread. We sequenced 937 bp of the mitochondrial cytochrome b locus in 395 tadpoles collected along 100 km of the Yellowstone River, from three additional sites in MT and a proximate site in WY. Pairwise ΦST revealed high divergence among nonnative populations, suggesting at least four independent introductions into MT from diverse sources. Three cyt b haplotypes were identical to native haplotypes distributed across the Midwest and Great Lakes regions, and AMOVA confirmed the western native region as a likely source. While haplotype (Hd = 0.69) and nucleotide diversity (π = 0.005) were low in introduced bullfrogs, the levels of diversity did not differ significantly from source populations. In the Yellowstone, two identified haplotypes implied few introduction vectors and a significant relationship between genetic and river distance was found. Evidence for multiple invasions and lack of subsequent regional spread emphasizes the importance of enforcing legislation prohibiting bullfrog importation and the need for continuing public education to prevent

  4. Morphometric growth characteristics and body composition of bullfrog tadpoles in captivity

    Directory of Open Access Journals (Sweden)

    Cleber Menegasso Mansano

    2014-10-01

    Full Text Available Feed management needs to be improved in frog farming to reduce the indirect effects of inadequate feeding and, consequently, to increase growth rates and nutrient deposition, obtaining better quality animals. The objective of this study was to establish morphometric growth curves for bullfrog tadpoles (Lithobates catesbeianus and to determine nutrient deposition in the carcass. A total of 6,480 bullfrogs (Gosner stage 25 received an experimental diet (26.23% digestible protein and 32.68% crude protein and a commercial diet (37.92% crude protein ad libitum. A Gompertz model was used to describe the growth curve. Tadpoles fed the experimental diet presented higher final protein deposition. In addition, the sigmoidal curve was much more homogenous, indicating a more constant daily protein deposition rate. The Gompertz model provided an excellent fit of the data to describe the morphometric growth curve and carcass nutrient deposition of bullfrog tadpoles, showing that animals fed the experimental diet presented a better growth rate and nutrient deposition.

  5. El regimen alimentario de la rana verde de África del norte, Rana saharica - The food mode of north African green frog, Rana saharica - Le regime alimentaire de la grenouille verte d’afrique du nord, rana saharica

    Directory of Open Access Journals (Sweden)

    Meher BELLAKHAL

    2010-07-01

    Full Text Available ResumenPara la determinación del régimen alimentario de la rana verde de Áfricadel norte Rana (Pelophylax saharica, se recogieron 360 especímenes apartir de 2 lagos de la región Septentrional de Túnez desde el mes de abrilhasta el mes de septiembre. Constatamos que las presas pertenecenprincipalmente a los artrópodos, en particular los coleópteros (38.29% ylos dípteros (23.47%. Más de vez en cuando, algunos renacuajos yjuveniles de la misma especie así como otras presas acuáticas, se hantambién descubierto en el contenido estomacal. El número de presa máselevado (231 se observó en el mes de junio, mientras que la diversidadmás importante de las presas (3,1, se registró en el mes de mayo.SummaryFor the food mode determination of the North African green frog Rana(Pelophylax saharica, 360 specimens were collected from 2 lakes in theNorthern area of Tunisia since April until September. We noted that thepreys belong mainly to the Arthropods, particularly Coleopters (38.29%and Dipterous (23.47%. More occasionally, some tadpoles and youngfrogs belonging to the same species as well as other aquatic preys werealso discovered in the stomach contents. The highest number of prey(231 was observed in June, whereas the most important prey diversity(3,1 was recorded in May.

  6. Effects of predatory fish on survival and behavior of larval gopher frogs (Rana capito) and Southern Leopard Frogs (Rana sphenocephala)

    Science.gov (United States)

    Gregoire, D.R.; Gunzburger, M.S.

    2008-01-01

    Southern Leopard Frogs, Rana sphenocephala, are habitat generalists occurring in virtually all freshwater habitats within their geographic range, whereas Gopher Frogs, Rana capito, typically breed in ponds that do not normally contain fish. To evaluate the potential for predation by fish to influence the distribution of these species, we conducted a randomized factorial experiment. We examined the survival rate and behavior of tadpoles when exposed to Warmouth Sunfish, Lepomis gulosus, Banded Sunfish, Enneacanthus obesus, and Eastern Mosquitofish, Gambusia holbrooki. We also conducted a choice experiment to examine the survival rate of the two species of tadpoles when a predator is given a choice of both species simultaneously. Lepomis gulosus consumed the most tadpoles and ate significantly more tadpoles of R. capito than R. sphenocephala. Gambusia holbrooki injured the most tadpoles, especially R. capito. Enneacanthus obesus did not have an effect on behavior or survival of either anuran species. Tadpoles of both anurans increased hiding when in the presence of L. gulosus and G. holbrooki, but a greater proportion of R. capito hid than did R. sphenocephala. Our results suggest that R. capito are more vulnerable to predation by fish than are R. sphenocephala. The introduction of fish may play a role in population declines of certain anurans breeding in normally fish-free wetlands, and even small fish, such as mosquitofish, may have significant negative effects on the tadpoles of R. capito. Copyright 2008 Society for the Study or Amphibians and Reptiles.

  7. Modelling the firing pattern of bullfrog vestibular neurons responding to naturalistic stimuli

    Science.gov (United States)

    Paulin, M. G.; Hoffman, L. F.

    1999-01-01

    We have developed a neural system identification method for fitting models to stimulus-response data, where the response is a spike train. The method involves using a general nonlinear optimisation procedure to fit models in the time domain. We have applied the method to model bullfrog semicircular canal afferent neuron responses during naturalistic, broad-band head rotations. These neurons respond in diverse ways, but a simple four parameter class of models elegantly accounts for the various types of responses observed. c1999 Elsevier Science B.V. All rights reserved.

  8. New Replacement Name for Rana paradoxa Mocquard, 1890 with Designations of Lectotypes for Rana paradoxa and Rana conspicil-lata Günther, 1872:Both Synonymized with Limnonectes kuhlii (Tschudi, 1838) (Dicroglossidae:Dicroglossinae)

    Institute of Scientific and Technical Information of China (English)

    Masafumi MATSUI; Alain DUBOIS; Annemarie OHLER

    2013-01-01

    Fanged frogs, now called Limnonectes kuhlii, from Borneo are remotely related to true Javanese L. kuhlii. For future taxonomy of Bornean fanged frogs, we ifx the nomenclatural status of two existing names, Rana conspicillata Günther, 1872 and Rana paradoxa Mocquard, 1890. Morphological comparison of the type-series revealed heterospeciifc relationships of the two species. For R. conspicillata, we designate BMNH 1947.2.29.20 as the lectotype, and for R. para-doxa, we also designate MNHN 1889.222 as the lectotype and propose a replacement name Limnonectes mocquardi, in order to stabilize their nomenclature.

  9. Western spotted frog (Rana pretiosa) distribution in the Bonneville Basin of western Utah: Research in progress

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides information on the western spotted frog Rana pretiosa which occurs in Tule Valley, Utah. The following topics are discussed; general...

  10. The Developmental Effects Of A Municipal Wastewater Effluent On The Northern Leopard Frog, Rana pipiens

    Science.gov (United States)

    Wastewater effluents are complex mixtures containing a variety of anthropogenic compounds, many of which are known endocrine disruptors. In order to characterize the development and behavorial effects of such a complex mixture, northern leopard frogs, Rana pipiens, were e...

  11. Widespread bacterial infection affecting Rana temporaria tadpoles in mountain areas

    Directory of Open Access Journals (Sweden)

    Rocco Tiberti

    2011-06-01

    Full Text Available Periodic mass die-offs of Rana temporaria tadpole populations have occurred in the ponds of prealpine mountain areas of Brescia (northern Italy since the early 2000s. The author reports some observational data and analytical results from three sites: tadpoles from mortality events had erythema, especially on the legs, suggestive of septicemia. Bacterial culture of these tadpoles revealed Aeromonas hydrophila and Aeromonas sobria, two organisms often associated with Red leg disease. Egg mass counts from 29 pastureland ponds did not revealed breeding activity declines over five years in the Monte Guglielmo area. Aeromonas hydrophila and Aeromonas sobria usually behave as opportunistic bacteria that can become pathogenic after suppression of the immune system by endogenous or exogenous stressors. Thus, a plurality of environmental factors may contribute to mortality events; some of them are discussed, including loss of high altitude breeding ponds resulting in overcrowding and poor water quality in remaining ponds and the presence of other pathogens.

  12. Organically bound tritium in fishes at Rana Pratap Sagar lake

    International Nuclear Information System (INIS)

    Tritium is mainly released into environment in the form of tritiated water (HTO). It becomes a part of general hydrosphere and gets equilibrated with body water of aquatic organisms within a short period of time, as they are totally immersed in the water. Tritium present in body water is called tissue free tritium (TFT). Tritium gets incorporated in body tissue, either during the formation of the tissues or by the exchange of tritium with the labile hydrogen sites present in the tissues. It can significantly contribute radiation dose to the aquatic organism and public consuming the aquatic food, as organically bound tritium (OBT) shows longer retention period in the body compared to those of TFT. The estimations of TFT and OBT contents in the variety of fish at Rana Pratap Sagar (RPS) are reported in this paper. An attempt is also made to evaluate the doses to the local residents, due to intake of tritium through the consumption of RPS fish. (author)

  13. LOS FANTASMAS EN RANAS DE ARISTÓFANES

    Directory of Open Access Journals (Sweden)

    Soraya Planchas Gallarte

    2015-05-01

    Full Text Available THE GHOSTS IN ARISTOPHANES’ FROGS. The aim of the following paper is to present and analyze the passages of the comedies of Aristophanes related to ghostly apparitions. By offering an overview of this issue, so recurrent among classical authors, we will be able to sketch, on the one hand, how the Athenian comic playwright configures this topic in one of his works. On the other, by contextualizing Aristophanes’ treatment of ghosts in his genre, we will have the opportunity of focusing on the similarities, and possible innovations introduced by the poet among ancient Greek authors. Keywords: Aristophanes, ghost, Frogs, apparition, comedy. // LOS FANTASMAS EN RANAS DE ARISTÓFANES. Resumen: La finalidad de nuestra investigación consiste principalmente en presentar y analizar aquellos pasajes de las comedias aristofánicas relacionados con el tópico de las apariciones fantasmales. Comenzaremos ofreciendo una visión general de este motivo, tan recurrente entre los autores clásicos, para, a continuación, detenernos exclusivamente en el tratamiento que hizo el comediógrafo ateniense. Creemos que una detenida observación de las similitudes e innovaciones de estas cuestiones nos llevará, en primer lugar, a delimitar una visión concreta del tópico dentro del género cómico y, en segundo lugar, a insertar una pieza clave en el puzle de la concepción de los fantasmas a lo largo de la literatura grecolatina. Palabras clave: Aristófanes, Ranas, fantasmas, apariciones, comedia.

  14. Alimentación de las ranas pardas, Rana gr. temporaria, en el circo de Piedrafita, (Pirineos, España

    Directory of Open Access Journals (Sweden)

    Rodríguez Vieites, D.

    1997-12-01

    Full Text Available Feeding of high Pyrenean mountain brown frogs were studied in the pre-wintering period. The main prey is beetles (44'97o, two-winged flies (12'9% and bees, wasps, ants, etc (11'4%. For the whole of the frogs, the most frequent prey size is the small (smaller than 10 mm. Big frogs tend to consume bigger prey in not ,o. many quantity, while small frogs consume more quantity of preys but smaller in size. From prey way of life, frogs eat mainly terrestrial and aerial preys, although capture of aquatic prey was observed (11'5% and these preys were eaten inside the water.

    Se ha estudiado la dieta de las ranas pardas en alta montaña pirenaica durante el periodo pre-invernal. Las ranas consumen principalmente coleópteros (44'9%, dípteros (12'9% e himenópteros (11'4%. Para el conjunto de todas las ranas estudiadas, las presas más consumidas son las de pequeño tamaño (menores de 10 mm. Las ranas de mayor talla tienden a consumir presas más grandes y en poca cantidad, mientras que las ranas pequeñas consumen más presas aunque de pequeño tamaño. En cuanto a forma de vida las presas más consumidas son terrestres y aéreas, aunque también se ha comprobado la captura de presas acuáticas (11'5% que son consumidas por las ranas dentro del agua.

  15. Fecal collection methods for the determination of protein digestibility in bullfrogs

    Directory of Open Access Journals (Sweden)

    Marta Verardino De Stéfani

    2015-08-01

    Full Text Available Adequate methods for the determination of protein digestibility in bullfrogs are important for the understanding of nutrient utilization. Therefore, this study evaluated two methods of feces collection: intestinal dissection and fecal decantation, using cylindric-conical tanks. Frogs were fed with a commercial diet (45% crude protein which was ground and supplemented with 0.5% chromium oxide III. The frogs were fasted 48h before force-feeding (5% of the animal's live weight. For the decantation method, the animals were sacrificed 36 h after force-feeding and feces were collected directly from the large intestine. For the sedimentation method, feces were collected when they appeared in the tubes attached to the front end of the cylindric tanks. No significant difference (P>0.05 in the apparent digestibility coefficients of crude protein for dietary was observed between the methods tested (74.0% and 76.4% for the dissection and decantation methods, respectively. In conclusion, both methods can be used for the determination of protein digestibility of bullfrog feeds

  16. Efferent control of the electrical and mechanical properties of hair cells in the bullfrog's sacculus.

    Directory of Open Access Journals (Sweden)

    Manuel Castellano-Muñoz

    Full Text Available BACKGROUND: Hair cells in the auditory, vestibular, and lateral-line systems respond to mechanical stimulation and transmit information to afferent nerve fibers. The sensitivity of mechanoelectrical transduction is modulated by the efferent pathway, whose activity usually reduces the responsiveness of hair cells. The basis of this effect remains unknown. METHODOLOGY AND PRINCIPAL FINDINGS: We employed immunocytological, electrophysiological, and micromechanical approaches to characterize the anatomy of efferent innervation and the effect of efferent activity on the electrical and mechanical properties of hair cells in the bullfrog's sacculus. We found that efferent fibers form extensive synaptic terminals on all macular and extramacular hair cells. Macular hair cells expressing the Ca(2+-buffering protein calretinin contain half as many synaptic ribbons and are innervated by twice as many efferent terminals as calretinin-negative hair cells. Efferent activity elicits inhibitory postsynaptic potentials in hair cells and thus inhibits their electrical resonance. In hair cells that exhibit spiking activity, efferent stimulation suppresses the generation of action potentials. Finally, efferent activity triggers a displacement of the hair bundle's resting position. CONCLUSIONS AND SIGNIFICANCE: The hair cells of the bullfrog's sacculus receive a rich efferent innervation with the heaviest projection to calretinin-containing cells. Stimulation of efferent axons desensitizes the hair cells and suppresses their spiking activity. Although efferent activation influences mechanoelectrical transduction, the mechanical effects on hair bundles are inconsistent.

  17. Na/sup +/-dependent transport of /sup 14/C-L-lysine across bullfrog alveolar epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.J.; Crandall, E.D.

    1986-03-01

    Transepithelial transport of the basic amino acid L-lysine has been studied utilizing the isolated intact bullfrog lung mounted in the Ussing chamber. Lungs were excised from doubly pithed bullfrogs and sandwiched between two hemichambers. /sup 14/C-(U)-L-lysine was added to the upstream reservoir of amphibian Ringer solution, while the tissue was short-circuited. Two lungs from the same animal were used simultaneously to determine the two opposite unidirectional fluxes. Downstream and upstream radioactivities were assayed and used to estimate the apparent permeability (P) of the labeled lysine. Results indicate that the apparent P of /sup 14/C-L-lysine measured in the alveolar (M) to the pleural (S) direction is 19.06 (+- 2.84) x 10/sup -7/ cm/s and P in the S to M direction is 3.29 (+- 0.02) x 10/sup -7/ cm/s. When the 100 mM NaCl in the bath was replaced by 110 mM choline chloride, the flux of /sup 14/C-L-lysine from the alveolar to the pleural side decreased to the same value as that in the opposite direction. The flux from the pleural to the alveolar direction in the absence of Na/sup +/ did not change. These results suggest that the alveolar epithelium exhibits Na/sup +/-dependent amino acid (L-lysine) transport in the M->S, but not in the S->M, direction.

  18. Sound duration as a perceptual cue influencing vocal behavior of male bullfrogs

    Science.gov (United States)

    Simmons, Andrea M.

    2002-05-01

    Female frogs of several species use the temporal cue of sound duration to aid in mate choice. Little is known, however, about the sensitivity of male frogs to this cue. Male bullfrogs emit a complex advertisement call to attract females for mating, and to announce territory occupation to other males. In two experiments, the sensitivity of vocalizing male bullfrogs to field playbacks of advertisement calls differing in duration was examined. The number and latency of evoked vocal responses to the stimuli was used as a measure of perception. Males responded with fewer calls, at longer latencies, to stimuli shorter in duration than the standard signal (with a duration at the mean value for the species). Males preferred stimuli longer in duration than the standard signal, responding with more calls at shorter latencies. They did not, however, significantly lengthen their own calls in response to playbacks of long duration signals. This preference for ``supernormal'' stimuli may be an important factor mediating the evolution of communication signals. [Work supported by NIH.

  19. Na+-dependent transport of 14C-L-lysine across bullfrog alveolar epithelium

    International Nuclear Information System (INIS)

    Transepithelial transport of the basic amino acid L-lysine has been studied utilizing the isolated intact bullfrog lung mounted in the Ussing chamber. Lungs were excised from doubly pithed bullfrogs and sandwiched between two hemichambers. 14C-(U)-L-lysine was added to the upstream reservoir of amphibian Ringer solution, while the tissue was short-circuited. Two lungs from the same animal were used simultaneously to determine the two opposite unidirectional fluxes. Downstream and upstream radioactivities were assayed and used to estimate the apparent permeability (P) of the labeled lysine. Results indicate that the apparent P of 14C-L-lysine measured in the alveolar (M) to the pleural (S) direction is 19.06 (+- 2.84) x 10-7 cm/s and P in the S to M direction is 3.29 (+- 0.02) x 10-7 cm/s. When the 100 mM NaCl in the bath was replaced by 110 mM choline chloride, the flux of 14C-L-lysine from the alveolar to the pleural side decreased to the same value as that in the opposite direction. The flux from the pleural to the alveolar direction in the absence of Na+ did not change. These results suggest that the alveolar epithelium exhibits Na+-dependent amino acid (L-lysine) transport in the M->S, but not in the S->M, direction

  20. Can an Invasive Prey Species Induce Morphological and Behavioral Changes in an Endemic Predator? Evidence from a South Korean Snake (Oocatochus rufodorsatus)

    Institute of Scientific and Technical Information of China (English)

    Jun-Haeng HEO; Heon-Joo LEE; Il-Hun KIM; Jonathan J FONG; Ja-Kyeong KIM; Sumin JEONG; Daesik PARK

    2014-01-01

    Introduction of an invasive prey species into an ecosystem may affect an endemic predator’s fitness by altering the prey-predator system. Successful adaptation may allow the endemic predator to eat and control the invasive species, while unsuccessful adaptation may result in extinction of the predator. We examine the possible effects of the invasive North American bullfrog (Rana [Lithobates] catesbeiana) on the endemic Red-backed rat snake (Oocatochus rufodorsatus) in South Korea. We do so by comparing the morphology and behavior of adult and hatchling snakes from bullfrog-exposed (Taean) and bullfrog-unexposed (Hongcheon) populations. Among the seven morphological characteristics investigated, relative tail length (tail length/snout-vent length) of both adults and hatchlings from Taean was significantly greater than that of adults and hatchlings from Hongcheon. Also, adult snakes from Taean had a signiifcantly shorter latency of ifrst tongue lfick in response to prey compared to adults from Hongcheon. This difference was not observed in hatchlings. In other snake species, a longer relative tail length and shorter latency of ifrst tongue lfick are known to improve foraging efifciency, and these characters may be adaptations ofO. rufodorsatus to prey on bullfrogs. This study provides preliminary evidence that the presence of an invasive prey species may cause morphological and behavioral changes in an endemic predator.

  1. Phylogenetic relationships of leopard frogs (Rana pipiens complex) from an isolated coastal mountain range in southern Sonora, Mexico.

    Science.gov (United States)

    Pfeiler, E; Markow, T A

    2008-10-01

    Mitochondrial DNA sequence data from the control region and 12S rRNA in leopard frogs from the Sierra El Aguaje of southern Sonora, Mexico, together with GenBank sequences, were used to infer taxonomic identity and provide phylogenetic hypotheses for relationships with other members of the Rana pipiens complex. We show that frogs from the Sierra El Aguaje belong to the Rana berlandieri subgroup, or Scurrilirana clade, of the R. pipiens group, and are most closely related to Rana magnaocularis from Nayarit, Mexico. We also provide further evidence that Rana magnaocularis and R. yavapaiensis are close relatives. PMID:18625327

  2. A microsatellite-based method for genotyping diploid and triploid water frogs of the Rana esculenta hybrid complex

    DEFF Research Database (Denmark)

    Christiansen, Ditte Guldager

    2005-01-01

    Rana esculenta is a hybrid between Rana lessonae (LL) and Rana ridibunda (RR), and hybrids may be diploid (LR) or triploid (LLR or LRR). Genotypes can be roughly determined from erythrocyte size and morphometry in adult frogs, but accurate genotyping requires more labourious methods. Here I...

  3. THE MOCHE BOTANICAL FROG (La rana botánica mochica

    Directory of Open Access Journals (Sweden)

    Donna McClelland †

    2011-06-01

    Full Text Available Plants and animals with features which identify them as supernaturals characterize the art of the Precolumbian Moche culture of northern Peru. Among these animals is a frog with feline attributes and a consistent association with manioc tubers, stalks, and plants, the Botanical Frog. The Botanical Frog appears to have been patterned on Leptodactylus pentadactylus. It is shown copulating with felines. Fine line painted vessels and ones with low relief decoration show the Botanical Frog performing as part of a ritual involving other animals and cultivated crops, suggesting that the Botanical Frog was associated with agriculture. ESPAÑOL: El arte de la cultura mochica de la costa norte del Perú presenta plantas y animales mostrando rasgos sobrenaturales. Uno de los animales es una rana con elementos felinos y asociada con tubérculos, ramas y plantas de yuca. La Rana Botánica probablemente tiene su origen en Leptodactylus pentadactylus, una rana carnívora de la selva amazónica. La Rana Botánica copula con felinos y, en vasijas pintadas con líneas finas o con escenarios representados en bajorrelieve, toma parte en ceremonias involucrando a otros animales y cosechas domésticas. Parece ser que la Rana Botánica era un ser sobrenatural asociado con la agricultura.

  4. Effects of elevated temperature and pore pressure on the mechanical behavior of Bullfrog tuff

    International Nuclear Information System (INIS)

    Samples of the Bullfrog Member of the Crater Flat Tuff from the depth interval 758.9 to 759.2 m in hole USW-G1 on the Nevada Test Site were tested in triaxial compression. Test conditions were: (1) effective confining pressure to 20 MPa; (2) temperature of 2000C; (3) both dry and with pore water pressures from 3.4 to 5 MPa; and (4) a strain-rate of 10-4/s. The results suggest that the presence of water causes the strength to decrease. In addition, the brittle-ductile transition pressure for this rock was found to be about 15 MPa, regardless of saturation. Below this pressure deformation is characterized by unstable stress drops and the development of a single fracture, and above this pressure deformation is stable and distributed more uniformly throughout the sample

  5. NUPTIAL PAD AMPUTATION IN AN AMERICAN BULLFROG (LITHOBATES CATESBEIANUS) WITH SQUAMOUS CELL CARCINOMA.

    Science.gov (United States)

    Latney, La'Toya V; Miller, Erica; Pessier, Allan P

    2015-12-01

    A 7-yr-old male captive American bullfrog (Lithobates catesbeianus) presented with a 2-wk history of an enlarged, ulcerated nuptial pad on the mediopalmar surface of the first digit of the left carpus. A 3-mm wedge biopsy of the mass was not diagnostic and differentials included an epidermal inclusion cyst or squamous cell carcinoma. No fungal or acid-fast organisms were cultured or noted on impression smear. Wide surgical resection of the mass and associated first digit were performed. Histopathology confirmed squamous cell carcinoma associated with the dermal nuptial gland with neoplastic cells extending close to deep surgical margins. Two months after surgery, no recurrence was noted. Although experimental tumor studies in amphibians are well documented, clinical reports of cutaneous neoplasia management in captive amphibians are scarce. Squamous cell carcinoma should be considered as a differential diagnosis when male anurans present with nuptial gland enlargement. PMID:26667557

  6. Octylphenol induced gene expression in testes of Frog, Rana chensinensis.

    Science.gov (United States)

    Li, Xinyi; Liu, Jia; Zhang, Yuhui

    2016-06-01

    Octylphenol (OP) is an endocrine-disrupting chemical (EDC), which can disrupt the reproductive system. To understand the effect of OP, a subtractive cDNA library was constructed using suppression subtractive hybridization (SSH) to identify alterations of gene transcription in the testes of the frog Rana chensinensis after OP exposure. Two hundred positive clones were selected and 134 sequences of gene fragments were produced from the subtractive library randomly. These genes were identified to be involved in metabolic process, cellular process, biological regulation, stimulus, immune system and female pregnancy process. In order to verify the efficiency of the subtractive cDNA library, PSG9 and PAPP-A were analyzed further as two representatives of differentially expressed transcription genes using semi-quantitative RT-PCR. Our result was the first successful construction of the subtractive cDNA library in frog testes after OP treatment. Based on this cDNA library, OP was shown to affect multiple physiological processes including inducing immune response, disrupting the steroid hormone synthesis and influencing spermatogenesis in the testis by up-regulation of specific genes. PMID:26896894

  7. Detailed mineralogical characterization of the Bullfrog and Tram members USW-G1, with emphasis on clay mineralogy

    Energy Technology Data Exchange (ETDEWEB)

    Bish, D.L.

    1981-10-01

    The detailed mineralogy of the Bullfrog and Tram Members of the Crater Flat Tuff from drill hole USW-G1 has been examined, primarily to characterize fully the amounts and types of clay minerals in the tuffs and the possible effects clay minerals have on rock properties. Results of bulk sample x-ray diffraction analyses agree closely with previous determinations, although slightly higher clay mineral contents were found in this study. X-ray diffraction analysis of fine fractions revealed that the clay minerals in the tuffs are sodium-saturated montmorillonite-beidellites with typical layer charges and no high-charge layers. These smectites are found in virtually all samples of the Bullfrog and Tram, and there is no correlation between the amounts of smectites and the amounts of zeolite, quartz, and feldspar. Smectites are present in both welded and nonwelded horizons and are scarce in some zones with slight-to-absent welding.

  8. Detailed mineralogical characterization of the Bullfrog and Tram members USW-G1, with emphasis on clay mineralogy

    International Nuclear Information System (INIS)

    The detailed mineralogy of the Bullfrog and Tram Members of the Crater Flat Tuff from drill hole USW-G1 has been examined, primarily to characterize fully the amounts and types of clay minerals in the tuffs and the possible effects clay minerals have on rock properties. Results of bulk sample x-ray diffraction analyses agree closely with previous determinations, although slightly higher clay mineral contents were found in this study. X-ray diffraction analysis of fine fractions revealed that the clay minerals in the tuffs are sodium-saturated montmorillonite-beidellites with typical layer charges and no high-charge layers. These smectites are found in virtually all samples of the Bullfrog and Tram, and there is no correlation between the amounts of smectites and the amounts of zeolite, quartz, and feldspar. Smectites are present in both welded and nonwelded horizons and are scarce in some zones with slight-to-absent welding

  9. Occurrence of the amphibian pathogen Batrachochytrium dendrobatidis in the Pacific Northwest

    Science.gov (United States)

    Pearl, C.A.; Bull, E.L.; Green, D.E.; Bowerman, J.; Adams, M.J.; Hyatt, A.; Wente, W.H.

    2007-01-01

    Chytridiomycosis (infection by the fungus Batrachochytrium dendrobatidis) has been associated with amphibian declines in at least four continents. We report results of disease screens from 210 pond-breeding amphibians from 37 field sites in Oregon and Washington. We detected B. dendrobatidis on 28% of sampled amphibians, and we found ??? 1 detection of B. dendrobatidis from 43% of sites. Four of seven species tested positive for B. dendrobatidis, including the Northern Red-Legged Frog (Rana aurora), Columbia Spotted Frog (Rana luteiventris), and Oregon Spotted Frog (Rana pretiosa). We also detected B. dendrobatidis in nonnative American Bullfrogs (Rana catesbeiana) from six sites in western and central Oregon. Our study and other recently published findings suggest that B. dendrobatidis has few geographic and host taxa limitations among North American anurans. Further research on virulence, transmissibility, persistence, and interactions with other stressors is needed to assess the potential impact of B. dendrobatidis on Pacific Northwestern amphibians. Copyright 2007 Society for the Study of Amphibians and Reptiles.

  10. Identification and functional characterization of a dual GABA/taurine transporter in the bullfrog retinal pigment epithelium

    OpenAIRE

    1995-01-01

    Intracellular microelectrodes, fluorescence imaging, and radiotracer flux techniques were used to investigate the physiological response of the retinal pigment epithelium (RPE) to the major retinal inhibitory neurotransmitter, gamma-aminobutyric acid (GABA). GABA is released tonically in the dark by amphibian horizontal cells, but is not taken up by the nearby Muller cells. Addition of GABA to the apical bath produced voltage responses in the bullfrog RPE that were not blocked nor mimicked by...

  11. Microscopic morphology and testis morphometry of captivity-bred Adult bullfrogs (Lithobates catesbeianus Shaw, 1802

    Directory of Open Access Journals (Sweden)

    Jaqueline Carlos

    2009-12-01

    Full Text Available The aim of this work was to study the testicular morphometry of captivity-bred adult bullfrogs. Fifteen young adult male were studied, in the rainy season and a lengthy photoperiod. The GSI was established at 0.15%. The nuclear diameter of germinative and Leydig cells, the nucleolus diameter of Sertoli cells and the area of cysts and tubules were determined and the mean number of ISPC, IISPC and SPT per cyst and the mean number of cysts per tubule was estimated. The nucleoplasmatic proportion of the nucleus of the Leydig cell was 76.22%, indicating less cytoplasmic activity. Eight generations of spermatogonia were found. The spermatogenesis efficiency in meiosis and in mitosis was 63 and 49%, respectively. The spermatogenesis of bullfrog fited in the pattern of other captivity Anurans, with differences as the morphology of Sertoli and Leydig cells nuclei.A morfometria é uma importante ferramenta para a biologia estrutural, permitindo estudos estereológicos e análises quantitativas. Existem muitos pontos a serem esclarecidos sobre a morfometria testicular desta espécie, que objetivamos desvendar neste trabalho. Quinze machos adultos foram estudados, em período chuvoso e de fotoperíodo longo (dezembro, 2000. O IGS encontrado foi de 0.15%. O diâmetro nuclear das células germinativas e da célula de Leydig, o diâmetro nucleolar das células de Sertoli e a área dos cistos e túbulos foram determinados. O número médio de ISPC, IISPC e SPT por cisto e o número médio de cisto por túbulo foi estimado. A proporção nucleoplasmática do núcleo da célula de Leydig foi de 76.22%, indicando pouca atividade citoplasmática. Oito gerações de espermatogônia foram estimadas. A eficiência da espermatogênese na meiose e mitose foi de 63% e49%, respectivamente. A espermatogênese de rãtouro segue os padrões dos demais Anuros de cativeiro, apresentando diferenças nos núcleos das c��lulas de Sertoli e Leydig.

  12. Peripheral innervation patterns of vestibular nerve afferents in the bullfrog utriculus

    Science.gov (United States)

    Baird, Richard A.; Schuff, N. R.

    1994-01-01

    Vestibular nerve afferents innervating the bullfrog utriculus differ in their response dynamics and sensitivity to natural stimulation. They also supply hair cells that differ markedly in hair bundle morphology. To examine the peripheral innervation patterns of individual utricular afferents more closely, afferent fibers were labeled by the extracellular injection of horseradish peroxidase (HRP) into the vestibular nerve after sectioning the vestibular nerve medial to Scarpa's ganglion to allow the degeneration of sympathetic and efferent fibers. The peripheral arborizations of individual afferents were then correlated with the diameters of their parent axons, the regions of the macula they innervate, and the number and type of hair cells they supply. The utriculus is divided by the striola, a narrow zone of distinctive morphology, into media and lateral parts. Utiricular afferents were classified as striolar or extrastriolar according to the epithelial entrance of their parent axons and the location of their terminal fields. In general, striolar afferents had thicker parent axons, fewer subepithelial bifurcations, larger terminal fields, and more synaptic endings than afferents in extrstriolar regions. Afferents in a juxtastriolar zone, immediately adjacent to the medial striola, had innervation patterns transitional between those in the striola and more peripheral parts of the medial extrastriola. moast afferents innervated only a single macular zone. The terminal fields of striolar afferents, with the notable exception of a few afferents with thin parent axons, were generally confined to one side of the striola. Hair cells in the bullfrog utriculus have perviously been classified into four types based on hair bundle morphology. Afferents in the extrastriolar and juxtastriolar zones largely or exclusively innervated Type B hair cells, the predominant hair cell type in the utricular macula. Striolar afferents supplied a mixture of four hair cell types, but largely

  13. Barevný polymorfismus skokana hnědého (Rana temporaria). Fakt nebo artefakt?

    Czech Academy of Sciences Publication Activity Database

    Hejtmánková, M.; Bureš, S.; Gvoždík, Lumír

    Brno : Ústav biologie obratlovců AV ČR, 2006 - (Bryja, J.; Zukal, J.). s. 144 ISBN 80-903329-4-3. [Zoologické dny. 09.02.2006-10.02.2006, Brno] Institutional research plan: CEZ:AV0Z60930519 Keywords : Rana temporaria Subject RIV: EG - Zoology

  14. Long-Term United Kindrom Trends in the Breeding Phenology of the Common Frog, Rana temporaria

    Czech Academy of Sciences Publication Activity Database

    Scott, W.A.; Pithart, David; Adamson, J. K.

    2008-01-01

    Roč. 42, č. 1 (2008), s. 89-96. ISSN 0022-1511 Institutional research plan: CEZ:AV0Z60870520 Keywords : Long-term * Common Frog * Breeding * Rana temporaria Subject RIV: EG - Zoology Impact factor: 0.888, year: 2008

  15. Pattern formation in artificially activated ectoderm (Rana pipiens and Ambystoma punctatum)

    NARCIS (Netherlands)

    Nieuwkoop, P.D.

    1963-01-01

    Presumptive ectoneuroderm of late blastulae or early gastrulae of Rana pipiens was partially activated by short-lasting disaggregation in Ca-free Holtfreter or Niu-Twitty solutions and subsequent reaggregation in normal solutions. The explants usually became dumbbell shaped and consisted respectivel

  16. Sensitivity of frogs (Rana arvalis) which live in radionuclide contaminated territories to additional colchicine treatment

    International Nuclear Information System (INIS)

    Frogs (Rana arvalis) were caught in villages Babichi (> 2.0 kBq/kg) and Ratomka (< 0.1 kBq/kg). Bone marrow and spleen have been tested to leucocyte with apoptosis indication. After injection of colchicines (10 mg/kg) it was discovered increasing number of cells with pycnosis symptom. The result depends on type of analysed tissue and season

  17. Radioimmunoassay of plasma corticotropin in the edible Frog Rana esculenta L

    International Nuclear Information System (INIS)

    In the green Frog (Rana esculenta) the plasma contains a polypeptide immunologically related to human and porcine corticotropins. A radioimmunoassay capable of detecting 4.10-12 g hog ACTH has been used for a direct plasma ACTH assay in the Frog. Using this method the ACTH rate was determined both in untreated frogs and in animals under various experimental conditions

  18. Delayed metamorphosis and recurrence of bacterial infection in irradiated Rana clamitans tadpoles

    International Nuclear Information System (INIS)

    X-ray doses of 5 and 10 Gy (1 Gy/min) given to premetamorphic Green Frog (Rana clamitans) tadpoles delayed their metamorphosis relative to unirradiated controls. Previous pathogenic bacterial infections recurred in irradiated animals prior to metamorphic climax. Limited mortality occurred during metamorphic climax, 80-105 days after irradiation

  19. Biophotons Contribute to Retinal Dark Noise.

    Science.gov (United States)

    Li, Zehua; Dai, Jiapei

    2016-06-01

    The discovery of dark noise in retinal photoreceptors resulted in a long-lasting controversy over its origin and the underlying mechanisms. Here, we used a novel ultra-weak biophoton imaging system (UBIS) to detect biophotonic activity (emission) under dark conditions in rat and bullfrog (Rana catesbeiana) retinas in vitro. We found a significant temperature-dependent increase in biophotonic activity that was completely blocked either by removing intracellular and extracellular Ca(2+) together or inhibiting phosphodiesterase 6. These findings suggest that the photon-like component of discrete dark noise may not be caused by a direct contribution of the thermal activation of rhodopsin, but rather by an indirect thermal induction of biophotonic activity, which then activates the retinal chromophore of rhodopsin. Therefore, this study suggests a possible solution regarding the thermal activation energy barrier for discrete dark noise, which has been debated for almost half a century. PMID:27059222

  20. The Current and Historical Distribution of Special Status Amphibians at the Livermore Site and Site 300

    Energy Technology Data Exchange (ETDEWEB)

    Hattem, M V; Paterson, L; Woollett, J

    2008-08-20

    65 surveys were completed in 2002 to assess the current distribution of special status amphibians at the Lawrence Livermore National Laboratory's (LLNL) Livermore Site and Site 300. Combined with historical information from previous years, the information presented herein illustrates the dynamic and probable risk that amphibian populations face at both sites. The Livermore Site is developed and in stark contrast to the mostly undeveloped Site 300. Yet both sites have significant issues threatening the long-term sustainability of their respective amphibian populations. Livermore Site amphibians are presented with a suite of challenges inherent of urban interfaces, most predictably the bullfrog (Rana catesbeiana), while Site 300's erosion issues and periodic feral pig (Sus scrofa) infestations reduce and threaten populations. The long-term sustainability of LLNL's special status amphibians will require active management and resource commitment to maintain and restore amphibian habitat at both sites.

  1. SEPTICEMIA EM GIRINOS DE CRIAÇÃO NA FASE PRÉ-METAMÓRFICA

    Directory of Open Access Journals (Sweden)

    Rolando Alfredo Mazzoni

    2012-03-01

    Full Text Available Herein we describe septicemic outbreaks affecting pre-metamorphic bullfrog tadpoles (Rana [Lithobates] catesbeiana Shaw, 1802. The survey was performed in three commercial frog farms located in Goiás State. Clinical assessment and tadpole sampling for necropsy, histopathology, microbiology, parasitology, transmission electronic microscopy and molecular studies were performed. Septicemic outbreaks were characterized by edema, ascites and nervous signs. Main etiological agents identified were Gram-positive cocci. Lesions were more prevalent in liver and kidney, but they were also found in other internal organs. Typical lesions were degeneration and necroses associated to mononuclear lympohcytes and granuloma formation. The disease may be considered as a “secondary streptococcal septicemia”. It was not possible to determine the primary cause preceding tissue colonization by streptococci, but the intensive husbandry practices might have an important role.

  2. Low levels of cadmium chloride alter the immunoprecipitation of corneal cadherin-complex proteins.

    Science.gov (United States)

    Weidner, W J; Waddell, D S; Sillman, A J

    2000-12-01

    The effect of cadmium chloride on the immunoprecipitation of cadherin and the associated adherens junctional proteins, alpha- and beta-catenin, was examined in isolated bullfrog (Rana catesbeiana) corneas utilizing Western blot and enhanced chemoluminescent techniques. Application of either 1.0 microM or 75.0 microM CdCl2 to the corneal endothelium for 2 h markedly decreased the immunoprecipitation of cadherins as compared to paired control corneas. Immunoprecipitation of alpha-catenin was increased in response to both doses of CdCl2, while the immunoprecipitation of beta-catenin was little changed by either cadmium dose. There is accumulating evidence that cadmium may increase epithelial paracellular permeability by interfering with cadherin complex activity at intercellular junctions. The present study suggests that inorganic cadmium in low micromolar concentrations may decrease the integrity of the corneal endothelium, at least in part through a similar mechanism involving disruption of junctional cadherin complex function. PMID:11201663

  3. Low levels of cadmium chloride after the immunoprecipitation of corneal cadherin-complex proteins

    Energy Technology Data Exchange (ETDEWEB)

    Weidner, W.J.; Waddell, D.S.; Sillman, A.J. [California Univ., Davis, CA (United States). Div. of Biological Sciences

    2000-12-01

    The effect of cadmium chloride on the immunoprecipitation of cadherin and the associated adherens junctional proteins, {alpha}- and {beta}-catenin, was examined in isolated bullfrog (Rana catesbeiana) corneas utilizing Western blot and enhanced chemoluminescent techniques. Application of either 1.0 {mu}M or 75.0 {mu}M CdCl{sub 2} to the corneal endothelium for 2 h markedly decreased the immunoprecipitation of cadherins as compared to paired control corneas. Immunoprecipitation of {alpha}-catenin was increased in response to both doses of CdCl{sub 2}, while the immunoprecipitation of {beta}-catenin was little changed by either cadmium dose. There is accumulating evidence that cadmium may increase epithelial paracellular permeability by interfering with cadherin complex activity at intercellular junctions. The present study suggests that inorganic cadmium in low micromolar concentrations may decrease the integrity of the corneal endothelium, at least in part through a similar mechanism involving disruption of junctional cadherin complex function. (orig.)

  4. Elevage commercial de grenouilles en Malaisie

    Directory of Open Access Journals (Sweden)

    Hardouin, J.

    1997-01-01

    Full Text Available Commercial Frog Production in Malaysia. Commercial frog farms exist in several countries. It seems hopeless believing that frog leg consumption can be prohibited, and the solution is probably a very strict control of the origin of the legs sold and imported. Uncontrolled hunting-poaching of frogs should be replaced by sustainable and rational breeding of frogs for sale. A large frog farm located near Singapore is described with the infrastructure and the management of the production. The two species bred are the American and the Asian bull-frogs Rana catesbeiana and R. tigerina. It is also mentioned that appropriate slaughtering techniques exist for frogs based on same guidelines as for conventional farm animals.

  5. Morfologfa conchffera, crecimiento, reproducción y letargo de los caracoles gigantes africanos : observaciones en laboratorio sobre Archachatina marginata suturalis, Achatina achatina y Achatina fulica'

    Directory of Open Access Journals (Sweden)

    Stiévenart, C.

    1997-01-01

    Full Text Available hell Shape, Growth, Reproduction and Estivation in Giant African Landsnails : Observations in Laboratory on"Archachatina marginata suturalis, Achatina achatina and Achatina fulica". Commercial frog farms exist in several countries. It seems hopeless believing that frog leg consumption can be prohibited, and the solution is probably a very strict control of the origin of the legs sold and imported. Uncontrolled hunting-poaching of frogs should be replaced by sustainable and rational breeding of frogs for sale. A large frog farm located near Singapore is described with the infrastructure and the management of the production. The two species bred are the American and the Asian bull-frogs Rana catesbeiana and R. tigerina. It is also mentioned that appropriate slaughtering techniques exist for frogs based on same guidelines as for conventional farm animals.

  6. Hair cell tufts and afferent innervation of the bullfrog crista ampullaris

    Science.gov (United States)

    Myers, Steven F.; Lewis, Edwin R.

    1990-01-01

    Within the bullfrog semicircular canal crista, hair cell tuft types were defined and mapped with the aid of scanning electron microscopy. Dye-filled planar afferent axons had mean distal axonal diameters of 1.6-4.9 microns, highly branched arbors, and contacted 11-24 hair cells. Dye-filled isthmus afferent axons had mean distal axonal diameters of 1.8-7.9 microns, with either small or large field arbors contacting 4-9 or 25-31 hair cells. The estimated mean number of contacts per innervated hair cell was 2.2 for planar and 1.3 for isthmus afferent neurons. Data on evoked afferent responses were available only for isthmus units that were observed to respond to our microrotational stimuli. Of 21 such afferent neurons, eight were successfully dye-filled. Within this sample, high-gain units had large field arbors and lower-gain units had small field arbors. The sensitivity of each afferent neuron was analyzed in terms of noise equivalent input (NEI), the stimulus amplitude for which the afferent response amplitude is just equivalent to the rms deviation of the instantaneous spike rate. NEI for isthmus units varied from 0.63 to 8.2 deg/s; the mean was 3.2 deg/s.

  7. Geologic map of the Northeast quarter of the Bullfrog 15-minute quadrangle, Nye County, Nevada

    International Nuclear Information System (INIS)

    This study of the northeast quarter of the Bullfrog 15-minute quadrangle was undertaken to determine the stratigraphy and structural setting as part of a regional study in cooperation with the US Department of Energy. Geology was mapped on aerial photographs at a scale of 1:24,000. Alluvial deposits were mapped on photographs and field checked in some cases. Outcrops of Cambrian and Proterozoic rocks in the southeast corner of the map area were taken from mapping by Monsen (1983). Thickness of units are approximate due to varying degrees of internal deformation. Identification of units is queried on the map where it is uncertain. Field terms guided by some petrographic work are used for lava flows and dikes; therefore, latite-type rocks are termed ''latitic,'' dacite-type rocks are ''dacitic,'' and so forth. Crystal content and amount are approximate for units younger than Tbt6. Age determinations for the rock units have been corrected for new K-Ar constants (Dalrymple, 1979). A detachment fault (Maldonado, 1985, 1988) is defined for this study as ''hor-ellipsis a low-angle normal fault that formed at a low angle, has significant displacement, and is of subregional extent'' (Reynolds and Spencer, 1985). The area was previously mapped by Ransome and others (1910) and by Cornwall and Kleinhampl (1961, 1964). A detailed discussion of the structural setting of the area is presented in a paper by Maldonado. 17 refs

  8. Hair cell regeneration in the bullfrog vestibular otolith organs following aminoglycoside toxicity

    Science.gov (United States)

    Baird, Richard A.; Torres, M. A.; Schuff, N. R.

    1994-01-01

    Adult bullfrogs were given single intraotic injections of the aminoglycoside antibiotic gentamicin sulfate and sacrificed at postinjection times ranging from 0.5 to 9 days. The saccular and utricular maculae of normal and injected animals were examined in wholemount and cross-section. Intraotic 200 (mu) M gentamicin concentrations resulted in the uniform destruction of the hair bundles and, at later times, the cell bodies of saccular hair cells. In the utriculus, striolar hair cells were selectively damaged while extrastriolar hair cells were relatively unaffected. Regenerating hair cells, identified in sectioned material by their small cell bodies and short, well-formed hair bundles, were seen in the saccular and utricular maculae as early as 24-48 h postinjection. Immature versions of mature hair cell types in both otolith organs were recognized by the presence of absence of a bulbed kinocilia and the relative lengths of their kinocilia and longest sterocilia. Utricular hair cell types with kinocilia longer than their longest stereocilia were observed at earlier times than hair cell types with shorter kinocilia. In the same sacculus, the hair bundles of gentamicin-treated animals, even at 9 days postinjection, were significantly smaller than those of normal animals. The hair bundles of utricular hair cells, on the other hand, reached full maturity within the same time period.

  9. Greater ATP dependence than sodium dependence of radiocalcium efflux in bullfrog ventricle

    International Nuclear Information System (INIS)

    45Ca efflux was studied in intact bullfrog ventricles following a 2-h period of loading with radiocalcium-containing Ringer solution. The cannulated ventricle was placed in a closed air-filled container to which were applied rhythmic, electronically timed, positive- and negative-pressure pulsations, which induced ventricular volume excursions. The mechanical arrangement and timing circuitry made it possible for each period to be as short in duration as 15 s. By use of this technique, penetration of the extracellular space by [14C]inulin was found to be complete within 30 s, and recovery of the inulin proceeded with a time constant of 17-24 s, indicating a completeness of recovery of 98% within 90 s. Washout of added 45Ca was quantitatively quite close to that of inulin, and in addition the estimated rate of sequestration of the isotope was slow enough to introduce only a small error into the experimental results. 45Ca efflux was only slightly (15%) sensitive to replacement of extracellular sodium but was profoundly sensitive to the inhibitors of ATP synthesis, cyanide and 2-deoxy-glucose

  10. Reaction of Bullfrog tuff with J-13 well water at 900C and 1500C

    International Nuclear Information System (INIS)

    A series of experiments was conducted on crushed tuff at 900C and 1500C and on core wafer samples at 1500C. The results show the following: increasing the ratio of rock to water increases the rate of approach to steady-state concentrations in solution. Surface outcrop samples of Bullfrog tuff contain a minor component of highly soluble material believed to be a residue from the evaporation of surface runoff water in the pores of the rock. This material can be removed by shaking the crushed rock with water at room temperature and subjecting it briefly to heat with fresh water. Solution analyses for unfiltered samples that have reacted for short periods show higher concentrations of Al and Fe than do analyses for filtered samples; results for other elements are independent of filtration. This difference probably exists because of particulate matter in the solutions that dissolves when the samples are acidified prior to analysis. Agitation of samples during reaction produces sub-0.1 μ particles in the solutions. These particles dissolve when samples are acidified, resulting in abnormally high concentration values for some elements, such as Al and Fe. Comparison of the results for crushed rock with those for core wafers shows that the method of sample preparation does not have a large effect on the results of rock-water interaction studies

  11. Hair cell recovery in mitotically blocked cultures of the bullfrog saccule

    Science.gov (United States)

    Baird, R. A.; Burton, M. D.; Fashena, D. S.; Naeger, R. A.

    2000-01-01

    Hair cells in many nonmammalian vertebrates are regenerated by the mitotic division of supporting cell progenitors and the differentiation of the resulting progeny into new hair cells and supporting cells. Recent studies have shown that nonmitotic hair cell recovery after aminoglycoside-induced damage can also occur in the vestibular organs. Using hair cell and supporting cell immunocytochemical markers, we have used confocal and electron microscopy to examine the fate of damaged hair cells and the origin of immature hair cells after gentamicin treatment in mitotically blocked cultures of the bullfrog saccule. Extruding and fragmenting hair cells, which undergo apoptotic cell death, are replaced by scar formations. After losing their bundles, sublethally damaged hair cells remain in the sensory epithelium for prolonged periods, acquiring supporting cell-like morphology and immunoreactivity. These modes of damage appear to be mutually exclusive, implying that sublethally damaged hair cells repair their bundles. Transitional cells, coexpressing hair cell and supporting cell markers, are seen near scar formations created by the expansion of neighboring supporting cells. Most of these cells have morphology and immunoreactivity similar to that of sublethally damaged hair cells. Ultrastructural analysis also reveals that most immature hair cells had autophagic vacuoles, implying that they originated from damaged hair cells rather than supporting cells. Some transitional cells are supporting cells participating in scar formations. Supporting cells also decrease in number during hair cell recovery, supporting the conclusion that some supporting cells undergo phenotypic conversion into hair cells without an intervening mitotic event.

  12. Three New Localities for Rana bedriagae caralitana Arıkan, 1988 (Anura: Ranidae) in the West Mediterranean Region

    OpenAIRE

    DÜŞEN, Serdar; Öz, Mehmet; TUNÇ, Mehmet Rızvan

    2004-01-01

    Thirty adult (16 males 14 females) Rana bedriagae caralitana specimens were investigated morphologically. According to results of the morphological analysis, the Kırkgöz (Antalya), Taşkesiği (Korkuteli/Antalya) and Girdev Plateau (Elmalı/Antalya) populations were included in Rana bedriagae caralitana. Furthermore, the distribution range of R. b. caralitana was extended to the northern part of the west Mediterranean Region.

  13. Chromosome Aberrations of East Asian Bullfrog (Hoplobatrachus rugulosus around a Gold Mine Area with Arsenic Contamination

    Directory of Open Access Journals (Sweden)

    Atidtaya Suttichaiya

    2016-01-01

    Full Text Available The objectives of this study are to investigate the chromosome aberrations of the East Asian Bullfrog (Hoplobatrachus rugulosus in the gold mine area compared to an unaffected area. Three H. rugulosus were collected, and chromosome aberrations were studied using bone marrow. The level of arsenic was measured in water, sediment and H. rugulosus samples. The average concentrations of arsenic in the water and sediment samples from the gold mine and unaffected areas were 0.03 ± 0.003 mg/l and not detected in water as well as 351.59 ± 5.73 and 1.37 ± 1.07 mg/kg in sediment, respectively. The gold mine values were higher than the permissible limit of the water and soil quality standards, but the arsenic concentrations in the samples from the unaffected area were within prescribed limit. The average concentrations of arsenic in H. rugulosus samples from the gold mine and unaffected areas were 0.39 ± 0.30 and 0.07 ± 0.01 mg/kg, respectively, which were both lower than the standard of arsenic contamination in food. The diploid chromosome number of H. rugulosus in both areas was 2n=26, and the percentage of chromosome breakages of H. rugulosus in the gold mine area were higher than the unaffected area. There were eight types of chromosome aberrations, including a single chromatid gap, isochromatid gap, single chromatid break, isochromatid break, centric fragmentation, deletion, fragmentation and translocation. The most common chromosome aberration in the samples from the affected area was deletion. The difference in the percentage of chromosome breakages in H. rugulosus from both areas was statistically significant (p<0.05.

  14. Ultrastructure and localisation of late-sporogonic developmental stages of Sphaerospora ranae (Myxosporea: Sphaerosporidae)

    Czech Academy of Sciences Publication Activity Database

    Jirků, Miloslav; Bartošová, Pavla

    2014-01-01

    Roč. 61, č. 4 (2014), s. 311-321. ISSN 0015-5683 R&D Projects: GA ČR GAP506/10/2330; GA ČR(CZ) GPP506/11/P724 Institutional support: RVO:60077344 Keywords : Amphibia * Anura * Europe * kidneys * myxospore * Myxozoa * Rana * sporogony * synchronisation * in situ hybridisation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.147, year: 2014

  15. Data regarding the trophic spectrum of a population of Rana esculenta Complex from Bacau County

    OpenAIRE

    Daniel GHIURCA; Lacramioara ZAHARIA

    2006-01-01

    We analyzed the trophic spectrum of one population of Rana esculenta complex collected, placed close to the lake accumulation Bacău II. The most abundant prey taxons in the food of edible frog are species from Coleoptera order, followed by Hymenoptera and Diptera among insects and Aranee among spiders. We identified a great number of gregarious small species (Formicidae) showing an opportunistic predator behavior of this frogs, using the sit and wait foraging behavior. The terrestrial preys p...

  16. The Effects of nitrite on behavior and metamorphosis in cascades frogs ( Rana cascadae)

    OpenAIRE

    Marco, Adolfo; Blaustein, Andrew R

    1999-01-01

    Amphibian metamorphosis is a period of drastic morphologic reorganization, during which larvae experience a decrease in locomotor ability and are more vulnerable to predation. Our results indicate that exposure to sublethal concentrations of nitrite in the water induces behavioral and morphologic changes in the Cascades frog (Rana cascadae). Tadpoles exposed to a nitrite concentration of N-NO— at 3.5 mg/L transformed more slowly than control tadpoles exposed to dechlorinate...

  17. On possibility of use of lake frog (Rana ridibunda as a raw material

    Directory of Open Access Journals (Sweden)

    Dinh Van Hai

    2013-04-01

    Full Text Available The technological properties such as physical and chemical compositions, energy value of the muscle tissue of the lake frog(Rana ridibunda have been studied. They have been compared with the indicators of the objects usual to their use in food. Studies have shown the value of the species of amphibians that have not found wide application in the food industry in Russia. It is shown that the lake frog can be used in the specific products.

  18. Data on the isolation of immunoglobulin from the serum of the green frog: Rana esculenta

    OpenAIRE

    Stošić Svetlana; Divjak Isidora; Ješić Snežana; Nešić V.; Račić A.; Popović Nada

    2006-01-01

    Even though the green frog (Rana esculenta) is often used as an experimental model for further studies of physiological laws, little is still known about its serum proteins and their role in immunity. Its serum proteins have been studied quite extensively, as when they are taken up into the organism of another animal they represent antigens themselves. In this work, an attempt was made to isolate some frog serum proteins and to investigate the electrophoretic qualities of the isolated compone...

  19. Food Composition of the Marsh Frog, Rana ridibunda Pallas, 1771, in Thrace

    OpenAIRE

    Kerim ÇİÇEK; Ahmet MERMER

    2007-01-01

    The purpose of this investigation was to determine the feeding habits of the marsh frog, Rana ridibunda, populations inhabiting Turkish Thrace. Analysis of the stomach contents of 53 (19 males, 34 females) adult individuals was performed. The frog diet consisted of a wide variety of arthropods; Diptera (42.62%) and Coleoptera (21.84%) were especially prominent. Aquatic forms did not contribute much to the frog diet. The prey items identified indicate that individuals of this species, like oth...

  20. Assessing Historical and Current Threats to Common Frog (Rana Temporaria) Populations in Ireland

    OpenAIRE

    Reid, Neil; Dingerkus, Karina; Stone, Richard; Buckley, John; Beebee, Trevor; Marnell, Ferdia; Wilkinson, John

    2013-01-01

    Ponds are an ephemeral feature of the landscape but their large-scale loss can have profound implications for biodiversity and the persistence of amphibian populations. We quantified rates of pond loss throughout Ireland over a period of approximately 125 yr. Environmental parameters and perceived risk factors associated with the current occurrence and density of the Common Frog, Rana temporaria, were also analyzed. The numbers of farmland ponds declined by 54% between 1887–1913 and 2005–11, ...

  1. N.C. Rana: The Life of a `Comet' in the Astrophysical World

    CERN Document Server

    Mukhopadhyay, Utpal

    2014-01-01

    Narayan Chandra Rana, a person with extraordinary potential from a remote village of Bengal, India, came into the limelight of the international scientific world through his exceptional talent, zeal and courage. In his very short life-span, he excelled not only into various branches of astrophysics, but also took a leading role in science popularization, text book writing etc. In this paper, life and works of that budding scientist of India have been discussed from multifarious viewpoints.

  2. Effects of ghrelin and motilin on smooth muscle contractility of the isolated gastrointestinal tract from the bullfrog and Japanese fire belly newt.

