Worldwide amphibians and reptiles are declining with habitat fragmentation and destruction as the primary cause. Riparian areas are important for the herpetofauna, but as land is converted to agriculture or harvested for timber the areas are diminishing. The aim of this study was to examine amphibian and reptile abundance in relation to distance from water and in relation to habitat characteristics, foremost per cent deciduous trees. The survey was conducted during spring at six different locations, with continuous forest along streams or rivers, outside of Karlstad, Sweden. Animals were searched along four lines parallel to the water and each study area was visited five times. Statistical analyses were made for grass snake (Natrix natrix), common lizard (Lacerta vivipara) and frogs with joined data of common frog (Rana temporaria) and moor frog (R. arvalis). As expected both reptiles were positively correlated with per cent deciduous trees, with the strongest significance for the common lizard. For grass snake there was also a difference between survey periods, which might reflect the importance of weather. Frogs revealed no trends to trees, but there was a significant difference for habitat characteristics like amount woody debris and per cent bare ground. None of the species were correlated with distance from water which was surprising, especially for the frogs which is more dependent on water than the reptiles. Grass snakes hunt in the water, but the common lizard has no such associations to the water, yet the latter did reveal a slight trend towards being more numerous closer to the water. The causes behind lacking correlation to distance from water may be many, but water characteristics seem very important. Many amphibians prefer warm and calm ponds over running water that in general are colder and likely to inhabit more predators. It was assumed that the amphibians breed in the streams or rivers, but it is possible that other water bodies may have served as breeding sites, which mean the starting point was incorrect.

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 95-104). Also available on the World Wide Web.

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Quantitative relationships between blood flow velocity, vessel diameter, width of the peripheral plasma layer and induction of thrombus formation were studied in small blood vessels of the retrolingual membrane and intestinal mesentery of the frog, Rana Pipiens, and of the cheek pouch of the golden hamster, Mesocricetus auratus. Blood flow velocity was measured by a modification of the technique described by Hugues (Arch. Int. de Physiol. 61: 565, 1953). Internal vessel diameters and widths of the total peripheral plasma layer were measured with an ocular micrometer. Thrombus thresholds were determined by graded electrical stimulation. Determinations were made on 202 vessels in retrolingual membranes of frogs prepared by single pithing. In 95 arterioles (diameters from 10 to 40 microns), the mean flow velocity was 2.84 mm/sec. and the mean volume flow rate, 1.68xl0-3 cu mm/sec. The mean width of the total peripheral plasma layer was 3.6 microns and its ratio to mean vessel diameter was 1:6. In 107 venules (diameters from 10 to 50 microns), the mean flow rate was 1.20 mm/sec. The mean volume flow rate was 1.02x10-3 cu mm/sec. The mean width of the total peripheral plasma layer was 4.1 microns and its ratio to mean vessel diameter was 1:7.4. The ratios of mean arterial to mean venous velocity and volume flow were 1:2.3 and 1:1.6 respectively. Measurements were made on 100 mesenteric vessels of frogs prepared by single pithing. In 50 arterioles (diameters from 15 to 45 microns), the mean velocity was 3.77 mm/sec. The mean volume flow was 3.05xlo-3 cu mm/sec. The mean width of the total peripheral plasma layer was 2. 7 microns and its ratio to mean vessel diameter was 1:11.5. In 50 venules (diameters from 20 to 50 microns), the mean velocity was 1.55 mm/sec. and the mean volume flow rate, 1.76x10-3 cu mm/sec. The mean width of the total peripheral plasma layer was 6.7 microns and its ratio to mean vessel diameter was 1:5.3. The ratios of mean arterial to mean venous velocity and volume flow were 1:2.3 and 1:1.7 respectively. A total of 109 mesenteric vessels were studied in frogs anesthetized with urethane. In 55 arterioles (diameters from 15 to 45 microns), the mean velocity was 3.28 mm/sec. The mean volume flow was 2.87x10-3 cu mm/sec. The mean width of the total peripheral plasma layer was 3.2 microns and its ratio to mean vessel diameter was 1:9.3. In 54 venules (diameters from 20 to 50 microns), the mean flow rate was 1.61 mm/sec. and the mean volume flow, 1.83x10-3 cu mm/sec. The mean width of the total peripheral plasma layer was 5.6 microns and its ratio to mean vessel diameter was 1:5.9. The ratios of mean arterial to mean venous velocity and volume flow were 1:2.0 and 1:1.5 respectively. In these three series of studies in the frog, no relationship was clearly apparent between velocity and either vessel diameter or width of the peripheral plasma layer in arterioles. Suggestions of a direct relationship between velocity and peripheral plasma layer in veins, however, were evident. In all cases, and in both arterioles and venules, vessel diameter and peripheral plasma layer were clearly and directly related. The effects of flow velocity changes on width of the total peripheral plasma layer in individual vessels were studied in 26 arterioles of the hamster cheek pouch. Blood flow was varied by means of a cuff described by Copley (Biorheology 1: 3, 1962). A direct relationship between velocity and width of the peripheral plasma layer was clearly demonstrated. Thrombus thresholds were determined in mesenteric vessels of the frog. In 103 arterioles (diameters from 20 to 140 microns), the mean strength of stimulus necessary to produce a platelet thrombus was 24.8 volts with an amperage of 0.18 milliamperes. In 100 venules (diameters from 20 to 140 microns), the mean strength of stimulus necessary was 20.7 volts with an amperage of 0.12 milliamperes. Possible relationships of thrombus thresholds to flow velocity in mesenteric arterioles and venules are discussed. / 2031-01-01

