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Colonization and Extinction Patterns of a Metapopulation of Gold-spotted Pond Frogs, Rana plancyi chosenica  [cached]
Park, Daesik,Shi-Ryong Park,Ha-Cheol Sung
Journal of Ecology and Field Biology , 2009,
Abstract: We investigated colonization and extinction patterns in a metapopulation of the gold-spotted pondfrog (Rana plancyi chosenica) near the Korea National University of Education, Chungbuk, Korea, by surveyingthe frogs in the nine occupied habitat patches in the study area four times per breeding season for three years(2006~2008) and recording whether the patches were occupied by frogs as well as how many frogs were callingin the patches. We then developed five a priori year-specific models using the Akaike Information Criterion (AIC).The models predicted that: 1) probabilities of colonization and local extinction of the frogs were better explainedby year-dependent models than by constant models, 2) there are high local extinction and low colonizationprobabilities, 3) approximately 31% number of patches will be occupied at equilibrium, and 4) that considerablevariation in occupation rate should occur over a 30-year period, due to demographic stochasticity (in our model,the occupation rate ranged from 0.222 to 0.889). Our results suggest that colonization is important in thismetapopulation system, which is governed by mainly stochastic components, and that more constructiveconservation effects are needed to increase local colonization rates.
Monitoring Local Populations and Breeding Migration Patterns of the Gold-spotted Pond Frog, Rana chosenica  [cached]
Sung, Ha-Cheol,Sangmin Cha,Seokwan Cheong,Daesik Park
Journal of Ecology and Field Biology , 2007,
Abstract: We monitored gold-spotted pond frog (Rana chosenica) populations near the Korea NationalUniversity of Education in Chungbuk, Korea, from 19 May to 8 August, 2006 to examine the spatial distributionof populations in local areas and to investigate patterns of migration of adult gold-spotted pond frogs fromterrestrial hibernation sites to breeding sites, We captured individuals from the largest population using a driftfence with 22 pitfall traps surrounding the breeding site. A total of 22 individuals (19 males and 3 females) werecaptured between 23 May and 15 June. No peak in breeding migration was detected, but the onset of thebreeding migration may correspond with increased humidity. Male body weights were negatively correlated withsampling dates. Seven of 22 individuals were captured at the 4th pitfall trap, which was placed between twoculverts. The capture rate per pitfall trap was higher in traps close to the rice field banks (1.44, traps 1~9) thanin traps facing hilly land (0.33, traps 13~18). Comparative data from the Korean frog (Rana coreana), asympatric species in the study area, were also collected and compared with those of the gold-spotted pond frog.
An immunohistochemical study of the pancreatic endocrine cells of the Korean golden frog, Rana plancyi chosenica  [cached]
H.S. Lee,J.H. Chang,S.K. Ku
European Journal of Histochemistry , 2012, DOI: 10.4081/ejh.2012.e5
Abstract: The regional distribution and quantitative frequency of pancreatic endocrine cells were demonstrated in the Korean golden frog (Rana plancyi chosenica Okada), which is known as a Korean endemic species, for the first time, by immunohistochemical methods using specific mammalian antisera to insulin, glucagon, somatostatin and human pancreatic polypeptide (PP). In the pancreas of the Korean golden frog, all four endocrine cell types were demonstrated. Insulin- and glucagon-positive cells were located in the pancreas as single cells or islet-like clusters with frequencies of 85.90±18.28 and 54.30±8.77/1,000/1,000 cells, respectively. Somatostatin-containing cells were also dispersed in the pancreas as single cells or clusters but in the case of clusters, they are exclusively situated in the marginal regions of insulin- or glucagon-positive cell clusters. Cells stained for somatostatin cell frequency was 15.50±3.10/1000 cells. PP-containing cells were also distributed as single cells or clusters with frequency of 53.40±11.96/1,000 cells. Clusters consisted of PP-positive cells are distributed as a core type and a marginally distributed type. Overall, there were 40.84±3.81% insulin-, 26.02±1.71% glucagon-, 7.63±2.09% somatostatin- and 25.51±3.26% PP-IR cells.
