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Disruption of recruitment in two endemic palms on Lord Howe Island by invasive rats
2010-01-01
Invasive species may have negative impacts on many narrow range endemics and species restricted to oceanic islands. Predicting recent impacts of invasive species on long-lived trees is difficult because the presence of adult plants may mask population changes. We examined the impact of introduced black rats (Rattus rattus) on two palm species restricted to cloud forests and endemic to Lord Howe Island, a small oceanic island in the southern Pacific. We combined estimates of the standing size distribution of these palms with the proximal impacts of rats on fruit survival in areas baited to control rats and in unbaited areas. The size distribution of palms with trunks was comparable across baited and unbaited sites. Small juvenile palms lacking a trunk (
1999-01-01
We tested the reliability of accelerator mass spectrometry (AMS) radiocarbon dates on bone gelatin by dating samples whose maximum or minimum age was constrained by stratigraphic position relative to well-dated volcanic tephra layers. The tephra layers were not reworked, and were thick enough to preclude the possibility of redeposition resulting in specimens being found outside the age bounds set by the tephras. The damp, fossiliferous, carbonate-rich sediment was in a relatively constant, cool environment in a small cave at nearly 900 m altitude. Bones from four species of bird with different diets (a pigeon, a rail, an owlet-nightjar, and a large ratite) and one rodent, the Pacific rate Rattus exulans, were dated. The calibrated (calendar) AMS age of each bone was compared to ages predicted from their stratigraphic position and calculated sedimentation rates, inferred ...
2010-01-01
The ship rat or black rat (Rattus rattus) is one of the most widespread invasive rodent species on earth, and is a known cause of extinction of several endemic species in invaded ecosystems. While some information is available for insular populations, very little is known about the genetic population structure of this species on mainland areas. In this study (the first to characterize genetic population structure of invasive R. rattus on the mainland), we focused on the population structure of rats located in Puketi Forest Conservation Reserve, Northland, New Zealand, to help conservation managers optimize control programs. We used eight microsatellite markers and classical population genetics tools (F st, clustering methods) as well as individual-based descriptive methods using GPS coordi...
2010-01-01
When the first Polynesian settlers arrived on Rapa Nui, about 70% of the island was covered with dense woodland in which Jubaea palms dominated. Our investigations of extended soil profiles provide evidence that more than 16 million palm trees grew on the island. Nearly all palms were removed by the 16th century. Teeth marks on nutshells of the Jubaea palms from the 13th or 14th centuries attest to the activity of Pacific rats (Rattus exulans) on Rapa Nui, which were probably imported there by the first Polynesians settlers. Did the rats perhaps prevent the germination of palm seeds and thus the regeneration of the dense palm woodland of Rapa Nui? The results of our investigations refute this hypothesis and support the assumption that people cut the trees. Burned relicts of palm stumps and...
Effects of invasive rats and burrowing seabirds on seeds and seedlings on New Zealand islands
2010-01-01
Rats (Rattus rattus, Rattus norvegicus, Rattus exulans) are important invaders on islands. They alter vegetation indirectly by preying on burrowing seabirds. These seabirds affect vegetation through nutrient inputs from sea to land and physical disturbance through trampling and burrowing. Rats also directly affect vegetation though consumption of seeds and seedlings. Seedling communities on northern New Zealand islands differ in composition and densities among islands which have never been invaded by rats, are currently invaded by rats, or from which rats have been eradicated. We conducted experimental investigations to determine the mechanisms driving these patterns. When the physical disturbance of seabirds was removed, in soils collected from islands and inside exclosures, seedling dens...
Examining sources of bias in radiocarbon ages of New Zealand Kiore
1997-12-31
Recent AMS dates for the Pacific rat (Rattus exulans / Kiore) from natural and archaeological sites are significantly older than the generally accepted time for human arrival in New Zealand. Because Rattus exulans is recognized as a human commensal for Polynesian colonization in Oceania, radiocarbon ages for Kiore could be used as an indicator of earliest human contact with New Zealand. A strictly chronological interpretation of the radiocarbon ages assembled, though, raises serious questions about this arrival time. Therefore, factors that could affect the age determinations were also examined. A research programme in progress at the Rafter Radiocarbon Laboratory aims to identify the range and influence of natural bias and variance in radiocarbon ages in kiore bone samples. It was found that the main factors that could bias these ages were the incomplete removal of contaminants by the current bone preparation methods, and dietary carbon reservoir effects. Preliminary results of the various analytical techniques employed are presented.