Per pusantrų metų 26 km ilgio kelyje Vilnius–Dūkštos užregistruota 378 žuvę gyvūnai, iš jų 44 žinduoliai (6 laukinių ir 3 naminių gyvūnų rūšys), 1 paukštis ir 333 varliagyviai (rudosios Rana genties varlės). Rastas 21 suvažinėtas baltakrūtis ežys, 8 katės, 4 šunys, 4 akmeninės kiaunės, 2 rudosios žiurkės, 2 geltonkaklės pelės, 1 lapę, 1 pilkasis kiškis ir 1 karvė. Varliagyviai masiškai žūva migruodami iš žiemojimo vietų į nerštavietes. Tiek 2005, tiek 2006 metais masinis rudųjų varlių žuvimas kelyje Vilnius–Dūkštos užregistruotas balandžio pirmąjį dešimtadienį. Daugiausia žinduolių ant kelio buvo suvažinėta šiltuoju metų laiku – rugpjūčio, gegužės ir rugsėjo mėnesiais. Kadangi gyvūnai ant kelių registruojami rytą, dauguma jų suvažinėjami tamsiu paros metu. Daugiausia žinduolių (27%) suvažinėta tose vietose, kur kelią supa krūmynai, 23% - gyvenvietėse ir miesteliuose, 20% – keliui einant pievomis ir 18% – pamiškėse. Kitų biotopų reikšmė gyvūnų žuvimui kelyje Vilnius–Dūkštos buvo nedidelė – miške užregistruota tik 9% žuvusių žinduolių. Ežiai ir varliagyviai suvažinėjami visame Vilnius–Dūkštos kelio ruože: varliagyviai – ties grioviais, upeliais, laukų pelkutėmis ir ten, kur kelią supa šlapi krūmynai, ežiai – kai kelias eina pievomis ir krūmuotomis vietomis. Ištirtoje kelio atkarpoje trūksta apie susidūrimą su gyvūnais perspėjančių kelio ženklų, pavojingose vietose nėra ribojamas greitis. Šios priemonės leistų sumažinti gyvūnų žuvimą. / Animal roadkills on the road were partly conditioned by overspeeding and insufficient number of the road signs. Our results show, that animal roadkills are quite big compared to the short road segment. In the foreign countries problems of the animal roadkills receive more attention, as except damage done to the nature, there are problems of safety, material losses and possible charges to a road service if warning road signs were absent. Object of this investigation were animals, killed on the road Vilnius–Dūkštos (segment length – 26 km). Aim this work was to evaluate species composition of the killed animals, seasonality and influence of the surrounding habitats. Investigation was done while driving this segment twice per day and registering animals killed. Rules of the road were obeyed – no stops under sign or interrupting other vehicles, thus, not all of the killed animals were collected or pictures taken. Places of the roadkills were mapped. In the period of 2004.11.01–2006.05.01number of killed animals was 378; out of these 44 mammals, 1 bird (young Tawny Owl) and 333 amphibians (common/moor frogs). Biggest number of mammal roadkills was done in the dark period of the day and in August–September, while that of amphibians – in April. No kills were registered in January and February. Species composition of mammals: 21 hedgehogs, 4 stone martens, 2 yellow-necked mice, 2 brown rats, 1 fox, 1 brown hare, 8 cats and 4 dogs. According our results and literature analysis... [to full text]