Skeletochronological Age Determination and Comparative Demographic Analysis of Two Populations of the Gold-spotted Pond Frog (Rana chosenica)
Cheong, Seokwan,Daesik Park,Ha-Cheol Sung,Jung Hyun Lee
Journal of Ecology and Field Biology , 2007,
Abstract: To obtain demographic information on threatened gold-spotted pond frog (Rana chosenica Okada,1931) populations, we determined the ages of 45 male and 13 female frogs (20 males and 9 females fromCheongwon and 25 males and 4 females from Tae-an) and compared the age structures and growth patternsof the two populations in 2006. The snout-vent length (SVL) and body weight of female frogs were greater thanthose of male frogs in both populations. Male frogs’ ages ranged 2 to 7 years old and females’ ages ranged3 to 6 years old. In both populations, 4 years old male frogs were the most abundant age-sex class. The agestructures of the two populations were significantly different and the growth coefficients of male frogs from theCheongwon population were greater than those from the Tae-an population. The mean age of males from theTae-an population was higher than that from the Cheongwon population. However, the SVL and body weightsof male frogs were not different between two populations and there was no difference between the twopopulations in the mean male SVL at any age. The results could increase our understanding of the life-historyof this threatened frog and may be useful in conservation planning.
Adaptive changes of gastro-fntero-pancreatic system endocrine cells in the black-spotted pond frog Rana nigromaculata after fasting  [cached]
Hongzhen PAN, Honghong CHEN, Lianjiu ZHU, Yang LI, Changchun LI, Shengzhou ZHANG
Current Zoology , 2009,
Abstract: Changes in distribution density, morphology and secretory content of endocrine cells in the gastro-entero-pancreatic system of black-spotted frogs Rana nigromaculata before and after fasting were investigated using immunohistochemistry and antisera to six gut hormones. Six types of endocrine cells were detected in the digestive tract of Rana nigromaculata, including 5-hydroxytryptamine (5-HT), gastrin (GAS), somatostatin (SOM), glucagon (GLU), pancreatic polypeptide (PP) and vasoactive intestinal polypeptide (VIP) cells. After fasting, the density of 5-HT cells in the esophagus, cardia and fundus, GAS cells in fundus and pylorus, PP cells in the fundus decreased significantly(P <0.01), while SOM cells in the cardia, GLU cells in the rectum increased significantly (P <0.01). The cytoplasmic processes of 5-HT cells became shorter or not detectable. The secretory content of GAS cells reduced in the cardia. The positive immunostaining reaction in the perinuclear region of SOM cells in the cardia, fundus and pylorus became weaker, while the staining intensity in the periphery of these cells became stronger. VIP cells were not detectable in the whole digestive tract after fasting. Five types of endocrine cells were found in the pancreas of Rana nigromaculata, including 5-HT, GAS, SOM, GLU and PP cells. After fasting, the density of 5-HT cells decreased slightly (P >0.05), while SOM, GAS, GLU and PP cells increased significantly (P <0.01). Furthermore, the secretory content of GLU cells increased significantly. Considering their functionalities, our results indicate that the changes of GEP endocrine cells in Rana nigromaculata responded adaptively to starvation-induced stress [Current Zoology 55 (4):301–308, 2009].
Water frogs (Rana esculenta complex) in Serbia: Morphological data
Krizmani? I.I.
Archives of Biological Sciences , 2008, DOI: 10.2298/abs0803449k
Abstract: The main purpose of this paper was to estimate morphometric variability of the water frog (Rana synklepton esculenta complex) population in Serbia. Altogether, 396 water frogs were collected at 15 localities in Serbia and analyzed using principal components for 18 selected indices, in addition to which correspondent analyses were conducted for 30 qualitative external morphological traits. The results showed that the population samples were heterogeneous and included three separate forms (Rana ridibunda, Rana lessonae and Rana kl. esculenta). Significant interspecific differ-ences were found between R. ridibunda and R. lessonae, which are clearly distinct from each other. Rana kl. esculenta specimens were in an intermediate position between R. ridibunda and R. lessonae, with values more similar to the R. ridibunda parent species.