    Science.gov (United States)

    Kitazawa, Takio; Shimazaki, Misato; Kikuta, Ayumi; Yaosaka, Noriko; Teraoka, Hiroki; Kaiya, Hiroyuki

    2016-06-01

    Ghrelin has been identified in some amphibians and is known to stimulate growth hormone release and food intake as seen in mammals. Ghrelin regulates gastrointestinal motility in mammals and birds. The aim of this study was to determine whether ghrelin affects gastrointestinal smooth muscle contractility in bullfrogs (anuran) and Japanese fire belly newts (urodelian) in vitro. Neither bullfrog ghrelin nor rat ghrelin affected longitudinal smooth muscle contractility of gastrointestinal strips from the bullfrog. Expression of growth hormone secretagogue receptor 1a (GHS-R1a) mRNA was confirmed in the bullfrog gastrointestinal tract, and the expression level in the gastric mucosa was lower than that in the intestinal mucosa. In contrast, some gastrointestinal peptides, including substance P, neurotensin and motilin, and the muscarinic receptor agonist carbachol showed marked contraction, indicating normality of the smooth muscle preparations. Similar results were obtained in another amphibian, the Japanese fire belly newt. Newt ghrelin and rat ghrelin did not cause any contraction in gastrointestinal longitudinal muscle, whereas substance P and carbachol were effective causing contraction. In conclusion, ghrelin does not affect contractility of the gastrointestinal smooth muscle in anuran and urodelian amphibians, similar to results for rainbow trout and goldfish (fish) but different from results for rats and chickens. The results suggest diversity of ghrelin actions on the gastrointestinal tract across animals. This study also showed for the first time that motilin induces gastrointestinal contraction in amphibians. PMID:26704852

  3. Expression and localization of prohormone convertase PC1 in the calcitonin-producing cells of the bullfrog ultimobranchial gland.

    Science.gov (United States)

    Yaoi, Yuichi; Suzuki, Masakazu; Tomura, Hideaki; Kurabuchi, Shingo; Sasayama, Yuichi; Tanaka, Shigeyasu

    2003-11-01

    We examined the expression and localization of the prohormone convertases, PC1 and PC2, in the ultimobranchial gland of the adult bullfrog using immunohistochemical (IHC) and in situ hybridization (ISH) techniques. In the ultimobranchial gland, PC1-immunoreactive cells were columnar, and were present in the follicular epithelium. When serial sections were immunostained with anti-calcitonin, anti-CGRP, anti-PC1, and anti-PC2 sera, PC1 was found only in the calcitonin/CGRP-producing cells. No PC2-immunopositive cells were detected. In the ISH, PC1 mRNA-positive cells were detected in the follicle cells in the ultimobranchial gland. No PC2 mRNA-positive cells were detected. RT-PCR revealed expression of the mRNAs of PC1 and the PC2 in the ultimobranchial gland. However, very little of the PC2 mRNA is probably translated because no PC2 protein was detected either by IHC staining or by Western blotting analysis. We conclude that the main prohormone convertase that is involved in the proteolytic cleavage of procalcitonin in the bullfrog is PC1. PMID:14566018

  4. Structure and composition of arytenoid cartilage of the bullfrog (Lithobates catesbeianus) during maturation and aging.

    Science.gov (United States)

    Laureano, Priscila Eliane dos Santos; Oliveira, Kris Daiana Silva; de Aro, Andrea Aparecida; Gomes, Laurecir; Pimentel, Edson Rosa; Esquisatto, Marcelo Augusto Marretto

    2015-10-01

    The aging process induces progressive and irreversible changes in the structural and functional organization of animals. The objective of this study was to evaluate the effects of aging on the structure and composition of the extracellular matrix of the arytenoid cartilage found in the larynx of male bullfrogs (Lithobates catesbeianus) kept in captivity for commercial purposes. Animals at 7, 180 and 1080 days post-metamorphosis (n=10/age) were euthanized and the cartilage was removed and processed for structural and biochemical analysis. For the structural analyses, cartilage sections were stained with picrosirius, toluidine blue, Weigert's resorcin-fuchsin and Von Kossa stain. The sections were also submitted to immunohistochemistry for detection of collagen types I and II. Other samples were processed for the ultrastructural and cytochemical analysis of proteoglycans. Histological sections were used to chondrocyte count. The number of positive stainings for proteoglycans was quantified by ultrastructural analysis. For quantification and analysis of glycosaminoglycans were used the dimethyl methylene blue and agarose gel electrophoresis methods. The chloramine T method was used for hydroxyproline quantification. At 7 days, basophilia was observed in the pericellular and territorial matrix, which decreased in the latter over the period studied. Collagen fibers were arranged perpendicular to the major axis of the cartilaginous plate and were thicker in older animals. Few calcification areas were observed at the periphery of the cartilage specimens in 1080-day-old animals. Type II collagen was present throughout the stroma at the different ages. Elastic fibers were found in the stroma and perichondrium and increased with age in the two regions. Proteoglycan staining significantly increased from 7 to 180 days and reduced at 1080 days. The amount of total glycosaminoglycans was higher in 180-day-old animals compared to the other ages, with marked presence of

  5. Community Structure and Function of Amphibian Skin Microbes: An Experiment with Bullfrogs Exposed to a Chytrid Fungus.

    Science.gov (United States)

    Walke, Jenifer B; Becker, Matthew H; Loftus, Stephen C; House, Leanna L; Teotonio, Thais L; Minbiole, Kevin P C; Belden, Lisa K

    2015-01-01

    The vertebrate microbiome contributes to disease resistance, but few experiments have examined the link between microbiome community structure and disease resistance functions. Chytridiomycosis, a major cause of amphibian population declines, is a skin disease caused by the fungus, Batrachochytrium dendrobatidis (Bd). In a factorial experiment, bullfrog skin microbiota was reduced with antibiotics, augmented with an anti-Bd bacterial isolate (Janthinobacterium lividum), or unmanipulated, and individuals were then either exposed or not exposed to Bd. We found that the microbial community structure of individual frogs prior to Bd exposure influenced Bd infection intensity one week following exposure, which, in turn, was negatively correlated with proportional growth during the experiment. Microbial community structure and function differed among unmanipulated, antibiotic-treated, and augmented frogs only when frogs were exposed to Bd. Bd is a selective force on microbial community structure and function, and beneficial states of microbial community structure may serve to limit the impacts of infection. PMID:26445500

  6. Community Structure and Function of Amphibian Skin Microbes: An Experiment with Bullfrogs Exposed to a Chytrid Fungus.

    Directory of Open Access Journals (Sweden)

    Jenifer B Walke

    Full Text Available The vertebrate microbiome contributes to disease resistance, but few experiments have examined the link between microbiome community structure and disease resistance functions. Chytridiomycosis, a major cause of amphibian population declines, is a skin disease caused by the fungus, Batrachochytrium dendrobatidis (Bd. In a factorial experiment, bullfrog skin microbiota was reduced with antibiotics, augmented with an anti-Bd bacterial isolate (Janthinobacterium lividum, or unmanipulated, and individuals were then either exposed or not exposed to Bd. We found that the microbial community structure of individual frogs prior to Bd exposure influenced Bd infection intensity one week following exposure, which, in turn, was negatively correlated with proportional growth during the experiment. Microbial community structure and function differed among unmanipulated, antibiotic-treated, and augmented frogs only when frogs were exposed to Bd. Bd is a selective force on microbial community structure and function, and beneficial states of microbial community structure may serve to limit the impacts of infection.

  7. Data regarding the trophic spectrum of a population of Rana esculenta Complex from Bacau County

    Directory of Open Access Journals (Sweden)

    Daniel GHIURCA

    2006-05-01

    Full Text Available We analyzed the trophic spectrum of one population of Rana esculenta complex collected, placed close to the lake accumulation Bacău II. The most abundant prey taxons in the food of edible frog are species from Coleoptera order, followed by Hymenoptera and Diptera among insects and Aranee among spiders. We identified a great number of gregarious small species (Formicidae showing an opportunistic predator behavior of this frogs, using the sit and wait foraging behavior. The terrestrial preys prevail in comparison with aquatic organisms.

  8. Purification and in vitro Activity of an Antimicrobial Peptide from Skin of Rana Temporaria Chensinensis, David

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jie; MENG Qing-fan; XU Xue-song; TIAN Xiao-le; JIANG Fu-jia; LI Qing-shan; TENG Li-rong

    2007-01-01

    In this study, an antimicrobial component (RTCI) was purified from the skin of Rana temporaria chensinensis,David. Antimicrobial activities of RTCI against clinical multi-drug resistant bacterial strains, including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureaus, Klebsiella oxytoca, Klebsiella pneumoniae, Enterococcus faecalis, and Proteus mirabilis were measured in vitro by means of minimal inhibitory concentration and time-kill studies.The results indicate that RTCI could inhibit the growth of these bacteria at a proper concentration and suggest that RTCI shows a better antimicrobial activity to Gram-negative bacterial strains than to Gram-positive bacterial strains.

  9. CARDIO-RESPIRATORY INTEGRATION IN DIVING BULLFROG Lithobates catesbeianus (Shaw, 1802

    Directory of Open Access Journals (Sweden)

    FERNANDES, Marcelo dos Santos

    2011-11-01

    Full Text Available Cardiac frequency and blood pressure were measured during voluntary diving in the bullfrog,Lithobates catesbeianus, exposed to 15°C or, alternatively, 25°C. Diving caused bradycardia and reduction ofblood pressure. Cardiac frequency was 27.1  2.2 for breath periods and 19.3  2.7 for diving periods at 15°C,and 47.7  4.4 and 35.3  3.6 for 25°C. Systolic blood pressure was 39,6  0,9 for breath periods and 36,2  0,4for diving periods at 15°C, and 42,4  1,0 and 39,8  0,5 at 25°C. Diastolic blood pressure was 32,3  0,6 forbreath periods and 29,5  0,5 for diving periods at 15°C, and 35,3  0,9 and 33,2  0,6 at 25°C. The animal wasartificially ventilated during diving with normoxic, hypoxic (5% O2 and hypercarbic gas mixtures (6% CO2.None of these procedures produced any change of blood pressure or cardiac frequency. Cardio-vascular effectshave, however, been reported in some other studies on amphibians. As a new aspect, we applied artificialventilation during a voluntary dive in the frog. Surfacing, elicited tachycardia and elevated blood pressure, Thesecardiovascular reflexes depend on a stimulus that still needs to be identified.A freqüência cardíaca e a pressão arterial foram medidas durante o mergulho voluntário na rãLithobates catesbeianus, exposto a 15 ° C ou, alternativamente, a 25 ° C. O mergulho causou a bradicardia eredução da pressão arterial. A frequencia cardíaca foi 27.1  2.2 para períodos respiratórios e 19.3  2.7 para osperiodo de mergulho à 15°C, and 47.7  4.4 e 35.3  3.6 à 25°C. A pressão arterial sistólica foi 39,6  0,9 paraos periodos respiratórios e 36,2  0,4 para periods de mergulho à 15°C, e 42,4  1,0 e 39,8  0,5 à 25°C. Apressão diastólica foi 32,3  0,6 para periodos respiratórios e 29,5  0,5 para periodos de mergulho à 15°C, e35,3  0,9 e 33,2  0,6 à 25°C. O animal foi utilizado para ventilação artificial durante o

  10. Effects of Inactivated Streptococcus Aglactiae Vaccineon Immunity in Bullfrog%牛蛙源无乳链球菌全菌疫苗免疫效果研究

    Institute of Scientific and Technical Information of China (English)

    周冬仁; 陈莎莎; 杭小英; 施伟达; 罗毅志; 叶雪平

    2012-01-01

    将分离鉴定的无乳链球菌用0.4%的甲醛灭活,加弗氏完全佐剂制成灭活全菌苗,对牛蛙进行注射免疫.通过测定受免牛蛙血清中凝集抗体效价,总蛋白、免疫球蛋白的测定及免疫保护率的测定,探讨疫苗的免疫应答状况.研究结果表明,无乳链球菌全菌疫苗能够提高牛蛙的血清抗体水平及总蛋白、免疫球蛋白含量.此外,无乳链球菌全菌苗对牛蛙抗人工感染也具有较好的免疫保护作用,其免疫保护率为67%.因此,将无乳链球菌全菌苗用于牛蛙链球菌病的防治具有广阔的发展前景.%The isolated and identified Streptococcus agalactiae inactivated with 0.4% formaldehyde, made inactivated whole bacteria vaccine with CFA, immunity Bullfrog by injections. By measuring serum agglutinate titer, total protein, the determination of immunoglobulin and immune protection rate, determinate of status of the vaccine immune response. The results showed that all bacteria vaccine can improve the bullfrog serum antibody levels and total protein, immunoglobulin content. In addition, all bacteria vaccine infected bullfrog also has good resistance to the immune protective effects on the immune protection rate. Therefore, there is a potential to apply whole bacteria Streptococcus agalactiae to prevention and cure of Bullfrog suffering with Streptococcus agalactiae.

  11. A comparative study of 2',3'-cyclic-nucleotide 3'-phosphodiesterase in vertebrates: cDNA cloning and amino acid sequences for chicken and bullfrog enzymes.

    Science.gov (United States)

    Kasama-Yoshida, H; Tohyama, Y; Kurihara, T; Sakuma, M; Kojima, H; Tamai, Y

    1997-10-01

    In mammalian brain, two 2',3'-cyclic-nucleotide 3'-phosphodiesterase (EC 3.1.4.37) isoforms, CNP1 and CNP2, are translated, respectively, from the two mRNAs, which have been transcribed and processed by alternative use of the two transcription start points and by differential splicing. In the present study, the cDNAs encoding chicken CNP2 and bullfrog CNP1, respectively, were isolated, and the amino acid sequences of chicken CNP2 and bullfrog CNP1 were deduced. Western blot analysis showed that chicken brain contains a major CNP2-type protein together with a minor unidentified isoform, and bullfrog brain contains only a CNP1-type protein. All available amino acid sequences of vertebrate 2',3'-cyclic-nucleotide 3'-phosphodiesterases were aligned and compared. Three conserved motif sequences were noted: (a) an ATP-binding site near the amino terminus, (b) an isoprenylation site at the carboxyl terminus, and (c) a probable catalytic site resembling the active site of beta-ketoacyl synthase (EC 2.3.1.41). The second and the third motifs are conserved also in goldfish RICH (regeneration-induced 2',3'-cyclic-nucleotide 3'-phosphodiesterase homologue), which has been shown recently to have 2',3'-cyclic-nucleotide 3'-phosphodiesterase activity. The third motif (probably catalytic site) was assigned for the first time in the present report. PMID:9326261

  12. Pond and landscape determinants of Rana dalmatina population sizes in a Romanian rural landscape

    Science.gov (United States)

    Hartel, Tibor; Nemes, Szilárd; Cogălniceanu, Dan; Öllerer, Kinga; Moga, Cosmin Ioan; Lesbarrères, David; Demeter, László

    2009-01-01

    Amphibians are good indicators of human impact, declining steadily worldwide. We explored the relationships between the ponds and nearby landscape parameters and population size of the Agile Frog ( Rana dalmatina), estimated from the number of egg masses, in a cultural landscape within the central section of Târnava Mare Basin, Romania. Forty-three permanent ponds were surveyed in a 2600 km 2 area. The average number of egg masses per pond was 211.13 (SD = 426.41). The egg mass number was significantly and positively related to the emergent aquatic macrophyte cover (its effect peaks at around 50%) and the green connecting corridors between the ponds and forests, and negatively related to the extent of nearby urban areas. The proximity of the forest (positive effect) and the presence of high traffic roads (negative effect) were highly correlated with green corridors and further eliminated from the model due to multicollinearity. Both these variables had significant effects when incorporated in univariate models and multivariate models without green corridors. Since a large part of our study area was currently declared as Natura 2000 site, there is an increased need for management proposals and conservation applications for biodiversity, including amphibians. Rana dalmatina is an important species for monitoring because it is common in the studied area and is suited for short surveys.

  13. Helminth infracommunities of Rana vaillanti brocchi (Anura: Ranidae) in Los Tuxtlas, Veracruz, Mexico.

    Science.gov (United States)

    Paredes-Calderón, Laura; León-Règagnon, Virginia; García-Prieto, Luis

    2004-08-01

    A total of 76 adult individuals of Rana vaillanti were collected in Laguna Escondida, Los Tuxtlas, Veracruz, Mexico, and their helminth infracommunity structure was determined. Among the 21 helminth taxa collected (10 digeneans, 8 nematodes, and 3 acanthocephalans), the digenean Langeronia macrocirra reached the highest prevalence (64.4%), mean abundance (6.6), and mean intensity (10.4), as well as the highest total number of individuals (499). Only 2 frogs were uninfected, the remainder harbored between 1 and 7 helminth species and 1-102 individuals; mean species richness and abundance were 3.49 +/- 0.22 and 16.1 +/- 16.3, respectively. Langeronia macrocirra dominated in 50.6% of the infracommunities, with relatively low Berger-Parker index values (0.56); for this reason, the evenness was high (0.70 +/- 0.31), and consequently, diversity values are the highest recorded to date in species of Rana. However, patterns of helminth infracommunity richness and diversity were similar to those previously observed in amphibians. This structure is attributed to the feeding habits (between 66.7 and 81% of helminth species parasitizing R. vaillanti enter using the food web dynamics) and low vagility (the remainder species infect by host penetration). PMID:15357055

  14. Hybridogeneze u vodních skokanů komplexu Rana esculenta v povodí horní Odry

    Czech Academy of Sciences Publication Activity Database

    Choleva, Lukáš; Kotlík, Petr

    Brno : Herpetologická společnost, 2003. s. 126-127. [Zoologické dny. 13.02.2003-14.02.2003, Brno] Institutional research plan: CEZ:AV0Z5045916 Keywords : rana esculenta Subject RIV: EB - Genetics ; Molecular Biology

  15. Effects of habitat fragmentation and road density on the distribution pattern of the moor frog Rana arvalis.

    NARCIS (Netherlands)

    Vos, C.C.; Chardon, P.

    1998-01-01

    1. The effects of habitat fragmentation on the distribution pattern of the moor frog Rana arvalis were investigated. Also, the possible isolation effects of the road network were taken into account. 2. Indications were found that habitat fragmentation partly explains the distribution pattern of the

  16. Comparison of isometric contractile properties in hindlimb extensor muscles of the frogs Rana pipiens and Bufo marinus: functional correlations with differences in hopping performance.

    Science.gov (United States)

    Chadwell, Brad A; Hartwell, Hadley J; Peters, Susan E

    2002-03-01

    The leopard frog (Rana pipiens) is an excellent jumper that can reach high take-off velocities and accelerations. It is diurnal, using long, explosive jumps to capture prey and escape predators. The marine toad (Bufo marinus) is a cryptic, nocturnal toad, typically using short, slow hops, or sometimes walking, to patrol its feeding area. Typical of frogs with these different locomotor styles, Rana has relatively long hindlimbs and large (by mass) hindlimb extensor muscles compared to Bufo. We studied the isometric contractile properties of their extensor muscles and found differences that correlate with their different hopping performances. At the hip (semimembranosus, SM), knee (peroneus, Per) and ankle (plantaris longus, PL), we found that Rana's muscles tended to produce greater maximum isometric force relative to body mass, although the difference was significant only for PL. This suggests that differences in force capability at the ankle may be more important than at other joints to produce divergent hopping performances. Maximum isometric force scaled with body mass so that the smaller Rana has relatively larger muscles and force differences between species may reflect size differences only. In addition, Rana's muscles exhibited greater passive resistance to elongation, implying more elastic tissue is present, which may amplify force at take-off due to elastic recoil. Rana's muscles also achieved a higher percentage of maximum force at lower stimulus inputs (frequencies and durations) than in Bufo, perhaps amplifying the differences in force available for limb extension during natural stimulation. Twitch contraction and relaxation times tended to be faster in Rana, although variation was great, so that differences were significant only for Per. Fatigability also tended to be greater in Rana muscles, although, again, values reached significance in only one muscle (PL). Thus, in addition to biomechanical effects, differences in hopping performance may also be

  17. Pathophysiology in mountain yellow-legged frogs (Rana muscosa during a chytridiomycosis outbreak.

    Directory of Open Access Journals (Sweden)

    Jamie Voyles

    Full Text Available The disease chytridiomycosis is responsible for declines and extirpations of amphibians worldwide. Chytridiomycosis is caused by a fungal pathogen (Batrachochytrium dendrobatidis that infects amphibian skin. Although we have a basic understanding of the pathophysiology from laboratory experiments, many mechanistic details remain unresolved and it is unknown if disease development is similar in wild amphibian populations. To gain a better understanding of chytridiomycosis pathophysiology in wild amphibian populations, we collected blood biochemistry measurements during an outbreak in mountain yellow-legged frogs (Rana muscosa in the Sierra Nevada Mountains of California. We found that pathogen load is associated with disruptions in fluid and electrolyte balance, yet is not associated with fluctuations acid-base balance. These findings enhance our knowledge of the pathophysiology of this disease and indicate that disease development is consistent across multiple species and in both laboratory and natural conditions. We recommend integrating an understanding of chytridiomycosis pathophysiology with mitigation practices to improve amphibian conservation.

  18. Characteristics of Columbia spotted frog (Rana luteiventris) oviposition sites in northeastern Oregon, USA

    Science.gov (United States)

    Pearl, C.A.; Adams, M.J.; Wente, W.H.

    2007-01-01

    Several western ranid frogs possess a unique strategy of breeding communally over a short temporal window and reusing oviposition sites between years. However, little is published on the characteristics of oviposition sites selected by these explosive breeders. The Columbia spotted frog (Rana luteiventris) is native to northwestern North America and is of conservation concern in the southern portions of its range. As part of a study examining relationships between livestock grazing and R. luteiventris habitat, we assessed characteristics of the species' oviposition sites in 25 fishless ponds in northeastern Oregon. Oviposition sites were generally in shallow water (<25 cm) close to shore and tended to be in the northeastern portion of ponds. Oviposition sites were found more frequently over heavily vegetated substrates and in areas of less substrate slope and shade than random points in littoral zones. We did not quantify temperature differences within ponds, but the patterns we documented are consistent with preferential use of warmer microhabitats for oviposition.

  19. Bone marrow reconstitution of immune responses following irradiation in the leopard frog, Rana pipiens

    International Nuclear Information System (INIS)

    The bone marrow of Rana is an important source of cells capable of maintaining individual viability, responding to Concanavalin A (Con A) and producing PFC against sheep erythrocyte (SRBC) antigens. Frog marrow is more effective than the spleen in maintaining life. Radiation destroys the ability of frogs to respond to SRBC immunization (lack of bone marrow and spleen PFC, serum antibody) and bone marrow/spleen cells to respond to Con A, i.e., bone marrow and spleen contain radiation-sensitive cells. Shielding one hind leg during irradiation leads to reconstitution of bone marrow/spleen PFC responses, antibody synthesis and individual viability. Our results suggest that bone marrow is: a) the source of stem cells, and b) the source of mature T- and B- lymphocytes that can recirculate within the immune system

  20. Columbia spotted frog (Rana luteiventris) in southeastern Oregon: A survey of historical localities, 2009

    Science.gov (United States)

    Pearl, Chistopher A.; Galvan, Stephanie K.; Adams, Michael J.; McCreary, Brome

    2010-01-01

    The Columbia spotted frog (Rana luteiventris) occupies a large range in western North America and is comprised of at least three genetic units. Concern exists regarding the status of the Great Basin populations in Oregon, Idaho, and Nevada. We surveyed target and nearby alternate sites on public lands in southeastern Oregon where there was evidence that Columbia spotted frogs were historically present. We found the species at 59.5 percent (25 of 42) of target or nearby alternate sites. They were in 15 of 23 permanent streams and 8 of 13 intermittent streams. Our surveys do not provide evidence of widespread population losses in our sites. Interpretation of status of Columbia spotted frogs in this study is limited by a lack of precision in some of the historical locations and by our inability to determine if locations where only adults were indicated in the historical record once had breeding populations. Our results support the need for continued investigation of these populations.

  1. Haematoloechus danbrooksi n. sp. (Digenea: Plagiorchioidea) from Rana vaillanti from Los Tuxtlas, Veracruz, Mexico.

    Science.gov (United States)

    León-Règagnon, Virginia; Paredes-Calderón, Erika L

    2002-12-01

    Haematoloechus danbrooksi n. sp. from the lungs of Rana vaillanti in Veracruz state, Mexico, was found. The new species is most similar morphologically to H. medioplexus, H. parviplexus, and H. meridionalis in having a ventral sucker less than half the diameter of the oral sucker. It differs from these species by the extension of the vitellaria, which are shorter in the new species, and in the shape of the tegumental spines, which are blunt in the new species. It differs from all other known species of Haematoloechus in the distribution of the uterine loops that are arranged diagonally and that present several short, extracecal. longitudinal loops in the postacetabular region. The new species shows 1.2% sequence divergence in partial 28S sequence with respect to H. medioplexus, 1.1% with H. parviplexus. and 2.5% with H. meridionalis, sequence divergences complementing the morphological differences. PMID:12537116

  2. Effects of a uranium mine effluent in the early-life stages of Rana perezi Seoane

    International Nuclear Information System (INIS)

    Amphibians have been reported as sensitive organisms whose survival has been impaired by several environmental factors. Nevertheless, sometimes amphibians are found inhabiting extreme environments. Thus, in order to perceive how Iberian green frogs (Rana perezi Seoane) are able to survive in the ponds of a uranium mine (Central Portugal) this study aimed to assess the ecotoxicological effects promoted by the mine effluent in the early-life stages of this species. To attain this objective, eggs (collected in a nearby reference river) and laboratory hatching larvae were exposed during 96 h to different dilutions of the effluent. All the effects on the hatch success were recorded. The highest concentration of the effluent produced a significant decrease in body length of larvae, as well as a decrease in stimulus reactions and an increase in pigmentation along with tail deformities. A recovery assay showed an increased bioaccumulation of metals, uranium included, resulting from increased effluent exposure

  3. [Quantitative estimation of area parameters (with representatives of genus rana as a case study)].

    Science.gov (United States)

    Puzachenko, Iu G; Kuz'min, S L; Sandlerskiĭ, R B

    2011-01-01

    A quantitative method of species "point" area analysis is considered that provides the interpolation of species distribution to the whole territory on the basis of its relationships with climatic and relief variables. It is shown that application of standart statistical interpolation techniques is incorrect. The proposed approach is based on interpolation onto the whole territory the species-specific relations with environmental variables detected in single "points". The basic method for the task proves to be the factor analysis. Within the scope of the study, we have considered the methods for quantitative representation of species relationships with climatic and relief variables. The analysis efficiency is demonstrated by an example of three species of brown frogs: Rana temporaria, R. arvalis u R. amurensis. PMID:22121573

  4. Acute and chronic sensitivity, avoidance behavior and sensitive life stages of bullfrog tadpoles exposed to the biopesticide abamectin.

    Science.gov (United States)

    Vasconcelos, Ana M; Daam, Michiel A; Dos Santos, Liliana R A; Sanches, Ana L M; Araújo, Cristiano V M; Espíndola, Evaldo L G

    2016-04-01

    As compared to other aquatic organism groups, relatively few studies have been conducted so far evaluating the toxicity of pesticides to amphibians. This may at least partly be due to the fact that regulations for registering pesticides usually do not require testing amphibians. The sensitivity of amphibians is generally considered to be covered by that based on toxicity tests with other aquatic organisms (e.g. fish) although the impact of a pesticide on amphibians may be very different. In the present study, acute and chronic laboratory tests were conducted to evaluate the acute and chronic toxicity of abamectin (as Vertimec(®) 18EC) to bullfrog (Lithobates catesbeianus) tadpoles. Acute tests were conducted at two tadpole stages (Gosner stage 21G and 25G) and avoidance tests were also conducted with stage Gosner stage 21G tadpoles. Calculated acute toxicity values were greater than those reported for standard fish test species, hence supporting the use of fish toxicity data as surrogates for amphibians in acute risk assessments. Given the limited number and extent of available amphibian toxicity studies, however, research needs to increase our understanding of pesticide toxicity to amphibians are discussed. PMID:26758616

  5. Calbindin and parvalbumin are early markers of non-mitotically regenerating hair cells in the bullfrog vestibular otolith organs

    Science.gov (United States)

    Steyger, P. S.; Burton, M.; Hawkins, J. R.; Schuff, N. R.; Baird, R. A.

    1997-01-01

    Earlier studies have demonstrated hair cell regeneration in the absence of cell proliferation, and suggested that supporting cells could phenotypically convert into hair cells following hair cell loss. Because calcium-binding proteins are involved in gene up-regulation, cell growth, and cell differentiation, we wished to determine if these proteins were up-regulated in scar formations and regenerating hair cells following gentamicin treatment. Calbindin and parvalbumin immunolabeling was examined in control or gentamicin-treated (GT) bullfrog saccular and utricular explants cultured for 3 days in amphibian culture medium or amphibian culture medium supplemented with aphidicolin, a blocker of nuclear DNA replication in eukaryotic cells. In control cultures, calbindin and parvalbumin immunolabeled the hair bundles and, less intensely, the cell bodies of mature hair cells. In GT or mitotically-blocked GT (MBGT) cultures, calbindin and parvalbumin immunolabeling was also seen in the hair bundles, cuticular plates, and cell bodies of hair cells with immature hair bundles. Thus, these antigens were useful markers for both normal and regenerating hair cells. Supporting cell immunolabeling was not seen in control cultures nor in the majority of supporting cells in GT cultures. In MBGT cultures, calbindin and parvalbumin immunolabeling was up-regulated in the cytosol of single supporting cells participating in scar formations and in supporting cells with hair cell-like characteristics. These data provide further evidence that non-mitotic hair cell regeneration in cultures can be accomplished by the conversion of supporting cells into hair cells.

  6. Comparative microhabitat characteristics at oviposition sites of the California red-legged frog (Rana draytonii)

    Science.gov (United States)

    Alvarez, Jeff A.; Cook, David G.; Yee, Julie L.; van Hattem, Michael G.; Fong, Darren R.; Fisher, Robert N.

    2013-01-01

    We studied the microhabitat characteristics of 747 egg masses of the federally-threatened Rana draytonii (California red-legged frog) at eight sites in California. our study showed that a broad range of aquatic habitats are utilized by ovipositing R. draytonii, including sites with perennial and ephemeral water sources, natural and constructed wetlands, lentic and lotic hydrology, and sites surrounded by protected lands and nested within modified urban areas. We recorded 45 different egg mass attachment types, although the use of only a few types was common at each site. These attachment types ranged from branches and roots of riparian trees, emergent and submergent wetland vegetation, flooded upland grassland/ruderal vegetation, and debris. eggs were deposited in relatively shallow water (mean 39.7 cm) when compared to maximum site depths. We found that most frogs in artificial pond, natural creek, and artificial channel habitats deposited egg masses within one meter of the shore, while egg masses in a seasonal marsh averaged 27.3 m from the shore due to extensive emergent vegetation. Rana draytonii appeared to delay breeding in lotic habitats and in more inland sites compared to lentic habitats and coastal sites. eggs occurred as early as mid-december at a coastal artificial pond and as late as mid-April in an inland natural creek. We speculate that this delay in breeding may represent a method of avoiding high-flow events and/or freezing temperatures. Understanding the factors related to the reproductive needs of this species can contribute to creating, managing, or preserving appropriate habitat, and promoting species recovery.

  7. Aeromonas hydrophila subsp. ranae subsp. nov., isolated from septicaemic farmed frogs in Thailand.

    Science.gov (United States)

    Huys, Geert; Pearson, Marianne; Kämpfer, Peter; Denys, Rik; Cnockaert, Margo; Inglis, Valerie; Swings, Jean

    2003-05-01

    A group of seven sucrose-negative Aeromonas strains (referred to as group Au) isolated from the internal organs of septicaemic farmed frogs (Rana rugulosa) in Thailand was subjected to a polyphasic taxonomic study including fluorescent amplified fragment length polymorphism (FAFLP) and ERIC-PCR fingerprinting, 16S rDNA sequencing, microplate DNA-DNA hybridizations and extensive phenotypic characterization. Comparison of FAFLP and ERIC-PCR fingerprints indicated that the group Au isolates belonged to the species Aeromonas hydrophila DNA hybridization group (HG) 1 in which they represent a genotypic subgroup closely affiliated to A. hydrophila subsp. hydrophila and subsp. dhakensis. One representative of the Au group exhibited > or = 99.0% 16S rDNA sequence similarity with the type strains of the two A. hydrophila subspecies. DNA-DNA hybridization with type and reference strains of all known Aeromonas taxa revealed that the Au group represented a homogeneous taxon that exhibited the highest relatedness with members of the two A. hydrophila subspecies, ranging from 75 to 93%. Phenotypic characterization on the basis of 152 features further revealed that the Au group isolates differed from A. hydrophila subsp. hydrophila or subsp. dhakensis in a total of 13 biochemical properties. Of these, assimilation of L-glycine and isobutyrate as sole carbon source, acid production from salicin and D-sucrose, and aesculin hydrolysis were of diagnostic value. From the results of this study, it can be concluded that the Aeromonas frog isolates of the Au group represent a new subspecies of A. hydrophila, for which the name Aeromonas hydrophila subsp. ranae subsp. nov. is proposed. Its type strain is Au-1D12(T) (=LMG 19707(T) = CCUG 46211(T)). PMID:12807217

  8. A skeletochronological study of growth, longevity, and age at sexual maturity in a population of Rana latastei (Amphibia, Anura)

    Indian Academy of Sciences (India)

    Fabio M Guarino; Silvia Lunardi; Michela Carlomagno; Stefano Mazzotti

    2003-12-01

    Longevity and age at sexual maturity in an Italian population of Rana latastei were studied by skeletochronology performed on the phalanges. Frogs collected in 1998 and 1999 by drift fences and pitfall traps were marked by toe-clipping. After marking, individuals were released and the cut phalanges were processed for skeletochronological analysis. The maximum age so far recorded was 3 years in males and 4 years in females. The smallest male and female that were sexually mature on the basis of histological analysis of the gonads were 36 and 35 mm snout vent length (SVL), respectively. In both sexes, most individuals were estimated to breed shortly after emergence from their first overwintering. Among the European Brown Frogs, Rana latastei appears to be one of the shortest-lived and one of the first to reach sexual maturity.

  9. Biospectroscopy reveals the effect of varying water quality on tadpole tissues of the common frog (Rana temporaria)

    OpenAIRE

    Strong, Becky; Halsall, Crispin James; Ferenčík, Martin; Jones, Kevin Christopher; Shore, Richard Francis; Martin, Francis Luke

    2016-01-01

    Amphibians are undergoing large population declines in many regions around the world. As environmental pollution from both agricultural and urban sources has been implicated in such declines, there is a need for a biomonitoring approach to study potential impacts on this vulnerable class of organism. This study assessed the use of infrared (IR) spectroscopy as a tool to detect changes in several tissues (liver, muscle, kidney, heart and skin) of late-stage common frog (Rana temporaria) tadpol...

  10. Infestación por esparganos en ranas del genero Pristimantis (Anura, Strabomantidae del Perú

    Directory of Open Access Journals (Sweden)

    Luis A. Gomez-Puerta

    2011-05-01

    Full Text Available En el presente estudio, reportamos el parasitismo por esparganos del cestode Spirometra sp. en los anfibios: Pristimantis nephophilus y Pristimantis rhodostichus, provenientes del departamento de San Martin, Perú. Tres estructuras filiformes localizadas a nivel subcutáneo, fueron colectadas e identificadas como esparganos. El hallazgo de este metacestode constituye el primer registro en anfibios del Perú y demuestra que las ranas P. nephophilus y P. rhodostichus son nuevos hospederos intermediarios para Spirometra sp.

  11. Prevalence of the pathogenic chytrid fungus, Batrachochytrium dendrobatidis, in an endangered population of northern leopard frogs, Rana pipiens

    OpenAIRE

    Govindarajulu Purnima; Houston Barb; Adama Doug; Voordouw Maarten J; Robinson John

    2010-01-01

    Abstract Background Emerging infectious diseases threaten naïve host populations with extinction. Chytridiomycosis, an emerging infectious disease of amphibians, is caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd) and has been linked to global declines in amphibians. Results We monitored the prevalence of Bd for four years in the Northern leopard frog, Rana pipiens, which is critically imperiled in British Columbia (BC), Canada. The prevalence of Bd initially increased and ...

  12. Respiration and hemoglobin function in the giant African bullfrog Pyxicephalus adspersus Tschudi (Anura: Pyxicephalidae) during rest, exercise and dormancy

    DEFF Research Database (Denmark)

    van Aardt, W.J; Weber, Roy E.

    2010-01-01

    dormancy in soil without forming cocoons. With virtually no information available on the associated respiratory adaptations, we measured oxygen consumption rates of resting and exercising bullfrogs together with haematological and gas-binding properties of blood and haemoglobin (Hb) solutions from non......-dormant frogs and cocoon-less dormant frogs. Treadmill (0.054 ms-1) exercising frogs consumed nearly seven times more oxygen than resting individuals (8.45 and 1.25 mmol O2 kg-1h-1, respectively). During a six-month dormancy period Pyxicephalus lost an average of 13.7% of its body mass, while plasma osmotic...

  13. Mountain Yellow-legged Frogs (Rana muscosa) did not Produce Detectable Antibodies in Immunization Experiments with Batrachochytrium dendrobatidis.

    Science.gov (United States)

    Poorten, Thomas J; Stice-Kishiyama, Mary J; Briggs, Cheryl J; Rosenblum, Erica Bree

    2016-01-01

    Chytridiomycosis is a devastating infectious disease of amphibians caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). A growing number of studies have examined the role of amphibian adaptive immunity in response to this pathogen, with varying degrees of immune activation reported. Here we present immunologic data for the mountain yellow-legged frog, Rana muscosa, and the Sierra Nevada yellow-legged frog, Rana sierrae, which are two endangered and ecologically important species experiencing Bd-inflicted declines. Previous studies on these species that examined transcriptional response during Bd infection, and the effective of immunization, provided little evidence of immune activation to Bd. However, the studies did not directly assay immune effectors in the frog hosts. We performed experiments to examine antibody production, which is a hallmark of systemic adaptive immune activation. We used controlled laboratory experiments and enzyme-linked immunosorbent assays to examine the antibody response to Bd immunization and live Bd exposure. Rana muscosa and R. sierrae individuals did not produce detectable antibodies with the capacity to bind to denatured Bd antigens under our experimental conditions. While we cannot rule out antibody response to Bd in these species, our results suggest weak, poor, or inefficient production of antibodies to denatured Bd antigens. Our findings are consistent with susceptibility to chytridiomycosis in these species and suggest additional work is needed to characterize the potential for adaptive immunity. PMID:26540180

  14. Radiocesium accumulation in the anuran frog, Rana tagoi tagoi, in forest ecosystems after the Fukushima Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Amphibians are key components in forest food webs. When examining radioactive contamination in anurans, it is important to understand how radiocesium transfer occurs from lower to higher trophic levels in forest ecosystems. We investigated the activity concentration of radiocesium (134Cs and 137Cs) in Tago's brown frog (Rana tagoi tagoi) captured on the forest floor approximately 2.5 years after the Fukushima Nuclear Power Plant (FNPP) accident. We collected 66 R. tagoi tagoi at different distances from the FNPP. Radiocesium accumulation showed positive correlations with the air radiation dose rate and litter contamination but not with distance from the FNPP. Whole-body radioactivity showed no correlation with body mass or length. Our results suggest that differences in the available food items result in large variability in individual contamination. Contamination level monitoring in terrestrial and aquatic amphibian is necessary for clarifying the processes and mechanisms of radiocesium transfer through forest food webs. - Highlights: • Radiocesium level in Rana tagoi tagoi from forests near Fukushima was assessed. • Radiocesium accumulation was related to air dose rate and litter contamination. • Differences in dietary intake might lead to variability in individual contamination. • Transfer of radiocesium among trophic levels can occur via anurans. - Rana tagoi tagoi accumulates radiocesium in forest floor habitats near Fukushima

  15. Bioaccumulation of macro- and trace elements by European frogbit (Hydrocharis morsus-ranae L.) in relation to environmental pollution.

    Science.gov (United States)

    Polechońska, Ludmiła; Samecka-Cymerman, Aleksandra

    2016-02-01

    The aim of present study was to investigate the level of trace metals and macroelements in Hydrocharis morsus-ranae collected from regions differing in the degree and type of pollution. Concentrations of 17 macro- and microelements were determined in roots and shoots of European frogbit as well as in water and bottom sediments from 30 study sites. Plants differed in concentrations of elements and bioaccumulation capacity depending on the characteristics of dominant anthropogenic activities in the vicinity of the sampling site. Shoots of H. morsus-ranae growing in the vicinity of organic chemistry plants and automotive industry contained particularly high levels of Cd, Co, and S. Plants from area close to heat and power plant, former ferrochrome industry and new highway, were distinguished by the highest concentrations of Cr, Cu, and Pb. European frogbit from both these regions contained more Fe, Hg, Mn, Ni, and Zn than plants from agricultural and recreational areas. The concentrations of alkali metals and Co, Fe, and N in H. morsus-ranae were elevated in relation to the natural content in macrophytes irrespectively to their content in the environment. Based on the values of Bioaccumulation and Translocation Factors, European frogbit is an accumulator for Co, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn and a good candidate for phytoremediation of water polluted with Co, Cu, Hg, K, Mn, and Ni. The amount of Co and Mn removed from water and accumulated in the plant biomass during the vegetation season was considerably high. PMID:26490926

  16. Comparative transduction mechanisms of hair cells in the bullfrog uticulus. 2: Sensitivity and response dynamics to hair bundle displacement

    Science.gov (United States)

    Baird, Richard A.

    1994-01-01

    The present study was motivated by an interest in seeing whether hair cell types in the bullfrog utriculus might differ in their voltage responses to hair bundle displacement. Particular interest was in assessing the contributions of two factors to the responses of utricular hair cells. First, interest in examining the effect of hair bundle morphology on the sensitivity of hair cells to natural stimulation was motivated by the observation that vestibular hair cells, unlike many auditory hair cells, are not free-standing but rather linked to an accessory cupular or otolithic membrane via the tip of their kinocilium. Interest also laid in examining the contribution, if any, of adaptation to the response properties of utricular hair cells. Hair cells in auditory and vibratory inner ear endorgans adapt to maintained displacements of their hair bundles, sharply limiting their low frequency sensitivity. This adaptation is mediated by a shift in the displacement-response curve (DRC) of the hair cell along the displacement axis. Observations suggest that the adaptation process occurs within the hair bundle and precedes mechanoelectric transduction. Recent observations of time-dependent changes in hair bundle stiffness are consistent with this conclusion. Adaptation would be expected to be most useful in inner ear endorgans in which hair cells are subject to large static displacements that could potentially saturate their instantaneous response and compromise their sensitivity to high frequency stimulation. The adaptation process also permits hair cells to maintain their sensory hair bundle in the most sensitive portion of their DRC. In vestibular otolith organs in which static sensitivity is desirable, any adaptation process in the hair cells may be undesirable. The rate and extent of the decline of the voltage responses was measured of utricular hair cells to step and sinusoidal hair bundle displacements. Then for similar resting potentials and response amplitudes, the

  17. Biodiversity and productivity of Rana Patap Sagar lake a thermo-ecological study

    International Nuclear Information System (INIS)

    Rana Pratap Sagar (RPS) in Rajasthan, is a man made fresh water reservoir and is balancing between Gandhi Sagar on upstream and Jawahar sagar on its down stream. On its eastern bank there exists Rawatbhata Site, comprising of multi -nuclear facilities. There are four PHWR units of Rajasthan Atomic Power Station (RAPS) which are in operations, two are under construction and another two are under advanced stage of planning. In addition to nuclear power plants the Site also houses a Heavy Water Plant and other allied facilities such as cobalt facility and waste management facilities. RAPS draws water from RPS lake through a 300 m long conduit pipe located at lake bottom about 20 m below the surface. Duly treated low level radioactive liquid effluents from RAPS facilities are injected to the warmed condenser outlet and then allowed to discharge to RPS in a controlled manner. The warm water is likely to remain at the surface and get mixed with lake water and cooled due to dilutions, evaporation from lake surface and wind currents. The heat release to the RPS lake through condenser outlet may effect the microbiological and water quality parameters, planktonic biodiversity, fish productivity etc. and thus it is imperative to conduct the thermal ecological study to assess the extent of maturation of the water body to identify its present trophic status in terms of eutrophication. This presentation gives the details of thermal ecological studies carried out at Rana Pratap Sagar lake during 2002-2004 under DAE-BRNS project.. The study includes monitoring of several water quality parameters, biological and bacterial parameters and data on thermal stratification in respect of RPS reservoir. The data so obtained were subjected to statistical analysis. The probabilistic and possibilistic approaches have been applied to evaluate ecological risk. The study reveals that there is no adverse effect on RPS water quality owing to receive the warmed effluents from RAPS. Furthermore, it

  18. Hepatic effects of the clomazone herbicide in both its free form and associated with chitosan-alginate nanoparticles in bullfrog tadpoles.

    Science.gov (United States)

    de Oliveira, Cristiane Ronchi; Fraceto, Leonardo Fernandes; Rizzi, Gisele Miglioranza; Salla, Raquel Fernanda; Abdalla, Fábio Camargo; Costa, Monica Jones; Silva-Zacarin, Elaine Cristina Mathias

    2016-04-01

    The use of agrochemicals in agriculture is intense and most of them could be carried out to aquatic environment. Nevertheless, there are only few studies that assess the effects of these xenobiotics on amphibians. Clomazone is an herbicide widely used in rice fields, where amphibian species live. Thus, those species may be threatened by non-target exposure. However, nanoparticles are being developed to be used as a carrier system for the agrochemicals. Such nanoparticles release the herbicide in a modified way, and are considered to be more efficient and less harmful to the environment. The aim of this study was to comparatively evaluate the effect of clomazone in its free form and associated with nanoparticles, in the liver of bullfrog tadpoles (Lithobates catesbeianus) when submitted to acute exposure for 96 h. According to semi-quantitative analysis, there was an increase in the frequency of melanomacrophage centres, in the accumulation of eosinophils and in lipidosis in the liver of experimental groups exposed to clomazone - in its free form and associated with nanoparticles - in comparison with the control group, and the nanotoxicity of chitosan-alginate nanoparticles. The increase of melanomacrophage centres in all exposed groups was significant (P herbicide and nanoparticles triggered hepatic responses. Moreover, these results provided important data about the effect of the clomazone herbicide and organic nanoparticles, which act as carriers of agrochemicals, on the bullfrog tadpole liver. PMID:26874058

  19. Mercury pollution in Rana Chensinensis in Weisha River reach, in the upstream region of Songhua River

    Institute of Scientific and Technical Information of China (English)

    WANG Ning; ZHU Yanming; SHENG Lianxi; MENG Dan

    2005-01-01

    Twice a year continuous samples of Rana Chensinensis and sediments have been collected near gold mine in the upstream region of Songhua River from 2000 to 2002, for analyzing the total mercury (THg), methylmercury (MeHg) concentration and correlation in sediments, muscles, livers of the frog. The study indicates that THg and MeHg concentrations in polluted samples near the gold mine are higher than those in unpolluted ones. THg and MeHg concentrations are higher in autumn, in female, and in livers than those in spring, in male, in muscles respectively. The order of concentration degree in the frog organizations is as follows: liver>muscle>ovum>Fallopian tube. MeHg is the main form of mercury (Hg) existing in autumn, while inorganic Hg is in spring. There is no distinct difference of CMeHg/CTHg between male and female, livers and muscles. The correlation between MeHg concentrations in the river sediments and in the frog's livers and muscles are significant, which is related to disorderly discharge of Hg.

  20. Comparative toxicity of chlorpyrifos, diazinon, malathion and their oxon derivatives to larval Rana boylii

    International Nuclear Information System (INIS)

    Organophosphorus pesticides (OPs) are ubiquitous in the environment and are highly toxic to amphibians. They deactivate cholinesterase, resulting in neurological dysfunction. Most chemicals in this group require oxidative desulfuration to achieve their greatest cholinesterase-inhibiting potencies. Oxon derivatives are formed within liver cells but also by bacterial decay of parental pesticides. This study examines the toxicity of chlorpyrifos, malathion and diazinon and their oxons on the foothill yellow-legged frog (Rana boylii). R. boylii is exposed to agricultural pesticides in the California Central Valley. Median lethal concentrations of the parental forms during a 96 h exposure were 3.00 mg/L (24 h) for chlorpyrifos, 2.14 mg/L for malathion and 7.49 mg/L for diazinon. Corresponding oxons were 10 to 100 times more toxic than their parental forms. We conclude that environmental concentrations of these pesticides can be harmful to R. boylii populations. - Laboratory tests on the toxicity of OP insecticides and their oxons suggest that they may be acutely lethal to amphibians at ecologically relevant concentrations

  1. Effects of fluoride on development and growth of Rana chensinensis embryos and larvae.

    Science.gov (United States)

    Chai, Lihong; Dong, Suiming; Zhao, Hongfeng; Deng, Hongzhang; Wang, Hongyuan

    2016-04-01

    The present study examined the adverse effects of fluoride exposure on embryos and larvae of Rana chensinensis. Survival, morphological abnormalities, growth and development, time to metamorphosis and size at metamorphic climax of R. chensinensis were examined. Our results showed that embryos malformation occurred in all fluoride treatments. Morphological abnormalities of embryos are characterized by axial flexures, the extrusion of fin axis, edema, and ruffled dorsal and ventral fin. Additionally, 4.1mg F(-)/L and above could significantly inhibit embryos growth and development. On day 15, total length and weight of tadpole were significantly lower in 19.6 and 42.4mg F(-)/L treatments compared to control. However, significant reductions in total length and weight were observed only at 42.4mg F(-)/L on day 30. Moreover, significant metamorphic delay and decrease in the size at metamorphic climax were found in larvae exposed to 42.4mg F(-)/L. Taken together, embryos of R. chensinensis are more vulnerable to fluoride exposure than their tadpoles. Our results suggested that the presence of high concentrations fluoride might increase mortality risk and a reduction in juvenile recruitment in the field by increasing embryos malformation, delaying metamorphosis and decreasing size at metamorphosis. PMID:26745004

  2. Receptor-mediated endocytosis of lysozyme in renal proximal tubules of the frog Rana temporaria

    Directory of Open Access Journals (Sweden)

    E.V. Seliverstova

    2015-04-01

    Full Text Available The mechanism of protein reabsorption in the kidney of lower vertebrates remains insufficiently investigated in spite of raising interest to the amphibian and fish kidneys as a useful model for physiological and pathophysiological examinations. In the present study, we examined the renal tubular uptake and the internalization rote of lysozyme after its intravenous injection in the wintering frog Rana temporaria using immunohisto- and immunocytochemistry and specific markers for some endocytic compartments. The distinct expression of megalin and cubilin in the proximal tubule cells of lysozyme-injected frogs was revealed whereas kidney tissue of control animals showed no positive immunoreactivity. Lysozyme was detected in the apical endocytic compartment of the tubular cells and colocalized with clathrin 10 min after injection. After 20 min, lysozyme was located in the subapical compartment negative to clathrin (endosomes, and intracellular trafficking of lysozyme was coincided with the distribution of megalin and cubilin. However, internalized protein was retained in the endosomes and did not reach lysosomes within 30 min after treatment that may indicate the inhibition of intracellular trafficking in hibernating frogs. For the first time, we provided the evidence that lysozyme is filtered through the glomeruli and absorbed by receptor-mediated clathrin-dependent endocytosis in the frog proximal tubule cells. Thus, the protein uptake in the amphibian mesonephros is mediated by megalin and cubilin that confirms a critical role of endocytic receptors in the renal reabsorption of proteins in amphibians as in mammals.

  3. Spontaneous otoacoustic emissions in the European edible frog (Rana esculenta): spectral details and temperature dependence.

    Science.gov (United States)

    van Dijk, P; Wit, H P; Segenhout, J M

    1989-11-01

    Spontaneous otoacoustic emissions were recorded in 41 ears of 29 European edible frogs (Rana esculenta). Emission frequencies ranged from 450 to 1350 Hz. The distribution of frequencies shows two distinct populations: one above and one below 1 kHz. With one exception, a maximum number of two emissions were recorded per ear, each in a different population. An amplitude distribution of a frog emission was sampled, from which it was concluded that the emission is generated by an active oscillator. The spectral width of an emission ranged from 1 to 200 Hz (average 38 Hz). There was negative correlation between sound pressure level of an emission and spectral width. In 4 frogs the dependence of emission power and frequency on temperature was investigated. An emission could be 'switched on and off' within a few degrees centigrade. At temperatures below the switching interval no emission was recorded; for higher temperatures emission power showed no dependence on temperature. Frequency increased with temperature (Q10 = 1.1 to 1.3). This yields a mismatch with temperature dependence of best frequencies of auditory fibers. The consequences of this mismatch are discussed. PMID:2691473

  4. Widespread occurrence of the chytrid fungus batrachochytrium dendrobatidis on oregon spotted frogs (rana pretiosa)

    Science.gov (United States)

    Pearl, C.A.; Bowerman, J.; Adams, M.J.; Chelgren, N.D.

    2009-01-01

    The pathogen Batrachochytrium dendrobatidis (Bd) has been associated with amphibian declines in multiple continents, including western North America. We investigated Bd prevalence in Oregon spotted frog (Rana pretiosa), a species that has declined across its range in the Pacific Northwest. Polymerase chain reaction analysis of skin swabs indicated that Bd was prevalent within populations (420 of 617 juvenile and adults) and widespread among populations (36 of 36 sites) where we sampled R. pretiosa in Oregon and Washington. We rarely detected Bd in R. pretiosa larvae (2 of 72). Prevalence of Bd in postmetamorphic R. pretiosa was inversely related to frog size. We found support for an interactive effect of elevation and sampling date on Bd: prevalence of Bd generally increased with date, but this effect was more pronounced at lower elevations. We also found evidence that the body condition of juvenile R. pretiosa with Bd decreased after their first winter. Our data indicate that some Oregon spotted frog populations are currently persisting with relatively high Bd prevalence, but the risk posed by Bd is unknown. ?? 2010 International Association for Ecology and Health.

  5. Seasonal Variation in the Hepatoproteome of the Dehydration- and Freeze-Tolerant Wood Frog, Rana sylvatica

    Directory of Open Access Journals (Sweden)

    Jon P. Costanzo

    2011-11-01

    Full Text Available Winter’s advent invokes physiological adjustments that permit temperate ectotherms to cope with stresses such as food shortage, water deprivation, hypoxia, and hypothermia. We used liquid chromatography (LC in combination with tandem mass spectrometry (MS/MS quantitative isobaric (iTRAQ™ peptide mapping to assess variation in the abundance of hepatic proteins in summer- and winter-acclimatized wood frogs (Rana sylvatica, a northerly-distributed species that tolerates extreme dehydration and tissue freezing during hibernation. Thirty-three unique proteins exhibited strong seasonal lability. Livers of winter frogs had relatively high levels of proteins involved in cytoprotection, including heat-shock proteins and an antioxidant, and a reduced abundance of proteins involved in cell proliferation, protein synthesis, and mitochondrial function. They also exhibited altered levels of certain metabolic enzymes that participate in the biochemical reorganization associated with aphagia and reliance on energy reserves, as well as the freezing mobilization and post-thaw recovery of glucose, an important cryoprotective solute in freezing adaptation.

  6. California red-legged frog (Rana draytonii) movement and habitat use: Implications for conservation

    Science.gov (United States)

    Fellers, G.M.; Kleeman, P.M.

    2007-01-01

    Nonbreeding habitats are critically important for Rana draytonii, especially for individuals that breed in temporary bodies of water. We radiotracked 123 frogs to evaluate seasonal habitat use. Individual frogs were continuously tracked for up to 16 months. Some individuals remained at breeding ponds all year, but 66% of female and 25% of male frogs moved to nonbreeding areas, even when the breeding site retained water. Frogs at our main study site moved 150 m (median), roughly the distance to the nearest suitable nonbreeding area. The greatest straight-line distance traveled was 1.4 km, although the presumed distance traveled was 2.8 km. Females were more likely than males to move from permanent ponds (38% of females, 16% of males), but among dispersing frogs, males and females did not differ in distance moved. Some frogs left breeding sites shortly after oviposition (median = 12 days for females, 42.5 days for males), but many individuals remained until the site was nearly dry. Fog provided moisture for dispersal or migration throughout the summer. Our data demonstrate that maintaining populations of pond-breeding amphibians requires that all essential habitat components be protected; these include (1) breeding habitat, (2) nonbreeding habitat, and (3) migration corridors. In addition, a buffer is needed around all three areas to ensure that outside activities do not degrade any of the three habitat components. Copyright 2007 Society for the Study of Amphibians and Reptiles.

  7. BIOMETRIC STUDY TO RANA RIDIBUNDA FROG SPECIES NEARNESS TO TIMISOARA LOCALITY

    Directory of Open Access Journals (Sweden)

    M. BURA

    2013-12-01

    Full Text Available Speciality literature provides little informations regarding Rana ridibunda frogbiometry. For supply this gap we studied the size and weight of 54 frogs sampled fromnearby Timişoara area ponds.The mean body lenght was 8,08 ± 0,54 cm for the females and respectively 6,17 ± 0,45cm for the males. Before evisceration on a par females weighted 62,28 ± 12,87 g andthe males 22,46 ± 5,3 g whereas after this action the carcase weighted 43,89 ± 8,91 gin the case of females and respectively 18,45 ± 4,42 g in the case of male lake frog. Themean leg lenght measured 12,59 ± 0,68 cm for female frogs and 9,78 ± 0,66 cm in thecase of male frogs. The hind stylopodium was estimated on a par as 13,23 ± 2,57 g forfemales and 5,33 ± 1,26 g for the males.