Study on the Movement of Rattus rattus and Evaluation of the Plague Dispersion in Madagascar
2010-01-01
Abstract Plague affects mainly the rural areas in the central highlands of Madagascar. Rattus rattus is the main rodent host of Yersinia pestis in these localities. Since the introduction of plague, endemic foci have continued to expand, and spatiotemporal variability in the distribution of human plague has been observed. To assess the movements of R. rattus and evaluate the risk of dispersion of the disease, a field study at the scale of the habitats (houses, hedges of sisals, and rice fields) in the plague villages was carried out during high and low seasons of plague transmission to humans. The systemic oral marker Rhodamine B was used to follow rats' movements. Baits were placed in different habitats, and trapping success was carried out once a month for 3 months after the bait distrib...
Dating the late prehistoric dispersal of Polynesians to New Zealand using the commensal Pacific rat
2008-01-01
The pristine island ecosystems of East Polynesia were among the last places on Earth settled by prehistoric people, and their colonization triggered a devastating transformation. Overhunting contributed to widespread faunal extinctions and the decline of marine megafauna, fires destroyed lowland forests, and the introduction of the omnivorous Pacific rat (Rattus exulans) led to a new wave of predation on the biota. East Polynesian islands preserve exceptionally detailed records of the initial prehistoric impacts on highly vulnerable ecosystems, but nearly all such studies are clouded by persistent controversies over the timing of initial human colonization, which has resulted in proposed settlement chronologies varying from ≈200 B.C. to 1000 A.D. or younger. Such differences underpin radically divergent interpretations of human dispersal from West Polynesia and of ecological and social transformation in East Polynesia and ultimately obfuscate the timing and patterns of this process. Using New Zealand as an example, we provide a reliable approach for accurately dating initial human colonization on Pacific islands by radiocarbon dating the arrival of the Pacific rat. Radiocarbon dates on distinctive rat-gnawed seeds and rat bones show that the Pacific rat was introduced to both main islands of New Zealand ≈1280 A.D., a millennium later than previously assumed. This matches with the earliest-dated archaeological sites, human-induced faunal extinctions, and deforestation, implying there was no long period of invisibility in either the archaeological or palaeoecological records.Janet M. Wilmshurst, Atholl J. Anderson, Thomas F. G. Higham and Trevor H. Worthy Publisher: Natl Acad Sciences Contributor: School of Earth and Environmental Sciences Other identifier: Proceedings of the National Academy of Sciences of the United States of America, 2008; 105(22):7676-7680; 0027-8424; 0020080857; 10.1073/pnas.0801507105; 000256648600011 Language: en
2010-01-01
Abstract Aim To describe the phylogeographic patterns of the black rat, Rattus rattus, from islands in the western Indian Ocean where the species has been introduced (Madagascar and the neighbouring islands of Reunion, Mayotte and Grande Comore), in comparison with the postulated source area (India). Location Western Indian Ocean: India, Arabian Peninsula, East Africa and the islands of Madagascar, Reunion, Grande Comore and Mayotte. Methods Mitochondrial DNA (cytochrome b, tRNA and D-loop, 1762 bp) was sequenced for 71 individuals from 11 countries in the western Indian Ocean. A partial D-loop (419 bp) was also sequenced for eight populations from Madagascar (97 individuals), which were analysed in addition to six previously published populations from southern Madagascar. Results Haplotyp...
2003-01-01
A population of South Georgian diving petrels (Pelecanoides georgicus) (c. 130 g) became extinct at Mason Bay, on the west coast of Stewart Island, before European settlement. Pacific rat (Rattus exulans) bones with the diving petrel fossils provided an opportunity to determine whether the rats arrived before the petrels went extinct. Fifteen 14C accelerator mass spectrometry (AMS) ages on purified diving petrel bone gelatin from various parts of Mason Bay clustered unexpectedly in the 14th and 15th centuries AD, and none was older. Bayesian statistical analysis, using a Markov Chain Monte Carlo procedure, gave a 95% probability that the diving petrel colony was founded between 1338 and 1440 AD, lasted 40-310 years, and became extinct between 1475 and 1650 AD. Possible reasons for the late colonisation of Mason Bay by South Georgian diving petrels burrow are ...
