Caryotypes de Rana temporaria (L.) et de Rana dalmatina (Bonaparte)

The karyotype of Rana temporaria is analysed from preparations of squashed tadpole epidermis, the karyotype of Rana dalmatina from preparations of squashed larval epidermis and adult tissues. For each of these two species, the 26 chromosomes of the karyotype have been divided in two groups according to their length. Inside these two groups, three morphological criteria — relative length, arm-ratio and presence of secondary constriction — permit the identification of each of the component parts. For Rana dalmatina, the analysis of the two meiotic divisions shows that the classification remains possible in two groups. There is no evidence of an heteromorphic pair of chromosomes in these two species. The studies on Rana temporaria and Rana dalmatina are compared to recent ones on other Ranidae.     

A study on hearing in frogs (Rana pipiens and Rana clamitans)

Zusammenfassung Die relative Reizschwellkurve für die Schallempfindung bei den Fröschen Rana clamitans und R. pipiens wurde in dem Frequenzbereich von 30–15000 Hz bestimmt. Die Kurve ist dieselbe für beide Geschlechter. Versuche zeigten, daß Schälle entweder inhibierend oder stimulierend auf die Atmungsbewegungen wirken können. Diese Wirkung wird nicht von der Frequenz oder der Intensität der Schälle bestimmt, sondern von dem physiologischen Zustand des Tieres.Die Latenzzeit zwischen Reiz und Effekt ist unabhängig von der Tonfrequenz, wird aber von den Intervallen zwischen aufeinanderfolgenden Reizen beeinflußt; sie wird kürzer, wenn die Intervalle verlängert werden.Dressurversuche mit 18 Tieren, unter Anwendung von Strafung durch elektrische Schläge und einem Dressurton von 300 Hz, ergaben positive Erfolge bei zwei Individuen von R. clamitans.

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Contribution No. 67 of the Department of Biology, Hamilton College, McMaster University, Hamilton, Ontario.     

The physiology of hibernation in Canadian leopard frogs (Rana pipiens) and bullfrogs (Rana catesbeiana)

Canadian northern leopard frogs (Rana pipiens) and bullfrogs (Rana catesbeiana) were acclimated to 3 degrees C and submerged in anoxic (0-5 mmHg) and normoxic (Po(2) approximately 158 mmHg) water. Periodic measurements of blood Po(2), Pco(2), and pH were made on samples taken anaerobically from subsets of each species. Blood plasma was analyzed for [Na(+)], [K(+)], [Cl(-)], [lactate], [glucose], total calcium, total magnesium, and osmolality. Blood hematocrit was determined, and plasma bicarbonate concentration was calculated. Both species died within 4 d of anoxic submergence. Anoxia intolerance would rule out hibernation in mud, which is anoxic. Both species survived long periods of normoxic submergence (R. pipiens, 125 d; R. catesbeiana, 150 d) with minimal changes in acid-base and ionic status. We conclude that ranid frogs require a hibernaculum where the water has a high enough Po(2) to drive cutaneous diffusion, allowing the frogs to extract enough O(2) to maintain aerobic metabolism, but that an ability to tolerate anoxia for several days may still be ecologically meaningful.     

Arterial supply of the choriocapillaris of anuran amphibians (Rana temporaria,Rana esculenta)

Summary The pattern of the vascular supply to the choroid of the frog eye was studied in toto with the use of the injection-replication-SEM technique. The choroid of anuran amphibians is composed mainly of the choriocapillaris. In both species studied (Rana temporaria, Rana esculenta), an independent arterial supply to the choriocapillaris supplemented that from the ciliary arteries. This additional vascular route arises from the optic artery, a separate branch of the arteria infundibularis superficialis. The optic artery, accompanied by its vein within the vascular sheath of the optic nerve, joins the rich arterial capillary network of the choriocapillaris and supplies the posterior pole of the ocular bulb. The superficial capillary network displays a dense collar around the entrance of the optic nerve into the eye and is composed of a circular meshwork of small capillaries, several layers deep. More peripherally, however, it becomes single layered. This capillary network, as a whole, establishes numerous connections with the adjacent choriocapillaris at the posterior pole of the ocular bulb. In anuran amphibians the complex arrangement of both arterial systems supporting the choriocapillaris may be regarded as a more complete equivalent of the short posterior ciliary arteries of mammals.     

Intracelomic use of tricaine methanesulfonate for anesthesia of bullfrogs (Rana catesbeiana) and leopard frogs (Rana pipiens)

The use of intracelomic injection of dissolved tricaine methanesulfonate (MS-222) as an anesthetic agent in two anuran species was studied. Intracelomic MS-222, at dosages of 100, 250, and 400 mg/kg, rapidly induced tranquilization or anesthesia. Effects were less pronounced or nonexistent at the 50 mg/kg dosage. Depth and duration of anesthesia were dosage related. At the 100, 250, and 400 mg/kg dosages, Rana pipiens attained a greater depth of anesthesia and remained anesthetized for a significantly greater duration than did R. catesbeiana. Dosages of between 250–400 mg/kg reliably induced deep anesthesia without mortality in bullfrogs. Dosages of less than 250 mg/kg are recommended for leopard frogs, since variable mortality was noted with higher dosages. Solubilized tricaine methanesulfonate did not cause gross or histopathological lesions to celomic tissues. Tricaine methanesulfonate injected intracelomically can provide rapid, efficient anesthesia in some anuran species. However, due to the observed intra- and interspecies variation in effect, it should be used cautiously, especially in unfamiliar species. © 1992 Wiley-Liss Inc.     