  8. Comparative toxicity of chlorpyrifos, diazinon, malathion and their oxon derivatives to larval Rana boylii

    Energy Technology Data Exchange (ETDEWEB)

    Sparling, D.W. [Cooperative Wildlife Research Laboratory, Department of Zoology and Center for Ecology, Southern Illinois University, LS II, MS6504, Carbondale, IL 62901 (United States)]. E-mail: dsparl@siu.edu; Fellers, G. [Western Ecology Research Center, U.S. Geological Survey, Point Reyes National Seashore, Point Reyes, CA 94956 (United States)

    2007-06-15

    Organophosphorus pesticides (OPs) are ubiquitous in the environment and are highly toxic to amphibians. They deactivate cholinesterase, resulting in neurological dysfunction. Most chemicals in this group require oxidative desulfuration to achieve their greatest cholinesterase-inhibiting potencies. Oxon derivatives are formed within liver cells but also by bacterial decay of parental pesticides. This study examines the toxicity of chlorpyrifos, malathion and diazinon and their oxons on the foothill yellow-legged frog (Rana boylii). R. boylii is exposed to agricultural pesticides in the California Central Valley. Median lethal concentrations of the parental forms during a 96 h exposure were 3.00 mg/L (24 h) for chlorpyrifos, 2.14 mg/L for malathion and 7.49 mg/L for diazinon. Corresponding oxons were 10 to 100 times more toxic than their parental forms. We conclude that environmental concentrations of these pesticides can be harmful to R. boylii populations. - Laboratory tests on the toxicity of OP insecticides and their oxons suggest that they may be acutely lethal to amphibians at ecologically relevant concentrations.

  9. genotoxicity of the pesticide dichlorvos and herbicide butachlor on rana zhenhaiensis tadpoles

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    genotoxicity of dichlorvos and butachlor on erythrocytes of rana zhenhaiensis tadpoles was investigated by the alkaline single-cell gel electrophoresis assay or comet assay.tadpoles were treated for 24 h in the laboratory with different concentrations of the testing agents,2.256,4.512,6.768,9.024,11.280 mg/l for dichlorvos and 0.292,0.584,0.876,1.168,1.460 mg/l for butachlor,to use the comet assay to test for the significance of dosage responsiveness to an increase in dna damage,as measured by the mean dna tail length-to-width ratio.the concentrations of 4.512 mg/l dichlorvos and 0.876 mg/l butachlor resulted in highly significant increases in dna damage of the tadpoles.there were linear correlations between the mean dna tail length-to-width ratio and the concentrations of the two test substances.our results showed that the two commonly used agricultural chemicals caused dose dependent dna damage of amphibians,and that comet assay might be a useful tool for measuring dna damage of tadpoles exposed in the field.

  10. Helicopter-borne magnetic, electromagnetic and radiometric geophysical survey in the Storforshei area, Rana, Nordland

    International Nuclear Information System (INIS)

    NGU conducted an airborne geophysical survey in Mo i Rana area in July 2012. This report describes and documents the aquisition, processing and visualization of recorded datasets. The geophysical survey results reported herein are 1414 line km. The Geotech Ltd. Hummingbird frequency domain system supplemented by optically pumped cesium magnetometer and 1024 channels RSX-5 spectrometer was used for data aquisition. The survey was flown with 100 m line spacing, line direction of 180 deg North-South (in the west) and 150 deg NorthWest-SouthEast (in the east) with the average speed 96 km/h. The average terrain clearance of the bird was 55 m. Collected data were processed by AR GeoConsulting using Geosoft Oasis Montaj software. Raw total magnetic field data were corrected for diurnal variation and levelled using standard micro levelling algorithm. EM data were filtered and levelled using both automated and manual levelling procedure. Apparent resistivity was calculated from in-phase and quadrature data for each of the five frequencies separately using a homogeneous half space model. Apparent resistivity dataset was levelled and filtered. Radiometric data were processed using standard procedures recommended by International Atomic Energy Association (IAEA). All data were gridded with the cell size of 25 m and presented as shaded relief maps at the scale of 1:25 000.(Author)

  11. Data on the isolation of immunoglobulin from the serum of the green frog: Rana esculenta

    Directory of Open Access Journals (Sweden)

    Stošić Svetlana

    2006-01-01

    Full Text Available Even though the green frog (Rana esculenta is often used as an experimental model for further studies of physiological laws, little is still known about its serum proteins and their role in immunity. Its serum proteins have been studied quite extensively, as when they are taken up into the organism of another animal they represent antigens themselves. In this work, an attempt was made to isolate some frog serum proteins and to investigate the electrophoretic qualities of the isolated components (electrophoresis on agar gel and immunoelectrophoresis. IgG was isolated using the same procedure applied for human sera and one of the components found in the beta globulin zone was isolated from frog serum by the same procedure. Immunoelectrophoretic analysis, carried out with the full antiserum of a rabbit, obtained by immunization of the rabbit with the frog serum, showed that the isolated component was pure. The obtained results confirm the fact that there are no slow gamma globulins in the frog serum and point out that this procedure, used for isolating human IgG class, is also suitable for isolating one protein component from the serum of the frog, which has the electrophoretic speed of beta globulin and which may represent one category of frog immunoglobulins.

  12. Molecular cloning and expression patterns of the Vasa gene from Rana nigromaculata (Amphibia: Anura

    Directory of Open Access Journals (Sweden)

    Rui Jia

    2009-06-01

    Full Text Available The Vasa protein is a member of the DEAD (Asp-Glu-Alu-Asp box family of ATP-dependent RNA helicases. The Vasa gene is specifically expressed in germ-line cells of many metazoans and is known to play a critical role in gametogenesis and reproductive regulation. In this paper, we isolate the full length cDNA sequence of the Vasa gene from the frog Rana nigromaculata Hallowell, 1861. The open reading frame (ORF encoding 398 amino acid residues has nine conserved motifs. According to the similarities at the amino acid sequenceythe phylogenetic analysis of Vasa gene was consistent with the evolution relationships from chordates to mammals. Furthermore, the expression pattern analysis of RnVasa mRNA, using the technique of Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR, showed a high level of transcripts in testis, ovary and kidney, whereas little to no signal was detected in other tissues, which suggests that it may play a role during gametogenesis.

  13. Preferred Feeding Sites and Prey of the Adult Gold-spotted Pond Frog, Rana plancyi chosenica

    Directory of Open Access Journals (Sweden)

    Eom, Junho1

    2007-11-01

    Full Text Available To determine the feeding sites preferred by adult gold-spotted pond frogs, Rana plancyi chosenica,and the foods that induce favorable growth of the frogs in the laboratory, we conducted two separate experimentsbetween 27 May and 12 July 2007 in a vivarium. In the first experiment, we counted the number of cricketseaten by four gold-spotted pond frogs in a 60 min period at four different feeding sites within the experimentalarenas: on the water surface, at the edge of a pond, and at two terrestrial sites. Adult gold-spotted pond frogsate more crickets on the water surface and at the edge of the pond than the terrestrial sites. In the secondexperiment, we measured the growth of SVL (snout-vent length and body mass of adult gold-spotted pond frogsfed crickets, mealworms, maggots, or earthworms in individual experimental boxes over a one month period. TheSVL and body mass of the adult gold-spotted pond frogs fed crickets, mealworms, or maggots were greater thanthose of the frogs that were fed earthworms. These results indicate that providing crickets, mealworms, ormaggots on the water or at the edge of a pond should induce favorable growth of captive-reared adult goldspottedpond frogs.

  14. Rana grylio virus TK and DUT gene locus could be simultaneously used for foreign gene expression.

    Science.gov (United States)

    Huang, Xing; Fang, Jin; Chen, Zhongyuan; Zhang, Qiya

    2016-03-01

    Ranaviruses (family Iridoviridae, genus Ranavirus) have been recognized as emerging infectious pathogens and caused a great loss to the global biodiversity. Thymidine kinase (TK) and deoxyuridine triphosphatase (dUTPase, DUT, encoded by ORF 67R) are ubiquitous, existing in iridoviruses and other organisms. Previous studies showed that TK and DUT could be individually knocked out without impeding viral replication. In this study, we tried to insert two fluorescence genes into the above loci. We started with Δ67R-RGV, a recently generated recombinant Rana grylio virus (RGV) with the whole DUT replaced by enhanced green fluorescence protein (EGFP) gene. Then, a red fluorescence protein (RFP) gene initiated by RGV immediate-early (IE) ICP18 gene promoter was inserted into TK locus through homologous recombination. A novel recombinant virus, ΔDUT, TK-RGV, was generated by nine successive rounds of plaque isolation using RFP selection. All of the plaques produced by this recombinant virus could emit both green and red fluorescence. Furthermore, one-step and multiple-step growth curves of ΔDUT, TK-RGV were similar to those of wt-RGV and Δ67R-RGV. In conclusion, a novel dual-fluorescence labeled recombinant iridovirus in which DUT and TK gene locus were simultaneously used for foreign gene expression was constructed. PMID:26806670

  15. First isolation and identification of Elizabethkingia meningoseptica from cultured tiger frog, Rana tigerina rugulosa.

    Science.gov (United States)

    Xie, Zhen-Yu; Zhou, Yong-Can; Wang, Shi-Feng; Mei, Bing; Xu, Xian-Dong; Wen, Wan-Yao; Feng, Yong-Qin

    2009-07-01

    Elizabethkingia meningoseptica has been recognised as an occasional but serious opportunistic bacterial pathogen to human beings. Recently, it was frequently isolated from tiger frog, Rana tigerina rugulosa, with cataract disease, which is the most common disease of unknown aetiology of frogs in Hainan, China. The purpose of this study was to identify and characterise the bacterial strains isolated from the recent outbreaks of cataract disease in farmed tiger frog in Hainan, China, and to evaluate their pathogenicity to the frog and their sensitivity to 20 chemotherapeutic agents. The 16S rRNA gene sequences of strains W0701 (1478bp), W0702 (1477bp) and W0703 (1478bp) showed 98.6-98.7% similarity with the sequence of E. meningoseptica type strain (ATCC 13253) and 99.9-100% similarity with that of E. meningoseptica NTU 870424-IL. Six strains (W0701-W0706) were selected to represent 24 isolates retrieved from six moribund frogs. The morphological, physiological and biochemical characteristics of the six representative isolates were consistent with those of E. meningoseptica strains. The organisms were only susceptible to vancomycin and moderately susceptible to cefoperazone among the 20 investigated chemotherapeutic agents. Virulence test with strain W0702 was conducted and pathogenicity (by intramuscular injection) was demonstrated in the tiger frog. In conclusion, 24 isolates obtained from frogs with cataract disease were the E. meningoseptica strains highly pathogenic to tiger frog, and this is the first report of E. meningoseptica as a pathogen for tiger frog. PMID:19327918

  16. Extraction and Characterization of Undenatured Type Ⅰ Collagen from the Bullfrog Skin%牛蛙皮中未变性Ⅰ型胶原蛋白的提取及性能表征

    Institute of Scientific and Technical Information of China (English)

    杨波; 李国英

    2012-01-01

    Distribution pattern of collagen in the bullfrog skin was observed in this study. Acid - soluble collagen (ASC) and pepsin - soluble collagen ( PSG) were extracted from the bullfrog skin by acetic acid and acetic acid - pepsin f respectively. Results of the studies on the physicochemical properties of ASC and PSC indicated that the collagen gained was undenatured type I collagen. Ultraviolet absorption spectra showed that the absorption peak of bullfrog collagen was 233 nm. The denaturation temperature of ASC (32.60 ℃.) was higher than that of PSC (32.22 ℃,) , whereas the isoelectric point of ASC(6.79) was lower than that of PSC(7. 15). The imino acid content of collagen from bullfrog skin was lower than that from calf skin and higher than that from fish skin. Moreover, cysteine, which was not existed in calf skin collagen, was observed in bullfrog skin collagen.%观察了胶原蛋白在牛蛙皮肤组织中的分布形态.分别采用酸法和酸酶法提取得到酸溶胶原(ASC)和酶溶胶原(PSC).理化性质分析结果表明:所提取得到的胶原为未变性Ⅰ型胶原;紫外吸收峰在233nm处;ASC的变性温度(32.60℃)高于PSC的变性温度(32.22℃),而ASC的等电点(6.79)低于PSC的等电点(7.15);牛蛙皮胶原的氨基酸组分中,亚氨基酸的含量较牛皮的低,较鱼皮的高,同时,牛蛙皮胶原中含有牛皮胶原中没有的半胱氨酸.

  17. Hexadactyly case at a Rana kl. esculenta sample from the north-western part of Romania (Short Notes

    Directory of Open Access Journals (Sweden)

    Istvan SAS

    2006-05-01

    Full Text Available At 17 June 2006, in a habitat close to Gherta Mica locality (47°56'0'' N, 23°14'0'' E, Satu-Mare County, Romania we had found a sample of Rana kl. esculenta which presented hexadactyly at both of its posterior feet. The captured sample of edible frog had fully formed extra (sixth toes, with phalanges (bones. The hexadactyly was perfectly symmetrical at both of the posterior feet. At this individual we did not discovered any other malformations, the biometrical characters situating in the variations limits of the other green frogs from the studied habitat. A symmetric hexadacytly can be a result of atavism.

  18. Hexadactyly case at a Rana kl. esculenta sample from the north-western part of Romania (Short Notes)

    OpenAIRE

    Istvan SAS; Eva-Hajnalka KOVACS

    2006-01-01

    At 17 June 2006, in a habitat close to Gherta Mica locality (47°56'0'' N, 23°14'0'' E, Satu-Mare County, Romania) we had found a sample of Rana kl. esculenta which presented hexadactyly at both of its posterior feet. The captured sample of edible frog had fully formed extra (sixth) toes, with phalanges (bones). The hexadactyly was perfectly symmetrical at both of the posterior feet. At this individual we did not discovered any other malformations, the biometrical characters situating in the v...

  19. Nueva especie de rana del género Pristimantis del grupo lacrimosus (Amphibia: Craugastoridae) del Parque Nacional Sangay, Ecuador

    OpenAIRE

    Diego Batallas R.; Jorge Brito M.

    2014-01-01

    Describimos una nueva especie de rana terrestre del genero Pristimantis de tamaño mediano (LRC en machos desde 22.18 a 25.13 mm) descubierta en los bosques nublados de las estribaciones orientales del Parque Nacional Sangay, al centro oriente de Ecuador, a elevaciones de 2750 m. Asignamos a Pristimantis latericius sp. nov., al grupo Pristimantis lacrimosus, el cual se diferencia del resto de miembros de este grupo por presentar tubérculos prominentes en el parpado superior y una coloración ro...

  20. Rana Dorada: un caminante hacia la extinción (artículo de opinión)

    OpenAIRE

    Nury Natalia Garzón-Aguiar

    2015-01-01

    La extinción animal es un asunto muy amplio que a muchos interesa, algunos ignoran y otros desconocen, este es el tema a tratar en el presente artículo, tomando como ejemplo la rana dardo dorada (Phyllobates terribilis), un hermoso anfibio endémico de Colombia, denominado como el animal más venenoso y como una de las siete maravillas del mundo entre las especies amenazadas de extinción. Perteneciente al Reino ANIMALIA, al fillum de los Cordados, orden Anura y familia Dendrobatidae. En el Géne...

  1. Behavioral Responses of Northern Leopard Frogs (Rana pipiens to Roads and Traffic: Implications for Population Persistence

    Directory of Open Access Journals (Sweden)

    Lenore Fahrig

    2009-12-01

    Full Text Available A key goal in road ecology is to determine which species are most vulnerable to the negative effects of roads on population persistence. Theory suggests that species that avoid roads are less likely to be negatively affected by roads than those that do not avoid roads. The goal of this study was to take a step toward testing this prediction by evaluating the behavioral response to roads and traffic of a species whose populations are known to be negatively affected by roads and traffic, the northern leopard frog (Rana pipiens. We studied the movement patterns of northern leopard frogs during their spring migration from overwintering sites in a river to various breeding ponds that were disconnected from the river by roads. We performed short-distance translocations of migrating frogs, followed them visually, and documented their movement coordinates following each hop, both near the roads and in non-roaded areas. We found that frogs took longer to move near roads with more traffic and that their movement was quickest in areas without roads nearby. Frogs tended to deviate more from a straight-line course when they were released near roads than compared with control areas, but this response was independent of traffic volume. All frogs released near roads attempted to cross the road. On very low traffic roads (10.86 mean vehicles per hour, 94% of frogs crossed the road successfully, whereas at higher traffic roads (58.29 mean vehicles per hour 72% were successful. Our results suggest that frog's inability to avoid going onto roads and their slow movement combine to make them particularly vulnerable to road mortality, which likely explains the strong negative effects of roads on frog population abundance. Conservation efforts should focus on preventing frogs from accessing the road surface through the use of drift fencing and culverts.

  2. Conditions controlling the onset of breeding migration of the Japanese mountain stream frog, Rana sakuraii

    Science.gov (United States)

    Miwa, Tokio

    2007-07-01

    I studied the conditions controlling the timing of breeding migration of the Japanese mountain stream frog Rana sakuraii, an explosive breeder, over 9 years (1992, 1993 and 1999-2005). I analysed two factors: the daily cumulative temperature (DCT) during hibernation and the triggering temperature on the day of migration onset. Frogs hibernated in shallow running water in streams in December. A total of 53,155 breeding migrating adults were captured by traps. Every year, breeding migration was induced by a rise in daily maximum water temperature to about 5°C. However, its date was limited to 1 February at the earliest, and the onset needed a DCT (from 20 January, using 3°C as the threshold for daily effective temperature) of at least about 15°C. Earlier (e.g. in mid- or late January), even if the maximum temperature rose to 5-8°C, migration did not begin. Moreover, even in early February, if the maximum temperature rose to 5°C, if it had been too cold in January and the DCT was low, migration would not begin until mid- or late February. Thus, the earliest date of readiness for migration varied from 1 February to mid-February, depending on the winter DCT. Logistic regression analyses showed that both factors, the DCT and the daily temperature, were significant. I propose that in temperate-zone amphibian explosive breeders, both the passing of an essential number of days and an essential DCT during hibernation are prerequisites for the onset of breeding migration before the daily temperature rises to the threshold.

  3. Trait performance correlations across life stages under environmental stress conditions in the common frog, Rana temporaria.

    Directory of Open Access Journals (Sweden)

    Frank Johansson

    Full Text Available If an organism's juvenile and adult life stages inhabit different environments, certain traits may need to be independently adapted to each environment. In many organisms, a move to a different environment during ontogeny is accompanied by metamorphosis. In such organisms phenotypic induction early in ontogeny can affect later phenotypes. In laboratory experiments we first investigated correlations between body morphology and the locomotor performance traits expressed in different life stages of the common frog, Rana temporaria: swimming speed and acceleration in tadpoles; and jump-distance in froglets. We then tested for correlations between these performances across life stages. We also subjected tadpoles to unchanging or decreasing water levels to explore whether decreasing water levels might induce any carry-over effects. Body morphology and performance were correlated in tadpoles; morphology and performance were correlated in froglets: hence body shape and morphology affect performance within each life stage. However, performance was decoupled across life stages, as there was no correlation between performance in tadpoles and performance in froglets. While size did not influence tadpole performance, it was correlated with performance of the metamorphosed froglets. Experiencing decreasing water levels accelerated development time, which resulted in smaller tadpoles and froglets, i.e., a carry-over effect. Interestingly, decreasing water levels positively affected the performance of tadpoles, but negatively affected froglet performance. Our results suggest that performance does not necessarily have to be correlated between life stages. However, froglet performance is size dependent and carried over from the tadpole stage, suggesting that some important size-dependent characters cannot be decoupled via metamorphosis.

  4. Cadmium-induced oxidative stress and apoptosis in the testes of frog Rana limnocharis

    International Nuclear Information System (INIS)

    Highlights: ► Cd can cause vacuoles and deformity of the spermatogenic cells in the frog testes. ► Cd can result in oxidative stress in the frog testes. ► Cd can induce significantly increase of ROS contents triggered DNA damages in the frog testes. ► Cd can cause apoptosis in the testes of male R. limnocharis. ► Apoptosis by Cd in the frog testes is related to Caspase-3, Bax and Bcl-2 genes. - Abstract: This study explored the genetic damage induced by cadmium exposure in the testes of Rana limnocharis. Healthy adult frogs were exposed to 2.5, 5, 7.5, or 10 mg/L of cadmium solution for 14 days. The results showed that exposure to these concentrations increased the levels of reactive oxygen species and malondialdehyde content in the testes, clearly indicating a dose–effect relationship. Moreover, the same dosages of Cd2+ solution increased glutathione (reduced) content, with the values being significantly different from those observed in the control group (P < 0.01). The comet assay results demonstrated that the DNA damage rate, tail length, and tail moment of samples obtained from frogs exposed to 2.5–7.5 mg/L of cadmium solution significantly increased compared with those of samples obtained from the control group (P < 0.01). These findings suggest that cadmium can induce free radical generation, followed by lipid peroxidation and DNA damage. Ultrastructural observation revealed vacuoles in the spermatogenic cells, cell dispersion, incomplete cell structures, and deformed nucleoli. Moreover, cadmium exposure induced significant down-regulation of Bcl-2 expression and up-regulation of Bax and caspase-3 expressions. Taken together, these data indicate that cadmium can induce testicular cell apoptosis in R. limnocharis. Exploring the effects of cadmium on the mechanism of reproductive toxicity in amphibians will help provide a scientific basis accounting for the global population decline in amphibian species.

  5. Gonadal differentiation in frogs, Rana japonica and R. brevipoda, raised from UV irradiated eggs

    International Nuclear Information System (INIS)

    The gonadal differentiation of anurans, Rana japonica and R. brevipoda, was examined in animals raised from eggs which had been irradiated at the vegetal hemisphere with UV (9300 erg/mm2) at the 2-cell stage. In R. japonica about 70% of the larvae at stage I from the pressed and UV-irradiated eggs were germ cell free, but at a stage immediately after metamorphosis all animals had at least some germ cells, although their gonads often were extremely small and poorly differentiated. When male animals matured sexually, many of them had abnormal gonads. However, all of them were shown by artificial means to be capable of fertilization. In the nonpressed and irradiated group, no larvae were germ cell free and the animals immediately after metamorphosis showed nearly normal gonadal differentiation except for the presence of a few degenerate oocytes in the ovaries. The results in R. brevipoda were basically similar to those in R. japonica. In both species, sex ratios were determined at two stages, the first immediately after metamorphosis and the other when the animals matured, as based on gonad morphology and histology and on external sexually dimorphic characters as well. Sex ratios at these two stages in frogs from the pressed and irradiated eggs differed markedly in R. brevipoda. The ratio was normal at metamorphosis but high M/F ratios occurred when animals became mature. That sex reversal took place in this species as well as in R. japonica (in which sex-ratio deviation was not statistically significant) was supported by the sex ratios of the progenies of these supernumerary males

  6. Effects of wetland vs. landscape variables on parasite communities of Rana pipiens: links to anthropogenic factors

    Science.gov (United States)

    Schotthoefer, Anna M.; Rohr, Jason R.; Cole, Rebecca A.; Koehler, Anson V.; Johnson, Catherine M.; Johnson, Lucinda B.; Beasley, Val R.

    2011-01-01

    The emergence of several diseases affecting amphibian populations worldwide has prompted investigations into determinants of the occurrence and abundance of parasites in frogs. To understand the spatial scales and identify specific environmental factors that determine risks of parasitism in frogs, helminth communities in metamorphic frogs of the northern leopard frog (Rana pipiens) were examined in relation to wetland and landscape factors at local (1 km) and regional (10 km) spatial extents in an agricultural region of Minnesota (USA) using regression analyses, ordination, and variance partitioning techniques. Greater amounts of forested and woody wetland habitats, shorter distances between woody wetlands, and smaller-sized open water patches in surrounding landscapes were the most consistently positive correlates with the abundances, richness, and diversity of helminths found in the frogs. Wetland and local landscape variables were suggested as most important for larval trematode abundances, whereas local and regional landscape variables appeared most important for adult helminths. As previously reported, the sum concentration of atrazine and its metabolite desethylatrazine, was the strongest predictor of larval trematode communities. In this report, we highlight the additional influences of landscape factors. In particular, our data suggest that anthropogenic activities that have resulted in the loss of the availability and connectivity of suitable habitats in the surrounding landscapes of wetlands are associated with declines in helminth richness and abundance, but that alteration of wetland water quality through eutrophication or pesticide contamination may facilitate the transmission of certain parasite taxa when they are present at wetlands. Although additional research is needed to quantify the negative effects of parasitism on frog populations, efforts to reduce inputs of agrochemicals into wetlands to limit larval trematode infections may be warranted

  7. Toxic Effects of Three Heavy Metallic Ions on Rana zhenhaiensis Tadpoles

    Institute of Scientific and Technical Information of China (English)

    Li WEI; Guohua DING; Sainan GUO; Meiling TONG; Wenjun CHEN; Jon FLANDERS; Weiwei SHAO; Zhihua LIN

    2015-01-01

    Heavy metal pollution is widespread in some areas of China and results in contamination of land, water, and air with which all living organisms interact. In this study, we used three heavy metallic ions (Cu2+, Pb2+ and Zn2+) to assess their toxicity effects on mortality, blood biomarker and growth traits (body length and body mass) of Rana zhenhaiensis tadpoles. The results showed that the toxicity levels of the three metallic ions were different when conducted with different experiment designs. For acute toxicity tests, Cu2+ was the most toxic with the highest tadpole mortality. The mortalities of tadpoles showed significant differences among the treatments at the same exposure time endpoints (24, 48, 72 and 96h). Results from repeated measures ANOVA indicated that metallic ion concentration, exposure time and their interactions significantly affected the mortalities of R. zhenhaiensis tadpoles. Also, the toxicity effects of all binary combinations of the three metallic ion treatments showed synergism. The half lethal concentrations (LC50) decreased with increasing exposure time during the experimental period, and the safe concentration (SC)values of Cu2+, Pb2+ and Zn2+ were different from each other. Combined and compared LC50 values with previous data reported, it is suggestes that the toxicity levels of metal pollution to anuran tadpoles should be species-and age-related. For blood biomarker tests, Zn2+ was the most toxic with the highest total frequencies of abnormal erythrocytic nucleus. All three metallic ions caused higher abnormal erythrocytic nucleus compared with control groups. In a chronic toxicity test, Pb2+ was the most toxic with lowest growth traits. Survival rate (except for 18 days), total body length and body mass showed significant differences among the treatments. These findings indicated that tadpoles of R. zhenhaiensis should be as a bioindicator of heavy metals pollution.

  8. A new gorgoderid species of the urinary bladder of Rana zweifeli from Michoacán, Mexico Una nueva especie de gorgodérido de la vejiga urinaria de Rana zweifeli de Michoacán, México

    Directory of Open Access Journals (Sweden)

    Rosario Mata-López

    2006-12-01

    Full Text Available Gorgoderina tarascae n. sp. is described from the urinary bladder of Rana zweifeli, from Cutzaróndiro, Michoacán, Mexico. Gorgoderina tarascae differs from the other species of the genus by possessing the following combination of characters: follicular vitelline glands, arranged in two clusters of 4-7 follicles dorsal to the ovary, compact and smooth reproductive organs situated far from each other and from the acetabulum, suckers close to each other, and a slender, spindle shaped body with a flexed position due to the situation of the acetabulum.Gorgoderina tarascae n. sp. se describe como parásita de la vejiga urinaria de Rana zweifeli de Cutzaróndiro, Michoacán, México. Gorgoderina tarascae difiere del resto de las especies del género por la siguiente combinación de características: posee glándulas vitelógenas arregladas en dos racimos de 4-7 folículos situados dorsalmente al ovario, órganos reproductivos compactos y de bordes lisos, muy separados entre si y con respecto del acetábulo, ventosas cercanas una de la otra y cuerpo delgado, en forma de huso y flexionado debido a la posición del acetábulo.

  9. Effects of glyphosate and the glyphosate based herbicides Roundup Original(®) and Roundup Transorb(®) on respiratory morphophysiology of bullfrog tadpoles.

    Science.gov (United States)

    Rissoli, Rafael Zanelli; Abdalla, Fabio Camargo; Costa, Monica Jones; Rantin, Francisco Tadeu; McKenzie, David John; Kalinin, Ana Lucia

    2016-08-01

    Glyphosate-based herbicides are widely used in agriculture and are commonly found in water bodies. Roundup Original(®) (RO) contains an isopropylamine glyphosate (GLY) salt containing the surfactant POEA, while Roundup Transorb R(®) (RTR) contains a potassium salt of GLY with unknown surfactants. Both contain different compositions of so-called "inert" ingredients, more toxic than glyphosate. Amphibian tadpoles often experience variations in O2 availability in their aquatic habitats; an ability to tolerate hypoxia can condition their survival and fitness. We evaluated the impacts of sublethal concentrations of GLY (1 mg L(-1)), RO (1 mg L(-1) GLY a.e) and RTR (1 mg L(-1) GLY a.e) on metabolic rate (V·O2 - mLO2 Kg1 h(-1)) of bullfrog tadpoles during normoxia and graded hypoxia, and related this to morphology of their skin, their major site of gas exchange. In control (CT) V·O2 remained unaltered from normoxia until 40 mmHg, indicating a critical O2 tension between 40 and 20 mmHg. GLY significantly reduced V·O2, possibly due to epidermal hypertrophy, which increased O2 diffusion distance to O2 uptake. In contrast, RTR increased V·O2 during hypoxia, indicating an influence of "inert" compounds and surfactants. V·O2 of RO did not differ from CT, suggesting that any increase in V·O2 caused by exposure was antagonized by epidermal hypertrophy. Indeed, all herbicides caused marked alterations in skin morphology, with cell and epithelium wall presenting hyperplasia or hypertrophy and chromatid rupture. In summary, GLY, RO and RTR exert different effects in bullfrog tadpoles, in particular the surfactants and inert compounds appear to influence oxygen uptake. PMID:27160633

  10. Multiple saxitoxin-binding sites in bullfrog muscle: tetrodotoxin-sensitive sodium channels and tetrodotoxin-insensitive sites of unknown function

    International Nuclear Information System (INIS)

    The possible presence of multiple sodium channel subtypes in bullfrog skeletal muscle was investigated in binding experiments with [3H]saxitoxin and in single-channel studies using planar lipid bilayers. Two classes of [3H]saxitoxin-binding sites were identified in membrane preparations. One class displayed a toxin specificity characteristic of voltage-dependent sodium channels: high affinity for saxitoxin (KD approximately equal to 0.5 nM), neosaxitoxin (KD approximately equal to 0.1 nM), and tetrodotoxin (KD approximately equal to 1.3 nM). A second class of membrane-associated binding sites exhibited high affinity for saxitoxin (KD approximately equal to 0.1 nM), lower affinity for neosaxitoxin (KD approximately equal to 25 nM), and complete insensitivity to tetrodotoxin at concentrations up to 32 microM. The first class corresponded to functional tetrodotoxin-sensitive sodium channels that could be incorporated and observed in planar bilayers in the presence of batrachotoxin. The unusual, tetrodotoxin-insensitive binding activity for [3H]saxitoxin was also found at nM levels in the high speed supernatant of homogenized skeletal muscle without the addition of detergents. This soluble class of sites exhibited low affinity for neosaxitoxin (KD approximately equal to 60 nM) and a very slow dissociation rate of [3H]saxitoxin (t0.5 approximately equal to 90 min), properties nearly identical to those of the tetrodotoxin-insensitive sites in membranes. The soluble saxitoxin-binding activity is also characterized by a more basic pH dependence and a complete lack of binding competition between saxitoxin and alkali cations. Bullfrog muscle appears to be a good tissue source for the purification of this soluble saxitoxin-binding protein

  11. Expression of P450arom and Estrogen Receptor Alpha in the Oviduct of Chinese Brown Frog (Rana dybowskii during Prehibernation

    Directory of Open Access Journals (Sweden)

    Ji Weng

    2015-01-01

    Full Text Available One specific physiological phenomenon of Chinese brown frog (Rana dybowskii is that its oviduct expands prior to hibernation instead of expanding during the breeding period. In this study, we investigated the expression of P450arom and estrogen receptors α and β (ERα and ERβ in the oviduct of Rana dybowskii during the breeding period and prehibernation. The results of the present study showed that there were significant differences in both oviductal weight and size with values markedly higher in prehibernation than in the breeding period. P450arom was observed in stromal tissue in both the breeding period and prehibernation. ERα was expressed in stromal tissue and epithelial cells in both periods, whereas ERβ could not be detected. The mean protein and mRNA levels of P450arom and ERα were significantly higher in prehibernation as compared to the breeding period. Besides, oviductal content of 17β-estradiol was also higher in prehibernation than in the breeding period. These results suggested that estrogen may play autocrine/paracrine roles mediated by ERα in regulating the oviductal hypertrophy during prehibernation.

  12. Characterization of Portuguese geomaterials, the clay component of ranas, as potential liners for low and intermediate radioactive disposal sites

    International Nuclear Information System (INIS)

    Safety assessment of low and intermediate level waste (LILW) repositories requires the understanding of radionuclides sorption-desorption mechanisms, mainly the degree of interaction between radionuclides and mineral surfaces. Among the different radionuclides that are part of the Portuguese radwastes' inventory 137Cs is one of the most important from the radiological point of view due to its high radiotoxicity. The clay component of natural geomaterials termed ranas, originated from an area located in the NE Mainland of Portugal, was studied for their potential as effective barriers. These geomaterials (grains-size fractions <63 μm, <36 μm) were characterized in terms of cationic exchange capacity (CEC), frayed edge sites (FES) and radiocaesium interception potential (RIP). Organic matter content and pH were also determined. The fractions were mineralogically analyzed by X-ray diffraction and by instrumental neutron activation analysis (INAA) for chemical elemental composition. Smectite (montmorillonite), illite, kaolinite were identified. The capacity of FES is related to the samples granulometry as opposed to what was observed for CEC and RIP. The behavior of ranas was not similar for all samples which may be related to differences in mineralogy. Future studies with regard to the behaviour of radiocaesium are expected to clarify the possible application of these geomaterials as liner/backfill/buffer for a LILW repository. (author)

  13. Extra-intestinal localization of Goussia sp (Apicomplexa) oocysts in Rana dalmatina (Anura: Ranidae), and the fate of infection after metamorphosis

    Czech Academy of Sciences Publication Activity Database

    Jirků, M.; Modrý, David

    2006-01-01

    Roč. 70, č. 3 (2006), s. 237-241. ISSN 0177-5103 R&D Projects: GA ČR GA206/03/1544; GA ČR GD524/03/H133 Institutional research plan: CEZ:AV0Z60220518 Keywords : Goussia * Rana * Coccidia Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.509, year: 2006

  14. Directionality of auditory nerve fiber responses to pure tone stimuli in the grassfrog, Rana temporaria. I. Spike rate responses

    DEFF Research Database (Denmark)

    Jørgensen, M B; Christensen-Dalsgaard, J

    1997-01-01

    We studied the directionality of spike rate responses of auditory nerve fibers of the grassfrog, Rana temporaria, to pure tone stimuli. All auditory fibers showed spike rate directionality. The strongest directionality was seen at low frequencies (200-400 Hz), where the spike rate could change by...

  15. cytogenetic effects in populations of amphibians Rana arvalis living on the radio-contaminated area

    Energy Technology Data Exchange (ETDEWEB)

    Yushkova, E.; Bodnar, I.; Zainullin, V. [Institute of Biology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences (Russian Federation)

    2014-07-01

    The study of the features reactions of the animals a differing complicated individual development (metamorphosis) and living in conditions of radioactive contamination is an important trend in the modern radio-ecology. This information is of interest not only from the point of view of detection the mechanisms of radiobiological effects (hyper-radiosensitivity, hormesis, radio-adaptation, etc.) but also viewpoint of predicting delayed radiation effects that is necessary at account the normalization of technogeneous loading on natural ecosystems. An assessment of the level of cytogenetic damages (single-strand and double-strand DNA breaks) in the blood cells of tadpoles of Rana arvalis living in areas contaminated of wastes radium production (Russia, Komi Republic, Ukhta district) was conducted. Using this biological matter as a bioindicator due to the fact that development amphibian is carried out by metamorphosis and includes larval stage. At this stage post-embryonic development of an individual are the most sensitive to anthropogenic impact. To exclude the effects of other factors (temperature, age-specific peculiarities, overpopulation, etc.) on the formation of DNA damages from the studied reservoirs were taken laying eggs of amphibians (12-15 egg laying from the area) which afterwards are contain in strictly controlled laboratory conditions using water, belt silt, plants of native pond. The reaction of amphibians on the contamination was assessed by the level of DNA damage by method Comet assay was determined. With each egg laying were selected for 7 even-aged individuals. Total for cytogenetic analysis was used 189 individuals. It is shown that in animals that develop on the radio-contaminated area the level of single-strand DNA (alkaline pH version of the Comet assay) was higher than in the control area. According an estimate to the level of double-strand DNA (neutral pH version of the Comet assay) significant differences not was found. The high variability

  16. Cadmium-induced oxidative stress and apoptosis in the testes of frog Rana limnocharis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Hangjun; Cai Chenchen; Shi Cailei; Cao Hui; Han Ziliu [Department of Environmental Sciences, Hangzhou Normal University, Xuelin Road 16, Xiasha Gaojiao Dongqu, Hangzhou, Zhejiang Province, 310036 (China); Jia Xiuying, E-mail: hznujiaxiuying@126.com [Department of Environmental Sciences, Hangzhou Normal University, Xuelin Road 16, Xiasha Gaojiao Dongqu, Hangzhou, Zhejiang Province, 310036 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Cd can cause vacuoles and deformity of the spermatogenic cells in the frog testes. Black-Right-Pointing-Pointer Cd can result in oxidative stress in the frog testes. Black-Right-Pointing-Pointer Cd can induce significantly increase of ROS contents triggered DNA damages in the frog testes. Black-Right-Pointing-Pointer Cd can cause apoptosis in the testes of male R. limnocharis. Black-Right-Pointing-Pointer Apoptosis by Cd in the frog testes is related to Caspase-3, Bax and Bcl-2 genes. - Abstract: This study explored the genetic damage induced by cadmium exposure in the testes of Rana limnocharis. Healthy adult frogs were exposed to 2.5, 5, 7.5, or 10 mg/L of cadmium solution for 14 days. The results showed that exposure to these concentrations increased the levels of reactive oxygen species and malondialdehyde content in the testes, clearly indicating a dose-effect relationship. Moreover, the same dosages of Cd{sup 2+} solution increased glutathione (reduced) content, with the values being significantly different from those observed in the control group (P < 0.01). The comet assay results demonstrated that the DNA damage rate, tail length, and tail moment of samples obtained from frogs exposed to 2.5-7.5 mg/L of cadmium solution significantly increased compared with those of samples obtained from the control group (P < 0.01). These findings suggest that cadmium can induce free radical generation, followed by lipid peroxidation and DNA damage. Ultrastructural observation revealed vacuoles in the spermatogenic cells, cell dispersion, incomplete cell structures, and deformed nucleoli. Moreover, cadmium exposure induced significant down-regulation of Bcl-2 expression and up-regulation of Bax and caspase-3 expressions. Taken together, these data indicate that cadmium can induce testicular cell apoptosis in R. limnocharis. Exploring the effects of cadmium on the mechanism of reproductive toxicity in amphibians will help provide a

  17. Regulation of 5'-adenosine monophosphate deaminase in the freeze tolerant wood frog, Rana sylvatica

    Directory of Open Access Journals (Sweden)

    Storey Kenneth B

    2008-04-01

    Full Text Available Abstract Background The wood frog, Rana sylvatica, is one of a few vertebrate species that have developed natural freeze tolerance, surviving days or weeks with 65–70% of its total body water frozen in extracellular ice masses. Frozen frogs exhibit no vital signs and their organs must endure multiple stresses, particularly long term anoxia and ischemia. Maintenance of cellular energy supply is critical to viability in the frozen state and in skeletal muscle, AMP deaminase (AMPD plays a key role in stabilizing cellular energetics. The present study investigated AMPD control in wood frog muscle. Results Wood frog AMPD was subject to multiple regulatory controls: binding to subcellular structures, protein phosphorylation, and effects of allosteric effectors, cryoprotectants and temperature. The percentage of bound AMPD activity increased from 20 to 35% with the transition to the frozen state. Bound AMPD showed altered kinetic parameters compared with the free enzyme (S0.5 AMP was reduced, Hill coefficient fell to ~1.0 and the transition to the frozen state led to a 3-fold increase in S0.5 AMP of the bound enzyme. AMPD was a target of protein phosphorylation. Bound AMPD from control frogs proved to be a low phosphate form with a low S0.5 AMP and was phosphorylated in incubations that stimulated PKA, PKC, CaMK, or AMPK. Bound AMPD from frozen frogs was a high phosphate form with a high S0.5 AMP that was reduced under incubation conditions that stimulated protein phosphatases. Frog muscle AMPD was activated by Mg·ATP and Mg·ADP and inhibited by Mg·GTP, KCl, NaCl and NH4Cl. The enzyme product, IMP, uniquely inhibited only the bound (phosphorylated enzyme from muscle of frozen frogs. Activators and inhibitors differentially affected the free versus bound enzyme. S0.5 AMP of bound AMPD was also differentially affected by high versus low assay temperature (25 vs 5°C and by the presence/absence of the natural cryoprotectant (250 mM glucose that

  18. cytogenetic effects in populations of amphibians Rana arvalis living on the radio-contaminated area

    International Nuclear Information System (INIS)

    The study of the features reactions of the animals a differing complicated individual development (metamorphosis) and living in conditions of radioactive contamination is an important trend in the modern radio-ecology. This information is of interest not only from the point of view of detection the mechanisms of radiobiological effects (hyper-radiosensitivity, hormesis, radio-adaptation, etc.) but also viewpoint of predicting delayed radiation effects that is necessary at account the normalization of technogeneous loading on natural ecosystems. An assessment of the level of cytogenetic damages (single-strand and double-strand DNA breaks) in the blood cells of tadpoles of Rana arvalis living in areas contaminated of wastes radium production (Russia, Komi Republic, Ukhta district) was conducted. Using this biological matter as a bioindicator due to the fact that development amphibian is carried out by metamorphosis and includes larval stage. At this stage post-embryonic development of an individual are the most sensitive to anthropogenic impact. To exclude the effects of other factors (temperature, age-specific peculiarities, overpopulation, etc.) on the formation of DNA damages from the studied reservoirs were taken laying eggs of amphibians (12-15 egg laying from the area) which afterwards are contain in strictly controlled laboratory conditions using water, belt silt, plants of native pond. The reaction of amphibians on the contamination was assessed by the level of DNA damage by method Comet assay was determined. With each egg laying were selected for 7 even-aged individuals. Total for cytogenetic analysis was used 189 individuals. It is shown that in animals that develop on the radio-contaminated area the level of single-strand DNA (alkaline pH version of the Comet assay) was higher than in the control area. According an estimate to the level of double-strand DNA (neutral pH version of the Comet assay) significant differences not was found. The high variability

  19. Study on Manual Ova Hatching of Rana chinensis%中国林蛙卵人工孵化试验

    Institute of Scientific and Technical Information of China (English)

    于立忠; 孔祥文; 周永斌; 殷有

    2001-01-01

    his paper deals with the manual ova hatching of Rana chinensis.It is eviden that there are three different periods in the ova eclosion. The first period is at 75~80℃of effective water cumulative temperature. The peak period is at 100~120℃. The end is at 120~140℃. The most suitabale temperature of ova eclosion is 11~13℃. In this case, the eclosion speed is 1.6~2.2, and incubation period is 9~12 days,with the rate of eclosion over 80%. Manual hatching can increase the eclosion speed of ova. It is 10%~60% higher than CK, and also 25%~100% higher than the outdoor.

  20. Size-sex variation in survival rates and abundance of pig frogs, Rana grylio, in northern Florida wetlands

    Science.gov (United States)

    Wood, K.V.; Nichols, J.D.; Percival, H.F.; Hines, J.E.

    1998-01-01

    During 1991-1993, we conducted capture-recapture studies on pig frogs, Rana grylio, in seven study locations in northcentral Florida. Resulting data were used to test hypotheses about variation in survival probability over different size-sex classes of pig frogs. We developed multistate capture-recapture models for the resulting data and used them to estimate survival rates and frog abundance. Tests provided strong evidence of survival differences among size-sex classes, with adult females showing the highest survival probabilities. Adult males and juvenile frogs had lower survival rates that were similar to each other. Adult females were more abundant than adult males in most locations at most sampling occasions. We recommended probabilistic capture-recapture models in general, and multistate models in particular, for robust estimation of demographic parameters in amphibian populations.

  1. Development of antimicrobial peptide defenses of southern leopard frogs, Rana sphenocephala, against the pathogenic chytrid fungus, Batrachochytrium dendrobatidis.

    Science.gov (United States)

    Holden, Whitney M; Reinert, Laura K; Hanlon, Shane M; Parris, Matthew J; Rollins-Smith, Louise A

    2015-01-01

    Amphibian species face the growing threat of extinction due to the emerging fungal pathogen Batrachochytrium dendrobatidis, which causes the disease chytridiomycosis. Antimicrobial peptides (AMPs) produced in granular glands of the skin are an important defense against this pathogen. Little is known about the ontogeny of AMP production or the impact of AMPs on potentially beneficial symbiotic skin bacteria. We show here that Rana (Lithobates) sphenocephala produces a mixture of four AMPs with activity against B. dendrobatidis, and we report the minimum inhibitory concentration (MIC) of synthesized replicates of these four AMPs tested against B. dendrobatidis. Using mass spectrometry and protein quantification assays, we observed that R. sphenocephala does not secrete a mature suite of AMPs until approximately 12 weeks post-metamorphosis, and geographically disparate populations produce a different suite of peptides. Use of norepinephrine to induce maximal secretion significantly reduced levels of culturable skin bacteria. PMID:25218643

  2. Effects of two endocrine disruptors Prochloraz and Ethinylestradiol on development of Rana Temporaria

    DEFF Research Database (Denmark)

    Brande-Lavridsen, Nanna; Christensen-Dalsgaard, Jakob; Korsgaard, Bodil

    2009-01-01

    effect of endocrine disruptors on the sexsteroid axis and reproductive function. However, another hormone system, the thyroid hormone axis may equally well be affected by xenobiotics. Thyroid hormones are essential in stimulating all aspects of amphibian metamorphosis and thyroid hormone disruptors may...... therefore severely affect this most critical process in amphibian life history. We found that exposure of tadpole Rana temporaria to the synthetic estrogen ethinylestradiol and the fungicide prochloraz caused delay of metamorphosis accompanied by changes in thyroid gland morphology....... phenotypic males. Moreover, ethinylestradiol caused estrogen-dependent induction of the egg yolk precursor protein vitellogenin. These results show that gonadal development and vitellogenin induction may be used as biomarkers for detection of endocrine disrupting chemicals. Most studies have focused on the...

  3. Prevalence of the pathogenic chytrid fungus, Batrachochytrium dendrobatidis, in an endangered population of northern leopard frogs, Rana pipiens

    Directory of Open Access Journals (Sweden)

    Govindarajulu Purnima

    2010-03-01

    Full Text Available Abstract Background Emerging infectious diseases threaten naïve host populations with extinction. Chytridiomycosis, an emerging infectious disease of amphibians, is caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd and has been linked to global declines in amphibians. Results We monitored the prevalence of Bd for four years in the Northern leopard frog, Rana pipiens, which is critically imperiled in British Columbia (BC, Canada. The prevalence of Bd initially increased and then remained constant over the last three years of the study. Young of the year emerging from breeding ponds in summer were rarely infected with Bd. Some individuals cleared their Bd infections and the return rate between infected and uninfected individuals was not significantly different. Conclusions The BC population of R. pipiens appears to have evolved a level of resistance that allows it to co-exist with Bd. However, this small population of R. pipiens remains vulnerable to extinction.

  4. Relation between equatorial x-ray intensities and isometric twitch forces in frog skeletal muscle

    International Nuclear Information System (INIS)

    The sartorius muscle of bullfrog (Rana catesbeiana) was mounted vertically in an experimental chamber. The nuscle was continuously perfused with Ringer solution, and stimulated with single 2 msec supramaximal current pulses. The equatorial X-ray diffraction pattern (specimen to detector distance, 40 cm) during isometric twitches was recorded with a linear position-sensitive proportional counter, and the data were registered in a computer memory system. With an increase of temperature from 5 to 220C, the magnitude of peak twitch force was reduced by about 50% with a marked decrease in the duration of mechanical response, while the minimum value of Isub(1.0)/Isub(1.1) attained during a twitch increased by more than twofold. On the other hand, the equatorial reflection from resting and fully tetanized muscles showed no appreciable dependence on temperature, though the steady tetanic force P0 increased by about 10% with an increase in temperature from 5 to 250C. The intensity ratio is not a linear function of isometric force developed. (Namekawa, k.)

  5. Time-resolved x-ray diffraction from frog skeletal muscle during shortening against an inertial load and a quick release

    International Nuclear Information System (INIS)

    A group of Japanese researchers conducted, for the first time in this field, experiments on time-resolved x-ray diffraction of frog (bullfrog, Rana catesbeiana) skeletal muscle in conditions where both the force and the muscle length change with time. During an isotonic twitch under a load of about 0.3 P0, the intensity ratio started falling on stimulation and reached a minimum value of 0.5 - 0.6 at the early shortening phase, which was maintained until the beginning of relaxation. Except that the minimum value was not retained until the start of relaxation, the same was observed during a twitch against an inertial load whereby the peak force exerted by the muscle was about 0.4 P0. The results may be taken to indicate that the change in the intensity ratio reflects not the time course of shortening but that of force generation. When a quick release (3 - 4% of muscle length) was applied during the rising phase of an isometric twitch, the intensity ratio showed no distinct change. Judging from tentative calculation results, however, the foregoing result is subject to further experiments with a much improved time resolution of the measurements. (Kitajima, A.)

  6. Post-evaluation of the neurophaties treatment post-trauma with therapeutic laser. Model in sciatic nerve of frog

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the compound nerve action potential amplitude and latency measured to determine the degree of myelination and the number of fibers stimulated in a model of stimulated frog sciatic nerve laser at 810 nm as perioperative treatment after injury. It used 30 bullfrogs (Rana catesbeiana) to obtain 60 sciatic nerves forming four groups, groups 1 and 2 worked with nerves in vitro, were dissected in humid chambers for placing isolated organ, was recorded on compound nerve action potential, the second group laser was applied at 24, 48, 72, 96 and 120 hours and at the same time were placed in 10% formalin. Groups 3 and 4 are worked in vivo localizing the nerve and causing damage through compression, occurred over the compound nerve action potential to assess the degree of myelination and the number of fibers stimulated, the group 4 was applied to 810 nm laser (500 Hz, 10 J, 200 mW) after injury, after 48 hours, three frogs were sacrificed by introducing the nerves in 10% formalin. The latency recorded by stimulating the sciatic nerve of frog to 0.5 mA and 100 ms in groups 1 and 2 show significant differences (p000), as to the extent, if any statistically significant difference. (p<0.001 and p<0.000). The laser produces a favorable response in the treatment of paresthesia (post-traumatic neuropathy).

  7. Low detection of ranavirus DNA in wild postmetamorphic green frogs, Rana (Lithobates) clamitans, despite previous or concurrent tadpole mortality.

    Science.gov (United States)

    Forzán, María J; Wood, John

    2013-10-01

    Ranavirus (Iridoviridae) infection is a significant cause of mortality in amphibians. Detection of infected individuals, particularly carriers, is necessary to prevent and control outbreaks. Recently, the use of toe clips to detect ranavirus infection through PCR was proposed as an alternative to the more frequently used lethal liver sampling in green frogs (Rana [Lithobates] clamitans). We attempted reevaluate the use of toe clips, evaluate the potential use of blood onto filter paper and hepatic fine needle aspirates (FNAs) as further alternatives, and explore the adequacy of using green frogs as a target-sampling species when searching for ranavirus infection in the wild. Samples were obtained from 190 postmetamorphic (≥1-yr-old) green frogs from five ponds on Prince Edward Island (PEI), Canada. Three of the ponds had contemporary or recent tadpole mortalities due to Frog Virus 3 (FV3) ranavirus. PCR testing for ranavirus DNA was performed on 190 toe clips, 188 blood samples, 72 hepatic FNAs, and 72 liver tissue samples. Only two frogs were ranavirus-positive: liver and toe clip were positive in one, liver only was positive in the other; all blood and FNAs, including those from the two positive frogs, were negative. Results did not yield a definitive answer on the efficacy of testing each type of sample, but resemble what is found in salamanders infected with Ambystoma tigrinum (rana)virus. Findings indicate a low prevalence of FV3 in postmetamorphic green frogs on PEI (≤2.78%) and suggest that green frogs are poor reservoirs (carriers) for the virus. PMID:24502715

  8. New species of Haematoloechus (Digenea: Plagiorchidae in the lung of the foothill yellow-legged frog Rana boylii (Anura, from Humboldt County, California, USA Especie nueva de Haematoloechus (Digenea: Plagiorchidae del pulmón de la rana de patas amarillas Rana boylii (Anura, de Humboldt County, California, Estados Unidos de América

    Directory of Open Access Journals (Sweden)

    David Zamparo

    2011-06-01

    Full Text Available A new species of Haematoloechus is described from the lungs of Rana boylii from Humboldt County, California. The new species is similar to Haematoloechus buttensis, Haematoloechus kernensis, and Haematoloechus complexus in general course of the uterus and gonad shape. It is similar to H. buttensis by having a cirrus sac terminating midway between the posterior margin of the pharynx and the anterior margin of the ovary, and having a smaller oral/ventral sucker ratio; to H. complexus by having the genital pore ventral to the pharynx, and it is similar to H. kernensis by having a larger oral sucker to pharynx width ratio. The new species is unique by lacking an extra-cecal longitudinal uterine loop from the hind-body. Molecularly, the new species differs 1.04-1.15% in partial 28S sequence with respect to H. complexus, and a monophyletic grouping of these specimens in a phylogenetic analysis of all available sequence data consistent with the species-specific status proposed herein. Evidence is also presented to suggest that specimens identified as H. buttensis in Rana pretiosa from British Columbia, Canada represents a new, but still undescribed species. The importance of conducting biological inventories of helminths, along with continued monitoring of populations, and collections based taxonomy are related.Una especie nueva de Haematoloechus es descrita de los pulmones de Rana boylii de Humboldt County, California. La especie nueva guarda semejanza con Haematoloechus buttensis, Haematoloechus kernensis, y Haematoloechus complexus en la disposición general del útero y en la forma de las gónadas. Es similar a H. buttensis en que la bolsa del cirro finaliza entre el margen posterior de la faringe y el margen anterior del ovario, y en presentar una relación menor entre la ventosa oral y el acetábulo; a H. complexus por tener el poro genital ventral a la faringe, y a H. kernensis por tener una relación mayor del ancho de la ventosa oral contra la

  9. Research on suppression function of compound prescription powder made from rana japonica oil on hydroxy free radical in serum of big mice exposed to X ray

    International Nuclear Information System (INIS)

    The models of Wistar big mice under X ray irradiation were copied and intervened by the compound prescription powder made from rana japonica oil, for the purpose to examines the ability of suppression on the hydroxy free radicals in the serum taken from each group of big mice which was being examined. Results show that the ability of prevention group of suppression hydroxy free radical is obviously higher than blank control group and tailored radiation group (p<0.05). Ability of treatment group suppress hydroxy free radically is obviously higher than tailored radiation group (p<0.05). There is not the remarkable difference between blank control group and tailored radiation group. The above results demonstrates that compound prescription powder mainly made from the rana japonica oil might assist to strengthen the suppression of serum taken from the big mice under X ray irradiation on the hydroxy free radical. (authors)

  10. A de novo Assembly of the Common Frog (Rana temporaria) Transcriptome and Comparison of Transcription Following Exposure to Ranavirus and Batrachochytrium dendrobatidis.

    OpenAIRE

    Price, S.J.; Garner, T. W.; Balloux, F.; Ruis, C.; Paszkiewicz, K. H.; Moore, K.; Griffiths, A. G.

    2015-01-01

    Amphibians are experiencing global declines and extinctions, with infectious diseases representing a major factor. In this study we examined the transcriptional response of metamorphic hosts (common frog, Rana temporaria) to the two most important amphibian pathogens: Batrachochytrium dendrobatidis (Bd) and Ranavirus. We found strong up-regulation of a gene involved in the adaptive immune response (AP4S1) at four days post-exposure to both pathogens. We detected a significant transcriptional ...

  11. Response of the Italian agile frog (Rana latastei) to a Ranavirus, frog virus 3: a model for viral emergence in naïve populations.

    OpenAIRE

    Pearman, P. B.; Garner, T. W. J.; Straub, M.; Greber, U F

    2004-01-01

    Ranavirus (family Iridoviridae) is a genus of pathogens of poikilotherms, and some ranaviruses may play a role in widespread mortality of amphibians. Ecology of viral transmission in amphibians is poorly known but can be addressed through experimentation in the laboratory. In this study, we use the Ranavirus frog virus 3 (FV3) as an experimental model for pathogen emergence in naive populations of tadpoles. We simulated emerging disease by exposing tadpoles of the Italian agile frog (Rana lat...

  12. Evidence of a progesterone receptor in the liver of the green frog Rana esculenta and its down-regulation by 17 beta estradiol and progesterone.

    Science.gov (United States)

    Paolucci, M; Guerriero, G; Ciarcia, G

    1999-12-01

    Progesterone is a versatile hormone showing an ample variety of effects. One of the numerous functions attributed to progesterone is the modulation of vitellogenesis in oviparous vertebrates. As a prerequisite for the possible involvement of progesterone in vitellogenesis modulation, we investigated the presence of a progesterone receptor (PR) in the liver of the female green frog Rana esculenta. 3H-Progesterone (3H-P) binding activity was found in both cytosol and nuclear extract of the liver of Rana esculenta. The progesterone-binding moiety showed the typical characteristics of a true receptor, such as high affinity, low capacity, and specificity for progesterone. It also bound to DNA-cellulose and was eluted with a linear salt gradient at a concentration of 0.05 M of NaCl. The progesterone-binding moiety was down regulated by steroid hormones, in that ovariectomy resulted in a significant increase, in both cytosol and nuclear extract, of 3H-P binding activity with respect to intact females. On the contrary, 3H-P binding activity was almost undetectable after estradiol and/or progesterone treatment. The progesterone binding moiety of Rana esculenta was analyzed by Western blotting with the aid of a monoclonal antibody raised against the subunits A and B of the chicken PR. An immunoreactive band of about 67 kDa was observed in the liver of both intact and treated females. The 67 kDa band showed an increased intensity in ovariectomized animals, while it was faint following treatment with estradiol and/or progesterone. This is the first report on the presence of a progesterone receptor (PR) in the liver of an amphibian. PR of Rana esculenta is down regulated by estradiol and/or progesterone and shows peculiar immunological and biochemical characteristics, which make it rather different from the PR of other vertebrates. PMID:10589507

  13. Element accumulation and levels of four biomarkers in common frog (Rana temporaria) tadpoles in two sedimentation ponds and a naturally occurring pond

    OpenAIRE

    Johansen, Susanne Lund

    2013-01-01

    During the last decades there has been an increasing awareness of pollution in tunnel wash water and highway runoff, and its ecotoxicological effects. The objectives of the present thesis were to investigate trace element accumulation and the levels of the biomarkers metallothionein (MT), 7-Ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST) and reduced glutathione (GSH) in common frog (Rana temporaria) embryos and tadpoles inhabiting Vassum and Skullerud sedimentation ponds ...