Qualitative and quantitative study of few enzymes in the liver of cadmium fed rats
1983-01-01
Cadmium when administered to animals is known to accumulate in the liver and kidney, causing identifiable toxic effects. These effects on enzyme systems have been described in the present investigation selecting few of them viz. alkaline phosphatase, acid phosphatase, glucose-6-phosphatase and cholinesterase in the liver of rat, Rattus rattus albino. Topographical studies dysenzymia thus made have been found helpful in understanding the mechanism of Cd toxicity. Variations in the level of enzyme protein, and the state of cellular organelles together with processes of phosphorylation, adenylation and oxidative phosphorylation have been discussed, explaining the cause and significance of these changes in enzyme activity.
Assessment of Rhodamine B for labelling the plague reservoir Rattus rattus in Madagascar
2010-01-01
Abstract The black rat is the main plague reservoir in rural foci in Madagascar, inside the villages as well as in the cultivated areas around. We have evaluated the potentialities of mass-marking of rats, using baits containing Rhodamine B (RB) in order to get a tool to study the movements of rats and to understand the spread of plague. Laboratory experiments demonstrated that: (i) rats were more attracted by the rodent granules and peanut butter; (ii) incorporation of RB in baits did not reduce their appetence; (iii) RB lasted for 60 days in rat vibrissae and 180 days in rat hairs; and (iv) consumption of baits during a week was under the lethal dose. Field tests have been realized comparatively among 24 highland villages where plague is endemic, in different contexts: baits inside house...
2006-01-01
The digenean trematode Echinoparyphium hydromyos was recorded from the dusky rat, Rattus colletti, and the water rat, Hydromys chrysogaster, from the Adelaide River floodplain, Northern Territory, Australia. The dusky rat represents a new host for E. hydromyos and the Adelaide River floodplain is a new locality. This echinostome has previously been reported only from the water rat in southern and eastern Australia. Publisher: US. : Helminthological Society of Washington, Relation: Comparative parasitology. US. : Helminthological Society of Washington,2006. vol. 73, no. 2 p. 289-290 1 page Refereed 1525-2647; aCQUIRe [electronic resource] : Central Queensland University Institutional Repository. Other identifier: cqu:404 Language: en-aus Source: Mulder, E & Smales, LR 2006, 'Dusky rat, Rattus colletti (Muridae), a new host for Echinoparyphium hydromyos (Trematoda: Digenea) in the Northern Territory, Australia', Comparative physiology, vol. 73, no. 2, pp. 289-290. Rights: By submitting a Work to aCQUIRe the author(s) grant(s) to Central Queensland University permission to publish the Work under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs Licence.
The case of an insular molarless black rat: Effects on lifestyle and mandible morphology
2010-01-01
We report a specimen of an insular black rat (Rattus rattus) from Illa den Colom (Menorca, Western Mediterranean) displaying a singular dental characteristic. It has no molar teeth but displays regular incisors. Its mere occurrence as a regular adult rat is puzzling and we attempted to evaluate what diet and morphological changes in jaw shape were promoted by the total lack of molars, and allowed the successful survival of this specimen. Two approaches were performed: first, bone tissue was analysed to obtain d^1^5N and d^1^3C values in order to estimate dietary preferences of the rat. Second, the shape of the jaw was analysed through elliptic Fourier analysis, using outlines as markers of diet. The values for C and N fractionation (-19.89%% and 10.06%%, respectively) suggest that the mola...
2009-07-01
We determined the sensitivity of perianal tape impressions to detect Syphacia spp. in rats and mice. We evaluated 300 rat and 200 mouse perianal impressions over 9 wk. Pinworm-positive...Full Text Available
Effects of 2.0-g 1.75-g and 1.5-g Hypergravity on Pregnancy Outcome in Rats (Rattus norvegicus)
In 1995, ten pregnant female rats were launched on the Space Shuttle (STS-70) on Gestational day(G) 11 of their 22-day pregnancy as part of the NASA/NIH.Rodent (R)2 Experiment. Following landing on G20, fetuses were ...
