• Applied Microscopy
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• v.40 no.2
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• pp.81-88
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• 2010

The fine structural characteristics of the apoptotic cells in the cutaneous epithelium of the anuran tadpole of the black-spotted frog, Rana nigromaculata was examined using the TUNEL (Terminal deoxynucleotidyl transferase-mediated biotinylated d-Uridine triphosphate Nick End Labeling) staining technique and TEM (transmission electron microscopy) observations. The cutaneous epithelium of the tadpole was composed of stratified cuboidal cells and the apoptotic cell death was observed continuously during the tail degeneration stages from the Shumway stage number 31 to 33. The early apoptotic cells shown in the epithelium demonstrated condensation and margination of the chromatin material at the nuclear periphery, and nuclear breakdown and cytoplasmic condensation were followed. Subsequent cytoplasmic degeneration of the apoptotic cell were produced by membrane-bounded cell fragments with relatively well preserved organelles. Following the processes of autophagic degradation, the late apoptotic cells being phagocytosed by other surrounding cells. These nearby cells, presumptive intraepithelial macrophages, contain a variety of lysosomal residual bodies which fuses with other cell organelles or other cytoplasmatic material to form secondary lysosomes. They are soon transformed into lamellar shaped vesicles and finally disappeared during the process of degradation.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.121-126
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• 2007

We monitored gold-spotted pond frog (Rana chosenica) populations near the Korea National University of Education in Chungbuk, Korea, from 19 May to 8 August, 2006 to examine the spatial distribution of populations in local areas and to investigate patterns of migration of adult gold-spotted pond frogs from terrestrial hibernation sites to breeding sites, We captured individuals from the largest population using a drift fence with 22 pitfall traps surrounding the breeding site. A total of 22 individuals (19 males and 3 females) were captured between 23 May and 15 June. No peak in breeding migration was detected, but the onset of the breeding migration may correspond with increased humidity. Male body weights were negatively correlated with sampling dates. Seven of 22 individuals were captured at the 4th pitfall trap, which was placed between two culverts. The capture rate per pitfall trap was higher in traps close to the rice field banks (1.44, traps $1{\sim}9$) than in traps facing hilly land (0.33, traps $13{\sim}18$). Comparative data from the Korean frog (Rana coreana), a sympatric species in the study area, were also collected and compared with those of the gold-spotted pond frog.

• The Korean Journal of Ecology
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• v.25 no.1
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• pp.25-28
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• 2002

The advertisement call of anurans functions to attract potential mates. The dominant frequency of an advertisement call is generally getting lower with increased snout-vent length (SVL) of the caller Rana rugosa has an advertisement call tilth a particularly high frequency modulation. We conducted a playback experiment to verify the function of frequency modulation, and investigated the territorial behavior of the frog. The frog has five types of territory defense strategy. Strategy choice depended on the caller's SVL. Small males became satellites or lowered the dominant frequency of their advertisement call, whereas large males actively defended their territory with encounter calls. In response to high frequency (1107 Hz) playback, the frogs lowered their advertisement call frequency, and towered them further in response to the low frequency (1028 Hz) playback. In addition, the number of pulses in a call was increased in response to the playback. These results indicate that the frog avoids physical conflict with competitors by selecting a territory defense strategy suitable for the caller's size, and by lowering its call frequency to disguise its SVL.

• Mycobiology
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• v.36 no.1
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• pp.10-12
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• 2008

In recent years, there has been a rapid decrease in amphibian populations worldwide, and infectious diseases have been associated with this decline. Diseased frogs inhabiting Korea were collected from fields, and the diseases were identified by morphological and molecular analyses. Two fungal diseases-saprolegniasis and chromomycosis-were detected in the frogs. Saprolegniasis caused by Saprolegnia spp. was found in Rana plancyi chosenica from Gangwon-do and Rana huanrenensis from Chungbuk. Chromomycosis, which is caused by infection with Cladosporium cladosporioides, was detected in Rana catesbeiana from Busan.

• Animal cells and systems
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• v.7 no.2
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• pp.165-168
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• 2003

The present studies investigate the induced effects of two pesticides lambda cyhalothrin (pyrethroid) and monocrotophos (organophosphate) on Rana cyanophlyctis (common skittering frog). Two different concentrations i.e. 0.1 and 1％ were used and cholinesterase activity was observed in liver, kidney and brain of these frogs. It was decreased upto 34.6 and 46.3％ in liver, 25.08 and 57.1％ in kidney and 31.64 and 50.7％ in brain under the effect of lambda cyhalothrin. In the case of monocrotophos treatment, cholinesterase decreased upto 37.7 and 57.7％ in liver,57.5 and 67.5％ in kidney and 47.6 and 65.9％ in brain, respectively.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.110-113
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• 2009

In recent years, there has been a rapid global decline in amphibian populations, and infectious diseases have been associated with this decline. Diseased Gold-spotted pond frogs (Rana plancyi chosenica) were collected from a frog farm in Korea and identified using morphological and molecular analysis to identify the disease. The typical symptoms of ranaviral infection were observed in the tadpoles and adults frogs. The nucleotide sequence analysis revealed that the sequences showed the closest similarity with sequences to Frog virus 3, which belongs to the genus Ranavirus.