Glucocorticoid receptor of frog (Rana esculenta) liver

The presence of a glucocorticoid soluble receptor is demonstrated in frog liver cytosol. The kinetic characterization of frog liver cytosolic receptor for glucocorticoids is reported and its steroid specificity assessed. Results indicate a gross similarity between frog liver and mammalian glucocorticoid receptor, being a major difference the reduced binding capacity.     

阿尔泰林蛙的物种有效性及其分类地位——来自系统发育分析的证据

为检验阿尔泰林蛙(Rana altaica)的系统发育地位及其物种有效性,该文运用线粒体细胞色素b基因,应用贝叶斯分析和最大简约方法构建了欧哑人陆分布的部分林蛙的系统发育关系.两种分析方法均支持阿尔泰林蛙在田野林蛙(R.arvalis)这一分支的内部.单倍型网络图显示来自阿尔泰地区和中西伯利亚地区所谓的阿尔泰林蛙与田野林蛙有共享单倍型.通过该文母系遗传发育分析结果显爪阿尔泰林蛙种级地位不成立,是田野林蛙的同物异名.另外,该文实验分析结果提示,对中国分布的林蛙内部种组划分应建立在系统进化关系的基础上重新进行评估.     

Über die Sauerstoffbindung durch Hämoglobin vom Frosch (Rana esculenta und Rana temporaria)

Zusammenfassung Die Sauerstoffdissoziationskurven vom Blute von Rana esculenta und Rana temporaria wurden bei 20° bei verschiedenen Kohlensäurespannungen bestimmt.Für Rana esculenta wurde obendrein die O₂-Bindung bei 12° untersucht.Die für diese Versuche benutzten Apparate konnten mit Hilfe einer Spende der Rockefeller Foundation angeschafft werden.     

蛙属三种的核型研究

本文研究了蛙属三种：脆皮蛙、长趾蛙和威宁蛙的染色体核型,结果表明均具有蛙属典型的核型：2n=26,由5对大染色体和8对小染色体组成。三种在臂比值和次缢痕的有无、位置方面存在差异。同源染色体对间未发现异形现象。     

Range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) in northwestern North America

The dynamic geological and climatic history of northwestern North America has made it a focal region for phylogeography. We conducted a range-wide phylogeographic analysis of the spotted frog complex (Rana luteiventris and Rana pretiosa) across its range in northwestern North America to understand its evolutionary history and the distribution of clades to inform conservation of R. pretiosa and Great Basin R. luteiventris, candidates for listing under the US Endangered Species Act. Mitochondrial DNA sequence data from a segment of the cytochrome b gene were obtained from 308 R. luteiventris and R. pretiosa from 96 sites. Phylogenetic analysis revealed one main R. pretiosa clade and three main R. luteiventris clades, two of which overlapped in southeastern Oregon. The three R. luteiventris clades were separated from each other by high levels of sequence divergence (average of 4.75-4.97%). Two divergent clades were also uncovered within the Great Basin. Low genetic variation in R. pretiosa and the southeastern Oregon clade of R. luteiventris suggests concern about their vulnerability to extinction.     

Nutritional composition of frog (Rana esculanta) waste meal

In the present study, the waste obtained from the frozen frog leg industry was used for the production of frog waste meal, and its proximate, amino acids, fatty acids, mineral and vitamin compositions were evaluated to determine the nutritional quality. In addition, the total bacterial count, Salmonella, total volatile basic nitrogen (TVB-N, mgN/100g) and thiobarbituric acid (TBA, mg malonaldehyde/kg) were also measured to determine the microbiological and chemical quality of frog waste meal (FWM). The crude protein, fat and ash content of FWM on a dry weight basis were 68.6%, 17.0% and 13.2%, respectively. The amino acid profiles were found to be fairly close to those of fish meal in terms of protein sources and rich in the glutamic acid, glycine, proline, arginine, and methionine. The proportions of fatty acid composition in FWM were analysed and findings were 26.7% for total saturated fatty acid (SFA), 42.5% for total monounsaturated fatty acid (MUFA), 17.0% for total n - 6 and 3.3% for n - 3 ratio. The major SFA, MUFA and PUFA in FWM were palmitic acid (19.1%), oleic acid (26.0%) and linoleic acid (16.7%), respectively. FWM was found to be high in mineral content, especially Zn, K, Cu, Mn, and Mg and high level of some vitamins such as folic acids and thiamin. The total bacterial count was found to be 2.9x10(4) CFU/g, and Salmonella was not observed. TVB-N and TBA in FWM was determined to be 157.4+/-5.8 mg N/100g and 1.2+/-0.1 mg malonaldehyde/kg, respectively.     

Tyrosine aminotransferase activity of frog (Rana esculenta) liver

1. The presence of tyrosine aminotransferase is reported both in particulate and soluble fractions of frog liver. 2. The activity of the soluble enzyme of frog liver was investigated with regard to its dose and time dependence, its substrate specificity and concentration dependence, its thermal sensitivity as well as pH and temperature dependence. 3. It appears that the properties of the soluble tyrosine aminotransferase of frog liver are in close agreement with those reported for the mammalian liver enzyme.