2010-01-01
Abstract The liver and kidney functional indices of weanling albino rats (Rattus norvegicus) maintained on different accessions (offspring of a variety planted/collected at a specific location and time but differing in certain morphological characteristics) of cooked Colocasia esculenta (cocoyam)-based diets (UFCe1UFCe7) for 28 days were investigated. All the accessions of C. esculenta-based diets did not significantly (P
Temperature affects microbial decomposition of cadavers (Rattus rattus) in contrasting soils
2008-01-01
The ecology of soils associated with dead mammals (i.e. cadavers) is poorly understood. Although temperature and soil type are well known to influence the decomposition of other organic resource patches, the effect of these variables on the degradation of cadavers in soil has received little experimental investigation. To address this, cadavers of juvenile rats (Rattus rattus) were buried in one of three contrasting soils (Sodosol, Rudosol, and Vertosol) from tropical savanna ecosystems in Queensland, Australia and incubated at 29 °C, 22 °C, or 15 °C in a laboratory setting. Cadavers and soils were destructively sampled at intervals of 7 days over an incubation period of 28 days. Measurements of decomposition included cadaver mass loss, carbon dioxide–carbon (CO2–C) evolution, microbial biomass carbon (MBC), protease activity, phosphodiesterase activity, and soil pH, which were all significantly positively affected by cadaver burial. A temperature effect was observed where peaks or differences in decomposition that at occurred at higher temperature would occur at later sample periods at lower temperature. Soil type also had an important effect on some measured parameters. These findings have important implications for a largely unexplored area of soil ecology and nutrient cycling, which are significant for forensic science, cemetery planning and livestock carcass disposal. Publisher: Elsevier Format: application/pdf Other identifier: Carter, David, Yellowlees, David, and Tibbett, Mark (2008) Temperature affects microbial decomposition of cadavers (Rattus rattus) in contrasting soils. Applied Soil Ecology, 40 (1). pp. 129-137. ISSN 1873-0272
Analysis of vkorc1 polymorphisms in Norway rats using the roof rat as outgroup
Full Text Available.BackgroundCertain mutations in the vitamin K epoxide reductase subcomponent 1 gene (vkorc1) mediate rodent resistance to warfarin and other anticoagulants. Testing for resistance often involves analysis of the vkorc1. However, a genetic test for the roof rat (Rattus rattus) has yet to be developed. Moreover, an available roof rat vkorc1 sequence would enable species identification based on vkorc1 sequence and the evaluation of natural selection on particular vkorc1 polymorphisms in the Norway rat (R. norvegicus).ResultsWe report the coding sequence, introns and 5' and 3' termini for the vkorc1 gene of roof rats (R. r. alexandrinus and R. r. frugivorus) from Uganda, Africa. Newly designed PCR primers now enable genetic testing of the roof rat and Norway rat. Only synonymous and noncoding polymorphisms were found in roof rats from Uganda. Both nominal subspecies of roof rats were indistinguishable from each other but were distinct from R. losea and R. flavipectus; however, the roof rat also shares at least three coding sequence polymorphisms with R. losea and R. flavipectus. Many of recently published vkorc1 synonymous and non-synonymous single nucleotide polymorphisms (SNPs) in Norway rats are likely SNPs from roof rats and/or other Rattus species. Tests applied to presumably genuine Norway rat vkorc1 SNPs are consistent with a role for selection in two populations carrying the derived Phe63Cys and Tyr139Cys mutations.ConclusionGeographic mapping of vkorc1 SNPs in roof rats should be facilitated by our report. Our assay should be applicable to most species of Rattus, which are intermediate in genetic distance from roof and Norway rats. Vkorc1-mediated resistance due to non-synonymous coding SNPs is not segregating in roof rats from Uganda. By using the roof rat sequence as a reference vkorc1, SNPs now can be assigned to the correct rat species with more confidence. Sampling designs and genotyping strategies employed so far have helped detect candidate mutations underlying vkorc1-mediated resistance, but generally provided unsuitable data to test for selection. We propose that our understanding of vkorc1-mediated evolution of resistance in rodents would benefit from the adoption of sampling and genotyping designs that enable tests for selection on vkorc1.