Per pusantrų metų 26 km ilgio kelyje Vilnius–Dūkštos užregistruota 378 žuvę gyvūnai, iš jų 44 žinduoliai (6 laukinių ir 3 naminių gyvūnų rūšys), 1 paukštis ir 333 varliagyviai (rudosios Rana genties varlės). Rastas 21 suvažinėtas baltakrūtis ežys, 8 katės, 4 šunys, 4 akmeninės kiaunės, 2 rudosios žiurkės, 2 geltonkaklės pelės, 1 lapę, 1 pilkasis kiškis ir 1 karvė. Varliagyviai masiškai žūva migruodami iš žiemojimo vietų į nerštavietes. Tiek 2005, tiek 2006 metais masinis rudųjų varlių žuvimas kelyje Vilnius–Dūkštos užregistruotas balandžio pirmąjį dešimtadienį. Daugiausia žinduolių ant kelio buvo suvažinėta šiltuoju metų laiku – rugpjūčio, gegužės ir rugsėjo mėnesiais. Kadangi gyvūnai ant kelių registruojami rytą, dauguma jų suvažinėjami tamsiu paros metu. Daugiausia žinduolių (27%) suvažinėta tose vietose, kur kelią supa krūmynai, 23% - gyvenvietėse ir miesteliuose, 20% – keliui einant pievomis ir 18% – pamiškėse. Kitų biotopų reikšmė gyvūnų žuvimui kelyje Vilnius–Dūkštos buvo nedidelė – miške užregistruota tik 9% žuvusių žinduolių. Ežiai ir varliagyviai suvažinėjami visame Vilnius–Dūkštos kelio ruože: varliagyviai – ties grioviais, upeliais, laukų pelkutėmis ir ten, kur kelią supa šlapi krūmynai, ežiai – kai kelias eina pievomis ir krūmuotomis vietomis. Ištirtoje kelio atkarpoje trūksta apie susidūrimą su gyvūnais perspėjančių kelio ženklų, pavojingose vietose nėra ribojamas greitis. Šios priemonės leistų sumažinti gyvūnų žuvimą. / Animal roadkills on the road were partly conditioned by overspeeding and insufficient number of the road signs. Our results show, that animal roadkills are quite big compared to the short road segment. In the foreign countries problems of the animal roadkills receive more attention, as except damage done to the nature, there are problems of safety, material losses and possible charges to a road service if warning road signs were absent. Object of this investigation were animals, killed on the road Vilnius–Dūkštos (segment length – 26 km). Aim this work was to evaluate species composition of the killed animals, seasonality and influence of the surrounding habitats. Investigation was done while driving this segment twice per day and registering animals killed. Rules of the road were obeyed – no stops under sign or interrupting other vehicles, thus, not all of the killed animals were collected or pictures taken. Places of the roadkills were mapped. In the period of 2004.11.01–2006.05.01number of killed animals was 378; out of these 44 mammals, 1 bird (young Tawny Owl) and 333 amphibians (common/moor frogs). Biggest number of mammal roadkills was done in the dark period of the day and in August–September, while that of amphibians – in April. No kills were registered in January and February. Species composition of mammals: 21 hedgehogs, 4 stone martens, 2 yellow-necked mice, 2 brown rats, 1 fox, 1 brown hare, 8 cats and 4 dogs. According our results and literature analysis... [to full text]