  14. Prevalence of the pathogenic chytrid fungus, Batrachochytrium dendrobatidis, in an endangered population of northern leopard frogs, Rana pipiens

    OpenAIRE

    Voordouw, Maarten J.; Adama, Doug; Houston, Barb; Govindarajulu, Purnima; Robinson, John

    2011-01-01

    Background Emerging infectious diseases threaten naïve host populations with extinction. Chytridiomycosis, an emerging infectious disease of amphibians, is caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd) and has been linked to global declines in amphibians. Results We monitored the prevalence of Bd for four years in the Northern leopard frog, Rana pipiens, which is critically imperiled in British Columbia (BC), Canada. The prevalence of Bd initially increased and then r...

  15. Reproduction of the exotic bullfrog Lithobates catesbeianus (Shaw, 1802 (Anura, Ranidae in creeks of the Atlantic Rainforest of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Lilian Gomes Afonso

    2010-09-01

    Full Text Available Reproduction of the exotic bullfrog Lithobates catesbeianus was studied every two months from January 2005 to December 2006, analyzing tadpoles, juveniles, and adult vocalizations at three creeks located in the largest Brazilian center of ornamental fish breeding. Absolute and relative tadpole frequencies were measured bimonthly in three development stages: G1 (no limbs, G2 (hind limbs present, G3 (fore and hind limbs and I (metamorphs. Results show that, during warmest months, a greater proportion of tadpoles in G1, G2, and G3 phases were found in Santo Antônio and Chato creeks, while G1, G3, and I phases were more common in Gavião creek. Tadpoles in G1 and G2 phases predominated in coldest months at all locations. Male calls and highest average water temperatures and rainfall were recorded at 3 streams during the hottest months. Management measures should be adopted, such as the extermination of larval and adult stages, and initiatives should be taken to prevent new re-introductions, such as: (1 installation of fences around tanks where adults are located, (2 placement of protective screens on the pipes that release waste water from tanks directly into streams, (3 capacity building and educational measures on the problems of biological invasions for staff working on ornamental fish farms.

  16. Concentration dependence of rapid axonal transport: a study of the transport kinetics of [35S]methionine-labeled protein in postganglionic sympathetic fibers of the bullfrog

    International Nuclear Information System (INIS)

    The kinetics of transport of radiolabeled proteins in sympathetic axons of the bullfrog sciatic nerve were examined after injection of [35S]methionine into the S9 sympathetic ganglion. Under resting conditions at 20 degrees C, the fastest moving material was carried distally at 5.7 +/- 0.3 mm/hr. Various manipulations of temperature in the proximal part of the nerve were used to alter the amount of protein transported into the distal region, which was always kept at 20 degrees C. The velocity in this test region was found to increase to over 9 mm/hr when material that had accumulated at a cold block for 4 hr was released by rewarming. This acceleration was transient, and base line velocity was regained after 2 hr. In order to increase the local concentration of transported protein by a second method, the proximal part of several nerves was warmed to 28 degrees C. Maximal transport velocity in the 20 degrees C test region rose to 6.2 +/- 0.12 mm/hr. To decrease the local concentration of transported protein, the proximal part of other nerves was cooled to 15 degrees C. Maximal transport velocity in the 20 degrees C test region fell to 4.7 +/- 0.7 mm/hr. We conclude that there is a small but real tendency for the velocity of rapid axonal transport in this neural system to be positively related to the availability of material suitable for transport

  17. The role of bicarbonate ions and of adenosine 3',5'-monophosphate (cAMP) in chloride transport by epithelial cells of bullfrog small intestine.

    Science.gov (United States)

    Armstrong, W M; Youmans, S J

    1980-01-01

    In an HCO3-free medium, isolated segments of bullfrog small intestine, stripped of their external muscle layers, displayed a small, serosal positive PD that did not, on the average, differ significantly from zero. Similarly, in this medium, the mean values of Isc and of net Na+ and Cl- absorption under short-circuit conditions did not differ significantly from zero. External HCO3- (25 mM) induced a highly significant serosal negative PD and Isc and a large net absorption of Cl-. Net Cl- absorption exceeded Isc, i.e., there was a significant net flux, JR, which was consistent with a net secretion of HCO3-. The ratio of the internal Cl-activity of the absorptive cells (alpha Cli) to its equilibrium value was larger in the presence than in the absence of HCO3-. In the presence of HCO3-, cAMP, added to the serosal medium, reversed the serosal negative PD and Isc, and inhibited, though it did not completely abolish, net Cl- absorption. JR was unchanged; tissue Cl- and alpha Cli were reduced, and tissue Na+ decreased and tissue K+ increased. When HCO3- and Cl- were removed from the bathing medium, the electrical response of the tissue to cAMP, though greatly attenuated, was not completely abolished. Under these conditions, cAMP induced a significant net Na+ absorption. A model for ion transport in the absorptive cells of the small intestine is proposed that is consistent with these findings. PMID:6249145

  18. Cliff swallows Petrochelidon pyrrhonota as bioindicators of environmental mercury, Cache Creek Watershed, California

    Science.gov (United States)

    Hothem, R.L.; Trejo, B.S.; Bauer, M.L.; Crayon, J.J.

    2008-01-01

    To evaluate mercury (Hg) and other element exposure in cliff swallows (Petrochelidon pyrrhonota), eggs were collected from 16 sites within the mining-impacted Cache Creek watershed, Colusa, Lake, and Yolo counties, California, USA, in 1997-1998. Nestlings were collected from seven sites in 1998. Geometric mean total Hg (THg) concentrations ranged from 0.013 to 0.208 ??g/g wet weight (ww) in cliff swallow eggs and from 0.047 to 0.347 ??g/g ww in nestlings. Mercury detected in eggs generally followed the spatial distribution of Hg in the watershed based on proximity to both anthropogenic and natural sources. Mean Hg concentrations in samples of eggs and nestlings collected from sites near Hg sources were up to five and seven times higher, respectively, than in samples from reference sites within the watershed. Concentrations of other detected elements, including aluminum, beryllium, boron, calcium, manganese, strontium, and vanadium, were more frequently elevated at sites near Hg sources. Overall, Hg concentrations in eggs from Cache Creek were lower than those reported in eggs of tree swallows (Tachycineta bicolor) from highly contaminated locations in North America. Total Hg concentrations were lower in all Cache Creek egg samples than adverse effects levels established for other species. Total Hg concentrations in bullfrogs (Rana catesbeiana) and foothill yellow-legged frogs (Rana boylii) collected from 10 of the study sites were both positively correlated with THg concentrations in cliff swallow eggs. Our data suggest that cliff swallows are reliable bioindicators of environmental Hg. ?? Springer Science+Business Media, LLC 2007.

  19. Evaluation of canoe surveys for anurans along the Rio Grande in Big Bend National Park, Texas

    Science.gov (United States)

    Jung, R.E.; Bonine, K.E.; Rosenshield, M.L.; de la Reza, A.; Raimondo, S.; Droege, S.

    2002-01-01

    Surveys for amphibians along large rivers pose monitoring and sampling problems. We used canoes at night to spotlight and listen for anurans along four stretches of the Rio Grande in Big Bend National Park, Texas, in 1998 and 1999. We explored temporal and spatial variation in amphibian counts and species richness and assessed relationships between amphibian counts and environmental variables, as well as amphibian-habitat associations along the banks of the Rio Grande. We documented seven anuran species, but Rio Grande leopard frogs (Rana berlandieri) accounted for 96% of the visual counts. Chorus surveys along the river detected similar or fewer numbers of species, but orders of magnitude fewer individuals compared to visual surveys. The number of species varied on average by 37% across monthly and nightly surveys. We found similar average coefficients of variation in counts of Rio Grande leopard frogs on monthly and nightly bases (CVs = 42-44%), suggesting that canoe surveys are a fairly precise technique for counts of this species. Numbers of Rio Grande leopard frogs observed were influenced by river gage levels and air and water temperatures, suggesting that surveys should be conducted under certain environmental conditions to maximize counts and maintain consistency. We found significant differences in species richness and bullfrog (Rana catesbeiana) counts among the four river stretches. Four rare anuran species were found along certain stretches but not others, which could represent either sampling error or unmeasured environmental or habitat differences among the river stretches. We found a greater association of Rio Grande leopard frogs with mud banks compared to rock or cliff (canyon) areas and with seepwillow and open areas compared to giant reed and other vegetation types. Canoe surveys appear to be a useful survey technique for anurans along the Rio Grande and may work for other large river systems as well.

  20. Comportamento alimentar e qualidade da água em tanques de criação de girinos de rã-touro Lithobates catesbeianus = Feeding behavior and water quality in tanks containing bullfrog tadpoles Lithobates catesbeianus

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Sipaúba-Tavares

    2008-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o comportamento alimentar e a qualidade da água em tanques de criação de girinos de rã-touro Lithobates catesbeianus durante 56 dias, a partir do estágio 25 da Tabela de Gosner (1960, criados em tanques de alvenaria comcapacidade de 1000 L. Os girinos que receberam ração (R e alga + plâncton + ração (APR apresentaram o melhor peso e sobrevivência, diferindo significativamente (p The objective of this study was to evaluate the effect of food treatments and water quality on the development of bullfrog tadpoles. The analysis, carried out in 1000 L tanks, was undertaken by weight and survival rates, during 56 days, as from stage 25 (Gosner, 1960. Treatments with ration (R and algae + plankton + ration (APR had the best results in weight and survival rates, which were significantly different (p < 0.05 from the other treatments, comprised of algae only or algae + plankton. Physical and chemical variables of water differed significantly (p < 0.05 during the experimental period and among treatments. There was a correlation between the concentration of species present in the food and in the tadpole digestive tract (rs = 0.39; p < 0.05. From the 14th dayof age, bullfrog tadpoles changed their feeding behavior, or rather, a search for food items other than plankton occurred. The utilization of combined natural and artificial (ration diets to feed bullfrog tadpoles was feasible and yielded a satisfactory development in theanimals.

  1. Critical electrolyte concentration of spermatozoal chromatin containing histone H1 variants

    Directory of Open Access Journals (Sweden)

    J.R.P. Falco

    1999-06-01

    Full Text Available The critical electrolyte concentrations (CEC of sperm chromatin from animal species known or suspected to contain histone H1 variants were compared by examining the affinity of their DNA-protein complexes for toluidine blue in the presence of Mg2+. Bullfrog, sea urchin, bee and bumblebee spermatozoa were studied. The CEC for Rana catesbeiana and two sea urchin species were similar to that of histone H5-containing chromatin from chicken erythrocytes, thus confirming the biochemical and structural similarities of these DNA-protein complexes. The CEC for bees and the bumblebee, Bombus atratus, showed no particular phylogenetic relationship. We concluded that the CEC of histone H1-containing sperm cell chromatin is a useful indicator of variability in DNA-protein complexes but is of little phylogenetic value.Valores de concentração crítica de eletrólitos (CEC da cromatina de espermatozóides de espécies conhecidas ou suspeitas de apresentarem variantes da histona H1 foram comparados entre si. O objetivo foi estabelecer semelhanças ou diferenças nos complexos DNA-proteína de espermatozóides dessas espécies em nível citoquímico. A afinidade por moléculas de azul de toluidina em condições de competição com íons Mg2+ foi investigada nos espermatozóides do sapo boi e de ouriços do mar, abelhas e mamangava. Uma íntima relação entre os valores de CEC de Rana catesbeiana e de duas espécies de ouriço do mar com os da cromatina de eritrócitos de frango, que contém a histona H5, foi vista estar de acordo com certas semelhanças bioquímicas e estruturais entre seus complexos DNA-proteína. Quanto aos dados para abelhas e para a mamangava Bombus atratus, não se pôde associar a variabilidade em valores de CEC com a posição das espécies na respectiva árvore filogenética. Conclui-se, portanto, que a CEC de cromatina de espermatozóides que contêm histona H1 é um indicador útil da influência de variantes de H1 na organiza

  2. Flavor improvement of Rana spinosa enzymatic hydrolysate%石蛙的酶解液化及风味改良

    Institute of Scientific and Technical Information of China (English)

    王瑞君

    2012-01-01

    Rana spinosa meat was hydrolyzed by papain and neutral protease. Lactic acid bacteria and rice wine yeasts were used to improve the flavor of the hydrolysate. Results indicate that neutral protease is superior to papain. The amount of amino nitrogen included in fermentation broth fermented by lactic acid bacteria is higher. The fermenting liquor from lactic acid bacteria flavor is better than that from rice wine yeast.%在酶适宜的环境条件下,利用木瓜蛋白酶与中性蛋白酶酶解石蛙肉及利用乳酸菌、黄酒酵母对酶解液进行风味改良。结果表明,中性蛋白酶对石蛙的水解效果较好,乳酸菌发酵液中氨态氮含量较高,乳酸菌发酵液风味改良效果优于黄酒酵母。

  3. Growth and developmental effects of coal combustion residues on Southern Leopard Frog (Rana sphenocephala) tadpoles exposed throughout metamorphosis

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, J.D.; Peterson, V.A.; Mendonca, M.T. [Auburn University, Auburn, AL (United States). Dept. for Biological Science

    2008-09-15

    The effects of aquatic deposition of coal combustion residues (CCRs) on amphibian life histories have been the focus of many recent studies. In summer 2005, we raised larval Southern Leopard Frogs, Rana sphenocephala, on either sand or CCR substrate (approximately 1 cm deep within plastic bins) and documented effects of sediment type on oral disc condition, as well as time to, mass at, and total body length at key developmental stages, including metamorphosis (Gosner stages (GS) 37, 42, and 46). We found no significant difference in mortality between the two treatments and mortality was relatively low (eight of 48 in the control group and four of 48 in the CCR group). Ninety percent of exposed tadpoles displayed oral disc abnormalities, while no control individuals displayed abnormalities. Tadpoles raised on CCR-contaminated sediment had decreased developmental rates and weighed significantly less at all developmental stages, on average, when compared to controls. The CCR treatment group was also significantly shorter In length than controls at the completion of metamorphosis (GS 46). Collectively, these findings are the most severe sub-lethal effects noted for any amphibian exposed to CCRs to date. More research is needed to understand how these long term effects may contribute to the dynamics of local amphibian populations.

  4. Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender

    Science.gov (United States)

    Chelgren, N.D.; Pearl, C.A.; Adams, M.J.; Bowerman, J.

    2008-01-01

    We used five years of recapture data and Bayesian estimation to assess seasonal survival, movement, and growth of Oregon Spotted Frogs (Rana pretiosa) relocated into created ponds at Dilman Meadow in Oregon, USA. We evaluate hypotheses specific to the relocation and elucidate aspects of R. pretiosa life history that are poorly known. The odds of survival of relocated individuals during the first year following relocation were 0.36 times the survival odds of relocated and non-relocated frogs after one year since the relocation. Survival rate was higher for large frogs. After accounting for frog size, we found little variation in survival between ponds at Dilman Meadow. Survival was lowest for males during the breeding/post-breeding redistribution period, suggesting a high cost of breeding for males. The highest survival rates occurred during winter for both genders, and one small spring was used heavily during winter but was used rarely during the rest of the year. Individual growth was higher in ponds that were not used for breeding, and increased with increasing pond age. Our study supports other evidence that R. pretiosa use different habitats seasonally and are specific in their overwintering habitat requirements. Because frogs were concentrated during winter, predator-free overwintering springs are likely to be of particular value for R. pretiosa populations. ?? 2008 by the American Society of Ichthyologists and Herpetologists.

  5. Biospectroscopy reveals the effect of varying water quality on tadpole tissues of the common frog (Rana temporaria).

    Science.gov (United States)

    Strong, Rebecca J; Halsall, Crispin J; Ferenčík, Martin; Jones, Kevin C; Shore, Richard F; Martin, Francis L

    2016-06-01

    Amphibians are undergoing large population declines in many regions around the world. As environmental pollution from both agricultural and urban sources has been implicated in such declines, there is a need for a biomonitoring approach to study potential impacts on this vulnerable class of organism. This study assessed the use of infrared (IR) spectroscopy as a tool to detect changes in several tissues (liver, muscle, kidney, heart and skin) of late-stage common frog (Rana temporaria) tadpoles collected from ponds with differing water quality. Small differences in spectral signatures were revealed between a rural agricultural pond and an urban pond receiving wastewater and landfill run-off; these were limited to the liver and heart, although large differences in body size were apparent, surprisingly with tadpoles from the urban site larger than those from the rural site. Large differences in liver spectra were found between tadpoles from the pesticide and nutrient impacted pond compared to the rural agricultural pond, particularly in regions associated with lipids. Liver mass and hepatosomatic indices were found to be significantly increased in tadpoles from the site impacted by pesticides and trace organic chemicals, suggestive of exposure to environmental contamination. Significant alterations were also found in muscle tissue between tadpoles from these two ponds in regions associated with glycogen, potentially indicative of a stress response. This study highlights the use of IR spectroscopy, a low-cost, rapid and reagent-free technique in the biomonitoring of a class of organisms susceptible to environmental degradation. PMID:26925755

  6. Characterization of the Skin Microbiota in Italian Stream Frogs (Rana italica) Infected and Uninfected by a Cutaneous Parasitic Disease.

    Science.gov (United States)

    Federici, Ermanno; Rossi, Roberta; Fidati, Laura; Paracucchi, Romina; Scargetta, Silvia; Montalbani, Elena; Franzetti, Andrea; La Porta, Gianandrea; Fagotti, Anna; Simonceli, Francesca; Cenci, Giovanni; Di Rosa, Ines

    2015-01-01

    In human and wildlife populations, the natural microbiota plays an important role in health maintenance and the prevention of emerging infectious diseases. In amphibians, infectious diseases have been closely associated with population decline and extinction worldwide. Skin symbiont communities have been suggested as one of the factors driving the different susceptibilities of amphibians to diseases. The activity of the skin microbiota of amphibians against fungal pathogens, such as Batrachochytrium dendrobatidis, has been examined extensively, whereas its protective role towards the cutaneous infectious diseases caused by Amphibiocystidium parasites has not yet been elucidated in detail. In the present study, we investigated, for the first time, the cutaneous microbiota of the Italian stream frog (Rana italica) and characterized the microbial assemblages of frogs uninfected and infected by Amphibiocystidium using the Illumina next-generation sequencing of 16S rRNA gene fragments. A total of 629 different OTUs belonging to 16 different phyla were detected. Bacterial populations shared by all individuals represented only one fifth of all OTUs and were dominated by a small number of OTUs. Statistical analyses based on Bray-Curtis distances showed that uninfected and infected specimens had distinct cutaneous bacterial community structures. Phylotypes belonging to the genera Janthinobacterium, Pseudomonas, and Flavobacterium were more abundant, and sometimes almost exclusively present, in uninfected than in infected specimens. These bacterial populations, known to exhibit antifungal activity in amphibians, may also play a role in protection against cutaneous infectious diseases caused by Amphibiocystidium parasites. PMID:26370166

  7. Evolutionary dynamics of a rapidly receding southern range boundary in the threatened California red-legged frog (Rana draytonii)

    Science.gov (United States)

    Richmond, Jonathan Q.; Barr, Kelly R.; Backlin, Adam R.; Vandergast, Amy G.; Fisher, Robert N.

    2013-01-01

    Populations forming the edge of a species range are often imperiled by isolation and low genetic diversity, with proximity to human population centers being a major determinant of edge stability in modern landscapes. Since the 1960s, the California red-legged frog (Rana draytonii) has undergone extensive declines in heavily urbanized southern California, where the range edge has rapidly contracted northward while shifting its cardinal orientation to an east-west trending axis. We studied the genetic structure and diversity of these frontline populations, tested for signatures of contemporary disturbance, specifically fire, and attempted to disentangle these signals from demographic events extending deeper into the past. Consistent with the genetic expectations of the ‘abundant-center’ model, we found that diversity, admixture, and opportunity for random mating increases in populations sampled successively further away from the range boundary. Demographic simulations indicate that bottlenecks in peripheral isolates are associated with processes extending tens to a few hundred generations in the past, despite the demographic collapse of some due to recent fire-flood events. While the effects of recent disturbance have left little genetic imprint on these populations, they likely contribute to an extinction debt that will lead to continued range contraction unless management intervenes to stall or reverse the process.

  8. Predator mediated selection and the impact of developmental stage on viability in wood frog tadpoles (Rana sylvatica

    Directory of Open Access Journals (Sweden)

    Calsbeek Ryan

    2011-12-01

    Full Text Available Abstract Background Complex life histories require adaptation of a single organism for multiple ecological niches. Transitions between life stages, however, may expose individuals to an increased risk of mortality, as the process of metamorphosis typically includes developmental stages that function relatively poorly in both the pre- and post-metamorphic habitat. We studied predator-mediated selection on tadpoles of the wood frog, Rana sylvatica, to identify this hypothesized period of differential predation risk and estimate its ontogenetic onset. We reared tadpoles in replicated mesocosms in the presence of the larval odonate Anax junius, a known tadpole predator. Results The probability of tadpole survival increased with increasing age and size, but declined steeply at the point in development where hind limbs began to erupt from the body wall. Selection gradient analyses indicate that natural selection favored tadpoles with short, deep tail fins. Tadpoles resorb their tails as they progress toward metamorphosis, which may have led to the observed decrease in survivorship. Path models revealed that selection acted directly on tail morphology, rather than through its indirect influence on swimming performance. Conclusions This is consistent with the hypothesis that tail morphology influences predation rates by reducing the probability a predator strikes the head or body.

  9. Long-term effects of pesticide exposure at various life stages of the southern leopard frog (Rana sphenocephala)

    Science.gov (United States)

    Bridges, C.M.

    2000-01-01

    Amphibian larvae are commonly exposed to low levels of pesticides during their development. Chronic studies generally examine the effects of long-term exposure, but they often disregard the importance of the individual life stage at which tadpoles are exposed. I determined the point during development at which carbaryl effects are manifested by exposing southern leopard frog tadpoles (Rana sphenocephala) to the pesticide carbaryl at five different times during development. Metamorphs exposed throughout the tadpole stage and throughout development (egg, embryo, tadpole) experienced significant mortality at all chemical levels. Although the length of the larval period was the same for all experimental groups, metamorphs exposed during the egg stage were smaller than their corresponding controls, independent of whether they were exposed at any other stage. Nearly 18% of individuals exposed to carbaryl during development exhibited some type of developmental deformity (including both visceral and limb malformities), compared to a single deformed (exposure to nonpersistent chemicals may last for only a short period of time, it is important to examine the long-term effects that short-term exposure has on larval amphibians and the existence of any sensitive life stage. Any delay in metamorphosis or decrease in size at metamorphosis can impact demographic processes of the population, potentially leading to declines or local extinction.

  10. Conservation genetics of evolutionary lineages of the endangered mountain yellow-legged frog, Rana muscosa (Amphibia: Ranidae), in southern California

    Science.gov (United States)

    Schoville, Sean D.; Tustall, Tate S.; Vredenburg, Vance T.; Backlin, Adam R.; Gallegos, Elizabeth; Wood, Dustin A.; Fisher, Robert N.

    2011-01-01

    Severe population declines led to the listing of southern California Rana muscosa (Ranidae) as endangered in 2002. Nine small populations inhabit watersheds in three isolated mountain ranges, the San Gabriel, San Bernardino and San Jacinto. One population from the Dark Canyon tributary in the San Jacinto Mountains has been used to establish a captive breeding population at the San Diego Zoo Institute for Conservation Research. Because these populations may still be declining, it is critical to gather information on how genetic variation is structured in these populations and what historical inter-population connectivity existed between populations. Additionally, it is not clear whether these populations are rapidly losing genetic diversity due to population bottlenecks. Using mitochondrial and microsatellite data, we examine patterns of genetic variation in southern California and one of the last remaining populations of R. muscosa in the southern Sierra Nevada. We find low levels of genetic variation within each population and evidence of genetic bottlenecks. Additionally, substantial population structure is evident, suggesting a high degree of historical isolation within and between mountain ranges. Based on estimates from a multi-population isolation with migration analysis, these populations diversified during glacial episodes of the Pleistocene, with little gene flow during population divergence. Our data demonstrate that unique evolutionary lineages of R. muscosa occupy each mountain range in southern California and should be managed separately. The captive breeding program at Dark Canyon is promising, although mitigating the loss of neutral genetic diversity relative to the natural population might require additional breeding frogs.

  11. Nestedness in colonization-dominated systems: helminth infracommunities of Rana vaillanti Brocchi (Anura: Ranidae) in Los Tuxtlas, Veracruz, Mexico.

    Science.gov (United States)

    Zelmer, Derek A; Paredes-Calderón, Laura; León-Règagnon, Virginia; García-Prieto, Luis

    2004-08-01

    Colonization probabilities of parasite species often are determined by the habitat preference and vagility of host individuals. Although extinction-based interpretations have been investigated for nested subset patterns of parasite infracommunities, the low relative frequency of nestedness in colonization-dominated systems makes the determination and interpretation of nested infracommunities of broad ecological importance. In these systems, ontogenetic shifts in habitat preference or diet of the host have the potential to produce nested subset patterns of parasite infracommunities. Helminth infracommunity structure was investigated for 76 Rana vaillanti individuals collected from Laguna Escondida, Los Tuxtlas, Veracruz, Mexico, in 1998. Pooled helminth infracommunities were significantly nested, as were penetrating and ingested helminth infracommunities when considered separately. Richness, diversity, and evenness of the helminth infracommunities were not correlated with host size, and did not differ between host sexes, suggesting that the structure of infracommunities simply is a product of the interaction between host individuals and their landscape mediated by individual differences in vagility. It is hypothesized that individual differences in recruitment can produce nested subset infracommunity patterns when the habitats or habitat preferences of hosts are themselves nested. PMID:15357057

  12. Electrospun poly(l-lactide)/zein nanofiber mats loaded with Rana chensinensis skin peptides for wound dressing.

    Science.gov (United States)

    Zhang, Mei; Li, Xueqi; Li, Siming; Liu, Yongjia; Hao, Linlin

    2016-09-01

    Electrospun nanofiber mats can display impressive performance as an ideal wound dressing. In this study, poly(l-lactide)(PLLA)/zein nanofiber mats loaded with Rana chensinensis skin peptides (RCSPs) were successfully produced by two different electrospinning techniques, blend and coaxial, with the goal of developing a wound dressing material. The nanofiber mats were investigated by environmental scanning electron microscope (ESEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), water contact angle, mechanical tests and cell viability. The resulting nanofiber mats exhibited smooth surfaces, tiny diameters and different cross-sectional shapes from pure PLLA and zein nanofibers. The FTIR result showed that PLLA, zein and RCSPs were well dispersed, without chemical interactions. Compared with coaxial nanofiber mats, blending zein-RCSPs with PLLA enhanced hydrophilicity but decreased mechanical properties. Adding RCSPs into the electrospun nanofibers significantly improved the mechanical properties of the mats. Cell viability studies with human foreskin fibroblasts demonstrated that cell growth on PLLA/zein-RCSPs nanofiber mats was significantly higher than that on PLLA/zein nanofiber mats. The results indicate that nanofiber mats containing RCSPs are potential candidates for wound dressing. PMID:27432415

  13. Geographical variation and sexual differences of body length and age composition in Rana temporaria: the ontogenetic development and phenotypic trends

    Directory of Open Access Journals (Sweden)

    Lyapkov Sergey

    2012-06-01

    Full Text Available The analysis of literature data on the mean values of age and body length of adult individuals of widespread species Rana temporaria from about 70 spatially separated populations, including our published data, was conducted. The evident trend in population mean age increase with the decrease of the of activity season length was revealed as well as the absence of that trend in the mean body length, with the maximal mean value in body length being near central part of the range. Our explanation of non-linear trend in the mean values of body length does not contradict other models of geographic variability explaining the correspondence and discrepance with the Bergman rule. In addition our explanation corresponds to the revealed features of interpopulation variation in growth rate. The revealed trend of variation in the mean body length is resulted from both growth rate decrease and mean age increase with the decrease in the length of activity season. The relatively low mean values of body length in populations from south and southern-west borders of the range are explained not only by low mean age but by lower growth rate despite high length of activity season. The interpopulation variation in body length is determined not only by body length but by age composition differences both between and within population. Therefore, the direction and intensity of sexual differences have not distinct trends, and the correspondence to Rensch rule (in contrast to Bergman rule is rarely observed.

  14. Nueva especie de rana del género Pristimantis del grupo lacrimosus (Amphibia: Craugastoridae del Parque Nacional Sangay, Ecuador

    Directory of Open Access Journals (Sweden)

    Diego Batallas R.

    2014-01-01

    Full Text Available Describimos una nueva especie de rana terrestre del genero Pristimantis de tamaño mediano (LRC en machos desde 22.18 a 25.13 mm descubierta en los bosques nublados de las estribaciones orientales del Parque Nacional Sangay, al centro oriente de Ecuador, a elevaciones de 2750 m. Asignamos a Pristimantis latericius sp. nov., al grupo Pristimantis lacrimosus, el cual se diferencia del resto de miembros de este grupo por presentar tubérculos prominentes en el parpado superior y una coloración rojo anaranjado en el dorso. Las llamadas son cortas, conformadas por una sola nota y dos bandas armónicas. Importantes levantamientos de información faunística se han venido generando en los últimos años en el Parque Nacional Sangay, sin embargo es necesario incrementar estudios que ayuden a documentar la ecología e historia natural de los anfibios, ya que sin lugar a dudas ayudaran a comprender procesos ecológicos. El descubrimiento de esta y otras nuevas especies en este sector, demuestra su importancia biológica confortando al desarrollo de planes de conservación en este importante Patrimonio Natural de la Humanidad.

  15. Odorous and non-fatal skin secretion of adult wrinkled frog (Rana rugosa is effective in avoiding predation by snakes.

    Directory of Open Access Journals (Sweden)

    Yuri Yoshimura

    Full Text Available The roles played by nonfatal secretions of adult anurans in the avoidance of predation remain unknown. The adult Wrinkled frog (Rana rugosa has warty skin with the odorous mucus secretion that is not fatal to the snake Elaphe quadrivirgata. We fed R. rugosa or Fejervarya limnocharis, which resembles R. rugosa in appearance and has mucus secretion, to snakes and compared the snakes' responses to the frogs. Compared to F. limnocharis, R. rugosa was less frequently bitten or swallowed by snakes. The snakes that bit R. rugosa spat out the frogs and showed mouth opening (gaping behavior, while the snakes that bit F. limnocharis did not show gaping behavior. We also compared the responses of the snakes to R. rugosa and F. limnocharis secretions. We coated palatable R. japonica with secretions from R. rugosa or F. limnocharis. The frogs coated by R. rugosa secretion were less frequently bitten or swallowed than those coated by F. limnocharis secretion. We concluded that compared to different frog species of similar sizes, the adult R. rugosa was less frequently preyed upon by, and that its skin secretion was effective in avoiding predation by snakes.

  16. 虎纹蛙的人工养殖技术%Artificial Culture Technique for Rana tigrina rugulosa

    Institute of Scientific and Technical Information of China (English)

    黄志平

    2006-01-01

    虎纹蛙(Rana tigrina rugulosa Wiegmann)属两栖纲、无尾目、蛙科、虎纹蛙属,又称水鸡、田鸡等,为国家二级保护野生动物。虎纹蛙在我国分布很广,遍布长江以南各省区,由于其营养丰富、肉质鲜美,历来是人们喜受的美味佳肴,在市场上很受欢迎。多年来,由于捕捉过度,加上种植水稻、蔬菜时使用农药,导致野生虎纹蛙数量锐减。为保护虎纹蛙的自然资源,满足市场需求,开展其人工养殖具有重要的现实意义。福建省光泽县于1999年开始研究虎纹蛙的人工养殖技术,现已取得试验成功并投人规模化生产,并将此项技术推广到全县及周边地区。

  17. Histology of Visual Organ in Rana rugulosa%虎纹蛙视觉器官组织学研究

    Institute of Scientific and Technical Information of China (English)

    江剑平; 黄键; 陈文列; 黄浩; 林玮

    2001-01-01

    用光镜和电镜观察了虎纹蛙(Rana rugulosa)眼球的组织结构,同时测量了其眼球的一些视参数.虎纹蛙眼球呈圆球形.角膜内未见前界膜;虹膜内可见少量括约肌,但未见扩瞳肌纤维;虹膜的内侧面有许多突起;巩膜有完整的半球形软骨;晶状体环垫薄,因而视觉调节能力很弱.视网膜中视细胞由视杆细胞、视锥细胞组成,其中视杆细胞占多数.视细胞与神经节细胞数量之比为3.68∶1.以上表明虎纹蛙的眼球组织结构与其弱光视觉和捕食习性相适应.

  18. 虎纹蛙(RANA RUGULOSA)视网膜结构与环境适应性的研究%STUDIES ON RETINAL STRUCTURE OF RANA RUGULOSA AND ITS E NVIRONMENTAL ADAPTATION

    Institute of Scientific and Technical Information of China (English)

    江剑平; 陈文列; 余望; 黄键; 钟秀容

    2001-01-01

    在光镜和电镜下观察了虎纹蛙(Rana rugulosa)视网膜的 组织结构,着重探讨了色素细胞和视细胞的形态结构.视网膜中三个核层及两个网状层分布 均匀,无中央凹.色素细胞内含有大量的脂滴、色素颗粒、髓样体和形状各异的溶酶体等.视 细胞由视杆细胞和视锥细胞组成,视杆细胞占多数.在视网膜中央区,视杆细胞数与视锥细 胞数之比为1:1;在周缘区,两者数量之比为3:1.视杆细胞外段呈高柱状,体积远远大于 视锥细胞外段,肌样体内有大量的微管.视锥细胞外段呈矮锥形,椭圆体内有一球状小体.视 细胞与节细胞数量之比为3.68:1.结果表明,虎纹蛙视网膜结构特征与其生活于田间、山涧 等弱光环境和捕食习性是相适应的. 图版1(图1~图10) 表2 参14%The retinal structure in Rana rugulosa was studied using light an d electron microscope, and the structure of pigment cells and visual cells was a lso studied. The three nuclear layers and the two plexiform layers are evenly di spersed in the retina. No forea centralis is founded. There are many lipoids, ly sosomes, myeloids and granular melanins in the pigment epithelial cells. There a re rods and cones in the retina, and the rods are predominant. The ratio of rods to cones is about 1:1 in the center, and about 3:1 in the periphery. Outer segm ent of rods is high cylinder, and its volume is bigger than that of cone. There are many microtubes around the myoid of rods. Outer segment of cones is low cone , a globule is localized in each ellipsoid of the cones. Th e ratio of the visual cells to the ganglion cells is about 3.68:1.This study sho wed that the histological structure of retina in R. rugulosa is principally adapted to low intensity of light and hunting for food. Plate 1 (Fig 1 ~10), Tab 2, Ref 14

  19. Complex patterns of geographic variation in heat tolerance and Hsp70 expression levels in the common frog Rana temporaria

    DEFF Research Database (Denmark)

    Sørensen, Jesper Givskov; Pekkonen, Minna; Lindgren, Beatrice; Loeschcke, Volker; Laurila, Anssi; Merilä, Juha

    2009-01-01

    1. We tested for geographical variation in heat tolerance and Hsp70 expression levels of Rana temporaria tadpoles along a 1500 km long latitudinal gradient in Sweden.   2. Temperature tolerance of the hatchling tadpoles did not differ among populations, but they tolerated stressful hot temperatures...... stressful temperature (36 °C) the northern population showed highest tolerance. 4. The heat shock pre-treatment increased heat tolerance of the tadpoles. The possible adaptive role of Hsp70 for thermal tolerance and climatic adaptation in R. temporaria tadpoles is discussed....

  20. Comparación de la respuesta auditiva del tallo cerebral entre Rana catesbiana (Anura: Ranidae) y Sceloporus torcuatus (Sauria: Phrynosomatida)

    OpenAIRE

    Jos\\u00E9 De Jes\\u00FAs Morales Mart\\u00EDnez; Hugo Sol\\u00EDs Ort\\u00EDz

    1999-01-01

    En general se conoce muy poco sobre el sentido de la audición de los anfibios y de los reptiles. El órgano auditivo ha sufrido cambios evolutivos que se relacionan con la transición del medio acuático al terrestre. Por esta razón, los reptiles terrestres muestran aparentemente un sistema auditivo eficiente en comparación con los anfibios. El presente estudio se llevó a cabo con el fin de comparar las respuestas auditivas entre Rana catesbiana y Sceloporus torquatus. Se utilizó la ...

  1. Comparación de la respuesta auditiva del tallo cerebral entre Rana catesbiana (Anura: Ranidae) y Sceloporus torcuatus (Sauria: Phrynosomatida)

    OpenAIRE

    José De Jesús Morales Martínez; Hugo Solís Ortíz

    1999-01-01

    En general se conoce muy poco sobre el sentido de la audición de los anfibios y de los reptiles. El órgano auditivo ha sufrido cambios evolutivos que se relacionan con la transición del medio acuático al terrestre. Por esta razón, los reptiles terrestres muestran aparentemente un sistema auditivo eficiente en comparación con los anfibios. El presente estudio se llevó a cabo con el fin de comparar las respuestas auditivas entre Rana catesbiana y Sceloporus torquatus. Se utilizó la técnica de l...

  2. Effects of Bisphenol A on apoptosis of spermatogenic cells and expression of Bax and Bcl-2 proteins in the Siberian frog Rana chensinensis

    OpenAIRE

    LIN Sheng-Nan; Zhang, Yu-hui

    2008-01-01

    In order to investigate the effects of bisphenol A (BPA) on apoptosis and the expression levels of Bax and Bcl-2 protein in amphibian spermatogenic cells, we treated Rana chensinensis with concentrations of 10-7, 10-6, 10-5mol/L BPA respectively. Testes were removed after R.chensinensis had been treated for 3 , 5 or 7 days. Apoptotic cells were examined by TUNEL and Methyl Green-Pyronine. The expression levels of Bax and Bcl-2 protein in spermatogenic cells were detected by immunohistochemic...

  3. Una nueva especie de rana terrestre del género Pristimantis (Amphibia: Craugastoridae), de la Cordillera de Kutukú, Ecuador

    OpenAIRE

    Jorge Brito M.; Glenda Pozo-Zamora

    2013-01-01

    Describimos una especie nueva de mediano tamaño (LRC en la hembra 38.7 mm; en machos de 23.8 a 26.4 mm) de rana terrestre del género Pristimantis de los bosques sub-tropicales de la Cordillera de Kutukú, del sureste de Ecuador, a elevaciones de 1581-1820 m. Asignamos a Pristimantis almendariz sp. nov., al subgénero Hypodictyon, serie de especies ridens. La nueva especie difiere de otros miembros de la serie ridens por su patrón distintivo con manchas dorsales, membrana timpánica ausente, pres...

  4. Nueva especie de rana terrestre del género Pristimantis (Amphibia: Craugastoridae), meseta de la Dordillera del Cóndor

    OpenAIRE

    Jorge Brito M.; Diego Batallas R.; David Velalcázar

    2014-01-01

    Describimos una especie nueva, de mediano tamaño (LRC en la hembra 21.7-24.9 mm; en machos 15.2-17.8 mm), de rana terrestre del género Pristimantis proveniente de la meseta de arenisca de la Cordillera del Cóndor, del sureste de Ecuador, con una elevacion de 2300 m. La nueva especie difiere de sus congéneres presentes en Ecuador por su patrón distintivo de coloración, superficie dorsal pardo ocráceo con numerosas manchas amarillentas, membrana timpánica presente, dedos pediales y manuales cor...

  5. 虎纹蛙肢体超常再生和畸变二例%Limb's Extra Regeneration and Malformation of Two Rana tigrina rugulosa

    Institute of Scientific and Technical Information of China (English)

    林植华; 张春牛; 雷焕宗; 郎法勇

    2002-01-01

    对二例虎纹蛙(Rana tigrina rugulosa)肢体超常再生和畸变进行报道和研究.虎纹蛙肢体超常再生和畸变现象的原因可能是变态发育过程中外界创伤的刺激导致组织增生和超常肢体的出现,也可能因农药的使用和"三废"导致环境污染引起变异的发生和超常肢体的出现.

  6. Chemopreventive Effect of Cinnamon Extract on Carbon Tetrachloride-Induced Physiological Changes in the Frog, Rana ridibunda

    Science.gov (United States)

    Al-Attar, Atef M.

    The present study examined the preventive influences of an aqueous extract of cinnamon on carbon tetrachloride-induced some physiological alterations in the frog, Rana ridibunda. The experimental animals were divided into five batches. The first batch was untreated and served as control. The other batches were treated for 6 weeks with carbon tetrachloride, cinnamon extract plus carbon tetrachloride, cinnamon and corn oil, respectively. Haematological, biochemical and hepatosomatic index indices were chosen as physiological indicators. These parameters were evaluated at 2, 4 and 6 weeks. In comparison with control and cinnamon plus CCl4 batches, significant decreases of red blood cell count, haemoglobin concentration, haematocrit, mean corpuscular haemoglobin concentration and increases of glutamic pyruvic acid transaminase values were noted in CCl4-exposed batch at all experimental periods. Also, glutamic oxaloacetic acid transaminase and hepatosomatic index levels were significantly elevated, while mean corpuscular haemoglobin values were decreased at second and last periods. Mean cell volume values were only increased at the first period. In comparison with control batch, significant decreases of red blood cell count, haemoglobin concentration, haematocrit, and increases of glutamic oxaloacetic acid transaminase, glutamic pyruvic acid transaminase and hepatosomatic index values were observed in frogs treated with cinnamon plus CCl4 at 2 and 6 weeks. Mean cell volume and mean corpuscular haemoglobin values were statistically elevated at second period. Mean corpuscular haemoglobin concentration values were declined at last period. Moreover, the percentage changes of these parameters in cinnamon plus CCl4 batch tended to be lower than CCl4 treated the experimental animals. In addition, it is conceivable therefore, that the cinnamon aqueous extract exhibits a protective influence against carbon tetrachloride-induced some physiological changes, probably mediated

  7. Daz- and pumilio-like genes are asymmetrically localized in Pelophylax (Rana) oocytes and are expressed during early spermatogenesis.

    Science.gov (United States)

    Marracci, Silvia; Michelotti, Valentina; Casola, Claudio; Giacoma, Cristina; Ragghianti, Matilde

    2011-07-15

    In many organisms, the specification of cell fate and the formation of embryonic axes depend on a proper distribution of maternal mRNAs during oogenesis. Asymmetrically localized determinants are required both for embryonic axes and germline determination in anuran amphibians. As a model system of these processes, we have used a species complex of the genus Pelophylax (Rana), characterized by a hybridogenetic reproduction that involves events of genome exclusion and endoreduplication during meiosis in both sexes. With the aim of characterizing the still largely unknown molecular events regulating Pelophylax gametogenesis, we have isolated in this animal model homologues of the deleted in AZoospermia-like (DAZl) and pumilio gene families (named RlDazl and RlPum1, respectively), which encode posttranscriptional regulators. Expression pattern analysis of these genes showed that RlDazl is exclusively expressed in gonadal tissues, whereas RlPum1 is expressed in both somatic tissues and gonads. In situ hybridization carried out on gonads revealed that the two transcripts were asymmetrically localized along the animal-vegetal (A-V) axis of oocytes. In particular, the RlDazl transcript progressively collected to the vegetal pole during oogenesis, whereas the RlPum1 mRNA was preferentially enriched at the animal hemisphere. In adult testes, RlDazl and RlPum1 were expressed in specific phases of spermatogenetic divisions as shown by immunostaining with anti-H3 phosphohistone antibody. Our results indicate that RlDazl and RlPum1 represent two early indicators of oocyte polarity in this hybridogenetic vertebrate model. Additionally, RlDazl share with vertebrate DAZ- like genes a germ cell-specific expression pattern. PMID:21344644

  8. Temporal occurrence and community structure of helminth parasites in southern leopard frogs, Rana sphenocephala, from north central Oklahoma.

    Science.gov (United States)

    Vhora, M Suhail; Bolek, Matthew G

    2015-03-01

    Currently, little information is available about the temporal recruitment of helminth communities in amphibian hosts. We examined the helminth community structure and temporal recruitment of helminth parasites in southern leopard frogs, Rana sphenocephala. Specifically, we were interested in how host life history such as habitat, age and/or size, diet, sex, and temporal variation in abiotic factors (precipitation and temperature) were important in determining monthly infection patterns of helminth populations and communities in southern leopard frogs. From May to September 2011, 74 southern leopard frogs were collected from Teal Ridge in Stillwater Payne County, OK, USA. Sixty-nine (93 %) of 74 frogs were infected with 1 or more helminth species. During our collecting period, the average monthly temperature was lowest in May and highest in July, and monthly precipitation was highest in May and lowest during the first week of September. The component community consisted of 11 species of helminth, including 1 larval and 1 adult cestode, 2 larval and 3 adult trematodes, and 1 juvenile and 3 adult nematodes. Of the 1790 helminths recovered, 51 % (911) were nematodes, 47 % (842) were cestodes, and 2 % (37) were trematodes. There were significant differences in the total abundance and mean species richness of helminths acquired by skin contact or through frog diet in monthly component communities of southern leopard frogs. A positive correlation existed for percentage of all helminths acquired by skin contact and monthly precipitation (r = 0.94, P < 0.01). Conversely, a negative correlation existed for monthly precipitation and percentage of helminths acquired by diet (r = -0.94, P < 0.01). Our results indicate that abiotic conditions such as precipitation have a major influence on the avenues for and constraints on the transmission of helminths with life cycles associated with water/moisture or terrestrial intermediate/paratenic hosts and are important in structuring

  9. Anti-apoptotic response during anoxia and recovery in a freeze-tolerant wood frog (Rana sylvatica)

    Science.gov (United States)

    Gerber, Victoria E.M.; Wijenayake, Sanoji

    2016-01-01

    The common wood frog, Rana sylvatica, utilizes freeze tolerance as a means of winter survival. Concealed beneath a layer of leaf litter and blanketed by snow, these frogs withstand subzero temperatures by allowing approximately 65–70% of total body water to freeze. Freezing is generally considered to be an ischemic event in which the blood oxygen supply is impeded and may lead to low levels of ATP production and exposure to oxidative stress. Therefore, it is as important to selectively upregulate cytoprotective mechanisms such as the heat shock protein (HSP) response and expression of antioxidants as it is to shut down majority of ATP consuming processes in the cell. The objective of this study was to investigate another probable cytoprotective mechanism, anti-apoptosis during oxygen deprivation and recovery in the anoxia tolerant wood frog. In particular, relative protein expression levels of two important apoptotic regulator proteins, Bax and p-p53 (S46), and five anti-apoptotic/pro-survival proteins, Bcl-2, p-Bcl-2 (S70), Bcl-xL, x-IAP, and c-IAP in response to normoxic, 24 Hr anoxic exposure, and 4 Hr recovery stages were assessed in the liver and skeletal muscle using western immunoblotting. The results suggest a tissue-specific regulation of the anti-apoptotic pathway in the wood frog, where both liver and skeletal muscle shows an overall decrease in apoptosis and an increase in cell survival. This type of cytoprotective mechanism could be aimed at preserving the existing cellular components during long-term anoxia and oxygen recovery phases in the wood frog. PMID:27042393

  10. Histopathological changes and erythrocytic nuclear abnormalities in Iberian green frogs (Rana perezi Seoane) from a uranium mine pond

    Energy Technology Data Exchange (ETDEWEB)

    Marques, S.M. [Departamento de Biologia/Centro de Estudos do Ambiente e do Mar (CESAM), Campus de Santiago, Universidade de Aveiro, 3810-193 Aveiro (Portugal)], E-mail: s.reis.marques@gmail.com; Antunes, S.C. [Departamento de Biologia/Centro de Estudos do Ambiente e do Mar (CESAM), Campus de Santiago, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Pissarra, H. [Laboratorio de Anatomia Patologica, Centro de Investigacao Interdisciplinar em Sanidade Animal (CIISA), Faculdade de Medicina Veterinaria, U.T.L., Lisboa (Portugal); Pereira, M.L. [Departamento de Biologia/Centro de Investigacao em Materiais Ceramicos e Compositos (CICECO), Campus de Santiago, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Goncalves, F.; Pereira, R. [Departamento de Biologia/Centro de Estudos do Ambiente e do Mar (CESAM), Campus de Santiago, Universidade de Aveiro, 3810-193 Aveiro (Portugal)

    2009-01-31

    In spite of their sensitivity to anthropogenic stressors, adults of Rana perezi Seoane were found inhabiting effluent ponds from a uranium mine. Due to the presence of such organisms in this environment, it becomes of paramount importance to assess the damages induced by local contamination on these aquatic vertebrates, in order to integrate this information on a site-specific risk assessment that is being carried out in the area. To attain this purpose an ethically and statistically acceptable number of green frogs were captured in the mine pond (M) and in a pristine river (VR), a few kilometres from the mine. Bioaccumulation of metals and histopathological alterations were evaluated in the liver, kidneys, spleen, lungs and testes of the animals. Simultaneously, blood samples were collected for the evaluation of genotoxic damage on erythrocytes. Animals captured in the M pond showed significantly increased levels of Be, Al, Mn, Fe and U in the liver, as well as Pb and U in the kidney. The liver was the main target organ for the bioaccumulation of Be, Al, Fe and U. However, renal histopathologies were more severe than those of liver. The main tissue alterations recorded in animals from the mine were: a slight increase in melanomacrophagic centers (MMC) in liver, lung and kidneys; dilatation of the renal tubules lumen associated with tubular necrosis. A significantly higher number of erythrocytic abnormalities (lobed, notched and kidney shaped nuclei and micronuclei) were recorded in frogs from M than in frogs from VR, along with a significantly lower frequency of immature erythrocytes. Both observations suggested that the removal of abnormal blood cells might be compromised.

  11. Endocrine-disrupting effects and reproductive toxicity of low dose MCLR on male frogs (Rana nigromaculata) in vivo

    International Nuclear Information System (INIS)

    Highlights: • Low-dose MCLR (1 μg/L) elicits a potential ecological effect on amphibian populations. • MCLR can induce abnormal sperm morphologies and activities on male frogs. • MCLR can induce a decrease in serum testosterone and an increase in serum estradiol of male frogs. • MCLR can increase SF-1 protein levels and decrease P450 aromatase levels in the gonads of frogs. - Abstract: Toxic cyanobacterial blooms are potential global threats to aquatic ecosystems and human health. The World Health Organization has set a provisional guideline limit of 1 μg/L microcystin-LR (MCLR) in freshwater. However, MCLR concentrations in several water bodies have exceeded this level. Despite this recommended human safety standard, MCLR-induced endocrine-disrupting effects and reproductive toxicity on male frog (Rana nigromaculata) were demonstrated in this study. Results showed that sperm motility and sperm count were significantly and negatively correlated with exposure time and concentration. By contrast, abnormal sperm rate was positively correlated with both parameters. Ultrastructural observation results revealed abnormal sperm morphologies, vacuoles in spermatogenic cells, cell dispersion, incomplete cell structures, and deformed nucleoli. These results indicated that MCLR could induce toxic effects on the reproductive system of frogs, significantly decrease testosterone content, and rapidly increase estradiol content. Prolonged exposure and increased concentration enhanced the relative expression levels of P450 aromatase and steroidogenic factor 1; thus, endocrine function in frogs was disrupted. This study is the first to demonstrate in vivo MCLR toxicity in the reproductive system of male R. nigromaculata. This study provided a scientific basis of the global decline in amphibian populations

  12. Endocrine-disrupting effects and reproductive toxicity of low dose MCLR on male frogs (Rana nigromaculata) in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Xiuying; Cai, Chenchen; Wang, Jia; Gao, Nana; Zhang, Hangjun, E-mail: zhanghangjun@gmail.com

    2014-10-15

    Highlights: • Low-dose MCLR (1 μg/L) elicits a potential ecological effect on amphibian populations. • MCLR can induce abnormal sperm morphologies and activities on male frogs. • MCLR can induce a decrease in serum testosterone and an increase in serum estradiol of male frogs. • MCLR can increase SF-1 protein levels and decrease P450 aromatase levels in the gonads of frogs. - Abstract: Toxic cyanobacterial blooms are potential global threats to aquatic ecosystems and human health. The World Health Organization has set a provisional guideline limit of 1 μg/L microcystin-LR (MCLR) in freshwater. However, MCLR concentrations in several water bodies have exceeded this level. Despite this recommended human safety standard, MCLR-induced endocrine-disrupting effects and reproductive toxicity on male frog (Rana nigromaculata) were demonstrated in this study. Results showed that sperm motility and sperm count were significantly and negatively correlated with exposure time and concentration. By contrast, abnormal sperm rate was positively correlated with both parameters. Ultrastructural observation results revealed abnormal sperm morphologies, vacuoles in spermatogenic cells, cell dispersion, incomplete cell structures, and deformed nucleoli. These results indicated that MCLR could induce toxic effects on the reproductive system of frogs, significantly decrease testosterone content, and rapidly increase estradiol content. Prolonged exposure and increased concentration enhanced the relative expression levels of P450 aromatase and steroidogenic factor 1; thus, endocrine function in frogs was disrupted. This study is the first to demonstrate in vivo MCLR toxicity in the reproductive system of male R. nigromaculata. This study provided a scientific basis of the global decline in amphibian populations.

  13. Stress-induced activation of the AMP-activated protein kinase in the freeze-tolerant frog Rana sylvatica.

    Science.gov (United States)

    Rider, Mark H; Hussain, Nusrat; Horman, Sandrine; Dilworth, Stephen M; Storey, Kenneth B

    2006-12-01

    Survival in the frozen state depends on biochemical adaptations that deal with multiple stresses on cells including long-term ischaemia and tissue dehydration. We investigated whether the AMP-activated protein kinase (AMPK) could play a regulatory role in the metabolic re-sculpting that occurs during freezing. AMPK activity and the phosphorylation state of translation factors were measured in liver and skeletal muscle of wood frogs (Rana sylvatica) subjected to anoxia, dehydration, freezing, and thawing after freezing. AMPK activity was increased 2-fold in livers of frozen frogs compared with the controls whereas in skeletal muscle, AMPK activity increased 2.5-, 4.5- and 3-fold in dehydrated, frozen and frozen/thawed animals, respectively. Immunoblotting with phospho-specific antibodies revealed an increase in the phosphorylation state of eukaryotic elongation factor-2 at the inactivating Thr56 site in livers from frozen frogs and in skeletal muscles of anoxic frogs. No change in phosphorylation state of eukaryotic initiation factor-2alpha at the inactivating Ser51 site was seen in the tissues under any of the stress conditions. Surprisingly, ribosomal protein S6 phosphorylation was increased 2-fold in livers from frozen frogs and 10-fold in skeletal muscle from frozen/thawed animals. However, no change in translation capacity was detected in cell-free translation assays with skeletal muscle extracts under any of the experimental conditions. The changes in phosphorylation state of translation factors are discussed in relation to the control of protein synthesis and stress-induced AMPK activation. PMID:16973146

  14. Features of the karyotypes of Pelophylax ridibundus Pallas, 1771 and Rana macrocnemis Boulenger, 1885 (Amphibia: Ranidae from Armenia

    Directory of Open Access Journals (Sweden)

    A Martirosyan

    2009-08-01

    Full Text Available Сhromosomal complements of Pelophylax ridibundus Pallas, 1771 from 9 localities (Northern, Central and South Armenia and Rana macrocnemis Boulenger, 1885 from one locality (North-West Armenia have been analyzed. The chromosome sets of P. ridibundus collected from 8 localities showed 2n=26, (10m+12sm+4st; NF=52. A secondary constriction has been observed in all studied individuals on the 10-th chromosome pair showing NOR-positive reaction. C-positive heterochromatin blocks have been observed on long arms of the 2-nd and 10-th pairs of chromosomes (7 localities. In addition, C-heterochromatin blocks have been found on interstitial regions of short arms of the 12-th pairs, as well as in telomeric regions of long arms of the 9-th pairs and on short arms of the 5-th pair in the frogs from 2 localities. The karyotype of P. ridibundus from populations near Ejmiatsin differs from other populations (2n=26, 12m+10sm+4st. Diploid number of chromosomes of R. macrocnemis was also 26 (8m+12sm+6st, NF=52. Blocks of C-positive heterochromatin have been revealed in telomeric parts of the 1-st, 2-nd (p, 3-rd (q, 4-th (q, 6-th, 9-th (p, 10-th (p,q and 13-th (q pairs, as well as in interstitial regions of the 1-st and 2-nd pairs of chromosomes.  Intrapopulation and interpopulation geographic variations of karyotypes and C-heterochromatin banding patterns of P. ridibundus have been revealed. Karyotypically, morphotypes “macrocnemis” and “camerani” are closely related.