Hematological changes in the house rat after 32P internal irradiation
1982-01-01
Male house rats (Rattus rattus) were injected with 32P at the dose of 1.46 kBq/g body weight. The blood was collected at post-injection intervals of 1/4, 2, 4, 6 and 8 days and various hematological parameters were estimated. An initial decrease in leukocyte count and total plasma protein content (on days 2 to 4) was noted whereas erythrocyte count, hemoglobin percentage and hematocrit value decreased at later intervals only (on days 6 to 8). The plasma cholesterol level registered significant increase on day 2. The possible reasons for these changes have been discussed in the present report. (author)
Hematological changes in the house rat after /sup 32/P internal irradiation
1982-03-01
Male house rats (Rattus rattus) were injected with /sup 32/P at the dose of 1.46 kBq/g body weight. The blood was collected at post-injection intervals of 1/4, 2, 4, 6 and 8 days and various hematological parameters were estimated. An initial decrease in leukocyte count and total plasma protein content (on days 2 to 4) was noted whereas erythrocyte count, hemoglobin percentage and hematocrit value decreased at later intervals only (on days 6 to 8). The plasma cholesterol level registered significant increase on day 2. The possible reasons for these changes have been discussed in the present report.
1979-03-01
The present investigation reports on the topography of few enzymes viz-alkaline phosphatase, acid phosphatase, 5-nucleotidase and lipase in the kidney of rat, Rattus rattus albino after individual and combined treatments with molybdenum and copper. Molybdenum intake altered enzyme activities whereas total inhibition was caused by copper though lipase remained un-inhibited. Comparision of controls with the combined effects, revealed no appreciable difference in the topography of these enzymes. Reversible dysenzymia thus observed points towards the conditioned metal ion antagonism and repair in cellular membranes. Several hypothesises for their differential biochemical behavior, cause and significance in enzymological patterns have been considered. Reversible dysenzymia has been explained on the basis that copper becomes unavailable through interaction with molybdate to form either cupric molybdate or copper thiomolybdate which is ultimately excreted.
Moisture can be the dominant environmental parameter governing cadaver decomposition in soil
2010-01-01
Forensic taphonomy involves the use of decomposition to estimate postmortem interval (PMI) or locate clandestine graves. Yet, cadaver decomposition remains poorly understood, particularly following burial in soil. Presently, we do not know how most edaphic and environmental parameters, including soil moisture, influence the breakdown of cadavers following burial and alter the processes that are used to estimate PMI and locate clandestine graves. To address this, we buried juvenile rat (Rattus rattus) cadavers (~18g wet weight) in three contrasting soils from tropical savanna ecosystems located in Pallarenda (sand), Wambiana (medium clay), or Yabulu (loamy sand), Queensland, Australia. These soils were sieved (2mm), weighed (500g dry weight), calibrated to a matric potential of -0.01 megapa...
Invasive Non-Native Species' Provision of Refugia for Endangered Native Species
2010-01-01
Abstract: The influence of non-native species on native ecosystems is not predicted easily when interspecific interactions are complex. Species removal can result in unexpected and undesired changes to other ecosystem components. I examined whether invasive non-native species may both harm and provide refugia for endangered native species. The invasive non-native plant Casuarina stricta has damaged the native flora and caused decline of the snail fauna on the Ogasawara Islands, Japan. On Anijima in 2006 and 2009, I examined endemic land snails in the genus Ogasawarana. I compared the density of live specimens and frequency of predation scars (from black rats[Rattus rattus]) on empty shells in native vegetation and Casuarina forests. The density of land snails was greater in native vegetati...
We determined the sensitivity of perianal tape impressions to detect Syphacia spp. in rats and mice. We evaluated 300 rat and 200 mouse perianal impressions over 9 wk. Pinworm-positive perianal tape impressions from animals with worm burdens at necropsy were considered as true positives. Conversely, pinworm-negative perianal tape impressions from animals with worm burdens were considered false negatives. The sensitivity of perianal tape impressions for detecting Syphacia muris infections in rats was 100%, and for detecting Syphacia obvelata in mice was 85.5%. Intermittent shedding of Syphacia obvelata ova is the most probable explanation for the decreased sensitivity rate we observed in mice. We urge caution in use of perianal tape impressions alone for Syphacia spp. screening in sentinel mice and rats.