Current municipal wastewater treatment plants (MWWTP) technologies are insufficiently removing emerging contaminants of concern. These emerging contaminants are an issue as many are known endocrine disrupting compounds (EDCs). EDCs are contaminants that can have severe and irreversible impacts on highly conserved endocrine systems that are critical during developmental periods in vertebrates as well as during adult life. Many EDCs have non-monotonic dose-response curves yet they are not often tested at low, environmentally relevant concentrations. EDC research to date has focused heavily on xenoestrogenic compounds whereas thyroid hormone (TH) disruption has been largely overlooked. TH is conserved in all vertebrates and plays crucial roles in neural development, basal metabolism, and thermoregulation. TH is comprised of thyroxine (T4), often known as the transport form of TH, and triiodothyronine (T3), the more bioactive form of TH. A TH spike occurs in the perinatal period of humans, and when disrupted, this spike can cause severe developmental defects. An analogous, but perhaps more overt, TH spike occurs in amphibians. TH is the sole hormone that drives amphibian metamorphosis, thus providing an excellent model for TH action. Our lab has previously developed the cultured tailfin (C-fin) assay, which uses biopsies from premetamorphic Rana catesbeiana tadpole tailfins cultured in the presence of an exogenous chemical of concern to assess perturbations to TH- and stress-responsive gene transcript levels by QPCR. This thesis uses the C-fin assay to assess the efficacy of removal of biological TH- and stress-altering activity in conventional municipal wastewater treatment systems. We first assess the successive levels of a full-scale conventional activated sludge (CAS) MWWTP in its ability to reduce perturbations of mRNA transcript levels of the critical TH receptors alpha (thra) and beta (thrb), and stress responsive gene transcripts superoxide dismutase (sod), catalase (cat) and heat shock protein 30 (hsp30). Secondary treatment of wastewater effluents removes cellular stress perturbations when compared to influents, but thr disruptions remain after conventional secondary wastewater treatment. We then assess three pilot-sized conventional secondary MWWTP configurations run at two operational conditions. The C-fin assay results suggest that the current understanding of operational conditions and the efficiency of complex MWWTP configurations is not clear-cut when assessed by biological endpoints such as the transcript abundance perturbations in the C-fin assay. Finally, the C-fin assay is used to investigate transcript profiles of genes of interest when the tissues are treated with the endogenous hormones T3, T4, and estradiol (E2). Our results indicate that T4 acts as more than solely a T3-prohormone and that gene expression levels in response to the two different forms of TH can be T3 or T4 specific. E2 effects, although implicated in altering TH-mediated responses in other contexts, do not affect TH-responsive gene transcripts in the C-fin. The data presented use the novel C-fin assay to challenge and advance the currently accepted views of TH-action, as well as develop necessary yet practical biological knowledge for management of emerging contaminant release from MWWTPs. / Graduate / 0383 / 0768 / 0307 / polaw@uvic.ca

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2016-10-24T10:28:59Z No. of bitstreams: 1 texto completo.pdf: 1292318 bytes, checksum: adf0d8ebb06a97579d24ee6101cf8ddf (MD5) / Made available in DSpace on 2016-10-24T10:28:59Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1292318 bytes, checksum: adf0d8ebb06a97579d24ee6101cf8ddf (MD5) Previous issue date: 1996-02-28 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Foram estudados dois sistemas de evisceração de rãs (tradicional e alternativo), com o objetivo de verificar sua influência na qualidade das carcaças, estocadas sob refrigeração (4±1oC) até 15 dias, ou sob congelamento (-18±2oC), durante 180 dias. Periodicamente (0, 2, 4, 7, 10 e 15 dias, no caso da refrigeração, e 0, 30, 60, 90, 120, 150 e 180 dias, no caso do congelamento) foram realizadas análises microbiológicas (contagens de mesófilos, psicrotróficos, fungos e leveduras e NMP de coliformes totais e fecais), físico-químicas (pH, NNP, BVT e TBA) e sensorial (limosidade, textura, odor, brilho e cor). Os resultados das análises mostraram que o índice de BVT e as contagens de mesófilos e psicrotróficos foram os melhores indicadores das alterações, ocorridas no produto estocado sob refrigeração, o qual foi considerado apto para consumo até o oitavo dia. O odor, seguido da cor e da textura, foi o melhor atributo sensorial para se determinar a qualidade da carne refrigerada. Na carne de rã congelada, até 180 dias de estocagem, não foram detectadas alterações físico-químicas, microbiológicas ou sensoriais, que prejudicassem sua qualidade. Nenhum dos atributos sensoriais mostrou um comportamento, que permite ser utilizado como índice de qualiade de carne congelada. O sistema de evisceração alternativo mostrou-se superior ao tradicional, por apresentar menor contaminação com coliformes e por permitir menos operários na linha de abate. Sugere-se, portanto, a utilização do sistema de evisceração alternativo para o abate de rãs. / Two frog evisceration systems (traditional and alternative) were tested to verify their influence upon the quality of carcasses stored under refrigeration (4±1oC) or freezing (-18±2oC) for 15 or 180 days, respectively. Microbiological (mesophilic, psycrotrophic, molds and yeasts counts, MPN of total and fecal coliforms), physical-chemical (pH, TVB, NPN, TBA), and sensory (slime, texture, odour, brightness and color) evaluations were made periodically (0, 2, 4, 7, 10 and 15 days under refrigeration, and 0, 30, 60, 90, 120, 150 and 180 days, under freezing). The results showed that, TVB, mesophilic and psycrotrophic counts were the best indicators of the changes occuring on the product stored under refrigeration. Refrigerated frog meat was considered fit for consumption up to the eighth day of storage. Odour, followed by color and texture, was the best sensory attribute determining the quality of the refrigerated frog meat. On frozen frog meat, stored up to 180 days, no physical-chemical, microbiological or sensory alterations were detected that impair its quality. No sensory attribute showed a behavior that allow their utilization as a quality indicator of frozen frog meat. The alternative evisceration system showed to be superior than the traditional since it lead to less contamination with coliform and because it allows less workers in the slaughter line. It is sugested that the alternative evisceration system must be used for slaughtering frogs. / Não foram localizados o cpf do autor e o currículo lattes.