• Korean Journal of Environmental Biology
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• v.18 no.1
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• pp.113-120
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• 2000

Herpetofauna biodiversity was surveyed at the Chin-do. The results are as follows: During census periods presence of 2 orders, 4 families, 6 species of amphibians and 1 order, 2 suborders, 4 families, 8 species of reptiles were observed or found indirectly by auditorial recording from residents at the Chin-do. Among them 1 protected wildlife(Agkistrodon saxatilis) and several rare species such as Takydromus wolteri, Sciucella laterale laterale and Zamenis spinalis were indentified. Rana nigromaculata and Rana catesbeiana were found in all surveyed areas. Dominant amphibian species was Rana rugosa (D'= 25.8%) and reptile was Takydromus wolteri (D'= 21.8%). Among 4 areas survey area, Uisin-myon showed the highest level of species richness, diversity, and evenness indices (R'= 2.393, H'= 1.931, and E'= 0.7772, respectively). The species richness of Kunnae-myon was lower (R'= 0.932) than other surveyed regions. Based on the frequency of occurrence (85.71%), habitation density of Rana catesbeiana was very common in Chin-do, suggesting that spreading of this foreign species in the entire Korean peninsula. Scincella laterale laterale, Elaphe dione, Elaphe rufodorsata, Dinodon rufozonatus rufozonatus, Rhabdophis tigrinus tigrinus, Agkistrodon ussuriensis, and Zamenis spinalis showed low frequency of occurrence ( < 10%) and efforts to protect them are required. [Herpetofauna, Bio-diversity, Chin-Do].

• Journal of Environmental Impact Assessment
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• v.24 no.2
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• pp.175-189
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• 2015

The objective of this study was to analyze characteristics of distribution of amphibian species and the affecting ecological factors. For the study, habitat environment factors were determined and applied to a habitat suitability model for the data collected from the Seom River in Hoengseong County and Wonju City, Gangwon Province, Korea between March 2013 to October 2013. The analyzed amphibian species were Rana nigromaculata, Hyla japonica, Rana dybowski, and Rana rugosa Temminck and Schlegel, and a logistic regression model was used with the pseudo-absence data. The result of the model analysis suggests that the major factors for Rana nigromaculata are distance to vegetation and rock and that for Hyla japonica is waterway. Rana dybowski and Rana rugosa Temminck and Schlegel have similar habitat characteristics, but the latter is shown to be dominant due to its wider habitat preference. According to the species richness model, the analyzed amphibian species are shown to have tendency to move between valleys or streams. This study quantitatively analyzed habitat environment characteristics using species distribution model, however, there is a limitation in terms of analysis on food factor and connectivity with other species. Combined with additional density or habitat analysis on birds or fish, this study can lead to more comprehensive analysis on biological environment factors.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.266-272
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• 1996

Experiments were carried out to ascertain whether gonadotropin or a phorbol ester (12-O-tetradecanoyl phorbol-13-acetate, TPA) induces oocyte ovulation and stimulates prostaglandin synthesis by Rana ovarian follicles in vitro. Rana nigromaculata collected from underground in spring were utilized for the present experiment. Treatment of frog pituitary homogenate (FPH) or TPA to ovarian fragments in culture induced oocyte ovulation in a dose dependent manner and stimulated prostaglandin F2a (PGF$_2$$\alpha$ synthesis. Both treatruents were more effective in inducing the ovulation and PGF$_2$$\alpha$ secretion by the follicles obtained in May than those in April. A Protein kinase C inactivator, 1-(5-isoquinolinyl-sulfonyl)-2-methyl-piperazine (H-7), or cyclooxygenase inhibitor, indomethacin (IM) suppressed the FPH- or TPA-induced PGF$_2$$\alpha$ production, but IM failed to suppress the FPH- or TPA-induced ovulation. Time course of oocyte ovulation and PGF$_2$$\alpha$ secretion by FPH and TPA treatments were very similar to each other. FPH stimulated progesterone secretion by the follicle but TPA failed to do so. Taken together, the data presented here suggest that protein kinase C (PKC) in follicle play a role in the ovulation process of Rana nigromaculata, probably via prostaglandin synthesis.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.203-207
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• 2003

Amphibian biodiversity, community structure and habitats were surveyed in the Mt. Myungji area from April 2002 to March 2003. During the survey period 2orders, 4 families, 7 species of amphibians were observed. Bombina orientalis (DI =45.1%) was dominant and Bufo stejnegeri (DI = 12.8%), Rana rugosa and Rana dybowskii (DI = 9.9% each) Rana nigromaculata and Rana huanrenensis (DI 1.4% each), and Onycodactylus fisheri (DI = 7.0%) followed. Frequency of occurrence of O. fisheri and B. stejnegeri was largely different according to the altitude and human residence in their habitats.R. nigromaculata and R. huanrenensis showed low frequency of occurrence (<10%) suggesting the decrease in habitation density in this area. The species richness (R'), general diversity (H'), and evenness (E') of amphibians in this area were 0.98, 2.12, and 0.76, respectively, suggesting relatively healthy condition of amphibian community in this area.