2006-02-15
Data gathered in this study suggested the exposure of rats and Algerian mice, living in an abandoned mining area, to a mixture of heavy metals. Although similar histopathological features were recorded in the liver and spleen of both species, the Algerian mouse has proved to be the strongest bioaccumulator species. Hair was considered to be a good biological material to monitor environmental contamination of Cr in rats. Significant positive associations were found between the levels of this element in hair/kidney (r = 0.826, n = 9, p < 0.01) and hair/liver (r = 0.697, n = 9, p = 0.037). Although no association was found between the levels of As recorded in the hair and in the organs, the levels of this element recorded in the hair, of both species, were significantly higher in animals captured in the mining area, which met the data from the organs analysed. Nevertheless, more studies will be needed to reduce uncertainty about cause-effect relationships. - The bioaccumulation of As and Cd and signs of renal histopathological injury proved the value of Algerian mice as a bioindicator species in the risk assessment of contaminated sites.
Plague in Central Java, Indonesia
Plague in man occurred from 1968 to 1970 in mountain villages of the Boyolali Regency in Central Java. Infected fleas, infected rats, and seropositive rats were collected in villages with human plague cases. Subsequent isolations of Yersinia pestis and seropositive rodents, detected during investigations of rodent plague undertaken by the Government of Indonesia and the WHO, attested to the persistence of plague in the region from 1972 to 1974. Since 1968, the incidence of both rodent and human plague has been greatest from December to May at elevations over 1000 m. Isolations of Y. pestis were obtained from the fleas Xenopsylla cheopis and Stivalius cognatus and the rats Rattus rattus diardii and R. exulans ephippium. The major risk to man has been fleas infected with Y. pestis of unique electrophoretic phenotype. Infected fleas were collected most often in houses. Introduced in 1920, rodent plague had persisted in the Boyolali Regency for at least 54 years. The recent data support specific requirements for continued plague surveillance. ImagesFig. 2
2007-01-01
The purpose of this study was to explore the effects of LPS-gram negative bacteria and low ambient temperature on free radicals (FR) production, the activities of lactate dehydrogenase (LDH) and glutathione peroxidase (GPx) in the lungs of rats, Rattus norvigisu. Twenty four male rats, matched with age and weigh, were divided randomly into four groups namely control (C), Bacteria (B), cold temperature (T), and bacteria plus cold (BT). The T group was exposed to 10-12degree C ambient temperature for 3 days. Animals of the BT was injected LPS bacteria (IP, 500 micron g/kg) during the last five hour of cold exposure to 10-12 degree C for 3 days. In comparison with C group FR increased significantly (pactivity of LDH increased significantly (p
2006-01-01
levanox, a hepato protective drug, and garlic powder have been considered as safe anti-oxidant agents. the present investigation included physiological, radiometric and molecular studies to evaluate the protective role of levanox and/or garlic tablets toward CCl4 - induced toxicity in adult male albion rats ( Rattus norvegicus).CCl4 intoxication, at oral dose of 0.03 ml/kg of rat body weight, led to severe tissue damage as revealed by an elevation of serum activities of AST, ALT, ALP, CK and LDH. CCl4 caused an elevation of serum triglycerides with no effect on serum total cholesterol. it also increased serum creatinine and urea levels . these biochemical results were in coincidence with the liver and kidneys histopathological alterations . using radioimmunoassay, it was found that serum total testosterone level was significantly ...
2010-01-01
The myotendon junction (MTJ) is a specialised area into the muscle fibers where the sarcoplasmic membranes connect to the collagen fibers bundles. There are few data about plasticity of the MTJ in aging processes. The aim of this study is to analyse the ultrastructure characteristics of MTJ of medial pterygoid muscle of adult and aged rats. Employing the transmission electron microscopy method, twenty male rats Wistar (Rattus norvegicus) were divided into two groups: A (n=10) with 12 months of age; B (n=10) 24 months of age. The animals were anaesthetised with overdose the urethane (3g/kg, i.p.) and sacrified during the perfusion with modified Karnovsky solution. The specimens were post-fixed in a 1% osmium tetroxide solution, dehydrated in ascending concentration of ethanol and embedded i...