An Immunohistochemical Study on the Endocrine Cells in the Gastrointestinal Tract of the Frog, Rana ridibunda
MineYaman,Berrin Gen?er Tarak?,Ali Bayrakdar,Hatice Orsay
Journal of Animal and Veterinary Advances , 2012,
Abstract: The regional distribution and relative frequency of endocrine cells was studied immuohistochemically in the gastrointestinal tract of the frog, Rana ridibunda, using antisera against serotonin, somatostatin-14, cholecystokinin and vasoactive intestinal polypeptide. These immunoreactive cells were located in the gastric glands of stomach and in the intestinal epithelium with variable frequencies. They were spherical or spindle shaped. The regional distributions and relative frequencies of the endocrine cells in the gastrointestinal tract of the Rana ridibunda were resembled to those of the other anuran species.
Effect of Anti Bcterial Skin Secretion of “Rana ridibanda” Frog on Methycillin Resistant Staph Aureus  [PDF]
Mohammad Amin Abbasi,Nariman Mosaffa,Sodabe Taheri,Khosro Molla Jaafari
Cell Journal , 2007,
Abstract: The dorsal skin of the Iranian frog, Rana ridibanda, is associated with numerous prominent granular glands which extract their secretions in the response to stressor or invading pathogens .The secretions have broad spectrum antimicrobial effects. In this research the effect of antimicrobial skin secretions from Iranian frog (Rana ridibanda) has been examined against gram positive Methycillin Resistant Staph Aureus (MRSA), under sterile conditions. To show this effect, 1cm2 of frog skin was cultured in complete tissue culture medium containing RPMI, FBS and FUNGISON for the period of 10 days. Immediately after, MRSA was exposed to frog skin secretion (medium culture) and Vancomycin. The results showed that the frog skin secretions has significant antimicrobial effect against MRSA. The range of inhibition zone for MRSA was the same as (20mm) Vancomycin in DISK method. In Minimum Inhibitory Concentration method, for MRSA, the tube 1/8 was positive.
On possibility of use of lake frog (Rana ridibunda) as a raw material  [PDF]
Dinh Van Hai,Mukatova Marfuga Dyucembaevna,Skolkov Sergey Alekseevich
Vestnik of Astrakhan State Technical University. Series: Fishing Industry , 2013,
Abstract: 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.
Karyotype Diversity of Different Geographical Population of Rana limmocharis boie,Rana j. Japonica and Microhyla ornata
泽蛙、日本林蛙、饰纹姬蛙不同地理居群的核型多样性 Karyotype Diversity of Different Geographical Population of Rana limmocharis boie,Rana j. Japonica and Microhyla ornata

QIAN Xiao-wei,ZHU Mu-yuan,
钱晓薇
,朱睦元QIAN Xiao-wei,ZHU Mu-yuan

遗传 , 2000,
Abstract: The karyotypes of Rana limmocharis boie,Rana j.Japonica,and Microhyla ornata from Wenzhou were studied.The karyotypes of nine populations of Rana limmocharis boie,four populations of Rana j Japonica and three populations of Microhyla ornata from different geographical regions were compared The results demonstrated that the same species of different geographical populations have the same amount of chromosome and karyotypic formulae Rana limmocharis boie and Rana j Japonica have 2n=26,NF=52 and 5 8 karyotypic formulae Microhyla ornata has 2n=24,NF=48 and 6 6 karyotypic formulae But some dissimilarities were found among them First,the number and sequence of submetacentric chromosome were different among them,and then the secondary contriction (SC)or satellite (Sat)were also different It was showed that the chromosomes of same species of different geographical population have diversities Conservation of frog genetic diversity must be considered of not only the genetic diversity conservation of the total frog population but also that of every frog breed
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