Orientador: José Paes de Almeida Nogueira Pinto / Banca: Vera Lucia Mores Rall / Banca: Luciano dos Santos Bersot / Resumo: O trabalho teve como objetivo avaliar a ocorrência de Salmonella spp. nos vários pontos do fluxograma do abate de rãs (Rana catesbeiana - Rã Touro), desde os currais de espera até o produto final, bem como nas vísceras não comestíveis e no fígado. Das 120 amostras analisadas ao longo do abate (15 amostras por ponto / 8 pontos de colheita), 39 (32,5%) mostraram-se positivas, independentemente do ponto de colheita. Em relação a estes, obtiveram-se os seguintes resultados: 26,7% de positividade na água dos currais de espera, 13,3% após a insensibilização e após a sangria, 26,7% após a retirada da pele, 46,7% após a evisceração, 40% no produto final não embalado e nas vísceras, e 53,3% para o fígado. Conclui-se que a carne de rã, produto final, obtida nas condições estudadas, pode representar um sério risco à saúde pública, como veículo de Salmonella spp. A contaminação detectada nos vários pontos de colheita se dá de forma gradativa e contínua ao decorrer do abate. Das etapas estudadas, a evisceração é a mais crítica em relação à contaminação por Salmonella spp. É necessária a implementação de pontos críticos de controle no processo de abate e, consequentemente, ações corretivas para minimizar tais contaminações. / Abstract: The study aimed to assess the occurrence of Salmonella spp. in several parts of the flowchart of the slaughter of frogs (Rana catesbeiana - Bullfrog), since the waiting pens until the final product, as well as in viscera not edible and in the liver. Of the 120 samples analyzed over the slaughter (15 samples per point / 8 points of collection), 39 (32,5%) have proved positive, regardless of the point of harvest. For these, obtained the following results: 26,7% of positivity in the water of waiting pens, 13,3% after stunning and after the bleeding, 26,7% after the withdrawal of skin, 46,7% after evisceration, 40% in the final product not packed and for the viscera, and 53,3% for the liver. It follows that the meat of frog, the final product, obtained under the conditions studied, may represent a serious risk to public health, as a vehicle of Salmonella spp. The contamination detected in the various points of collection occurs in a gradual and continuous course of the slaughter. In stages studied, the evisceration is the most critical point of the contamination by Salmonella spp. It's necessary establish critical points of control in the process of slaughter and, therefore, correct actions to minimize such contamination. / Mestre

The aim of this study was to determine the effect of density and kinship on the rate of metamorphosis of the selected species of frogs. The work was made in Rana temporaria, common frog. Tadpoles of this species have been bred at different densities kindred subjects. The regular weekly intervals were timed tadpoles until metamorphosis. It has been shown that tadpoles reared individually developed much faster and metamorphosed at larger sizes. Contrast, tadpoles raised in unrelated groups developed much more slowly than in the group composed of related individuals.

Pharmaceuticals polluting natural environments pose a greater and greater threat in today’s society. Benzodiazepines, the most common form of anxiolytic drug, can commonly be found in nature as a result of the release of human wastewater containing the drug, and have been shown to affect both fish and frog species in several different ways related to predator evasion. This study aims to determine whether a common benzodiazepine, oxazepam, has any inhibitory effect on induced behavioral defenses in the boreal frog species Rana temporaria. Larvae of R. temporaria were exposed to an oxazepam gradient, paired with three different predator regimes consisting of a control, an ambush-predator setting, and a pursuing-predator setting. The larvae were then filmed at three different Gosner stages during simulated predator encounters, while measuring maximum velocity and acceleration, as well as activity- and exploration level, and the duration of avoidance following each encounter. Tail related morphological traits were also measured in order to correlate velocity and acceleration with trait properties. Avoidance duration was found to decrease when exposed to ambush predators, regardless of oxazepam concentration. No other effect of predators could be found during this study, and no significant correlations between tail properties and velocity or acceleration were seen. Oxazepam was not found to inhibit any induced behavioral defenses, nor did it alter any of the examined behavioral traits.