  15. Histopathological changes and erythrocytic nuclear abnormalities in Iberian green frogs (Rana perezi Seoane) from a uranium mine pond

    International Nuclear Information System (INIS)

    In spite of their sensitivity to anthropogenic stressors, adults of Rana perezi Seoane were found inhabiting effluent ponds from a uranium mine. Due to the presence of such organisms in this environment, it becomes of paramount importance to assess the damages induced by local contamination on these aquatic vertebrates, in order to integrate this information on a site-specific risk assessment that is being carried out in the area. To attain this purpose an ethically and statistically acceptable number of green frogs were captured in the mine pond (M) and in a pristine river (VR), a few kilometres from the mine. Bioaccumulation of metals and histopathological alterations were evaluated in the liver, kidneys, spleen, lungs and testes of the animals. Simultaneously, blood samples were collected for the evaluation of genotoxic damage on erythrocytes. Animals captured in the M pond showed significantly increased levels of Be, Al, Mn, Fe and U in the liver, as well as Pb and U in the kidney. The liver was the main target organ for the bioaccumulation of Be, Al, Fe and U. However, renal histopathologies were more severe than those of liver. The main tissue alterations recorded in animals from the mine were: a slight increase in melanomacrophagic centers (MMC) in liver, lung and kidneys; dilatation of the renal tubules lumen associated with tubular necrosis. A significantly higher number of erythrocytic abnormalities (lobed, notched and kidney shaped nuclei and micronuclei) were recorded in frogs from M than in frogs from VR, along with a significantly lower frequency of immature erythrocytes. Both observations suggested that the removal of abnormal blood cells might be compromised

  16. Chilled frogs are hot: hibernation and reproduction of the Endangered mountain yellow-legged frog Rana muscosa

    Science.gov (United States)

    Santana, Frank E.; Swaisgood, Ronald R.; Lemm, Jeffrey M.; Fisher, Robert N.; Clark, Rulon W.

    2015-01-01

    In the face of the sixth great extinction crisis, it is imperative to establish effective breeding protocols for amphibian conservation breeding programs. Captive efforts should not proceed by trial and error, nor should they jump prematurely to assisted reproduction techniques, which can be invasive, difficult, costly, and, at times, counterproductive. Instead, conservation practitioners should first look to nature for guidance, and replicate key conditions found in nature in the captive environment, according to the ecological and behavioral requirements of the species. We tested the effect of a natural hibernation regime on reproductive behaviors and body condition in the Endangered mountain yellow-legged frog Rana muscosa. Hibernation had a clear positive effect on reproductive behavior, manifesting in vocal advertisement signaling, female receptivity, amplexus, and oviposition. These behaviors are critical components of courtship that lead to successful reproduction. Our main finding was that captive R. muscosa require a hibernation period for successful reproduction, as only hibernated females produced eggs and only hibernated males successfully fertilized eggs. Although hibernation also resulted in a reduced body condition, the reduction appeared to be minimal with no associated mortality. The importance of hibernation for reproduction is not surprising, since it is a major component of the conditions that R. muscosa experiences in the wild. Other amphibian conservation breeding programs can also benefit from a scientific approach that tests the effect of natural ecological conditions on reproduction. This will ensure that captive colonies maximize their role in providing genetic reservoirs for assurance and reintroduction efforts.

  17. Rana Dorada: un caminante hacia la extinción (artículo de opinión

    Directory of Open Access Journals (Sweden)

    Nury Natalia Garzón-Aguiar

    2015-07-01

    Full Text Available La extinción animal es un asunto muy amplio que a muchos interesa, algunos ignoran y otros desconocen, este es el tema a tratar en el presente artículo, tomando como ejemplo la rana dardo dorada (Phyllobates terribilis, un hermoso anfibio endémico de Colombia, denominado como el animal más venenoso y como una de las siete maravillas del mundo entre las especies amenazadas de extinción. Perteneciente al Reino ANIMALIA, al fillum de los Cordados, orden Anura y familia Dendrobatidae. En el Género Phyllobates se encuentra la especie P. terribilis, la cual, puede alcanzar un tamaño de hasta 47 mm en edad adulta y presentar distintas tonalidades de coloración. En Colombia, D. terribilis habita en la Costa Caribe así como en selvas húmedas, lugares con altos índices de explotación de los recursos naturales mediante la tala y la extracción minera, motivo por el cual está en vía de extinción. En este orden de ideas, el propósito principal es dar a conocer la importancia de atesorar los bosques y contribuir así a la conservación de las diversas especies, principalmente de la clase AMPHIBIA, y dentro de esta, el género Phyllobates, que puede representar una solución natural al control de plagas, así como probable remedio a un problema médico actual tan complejo como el dolor.

  18. Predation by Asian bullfrog tadpoles, Hoplobatrachus tigerinus, against the dengue vector, Aedes aegypti, in an aquatic environment treated with mosquitocidal nanoparticles.

    Science.gov (United States)

    Murugan, Kadarkarai; Priyanka, Vishwanathan; Dinesh, Devakumar; Madhiyazhagan, Pari; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Suresh, Udaiyan; Chandramohan, Balamurugan; Roni, Mathath; Nicoletti, Marcello; Alarfaj, Abdullah A; Higuchi, Akon; Munusamy, Murugan A; Khater, Hanem F; Messing, Russell H; Benelli, Giovanni

    2015-10-01

    Aedes aegypti is a primary vector of dengue and chikungunya. The use of synthetic insecticides to control Aedes populations often leads to high operational costs and adverse non-target effects. Botanical extracts have been proposed for rapid extracellular synthesis of mosquitocidal nanoparticles, but their impact against predators of mosquito larvae has not been well studied. We propose a single-step method for the biosynthesis of silver nanoparticles (AgNP) using the extract of Artemisia vulgaris leaves as a reducing and stabilizing agent. AgNP were characterized by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). SEM and XRD showed that AgNP were polydispersed, crystalline, irregularly shaped, with a mean size of 30-70 nm. EDX confirmed the presence of elemental silver. FTIR highlighted that the functional groups from plant metabolites capped AgNP, stabilizing them over time. We investigated the mosquitocidal properties of A. vulgaris leaf extract and green-synthesized AgNP against larvae and pupae of Ae. aegypti. We also evaluated the predatory efficiency of Asian bullfrog tadpoles, Hoplobatrachus tigerinus, against larvae of Ae. aegypti, under laboratory conditions and in an aquatic environment treated with ultra-low doses of AgNP. AgNP were highly toxic to Ae. aegypti larval instars (I-IV) and pupae, with LC50 ranging from 4.4 (I) to 13.1 ppm (pupae). In the lab, the mean number of prey consumed per tadpole per day was 29.0 (I), 26.0 (II), 21.4 (III), and 16.7 (IV). After treatment with AgNP, the mean number of mosquito prey per tadpole per day increased to 34.2 (I), 32.4 (II), 27.4 (III), and 22.6 (IV). Overall, this study highlights the importance of a synergistic approach based on biocontrol agents and botanical nano-insecticides for mosquito control. PMID:26091763

  19. Assessment of thyroid system disruption in Rana pipiens tadpoles chronically exposed to UVB radiation and 4-tert-octylphenol

    International Nuclear Information System (INIS)

    Many studies have considered recent increases in ultraviolet B radiation (UVBR) and endocrine disrupting chemicals polluting the environment as possible contributing factors to the reduction in amphibian populations. It has been demonstrated that exposure of amphibians to estrogenic chemicals or UVBR can affect the timing of larval development and metamorphosis. However, amphibians in the wild are exposed to multiple environmental stressors simultaneously. Therefore, our study examines the effects of UVBR and the estrogenic chemical 4-tert-octylphenol (OP), alone and in combination, on the thyroid system of Rana pipiens tadpoles, which is the main regulator of amphibian metamorphosis. Results demonstrate that thyroid gland histomorphology measurements in Gosner stage 31 tadpoles continuously exposed to UVBR (0.21 W/m2) were not different than those measured in animals from the control group. In a separate experiment, tadpoles exposed to environmentally relevant levels of UVBR (0.22 W/m2) and/or OP (0.01 nM or 10 nM) exhibited significantly delayed development starting from Gosner stage 29, given that fewer tadpoles developed past stage 29 in these groups. In addition, significantly fewer UVBR-treated tadpoles developed past stage 34 and metamorphosed. Samples were collected from stages 29 and 34 tadpoles for gene expression analysis in tail tissue and measurements of T3 (triiodothyronine) whole body levels (minus tail). UVBR and/or OP exposure did not affect T3 levels in stages 29 and 34 tadpoles. However, a decrease in deiodinase type 2 (D2) or increase in deiodinase type 3 (D3) mRNA levels was observed in groups of tadpoles with slowed developmental rates at those developmental stages. Given that D2 activates and D3 inactivates thyroid hormones (TH), UVBR/OP mediated disruptions in development are likely caused by dysfunctions in the localized metabolism of THs through alterations in the expression of these enzymes in peripheral tissues. This is the first study

  20. Assessment of thyroid system disruption in Rana pipiens tadpoles chronically exposed to UVB radiation and 4-tert-octylphenol

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, M.C., E-mail: maxinecroteau@hotmail.com [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada); Davidson, M., E-mail: mdavi089@uottawa.ca [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada); Duarte-Guterman, P., E-mail: duarte.paula@gmail.com [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada); Wade, M., E-mail: mike_wade@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Columbine Driveway, Tunney' s Pasture, Ottawa, Ontario, K1A 0K9 (Canada); Popesku, J.T., E-mail: jpopesku@gmail.com [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada); Wiens, S., E-mail: susannawiens@hotmail.com [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada); Lean, D.R.S., E-mail: dlean@uottawa.ca [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada); Trudeau, V.L., E-mail: trudeauv@uottawa.ca [Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, 20 Marie Curie Street, Ottawa, Ontario, K1N 6N5 (Canada)

    2009-11-08

    Many studies have considered recent increases in ultraviolet B radiation (UVBR) and endocrine disrupting chemicals polluting the environment as possible contributing factors to the reduction in amphibian populations. It has been demonstrated that exposure of amphibians to estrogenic chemicals or UVBR can affect the timing of larval development and metamorphosis. However, amphibians in the wild are exposed to multiple environmental stressors simultaneously. Therefore, our study examines the effects of UVBR and the estrogenic chemical 4-tert-octylphenol (OP), alone and in combination, on the thyroid system of Rana pipiens tadpoles, which is the main regulator of amphibian metamorphosis. Results demonstrate that thyroid gland histomorphology measurements in Gosner stage 31 tadpoles continuously exposed to UVBR (0.21 W/m{sup 2}) were not different than those measured in animals from the control group. In a separate experiment, tadpoles exposed to environmentally relevant levels of UVBR (0.22 W/m{sup 2}) and/or OP (0.01 nM or 10 nM) exhibited significantly delayed development starting from Gosner stage 29, given that fewer tadpoles developed past stage 29 in these groups. In addition, significantly fewer UVBR-treated tadpoles developed past stage 34 and metamorphosed. Samples were collected from stages 29 and 34 tadpoles for gene expression analysis in tail tissue and measurements of T3 (triiodothyronine) whole body levels (minus tail). UVBR and/or OP exposure did not affect T3 levels in stages 29 and 34 tadpoles. However, a decrease in deiodinase type 2 (D2) or increase in deiodinase type 3 (D3) mRNA levels was observed in groups of tadpoles with slowed developmental rates at those developmental stages. Given that D2 activates and D3 inactivates thyroid hormones (TH), UVBR/OP mediated disruptions in development are likely caused by dysfunctions in the localized metabolism of THs through alterations in the expression of these enzymes in peripheral tissues. This is the

  1. Foraging behaviour in tadpoles of the bronze frog Rana temporalis: Experimental evidence for the ideal free distribution

    Indian Academy of Sciences (India)

    Dheeraj K Veeranagoudar; Bhagyashri A Shanbhag; Srinivas K Saidapur

    2004-06-01

    The ability of bronze frog Rana temporalis tadpoles (pure or mixed parental lines) to assess the profitability of food habitats and distribute themselves accordingly was tested experimentally using a rectangular choice tank with a non-continuous input design. Food (boiled spinach) was placed at two opposite ends of the choice tank in a desired ratio (1 : 1, 1 : 2 or 1 : 4) to create habitat A and B. The tadpoles in Gosner stage 28–33, pre-starved for 24 h, were introduced in an open ended mesh cylinder placed in the center of the choice tank, held for 4 min (for acclimation) and then released to allow free movement and habitat selection. The number of tadpoles foraging at each habitat was recorded at 10, 15, 20, 25 and 30 min time intervals. The actual suitability, (the food available in a habitat after colonization of tadpoles) of each habitat was obtained from the equation = - () where is basic suitability (amount of food provided at each habitat before release of tadpoles), is the rate of depletion of food (lowering effect) with introduction of each tadpole, and is the density of tadpoles in habitat . The expected number of tadpoles at each habitat was derived from the actual suitability. With no food in the choice tank, movement of the tadpoles in the test arena was random indicating no bias towards any end of the choice tank or the procedure. In tests with a 1 : 1 food ratio, the observed ratio of tadpoles (11.71 : 12.28) was comparable with the expected 12 : 12 ratio. The observed number of tadpoles in the habitats with a 1 : 2 food ratio was 8.71 : 15.29 and 7.87 : 16.13 for pure and mixed parental lines respectively. In both cases, the observed ratios were close to the expected values (7 : 17). Likewise, in experiments with a 1 : 4 food ratio, the observed number of tadpoles in the two habitats (10.78 : 37.22) did not differ significantly from the expected ratio of 7 : 41. In all tests, the number of R. temporalis tadpoles matched ideally with

  2. Alteration of the hypothalamic-pituitary-gonadal axis in estrogen- and androgen-treated adult male leopard frog, Rana pipiens

    Directory of Open Access Journals (Sweden)

    Jones Jeremy T

    2005-01-01

    Full Text Available Abstract Background Gonadal steroids, in particular 5 alpha-dihydrotestosterone (DHT and 17 beta-estradiol (E2, have been shown to feed back on the hypothalamic-pituitary-gonadal (HPG axis of the ranid frog. However, questions still remain on how DHT and E2 impact two of the less-studied components of the ranid HPG axis, the hypothalamus and the gonad, and if the feedback effects are consistently negative. Thus, the goal of the study was to examine the effects of DHT and E2 upon the HPG axis of the gonadally-intact, sexually mature male leopard frogs, Rana pipiens. Methods R. pipiens were implanted with silastic capsules containing either cholesterol (Ch, a control, DHT, or E2 for 10 or 30 days. At each time point, steroid-induced changes in hypothalamic GnRH and pituitary LH concentrations, circulating luteinizing hormone (LH, and testicular histology were examined. Results Frogs implanted with DHT or E2 for 10 days did not show significant alterations in the HPG axis. In contrast, frogs implanted with hormones for 30 days had significantly lower circulating LH (for both DHT and E2, decreased pituitary LH concentration (for E2 only, and disrupted spermatogenesis (for both DHT and E2. The disruption of spermatogenesis was qualitatively similar between DHT and E2, although the effects of E2 were consistently more potent. In both DHT and E2-treated animals, a marked loss of all pre-meiotic germ cells was observed, although the loss of secondary spermatogonia appeared to be the primary cause of disrupted spermatogenesis. Unexpectedly, the presence of post-meiotic germ cells was either unaffected or enhanced by DHT or E2 treatment. Conclusions Overall, these results showed that both DHT and E2 inhibited circulating LH and disrupted spermatogenesis progressively in a time-dependent manner, with the longer duration of treatment producing the more pronounced effects. Further, the feedback effects exerted by both steroid hormones upon the HPG axis were

  3. A de novo Assembly of the Common Frog (Rana temporaria Transcriptome and Comparison of Transcription Following Exposure to Ranavirus and Batrachochytrium dendrobatidis.

    Directory of Open Access Journals (Sweden)

    Stephen J Price

    Full Text Available Amphibians are experiencing global declines and extinctions, with infectious diseases representing a major factor. In this study we examined the transcriptional response of metamorphic hosts (common frog, Rana temporaria to the two most important amphibian pathogens: Batrachochytrium dendrobatidis (Bd and Ranavirus. We found strong up-regulation of a gene involved in the adaptive immune response (AP4S1 at four days post-exposure to both pathogens. We detected a significant transcriptional response to Bd, covering the immune response (innate and adaptive immunity, complement activation, and general inflammatory responses, but relatively little transcriptional response to Ranavirus. This may reflect the higher mortality rates found in wild common frogs infected with Ranavirus as opposed to Bd. These data provide a valuable genomic resource for the amphibians, contribute insight into gene expression changes after pathogen exposure, and suggest potential candidate genes for future host-pathogen research.

  4. Response of the Italian agile frog (Rana latastei) to a Ranavirus, frog virus 3: a model for viral emergence in naïve populations.

    Science.gov (United States)

    Pearman, Peter B; Garner, Trenton W J; Straub, Monika; Greber, Urs F

    2004-10-01

    Ranavirus (family Iridoviridae) is a genus of pathogens of poikilotherms, and some ranaviruses may play a role in widespread mortality of amphibians. Ecology of viral transmission in amphibians is poorly known but can be addressed through experimentation in the laboratory. In this study, we use the Ranavirus frog virus 3 (FV3) as an experimental model for pathogen emergence in naive populations of tadpoles. We simulated emerging disease by exposing tadpoles of the Italian agile frog (Rana latastei), to the North American Ranavirus FV3. We demonstrated that mortality occurred due to viral exposure, exposure of tadpoles to decreasing concentrations of FV3 in the laboratory produced dose-dependent survival rates, and cannibalism of virus-carrying carcasses increased mortality due to FV3. These experiments suggest the potential for ecological mechanisms to affect the level of exposure of tadpoles to Ranavirus and to impact transmission of viral pathogens in aquatic systems. PMID:15650083

  5. Una nueva especie de rana terrestre del género Pristimantis (Amphibia: Craugastoridae, de la Cordillera de Kutukú, Ecuador

    Directory of Open Access Journals (Sweden)

    Jorge Brito M.

    2013-01-01

    Full Text Available Describimos una especie nueva de mediano tamaño (LRC en la hembra 38.7 mm; en machos de 23.8 a 26.4 mm de rana terrestre del género Pristimantis de los bosques sub-tropicales de la Cordillera de Kutukú, del sureste de Ecuador, a elevaciones de 1581-1820 m. Asignamos a Pristimantis almendariz sp. nov., al subgénero Hypodictyon, serie de especies ridens. La nueva especie difiere de otros miembros de la serie ridens por su patrón distintivo con manchas dorsales, membrana timpánica ausente, presencia de tubérculos cónicos agrandados en el párpado, tubérculo inter-orbital prominente, e iris plateado con reticulaciones negras.

  6. 林蛙皮胶原蛋白的提取及抗氧化性%Extraction of Rana Chensinensis Skin Collagen by Papain and its Antioxidant Activity

    Institute of Scientific and Technical Information of China (English)

    吕玲玲; 金香淑; 施溯筠

    2013-01-01

      用木瓜蛋白酶提取林蛙皮胶原蛋白,采用单因素试验和正交试验设计优选最佳提取工艺,并对林蛙皮胶原蛋白的抗氧化性进行研究。结果表明:林蛙皮胶原蛋白的最佳提取工艺是加酶量为1%,料液比为1∶20(g/mL),pH为5.5于室温反应36 h,此条件下胶原蛋白提取率为24.71%,纯度为72.03%。林蛙皮胶原蛋白具有一定的还原能力,对羟自由基具有一定的清除能力,并且随着浓度的增加抗氧化活性逐渐增强。%  Extraction of Rana Chensinensis skin collagen by papain and its antioxidant activity were studied in this paper. The results of the single factor experiment and orthogonal test were as follows: the hydrolysis temperature of room temperature, reaction time of 36 h, pH of 5.5, enzyme concentration of 1%and the ratio of solid to liquid 1∶20 (g/mL). Its recovery yield was 24.71%and the degree of puirty was 72.03%. Collagen of Rana Chensinensis Skin had strong reducing capacity and antioxidant activity on scavenging hydroxyl free radical effects .

  7. Extraction of Rana Chensinensis Skin Collagen by Papain and its Antioxidant Activity%林蛙皮胶原蛋白的提取及抗氧化性

    Institute of Scientific and Technical Information of China (English)

    吕玲玲; 金香淑; 施溯筠

    2013-01-01

      Extraction of Rana Chensinensis skin collagen by papain and its antioxidant activity were studied in this paper. The results of the single factor experiment and orthogonal test were as follows: the hydrolysis temperature of room temperature, reaction time of 36 h, pH of 5.5, enzyme concentration of 1%and the ratio of solid to liquid 1∶20 (g/mL). Its recovery yield was 24.71%and the degree of puirty was 72.03%. Collagen of Rana Chensinensis Skin had strong reducing capacity and antioxidant activity on scavenging hydroxyl free radical effects .%  用木瓜蛋白酶提取林蛙皮胶原蛋白,采用单因素试验和正交试验设计优选最佳提取工艺,并对林蛙皮胶原蛋白的抗氧化性进行研究。结果表明:林蛙皮胶原蛋白的最佳提取工艺是加酶量为1%,料液比为1∶20(g/mL),pH为5.5于室温反应36 h,此条件下胶原蛋白提取率为24.71%,纯度为72.03%。林蛙皮胶原蛋白具有一定的还原能力,对羟自由基具有一定的清除能力,并且随着浓度的增加抗氧化活性逐渐增强。

  8. Larval Environment Alters Amphibian Immune Defenses Differentially across Life Stages and Populations.

    Directory of Open Access Journals (Sweden)

    Katherine L Krynak

    Full Text Available Recent global declines, extirpations and extinctions of wildlife caused by newly emergent diseases highlight the need to improve our knowledge of common environmental factors that affect the strength of immune defense traits. To achieve this goal, we examined the influence of acidification and shading of the larval environment on amphibian skin-associated innate immune defense traits, pre and post-metamorphosis, across two populations of American Bullfrogs (Rana catesbeiana, a species known for its wide-ranging environmental tolerance and introduced global distribution. We assessed treatment effects on 1 skin-associated microbial communities and 2 post-metamorphic antimicrobial peptide (AMP production and 3 AMP bioactivity against the fungal pathogen Batrachochytrium dendrobatidis (Bd. While habitat acidification did not affect survival, time to metamorphosis or juvenile mass, we found that a change in average pH from 7 to 6 caused a significant shift in the larval skin microbial community, an effect which disappeared after metamorphosis. Additionally, we found shifts in skin-associated microbial communities across life stages suggesting they are affected by the physiological or ecological changes associated with amphibian metamorphosis. Moreover, we found that post-metamorphic AMP production and bioactivity were significantly affected by the interactions between pH and shade treatments and interactive effects differed across populations. In contrast, there were no significant interactions between treatments on post-metamorphic microbial community structure suggesting that variation in AMPs did not affect microbial community structure within our study. Our findings indicate that commonly encountered variation in the larval environment (i.e. pond pH and degree of shading can have both immediate and long-term effects on the amphibian innate immune defense traits. Our work suggests that the susceptibility of amphibians to emerging diseases could be

  9. Integrating Individual-Based Indices of Contaminant Effects

    Directory of Open Access Journals (Sweden)

    Christopher L. Rowe

    2001-01-01

    Full Text Available Habitat contamination can alter numerous biological processes in individual organisms. Examining multiple individual-level responses in an integrative fashion is necessary to understand how individual health or fitness reflects environmental contamination. Here we provide an example of such an integrated perspective based upon recent studies of an amphibian (the bullfrog, Rana catesbeiana that experiences several, disparate changes when larval development occurs in a trace element�contaminated habitat. First, we present an overview of studies focused on specific responses of individuals collected from, or transplanted into, a habitat contaminated by coal combustion residues (CCR. These studies have reported morphological, behavioral, and physiological modifications to individuals chronically interacting with sediments in the CCR-contaminated site. Morphological abnormalities in the oral and tail regions in contaminant-exposed individuals influenced other properties such as grazing, growth, and swimming performance. Behavioral changes in swimming activities and responses to stimuli appear to influence predation risk in the contaminant-exposed population. Significant changes in bioenergetics in the contaminated habitat, evident as abnormally high energetic expenditures for survival (maintenance costs, may ultimately influence production pathways (growth, energy storage in individuals. We then present a conceptual model to examine how interactions among the affected systems (morphological, behavioral, physiological may ultimately bring about more severe effects than would be predicted if the responses were considered in isolation. A complex interplay among simultaneously occurring biological changes emerges in which multiple, sublethal effects ultimately can translate into reductions in larval or juvenile survival, and thus reduced recruitment of juveniles into the population. In systems where individuals are exposed to low concentrations of

  10. The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development

    International Nuclear Information System (INIS)

    We investigated whether exposure to environmentally relevant concentrations of the bactericidal agent, triclosan, induces changes in the thyroid hormone-mediated process of metamorphosis of the North American bullfrog, Rana catesbeiana and alters the expression profile of thyroid hormone receptor (TR) α and β, basic transcription element binding protein (BTEB) and proliferating nuclear cell antigen (PCNA) gene transcripts. Premetamorphic tadpoles were immersed in environmentally relevant concentrations of triclosan and injected with 1 x 10-11 mol/g body weight 3,5,3'-triiodothyronine (T3) or vehicle control. Morphometric measurements and steady-state mRNA levels obtained by quantitative polymerase chain reaction were determined. mRNA abundance was also examined in Xenopus laevis XTC-2 cells treated with triclosan and/or 10 nM T3. Tadpoles pretreated with triclosan concentrations as low as 0.15 ± 0.03 μg/L for 4 days showed increased hindlimb development and a decrease in total body weight following T3 administration. Triclosan exposure also resulted in decreased T3-mediated TRβ mRNA expression in the tadpole tail fin and increased levels of PCNA transcript in the brain within 48 h of T3 treatment whereas TRα and BTEB were unaffected. Triclosan alone altered thyroid hormone receptor α transcript levels in the brain of premetamorphic tadpoles and induced a transient weight loss. In XTC-2 cells, exposure to T3 plus nominal concentrations of triclosan as low as 0.03 μg/L for 24 h resulted in altered thyroid hormone receptor mRNA expression. Exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development

  11. The bactericidal agent triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development

    Energy Technology Data Exchange (ETDEWEB)

    Veldhoen, Nik [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Skirrow, Rachel C. [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Osachoff, Heather [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Wigmore, Heidi [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Clapson, David J. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Gunderson, Mark P. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada); Van Aggelen, Graham [Pacific Environmental Science Centre, 2645 Dollarton Highway, North Vancouver, British Columbia V7H 1V2 (Canada); Helbing, Caren C. [Department of Biochemistry and Microbiology, P.O. Box 3055, Stn. CSC, University of Victoria, Victoria, British Columbia V8W 3P6 (Canada)]. E-mail: chelbing@uvic.ca

    2006-12-01

    We investigated whether exposure to environmentally relevant concentrations of the bactericidal agent, triclosan, induces changes in the thyroid hormone-mediated process of metamorphosis of the North American bullfrog, Rana catesbeiana and alters the expression profile of thyroid hormone receptor (TR) {alpha} and {beta}, basic transcription element binding protein (BTEB) and proliferating nuclear cell antigen (PCNA) gene transcripts. Premetamorphic tadpoles were immersed in environmentally relevant concentrations of triclosan and injected with 1 x 10{sup -11} mol/g body weight 3,5,3'-triiodothyronine (T{sub 3}) or vehicle control. Morphometric measurements and steady-state mRNA levels obtained by quantitative polymerase chain reaction were determined. mRNA abundance was also examined in Xenopus laevis XTC-2 cells treated with triclosan and/or 10 nM T{sub 3}. Tadpoles pretreated with triclosan concentrations as low as 0.15 {+-} 0.03 {mu}g/L for 4 days showed increased hindlimb development and a decrease in total body weight following T{sub 3} administration. Triclosan exposure also resulted in decreased T{sub 3}-mediated TR{beta} mRNA expression in the tadpole tail fin and increased levels of PCNA transcript in the brain within 48 h of T{sub 3} treatment whereas TR{alpha} and BTEB were unaffected. Triclosan alone altered thyroid hormone receptor {alpha} transcript levels in the brain of premetamorphic tadpoles and induced a transient weight loss. In XTC-2 cells, exposure to T{sub 3} plus nominal concentrations of triclosan as low as 0.03 {mu}g/L for 24 h resulted in altered thyroid hormone receptor mRNA expression. Exposure to low levels of triclosan disrupts thyroid hormone-associated gene expression and can alter the rate of thyroid hormone-mediated postembryonic anuran development.

  12. Slow dynamics of the amphibian tympanic membrane

    Science.gov (United States)

    Bergevin, Christopher; Meenderink, Sebastiaan W. F.; van der Heijden, Marcel; Narins, Peter M.

    2015-12-01

    Several studies have demonstrated that delays associated with evoked otoacoustic emissions (OAEs) largely originate from filter delays of resonant elements in the inner ear. However, one vertebrate group is an exception: Anuran (frogs and toads) amphibian OAEs exhibit relatively long delays (several milliseconds), yet relatively broad tuning. These delays, also apparent in auditory nerve fiber (ANF) responses, have been partially attributed to the middle ear (ME), with a total forward delay of ˜0.7 ms (˜30 times longer than in gerbil). However, ME forward delays only partially account for the longer delays of OAEs and ANF responses. We used scanning laser Doppler vibrometery to map surface velocity over the tympanic membrane (TyM) of anesthetized bullfrogs (Rana catesbeiana). Our main finding is a circularly-symmetric wave on the TyM surface, starting at the outer edges of the TyM and propagating inward towards the center (the site of the ossicular attachment). This wave exists for frequencies ˜0.75-3 kHz, overlapping the range of bullfrog hearing (˜0.05-1.7 kHz). Group delays associated with this wave varied from 0.4 to 1.2 ms and correlated with with TyM diameter, which ranged from ˜6-16 mm. These delays correspond well to those from previous ME measurements. Presumably the TyM waves stem from biomechanical constraints of semi-aquatic species with a relatively large tympanum. We investigated some of these constraints by measuring the pressure ratio across the TyM (˜10-30 dB drop, delay of ˜0.35 ms), the effects of ossicular interruption, the changes due to physiological state of TyM (`dry-out'), and by calculating the middle-ear input impedance. In summary, we found a slow, inward-traveling wave on the TyM surface that accounts for a substantial fraction of the relatively long otoacoustic and neurophysiological delays previously observed in the anuran inner ear.

  13. Exposure to coal combustion residues during metamorphosis elevates corticosterone content and adversely affects oral morphology, growth, and development in Rana sphenocephala

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, J.D.; Peterson, V.A.; Mendonca, M.T. [Auburn University, Auburn, AL (USA). Dept. of Biological Science

    2009-01-15

    Coal combustion residues (CCRs) are documented to negatively impact oral morphology, growth, and development in larval amphibians. It is currently unclear what physiological mechanisms may mediate these effects. Corticosterone, a glucocorticoid hormone, is a likely mediator because when administered exogenously it, like CCRs, also negatively influences oral morphology, growth, and development in larval amphibians. In an attempt to identify if corticosterone mediates these effects, we raised larval Southern Leopard Frogs, Rana sphenocephala, on either sand or CCR substrate and documented effects of sediment type on whole body corticosterone, oral morphology, and time to and mass at key metamorphic stages. Coal combustion residue treated tadpoles contained significantly more corticosterone than controls throughout metamorphosis. However, significantly more oral abnormalities occurred early in metamorphosis when differences in corticosterone levels between treatments were minimal. Overall, CCR-treated tadpoles took significantly more time to transition between key stages and gained less mass between stages than controls, but these differences between treatments decreased during later stages when corticosterone differences between treatments were greatest. Our results suggest endogenous increase in corticosterone content and its influence on oral morphology, growth and development is more complex than previously thought.

  14. Hepatocyte responses to in vitro freezing and β-adrenergic stimulation: Insights into the extreme freeze tolerance of subarctic Rana sylvatica.

    Science.gov (United States)

    do Amaral, M Clara F; Lee, Richard E; Costanzo, Jon P

    2015-02-01

    The wood frog, Rana sylvatica LeConte 1825, is a freeze-tolerant amphibian widely distributed in North America. Subarctic populations of this species can survive experimental freezing to temperatures below -16 °C, whereas temperate populations tolerate freezing only at temperatures above -6 °C. We investigated whether hepatocytes isolated from frogs indigenous to Interior Alaska (subarctic) or southern Ohio (temperate) had distinct characteristics that could contribute to this variation in freeze tolerance capacity. Following in vitro freezing, cell damage, as assessed from lactate dehydrogenase leakage, was similar between samples from Alaskan and Ohioan frogs. Preincubation of cells in media containing glucose or urea, the two primary cryoprotectants used by R. sylvatica, markedly reduced freezing damage to hepatocytes; however, results suggested that cells of the northern phenotype were comparatively more amenable to cryoprotection by urea. Stimulation of isolated hepatocytes with β-adrenergic agonists, which simulates the freezing-induced cryoprotectant mobilization response, gave rates of glucose production from endogenous glycogen reserves that were similar between the populations. Our findings suggest that extreme freeze tolerance in subarctic R. sylvatica does not require an enhanced ability of the liver to resist freezing stress or rapidly mobilize cryoprotectant. PMID:25581737

  15. Comparison of diet, reproductive biology, and growth of the pig frog (Rana grylio) from harvested and protected areas of the Florida Everglades

    Science.gov (United States)

    Ugarte, C.A.; Rice, K.G.; Donnelly, M.A.

    2007-01-01

    Distinct differences in body size exist among three Rana grylio populations in areas of the Florida Everglades that differ in frog harvest pressure and hydroperiod. Frogs from two populations are harvested regularly throughout the year, while those in the third are protected from harvest. We compared seasonal and sex differences in diet, reproduction, and growth across these populations to examine life-history patterns. By volume, crayfish and anurans were the most abundant prey items for all adults across sites. Frogs from drier sites consumed more crayfish than frogs from the wettest site. Anurans were abundant in the diet during the wet season, while crayfish and fish were abundant during the dry season. More frogs with empty stomachs were captured during the wet season than the dry season. Feeding, growth, and fat deposition were greatest during the dry season across all sites. Although females were found in all reproductive stages throughout the year, the highest percentage of females had mature ova during the late dry season and spent ovaries during the early wet season. Individual patterns of growth were similar across all sites and matched historical growth data from the 1950s. Differences in body size among sites were most likely attributable to differential mortality (i.e., harvest pressure, predation) rather than to differences in food access or growth. ?? 2007 by the American Society of Ichthyologists and Herpetologists.

  16. Synergistic inhibition of the lethal fungal pathogen Batrachochytrium dendrobatidis: the combined effect of symbiotic bacterial metabolites and antimicrobial peptides of the frog Rana muscosa.

    Science.gov (United States)

    Myers, Jillian M; Ramsey, Jeremy P; Blackman, Alison L; Nichols, A Elizabeth; Minbiole, Kevin P C; Harris, Reid N

    2012-08-01

    A powerful mechanism for protection against disease in animals is synergy between metabolites present in the natural microbiota of the host and antimicrobial peptides (AMPs) produced by the host. We studied this method of protection in amphibians in regard to the lethal disease chytridiomycosis, which is caused by Batrachochytrium dendrobatidis (Bd). In this study, we show that the AMPs of Rana muscosa, as well as the metabolite 2,4-diacetylphloroglucinol (2,4-DAPG) from Pseudomonas fluorescens, a bacterial species normally found on the skin of R. muscosa, were inhibitory to the growth of Bd in vitro. When both AMPs and 2,4-DAPG were used in growth inhibition assays, they worked synergistically to inhibit the growth of Bd. This synergy resulted in reduced minimum concentrations necessary for inhibition by either 2,4-DAPG or AMPs. This inhibitory concentration of AMPs did not inhibit the growth of a P. fluorescens strain that produced 2,4-DAPG in vitro, although its growth was inhibited at higher peptide concentrations. These data suggest that the AMPs secreted onto frog skin and the metabolites secreted by the resident beneficial bacteria may work synergistically to enhance protection against Bd infection on amphibian skin. These results may aid conservation efforts to augment amphibian skins' resistance to chytridiomycosis by introducing anti-Bd bacterial species that work synergistically with amphibian AMPs. PMID:22914957

  17. Heavy metal accumulation and metallothionein concentration in the frog Rana ridibunda after exposure to chromium or a mixture of chromium and cadmium

    International Nuclear Information System (INIS)

    The accumulation of two heavy metals (chromium (Cr) and cadmium (Cd)) in the liver, kidney and gut of Rana ridibunda exposed to Cr or to a mixture of Cr and Cd was investigated. The concentration of metallothioneins (MTs) in the same tissues was also studied. Both metals accumulated mainly in the kidney. Cr accumulation in the liver and gut was not affected by the presence of Cd. Furthermore, Cr concentration in the kidney was doubled when Cd was present. MT concentration did not increase after Cr treatment but it increased two- to six-fold over control values in mixture-exposed frogs, the highest value being observed in the gut. MTs in the gut could act as a barrier preventing ingested heavy metals from entering the blood stream. MT concentration correlated positively with Cd concentrations in both the liver and the gut of mixture-exposed animals. - Exposure to Cr and a mixture of Cd and Cr resulted in increased concentrations of MTs only in mixture-exposed frogs

  18. Density-dependent growth and metamorphosis in the larval bronze frog Rana temporalis is influenced by genetic relatedness of the cohort

    Indian Academy of Sciences (India)

    S Girish; S K Saidapur

    2003-06-01

    Effects of density and kinship on growth and metamorphosis in tadpoles of Rana temporalis were studied in a 2 × 4 factorial experiment. Fifteen egg masses were collected from streams in the Western Ghat region of south India. The tadpoles were raised as siblings or in groups of non-siblings at increasing density levels, viz. 15, 30, 60 and 120/5 l water. With an increase in density level from 15 to 120 tadpoles/5 l water, duration of the larval stage increased and fewer individuals metamorphosed irrespective of whether they belonged to sibling or non-sibling groups by day 100 when the experiments were terminated. The size of individuals at metamorphosis declined significantly with increase in the density of rearing. However, at higher densities (60 and 120 tadpoles/5 l water) sibling group tadpoles performed better compared to mixed groups and took significantly less time to metamorphose. Also, more individuals of sibling groups metamorphosed compared to non-sibling groups at a given density. Mixed rearing retarded growth rates, prolonged larval duration resulting in a wider spectrum of size classes, and lowered the number of individuals recruited to terrestrial life. The study shows that interference competition occurred more strongly in cohorts of mixed relatedness than in sibling groups.

  19. Characterization of the Rana grylio virus 3β-hydroxysteroid dehydrogenase and its novel role in suppressing virus-induced cytopathic effect

    International Nuclear Information System (INIS)

    The 3β-hydroxysteroid dehydrogenase (3β-HSD) isoenzymes play a key role in cellular steroid hormone synthesis. Here, a 3β-HSD gene homolog was cloned from Rana grylio virus (RGV), a member of family Iridoviridae. RGV 3β-HSD gene has 1068 bp, encoding a 355 aa predicted protein. Transcription analyses showed that RGV 3β-HSD gene was transcribed immediate-early during infection from an initiation site 19 nucleotides upstream of the translation start site. Confocal microscopy revealed that the 3β-HSD-EGFP fusion protein was exclusively colocalized with the mitochondria marker (pDsRed2-Mito) in EPC cells. Upon morphological observation and MTT assay, it was revealed that overexpression of RGV 3β-HSD in EPC cells could apparently suppress RGV-induced cytopathic effect (CPE). The present studies indicate that the RGV immediate-early 3β-HSD gene encodes a mitochondria-localized protein, which has a novel role in suppressing virus-induced CPE. All these suggest that RGV 3β-HSD might be a protein involved in host-virus interaction

  20. Nueva especie de rana terrestre del género Pristimantis (Amphibia: Craugastoridae, meseta de la Dordillera del Cóndor

    Directory of Open Access Journals (Sweden)

    Jorge Brito M.

    2014-01-01

    Full Text Available Describimos una especie nueva, de mediano tamaño (LRC en la hembra 21.7-24.9 mm; en machos 15.2-17.8 mm, de rana terrestre del género Pristimantis proveniente de la meseta de arenisca de la Cordillera del Cóndor, del sureste de Ecuador, con una elevacion de 2300 m. La nueva especie difiere de sus congéneres presentes en Ecuador por su patrón distintivo de coloración, superficie dorsal pardo ocráceo con numerosas manchas amarillentas, membrana timpánica presente, dedos pediales y manuales cortos y microhábitat exclusivo en bromelias terrestres. Las llamadas son largas, de frecuencia modulada, conformada por 6-8 notas y un armónico. La descripción de Pristimantis paquishae sp. nov., es el resultado de un levantamiento de información de la herpetofauna, en una de las mesetas de arenisca remotas y menos conocidas, en la Cordillera del Cóndor.

  1. Functional studies of a glucagon receptor isolated from frog Rana tigrina rugulosa: implications on the molecular evolution of glucagon receptors in vertebrates.

    Science.gov (United States)

    Ngan, E S; Chow, L S; Tse, D L; Du, X; Wei, Y; Mojsov, S; Chow, B K

    1999-09-01

    In this report, the first amphibian glucagon receptor (GluR) cDNA was characterized from the liver of the frog Rana tigrina rugulosa. Functional expression of the frog GluR in CHO and COS-7 cells showed a high specificity of the receptor towards human glucagon with an EC(50) value of 0.8+/-0.5 nM. The binding of radioiodinated human glucagon to GluR was displaced in a dose-dependent manner only with human glucagon and its antagonist (des-His(1)-[Nle(9)-Ala(11)-Ala(16)]) with IC(50) values of 12.0+/-3. 0 and 7.8+/-1.0 nM, respectively. The frog GluR did not display any affinity towards fish and human GLP-1s, and towards glucagon peptides derived from two species of teleost fishes (goldfish, zebrafish). These fish glucagons contain substitutions in several key residues that were previously shown to be critical for the binding of human glucagon to its receptor. By RT-PCR, mRNA transcripts of frog GluR were located in the liver, brain, small intestine and colon. These results demonstrate a conservation of the functional characteristics of the GluRs in frog and mammalian species and provide a framework for a better understanding of the molecular evolution of the GluR and its physiological function in vertebrates. PMID:10471837

  2. Purification and Enzyme Analysis of A Virus from Frog ( Rana tigrina rugulosa)%一种蛙病毒的纯化和酶切分析

    Institute of Scientific and Technical Information of China (English)

    吕玲; 何建国; 何华虹; 邓敏; 王晓红; 翁少萍

    2001-01-01

    从患病虎纹蛙(%Rana tigrina rugulosa)%蝌蚪中分离得到一种蛙病毒,感染鱼的FHM 、CO、EPC细胞,获得大量的病毒原料,分离纯化得到高纯度的病毒粒子,电镜下可见病毒粒子为二十面体,具囊膜,直径平均为125 nm.抽提病毒核酸,对其基因组DNA进行酶切分析,病毒基因组为双链DNA分子,表现脊椎动物虹彩病毒基因组的特点即其胞嘧啶5′端高度甲基化.以限制性内切酶%XbaⅠ、Bam%H%Ⅰ、Hin%d%Ⅲ、KpnⅠ和PstⅠ酶切病毒基因组%DNA,经电泳分离后,分别得到13、25、6、14、22条清晰的酶切片段,并根据酶切片段算得基因组的大小超过100 kb.用PCR方法,得到这个病毒的主衣壳蛋白(MCP)基因保守序列,与FV3相比,同源性达98%.

  3. Identification of a proglucagon cDNA from Rana tigrina rugulosa that encodes two GLP-1s and that is alternatively spliced in a tissue-specific manner.

    Science.gov (United States)

    Yeung, C M; Chow, B K

    2001-11-01

    Glucagon plays a pivotal role in the regulation of metabolism. A glucagon receptor has been previously characterized in the frog, Rana tigrina rugulosa, and the frog and human glucagon receptors have been shown to possess similar binding affinities toward human glucagon. To study the structural evolution of glucagon peptide and its receptor in vertebrates, in the current study, a proglucagon cDNA from the same frog species was cloned. Interestingly, in contrast to the mammalian proglucagons that contain only one GLP-1 peptide, the frog proglucagon cDNA encodes two GLP-1 peptides (GLP-1A and GLP-1B) in addition to a glucagon peptide and a glucagon-like peptide 2 (GLP-2). By reverse transcriptase-PCR (RT-PCR) analysis, the proglucagon gene expression was widely detected in the brain, colon, small intestine, liver, lung, and pancreas, suggesting that the proglucagon-derived peptides have diverse functions in frogs. Moreover, tissue-specific alternative mRNA splicing was observed in the brain, colon, and pancreas. In these tissues, proglucagon transcripts with a 135 bp in frame deletion encoding GLP-1A were found. This splicing event in R. tigrina rugulosa is novel because it deletes a GLP-1 encoding sequence instead of the GLP-2 observed in other vertebrates. These findings should enhance understanding of the proglucagon evolution, structure, and expression in vertebrates. PMID:11703080

  4. The advancement of biological research in amphibian culture in China%中国养殖的两栖动物生物学研究进展

    Institute of Scientific and Technical Information of China (English)

    刘焕亮

    2004-01-01

    综合论述了中国养殖的6种主要两栖动物:虎纹蛙Rana tigrina rugulosa Wiegmann、棘胸蛙Rana spinosa David、中国林蛙Rana temporaria chensinensis David、牛蛙Rana catesbeiana Shaw、猪蛙Rana grylio和中国大鲵Megalobatrachus davidianus Blanchara的生物学研究成果,包括养殖种类与地理分布,栖息习性,对盐度、温度、湿度、溶解氧、pH值的适应,摄食方式与食物组成,生长与繁殖生物学;展望了其生物学研究前景.

  5. Rações comerciais e o rendimento de carcaça e subprodutos de rã-touro Commercial food and the carcass yield and by-products of bullfrog

    Directory of Open Access Journals (Sweden)

    Alex Poeta Casali

    2005-10-01

    Full Text Available Objetivou-se avaliar o efeito do sexo e do uso de quatro rações comerciais extrusadas (R1, R2, R3 e R4 e uma ração peletizada (R5 sobre o rendimento de carcaça e aproveitamento de subprodutos da ranicultura, após 56 dias de experimentação. As rações comerciais eram recomendadas para diferentes espécies e fases de desenvolvimento animal, a saber: R1 = para rãs (na fase inicial, imagos; R2 = para peixes onívoros (em fase inicial; R3 = para trutas (peixe carnívoro na fase de crescimento; e R4 = para trutas (na fase inicial. Foram analisados os teores (% de matéria seca (MS, proteína bruta (PB, extrato etéreo (EE, fibra bruta (FB e matéria mineral (MM das rações. Foram utilizadas 80 rãs-touro com peso médio inicial de 51,57g distribuídas em um delineamento em blocos casualizados em esquema fatorial (cinco rações X dois sexos com oito repetições de uma rã por unidade experimental. Não houve significância na interação entre os fatores para todas as variáveis analisadas. Os menores valores de rendimento de carcaça foram observados nos animais que receberam a ração R3, sendo as demais iguais. No aproveitamento de subprodutos, destacou-se a ração R1, que proporcionou maior peso de fígado e descartes, e a ração R4, com maior peso de fígado e corpo gorduroso. O sexo dos animais apenas influenciou no aproveitamento de descartes, sendo que os machos proporcionaram maiores médias.The objective was to evaluate the effect of the sex and the use of four commercial extruded foods (R1, R2, R3, and R4 and a pelleted food (R5 on the carcass yield and the by-product utilization of the bullfrog culture, after 56 days of experimentation. The commercial foods were recommended to different species or phases of growth: R1 = for frogs in the initial phase; R2 = for omnivorous fish in the initial phase; R3 = for trout (carnivorous fish in phase of growth; and R4 = for trout in initial phase. The chemical composition (DM, CP, EE, CF

  6. 哈蟆油非水溶性成分抗疲劳保健功能研究%Study on Anti-fatigue Function of Non-Water-Soluble Components of OVIDUCTUS RANAE

    Institute of Scientific and Technical Information of China (English)

    王涵; 赵雨; 张梅; 幺宝金; 张鑫

    2011-01-01

    [目的]研究哈蟆油(OVIDVCTUS RANAE)非水溶性成分的抗疲劳作用.[方法]以低、中、高(0.25、0.5、1.0g/kg)3个剂量的哈蟆油非水溶性成分连续灌胃小鼠30 d,空白对照组给予等量的蒸馏水,测定小鼠负重游泳时间、血清尿素、肝糖原和血乳酸含量.[结果]哈蟆油非水溶性成分中剂量组小鼠的游泳时间明显长于对照组(P<0.05);各剂量组小鼠肝糖原含量均明显高于对照组(P<0.05);中、高剂量组小鼠运动后的血乳酸曲线下面积均小于对照组(P<0.05);各剂量组小鼠运动后血清尿素氮含量无明显改变.[结论]哈蟆油非水溶性成分具有抗疲劳作用.%[Objective] The aim was to study the anti-fatigue effect of the non-water-soluble components of OVIDUCTUS RANAE. [ Methods] The mice were divided into the low,medium and high dose groups and negative control group at random. Weight loaded swimming time,urea nitrogen ,hepatic glycogen content,blood lactate were determined after giving test substances by intragastrical gavage for 30 days. [ Results] The non-water-soluble components of OVIDUCTUS RANAE in medium dose groups obviously prolonged small mice swimming time (P <0. 05). Each group can made hepatic glycogen obviously improved and compared with blank observe group,it had obvious differences (P<0. 05). Middle and high dose groups after exercise, blood lactic area under the curve was less than the control group (P<0.05). [ Conclusion] The non-water-soluble components of OVIDUCTUS RANAE had the function of anti-fatigue.

  7. 林蛙油对游泳训练小鼠腓肠肌保护作用研究%The Protective Effect of Rana Oil on Swimming Trained Mice Gastrocnemius

    Institute of Scientific and Technical Information of China (English)

    张平; 张岚; 鲍九枝; 李松哲

    2013-01-01

      探讨林蛙油对运动训练小鼠腓肠肌自由基代谢和超微结构的影响,为林蛙油的应用和开发提供实验依据。以ICR小鼠为研究对象,通过建立灌服林蛙油小鼠递增游泳训练和游泳力竭模型,测定小鼠力竭游泳时间、腓肠肌SOD活性、MDA含量和小鼠腓肠肌超微结构的变化。林蛙油能延长小鼠力竭游泳时间,与运动组相比,林蛙油中、高剂量组有显著差异(p<0.01)。运动组SOD活性显著降低,与安静组比较,有显著差异(p<0.01);与林蛙油各剂量组比较,中、高剂量组有显著差异(p<0.05)。运动组MDA的含量最高,与安静组比较,有显著异(p<0.01)与林蛙油各剂量组比较,均有显著异(p<0.01)。小鼠腓肠肌组织超微结构的观察表明,运动组肌原纤维上肌节结构可辨,但呈致密状,线粒体嵴断裂,呈空化状,林蛙油组损伤程度小于运动组。林蛙油可显著提高小鼠腓肠肌组织抗自由基氧化的功能,对运动造成的腓肠肌组织超微结构的损伤有明显的保护作用,对小鼠运动能力的提高有很好的作用。%To explore the impact of Rana oil on trained mice Gastrocnemius free radical metabolism and ultrastructure, provided the experimental basis for the application and development of Rana oil. The research aimed to establish the oil Rana mice fed the incremental swimming training and exhaustive swimming model. Changes of mice swimming exhausted time, gastrocnemius muscle SOD activity, MDA content and gastrocnemius muscle ultrastructure was measured. The Rana oil can extend the swimming exhausted time of mice, compared with the trained group, Rana oil of high and medium dose group had a significant difference (p<0.01). SOD activity in the trained group significantly reduced, compared with the quiet group, had a significant difference (p<0.01);comparison with Rana oil each dose group, the high and medium dose

  8. Comparison of Morphological and Karyotypical Characters Between Rana tigrian rugulosa from Shiping and Yuanjiang of Yunnan%云南石屏和元江虎纹蛙外部形态与核型比较

    Institute of Scientific and Technical Information of China (English)

    杨丽萍; 周伟; 杨红燕; 李明会

    2011-01-01

    对采自云南石屏和元江的虎纹蛙进行外部形态特征和染色体核型分析.结果表明:元江虎纹蛙体形、体质量均明显大于石屏,其中,后肢全长、胫长、鼓膜宽、头宽等指标差异显著;两地虎纹蛙核型均为2n=26(5L+8M+0s),NF=52;石屏虎纹蛙的第3号为亚中部着丝点染色体(SM),其余为中部着丝点染色体(M),次缢痕位于6 p;元江虎纹蛙第3、6和8号为SM染色体,其余为M染色体,在3 p和6 p上具有不明显的次缢痕;显示不同地区虎纹蛙形态和核型均存在差异,推测石屏和元江产虎纹蛙可能是同种中的不同地理居群.%The morphological characters and karyotype of Rana tigrian rugulosa were analyzed using samples from Shiping and Yuanjiang of Yunnan. The results demonstrate that Rana tigrian rugulosa from Yuanjiang was big ger and got more weight than Shiping ones. Morphological characters such as length of hind limb, length of tibia, eardrum width and head width were significantly different between Yuanjiang and Shiping ones. Samples from dif ferent locations enjoyed the same karyotype : 2n = 26(5L +8M +0s) , NF =52. The chromosome No. 3 of Rana ti grian rugulosa from Shiping was SM , while the rest chromosomes were M , and the secondary constriction located on 6p. The chromosome No.3, 6 and 8 from Yunjiang were SM, the rest were M, and the unobvious secondary con striction located on 3p and 6p. It was significant different at morphological characters and karyotype between Yuan jiang and Shiping samples. Yuanjiang and Shiping samples might be speculated as the geographical groups of Rana tigrian rugulosa.

  9. Una especie nueva de rana arbórea del género Hyloscirtus (Amphibia: Anura: Hylidae de la Cordillera del Cóndor

    Directory of Open Access Journals (Sweden)

    Ana Almendáriz

    2014-01-01

    Full Text Available Las ranas ecuatorianas del género Hyloscirtus incluyen 16 especies descritas, de las cuales 11 pertenecen al grupo H. larinopygion. Su distribución se limita a los flancos de la Cordillera de los Andes, tanto al oriente como al occidente. Una evaluación de la herpetofauna en el sector meridional de la Cordillera del Cóndor (bosques montanos sobre mesetas de arenisca en la provincia de Zamora Chinchipe, Ecuador, condujo al descubrimiento de una especie nueva del grupo que describimos aquí como Hyloscirtus condor sp. nov.; se analizan los renacuajos, las llamadas de anuncio y se estima las relaciones filogenéticas de la especie nueva y de las especies relacionadas en base a nuevas secuencias de los genes mitocondriales 12S, tRNA Val y 16S, con un total de hasta 2508 bp. Los resultados muestran que el grupo H. larinopygion está conformado por dos clados, uno distribuido en los Andes norte y centro de Ecuador y el otro al sur. La nueva especie pertenece al clado sur y es hermana de H. tapichalaca y de una especie aparentemente no descrita de la Provincia Morona Santiago. La especie nueva difiere de sus congéneres por su patrón de coloración dorsal, que consiste de puntos amarillo obscuro en un fondo canela. Es la especie más grande del grupo H. larinopygion y comparte con H. tapichalaca la presencia de una espina prepólica grande y curvada y brazos hipertrofiados. La especie nueva habita un área remota y bien conservada de la Cordillera del Cóndor. El descubrimiento de ésta y otras especies nuevas del mismo lugar denota la importancia biológica del área y motivan al desarrollo de planes de conservación.

  10. Big mountains but small barriers: Population genetic structure of the Chinese wood frog (Rana chensinensis in the Tsinling and Daba Mountain region of northern China

    Directory of Open Access Journals (Sweden)

    Li Cheng

    2009-04-01

    Full Text Available Abstract Background Amphibians in general are poor dispersers and highly philopatric, and landscape features often have important impacts on their population genetic structure and dispersal patterns. Numerous studies have suggested that genetic differentiation among amphibian populations are particularly pronounced for populations separated by mountain ridges. The Tsinling Mountain range of northern China is a major mountain chain that forms the boundary between the Oriental and Palearctic zoogeographic realms. We studied the population structure of the Chinese wood frog (Rana chensinensis to test whether the Tsinling Mountains and the nearby Daba Mountains impose major barriers to gene flow. Results Using 13 polymorphic microsatellite DNA loci, 523 individuals from 12 breeding sites with geographical distances ranging from 2.6 to 422.8 kilometers were examined. Substantial genetic diversity was detected at all sites with an average of 25.5 alleles per locus and an expected heterozygosity ranging from 0.504 to 0.855, and two peripheral populations revealed significantly lower genetic diversity than the central populations. In addition, the genetic differentiation among the central populations was statistically significant, with pairwise FST values ranging from 0.0175 to 0.1625 with an average of 0.0878. Furthermore, hierarchical AMOVA analysis attributed most genetic variation to the within-population component, and the between-population variation can largely be explained by isolation-by-distance. None of the putative barriers detected from genetic data coincided with the location of the Tsinling Mountains. Conclusion The Tsinling and Daba Mountains revealed no significant impact on the population genetic structure of R. chensinensis. High population connectivity and extensive juvenile dispersal may account for the significant, but moderate differentiation between populations. Chinese wood frogs are able to use streams as breeding sites at high

  11. Spatial Amphibian Impact Assessment – a management tool for assessment of road effects on regional populations of Moor frogs (Rana arvalis

    Directory of Open Access Journals (Sweden)

    Maj-Britt Pontoppidan

    2013-11-01

    a case study dedicated to the Moor frog (Rana arvalis.

  12. Study on the anti-fatigue function of water-miscible total proteins from Oviductus Ranae%哈蟆油水溶性总蛋白抗疲劳活性的研究

    Institute of Scientific and Technical Information of China (English)

    张梅; 赵雨; 李芸彤; 幺宝金; 曲晓波

    2011-01-01

    研究了哈蟆油水溶性总蛋白的抗疲劳药理活性。采用中性缓冲液浸提,硫酸铵沉淀法制备哈蟆油水溶性总蛋白。设立哈蟆油水溶性总蛋白低、中、高三个剂量组(0.075、0.15、0.30g/kg),同时设立空白对照组,小鼠灌胃给药30d。观察小鼠体重、负重游泳时间、尿素氮含量、肝糖原含量、血乳酸含量等指标的变化。实验结果表明,哈蟆油水溶性总蛋白可延长小鼠负重游泳时间,降低血清尿素氮含量,显著增加肝糖原含量,显著降低血乳酸含量,对小鼠的体重无明显影响。证明了哈蟆油水溶性总蛋白具有一定的抗疲劳作用。%The pharmacological activity of water-miscible total proteins from Oviduetus Ranae was studied.Prepared water-miscible total proteins by neutral buffer extraction and ammonium sulfate precipitation.Low,medium,high(0.075,0.15,0.30g/kg)dose of water-miscible total proteins and a blank dose had been applied to mice for 30d continuously.The change of body weight of mice,swimming time,urea nitrogen,hepatic glycogen,and blood lactic acid content were observed.The results showed that the water-miscible total proteins of Oviductus Ranae could extend the swimming time of mice,significantly increase liver glycogen contents,significantly lower blood lactate levels,and had no significant effect on body weight of mice.The results proved the water-miscible total proteins of Oviductus Ranae had anti-fatigue effect.

  13. Sodium flux ratio through the amiloride-sensitive entry pathway in frog skin

    OpenAIRE

    1983-01-01

    The sodium flux ratio of the amiloride-sensitive Na+ channel in the apical membrane of in vitro Rana catesbeiana skin has been evaluated at different sodium concentrations and membrane potentials in sulfate Ringer solution. Amiloride-sensitive unidirectional influxes and effluxes were determined as the difference between bidirectional 22Na and 24Na fluxes simultaneously measured in the absence and presence of 10(-4) M amiloride in the external bathing solution. Amiloride- sensitive Na+ efflux...

  14. Primer registro de una población asilvestrada de rana toro (Lithobates catesbeianus en la Provincia de Córdoba, Argentina: Notas sobre la biología de la especie

    Directory of Open Access Journals (Sweden)

    Akmentins, Mauricio S.

    2008-12-01

    Full Text Available En Argentina se ha constatado la presencia de poblaciones asilvestradas de Lithobates catesbeianus en las provincias de San Juan (Sanabria et al., 2005 y de Misiones (Pereyra et al., 2006. Las ranas toro pueden eliminar a los anfibios nativos directamente a través de predación o competencia por interferencia, o indirectamente por competencia por explotación, modificación del comportamiento, alteración del hábitat o introducción de enfermedades o parásitos (Boone et al., 2004. El presente trabajo se realizó en la localidad de Agua de las Piedras (30º48' 46,2"S; 64º12'57,9"O; 760 msnm, la cual se encuentra a 65 km al norte de la ciudad de Córdoba, provincia de Córdoba, Argentina.

  15. Distribución y abundancia de Craugastor vulcani: una especie de rana en riesgo de Los Tuxtlas, Veracruz, México Distribution and abundance of Craugastor vulcani: an endangered frog species from Los Tuxtlas, Veracruz, Mexico

    OpenAIRE

    Eduardo Pineda; Clara A. Rodríguez-Mendoza

    2010-01-01

    En México, más de la mitad de las especies de anfibios están amenazadas y de la mayoría no se genera información que permita conocer el estatus en el que se encuentran sus poblaciones. En este trabajo se evaluó la distribución y abundancia de Craugastor vulcani, una rana endémica de la sierra de Los Tuxtlas Veracruz que se encuentra en riesgo de extinción, en función de la transformación de la selva. Para este trabajo, se consultaron bases de datos de registros históricos y se muestrearon 12 ...

  16. 虎纹蛙病毒体外培养及其理化特性%In vitro culture and physico-chemical properties of a virus isolated from diseased Rana tigrina rugulosa

    Institute of Scientific and Technical Information of China (English)

    王晓红; 翁少萍; 何建国

    2002-01-01

    从发病濒死的虎纹蛙(Rana tigrina rugulosa)蝌蚪中分离到一种病毒.在25℃条件下,该病毒能在鲤鱼表皮瘤细胞系(EPC),胖头鱥肌肉细胞系(FHM)和草鱼性腺细胞系(CO)三种鱼类细胞上产生空斑状的细胞病理变化(CPE).该病毒对氯仿,热(56℃,30min)和酸(pH3)敏感.其体外培养的适合增殖温度范围为20~30℃.电镜下观察,病毒为对称的二十面体,切面正六边形,对角直径125nm左右.

  17. pH值和温度对虎纹蛙消化系统蛋白酶活力的影响%EFFECTS OF pH AND TEMPERATURE ON THE PROTEASE ACTIVITY IN THE DIGESTIVE SYSTEM OF RANA RUGULOSA

    Institute of Scientific and Technical Information of China (English)

    张盛周; 朱升学; 佟媛; 张荣; 樊爱绪

    2005-01-01

    采用福林-酚试剂法,就pH值和温度对虎纹蛙(Rana rugulosa)消化系统蛋白酶活力的影响进行了研究.结果表明,虎纹蛙食道、胃、前肠、后肠、直肠和胰脏蛋白酶的最适pH值分别为1.5、1.5、7.4、7.4、7.4和9.6,最适温度则均为50℃.文中对蛙类的人工养殖提出了几点建议.

  18. 二种除草剂对虎纹蛙蝌蚪的毒性研究%A Study on The Toxicity of Two Kinds of Herbicides to Tadpole of Rana rugulosa

    Institute of Scientific and Technical Information of China (English)

    施时迪; 邵晨

    2006-01-01

    研究了二种常用除草剂施田补和百草枯对虎纹蛙Rana rugulosa蝌蚪的毒性.结果表明:随着除草剂浓度的增大,虎纹蛙蝌蚪的死亡率随之提高;百草枯对虎纹蛙蝌蚪的毒性大于施田补,施田补和百草枯对虎纹蛙蝌蚪72 h的半致死浓度(IC50)分别为1.23×10-6L和1.02×10-6L.本研究结果对于合理使用除草剂以有效保护虎纹蛙资源有积极意义.

  19. Estufas climatizadas para experimentos ambientais com rãs, em gaiolas Acclimatized incubators for environmental experiments with frogs, in cages

    Directory of Open Access Journals (Sweden)

    Mario Roberto Chim Figueiredo

    2001-07-01

    12/12 hours of light/hours of darkness (h L/D were available to frogs adaptation during 15 days before each experiment. The treatments consisted to simulate environments with temperatures varying from 20 to 35ºC and photoperiods of 8/16, 12/12 and 16/8 h L/D. They were accomplished experiments with bullfrog (Rana catesbeiana Shaw, 1802 and with butterfrog (Leptodactylus ocellatus Linnaeus, 1758. In these incubators it was possible to estimate that: a the highest weight gain of bullfrog was obtained between 27.6 and 29.7ºC, with better growth between 28.2 and 30.1ºC; for butterfrog the best gain and alimentary conversion were verified at 28.6 and 28ºC, respectively; b temperature interact with photoperiod affecting the frogs performance and gonadal development; c at 27.7ºC (temperature of thermal comfort there will be less frogs inside of water; d the highest cloacal temperature: 32.1ºC, in the dry part, and 33.8ºC, inside of water, at 35ºC, evidenced the bullfrog thermoregulation; e the tetraiodotironine (T4 level in the plasm decreases in the temperature of thermal comfort; f butterfrog was conditioned to the routine handling, coming around feeder at eater time.

  20. Efecto de ocho Protocolos de Inducción Hormonal sobre la Reproducción de Ranas Venenosas Dendrobates truncatus (Cope, 1861 en el Parque Recreativo y Zoológico Piscilago

    Directory of Open Access Journals (Sweden)

    J Alexander Franco

    2012-06-01

    Full Text Available La difícil reproducción en cautiverio de ranas del género Dendrobates y su importanciapara la investigación médica y la industria de mascotas, han llevando a través del trafico al declive a sus poblaciones naturales, generando la necesidad de investigar el potencial zootécnico y la conservación de estas especies. Este estudio evaluó el efecto de ocho protocolos de inducción hormonal sobre la reproducción de ranas Dendrobates truncatus, se realizó en el Parque recreativo y zoológico Piscilago con 16 individuos de su colección, estos fueron pesados, sexados, medidos y fotografiados, se distribuyeron de a parejas en cajas plásticas de 30x40x20cm adecuadas como terrarios y se alimentaron a diario con insectos (tenebrios y termitas registrando temperatura y humedad tres veces al día, además se utilizo un período de acostumbramiento de 10 días. Los protocolos se basaron en la combinación de Chorulon® (gonadotropina coriónica humana, HCG y Merional® (gonadotropina menopaúsica humana, HMG a diferentes cantidades, número e intervalos entre aplicaciones, aplicando dos protocolos cada 10 días con 4 parejas por protocolo, para la manipulación se utilizaron guantes de látex sin talco y la inyección se realizó en el saco dorsal linfático con jeringas de 0,5mL y agujas de 12mm calibre 30G. Para los factores ambientales los resultados de temperatura y humedad fueron en promedio de 27,2°C y 77,8% respectivamente, en cuanto a los protocolos, ninguno logró inducir la reproducción, incluyendo llamados de cortejo, amplexos, ovulaciones y/o espermiaciones. Sin embargo, los protocolos hormonales no generaron ningún efecto negativo evidente sobre la salud de los animales. Los protocolos de inducción hormonal se utilizan para la conservación y zootecnia de algunos anfibios y aunque en este caso no funcionaron, se obtuvieron algunas experiencias de interés. Es necesario  llevar a cabo más estudios con diferentes protocolos u

  1. Comparison of Genetic Diversity between Frog Rana tigrina rugulosa and Frog R. tigrina cantor%中国虎纹蛙与泰国虎纹蛙的遗传多样性比较

    Institute of Scientific and Technical Information of China (English)

    刘丽; 刘楚吾; 林东; 梁伟峰

    2005-01-01

    本文应用RAPD技术,研究了中国虎纹蛙(Rana tigrina rugulosa)和泰国虎纹蛙(R. tigrina cantor)的种内种间遗传多样性及种质特异性分子标记,结果表明:中国虎纹蛙和泰国虎纹蛙多态位点比例(P)分别为53.77%和70.79% ;遗传多样性指数(H)分别为0.1345和0.1780;种间的遗传相似系数(S)为0.4238,遗传距离(D)为0.6613.两种虎纹蛙遗传多样性都较丰富,但中国虎纹蛙的遗传变异程度较泰国虎纹蛙低.在OPA、OPF、OPP、OPZ几个系列随机引物的扩增中得到了可用于鉴别两种蛙的12条特异性谱带.

  2. Distribution of five types of gastrointestinal hormone immunoreactive cells in the skin of rana rugulosa%5种胃肠激素免疫阳性细胞在虎纹蛙皮肤中的分布

    Institute of Scientific and Technical Information of China (English)

    李洋; 李昌春; 金磊; 戴光云; 张盛周

    2010-01-01

    目的:对虎纹蛙(rana rugulosa)皮肤中5种胃肠激素免疫阳性细胞进行鉴别与定位.方法:应用过氧化物酶标记的链霉卵白素(S-P)免疫细胞化学方法.结果:在虎纹蛙皮肤中检测出了5-羟色胺(5-HT)、胃泌素(GAS)、胰高血糖素(GLU)、胰多肽(PP)和生长抑素(SS)等5种胃肠激素免疫阳性细胞.阳性细胞主要分布于皮肤的表皮层和黏液腺中,颗粒腺中未见分布.GAS和GLU免疫阳性细胞在背部皮肤中的分布密度大于腹部,背部皮肤中免疫阳性反应亦强于腹部;5-HT、PP和SS免疫阳性细胞则在腹部皮肤中的分布密度大于背部,腹部皮肤中免疫阳性反应亦强于背部.结论:虎纹蛙皮肤细胞可表达多种胃肠激素免疫阳性物质,其在背腹部皮肤中含量不同.

  3. Construction of Eukaryotic Expression Vector with Rana Antimicrobial Peptides Gene Temporin-lCEa%中国林蛙抗菌肽Temporin-1CEa基因的真核表达载体构建。

    Institute of Scientific and Technical Information of China (English)

    张志崇; 王春生; 张秋婷; 朴善花; 苗向阳; 安铁洙

    2012-01-01

    In order to establish a method to get a large number of antimicrobial peptides from Rana chensinensis,a series of experiments were conducted as follows.According to Chinese frog skin antimicrobial peptides Temporin-1CEa gene mRNA sequence(EU624139) in GenBank,a pair of specific primers were designed and cDNA was obtained from Chinese forest frog skin RNA by reverse transcription.Temporin-1CEa gene coding sequence was amplified using the cDNA,and linked with pEASY-T3 cloning vector.The GFP gene was inserted into the recombinant plasmid Tem-T3 by molecular methods.The Tem-GFP fragment was linked with eukaryotic expression vector pcDNA3.1,and Tem-GFP-pcDNA3.1 recombinant plasmid was achieved finally.Using of lipid infection method,the plasmids were transfected into sheep fibroblast cells,the green fluorescence was observed under a fluorescence microscope after 48 h.qPCR data showed that Tem-GFP fusion protein expression level of transfected Tem-GFP-pcDNA3.1 sheep fibroblasts increased about 300 folds than that of the control group.This study supplied the technical basis for developing mammary gland bioreactor of expressing Temporin-1CEa gene.%为了建立大量获取中国林蛙抗菌肽的方法,根据GenBank中的中国林蛙皮肤抗菌肽Temporin-1CEa基因的mRNA序列(EU624139)设计一对特异性引物,以提取的中国林蛙皮肤总RNA反转录出的cDNA为模板,将扩增的编码序列与pEASY-T3克隆载体连接获得Tem-T3;利用酶切、连接等分子生物学手段,将GFP基因连入Tem-T3克隆载体,再经酶切获得Tem-GFP片段,并插入真核表达载体pcDNA3.1,最终得到Tem-GFP-pcD-NA3.1重组质粒;利用脂质体转染法将该质粒转入绵羊成纤维细胞,48 h后可在荧光倒置显微镜下观察到GFP的绿色荧光表达;qPCR数据分析显示,与对照组相比,转染Tem-GFP-pcDNA3.1的绵羊成纤维细胞中融合蛋白Tem-GFP的表达量可提高约300倍。本研究为构建Temporin-1CEa基因山羊乳腺特异表达载体提供依据。

  4. IN VITRO STUDIES ON GONADOTROPIN-RELEASING HORMONE SECRETION IN RANA RUGULOSA%虎纹蛙促性腺激素释放激素分泌调节的离体研究

    Institute of Scientific and Technical Information of China (English)

    李远友; 林浩然

    2002-01-01

    利用离体静态孵育系统和放射免疫测定法,研究了性成熟的虎纹蛙雌蛙离体的视前-下丘脑-正中隆起(P-H-ME)片段促性腺激素释放激素(GnRH)的分泌调节.结果表明:γ-氨基丁酸(GABA)对成熟前期蛙离体P-H-ME片段的哺乳类GnRH(mGnRH)的释放有显著的刺激作用;随着GABA作用浓度的增加,刺激作用逐渐增强.100 μmol/L的多巴胺(DA)及1 μmol/L 和10 μmol/L的雌二醇(E2)则显著抑制鸡Ⅱ GnRH (cGnRH-Ⅱ)的释放.10 μmol/L 和100 μmol/L的睾酮(T)以及10 μmol/L的E2显著刺激冬眠期蛙P-H-ME片段mGnRH的释放.这些结果说明,GABA、DA及E2和T对虎纹蛙GnRH的释放有直接的调节作用.%In vitro release of gonadotropin-releasing hormone (GnRH) from the slices of the brain preoptic-hypothalamus-median eminence (P-H-ME) region of adult Rana rugulosa females was studied by using a static incubation system and raidoimmunoassay (RIA). γ-aminobutyric acid (GABA) at 0.1~10 μmol/L (significantly) stimulated the release of mammalian GnRH (mGnRH) from the slices of P-H-ME of sexually pre-mature frog, the stimulatory action was enhanced with the increasing concentrations of GABA, and was significant at 1 μmol/L or 10 μmol/L; 100 μmol/L dopamine (DA) and 1 μmol/L or 10 μmol/L estradiol (E2) markedly inhibited the release of chicken-Ⅱ GnRH (cGnRH-Ⅱ). Both 10 μmol/L or 100 μmol/L testosterone (T) and 100 μmol/L E2 significantly stimulated the release of mGnRH from the slices of P-H-ME of hibernating frog. These results demonstrate that GABA, DA, E2 and T may have direct regulatory action on GnRH release from the brain of R.rugulosa.

  5. Potential for Loss of Breeding Habitat for Imperiled Mountain Yellow-legged Frog ( Rana muscosa) in High Sierra Nevada Mountain Water Bodies due to Reduced Snowpack: Interaction of Climate Change and an Introduced Predator

    Science.gov (United States)

    Lacan, I.; Matthews, K. R.

    2005-12-01

    Year to year variation in snowpack (20-200% average) and summer rain create large fluctuations in the volume of water in ponds and small lakes of the higher elevation (> 3000 m) Sierra Nevada. These water bodies are critical habitat for the imperiled mountain yellow-legged frog, Rana muscosa, which has decreased in abundance by 90% during the past century, due in part to the loss of suitable habitat and introduction of a fish predator (trout, Oncorhynchus spp.). Climate change is predicted to reduce the amount of snowpack, potentially impacting amphibian habitats throughout the Sierra Nevada by further reducing the lake and pond water levels and resulting in drying of small lakes during the summer. Mountain yellow-legged frogs are closely tied to water during all life stages, and are unique in having a three- to four-year tadpole phase. Thus, tadpole survival and future recruitment of adult frogs requires adequate water in lakes and ponds throughout the year, but larger lakes are populated with fish that prey on frogs and tadpoles. Thus, most successful frog breeding occurs in warm, shallow, fishless ponds that undergo wide fluctuations in volume. These water bodies would be most susceptible to the potential climate change effects of reduced snowpack, possibly resulting in lower tadpole survival. This study explores the link between the changes in water availability -- including complete pond drying -- and the abundance and recruitment of mountain yellow-legged frog in Dusy Basin, Kings Canyon National Park, California, USA. We propose using the low-snowpack years (1999, 2002, 2004) as comparative case studies to predict future effects of climate change on aquatic habitat availability and amphibian abundance and survival. To quantify the year to year variation and changes in water volume available to amphibians, we initiated GPS lake mapping in 2002 to quantify water volumes, water surface area, and shoreline length. We tracked these changes by repeated mapping of

  6. Distribución y abundancia de Craugastor vulcani: una especie de rana en riesgo de Los Tuxtlas, Veracruz, México Distribution and abundance of Craugastor vulcani: an endangered frog species from Los Tuxtlas, Veracruz, Mexico

    Directory of Open Access Journals (Sweden)

    Eduardo Pineda

    2010-04-01

    Full Text Available En México, más de la mitad de las especies de anfibios están amenazadas y de la mayoría no se genera información que permita conocer el estatus en el que se encuentran sus poblaciones. En este trabajo se evaluó la distribución y abundancia de Craugastor vulcani, una rana endémica de la sierra de Los Tuxtlas Veracruz que se encuentra en riesgo de extinción, en función de la transformación de la selva. Para este trabajo, se consultaron bases de datos de registros históricos y se muestrearon 12 sitios que representan ambientes comunes de la región. Se registró un total de 524 individuos, de los cuales el 77% se encontraron en fragmentos de selva, el 20% en remanentes riparios y sólo el 3% en potreros. La mayor abundancia (62% se registró durante la época seca del año. La distribución conocida de C. vulcani está sesgada hacia el norte de la sierra, existe poca información sobre su presencia en la porción sur. La permanencia de la especie en la zona parece depender de los pocos fragmentos de bosque existentes. El aumento en el número, área y conectividad de tales remanentes son algunas de las medidas necesarias para conservar ésta y otras especies amenazadas en la región.More than a half of all amphibian species occurring in Mexico are threatened, and for most of them there is no current information to assess the status of their populations. Craugastor vulcani is an endemic frog from the Los Tuxtlas mountains, Veracruz, and it is classified as an endangered species. We examine the distribution and abundance of C. vulcani as a function of rainforest transformation in Los Tuxtlas. We consulted historical records in databases and sampled 12 sites representing common habitats of the region. We recorded a total of 524 individuals of which 77% were found in rainforest fragments, 20% were collected in riparian remnants and just 3% in cattle pastures. Most individuals (62% were recorded during the dry season. The known distribution

  7. AcEST: BP917573 [AcEST

    Lifescience Database Archive (English)

    Full Text Available YMU001_000102_E11 336 Adiantum capillus-veneris mRNA. clone: YMU001_000102_E11. BP917573 CL2782C ... e N-methyltransferas... 31 2.2 sp|Q02777|THA_RANCA Thyroid ... hormone receptor alpha OS=Rana cates... 30 2.9 sp| ... S=Mus musculus GN=F... 30 3.8 sp|P18115|THAB_XENLA Thyroid ... hormone receptor alpha-B OS=Xenopus... 29 6.4 sp|P ... 15204|THAA_XENLA Thyroid ... hormone receptor alpha-A OS=Xenopus... 29 6.4 sp|Q ... SPRDRRHHDYRRSPSYSEWSPHDRS 453 >sp|Q02777|THA_RANCA Thyroid ... hormone receptor alpha OS=Rana catesbeiana GN=thra ...

  8. 多巴胺、雌二醇及睾酮对虎纹蛙离体脑垂体促性腺激素分泌的影响%EFFECTS OF DOPAMINE,ESTRADIOL AND TESTOSTERONE ON GONADOTROPIN RELEASE FROM THE PITUITARY FRAGMENTS OF Rana rugulosa

    Institute of Scientific and Technical Information of China (English)

    李远友; 林浩然

    2000-01-01

    To understand the regulatory mechanisms of gonadotropin secretion in Rana rugulosa, this study investigated the effects of dopamina (DA), estradiol (E2) and testosterone (T) on the in vitro release of luteinizing hormone (LH) and follicle-stimulation hormone (FSH) from the pituitary fragments of female Rana rugulosa using a static incubation system and radio-immunoassay (RIA). The results indicated that DA at the concentration from 0.1 μmol/L to 10μmol/L inhibited the release of LH and FSH from the pituitary fragments of sexually pre-mature or hibernation individuals, and the inhibitory effects enhanced with increasing concentrations of DA. E2at 1 μmol/L and 10μmol/L significantly stim-ulated the release of LH of sexually pre-mature individuals, but inhibited their FSH release at 0.1μmol/L to 10 μmol/L; T had no obvious effects on their FSH release, but significantly inhibited their LH release at 10 μmol/L. Neither E2 nor T, at the concentration from 0.1 μmol/L to 100 μmol/L, had obvious effects on the release of LH and FSH of hibernation individuals. The data suggest that DA and sexual steroids may have direct regulatory actions on LH and FSH release at the pituitary level in Rana rugulosa, and the action of sexual sterlids may relate to the gonadal development stages (sea-sons).%为了解虎纹蛙促性腺激素分泌的调节机理,用离体静态培育系统和放射免疫测定法,研究了多巴胺(DA)、雌二醇(E2)和睾酮(T)对雌性虎纹蛙离体脑垂体薄片促黄体激素(LH)和促卵泡激素(FSH)分泌活动的影响.结果表明:0.1~10μmol/L的DA对成熟前期和冬眠期虎纹蛙离体脑垂体薄片的LH及FSH的释放都有抑制作用,并且随着DA浓度的增加,抑制作用逐渐增强.1和10μmol/L的E2显著刺激成熟前期蛙LH的释放,而0.1~10μmol/L的E2显著抑制其FSH的释放;T对其FSH的释放无显著影响,但10μmol/L的T显著抑制其LH释放.0.1~100μmol/L的E2或T对冬眠期蛙LH和FSH的释放均

  9. Isolation, identification and drug sensitivity tests of Proteus mirabilis from rotten-skin disease of Rana spinosa%棘胸蛙烂皮病奇异变形杆菌的分离、鉴定及对药物敏感性研究

    Institute of Scientific and Technical Information of China (English)

    王瑞君; 熊筱娟

    2012-01-01

    从患烂皮病的棘胸蛙(Rana spinosa)中分离到一株致病菌,通过形态学、生理生化试验等方法鉴定该致病菌株为奇异变形杆菌(Proteus mirabilis).同时,通过抑菌圈法研究了该菌株对11种抗生素、11种中草药、4种消毒剂的敏感性.结果显示:该菌株对头孢曲松、阿莫西林、链霉素、诺氟沙星、庆大霉素、卡那霉素、氯霉素等抗生素敏感,对四环素、红霉素不敏感;未观察到黄芪、茵陈对该菌的抑制作用,忍冬藤抑菌效果最好,其次依次为紫花地丁、金银花与甘草、鱼腥草、大青叶与柴胡、陈皮、黄连;致病菌株对消毒剂的敏感性依次为:高锰酸钾>三氯异氰脲酸>硫酸铜>氧化钙.%Pathogenic strain originated from the rotten-skin disease of Rana spinosa was isolated. The isolated strain was I-dentified as Proteus mirabilis by its morphological and biochemical properties. At the same time, the susceptibility of isolated strain to antibiotics, Chinese herbal medicine and disinfectant was studied by zone of inhibition testing. Results showed: it was sensitive to ceftriaxone sodium, amoxicillin, streptomyclin, norfloxacin, gentamycin sulfate, kanamycin and chloroamphenicol; it was not sensitive to tetracycline and erythromyclin. Astragalus membranaceus and Artemisiac apil-laris Thunb had less inhibition to this strain. The bigger inhibition zone is Lonicera japonica, Viola philippica Car, Honeysuckle and Radix glycyrrhiza, Houttuynia cordata Thunb, halts indigotica Fortune and Radix Bupleuri, Pericarpium citri, Coptis chinensis Franch sorted by size. Inhibitory effect of these disinfectors.was: Potassium permanganate >Trichloro iso-cyanuric acid > Copper sulfate > Calcium oxide.

  10. Distortion product otoacoustic emissions provide clues to hearing mechanisms in the frog

    Science.gov (United States)

    Vassilakis, Pantelis; Narins, Peter M.

    2003-10-01

    Cubic distortion product otoacoustic emissions (DPOAEs) were recorded from 10 Rana pipiens and 10 Rana catesbeiana, 5 males and 5 females each. The I/O curves obtained from the amphibian papilla (AP) of both species are very similar to the respective mammalian curves, indicating that, like in the mammalian cochlea, there may be an amplification process active in the frog AP. The DPOAE level dependence on primary levels is also similar to the mammalian case, suggesting a mechanical structure in the frog inner ear may be functioning analogously to the mammalian basilar membrane. DPOAE audiograms were obtained for primary frequencies spanning the animals hearing range and levels determined by the previous experiments. R. catesbeiana produce stronger emissions than R. pipiens and, consistent with previously reported sexual dimorphism in the mammalian and anuran auditory systems, females from both species produce stronger emissions than males. Additionally, the 2f1-f2 DPOAE is generated primarily at the DPOAE frequency place, while the 2f2-f1 DPOAE is generated primarily at a frequency place between the primaries. This difference in mammalian and frog DPOAEs may be linked to an anatomical difference that results in the acoustic energy following opposite paths through the mammalian and frog inner ears. [Work supported by NIH Grant No. DC-00222 to Peter M. Narins.] a)Currently at De Paul Univ., School of Music, Chicago, IL 60614.

  11. BIOCONCENTRATION AND METABOLISM OF ALL-TRANS RETINOIC ACID BY RANA SYLVATICA AND RANA CLAMITANS TADPOLES

    Science.gov (United States)

    Retinoids, which are Vitamin A derivatives, are important signaling molecules that regulate processes critical for development in all vertebrates. The objective of our study was to examine uptake and metabolism of all-trans retinoic acid...

  12. Mathematical Modeling for the Optimum Enzymatic Hydrolysis of Rana Skin Collagen Peptide and Its Antioxidant Research%林蛙皮胶原蛋白肽酶解工艺数学建模及抗氧化作用的研究

    Institute of Scientific and Technical Information of China (English)

    邱芳萍; 王长周; 季晓枫

    2013-01-01

    The influencing factors in the enzyme solution process of Rana skin collagen peptide (LWT) were optimized by using the mathematical statistics and data fitting analysis method. And the relationship between the influencing factors and hydrolyzing degree in the enzyme solution process of LWT was established. And the best value hydrolysis degree (peak) was forecasted. Used polyacrylamide gel electrophoresis method to determine the molecular weight of LWT which was under 3 500. High performance liquid chromatogram showed that the purity was in the high level. In the antioxidant effect of LWT on liver damage of bromobenzene mice were studied. The results showed that LWT have the remarkable effect on reducing MDA content and the obvious effect on rising SOD vitality in mice liver tissue and have antioxidant effect.%采用数理统计和数据拟合分析方法对林蛙皮胶原蛋白肽(LWT)酶解过程中的影响因素进行优化,建立了LWT酶解过程中影响因素与水解度关系的数学模型,验证了水解度的最佳值(峰值).采用聚丙烯酰胺凝胶电泳方法证明LWT的相对分子质量在3 500以下,HPLC表明其纯度较高.研究了LWT对溴代苯小鼠肝损伤的抗氧化作用,结果表明:LWT具有显著降低小鼠肝组织中MDA质量分数和显著升高小鼠肝组织中SOD活力的作用,具有抗氧化作用.

  13. A comparative study on the secretory activity of the subcommissural organ in the European green frogs: Rana esculenta, rana lessonae and Rana ridibunda

    NARCIS (Netherlands)

    Diederen, J.H.B.; Vullings, H.G.B.

    1980-01-01

    1. 1. The subcommissural organ (SCO), present in all vertebrates, is situated in the roof of the third brain ventricle, and secretes into this ventricle a glycoproteinaceous, fibre-like structure, the liquor fibe (LF). 2. 2. The three forms of European green frogs diner from each other in the three

  14. Comparative ultrastructural analysis of two tortoise bladders, Testudo graeca and Geochelone carbonaria.

    Science.gov (United States)

    Strum, J M; Danon, D

    1976-01-01

    Urinary bladders from the desert tortoises, Testudo graeca and Geochelone carbonaria were removed at specific times during the year and species in all bladders examined: (1) granular cells, (2) mitochondria-rich cells, and (3) basal cells. Cells analogous to these three types have also been observed in amphibian bladders (from toad Bufo marinus and bullfrog, Rana catesbiana) and reptilian bladders (from Pseudemys scripta and Clemmys caspica). Both tortoises have an incomplete layer of basal cells so that the granular and mitochondria-rich cells extend from the lumen to the basement membrane: something was not observed in bladders from bullfrog or turtles. A flask-shaped light cell was observed in the Geochelone carbonaria bladder obtained in April. No counterpart of this cell was seen in the same species sacrificed in January, or in any of the Testudo graeca bladders, although a similar cell has been described in the turtle, Pseudemys scripta (Rosen, Expt. Molec. Path., 12: 286-296, '70). This study was undertaken to characterize the cell types present in tortoise bladder and to compare them with cell types in the bladder of the turtle, bullfrog and toad. PMID:1252017

  15. Dicty_cDB: Contig-U00933-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ductor muscle; &U55046_1(U55046... 51 1e-05 AJ287190_1( AJ287190 |pid:none) Radiomyces spectabilis partial ac...e) Lepeophtheirus salmonis Pacific fo... 51 1e-05 AF276076_1( AF276076 |pid:none) Ambystoma mexicanum cardiac ac...1e-05 AB179839_1( AB179839 |pid:none) Seriola quinqueradiata ACTB mRNA f... 51 1e-05 DQ666083_1( DQ666083 |pid:none) Artemia franci...83042_1( AB283042 |pid:none) Orgyia thyellina OtAct mRNA for cy... 51 1e-05 AY986487_1( AY986487 |pid:none) Rana catesbeiana cardiac...5 ) RecName: Full=Actin-104; Flags: Fragment; &U60494_1(U6... 51 1e-05 EF063572_1( EF063572 |pid:none) Actinidia delicio

  16. Cancer-selective induction of apotosis by leczyme

    Directory of Open Access Journals (Sweden)

    KazuoNitta

    2014-06-01

    Full Text Available Sialic acid-binding lectin (SBL is a multifunctional protein that is isolated from oocytes of Rana catesbeiana. It has both lectin and ribonuclease (enzyme properties, and therefore is called leczyme. We examined the antitumor effects of SBL and discovered that SBL has potential as a new type of anticancer drug. SBL causes a cancer-selective induction of apoptosis by multiple signaling pathways whereby RNA is its target. It is suggested that the mitochondrial pathway and endoplasmic reticulum stress-mediated pathway participate in SBL-induced signaling. The synergistic antitumor effects with other molecules, such as tumor necrosis factor-related apoptosis ligand (TRAIL and interferon γ (IFN-γ, have been reported. In this study, we summarize the effects of SBL and focus on its cancer-selective apoptotic properties. In addition, we present a possible explanation its cancer specificity.

  17. Dicty_cDB: Contig-U14507-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available : Full=41 kDa peptidyl-prolyl cis-trans isomeras... 139 6e-32 CP000918_1484( CP000918 |pid:none) Streptococcus pneumo... CP000480 |pid:none) Mycobacterium smegmatis str. MC2 ... 137 2e-31 AE005672_728( AE005672 |pid:none) Streptococcus pneumo...30 BT081948_1( BT081948 |pid:none) Rana catesbeiana clone rcat-evr-50... 133 6e-30 (Q6CBP4) RecName: Full=Peptidyl-prolyl cis-tran... 2e-28 CP000017_370( CP000017 |pid:none) Streptococcus pyogenes MGAS5005,... 128 2e-28 (P0C1I0) RecName: Full=Peptidyl-prolyl cis...C116510_1( BC116510 |pid:none) Danio rerio natural killer-tumor r... 124 2e-27 AF325026_1( AF325026 |pid:none) Arabidopsis thaliana

  18. Antipredator Behavioral Responses of Native and Exotic Tadpoles to Novel Predator

    Institute of Scientific and Technical Information of China (English)

    Fang ZHANG; Juan ZHAO; Yujie ZHANG; Kevin MESSENGER; Yong WANG

    2015-01-01

    Factors related to the invasion process, such as high abundance of invaders, residence time, and functional distinctiveness, are well documented, but less attention has been given to the effects of antipredator strategy of invasive species during colonization. In this study, we explored the antipredator strategy of an introduced species by comparing the predator avoidance behaviors of two native anuran species and one introduced (“exotic”) species in the presence of different predators. The two native anuran species used in the study were Black-spotted Pond FrogRana nigromaculata and Terrestrial Frog Rana limnocharis. The introduced (invasive) species used was American bullfrogLithobates catesbeianus. Chinese pond turtleChinemys reevesii, Red-backed rat snakeElaphe rufodorsata, and Big-headed turtle Platysternon megacephalum were used as predator species. Chinese pond turtles and Red-backed rat snakes are native predators of Black-spotted Pond Frogs and Terrestrial Frogs, while Big-headed turtles are novel (“unfamiliar”) to the two frogs. All three predator species are novel (“unfamiliar”) to the American bullfrog. The results show that tadpoles of the two native species displayed behaviors of recognizing the two native predators, but did not display the capability of identifying the novel predator. Results from our study also suggest that American bullfrog tadpoles exhibited strong antipredator behavioral responses by displaying the capability of identifying “unfamiliar” predators without cohabitation history and prior exposure to them. Such antipredator behavioral responses could have resulted in more favorable outcomes for an invading species during the invasive introductory process.

  19. Behavioural adaptations of Rana temporaria to cold climates.

    Science.gov (United States)

    Ludwig, Gerda; Sinsch, Ulrich; Pelster, Bernd

    2015-01-01

    Environmental conditions at the edge of a species' ecological optimum can exert great ecological or evolutionary pressure at local populations. For ectotherms like amphibians temperature is one of the most important abiotic factors of their environment as it influences directly their metabolism and sets limits to their distribution. Amphibians have evolved three ways to cope with sub-zero temperatures: freeze tolerance, freeze protection, freeze avoidance. The aim of this study was to assess which strategy common frogs at mid and high elevation use to survive and thrive in cold climates. In particular we (1) tested for the presence of physiological freeze protection, (2) evaluated autumnal activity and overwintering behaviour with respect to freeze avoidance and (3) assessed the importance of different high-elevation microhabitats for behavioural thermoregulation. Common frogs did not exhibit any signs of freeze protection when experiencing temperatures around 0 °C. Instead they retreated to open water for protection and overwintering. High elevation common frogs remained active for around the same period of time than their conspecifics at lower elevation. Our results suggest that at mid and high elevation common frogs use freeze avoidance alone to survive temperatures below 0 °C. The availability of warm microhabitats, such as rock or pasture, provides high elevation frogs with the opportunity of behavioural thermoregulation and thus allows them to remain active at temperatures at which common frogs at lower elevation cease activity. PMID:25774030

  20. Osmotic pressure of the cutaneous surface fluid of Rana esculenta

    DEFF Research Database (Denmark)

    Hviid Larsen, Erik; Ramløv, Hans

    /Kg, n = 16. Osmolality of lymph was, 239 ± 4 mosmol/Kg, n = 8. Thus the flow of water across the epidermis would be in the direction from CSF to the interstitial fluid driven by the above osmotic gradients and/or coupled to the inward active Na+ flux via the slightly hyperosmotic paracellular...

  1. Radioimmunoassay for plasma corticotropin in frogs (Rana esculenta L.)

    International Nuclear Information System (INIS)

    A radioimmunoassay technique has been developed for measuring frog plasma corticotropin (ACTH) without prior extraction. Using synthetic porcine ACTH as a reference standard, 131I-labeled synthetic human ACTH (sp act greater than 500 mCi/mg) as tracer and rabbit anti-porcine ACTH serum, the lower measurable value was estimated at about 4 pg ACTH. Only human and porcine ACTH, ACTH, and frog pituitary ACTH reacted with the rabbit anti-porcine ACTH serum. No cross-reactivity has been found with synthetic ACTH, αMSH, and bovine βMSH. Appearance of damaged 131I-h ACTH components after storage in plasma solutions was followed for 7 days. The conditions making it possible to reduce ACTH damage have been ascertained. The average plasma corticotropin level (+- CI) was found to be 38.8 +- 7.8 pg/ml without any significant difference between males and females. These results suggest that frog ACTH secretion has much in common with mammalian secretions

  2. The role of desensititation in decay time of miniature endplate currents in frogs Rana ridibunda and Rana temporaria

    Czech Academy of Sciences Publication Activity Database

    Giniatullin, R. A.; Talantova, M. V.; Vyskočil, František

    2001-01-01

    Roč. 39, č. 3 (2001), s. 287-292. ISSN 0168-0102 R&D Projects: GA AV ČR IAA7011902; GA MŠk VS97099; GA MŠk OK 267 Grant ostatní: RFBR(RU) 98-04-48044; INTAS(BE) 2000-1147 Institutional research plan: CEZ:AV0Z5011922 Keywords : frog * desensitisation * miniature endplate potential Subject RIV: ED - Physiology Impact factor: 1.770, year: 2001

  3. El declive de una población costera cantábrica de Rana bermeja (Rana temporaria

    Directory of Open Access Journals (Sweden)

    GOSA, A.

    1998-01-01

    Algunas de las características reproductoras de la población son de notable alargamiento de su periodo de puesta, que comienza a primeros de noviembre y puede extenderse hasta febrero y primeros de marzo ; la baja fecundidad de las hembras (media de 1006 huevos por puesta y la permanencia de los machos en los charcos donde se reproducen(algunos pasan en ellos hasta dos meses y medio.El pico reproductor medio para el periodo de estudio se produce en la segunda decena de diciembre, fecha en la que ya se ha hecho el 60% de la puesta total.

  4. First record of the chytrid fungus in Lithobates catesbeianus from Argentina: exotic species and conservation Primer registro del hongo quitridio en Lithobates catesbeianus de Argentina: especies exóticas y conservación

    Directory of Open Access Journals (Sweden)

    Romina Ghirardi

    2011-12-01

    Full Text Available Chytridiomycosis, a disease caused by the chytrid fungus Batrachochytrium dendrobatidis (B.d., is recognized as one of the major factors of amphibian decline. Global trade of amphibians has been identified as one of the causes of B.d. spread, involving hundreds of species world wide. In this work we detected the presence of B.d. through histological examination on 5 out of 9 analyzed specimens of bullfrogs (Lithobates catesbeianus from a farm in Santa Fe City (Argentina, deposited since 1993 in the herpetological collection of the Provincial Museum of Natural Sciences "Florentino Ameghino". Our finding represents the oldest record of B.d. for Argentina and the first case of the chytrid fungus infecting the exotic bullfrog in this country. We emphasize the importance of determining and monitoring the distribution and spread of B.d in Argentina, particularly in areas where feral bullfrog populations have already been identified.La quitridiomicosis, enfermedad emergente producida por el hongo Batrachochytrium dendrobatidis (B.d., es reconocida como uno de los factores causantes de la declinación de anfibios. El comercio mundial de anfibios ha sido señalado como una de las fuentes de dispersión de B.d. En este trabajo se detectó la presencia de B.d. en la especie exótica rana toro (Lithobates catesbeianus mediante cortes histológicos en 5 de 9 ejemplares provenientes de un criadero de la ciudad de Santa Fe (Argentina, depositados y conservados desde 1993 en la Colección Herpetológica del Museo Provincial de Ciencias Naturales "Florentino Ameghino". Este registro representa el hallazgo más antiguo de B.d. en Argentina y el primer caso de este hongo en la rana toro exótica en el país; por lo que enfatizamos la importancia de determinar y monitorear la distribución y dispersión de B.d., particularmente en los sitios donde ya se han detectado poblaciones silvestres de rana toro.

  5. Hair cell recovery in mitotically blocked cultures of the bullfrog saccule

    OpenAIRE

    Baird, Richard A.; Burton, Miriam D.; Fashena, David S.; Naeger, Rebecca A.

    2000-01-01

    Hair cells in many nonmammalian vertebrates are regenerated by the mitotic division of supporting cell progenitors and the differentiation of the resulting progeny into new hair cells and supporting cells. Recent studies have shown that nonmitotic hair cell recovery after aminoglycoside-induced damage can also occur in the vestibular organs. Using hair cell and supporting cell immunocytochemical markers, we have used confocal and electron microscopy to examine the fate...

  6. Development of a water recirculating system for bullfrog production: technological innovation for small farmers

    Directory of Open Access Journals (Sweden)

    Sílvia Conceição Reis Pereira Mello

    2016-02-01

    Full Text Available ABSTRACT Despite the technological progress in frog farming, issues related to the environment, biosafety, and the use of technologies that minimise environmental impacts are frequently neglected by farmers. With the goal of developing a low-cost technology for reuse and preservation of water quality, an anaerobic filtering system combined with an aerobic filtering system was implemented in the grow-out sector in the Frog Culture Research Unit at Fundação Instituto de Pesca do Estado do Rio de Janeiro (FIPERJ. The filtering system received the effluent from six pens of frogs that were populated with 362 frogs in different development phases. The efficiency of the filtering system was evaluated by an analysis of the water before and after passing through the filters. In addition to the standards of water quality, the animals' performance was also observed through monitoring rates of survival, weight gain and feed conversion ratio. The results showed the effectiveness of the filtering system by removing organic matter, on average 87%. The values of total ammonia and non-ionisable reached 1.04 and 0.004 mg/L, respectively. Also, frogs subjected to the system presented satisfactory rates of weight gain and a high survival rate (97%.

  7. Toxicity of Euphorbia milii latex and niclosamide to snails and nontarget aquatic species.

    Science.gov (United States)

    Oliveira-Filho, E C; Paumgartten, F J

    2000-07-01

    The toxicity of Euphorbia milii molluscicidal latex and niclosamide (NCL) to target snails (Biomphalaria glabrata and Biomphalaria tenagophila) and nontarget aquatic organisms is evaluated. Planorbidae snails were killed by very low concentrations of lyophilized latex (48-h LC(50), mg/L: B. glabrata, 0.12; B. tenagophila, 0.09; Helisoma duryi, 0.10). Latex was less toxic (48-h LC(50) or EC(50), mg/L) to oligochaeta (Tubifex tubifex, 0.31), planktonic crustacea (Daphnia similis, 0.38; C. dubia, 1.07; Artemia sp., 0.93), and fishes (Danio rerio, 0.96; Poecilia reticulata, 1. 39), and considerably less toxic to Ampullariidae snails (Pomacea sp. , 10.55) and frog tadpoles (Rana catesbeiana, 7.50). Latex (up to 100 mg/L) was not toxic to bacteria (P. putida and V. fischeri), algae (Selenastrum capricornutum and Chlorella vulgaris), and mosquito larvae (Anopheles albitarsis, Aedes aegypti, Aedes fluviatilis). NCL was very toxic (48-h LC(50) or EC(50), mg/L) to Planorbidae snails (B. glabrata, 0.15, B. tenagophila, 0.13; H. duryi, 0.10), T. tubifex (0.11), crustacea (D. similis, 0.19; Ceriodaphnia dubia, 0.47; Artemia sp. 0.18), fishes (D. rerio, 0.25; P. reticulata, 0.29), R. catesbeiana (0.16), and Pomacea sp. (0.76). NCL was toxic to bacteria, algae (96-h IC(50), mg/L: S. capricornutum, 0.34; C. vulgaris, 1.23) and slightly toxic to mosquito larvae. In conclusion, E. milii latex, as compared with the reference molluscicide niclosamide, presents a higher degree of selectivity toward snails which are intermediate hosts of Schistosoma trematodes. PMID:10903832

  8. Prevalence of malformed frogs in Kaoping and Tungkang river basins of southern Taiwan.

    Science.gov (United States)

    Huang, Da-Ji; Chiu, Yuh-Wen; Chen, Chien-Min; Huang, Kai-Hsiang; Wang, Shu-Yin

    2010-05-01

    In this study we found many amphibians with bizarre appearances, known as malformations in Pingtung County southern Taiwan. For this investigation we collected frogs inhabiting the Kaoping and Tungkang river watersheds between February 2006 and June 2007. Among the total number of 10,909 normal frogs (i.e., anurans) collected during the investigation period, the Indian rice frogs (Rana limnocharis) account for the greatest number next is the Chinese bullfrog (Rana rugulosa). Of all the 244 captured malformed frogs, the Indian rice frog account for the greatest proportion. These malformed frogs have their main distribution in upstream areas of these two rivers. Our result indicates that the appearance rate of malformed frogs is 1.8% in the upstream reaches of the Kaoping River and 2.6%, and 0.8%, respectively in the upstream and midstream reaches of the Tungkang river. The most-commonly-found malformation is the lack of palms, followed by the lack of appendages, exostosis, and a malformed appendicular. It is, therefore, reasonable to speculate that the causes for the malformation may be related to the increased organic pollutants and agricultural chemicals used in the upstream reaches of these two rivers. PMID:21047008

  9. Морфофизиологические особенности строения тимуса озерной лягушки (Rana Ridibunda) и прыткой ящерицы (Lacerta agilis)

    OpenAIRE

    Грушко, М.

    2009-01-01

    В статье приведены результаты изучения центрального органа кроветворения тимуса озерной лягушки (Rana Ridibunda) и прыткой ящерицы (Lacerta agilis). Определены основные морфофизиологические особенности этого органа у представителей разных классов животных. Дана подробная характеристика качественного и количественного состава образующихся клеток крови в этом органе у лягушек и ящериц....

  10. Absence of invasive Chytrid fungus (Batrachochytrium dendrobatidis in native Fijian ground frog (Platymantis vitiana populations on Viwa-Tailevu, Fiji Islands

    Directory of Open Access Journals (Sweden)

    Edward Narayan

    2011-12-01

    Full Text Available We report on the first survey of chytridiomycosis (Batrachochytrium dendrobatidis- Bd in the endangered Fijian ground frog (Platymantis vitiana population on Viwa-Tailevu, Fiji Islands. This fungal pathogen has been implicated as the primary cause of amphibian declines worldwide. Few cases have been reported from tropical Asia however it was recently documented in 4 species of frogs in Indonesia. Two hundred individual frogs were swabbed from 5 different sites on Viwa Island. Swabs were tested to quantify the number of Bd zoospore equivalents using real-time Polymerase Chain Reaction (qPCR technique. We found zero (% prevalence of Bd in ground frogs. The lack of Bd may be due to 1 hot weather all year round inhibiting the spread of Bd, 2 Bd may be absent from Viwa Island due to a lack of amphibian introductions (not introduced or importation of exotic frogs such as Rana catesbeia-na, or Xenopus spp or pet trade spp or 3 the lack of introduction by human vectors due to the geographic isolation, and low visitation of non-local people into the island. While it is difficult to test these hypotheses, a precautionary approach would suggest an effective quarantine is required to protect Fiji’s endemic frogs from future disease outbreak. Conservation effort and research is needed at international level to assist the Fiji government in monitoring and protecting their unique endemic amphibians from outbreaks of B. dendrobatidis.

  11. Neural regulation of duodenal alkali secretion: Effects of electrical field stimulation

    International Nuclear Information System (INIS)

    The role of transmitters released from enteric neurons in regulating bicarbonate secretion by the proximal duodenum has been studied using electrical field stimulation (EFS). Stripped duodenal mucosa from Rana catesbeiana was mounted as an intact tube over circular platinum electrode,s and luminal alkalinization was measured by pH stat titration before, during, and after EFS. Transmucosal potential difference (PD) was simultaneously measured before and after EFS by paired electrodes. Square-wave pulses 50 V, 2 ms in duration, at 10 Hz were delivered in trains of 0.5 s at 1 Hz for periods of 15 min after stable basal secretion. This resulted in a 63 ± 27% increase in alkalinization that returned to basal values after cessation of the stimulus, without change in transmucosal PD. Serosal-to-lumen [3H]mannitol flux was not affected. Repetition of the stimulus resulted in a similar responses for as long as the tissue remained viable. The response to EFS was abolished by tetrodotoxin and veratrine indicating that intrinsic neurons were responsible for mediating the effect. In addition, the effect was blocked by serosal dinitrophenol, indicating that the secretory response occurred by a metabolically dependent process. These results indicate that alkalinization by proximal duodenum may be controlled by neurotransmitter release from local enteric neurons

  12. Genetic and biochemical effects induced by iron ore, Fe and Mn exposure in tadpoles of the bullfrog Lithobates catesbeianus.

    Science.gov (United States)

    Veronez, Alexandra Caroline da Silva; Salla, Rômulo Victor; Baroni, Vinícius Dadalto; Barcarolli, Indianara Fernanda; Bianchini, Adalto; Dos Reis Martinez, Claudia Bueno; Chippari-Gomes, Adriana Regina

    2016-05-01

    For decades, the extraction of minerals has intensified in order to meet the demand of industry. Iron ore deposits are important sources of metals, such as iron (Fe) and manganese (Mn). The particulate ores can be dispersed during extraction, transport and storage, with potential to induce biological impacts. Amphibians are very sensitive to environmental stressors. Therefore, the present study aimed to assess the effects of iron ore, Fe and Mn exposure during the metamorphosis of Lithobates catesbeianus. Endpoints analyzed included morphological (biometrical and developmental analyses), whole body Fe and Mn concentration in, plasma ferritin concentration, erythrocyte DNA damage (measured through comet assay and micronucleus test) and liver activity of enzymes involved in oxidative status [glutathione S-transferase (GST) and catalase (CAT)]. Tadpoles were kept under control condition (no contaminant addition) or exposed to iron ore (3.79mg/L as fine particulate matter); Fe (nominal concentration: 0.51mg/L Fe as C10H12FeN2NaO8; Fe-EDTA); and Mn (nominal concentration: 5.23mg/L Mn as 4H2O.MnCl2) for 30 days. Virtually, no mortality was observed, except for one tadpole found dead in the iron ore treatment. However, tadpoles exposed to iron ore had longer tail than those kept under control conditions while tadpoles exposed to manganese chloride showed higher body length than control ones. Exposure to Fe and Mn induced a delay in tadpole metamorphosis, especially when these metals are presented not as a mixture (iron ore). Tadpoles exposed to iron ore had increased whole body Fe and Mn while those exposed to Fe and Mn accumulated each metal individually. Tadpoles exposed to any of the contaminants tested showed a significant increase in erythrocyte DNA damage and frequency of micronuclei. In addition, they showed higher liver GST activity respect with those kept under control conditions. Plasma ferritin concentration and liver CAT activity were higher only in tadpoles exposed to iron ore. These findings indicated that tadpoles accumulated Fe and Mn at the whole body level after exposure to the single metals or to their mixture as iron ore. In addition, they indicate that Fe and Mn accumulation can induce oxidative stress with consequent significant developmental, genotoxic and biochemical effects in L. catesbeianus tadpoles. PMID:26930479

  13. Profile of cortisol, glycaemia, and blood parameters of American Bullfrog tadpoles Lithobates catesbeianus exposed to density and hypoxia stressors

    Directory of Open Access Journals (Sweden)

    Patricia C. Teixeira

    2012-12-01

    Full Text Available The aim of this study was to evaluate alterations to the physiological profile (cortisol, glycaemia, and blood parameters of Lithobates catesbeianus caused by the stressors density and hypoxia. The organisms were in the prometamorphosis stage and exposed to different tadpole densities: 1 tadpole/L (T1, 5 tadpoles/L (T2, and 10 tadpoles/L (T3 for 12 days. The blood was collected through the rupture of the caudal blood vessel and collected under normoxia (immediate collection and hypoxia (after 15 minutes of air exposure conditions. Cortisol levels rose on the fourth and eighth days of treatment and returned to basal levels by the end of the experiment. The stressor mechanisms tested did not affect glycaemia. White blood cells (total number of lymphocytes, neutrophils, and eosinophils showed a significant difference at the twelfth day of the experiment when compared with the start of the experiment. We concluded that, under controlled conditions, a density of up to 10 tadpoles/L and air exposure for 15 minutes did not cause harmful physiological alterations during the experimental period. The answer to these stressors maybe was in another hormonal level (corticosterone.

  14. Rana prognoza kvaliteta života politraumatizovanih bolesnika sa prelomima dugih kostiju

    OpenAIRE

    Gvozdenović, Nemanja

    2016-01-01

    Pod pojmom politraume se podrazumeva teška istovremena povreda najmanje dve regije tela sa anatomskom težinom povrede AIS koja je jednaka ili veća od tri kao i ukupna izračunata anatomska težina povreda izražena ISS zbirom mora da bude veća od 15. Cilj istraživanja je da se primenom upitnika (SF36, PTSD–testa i Glazgov skale ishoda) proceni kvalitet života između politraumatizovanih pacijenata sa prelomomima dugih kostiju i politraumatizovanih bez preloma duge kosti kao i da se u...

  15. Representation of the visual field in the anterior thalamus of the leopard frog, Rana pipiens.

    Science.gov (United States)

    Skorina, Laura K; Recktenwald, Eric W; Dudkin, Elizabeth A; Saidel, William M; Gruberg, Edward R

    2016-05-16

    We used physiological and anatomical methods to elucidate how the visual field is represented in the part of the dorsal anterior thalamus of the leopard frog that receives direct retinal projections. We recorded extracellularly while presenting visual stimuli, and characterized a physiologically defined region that encompasses the retinal projections as well as an extended zone beyond them. We probed the area systematically to determine if the zone is organized in a visuotopic map: we found that it is not. We found that units in this region respond only to stimuli in the contralateral half of the visual field, which is similar to what is seen in the dorsal lateral geniculate nucleus in mammals. When we backfilled retinal ganglion cells from application of HRP to the anterior thalamus, we found labeled cells only in those parts of the retina corresponding to the contralateral hemifield, confirming our physiological observations. PMID:27064110

  16. Ranas y sapos del fondo de tu casa : Anfibios de agroecosistemas de La Plata y alrededores

    OpenAIRE

    Agostini, María Gabriela

    2012-01-01

    La palabra anfibio hace referencia a cualquier objeto que pueda usarse tanto en un medio terrestre como en uno acuático. Por ejemplo, existen autos a los cuales se los llama anfibios. Pero esta palabra también se utiliza para referirse a un grupo de animales vertebrados que tienen la característica de pasar parte de su vida como renacuajos acuáticos y que, en su edad adulta, ocupan generalmente ambientes terrestres (aunque siempre permanecen relacionados a sitios con humedad). Esta caracterís...

  17. Rana stimulacija mozga i kognitivne sposobnosti djece predškolske dobi Marte Meo

    OpenAIRE

    Rumenjak, Petra

    2013-01-01

    Metoda Marte Meo se sve više prihvaća kao učinkovit program poticanja razvoja primjenjiv u svakodnevnim interakcijama te je prihvaćena kao djelotvorna metoda za prirodno poticanje komunikacije osoba koje imaju teškoća u ostvarivanju kvalitetnih interakcija s drugima. O metodi Marte Meo piše edukacijska rehabilitatorica Petra Rumenjak.

  18. Trait Performance Correlations across Life Stages under Environmental Stress Conditions in the Common Frog, Rana temporaria

    OpenAIRE

    Johansson, Frank; Lederer, Baptiste; Lind, Martin I.

    2010-01-01

    If an organism's juvenile and adult life stages inhabit different environments, certain traits may need to be independently adapted to each environment. In many organisms, a move to a different environment during ontogeny is accompanied by metamorphosis. In such organisms phenotypic induction early in ontogeny can affect later phenotypes. In laboratory experiments we first investigated correlations between body morphology and the locomotor performance traits expressed in different life stages...

  19. 203Hg binding in the liver and kidney of the frog, Rana tigrina

    International Nuclear Information System (INIS)

    Following a single i.p. dose of the radioisotope, 203Hg was found to accumulate in both the high and low molecular weight (MW) fractions of the kidney and liver of the frog. The course of 203Hg appearance in the 2 fractions varied in the liver; 203Hg was exclusively associated with the higher MW fractions at 2 days whereas the radiotracer appeared in both low and high MW fractions at 4 and 7 days after administration. In the kidneys, however, 203Hg was associated with high and low MW fractions at all the intervals studied. Low MW 203Hg binding fraction appeared to be a metallothionein-like substance. (Auth.)

  20. Effects of X-irradiation on some aspects of protein metabolism in the frog, Rana hexadactyla

    International Nuclear Information System (INIS)

    Changes in the level of total proteins and protease in brain, muscle and liver tissues of normal and X-irradiated frogs were determined. Low doses of radiation produced an increment in protein level while high doses produced decrement. However, protease activity at all doses exhibited an elevatory trend. Exposure of frogs to lethal doses resulted in increased protease activity and decreased protein content during post-irradiation periods. The results are discussed on the basis of protein destruction and lysosomal damage. (auth.)

  1. Effects of X-irradiation on acetyl cholinesterase activity in the frog Rana hexadactyla

    International Nuclear Information System (INIS)

    Changes in acetylchloinesterase (AChE) activity in brain, muscle and liver tissues of normal and X-irradiated frogs were studied. Low doses of radiation produced an increase in enzyme activity while high doses produced decrement. Post-irradiation studies with sublethal dose showed an early increase followed by reversible decrement in enzyme activity while lethal dose exhibited an early increase followed by irreversible inhibition of enzyme activity. (author)

  2. Effects of oil sands waste water on the wood frog (rana sylvatica)

    International Nuclear Information System (INIS)

    The sustainability of various reclamation strategies can be determined by the growth and health of indigenous amphibians (Wood Frogs). This paper referred to the large quantities of tailings water that are generated by oil sand extraction activities. It presented the results of a study that was conducted in the spring and summer of 2006 and 2007 on reclaimed formation wetlands comprising tailings water. The objective was to understand the impact of these wetlands on native amphibians. Frogs were exposed to wetlands containing oil sands process affected water (OSPW) and reference water (no OSPW). Six experimental trenches were made at one site in the first year. Each trench had 3 enclosures with 50 tadpoles. In the second year, there were 13 sites, including 6 reference and 7 OSPW affected sites, which were classified as old (more than 8 yrs) or young (less than 7 yrs). Four enclosures, with 50 tadpoles each, were placed in each wetland. The study involved the evaluation of growth rate, survival, time to metamorphosis, thyroid hormone concentrations, liver EROD activity, and tissue retinol concentrations. In addition, stable isotopes were used to track carbon flow from primary production plants, through the food chain, to tadpoles and frogs which represent intermediate and higher trophic levels in reclaimed wetlands

  3. Effects of road de-icing salt (NaCl) on larval wood frogs (Rana sylvatica)

    International Nuclear Information System (INIS)

    Vast networks of roads cover the earth and have numerous environmental effects including pollution. A major component of road runoff in northern countries is salt (mostly NaCl) used as a winter de-icing agent, but few studies of effects of road salts on aquatic organisms exist. Amphibians require aquatic habitats and chemical pollution is implicated as a major factor in global population declines. We exposed wood frog tadpoles to NaCl. Tests revealed 96-h LC50 values of 2636 and 5109 mg/l and tadpoles experienced reduced activity, weight, and displayed physical abnormalities. A 90 d chronic experiment revealed significantly lower survivorship, decreased time to metamorphosis, reduced weight and activity, and increased physical abnormalities with increasing salt concentration (0.00, 0.39, 77.50, 1030.00 mg/l). Road salts had toxic effects on larvae at environmentally realistic concentrations with potentially far-ranging ecological impacts. More studies on the effects of road salts are warranted. - Road salts have toxic effects on amphibians at environmentally realistic concentrations

  4. Histology of the mucosa of the oesophagogastric junction and the stomach in adult Rana perezi.

    OpenAIRE

    Gallego-Huidobro, J; Pastor, L M

    1996-01-01

    The histological structure of the frog digestive mucosa changes at the oesophagogastric junction. The pseudostratified ciliated mucosal epithelium of oesophageal type changes to a simple mucus-secreting epithelium of gastric type. The glands straighten and the muscularis mucosae develops as a complete layer. The muscularis increases in thickness. Unlike the mammalian stomach, in the frog the surface of the plicae forms convoluted ridges that delimit furrow-shaped pits. Two types of gastric gl...

  5. Nueva especie de rana (atelopus) de los farallones de cali, cordillera occidental de colombia

    OpenAIRE

    Kattan, Gustavo

    2012-01-01

    Durante la realización de colecciones herpetológicas en el Departamento del Valle del Cauca, fue encontrada una especie no descrita de Atelopus (Anura: Bufonidae) en los farallones de Cali, a 2600 m de altura. Esta es la primera especie en este género que se encuentra a elevaciones superiores a 2000 m en la Cordillera Occidental. Se conocen varias especies de Atelopus en las Cordilleras Central y Oriental de Colombia y en los Andes ecuatorianos (COCHRAN y GOIN 1970; PETERS 1973; RIVERO 1963) ...

  6. Modelling the impact of roads on regional population of Moor frogs (Rana arvalis)

    DEFF Research Database (Denmark)

    Pontoppidan, Maj-Britt

    ecologically sustainable road planning conservation measures must be taken into consideration already in the earliest phases of road development. This requires adequate tools for assessment, prevention and mitigation of the impacts of infrastructure. For this reason the Danish Road Directorate decided to...... have to be constructed and analysed. The first scenario should be a map of the area as it is before the planned road construction (scenario 0). This analysis measures the ecological performance of the original landscape and is a reference against which other scenarios are to be compared. The second map...... (scenario 1) should show the landscape as it is expected to be after the road constructions. In combination, the analyses of scenario 0 and scenario 1 make it possible to assess the effect of road construction on connectivity and population persistence. The analyses also constitute the basis for planning of...

  7. Basic response characteristics of auditory nerve fibers in the grassfrog (Rana temporaria)

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Jørgensen, M B; Kanneworff, M

    phasic cells giving one spike per stimulation. Therefore, the mechanism underlying PS is probably different from that underlying adaptation. The sharpening of the neural encoding of temporal parameters and the strong encoding of sound offset as well as onset caused by PS very likely is biologically...

  8. Spatio-temporal Dynamics of Pond Use and Recruitment in Florida Gopher Frogs (Rana Capito aesopus)

    Energy Technology Data Exchange (ETDEWEB)

    Greenberg, C.H.

    2000-05-16

    We examined spatio-temporal dynamics of the Florida Gopher frog breeding and juvenile recruitment. Ponds were situated in a hardwood or pine-savanna matrix of upland forest. Movement was monitored from 1994-1999. Adult pond use was low but relatively constant. Juvenile recruitment was higher in the upland savanna matrix. Body size was negatively correlated with the number of juveniles exiting the pond in only one year suggesting intraspecific competition is one of many factors. Most immigration occurred in May through August and was unrelated to rainfall.

  9. Extinction of montane populations of the northern leopard frog (Rana pippins) in Colorado

    Science.gov (United States)

    Corn, Paul Stephen; Fogleman, James C.

    1984-01-01

    Between 1973 and 1982 nine populations of the northern leopard frog in the Red Feather Lakes region of Larimer County, Colorado, failed in reproduce. These failures all resulted in extinction of the populations. One area formerly supporting a population was recolonized in 1980, but no frogs were observed at any of the nine sites in 1981 or 1982. Six of the populations went extinct because the breeding ponds dried up. The remaining populations were small enough to be susceptible to random events, but the nature of these events is unknown.

  10. Virulence properties of motile aeromonads isolated from farmed frogs Rana tigerina and R. rugulosa.

    Science.gov (United States)

    Pearson, M D; Hirono, I; Aoki, T; Miranda, R; Inglis, V

    2000-04-20

    Virulence factors were compared in Aeromonas species isolated from clinically normal and septicaemic farmed frogs from Thailand. Haemolysin activities against frog erythrocytes were significantly different within the collection of aeromonads. Groups of high haemolytic activity (unspeciated Aeromonas, Au), moderate haemolytic activity (A. hydrophila), and low haemolytic activity (A. veronii biovar sobria, A. veronii biovar veronii, A. caviae, A. schubertii) were noted. DNA colony hybridisation studies revealed that Au isolates possessed a haemolysin gene (ASH1) which was not present in any of the other Thai aeromonads or type strains tested. Elastinolytic activity was demonstrated in 90% of the Au isolates, 60% of the A. hydrophila isolates and in none of the other motile aeromonads. The cytotoxic activity of the Aeromonas isolates varied according to the source of cells used in the assays. Cells from rainbow trout were extremely sensitive to Au toxins but less so to toxins produced by other species. In contrast mammalian cells showed very little sensitivity to Au toxins but were more sensitive to toxins produced by A. hydrophila. Selection of suitable assay substrates is therefore important. PMID:10843556

  11. Trichobothrial mediation of an aquatic escape response: Directional jumps by the fishing spider, Dolomedes triton, foil frog attacks

    Directory of Open Access Journals (Sweden)

    Robert B. Suter

    2003-07-01

    Full Text Available Fishing spiders (Pisauridae frequent the surfaces of ponds and streams and thereby expose themselves to predation by a variety of aquatic and semi-aquatic vertebrates. To assess the possibility that the impressive jumps of fishing spiders from the water surface function in evading attacks by frogs, attacks by bullfrogs (Rana catesbiana and green frogs (R. clamitans on Dolomedes triton were studied. Both the attack dynamics of the frogs and the evasive behaviors of the spiders were recorded at 250 frames per second. A freeze-dried bullfrog, propelled toward spiders with acceleration, posture, and position that approximated the natural attack posture and dynamics, was used to assess the spiders' behavior. Qualitatively, the spiders responded to these mock-attacks just as they had to attacks by live frogs: jumping (N=29 jumps, 56.9% of instances, rearing the legs nearest the attacking frog (N=15, 29.4%, or showing no visible response (N=7, 13.7%. Spiders that jumped always did so away (in the vertical plane from the attack (mean =137° vs. vertical at 90° or horizontally toward the frog at 0°. The involvement of the trichobothria (leg hairs sensitive to air movements, and the eyes as sensory mediators of the evasion response was assessed. Spiders with deactivated trichobothria were significantly impaired relative to intact and sham-deactivated spiders, and relative to spiders in total darkness. Thus, functional trichobothria, unlike the eyes, are both necessary and sufficient mediators of the evasion response. Measurements of air flow during frog attacks suggest that an exponential rise in flow velocity is the airborne signature of an attack.

  12. First survey for the amphibian chytrid fungus Batrachochytrium dendrobatidis in Connecticut (USA) finds widespread prevalence.

    Science.gov (United States)

    Richards-Hrdlicka, Kathryn L; Richardson, Jonathan L; Mohabir, Leon

    2013-02-28

    The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) is an emerging infectious fungal pathogen of amphibians and is linked to global population declines. Until now, there has only been 1 survey for the fungus in the northeastern USA, which focused primarily on northern New England. We tested for Bd in a large number of samples (916 individuals from 116 sites) collected throughout the state of Connecticut, representing 18 native amphibian species. In addition, 239 preserved wood frog Lithobates sylvaticus tadpoles from throughout the state were screened for the fungus. Bd presence was assessed in both the fresh field swabs and the preserved samples using a sensitive quantitative PCR assay. Our contemporary survey found widespread Bd prevalence throughout Connecticut, occurring in 14 species and in 28% of all sampled animals. No preserved L. sylvaticus specimens tested positive for the fungus. Two common species, bullfrogs R. catesbeiana and green frogs R. clamitans had particularly high infection rates (0.21-0.39 and 0.33-0.42, respectively), and given their wide distribution throughout the state, we suggest they may serve as sentinels for Bd occurrence in this region. Further analyses found that several other factors increase the likelihood of infection, including life stage, host sex, and host family. Within sites, ponds with ranids, especially green frogs, increased the likelihood of Bd prevalence. By studying Bd in populations not facing mass declines, the results from this study are an important contribution to our understanding of how some amphibian species and populations remain infected yet exhibit no signs of chytridiomycosis even when Bd is widely distributed. PMID:23446966

  13. Effect of static magnetic fields on the metamorphosis of frogs; Kaeru no hentai katei ni oyobosu jiba no eikyo ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Hiwaki, O. [Hiroshima City University, Hiroshima (Japan)

    1996-01-20

    The effect of static magnetic fields on the metamorphosis of frogs was investigated to examine the effect of static magnetic fields on the internal secretion system and nerve system in a living body. In this experiment, the growth and metamorphosis of a Rana Japonica`s larva are inhibited inside the vessel in which a magnet whose upper surface is the N pole was put at the bottom. However, no remarkable change was recognized when a magnet whose upper surface is the S pole was put at the bottom. For a bullfrog, the same result as described above was obtained. The experiment result shows that the vertical upward fields inhibit the growth and metamorphosis of a frog`s larva, but the vertical downward fields do not remarkably act on them. As a result of this experiment, the growth and metamorphosis of a frog are considered to act on the internal secretion system of a tadpole in static magnetic fields when the control by thyroxin is considered. Since the existence of action varies depending on the polarity of vertical magnetic fields, the magnet in a living body is judged to be associated with the internal secretion system of a tadpole. 17 refs., 8 figs.

  14. Diets of three species of anurans from the cache creek watershed, California, USA

    Science.gov (United States)

    Hothem, R.L.; Meckstroth, A.M.; Wegner, K.E.; Jennings, M.R.; Crayon, J.J.

    2009-01-01

    We evaluated the diets of three sympatric anuran species, the native Northern Pacific Treefrog, Pseudacris regilla, and Foothill Yellow-Legged Frog, Rana boylii, and the introduced American Bullfrog, Lithobates catesbeianus, based on stomach contents of frogs collected at 36 sites in 1997 and 1998. This investigation was part of a study of mercury bioaccumulation in the biota of the Cache Creek Watershed in north-central California, an area affected by mercury contamination from natural sources and abandoned mercury mines. We collected R. boylii at 22 sites, L. catesbeianus at 21 sites, and P. regilla at 13 sites. We collected both L. catesbeianus and R. boylii at nine sites and all three species at five sites. Pseudacris regilla had the least aquatic diet (100% of the samples had terrestrial prey vs. 5% with aquatic prey), followed by R. boylii (98% terrestrial, 28% aquatic), and L. catesbeianus, which had similar percentages of terrestrial (81%) and aquatic prey (74%). Observed predation by L. catesbeianus on R. boylii may indicate that interaction between these two species is significant. Based on their widespread abundance and their preference for aquatic foods, we suggest that, where present, L. catesbeianus should be the species of choice for all lethal biomonitoring of mercury in amphibians. Copyright ?? 2009 Society for the Study of Amphibians and Reptiles.

  15. Phylogeny, ecological fitting and lung flukes: helping solve the problem of emerging infectious diseases Filogenia, flexibilidad ecológica y digéneos de pulmones: ayudando a resolver la crisis de las enfermedaes infecciosas emergentes

    Directory of Open Access Journals (Sweden)

    Daniel R. Brooks

    2006-12-01

    Full Text Available Traditional wisdom, based on assumptions of species-specific coevolutionary interactions between hosts and parasites, suggests that pathogens with multi-host life cycles are unlikely to move with their definitive hosts because their transmission requirements are so specialized. Ecological fitting provides a theory of diffuse coevolution, which allows introduced pathogens with complex life cycles to become established and spread rapidly into native hosts if the resource required at each stage of the life cycle is both phylogenetically conservative (distributed among numerous species and geographically widespread. The external appearance of life cycle complexity does not, therefore, on its own, predict the potential for an organism to become an emerging infectious disease. We apply this concept to explain a potential enigma, the presence of a lung fluke, Haematoloechus floedae, endemic to North American bullfrogs, in Costa Rican leopard frogs, even though there are no bullfrogs extant in the country today, and none ever occurred where the parasite has been discovered. We then discuss how the integration of ecological and life history information within a phylogenetic framework can help biologists move from attempts to manage emerging infectious disease outbreaks to the ability to predict and thus circumvent the outbreak in the first place.Con base en el supuesto de coevolución a nivel de especies de parásitos y hospederos, tradicionalmente se asume como poco probable que aquellos patógenos con ciclos de vida que involucran varios hospederos acompañen a su hospedero definitivo a un nuevo ambiente, por lo especializado de sus requerimientos de transmisión. El fenómeno de flexibilidad ecológica aporta una teoría de coevolución difusa, que permite a los patógenos con ciclos de vida complejos, que han sido introducidos, establecerse y dispersarse de una manera rápida en hospederos nativos, si el recurso requerido en cada etapa del ciclo de

  16. Light-dependent magnetic compass in Iberian green frog tadpoles

    Science.gov (United States)

    Diego-Rasilla, Francisco Javier; Luengo, Rosa Milagros; Phillips, John B.

    2010-12-01

    Here, we provide evidence for a wavelength-dependent effect of light on magnetic compass orientation in Pelophylax perezi (order Anura), similar to that observed in Rana catesbeiana (order Anura) and Notophthalmus viridescens (order Urodela), and confirm for the first time in an anuran amphibian that a 90° shift in the direction of magnetic compass orientation under long-wavelength light (≥500 nm) is due to a direct effect of light on the underlying magnetoreception mechanism. Although magnetic compass orientation in other animals (e.g., birds and some insects) has been shown to be influenced by the wavelength and/or intensity of light, these two amphibian orders are the only taxa for which there is direct evidence that the magnetic compass is light-dependent. The remarkable similarities in the light-dependent magnetic compasses of anurans and urodeles, which have evolved as separate clades for at least 250 million years, suggest that the light-dependent magnetoreception mechanism is likely to have evolved in the common ancestor of the Lissamphibia (Early Permian, ~294 million years) and, possibly, much earlier. Also, we discuss a number of similarities between the functional properties of the light-dependent magnetic compass in amphibians and blue light-dependent responses to magnetic stimuli in Drosophila melanogaster, which suggest that the wavelength-dependent 90° shift in amphibians may be due to light activation of different redox forms of a cryptochrome photopigment. Finally, we relate these findings to earlier studies showing that the pineal organ of newts is the site of the light-dependent magnetic compass and recent neurophysiological evidence showing magnetic field sensitivity in the frog frontal organ (an outgrowth of the pineal).

  17. Rethinking the biological relationships of the thyroid hormones, l-thyroxine and 3,5,3'-triiodothyronine.

    Science.gov (United States)

    Maher, Stacey K; Wojnarowicz, Pola; Ichu, Taka-Aki; Veldhoen, Nik; Lu, Linghong; Lesperance, Mary; Propper, Catherine R; Helbing, Caren C

    2016-06-01

    Thyroid hormones (THs), l-thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are essential for vertebrate growth and development. Classically, T4 is 5'-deiodinated to the active hormone, T3, in target tissues which then binds nuclear TH receptors (TRs) and regulates gene transcription. However, it is possible that T4 acts directly on target tissues. Frog metamorphosis is a powerful TR-dependent model for studying TH action. Premetamorphic Rana (Lithobates) catesbeiana tadpoles were injected with 0.1-50 T3 or 0.5-250T4pmol/gbodyweight to account for their 5-fold difference in biological activity and the mRNA profiles in six tissues from well-characterized TH-responsive genes were evaluated after 48h using quantitative real time polymerase chain reaction. 5'-deiodinase-poor tissues should produce superimposable dose-response curves if T4 does not require conversion to T3. This was the case in lung and tail fin; the latter tissue recapitulating these responses in organ culture. 5'-deiodinase-rich tissues should convert T4 to T3. Because T3 has a higher affinity to TRs, a 5-fold higher T4 dose compared to T3 should produce greater transcript induction. This was observed in the brain and for most intestinal transcripts. However, some gene transcripts in the intestine and all transcripts in the back skin produced superimposable response curves suggesting that a direct mode of T4 action is plausible in these tissues. While the liver showed results consistent with its 5'-deiodinase-poor status, we found evidence of an alternate, non-genomic mechanism for two gene transcripts. Therefore, mechanisms not requiring T4 conversion to T3 may play a far greater role than previously thought. PMID:27085304

  18. Quantification of 11 thyroid hormones and associated metabolites in blood using isotope-dilution liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Hansen, Martin; Luong, Xuan; Sedlak, David L; Helbing, Caren C; Hayes, Tyrone

    2016-08-01

    This paper describes a novel analytical methodology for the simultaneous determination of absolute and total concentrations of 11 native thyroid hormones and associated metabolites, viz. thyroxine (T4), 3,3', 5-triiodothyronine (T3), 3,3', 5'-triiodothyronine (rT3), 3,5-diiodothyronine (3,5-T2), 3,3'- diiodothyronine (3,3'-T2), 3-iodothyronine (T1), thyronine (T0), 3-iodothyronamine (T1AM), tetraiodothyroacetic acid (Tetrac), triiodothyroacetic acid (Triac), and diiodothyroacetic acid (Diac), in 50-μL of plasma or serum. The method was optimized using four isotopic labeled surrogate and internal standards in combination with solid-phase extraction and LC-MS/MS. The methodology was further evaluated using amphibian plasma and serum with matrix-matched calibration applied for quantification. Method detection limits are 3.5 pg T4, 1.5 pg T3, 2.9 pg rT3, 1.7 pg 3,3'-T2, 2.3 pg 3,5-T2, and between 0.3 and 7.5 pg for the remaining six metabolites in 50 μL aliquots of blood sera or plasma. Accuracies and repeatabilities for all analytes were between 88 and 103 % and 1.31 and 17.2 %, respectively. Finally, we applied the method on adult frog (Xenopus laevis) plasma and tadpole (Rana (Lithobates) catesbeiana) serum. We observed up to seven different thyroid hormones and associated metabolites in tadpole serum. This method will enable researchers to improve the assessment of thyroid homeostasis and endocrine disruption in animals and humans. Graphical Abstract Quantification of 11 thyroid hormones and metabolites from 50 μL plasma or serum using protein denaturation in combination with solid-phase extraction followed by LC-MS/MS. PMID:27215639

  19. Nanometals induce stress and alter thyroid hormone action in amphibia at or below North American water quality guidelines.

    Science.gov (United States)

    Hinther, Ashley; Vawda, Saadia; Skirrow, Rachel C; Veldhoen, Nik; Collins, Patricia; Cullen, Jay T; van Aggelen, Graham; Helbing, Caren C

    2010-11-01

    Nanometals are manufactured to particle sizes with diameters in the nanometer range and are included in a variety of consumer and health products. There is a lack of information regarding potential effects of these materials on aquatic organisms. Amphibians are regarded as environmental sentinels and demonstrate an exquisite sensitivity to thyroid hormone action, a hormone that is essential for human health. This present study assessed the effect of exposure to nanometals on stress and thyroid hormone signaling in frog tissue using a cultured tail fin biopsy (C-fin) assay derived from Rana catesbeiana tadpoles. The C-fin assay maintains tissue complexity and biological replication while multiple chemical responses can be assessed from the same individual. We tested the ability of nanosilver (0.06 μg/L-5.5 mg/L), quantum dots (0.25 μg/L-22 mg/L), and nanozinc oxide (0.19-10 mg/L) to alter gene expression in the presence or absence of 3,3',5'-triiodothyronine (T(3)) using quantitative real-time polymerase chain reaction. Results were compared to exposure to micrometer-silver, silver nitrate, and micrometer-cadmium telluride. Nanosilver (≥2.75 mg/L) and quantum dots (≥0.22 mg/L) altered the expression of transcripts linked to T(3)- and stress-mediated pathways, while nanozinc oxide had no effect. Lower concentrations of nanosilver (0.6 to 550 μg/L) perturbed T(3)-mediated signaling while not inducing cell stress. The observed effects were orders of magnitude below acute toxicity levels and occurred at or below the current North American water quality guidelines for metals, underscoring the need for evaluating nanoparticles separately from their constituent chemicals. PMID:20929207

  20. Comparison of the Early Embryonic Development Between Rana tigrina cantor and Rana tigrina rugulosa%泰国虎纹蛙与中国虎纹蛙早期胚胎发育比较研究

    Institute of Scientific and Technical Information of China (English)

    刘丽; 刘楚吾; 罗隆胜

    2008-01-01

    比较了泰国虎纹蛙与中国虎纹蛙在控温条件下的胚胎发育过程.结果表明:两亚种蛙在右鳃封闭期与鳃盖完成期之间有明显的"角质颌出现"的特征,因而在传统分期的基础上增加了一个"角质颌出现期",从而将两者自受精卵开始到鳃盖完成期为止划分为26个时期;两亚种蛙大部分发育时期外形特征基本相同,但八细胞期细胞的排列方式,两亚种蛙神经褶期的神经沟形状、纤毛出现期的神经褶棱高度等均不同;泰国虎纹蛙的发育速度较快,自受精卵期到鳃盖完成期共耗时70.4 h,中国虎纹蛙在相同的条件下则需92.5 h,但在四细胞期、八细胞期、神经管期和尾芽期,泰国虎纹蛙的发育速度却较中国虎纹蛙慢.

  1. 棘胸蛙、虎纹蛙、黑斑蛙血细胞的比较%Comparison of Blood Cells of Paa spinosa, Rana rugulosa and Rana nigromaculata

    Institute of Scientific and Technical Information of China (English)

    胡知渊; 来雅萍; 陈文静

    2005-01-01

    应用Giemsa染色法对棘胸蛙、虎纹蛙和黑斑蛙的血细胞进行显微观察和各形态参数测定,并对各类细胞作了图示和描述.结果表明,红细胞和白细胞的形态和数量比例有一定属和种的特征,并与其生长环境和进化地位有一定联系.

  2. In-situ caging of wood frog (Rana sylvatica) larvae in wetlands formed from oil sands tailings materials (OSPM)

    Energy Technology Data Exchange (ETDEWEB)

    Hersikorn, B.; Smits, J.E. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2009-07-01

    The reclamation of oil sand tailings through the formation of wetlands was examined during the spring and summer of 2006 and 2007 in a mesocosm study of indigenous amphibians (wood frogs). In both years, frogs were exposed to wetlands containing oil sands process-affected materials (OSPM) and reference wetlands that did not contain any OSPM. In year 2 there were 14 sites, of which 7 were reference sites and 7 were OSPM- affected sites. The sites were classified as older or younger than 7 yrs. Four enclosures, each containing 50 tadpoles, were placed in each wetland. Survival time to metamorphosis, and thyroid hormone ratios of larvae raised in young OSPM wetlands were found to be different from those of reference wetlands and old OSPM wetlands. This presentation also provided data on liver EROD activity and whole-body triglyceride concentrations. The study showed that the formation of wetlands from tailings material may support populations of amphibians if the wetlands are given the time to age. The development and health of native amphibians reflects the sustainability of the different reclamation strategies and delineates how higher trophic level organisms may be affected by OSPM.

  3. Correlation between chloride flux via the mitochondria-rich cells and transepithelial water movement in isolated frog skin (Rana esculenta).

    Science.gov (United States)

    Nielsen, R

    1995-12-01

    The coupling between net transepithelial Cl- influx and net water flow was investigated. Experiments were performed on isolated frog skin bathed in isotonic Cl- Ringer's solution in the presence of the Na+ channel blocking agent amiloride in the mucosal solution. The skins were voltage-clamped at -80 or -100 mV (with the serosal solution as reference). Under these conditions the current across the skin is carried by an influx of Cl-. In the absence of antidiuretic hormone the correlation between current and net water flow was low, but in the presence of the antidiuretic hormone, arginine vasotocin, there was a highly significant correlation between current and net water flow. The data presented here indicate that under steady state conditions about 70 molecules of water follow each Cl- ion across the skin. If the water influx is driven by electroosmosis one would expect that a change in current should result in an immediate change in the water flow. There was, however, a considerable time delay between the change in current and water flow. This indicates that the observed coupling between Cl- flux and water flow is caused by current-induced local osmosis and not electroosmosis. PMID:8719255

  4. Identification of parental chromosomes in hybridogenetic water frog Pelophylax esculentus (Rana esculenta) by genomic in situ hybridization (GISH)

    Czech Academy of Sciences Publication Activity Database

    Zalésna, A.; Choleva, Lukáš; Ogielska, M.; Rábová, Marie; Marec, František; Ráb, Petr

    2010-01-01

    Roč. 18, č. 16 (2010), s. 754-755. ISSN 0967-3849. [19th International Colloquium on animal cytogenetics and gene mapping. 06.06.-09.06.2010, Krakow] Institutional research plan: CEZ:AV0Z50450515; CEZ:AV0Z50070508 Keywords : parental chromosomes * Pelophylax esculentus * hybridization Subject RIV: EB - Genetics ; Molecular Biology

  5. Estimation of the factors determining body size of youngs of the year of Rana temporaria L. before a hibernation

    Directory of Open Access Journals (Sweden)

    Kutenkov Anatoly Petrovich

    2013-10-01

    This equation and statistical analysis showed that the year-to-year morphological variability of juvenile frogs by the autumn depends on air temperature, rainfall, and the time of exposition (from the beginning of metamorphosis up to the end of foraging, rather than intrinsic properties of different groups of newly metamorphosed froglets.

  6. Ecology of anuran populations inhabiting thermally stressed aquatic ecosystems, with emphasis on larval Rana pipiens and Bufo terrestris

    International Nuclear Information System (INIS)

    Field and laboratory studies were conducted to determine the responses of anuran populations to thermally stressed aquatic ecosystems. Adult and larval amphibians were sampled in and around a cool arm of a 67 ha reservoir that receives high temperature effluent from a nuclear production reactor on the Savannah River Plant (SRP) in South Carolina. Patterns for some species were compared with data from nearby unheated areas and analyzed in terms of the thermal gradient (16-45 C) extending the length of the reservoir's cool arm. The adaptation to breeding during nocturnal rainfall fortuitously confers a double advantage especially to anurans breeding in thermally stressed waters. (U.S.)

  7. COMPARISION OF POTENCY OF DIFFERENT TYPES NEURO-MUSCULAR JUNCTION (NMJ BLOCKERS ON ISOLATED RECTUS ABDOMINIS MUSCLE OF RANA TIGRINA

    Directory of Open Access Journals (Sweden)

    Sanghishetty Vijay Prasad

    2012-08-01

    Full Text Available The most important use of neuromuscular blockers is as adjuvant to general anaesthesia whereadequate muscle relaxation can be achieved at lighter plane. They also reduce reflex muscle contraction in the regionundergoing surgery and assist maintenance of controlled ventilation during anaesthesia. They are particularly helpfulin abdominal and thoracic surgery, intubations and endoscopies, orthopedic manipulation, etc. Thus, the risk ofrespiratory and cardiovascular depression is minimized, and post anesthetic recovery is shortened. The potency ratioof two commonly used neuromuscular agents depolarizing succinylcholine and non depolarizing pancuronium.Double pith a frog and fasten it to a frog board with ventral side up. The sternum was cut through just above thexiphisternum at its base and a pair of muscle attached to it were dissected out and transferred to a dish containingfrog Ringer solution at room temperature. All the drug containing solutions were freshly prepared before theexperiments Succinyl choline, Pancuronium (1,10,100μg/ml and 1mg/dl respectively Acetyl choline (10,100μg/mland 1mg/dl. Acetylcholine solution in various strength were prepared starting from 0.1% to 0.0001%.NMJblockerPancuroniumwas added to the biophase in addition to selected dose (128μgor 256μgand the contraction ofmuscle till the 70-80% of inhibition is produced and the difference from sub maximal contractions. The medianED50was interpolated from the figure taking 50%of inhibition from Height of contractionin mm. The ‘t’ test wasperformed to compare the ED50value were interpolated from the regression line to find out the ED50of the drug. Themedian doses (ED50 of both of them were calculated graphically and compared. The mean ED50 value ofsuccinylcholine was found to be 1.59 ± 0.08μg (95% confidential limit was from 1.53 to 1.66μg. The ED50ofpancuronium was found to be 0.52 ± 0.10μg with 95% confidence limit being from 0.44 to 0.60μg. The ED50valueof the two drugs was very significantly different (P < 0.001. The potency ratio of pancuronium to succinylcholinewas 0.32

  8. Response characteristics of vibration-sensitive neurons in the midbrain of the grassfrog, Rana temporaria

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Jørgensen, M B

    1989-01-01

    -locking in peripheral vibration-sensitive fibers, no phase-locking to the sinusoidal wave-form was seen in the midbrain neurons. The midbrain cells did not respond at low stimulus intensities (below 0.01-0.02 cm/s2) where a clear synchronization response occurs in saccular fibers. Six midbrain neurons had...

  9. Axonal transport of labelled proteins and increased functional activity in sciatic nerve of the frog Rana hexadactyla in vitro

    International Nuclear Information System (INIS)

    In vitro speed of fast moving labelled protein fraction was investigated in the lumbar 8 nerve of R.hexadactyla during normal and electrical stimulation conditions. 3H-leucine labelled oroteins moved in a proximo-distal direction at a speed of 144 mm/day at 25 deg C. No change was observed in the rate of proteins transported in stimulated nerves but the amount of protein bound radioactivity increased over stimulation. In ligature experiments, amount of labelled proteins accumulating at a ligature was higher in stimulated nerves. Electrical stimulation of nerve resulted in an increase in protein synthetic rate in the respective ganglion. (author)

  10. Characterization of kappa 1 and kappa 2 opioid binding sites in frog (Rana esculenta) brain membrane preparation

    International Nuclear Information System (INIS)

    The distribution and properties of frog brain kappa-opioid receptor subtypes differ not only from those of the guinea pig brain, but also from that of the rat brain. In guinea pig cerebellum the kappa 1 is the dominant receptor subtype, frog brain contains mainly the kappa 2 subtype, and the distribution of the rat brain subtypes is intermediate between the two others. In competition experiments it has been established that ethylketocyclazocine and N-cyclopropylmethyl-norazidomorphine, which are nonselective kappa-ligands, have relatively high affinities to frog brain membranes. The kappa 2 ligands (Met5)enkephalin-Arg6-Phe7 and etorphine also show high affinities to the frog brain. Kappa 1 binding sites measured in the presence of 5 microM/D-Ala2-Leu5/enkephalin represent 25-30% of [3H]ethylketocyclazocine binding in frog brain membranes. The kappa 2 subtype in frog brain resembles more to the mu subtype than the delta subtype of opioid receptors, but it differs from the mu subtype in displaying low affinity toward beta-endorphin and /D-Ala2-(Me)Phe4-Gly5-ol/enkephalin (DAGO). From our data it is evident that the opioid receptor subtypes are already present in the amphibian brain but the differences among them are less pronounced than in mammalian brain

  11. PARTIAL LIFE-CYCLE TOXICITY AND BIOCONCENTRATION MODELLING OF PERFLUOROOCTANE SULFONATE (PFOS) IN THE NORTHERN LEOPARD FROG (RANA PIPIENS)

    Science.gov (United States)

    A number of recent monitoring studies have demonstrated elevated concentrations of perfluorooctane sulfonate (PFOS) in humans and wildlife throughout the world. Although no longer manufactured in the U.S., the global distribution and relative persistence of PFOS indicates a need ...

  12. Premitotic DNA synthesis in the brain of the adult frog (Rana esculenta L.): An autoradiographic 3H-thymidine study

    International Nuclear Information System (INIS)

    Replicative synthesis of DNA in the brain of the adult frog was studied by light microscope autoradiography. Animals collected during the active period (May-June) and in hibernation (January) were used. In active frogs, 3H-thymidine labelling occurred mainly in the ependymal cells which line the ventricles. The mean labelling index (LI%) was higher in the ependyma of the lateral and fourth ventricles than in the ependyma of the lateral diencephalon and tectal parts of the mesencephalon. In the recessus infundibularis and preopticus the number of labelled cells (LCs) was several times greater than in the lateral parts of the third ventricle. LCs were seen subependymally only occasionally. The incidence of LCs in the parenchyma of the brain was much lower in most regions than in the ventricular ependyma; LCs were mainly small and, from their nuclear morphology, they were glial cells. The LI% reached the highest value in the septum hippocampi and in the nucleus entopeduncularis. In these locations, LCs were larger and closer in size to the nerve cells of these regions. From comparison with data obtained earlier in the brain of mammals, it is evident that the distribution of proliferating cells in the olfactory and limbic system is phylogenetically conservative. The occurrence of pyknotic cells in the same areas which contain LCs, suggests that cell division reflects in part the process of cell renewal observed in mammals. However, proliferating cells could also be linked to the continuous growth observed in non-mammalian vertebrates. In hibernating frogs, LCs and pyknoses were not seen or were found occasionally, which further indicates the functional significance of both processes

  13. Immunohistochemical localization of cocaine- and amphetamine-regulated transcript peptide in the central nervous system of the frog Rana esculenta

    NARCIS (Netherlands)

    Lazar, G.; Calle, M.; Roubos, E.W.; Kozicz, L.T.

    2004-01-01

    ddThe distribution of cocaine- and amphetamine-regulated transcript peptide (CARTp)-like immunoreactivity was studied only in the rat central nervous system (CNS). In mammals, CART peptides occur among others in brain areas that control feeding behavior. We mapped CARTp-immunoreactive structures in

  14. Reproduction and hybrid load in all-hybrid populations of Rana esculenta water frogs in Denmark

    DEFF Research Database (Denmark)

    Christiansen, Ditte Guldager; Fog, Kåre; Pedersen, Bo Vest; Boomsma, Jacobus Jan

    2005-01-01

    determine the genotypes of adults and abnormal and healthy offspring in three allhybrid populations of R. esculenta in Denmark. Of all eggs and larvae, 63% developed abnormally or died, with some being nonhybrid (genomes matching one of the parental species), many being aneuploid (with noninteger chromosome...... sets), a few being tetraploid, and many eggs possibly being unfertilized. The 37% surviving and apparently healthy froglets were all diploid or triploid hybrids. In all three populations, gametogenesis matched the pattern previously described for all-hybrid R. esculenta populations in which most...

  15. Correlation between chloride flux via the mitochondria-rich cells and transepithelial water movement in isolated frog skin (Rana esculenta)

    DEFF Research Database (Denmark)

    Nielsen, Robert

    Antidiuretic hormone; chloride transport; electroosmosis; Frog skin; Intercalated cells; Local osmosis; Mitochondria-rich cells.......Antidiuretic hormone; chloride transport; electroosmosis; Frog skin; Intercalated cells; Local osmosis; Mitochondria-rich cells....

  16. Una nueva especie de rana arborícola (Amphibia: Hylidae: Hyla de un bosque nublado del oeste de Venezuela

    Directory of Open Access Journals (Sweden)

    MIJARES-URRUTIA A.

    1998-01-01

    Full Text Available It is described a new species of treefrog of the genus Hyla, H. amicorum, from the Cerro Socopo, state of Falcón, western Venezuela. This new taxon can be differentiated from the congeners reported from Venezuela by the combination of characteristics as follow: small size (22.6 mm, in male, vestigial webbing between toes II and III, belly strongly areolated, skin dorsally smooth, vent covered totally by a skin fold, no pattern on dorsum, dentigerous processes of the vomer arranged forming a wide "U", located slightly behind and between the choanae. Intrageneric relationships of this new species are obscure, but a close relationships with those groups of H. minuta or H. microcephala groups would not be discarded, nevertheless as long as show unique combination of morphological characteristics, suggesting probably a different phylogenetic origin.

  17. FREE RADICALS AND THEIR ACTION IN THE MIDDLE INTESTINE STRUCTURES DURING THE METAMORPHOSIS OF RANA TEMPORARIA TEMPORARIA (LINNAEUS, 1758)

    OpenAIRE

    Vasile Sarbu; Luminta Jerca; Anica Iacobovici

    2007-01-01

    The action of free radicals in the middle intestine structures during the metamorphosis of anura amphibians represents a hint to some profound structural and ultrastructural reshuffling. By following the values of the free radicals one can observe that between the XX and XXII stages there is an explosion at the level of free radicals, whichcorresponds to the destruction of the larval epithelium at structural level. The oxidative explosion takes place with the contribution of macrophages, whos...

  18. In vitro and in vivo responses of saccular and caudal nucleus neurons in the grassfrog (Rana temporaria)

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Walkowiak, W

    1999-01-01

    We present results from in vitro and in vivo studies of response properties of neurons in the saccular and caudal nuclei in the frog. In the in vitro studies the saccular nerve of the isolated brain was stimulated with electrical pulses. In the in vivo experiments, the neurons were stimulated...

  19. 田鸡即食营养汤料的研制%The technology for instant Rana rugulosa soup

    Institute of Scientific and Technical Information of China (English)

    王平; 王秀娟

    2007-01-01

    以长白山野生资源--田鸡为原料,生产即食粉状营养保健汤料.通过正交实验和反复检测,确定了生产工艺流程 和操作要点,筛选出鲜味剂、原辅料的最佳配比,制定了产品质量标准和检测方法.

  20. 5种水产动物血红细胞形态显微观察比较及进化分析%Comparison of erythrocytes of five aquatic animals and their evolution

    Institute of Scientific and Technical Information of China (English)

    汪青; 包永波; 林志华; 刘浩明

    2011-01-01

    This paper focuses on the morphological characteristics and microstructure of erythrocytes of five aquatic animals, in order to study the morphological diversity and evolution of erythrocytes. The blood smears of five aquatic animals, bloody clam (Tegillarca granosa, Scapharca subcrenata), Carassius auratus, Rana catesbeiana and Pelodiscus sinensis, were stained by Hemacolor stain. The surface structure and morphological characteristics of erythrocytes were examined by light microscope (LM) and scanning electronic microscope (SEM). The erythrocytes of bloody clams (Tegillarca granosa & Scapharca subcrenata) had basophil granular or/and eosinophilic granular, but none was found in vertebrates erythrocytes. The size of erythrocytes increased from the two bloody clams to Bull frog (Rana catesbeiana); while the size decreased afterwards; the variation of aspect ratio and nucleocytoplasmic ratio of erythrocytes follow this trend in a similar way. The undulate fold and depression on the erythrocytes of the two bloody clams were observed apparently, and the depression was deep and wide. The surface depression was also obvious in the erythrocytes of vertebrates, although the depression faded away gradually, and no distinct surface fold was examined. These results indicated that the changes of animal erythrocytes resulted from the evolution of animals, activities and habitats, in order to obtain the biggest gas exchange efficiency and the stability of the cells.%采用Hemacolor染料对泥蚶(Tegillarca granosa)、毛蚶(Scapharca subcrenata)、鲫鱼(Carassiusauranus)、牛蛙(Rana catesbeiana)、中华鳖(Pelodiscus sinensis)等5种水产动物血细胞涂片进行染色,利用光镜和扫描电镜两种方法对5种动物的血红细胞的表面结构和形态特征进行观察。结果发现:泥蚶、毛蚶两种蚶科贝类血红细胞具有嗜酸性或嗜碱性颗粒,而鲫鱼、牛蛙、中华鳖3种水产脊椎动物

  1. Persistence at distributional edges: Columbia spotted frog habitat in the arid Great Basin, USA.

    Science.gov (United States)

    Arkle, Robert S; Pilliod, David S

    2015-09-01

    A common challenge in the conservation of broadly distributed, yet imperiled species is understanding which factors facilitate persistence at distributional edges, locations where populations are often vulnerable to extirpation due to changes in climate, land use, or distributions of other species. For Columbia spotted frogs (Rana luteiventris) in the Great Basin (USA), a genetically distinct population segment of conservation concern, we approached this problem by examining (1) landscape-scale habitat availability and distribution, (2) water body-scale habitat associations, and (3) resource management-identified threats to persistence. We found that areas with perennial aquatic habitat and suitable climate are extremely limited in the southern portion of the species' range. Within these suitable areas, native and non-native predators (trout and American bullfrogs [Lithobates catesbeianus]) are widespread and may further limit habitat availability in upper- and lower-elevation areas, respectively. At the water body scale, spotted frog occupancy was associated with deeper sites containing abundant emergent vegetation and nontrout fish species. Streams with American beaver (Castor canadensis) frequently had these structural characteristics and were significantly more likely to be occupied than ponds, lakes, streams without beaver, or streams with inactive beaver ponds, highlighting the importance of active manipulation of stream environments by beaver. Native and non-native trout reduced the likelihood of spotted frog occupancy, especially where emergent vegetation cover was sparse. Intensive livestock grazing, low aquatic connectivity, and ephemeral hydroperiods were also negatively associated with spotted frog occupancy. We conclude that persistence of this species at the arid end of its range has been largely facilitated by habitat stability (i.e., permanent hydroperiod), connectivity, predator-free refugia, and a commensalistic interaction with an ecosystem

  2. Bilan des introductions récentes d'amphibiens et de reptiles dans les milieux aquatiques continentaux de France métropolitaine

    Directory of Open Access Journals (Sweden)

    HAFFNER P.

    1997-01-01

    Full Text Available En France métropolitaine, on dénombre actuellement 36 amphibiens et 33 reptiles se reproduisant régulièrement. A deux exceptions près, les amphibiens de la faune française sont aquatiques. En revanche, seules quatre espèces de reptiles (2 tortues et 2 serpents fréquentent très régulièrement ou exclusivement les milieux aquatiques. Les introductions en milieux aquatiques effectuées depuis le début du siècle ne concernent qu'une vingtaine d'espèces d'amphibiens ou de reptiles. Le discoglosse peint (Discoglossus pictus et la grenouille taureau (Rana catesbeiana sont les deux seules espèces étrangères dont l'introduction a conduit à une naturalisation. La tortue de «Floride» (Trachemys scripta elegans pourrait bien suivre prochainement la même voie. Certaines espèces françaises ont, par contre, été introduites avec succès en métropole, hors de leurs aires d'indigénat. Les causes connues de ces introductions sont liées à des opérations à but économique (commerce, à caractère socioculturel (loisirs ou à fondement scientifique (expériences. Ces opérations n'ont cependant généralement pas pour but l'introduction volontaire d'une espèce dans le milieu naturel, celle-ci résultant plutôt de négligences. Certaines introductions involontaires ont pu aussi avoir pour origine un transport passif (par exemple, par voie maritime. Des conséquences négatives de ces introductions sont suspectées, mais ne sont généralement pas démontrées. Elles peuvent s'inscrire dans les catégories suivantes : compétition avec une espèce autochtone, prédation excessive sur une ou plusieurs espèces autochtones, pollution génétique, introduction de maladies ou de parasites.

  3. Are the hibernating water frogs from Pelophylax (Rana esculentus complex (from North-Western Romania able to adapt to the thermal water conditions?

    Directory of Open Access Journals (Sweden)

    Severus D. Covaciu-Marcov

    2009-08-01

    Full Text Available We were interested to determine if the hibernanting Pelophylax ridibundus and the othertwo forms of water frogs from the Pelophylax esculentus complex (Pelophylax lessonae, Pelophylaxesculentus fulfil the requirements of thermal resistance in order to become adapted to the thermalhabitats. During the experiment we had determined for each frog the value of two parameters: VTMaxand CTMax. The experimental determination of the resistance to temperature of the water frogs fromthe P. esculentus complex has revealed a great resistance of these frogs to high temperatures.Although the difference among the analysed frogs is not significant concerning the values of thevoluntary and critical thermal maximum, it still can be observed a specific hierarchical order. Thisresistance (an average of 34.52ºC, observed in the case of the hibernating populations of P.ridibudnus indicates the reason why the marsh frogs can adapt so easily to the conditions fromthermal waters. The voluntary thermal maximum obtained for the hybrid Pelophylax kl. esculentusdoes not differ noticeably, having an average value of 33.31ºC. The lowest values for this parameterwere recorded for the Pelophylax lessonae species (an average of 33.02ºC.

  4. The toxicity study of a systemic fungicide: artea 330 EC on the physiology and the respiratory metabolism of the tadpole (Rana saharica).

    Science.gov (United States)

    Chagra, Ali; Rouabhi, Rachid; Berrebbah, Houria; Mohammed-Reda, Djebar

    2007-01-01

    The intensification of the cereal cultures accompanied by the apparition of damaging illnesses for these cultures. These illnesses are Largely imputed to mushrooms micro and macroscopic chatty of important damages at wheat, the barley and of none targeted other animal species. The products used against these illnesses are called: Fungicides. In our work, we are interested in the survey of the effects of a systemic fungicide: the ARTEA 330 EC introduces newly in Algeria, on some physiological and metabolic parameters of a biologic model: the tadpole The exhibition of the populations of tadpoles to the different concentrations of the ARTEA 330 EC provokes a fall very important of the middleweights of the tadpoles treated. This one is reduced of meadows of 80% to the strongest concentration of ARTEA 330 EC. It is some in the same way for the reduction of the middle size of the tadpoles where one records a reduction of 25%. Concerning the percentage of mortality gotten, we observe that the one is here from 100% to the strongest concentration of ARTEA 330 EC. The breathing of the tadpoles treated by fungicide is disrupted strongly and to the strongest concentration, this one is inhibited completely. The gotten results show that the exhibition of the populations of tadpoles to the different concentrations of fungicide disrupts the physiological parameters strongly and inhibit the respiratory metabolism. A phenomenon of detoxication seems to intervene; it is put in evidence by a stimulation of the synthesis of the proteins. PMID:18399440

  5. Una especie nueva de rana venenosa de altura del género Excidobates (Dendrobatoidea: Dendrobatidae de la Cordillera del Cóndor

    Directory of Open Access Journals (Sweden)

    Ana Almendáriz C

    2012-01-01

    Full Text Available El género Excidobates está conformado por dos especies, E. captivus y E. mysteriosus, distribuidas en la cuenca del Río Marañón en Perú. Evaluaciones de la herpetofauna del bosque montano oriental de los Andes de la provincia de Zamora Chinchipe en Ecuador, resultaron en el descubrimiento de una nueva especie del género, la misma que describimos como Excidobates condor sp. nov. Proveemos información sobre su hábitat, distribución y describimos sus renacuajos. La especie se conoce de tres localidades separadas por 18 km en línea recta y genera un polígono de 7 km². Un análisis filogenético basado en los genes mitocondriales 12S y 16S rRNA sugiere que la especie nueva está cercanamente relacionada con Excidobates mysteriosus y E. captivus, de las cuales se diferencia por su patrón de coloración y la textura de la piel del dorso. Con la inclusión de la nueva especie en Excidobates ninguno de los caracteres morfológicos diagnósticos del género resulta sinapomórfico. Por lo tanto, Excidobates queda soportado solamente por caracteres genéticos. Adicionalmente se analiza las afinidades morfológicas entre los adultos y larvas de Andinobates abditus con los miembros del género Excidobates.

  6. Evidence of independent action of neurohypophyseal peptides on osmotic water flow and active sodium transport in the same target organ: studies on RANA esculenta skin and bladder (1961)

    International Nuclear Information System (INIS)

    Neurohypophyseal peptides produce on the skin and bladder of certain amphibia simultaneous increases of the passive osmotic permeability to water and active transport of sodium. The present work shows that oxytocin and two of its analogues arginine-8-oxytocin (arginine vasotocin) and lysine-8-oxytocin (lysine vasotocin) may produce the same increase of water permeability, while stimulating in quite different ways the sodium transport. This is the case for both skin and bladder. In other words, there is no correlation between natriferic and hydro-osmotic activities. The results are interpreted as evidence that neurohypophyseal hormones act on not one, as previously assumed, but two targets, inside the same epithelial cell. (author)

  7. Sobre una contracción rítmica hallada en el músculo gastronemio de la rana durante un tétanos perfecto

    OpenAIRE

    Ordóñez, J. Hernando; Franco F., Roberto; Aparicio, Julio; Salgar A., Abraham

    2011-01-01

    En las vacaciones de 1930 a 1931, me adiestraba en los trabajos prácticos del Laboratorio de Fisiología. Entre las gráficas que tomé entonces está la que se ve representada en la figura 1 (gráfica número 1, enero 15 de 193 1). Como lo que me proponía era únicamente ponerme práctico en el manejo de los aparatos, desprecié un fenómeno que se presentó a mi vista y seguí tomando gráficas, ya en unas condiciones, ya en otras, sin habérseme ocurrido siquiera apuntar el dispositivo experimental con ...

  8. Surmanuhtlus kõrgeima võimaliku karistusmäärana : [bakalaureusetöö] / Katrin Roosmaa ; Tartu Ülikool, õigusteaduskond ; juhendaja: Silvia Kaugia

    Index Scriptorium Estoniae

    Roosmaa, Katrin, 1984-

    2007-01-01

    Surmanuhtluse olemus ja selle karistusliigiga sanktsioneeritud teod Eestis lähiminevikus, surmanuhtluse määramine ja täideviimine kuni 1998. a.-ni, surmanuhtluse kaotamise direktiiv ning seda toetavad ja mittetoetavad riigid, levinumad poolt- ja vastuargumendid, Eesti elanikkonna suhtumine

  9. Spatial Amphibian Impact Assessment – a management tool for assessment of road effects on regional populations of Moor frogs (Rana arvalis)

    DEFF Research Database (Denmark)

    Pontoppidan, Maj-Britt; Nachman, Gøsta Støger

    2013-01-01

    An expanding network of roads and railways fragments natural habitat affecting the amount and quality of habitat and reducing connectivity between habitat patches with severe consequences for biodiversity and population persistence. To ensure an ecologically sustainable transportation system it is...... essential to find agreement between nature conservation and land use. However, sustainable road planning requires adequate tools for assessment, prevention and mitigation of the impacts of infrastructure. In this study, we present a spatially explicit model, SAIA (Spatial Amphibian Impact Assessment), to be...... used as a standardized and quantitative tool for assessing the impact of roads on pond-breeding amphibians. The model considers a landscape mosaic of breeding habitat, summer habitat and uninhabitable land. As input, we use a GIS-map of the landscape with information on land cover as well as data on...

  10. GROWTH AND METAMORPHOSIS IN TADPOLES OF RANA PRETIOSA PRETIOSA, TREATED WITH RECOMBINANT PORCINE GROWTH HORMONE, PROLACTIN, SOMATOSTATIN (SRIF AND ANTI-SRIF

    Directory of Open Access Journals (Sweden)

    Ewen McLean

    1998-07-01

    Full Text Available The effect of prolactin (PRL, growth hormone (GH, somatostatin (SRIF and anti-SRIF (αSRIF treatment upon growth and metamorphosis of western spotted frog tadpoles, T a y l o r and K o l l r o s (1946 stage (TK st. XVI (n = 18/group was examined. Treated animals received 2.5 g protein/g body weight every 5 days until one group exhibited > TK st. XXIV and complete terrestrialization. Administration of GH and PRL resulted in 18/18 and 15/18 animals respectively expressing complete terrestrialization. 12/18 SRIF injected tadpoles achieved > TK st. XXIV. In contrast, only 5 each of control and SRIF treated tadpoles transformed to > st. XXIV. Significantly higher (P<0.05 length: weight ratios were recorded for control versus all other treatment groups. PRL and αSRIF treated animals exhibited reduced body length: fore limb length ratios (P<0.05 when compared to controls. Greater hind-limb length was noted in animals treated with GH, SRIF and PRL. PRL treatment resulted in significantly increased length and weight (P<0.05 when compared to controls, and highly significant (P<0.01 reduction in condition factor compared against all other treatment groups.

  11. ULTRASTRUCTURE OF PERIPHERAL BLOOD CELLS OF RANA RUGULOSA%虎纹蛙外周血细胞的超微结构

    Institute of Scientific and Technical Information of China (English)

    潘鸿春

    2001-01-01

    目的:观察虎纹蛙外周血细胞的超微结构.方法:运用透射电镜技术.结果:在外周血细胞中可区分出红细胞,单核细胞,淋巴细胞,中性粒细胞,嗜酸性粒细胞,嗜碱性粒细胞和血小板细胞.与哺乳纲动物不同,虎纹蛙白细胞表面均有伪足.结论:脊椎动物白细胞形态结构的分化程度可能与动物的分类地位有关.#

  12. PCR Amplification and SSCP Analysis of Sox Gene of Rana Rugulosa Wiegmann%虎纹蛙Sox基因的PCR扩增及SSCP分析

    Institute of Scientific and Technical Information of China (English)

    张小爱; 张海军; 聂刘旺; 阚显照

    2001-01-01

    本文采用PCR技术,以特异扩增人SRY基因HMG-box保守区的一对引物,扩增了虎纹蛙Sox基因(SRY-box gene).并对扩增产物进行了SSCP分析.结果雌雄虎纹蛙个体均扩增出一条带,大小为221 bp,表明虎纹蛙Sox基因在雌雄个性间无性别特异性.SSCP分析结果显示虎纹蛙Sox基因雌雄个体片段的单链迁移率无差异,而与人的有较大差异.本文为探讨虎纹蛙的性别决定机制及Sox基因的进行提供了分子资料.

  13. Structural and functional identification of the pituitary adenylate cyclase-activating polypeptide receptor VPAC2 from the frog Rana tigrina rugulosa.

    Science.gov (United States)

    Hoo, R L; Alexandre, D; Chan, S M; Anouar, Y; Pang, R T; Vaudry, H; Chow, B K

    2001-10-01

    Recently, a frog pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) receptor (fPVR) has been characterized, and interestingly, this receptor exhibits characteristics of both mammalian PACAP type II receptors VPAC(1)R and VPAC(2)R. In order to investigate the receptors responsible for mediating the actions of VIP and PACAP in amphibians, in this report, a frog VPAC(2) receptor (fVPAC(2)R) cDNA was isolated. fVPAC(2)R shares 47.7, 46.9 and 62.5% amino acid sequence identity with fPVR, human VPAC(1)R and human VPAC(2)R respectively. Functionally, fVPAC(2)R, when expressed in CHO cells, was responsive to both frog peptides including VIP, PACAP38 and PACAP27 where the EC(50) values of these peptides in intracellular cAMP production were 0.15, 0.18 and 0.16 microM respectively. The pharmacological profiles of human peptides (VIP, PACAP38 and peptide histidine methionine) to stimulate frog and human VPAC(2)Rs were compared, and it was found that these peptides could only activate the frog receptor at micromolar concentrations. fVPAC(2)R was found to be widely distributed in various peripheral tissues as well as several regions of the brain. The presence of the receptor transcripts suggests the functional roles of the receptor in mediating the actions of PACAP and/or VIP in these tissues. As VIP and particularly PACAP27 are highly conserved peptides in vertebrate evolution, comparative studies of these peptides and their receptors in non-mammalian vertebrates should provide clues to better understand the physiology of these important peptides in human and other vertebrates. PMID:11564605

  14. Further investigation of the spontaneous and evoked activity of the primary neurons of statoreceptors (and other receptors) of the labyrinth of the bullfrog before, during and after an extended period of weightlessness, including alternative intervals of artificial gravity

    Science.gov (United States)

    1977-01-01

    Vestibular neuron activity was examined by studying nerve stimulation and evoked response. A cooling element, applied to the nerve consisted of a silver hook through which a coolant fluid flowed. Temperature changes were recorded via microtermistors on an eight channel brush recorder, together with response. Diffusion of the cooling effect was measured, recovery time was assessed, and the nerve was then studied hystologically and ultrastructurally. Problems in frog preparation were discussed along with problems in maintaining healthy specimens and bacteria controlled aquaria.

  15. 牛蛙mtDNA的一种提取方法及初步酶切分析%An Abstract Method of Bullfrog's mtDNA and its Initial Enzymatic Analyses

    Institute of Scientific and Technical Information of China (English)

    李焰焰; 聂传朋

    2001-01-01

    本文中使用牛蛙作为材料提取mtDNA进行RFLP分析.探讨提取牛蛙mtDNA的方法及酶切图谱.结果表明,按本实验操作方法能够提取足量牛蛙的mtDNA,用以酶切分析.采取KpnI.Xho.SacI.PstI.HindⅢ等五种限制性内切酶酶切牛蛙mtDNA,能够粗略求出它的分子量大约在20kb左右.

  16. Fate, behavior, and bioavailability of metal and metal oxide nanomaterials in terrestrial ecosystems

    Science.gov (United States)

    Bertsch, P. M.; Unrine, J. M.; Judy, J.; Tsyusko, O.

    2012-12-01

    as referenced to the free metal ion concentration, and gene and protein expression associated with nanoparticle exposure. The results demonstrate the importance and challenges of characterization of nanoparticles under varying chemical conditions associated with exposure media. We have also demonstrated that metal and metal oxide nanoparticles are bioavailable and can be toxic to microorganisms, plants, nematodes, and earthworms. The results also suggest a different spatial distribution in tissues as well as unique toxicity mechanisms compared to the free metal ion concentration. Ongoing studies are evaluating the propensity for nanoparticles to be transferred from one trophic level to the next by feeding pre-exposed microorganisms (B. vietnamensis) to the nematode, C. elegans, pre-exposed earthworms (E. fetida) to bullfrogs (R. catesbeiana) and pre-exposed tobacco plants (Nicotiana tabacum L. cv Xanthi) to the caterpillar, tobacco horn worm (Manduca sexta), to test the hypothesis that surface modification of nanoparticles by peptides or other biomolecules facilitate the transmembrane transport of nanoparticles, thus enhancing the bioavailability to higher trophic levels.

  17. Evolution of genomes in the hybridogenetic populations modelled by the Penna model

    OpenAIRE

    Kula, Mateusz; Bonkowska, Katarzyna; Ogielska, Maria; Kierzkowski, Piotr; Zalesna, Anna; Cebrat, Stanislaw

    2009-01-01

    Background: Hybridogenesis is a very interesting example of reproduction which seems to integrate the sexual and clonal processes in one system. In a case of frogs, described in the paper, two parental species - Rana lessonae and Rana ridibunda can form fertile hybrid individuals - Rana esculenta. Hybrid individuals eliminate one parental haplotype from their germ line cells before meiosis (end before recombination) which implicates clonal reproduction of the haplotype transferred to the game...

  18. Rediscovery of Pelobates fuscus insubricus in the Asti Province, north-western Italy

    OpenAIRE

    Vincenzo Mercurio; Fabrizio Li Vigni

    2007-01-01

    The amphibians of the pond complex “Stagni di Belangero” in the Po Plain, Asti Province, have been studied. The species living in the pond are Bufo bufo, Bufo viridis, Hyla intermedia, Pelobates fuscus, Rana dalmatina, Rana synklepton esculenta, Rana cf. kurtmuelleri, Triturus carnifex and Triturus vulgaris. Species composition, migration period of P. fuscus, and biometric data are provided. Relevant importance has been given to P. fuscus, since we reconfirm its presence in one...

  19. Helminthen einheimischer Froschlurche

    OpenAIRE

    Andreas, Katharina

    2010-01-01

    176 frogs of the species Rana kl. esculenta (n = 137), Rana ridibunda (n = 7), Rana temporaria (n = 19), Rana arvalis (n = 18) and Bufo bufo (n = 1) taken from 11 different habitats in the Brandenburg state and the state of Saxonia-Anhalt were dissected and helminthologically examined. One aim of this study was to show the role of indigenous frogs in the epidemiology of trematode infections of carnivorous mammals and birds more closely, and also to attain details the incidence of frogs wi...

  20. A Model for Taxonomic Work on Homoxenous Coccidia: Redescription, Host Specificity, and Molecular Phylogeny of Eimeria ranae Dobell, 1909, with a Review of Anuran-Host Eimeria (Apicomplexa: Eimeriorina)

    Czech Academy of Sciences Publication Activity Database

    Jirků, Miloslav; Jirků, Milan; Oborník, Miroslav; Lukeš, Julius; Modrý, David

    2009-01-01

    Roč. 56, č. 1 (2009), s. 39-51. ISSN 1066-5234 R&D Projects: GA ČR GA206/03/1544 Institutional research plan: CEZ:AV0Z60220518 Keywords : Amphibia * Anura * experimental infections * metamorphosis * morphotypes * SSU rDNA sequence * tadpoles * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.355, year: 2009

  1. GİRİŞİMCİ VE YÖNETİCİ KADINLARIN PROFİLLERİ FARKLI MIDIR? Doç.Dr.Rana ÖZEN KUTANİS, Arş.Gör.Sümeyra ALPASLAN

    OpenAIRE

    ,

    2006-01-01

    Reklâmlar, tüketicilerin satın alma kararlarında önemli bir etkiye sahiptir. Reklâmlarda ki yanıltıcı unsurlardan dolayı tüketiciler aldanabilmektedir. Bunun için işletmeler, tüketiciye ve topluma karşı sosyal sorumlulukları gereği yanıltıcı reklâmlardan kaçınmalıdır. Bu çalışmada, Afyonkarahisar Kocatepe Üniversitesi’nde öğrenim gören öğrencilerin medya araçlarında yayınlanan reklâmlara ilişkin algılamaları ölçülmüştür. Çalışmanın sonucuna göre pazarlama etiği ve sosyal sorumluluk ilkelerine...

  2. 亚急性镉暴露对雄性黑斑蛙生殖毒性的研究%Study on the reproductive toxicity of subacute cadmium exposure in male Rana nigromaculata

    Institute of Scientific and Technical Information of China (English)

    贾秀英; 汪美贞

    2007-01-01

    在实验条件下,将健康性成熟雄性黑斑蛙暴露于2.5、5.0、7.5和10.0mg·L-1浓度的镉溶液中14d,观察和分析黑斑蛙的精子数量、精子畸形率,测定精巢组织中酸性磷酸酶(ACP)、乳酸脱氢酶(LDH)、丙二醛(MDA)、谷胱甘肽(GSH)、超氧化歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)的水平和活力,以探讨镉对黑斑蛙的雄性生殖毒性及作用机理.结果表明:①镉可引起黑斑蛙精子数量减少和精子畸形率增加,且呈剂量-效应关系;②镉可引起精巢ACP、LDH酶活性的降低,且随染毒剂量的增加而降低;③镉可引起精巢组织MDA、GSH含量的升高,引起抗氧化酶SOD、GSH-Px活性的降低.由此推论,亚急性镉暴露对黑斑蛙精巢有明显的毒性作用,其机制与镉致黑斑蛙精巢组织标志酶活力的降低和精巢脂质过氧化作用有关.

  3. Variación interpoblacional y ontogenética en la dieta de la rana llorona Physalaemus albonotatus (Anura: Leiuperidae Interpopulation and ontogenetic variation in the diet of the menwig frog Physalaemus albonotatus (Anura: Leiuperidae

    Directory of Open Access Journals (Sweden)

    Diego Alejandro Falico

    2012-12-01

    Full Text Available Se analizó y comparó el espectro trófico de 2 poblaciones de Physalaemus albonotatus que habitan en ecosistemas diferentes: a un terreno baldío urbano y b un área protegida del valle aluvial del río Paraná Medio. La dieta de Physalaemus albonotatus está compuesta fundamentalmente de hormigas, coleópteros, colémbolos e isópodos, pero con numerosas presas secundarias. Al comparar 3 grupos etarios de los individuos en cada población (adultos, subadultos y jóvenes se encontró una variación ontogenética relacionada con el volumen, cantidad y tipo de presa ingerida. Los anfibios adultos consumieron mayor cantidad de presas y más voluminosas, pero el nicho trófico de los jóvenes fue más amplio. Entre los adultos, la similitud de la dieta entre sexos fue muy elevada, aunque las hembras consumieron más hormigas que los machos. Si bien el solapamiento trófico entre las poblaciones fue elevado, la amplitud trófica resultó mayor en la población del humedal fluvial. Las diferencias en la alimentación encontradas entre las 2 poblaciones y lo registrado en otros trabajos realizados en diferentes ambientes reflejan la plasticidad trófica de este anuro, característica que le permite prosperar en hábitats diversos, incluso en los muy antropizados.We analyzed and compared the feeding of 2 populations of Physalaemus albonotatus inhabiting different ecosystems: a an urban vacant lot, and b a protected area of Middle Paraná River floodplain. The diet of Physalaemus albonotatus is mainly composed by ants, beetles, springtails and woodlouses, but also included several secondary preys. While comparing adults, subadults and juveniles diet on each population, we found an ontogenetic diet variation related to changes in prey type and volume as well as in number of prey items per gut. Bigger frogs consumed a greater amount of prey and more voluminous arthropods, while juveniles had a larger trophic niche breadth. Despite the great similarity in diet between sexes, adult females consumed a larger amount of ants than males did. Although trophic niche overlap between both populations was high, trophic niche breadth was wider for Paraná River floodplain population. Feeding differences found between studied populations and populations inhabiting other environments as described on literature reflects the trophic plasticity of this species and its capacity to thrive at different habitats, including markedly anthropogenically impacted environments.

  4. Histochemical localization of six types of enzymes in the digestive mucosa of Rana rugulosa%虎纹蛙消化道黏膜6种酶的组织化学定位

    Institute of Scientific and Technical Information of China (English)

    吕大成; 祝小琴; 张敏; 潘慧敏; 诸晓月; 张盛周

    2015-01-01

    目的 研究虎纹蛙消化道不同部位酸性磷酸酶(ACP)、碱性磷酸酶(ALP)、过氧化物酶(POX)、非特异性酯酶(NSE)、腺苷三磷酸酶(ATPase)、琥珀酸脱氢酶(SDH)等6种酶的活力分布.方法 消化道分8个部位取材,应用冰冻切片、石蜡切片、酶组织化学技术及光密度定量分析.结果 ACP在十二指肠活力最高,食管、贲门和直肠其次,其余各部位酶活力显著较低(P<0.05).ALP主要分布于空肠和十二指肠,胃体和幽门中几乎检测不出酶活力.POX在食管和胃体活力显著较高(P<0.05),在空肠和回肠酶活力显著较低(P<0.05).NES在消化道各部位均有较多分布,其中以胃体、幽门和十二指肠酶活力显著较高(P<0.05),食管和直肠酶活力显著较低(P<0.05).ATPase在贲门活力最高,在回肠和直肠酶活力显著较低(P<0.05).SDH在食管、胃体和直肠活力较高,在幽门酶活力显著较低(P<0.05).结论 虎纹蛙消化道黏膜各种酶的活力分布与其他动物有一定的相似性,但其与脂类消化吸收相关酶的分布显示了明显的物种特异性.

  5. Inumunohistochemical localization of two kinds of endocrine cells in digestive tract of rana rugulosa%虎纹蛙消化道两种内分泌细胞的免疫组织化学定位

    Institute of Scientific and Technical Information of China (English)

    张盛周; 吴孝兵; 陈壁辉

    2002-01-01

    目的:研究虎纹蛙消化道5-羟色胺和生长抑素免疫阳性细胞的形态与分布.方法:免疫组织化学技术.结果:5-羟色胺免疫阳性细胞在消化道各段均有分布.十二脂肠密度最高,直肠其次,食道最低.生长抑素免疫阳性细胞主要分布于胃幽门部和胃体,小肠各段亦有少数分布,直肠和食道中没有.结论:虎纹蛙消化道5-HT和SS免疫阳性细胞的分布和形态特点与多种动物相似.

  6. A Study on the Activities of Amylase and Lipase in Digestive Tract of Rana rugulosa%虎纹蛙消化道淀粉酶和脂肪酶活力研究

    Institute of Scientific and Technical Information of China (English)

    李庆; 张雪; 余昌萍; 汪娟; 余晶晶; 张盛周

    2014-01-01

    以酶学分析方法研究了虎纹蛙消化道淀粉酶和脂肪酶的分布以及pH和温度对这两种消化酶活力的影响.结果表明:在各自生理pH值条件下,虎纹蛙消化道不同部位淀粉酶活力大小顺序依次为前肠>中肠>后肠>食道>胃,胃和肠淀粉酶最适pH值分别为8.6和7.0,最适温度分别为35℃和40℃.脂肪酶活力大小顺序依次为中肠>后肠>前肠>胃>食道,各部位之间差异显著(P<0.05),胃和肠脂肪酶的最适pH值均为9.0,最适温度分别为50℃和55℃.

  7. Differences in mGnRH and cGnRH-II contents in pituitaries and discrete brain areas of Rana rugulosa W. according to age and stage of maturity.

    Science.gov (United States)

    Yuanyou, L; Haoran, L

    2000-02-01

    (1) In tadpoles, chicken-II gonadotropin-releasing hormone (cGnRH-II) could be measured in the brains before metamorphosis, but mammalian gonadotropin-releasing hormone (mGnRH) did not appear until the stage of metamorphosis, i.e. cGnRH-II appeared earlier than mGnRH during ontogenesis. (2) During the metamorphic climax, mGnRH content increased more rapidly than cGnRH-II; the content of mGnRH was about two times of that of cGnRH-II. (3) In juveniles and adults, the content of mGnRH and cGnRH-II, and the distribution pattern of mGnRH (but not cGnRH-II) in the brains and pituitaries changed with age and stages of gonadal development. mGnRH mainly distributed in the rostral brain areas, whereas cGnRH-II had a widespread distribution in the brain. (4) Both mGnRH and cGnRH-II were present in the pituitaries at each stage of maturity. The gonadotropin-releasing hormone (GnRH) content at sexually maturity was significantly higher than that at other stages of gonadal development, and the content of mGnRH was about 15-18 times of that of cGnRH-II. (5) These results suggest that both mGnRH and cGnRH-II are potentially involved in the direct regulation of pituitary gonadotropes, and mGnRH may be the major active form, cGnRH-II may also serve as a neurotransmitter or neuromodulator in the brain. PMID:11790340

  8. Isolation and identification of pathogen of the cataract disease and its immunological control in Rana tigrina rugulosa%虎纹蛙白内障病病原的分离鉴定及其免疫防治

    Institute of Scientific and Technical Information of China (English)

    周永灿; 朱传华; 陈国华; 苏文强; 唐泽锋

    2001-01-01

    本文报道了海南养殖虎纹蛙白内障病的病原及其免疫学防治方法.对该典型患病个体进行病原分离并鉴定表明,被分离出的病原为脑膜炎败血黄杆菌.在所实验的20种抗菌药物中,该菌只对万古霉素敏感,对头孢哌酮中度敏感,而对其他18种药物均不敏感.通过筛选该病原强毒株制备甲醛灭活疫苗,对健康虎纹蛙进行免疫接种后,可明显提高其对该病的抵抗能力,表明在生产上用免疫学方法防治该病是可行的.

  9. 环境因素对虎纹蛙胚胎发育的影响%The Influence of the Environmental Factors on the Embryonic Development of Rana tigrina rugulosa

    Institute of Scientific and Technical Information of China (English)

    刘楚吾; 徐贺伦; 冯超源; 刘丽

    2001-01-01

    就温度、盐度、pH值及水中溶氧四个环境因素对虎纹蛙胚胎发育的影响进行了系统研究.结果表明:其适宜的孵化水温为20~30℃,在此温度范围内,随着温度的升高,胚胎发育速度加快,水温在(30±1)℃时,胚胎发育到鳃盖完成期需58.8 h,孵化率为84.2%;水温(20±0.5)℃时,需203.9 h,孵化率为89.0%;水温(25±1)℃时,需时84.0 h,孵化率最高,达94.5%.盐度对虎纹蛙胚胎发育影响很大,盐度越高,胚胎畸形率越高,且发育经历时间越长,孵化水体的盐度应在1.9以下,最适宜用淡水孵化.pH过高或过低都对胚胎发育不利,孵化水体的pH值以6.5~8.5为宜.虎纹蛙胚胎发育的不同阶段对水中溶氧量要求不同,在肌肉效应期、鳃血循环期和鳃盖完成期,水中溶氧的半致死浓度分别为0.57 mg/L、1.13 mg/L和0.40 mg/L.

  10. Cloning and Sequence Analysis of Sox Gene in Rana Rugulosa Wie gmann%虎纹蛙四个Sox基因的克隆及序列分析

    Institute of Scientific and Technical Information of China (English)

    张小爱; 聂刘旺; 张海军

    2001-01-01

    参照人SRY基因HMG-box保守区的序列,设计一对兼并引物, 扩增了虎纹蛙的Sox基因,并对扩增产物进行了克隆和测序.结果在雌雄个体中共筛选出四个不同的Sox基因,其序列与人相应SOX基因的相似性分别为92%、94%、98%和98%.本研究为探索虎纹蛙的性别决定机制提供了分子资料.

  11. Studies on the Mast Cells in the Tongue of Frog (Rana tigrina rugulosa) by Histochemical and Immunohistochemical Method%虎纹蛙舌肥大细胞组化及免疫组化

    Institute of Scientific and Technical Information of China (English)

    林旋; 王寿昆; 林树根; 陈梅芳; 李玲玲

    2014-01-01

    应用改良甲苯胺蓝(MTB)、阿尔新蓝-藏红O(AB/SO)、甲基绿-派洛宁(MG-P)、天青Ⅱ-伊红-瑞氏混合液等4种组化染色技术进行染色,并用小鼠抗人肥大细胞类胰蛋白酶单克隆抗体AAl通过ElivisionTM免疫组化染色方法,对虎纹蛙舌头肥大细胞进行染色.结果表明:虎纹蛙舌头中的肥大细胞,大小形态不一.虎纹蛙舌组织中分布有大量肥大细胞,主要分布于固有层的结缔组织中和舌头腺体之间,肌层也可见到大量的肥大细胞,并且有沿血管分布的特点.在用ElivisionTM免疫组化染色方法中,单克隆抗体AAl与虎纹蛙舌头组织中肥大细胞中的类胰蛋白酶有良好的交叉反应.类胰蛋白酶阳性细胞数量很少,分布于舌组织固有层和腺体之间.而人胃癌间质中可见多量类胰蛋白酶阳性细胞.

  12. Effects of Dopaminergic Drugs on the Secretion of Gonadotropin-releasing Hormone and Luteinizing Hormone in Rana rugulosa%多巴胺能药物对虎纹蛙GnRH和LH分泌活动的影响

    Institute of Scientific and Technical Information of China (English)

    李远友; 林浩然

    2002-01-01

    利用在体注射实验和放射免疫测定法,研究了多巴胺能药物对性腺处于再发育期虎纹蛙的促性腺激素释放激素(GnRH)及促黄体激素(LH)分泌活动的影响.结果是:多巴胺(DA)及其激动剂阿扑吗啡(APO)可显著降低血浆LH水平;而多巴胺的拮抗剂--地欧酮(DOM)可显著增加垂体LH含量.DA对脑中cGnRH-Ⅱ的合成有抑制作用,而DOM对其mGnRH的释放有一定的刺激作用.结果表明:DA可在脑及垂体水平分别抑制虎纹蛙GnRH和LH的释放,DA对LH释放的抑制作用很可能是通过D2受体实现的.

  13. An investigation on infection of Sparganum in Rana rugulosa and observation of animal model establishment on different host%虎纹蛙感染裂头蚴的调查与动物宿主感染观察

    Institute of Scientific and Technical Information of China (English)

    王贵燕; 王敏; 刘冠琪; 高现灵; 关小燕; 邰闪闪; 李美玉; 陈剑煌; 黄锦桃

    2014-01-01

    目的 调查虎纹蛙自然感染裂头蚴的情况,取裂头蚴感染实验鼠和家犬,为实验教学提供依据.方法 解剖虎纹蛙收集裂头蚴,将裂头蚴感染昆明鼠和BALB/c小鼠(6条/只)和SD大鼠(10条/只),对照组灌注生理盐水;60d后解剖实验动物,收集小鼠体内裂头蚴,并取裂头蚴寄生部位组织包埋切片.将虎纹蛙和鼠体内收集的裂头蚴分别感染家犬6条/只,在感染46 d后取粪便检查,感染60d后解剖家犬.结果 野生虎纹蛙自然感染率为40.63%(403/992);解剖实验组昆明鼠、BALB/c小鼠和SD大鼠肉眼可见皮下肌肉组织有弥漫性瘀血斑点和包块形成,镜下观察见裂头蚴周围有囊壁包绕,纤维组织增生;家犬粪检查到曼氏迭宫绦虫卵,解剖家犬收集到曼氏迭宫绦虫成虫.结论 广州市花都区野生虎纹蛙裂头蚴的感染率较高;昆明鼠、BALB/c小鼠和SD大鼠均可作为曼氏迭宫绦虫的转续宿主;家犬是该虫适宜的终末宿主.

  14. Influence of Erythrocyte (RBC) and Hemoglobin (Hb) in Tiger Frog Rana tigerina rugulosa Wiegmann Under of Acid Stress%酸胁迫对虎纹蛙红细胞及血红蛋白的影响

    Institute of Scientific and Technical Information of China (English)

    邵晨; 施时迪; 谢建芳

    2005-01-01

    采用室内水族箱培养方法,研究了不同酸梯度对虎纹蛙(Ranatigerina rugulosaWiegmann)红细胞和血红蛋白的影响.结果表明,在pH3.5~pH5.0之间,酸胁迫对虎纹蛙的红细胞数量及血红蛋白含量具有较明显的剂量效应,其中pH3.5条件下对虎纹蛙红细胞和血红蛋白产生了较强的毒害作用,并且随着时间的推移对红细胞及血红蛋白的影响呈现逐渐加重的趋势.随着pH值的上升,其红细胞数量和血红蛋白含量也逐渐增大.pH值≥pH5.5可能是虎纹蛙较为适宜的水体环境.试验表明,酸胁迫可对虎纹蛙造成较为严重的危害,可将虎纹蛙红细胞数量和血红蛋白含量的变化作为检测水体酸污染的指标和手段.

  15. Synthesis and intracellular transport of proteins in the exocrine pancreas of the frog (Rana esculenta). II. An in vitro study of the transport process and the influence of temperature.

    Science.gov (United States)

    Slot, J W; Geuze, J J

    1976-03-16

    Frog pancreatic tissue was pulse-labelled in vitro with 3H-leucine and protein transport was studied in exocrine cells by electron microscope autoradiography. The proteins appeared to be synthesized in the RER and transported to the secretory granules along a similar route and with the same velocity as previously described under in vitro conditions. Evidence was obtained for the involvement of the vesicular and tubular elements at the periphery of the Golgi system in transferring protein from the RER to the Golgi cisternae. Kinetics of the release of newly synthesized proteins from the RER and their appearance in the condensing vacuoles are discussed and related to results reported from other tissues. The transport velocity in this poikilothermic system was studied in relation to the incubation temperature and compared with results reported from its mammalian counterpart. At temperatures between 20 and 30 degrees C intracellular protein transport occurs faster in the frog than in the Guinea pig pancreas. At higher temperature the transport process was severely disturbed in the frog. PMID:1083293

  16. Bits and Pieces ehk kolumna / DJ Pickney Tiger

    Index Scriptorium Estoniae

    DJ Pickney Tiger, pseud., 1970-

    2009-01-01

    Tutvustused: XXI Sajandi Orkester. Kaheksa. Tallinn : XXI Sajandi Orkester, 2006 ; XXI Sajandi Orkester. Üheksa. Tallinn : XXI Sajandi Orkester, 2008 ; Silent Bass. Crosshatched. Germany : Laika, 2008 ; Bullfrog Brown with Steve Lury. 2009

  17. Popmuusika / Valner Valme

    Index Scriptorium Estoniae

    Valme, Valner, 1970-

    2006-01-01

    Uutest heliplaatidest Nits "Les Nuits", Bullfrog Brown "Snakes & Devils", "Motown remixed", "The Dukes Of Hazzard", Critical "Chapter One ehk Teine Maitse", The Dandy Warhols "Odditorium Or Warlords Of Mars", Solveig Slettahjell Slow motion Quintet "Pixiedust"

  18. Plaadid / Tiit Kusnets

    Index Scriptorium Estoniae

    Kusnets, Tiit

    2004-01-01

    Uutest plaatidest Luavrik Luavrik "Passioon & Fuuga", Arve Henriksen "Chiaroscuro", Bullfrog Brown "Mudhole Stories", "Scoonby-Doo 2", Bela fleck & Edgar Mayer "Music For Two", Christiana Milian "It's About Time"

  19. Kuula ka neid / Joosep Sang

    Index Scriptorium Estoniae

    Sang, Joosep

    2009-01-01

    Heliplaaditutvustused: Bullfrog Brown with Steve Lury. KWAQ Records, 2009; Grupa Janke Randalu. Live. [Saksamaa] : Jazz'n'Arts, 2008; Paha Polly. Ei jäägi üle muud... [Tartu] : Forward, 2008. Uutest heliplaatidest

  20. 50 CFR 17.43 - Special rules-amphibians.

    Science.gov (United States)

    2010-10-01

    ... intentional introduction of species into a stock pond that may prey on California tiger salamander adults... intentional introduction of species into a stock pond (including non-native fish and bullfrogs) that may...

  1. Salida de campo a Laguna de Duero, Valdestillas y Villanubla, en Valladolid, el 24 de agosto de 1952

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salidas de campo simultáneas a Laguna de Duero, Valdestillas y Villanubla, en Valladolid, del autor, Mariano Sáiz Pardo y Luis Valverde Gómez, respectivamente, el 24 de agosto de 1952, de las que el autor anotó observaciones sobre los siguientes anfibios: ranas (sin concretar la especie), Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por el autor) y Pleurodeles waltl (Gallipato, que en este caso puede referirse a una observación errónea, ya que el a...

  2. UTJECAJ BIOFILMA NA CIJELJENJE RANE I POSTUPAK ZA IDENTIFIKACIJU BIOFILMA U RANI

    OpenAIRE

    Škrlin, Jasenka

    2016-01-01

    Mikroorganizmi mogu postojati kako u planktonskom, tako i u stanju biofi lma. Svaki fenotip ima ulogu u zakašnjelom zacjeljivanju te uzrokuje infekcije akutnih i kroničnih rana. Međutim, virulentni biofi lm je osnovni razlog da do zacjeljivanja rana ne dolazi pravodobno. Zbog hipoteze da mikroorganizmi mogu adherirati za svaku površinu, biofilm se može naći u svim kroničnim ranama. Međutim, sam po sebi biofi lm nije najveća prepreka zacjeljivanju kroničnih rana, već njegova virulentnost i pat...

  3. Tectonic and neotectonic framwork of the Yucca Mountain region, Task 5

    Energy Technology Data Exchange (ETDEWEB)

    Schweickert, R.A.

    1993-09-30

    Research continued on the tectonic and neotectonics of the Yucca Mountain region. Highlights from projects include: structural studies in Grapevine Mountains, Funeral Mountains, Bullfrog Hills, and Bare Mountain; development of structural models for pre-Middle Miocene normal and strike-slip faulting at Bare Mountain; Paleomagnetic analysis of Paleozoic and Cenozoic units at Bare Mountain; sampling of pegmatites in Bullfrog Hills and Funeral Mountains for U-Pb isotopic analysis; and review and analysis of Mesozoic structure between eastern sierra and Nevada test Site.

  4. Un élevage de grenouilles-taureaux aux Philippines

    Directory of Open Access Journals (Sweden)

    Hardouin, J.

    1991-01-01

    Full Text Available Breeding of bull-frogs (Pana castebeiana in the Philippines. The importations of frogs in the European Economic Community are worth 20-40 millions ECU yearly ; Asia is the most important area of supply. Frog breeding is difficult and nearly all the trade is based on gathering in the wild. The article gives some information on a commercial frog farm near Manila in the Philippines, where the bull-frog initially imported from U.S.A. is bred. The whole production cycle is controlled. This enterprise could serve as a model for edible African species, which are much doser to our green European frogs.

  5. Genetic structure of the marsh frog (Pelophylax ridibundus) populations in urban landscape

    Czech Academy of Sciences Publication Activity Database

    Mikulíček, Peter; Pišút, P.

    2012-01-01

    Roč. 58, č. 5 (2012), s. 833-845. ISSN 1612-4642 Institutional support: RVO:68081766 Keywords : Genetic differentiation * Habitat fragmentation * Microsatellites * Rana ridibunda * Ranidae * Urbanization Subject RIV: EG - Zoology Impact factor: 1.355, year: 2012

  6. Exploratory evaluation of nutrient enrichment and frog response at Conboy Lake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We sampled nutrient and water quality parameters and surveyed Oregon spotted frogs (Rana pretiosa) life stages (eggs, larvae and recently metamorphosed juveniles)...

  7. Report on Oregon Spotted Frog Egg Mass Surveys 2013-2015

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Oregon spotted frogs (Rana pretiosa) were once common across wetlands throughout western Washington and Oregon and were found in northern California and southern...

  8. Resurrecting an Extinct Species: Archival DNA, Taxonomy, and Conservation of the Vegas Valley Leopard Frog

    Science.gov (United States)

    Suggestions that the extinct Vegas Valley leopard frog (Rana fisheri = Lithobates fisheri) may have been synonymous with one of several declining species has complicated recovery planning for imperiled leopard frogs in southwestern North America. To address this concern, we recon...

  9. A natriferic principle other than arginine-vasotocin in the frog neuro hypophysis (1961)

    International Nuclear Information System (INIS)

    In the neurohypophysis of Rana esculenta there exists, in addition to vasotocin, an unknown active principle which accounts for approximately half of the total natriferic activity of the gland. This principle is not found in chickens. (authors)

  10. Hydrins, hydroosmotic neurohypophysial peptides: osmoregulatory adaptation in amphibians through vasotocin precursor processing.

    OpenAIRE

    Rouillé, Y; Michel, G; Chauvet, M T; Chauvet, J; Acher, R

    1989-01-01

    From neurointermediate pituitary glands of Xenopus laevis and Rana esculenta, previously unreported peptides termed hydrins, active on water permeability of frog urinary bladder and frog skin (Brunn or "water-balance" effect), have been isolated and sequenced. These peptides seem to be derived from the pro-vasotocin-neurophysin precursor. Hydrin 1, found in Xenopus, has been identified as vasotocin C-terminally extended with the Gly-Lys-Arg sequence; hydrin 2, found in Rana, has been identifi...

  11. Salida de campo a la laguna de La Nava (Fuentes de Nava, Palencia) el 28 de marzo de 1953

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a la laguna de La Nava, en Fuentes de Nava (Palencia), el 28 de marzo de 1953, de la que se anotaron observaciones sobre los siguientes anifibios: Epidalea calamita (Sapo corredor, llamado Bufo calamita por el autor), Pelobates cultripes (Sapo de espuelas) y Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por el autor), el reptil Podarcis muralis (Lagartija roquera, llamada Lacerta muralis por el autor), los siguientes mamíferos: Apodem...

  12. Salida de campo por Valladolid el 26 de febrero de 1953

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo por Valladolid capital, recorriendo el Sotillo y la Huerta del Rey, a orillas del río Pisuerga, el 26 de febrero de 1953, de la que se anotaron observaciones sobre una camisa de Malpolon monspessulanus (Culebra bastarda, llamada Coleopeltis mouspessulanus por el autor), los siguientes anfibios: Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por el autor) y Triturus marmoratus (Tritón jaspeado, llamado Molge marmorata por el autor), lo...

  13. Juvenile frogs compensate for small metamorph size with terrestrial growth: Overcoming the effects of larval density and insecticide exposure

    Science.gov (United States)

    Boone, M.D.

    2005-01-01

    I reared four species of anurans (Rana sphenocephala [Southern Leopard Frog], Rana blairi [Plains Leopard Frog], Rana clamitans [Green Frog], and Bufo woodhousii [Woodhouse's Toad]) for seven to 12 months in small, outdoor terrestrial enclosures (1 x 2 m) to examine the consequences of larval competition (via density) and contaminant exposure (via the insecticide carbaryl). I added six Rana clamitans, eight Rana sphenocephala, eight Rana blairi, and 10 Bufo woodhousii to terrestrial enclosures shortly after metamorphosis and recaptured them during the following spring. All anurans from low-density ponds were significantly larger than those from high-density ponds, but these size differences did not significantly affect survival to or size at spring emergence. However, R. sphenocephala, R. blairi, and R. clamitans that survived to spring had been larger at metamorphosis on average than those that did not survive; in contrast, B. woodhousii that survived the winter were smaller at metamorphosis on average than those that did not survive. Carbaryl exposure affected mass at metamorphosis of R. clamitans and B. woodhousii that were added to enclosures, but this difference disappeared or did not increase by spring emergence. Overall, exposure to carbaryl during the larval period did not have any apparent effects on survival or growth during the terrestrial phase. In my study, anurans were able to offset small size at metamorphosis with terrestrial growth, although there was a trend of reduced overwinter survival for ranid species that metamorphosed at a smaller size. Copyright 2005 Society for the Study of Amphibians and Reptiles.

  14. Nuevas localidades y descripción del hábitat de la rana Lithobates johni, especie endémica en peligro de extinción New records and description of the habitat for the endangered endemic frog Lithobates johni

    Directory of Open Access Journals (Sweden)

    José Ismael Campos-Rodríguez

    2012-06-01

    Full Text Available Se dan a conocer 2 localidades nuevas para Lithobates johni en el estado de Puebla, ubicadas dentro de la porción alta de la cuenca del río Tecolutla. Adicionalmente se describen las características de calidad del agua y microhábitat de las nuevas localidades de la especie.In this paper we provide 2 new records of the endemic frog Lithobates johni from the Mexican State of Puebla. These records are within the Upper Basin of Rio Tecolutla. Additionally, we describe the water quality and microhabitat of the new localities for this species.

  15. Uso del microhábitat por hembras grávidas de la rana de hojarasca Craugastor loki en la selva alta perennifolia de Los Tuxtlas, Veracruz, México Microhabitat use by the leaf litter frog Craugastor loki gravid females in the tropical rainforest at Los Tuxtlas, Veracruz, Mexico

    Directory of Open Access Journals (Sweden)

    José Nicolás Urbina-Cardona

    2009-08-01

    Full Text Available Craugastor loki es la especie de anfibio más abundante en la selva alta perennifolia de Los Tuxtlas, registrándose 1 251 individuos (58% adultos durante un año de muestreo a lo largo de gran variedad de microhábitats en 6 fragmentos de selva. A pesar de que C. loki se considera una especie tolerante a la modificación del hábitat, el 71% de las hembras grávidas se encontraron en las áreas mejor conservadas. Hubo un mayor registro de hembras grávidas en el fragmento de selva continuo (473 ha, prefiriendo hábitats con una distancia mayor a 50 m del borde y suelos con cobertura y espesor de hojarasca altas, cobertura herbácea alta, humedad relativa alta, pero independientes de la distancia a los cuerpos de agua. En el presente estudio se demuestra que las hembras grávidas, un eslabón crítico para el mantenimiento de la especie, son vulnerables a la perdida de hábitat y efectos de borde. Un cambio en las zonas conservadas pudiera afectar la abundancia y estructura poblacional de C. loki, generando a futuro una peligrosa disrupción en la cadena trófica y en la estructura de las comunidades de la selva.Craugastor loki is the dominant amphibian in the Los Tuxtlas tropical rainforest. We recorded 1 251 individuals (58% adults in a sampling year within a great variety of microhabitats in 6 forest fragments. Although C. loki is considered tolerant to habitat disturbance, 71% of all gravid females were found in most highly conserved sites. Gravid females were mostly found in the largest forest fragment with continuous rainforest (473 ha, preferring habitats with distances to the edge over 50 m, soils with high leaf litter cover and depth, high understory density, high relative humidity but independent of the distance to water bodies. Gravid females, a critical element to maintain the species, are very vulnerable to habitat loss and edge effects. A change in conserved habitats may affect C. loki abundance and population structure, potentially seriously disrupting the trophic chains and community structure of the rainforest.

  16. Uso del microhábitat por hembras grávidas de la rana de hojarasca Craugastor loki en la selva alta perennifolia de Los Tuxtlas, Veracruz, México Microhabitat use by the leaf litter frog Craugastor loki gravid females in the tropical rainforest at Los Tuxtlas, Veracruz, Mexico

    OpenAIRE

    José Nicolás Urbina-Cardona; Víctor Hugo Reynoso

    2009-01-01

    Craugastor loki es la especie de anfibio más abundante en la selva alta perennifolia de Los Tuxtlas, registrándose 1 251 individuos (58% adultos) durante un año de muestreo a lo largo de gran variedad de microhábitats en 6 fragmentos de selva. A pesar de que C. loki se considera una especie tolerante a la modificación del hábitat, el 71% de las hembras grávidas se encontraron en las áreas mejor conservadas. Hubo un mayor registro de hembras grávidas en el fragmento de selva continuo (473 ha),...

  17. 虎纹蛙蝌蚪与幼蛙肌肉蛋白质的双向电泳图谱对比分析%Comparison and Analysis of the Two-dimensional Electrophoresis Patterns Between Rana Rugulosa Tadpole and Larval Froggy Sarcous Protein

    Institute of Scientific and Technical Information of China (English)

    虞鹏程; 廖东江; 简少卿

    2005-01-01

    双向电泳技术是蛋白质组研究的核心技术之一,通过对虎纹蛙蝌蚪与幼蛙的肌肉进行双向电泳并对其图谱对比分析,为其今后进行蛋白质组学的研究打下基础.

  18. 虎纹蛙和大树蛙肾细胞超微结构及其与环境适应性的关系%ULTRASTRUCTURES OF THE RENAL CELLS OF RANA RUGULOSA AND POLYPEDATES DENNYSI AND THE RELATION TO THEIR HABITATS

    Institute of Scientific and Technical Information of China (English)

    潘鸿春; 吴孝兵

    2002-01-01

    用透射电镜比较了大树蛙和虎纹蛙肾细胞的超微结构.大树蛙近曲小管上皮细胞具发达的质膜内褶迷路,虎纹蛙近曲小管上皮细胞无此结构;大树蛙远曲小管上皮细胞含丰富的质膜内褶,虎纹蛙远曲小管上皮细胞的质膜内褶较少;两种蛙的集合管上皮细胞都有质膜内褶迷路.结果表明,虎纹蛙和大树蛙之间肾细胞超微结构特征的差异是与它们不同的栖息环境和生态习性相适应的.图版1参13

  19. Prevalence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis) at Buenos Aires National Wildlife Refuge, Arizona, USA

    Science.gov (United States)

    Sigafus, Brent H.; Hossack, Blake R.; Muths, Erin L.; Schwalbe, Cecil R.

    2014-01-01

    Information on disease presence can be of use to natural resource managers, especially in areas supporting threatened and endangered species that occur coincidentally with species that are suspected vectors for disease. Ad hoc reports may be of limited utility (Muths et al. 2009), but a general sense of pathogen presence (or absence) can inform management directed at T&E species, especially in regions where disease is suspected to have caused population declines (Bradley et al. 2002). The Chiricahua Leopard Frog (Lithobates chiricahuensis), a species susceptible to infection by the amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) (Bradley et al. 2002), and the non-native, invasive American Bullfrog (L. catesbeianus), a suspected vector for chytridiomycosis (Schloegel et al. 2012, Gervasi et al. 2013), both occur at Buenos Aires National Wildlife Refuge (BANWR) and surrounding lands in southern Arizona. Efforts to eradicate the bullfrog from BANWR began in 1997 (Suhre, 2010). Eradication from the southern portion of BANWR was successful by 2008 but the bullfrog remains present at the Arivaca Cienega and in areas immediately adjacent to the refuge (Fig. 1). Curtailing the re-invasion of the bullfrog into BANWR will require vigilance as to ensure the health of Chiricahua Leopard Frog populations.

  20. Final report on effects of environmental radiation of Kori nuclear power plant on human population

    International Nuclear Information System (INIS)

    In order to clarify and protect the effects of environmental radiation according to the operation of Kori nuclear power plant on the human population, the base line survey for the human monitoring, human life habits, expected individual exposure dose, frequencies of chromosomal aberration, gene frequencies and karyotypes in amphibia, fauna, and radiation sensitivities in microorganisms which have been living around the power plant site were carried out. Kilchonri population which took for the human monitoring lie within a 2 km distance from the power plant site. Human monitoring, house and food characteristics, individual experience of x-ray exposures, human chromosome analysis and fauna were surveyed and expressed in numerical tables. Chromosome number obtained from the amphibia which were collected around the power plant area was as follows: Kaloula borealis 2N=30, Rana amurensis 2N=26, Rana dybouskii 2N=24, Rana rugosa 2N=26, Rana nigromaculata 2N=26, Rana plancyi 2N=26, Bombina orientalis 2N=24, Hyla arborea 2N=24, Bufo stejnegeri 2N=22, Bufo bufo 2N=22. (author)

  1. Effects of environmental radiation of Kori nuclear power plant on the human population

    International Nuclear Information System (INIS)

    In order to clarify and protect the effects of environmental radiation according to the operation of Kori nuclear power plant on human population, the base line survey for the human monitoring, the fauna of land nocturnal insects, and the karyotypes of amphibian species which have been living around the power plant site were carried out. ''Kilchunri'' population which took for the human monitoring lie within a 2km distance from power plant site. Human monitoring, house and food characteristics, individual experience of X-ray exposures, human chromosome analysis and fauna of nocturnal land insects were surveyed and expressed in numerical tables. Chromosome number obtained from the amphibia which were collected around the power plant area was as follows; Kaloula borealis 2N=30, Rana amurensis 2N=26, Rana dybouskii 2N=24, Rana rugosa 2N=26, Rana migromaculata 2N=26, Rana plancyi 2N=26, Bombina orientalis 2N=24, Hyla arborea 2N=24, Bufo stejnegeri 2N=22, and Bufo bufo 2N=22. (author)

  2. Nomenclatural notes on living and fossil amphibians

    Directory of Open Access Journals (Sweden)

    Martín, C.

    2012-06-01

    Full Text Available A review of extinct and living amphibians known from fossils (Allocaudata, Anura and Caudata has revealed several cases that require nomenclatural changes in order to stabilize the taxonomy of the group. Nomenclatural changes include homonym replacements, corrections of spelling variants and authorships, name availabilities, and in particular, the proposal of new combinations. These changes will allow the incorporation of some palaeontological taxa to the current evolutionary models of relationship of modern forms based on molecular phylogenies. Rana cadurcorum for Rana plicata Filhol, 1877, Rana auscitana for Rana pygmaea Lartet, 1851, and Rana sendoa for Rana robusta Brunner, 1956. Anchylorana Taylor, 1942 is considered a new synonym of Lithobates Fitzinger, 1843. New combinations proposed are: Anaxyrus defensor for Bufo defensor Meylan, 2005; Anaxyrus hibbardi for Bufo hibbardi Taylor, 1937; Anaxyrus pliocompactilis for Bufo pliocompactilis Wilson, 1968; Anaxyrus repentinus for Bufo repentinus Tihen, 1962; Anaxyrus rexroadensis for Bufo rexroadensis Tihen, 1962; Anaxyrus spongifrons for Bufo spongifrons Tihen, 1962; Anaxyrus suspectus for Bufo suspectus Tihen, 1962; Anaxyrus tiheni for Bufo tiheni Auffenberg, 1957; Anaxyrus valentinensis for Bufo valentinensis Estes et Tihen, 1964; Ichthyosaura wintershofi for Triturus wintershofi Lunau, 1950; Incilius praevius for Bufo praevius Tihen, 1951; Lithobates bucella for Rana bucella Holman, 1965; Lithobates dubitus for Anchylorana dubita Taylor, 1942; Lithobates fayeae for Rana fayeae Taylor, 1942; Lithobates miocenicus for Rana miocenica Holman, 1965; Lithobates moorei for Anchylorana moorei Taylor, 1942; Lithobates parvissimus for Rana parvissima

  3. Rediscovery of Pelobates fuscus insubricus in the Asti Province, north-western Italy

    Directory of Open Access Journals (Sweden)

    Vincenzo Mercurio

    2007-01-01

    Full Text Available The amphibians of the pond complex “Stagni di Belangero” in the Po Plain, Asti Province, have been studied. The species living in the pond are Bufo bufo, Bufo viridis, Hyla intermedia, Pelobates fuscus, Rana dalmatina, Rana synklepton esculenta, Rana cf. kurtmuelleri, Triturus carnifex and Triturus vulgaris. Species composition, migration period of P. fuscus, and biometric data are provided. Relevant importance has been given to P. fuscus, since we reconfirm its presence in one of the ponds 13 years after its first finding in the area. This toad is also one of the most threatened species of amphibians in Europe and needs particular attention in order to be protected adequately.

  4. Salida de campo a la laguna de La Nava (Fuentes de Nava, Palencia) los días 1, 2 y 3 de noviembre de 1952

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a la laguna de La Nava, en Fuentes de Nava, recorriendo también Grijota y Villamartín de Campos, en la provincia de Palencia, los días 1, 2 y 3 de noviembre de 1952, de la que se anotaron observaciones sobre el pez Carassius sp. (Pez rojo), el reptil Natrix maura (Culebra viperina, llamada Tropidonotus viperinus por el autor), los siguientes anfibios: Pelobates cultripes (Sapo de espuelas) y Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibun...

  5. Salida de campo a la laguna de La Nava (Fuentes de Nava, Palencia) el 27 y 28 de julio de 1952

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a la laguna de La Nava, en Fuentes de Nava, recorriendo también Grijota y Villamartín de Campos, en la provincia de Palencia, el 27 y 28 de julio de 1952, de la que se anotaron observaciones sobre los siguientes anfibios: Epidalea calamita (Sapo corredor, llamado Bufo calamita por el autor), Pelobates cultripes (Sapo de espuelas), Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por el autor) y Pleurodeles waltl (Gallipato, también llam...

  6. Salida de campo a Cabezón de Pisuerga (Valladolid) el 10 de junio de 1953

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a Cabezón de Pisuerga (Valladolid) el 10 de junio de 1953, de la que se anotaron observaciones sobre insectos: el miriápodo Julus, grillos y saltamontes (sin identificar las especies), el anfibio Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por el autor), los siguientes mamíferos: Lirón (pudiendo ser Eliomys quercinus o Glis glis) y Oryctolagus cuniculus (Conejo), y las siguientes especies: Alectoris sp. (Perdiz), Anthus campestris (...

  7. Salida de campo a Laguna de Duero (Valladolid) el 19 de mayo de 1952

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a Laguna de Duero, en Valladolid, el 19 de mayo de 1952, de la que se anotaron observaciones sobre anidamiento, cría y alimentación de Ciconia ciconia (Cigüeña blanca). Se analizaron los contenidos estomacales de tres pollos, en los que aparecieron, entre insectos y otros elementos, los siguientes herpetos: Natrix maura (Culebra viperina, llamada Tropidonotus viperinus por el autor), Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por e...

  8. Salida de campo a Ribera del Cubo (o Torre Duero, en Torrecilla de Abadesa, Valladolid) el 21 y 22 de junio de 1953

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a Ribera del Cubo (seguramente, sinónimo de Torre Duero, que se halla en la localidad de Torrecilla de Abadesa, Valladolid) los días 21 y 22 de junio de 1953, de la que se anotaron observaciones sobre insectos de la familia Acrididae (orden Orthoptera), los siguientes peces: Barbus sp. (Barbo) y Carassius auratus (Pez rojo), el anfibio Pelophylax esculentus (Rana verde europea, llamada Rana sculenta o R.esculenta ridibunda por el autor), los siguientes reptiles: Lagartos y lag...

  9. Species Diversity and Distribution of Amphibians and Reptiles in Nature Park "Sinite Kamani" in Stara Planina Mt. (Bulgaria

    Directory of Open Access Journals (Sweden)

    Stanimira R. Deleva

    2014-12-01

    Full Text Available The current study presents briefly the species composition and distribution of the amphibians and reptiles in the Nature Park "Sinite Kamani" in Stara Planina Mnt. Bulgaria, based on a 2×2 km UTM grid. Between 2012 and 2014, we identified total 20 species (7 amphibians and 13 reptiles. We documented three new amphibian species for the region (Hyla arborea, Rana dalmatina and Rana graeca, which is discovered for the area for the first time and three species of reptiles (Testudo hermanni, Ablepharus kitaibelii and Lacerta trilienata. The contemporary conservation status for each species is presented and conservation threats and problems, specific for the park are discussed.

  10. Electrophoretic pattern of blood serum proteins of some of the vertebrates of Pakistan

    International Nuclear Information System (INIS)

    The electrophoretic pattern of blood serum proteins of some of the common fishes e.g. Catla catla, Cirrhina mrigala, Channa punctatus, Channa marulius, Wallago attu, Heterop-neustes fossilis; amphibia e.g., Rana tigrina, Rana cyanophlyctis, Bufo melanostictus; reptiles e.g. Varanus bengalensis, Uromastix hardwickii; birds e.g. Columba livia, Gallus domesticus, Passer domestica, Anas platyrhynchos; and mammals e.g. Homo sapiens, Mus musculus, Lepus cuniculus have been described. The mobility of proteins of blood sera has been studied over cellulose acetate paper and then a comparative pattern analysed

  11. Primer Reporte de Huevos de Mosca de la Carne (Diptera: Sarcophagidae) en Pristimantis achatinus (Anura: Craugastoridae) de Colombia -resumen-

    OpenAIRE

    Sebastian Escobar-Vargas; Mateo Marín-Martínez; Juan C Zuluaga-Izasa

    2014-01-01

    En el marco de un proyecto para el estudio de la microflora bacteriana gramnegativa asociada a la cloaca de ranas de la especie Pristimantis achatinus‚ se hizo el hallazgo de huevos de individuos de la familia Sarcophagidae (Díptera) depositados en la cloaca de una de las ranas. El material cloacal fue extraído con micropipetas de punta amarilla (10-100µL) y fue disuelto en caldo peptonado e incubado a 37°C durante 24 horas. Posteriormente‚ 0‚1mL de la muestra fueron sembrados por extensión e...

  12. Excitabilidad iterativa y actividad rítmica de los músculos estriados: contracción prosténica

    OpenAIRE

    Ordoñez, Hernando

    2011-01-01

    Se hace un estudio sobre la historia de la excitabilidad iterativa. Se relaciona la excitabilidad iterativa con la contracción prosténica. Se describen los caracteres de esta variedad de contracción muscular, a saber: contracción rítmica que aparece en el músculo gastrocnemio de varias clases de ranas, hyla labialis, rana esculenta, bufo marinus; excitación directa; la excitación repetida puede ser choques de inducción, descargas de condensadores, estimulación electrónica; la frecuencia de lo...

  13. Structure and transmembrane nature of the acetylcholine receptor in amphibian skeletal muscle as revealed by cross-reacting monoclonal antibodies

    OpenAIRE

    1984-01-01

    A collection of 126 monoclonal antibodies (mAbs) made against acetylcholine receptors (AChRs) from the electric organs of Torpedo californica or Electrophorus electricus was tested for cross-reactivity with AChRs in cryostat sections of skeletal muscle from Rana pipiens and Xenopus laevis by indirect immunofluorescence. 49 mAbs (39%) cross- reacted with AChRs from Rana, and 25 mAbs (20%) cross-reacted with AChRs from Xenopus. mAbs specific for each of the four subunits of electric organ AChR ...

  14. Respuesta de los ensamblajes de anfibios y reptiles a los cambios en la cobertura del suelo, en localidades del departamento del Cesar-Colombia

    OpenAIRE

    Bernal-González, Vladimir Andrés

    2014-01-01

    Se determinó el efecto del cambio en la cobertura del suelo en localidades del departamento del Cesar, a través de la evaluación de la dinámica espacio-temporal de los ensamblajes de ranas, lagartos y serpientes y el análisis de la distribución de los grupos ecológicos de ranas, lagartos y serpientes en el paisaje rural de la cuenca del río Cesar, en la región Caribe de Colombia. Se realizaron cuatro salidas de campo entre diciembre de 2011 y diciembre de 2012, que abarcaron las ...

  15. Salida de campo a Santo Domingo de Silos, en Burgos, el 13 de septiembre de 1953

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a Santo Domingo de Silos, en Burgos, el 13 de septiembre de 1953, de la que se anotaron observaciones sobre los siguientes anfibios: Alytes sp. (Sapo partero), Bufo bufo (Sapo común, llamado B.vulgaris por el autor), Hyla sp. (Ranita), Lissotriton vulgaris, Rana sp. (Rana), Salamandra salamandra (Salamandra común, también llamada S.maculosa por el autor) y Triturus cristatus (Tritón crestado), los siguientes reptiles: Acanthodactylus erythrurus (Lagartija colirroja, llamada A....

  16. Salida de campo a Montejo de la Sierra (Madrid) a mediados de septiembre de 1953

    OpenAIRE

    Valverde Gómez, José Antonio, 1926-2003

    2008-01-01

    Salida de campo a Montejo de la Sierra, en Madrid, a mediados de septiembre de 1953, de la que se anotaron observaciones sobre los siguientes anfibios: Bufo bufo (Sapo común, llamado B.vulgaris por el autor) y Rana sp. (Rana), los siguientes reptiles: Natrix maura (Culebra viperina, llamada Tropidonotus viperinus por el autor) y Psammodromus sp. (Lagartija), los siguientes mamíferos: Arvicola sapidus (Rata de agua, también llamado Ratón aguadero), Martes foina (Garduña), Plecotus sp. (Orejudo...

  17. Ovid MEDLINE Instruction can be Evaluated Using a Validated Search Assessment Tool. A Review of: Rana, G. K., Bradley, D. R., Hamstra, S. J., Ross, P. T., Schumacher, R. E., Frohna, J. G., & Lypson, M. L. (2011. A validated search assessment tool: Assessing practice-based learning and improvement in a residency program. Journal of the Medical Library Association, 99(1, 77-81. doi:10.3163/1536-5050.99.1.013

    Directory of Open Access Journals (Sweden)

    Giovanna Badia

    2011-01-01

    Full Text Available Objective – To determine the construct validity of a search assessment instrument that is used to evaluate search strategies in Ovid MEDLINE. Design – Cross-sectional, cohort study. Setting – The Academic Medical Center of the University of Michigan. Subjects – All 22 first-year residents in the Department of Pediatrics in 2004 (cohort 1; 10 senior pediatric residents in 2005 (cohort 2; and 9 faculty members who taught evidence based medicine (EBM and published on EBM topics. Methods – Two methods were employed to determine whether the University of Michigan MEDLINE Search Assessment Instrument (UMMSA could show differences between searchers’ construction of a MEDLINE search strategy.The first method tested the search skills of all 22 incoming pediatrics residents (cohort 1 after they received MEDLINE training in 2004, and again upon graduation in 2007. Only 15 of these residents were tested upon graduation; seven were either no longer in the residency program, or had quickly left the institution after graduation. The search test asked study participants to read a clinical scenario, identify the search question in the scenario, and perform an Ovid MEDLINE search. Two librarians scored the blinded search strategies.The second method compared the scores of the 22 residents with the scores of ten senior residents (cohort 2 and nine faculty volunteers. Unlike the first cohort, the ten senior residents had not received any MEDLINE training. The faculty members’ search strategies were used as the gold standard comparison for scoring the search skills of the two cohorts.Main Results – The search strategy scores of the 22 first-year residents, who received training, improved from 2004 to 2007 (mean improvement: 51.7 to 78.7; t(14=5.43, PConclusion – According to the authors, “the results of this study provide evidence for the validity of an instrument to evaluate MEDLINE search strategies” (p. 81, since the instrument under investigation was able to measure improvements and differences in the search performances of the study’s participants. A validated search assessment instrument can effectively measure improvements in residents’ search skills to demonstrate training effectiveness, as well as satisfy practice-based learning competency requirements from the Accreditation Council for Graduate Medical Education.

  18. Developmental and Regional Patterns of GAP-43 Immunoreactivity in a Metamorphosing Brain

    OpenAIRE

    Simmons, Andrea Megela; Tanyu, Leslie H.; Horowitz, Seth S.; Chapman, Judith A.; Brown, Rebecca A.

    2008-01-01

    Growth-associated protein-43 is typically expressed at high levels in the nervous system during development. In adult animals, its expression is lower, but still observable in brain areas showing structural or functional plasticity. We examined patterns of GAP-43 immunoreactivity in the brain of the bullfrog, an animal whose nervous system undergoes considerable reorganization across metamorphic development and retains a strong capacity for plasticity in adulthood. Immunolabeling was mostly d...

  19. Damping Properties of the Hair Bundle

    OpenAIRE

    Baumgart, Johannes; Kozlov, Andrei S.; Risler, Thomas; Hudspeth, A. James

    2015-01-01

    The viscous liquid surrounding a hair bundle dissipates energy and dampens oscillations, which poses a fundamental physical challenge to the high sensitivity and sharp frequency selectivity of hearing. To identify the mechanical forces at play, we constructed a detailed finite-element model of the hair bundle. Based on data from the hair bundle of the bullfrog's sacculus, this model treats the interaction of stereocilia both with the surrounding liquid and with the liquid in the narrow gaps b...

  20. Chemical defense of the eastern newt (Notophthalmus viridescens: variation in efficiency against different consumers and in different habitats.

    Directory of Open Access Journals (Sweden)

    Zachary H Marion

    Full Text Available Amphibian secondary metabolites are well known chemically, but their ecological functions are poorly understood--even for well-studied species. For example, the eastern newt (Notophthalmus viridescens is a well known secretor of tetrodotoxin (TTX, with this compound hypothesized to facilitate this salamander's coexistence with a variety of aquatic consumers across the eastern United States. However, this assumption of chemical defense is primarily based on observational data with low replication against only a few predator types. Therefore, we tested the hypothesis that N. viridescens is chemically defended against co-occurring fishes, invertebrates, and amphibian generalist predators and that this defense confers high survivorship when newts are transplanted into both fish-containing and fishless habitats. We found that adult eastern newts were unpalatable to predatory fishes (Micropterus salmoides, Lepomis macrochirus and a crayfish (Procambarus clarkii, but were readily consumed by bullfrogs (Lithobates catesbeianus. The eggs and neonate larvae were also unpalatable to fish (L. macrochirus. Bioassay-guided fractionation confirmed that deterrence is chemical and that ecologically relevant concentrations of TTX would deter feeding. Despite predatory fishes rejecting eastern newts in laboratory assays, field experiments demonstrated that tethered newts suffered high rates of predation in fish-containing ponds. We suggest that this may be due to predation by amphibians (frogs and reptiles (turtles that co-occur with fishes rather than from fishes directly. Fishes suppress invertebrate consumers that prey on bullfrog larvae, leading to higher bullfrog densities in fish containing ponds and thus considerable consumption of newts due to bullfrog tolerance of newt chemical defenses. Amphibian chemical defenses, and consumer responses to them, may be more complex and indirect than previously appreciated.