2007-01-01
Poi WR, Carvalho RM, Panzarini SR, Sonoda CK, Manfrin TM, Rodrigues TS. Influence of enamel matrix derivative (Emdogain) and sodium fluoride on the healing process in delayed tooth replantation: histologic and histometric analysis in rats. Copyright Blackwell Munksgaard, 2006. Abstract - Although it has already been shown that enamel matrix derivative (Emdogain) promotes periodontal regeneration in the treatment of intrabony periodontal defects, there is little information concerning its regenerative capacity in cases of delayed tooth replantation. To evaluate the alterations in the periodontal healing of replanted teeth after use of Emdogain, the central incisors of 24 Wistar rats (Rattus norvegicus albinus) were extracted and left on the bench for 6 h. Thereafter, the dental papilla and ...
2005-01-01
Abstract: Determining the inter-island migration abilities of pest species and delimiting eradication units enable more viable long-term eradication campaigns because recurrent colonization from neighboring islands is avoided. We examined the genetic structure of the invasive Norway rat (Rattus norvegicus) to identify gene flow between islands and delimit population units at different geographical scales. We investigated variation in eight microsatellite loci in rat populations from 18 islands, representing five archipelagos off the Brittany coast (France). Although most of the islands are isolated from each other, short genetic distances, weak FSTvalues between close islands, and a high level of cross-assignment showed that individuals collected on different islands could represent a sing...
Effect of sodium selenite on bone repair in tibiae of irradiated rats
2009-01-01
This study evaluated the radioprotective effect of sodium selenite on the bone repair process in tibiae of female rats. For such purpose, 100 female Wistar rats (Rattus norvegicus, albinus) were randomly assigned to 4 groups (n=25), according to the treatment received: administration of distilled water (control). Administration of sodium selenite. Gamma radiation. And administration of sodium selenite plus gamma radiation. A bone defect was prepared on both tibiae of all animals. Three days after surgery, the gamma radiation and selenium/ gamma radiation groups received 8 Gy gamma rays on the lower limbs. Five animals per group were sacrificed 7, 14, 21, 28 days after surgery for evaluation of the repair process by bone volumetric density analysis. The 5 animals remaining in each group were sacrificed 45 days postoperatively for examination of the mature bone by scanning ...
Do rats (Rattus norvegicus) perceive biological motion?
2010-01-01
It is unknown whether the rodent visual system can perceive biological motion, an ability present in primates, cats, and several bird species. Using a water-maze visual discrimination task, we find that rats can be trained to distinguish between left- and rightward motion of abstract point-light displays of walking humans. However, rats were unable to generalize to a novel point-light display (a walking cat), or to a display of a backward walking human, where overall body configuration and local, ballistic foot motion provide directly opposing cues regarding movement direction. Together, these experiments provide the first demonstration of the ability of rodents to extract motion direction cues from abstract, point-light displays. However, when isolated, neither the overall body configurat...
Quality of diets with fluidized bed combustion residue treatment: I. Rat trials
Feeding trials were conducted with rats (Rattus rattus) to examine effects of soil application, or dietary inclusion, of fluidized bed combustion residue (FBCR) on the composition and quality of foods. Four diets (vegetable protein, egg protein, chicken, chicken + dietary FBCR) prepared with either FBCR or lime (control) treatments, were fed to weanling, female rats in three growth and reproduction trials. Intake, growth rate, and composition of body and organs of rats were measured. Rats in one trial were bred, their litters maintained on dietary treatments, and the offspring rebred. Treatment (FBCR vs. lime) x diet interactions on food composition and animal responses generally were not significant. Treatment had little effect on element composition of diets; mineral concentrations were in normal ranges. Diet treatment with FBCR depressed (P<0.01) food intake and growth of rats in one trial, but not in others, and had no effect (P<0.05) on body water, protein, ether extract, or gross energy composition. Some differences in element concentrations in the carcass and organs of rats and pups resulted from FBCR treatment, but effects were small and inconsistent. Litters from the first reproductive cycle appeared normal, except for animals fed the chicken + dietary FBCR treatment, on which pups showed poor growth and anemia. Offspring from certain diets were rebred and litters showed a high mortality, although this was not associated specifically with FBCR treatment. Results indicated no major detrimental effects on food composition, or growth, tissue element accumulation, and reproduction in the rat relating to use of FBCR as a soil amendment. 20 refs., 9 tabs.
Metabolism of insecticide chemicals in the egyptian animals rattus rattus and spodoptera littoralis
1981-01-01
The degradation rate of 14 C-cyolane in rate and spodoptera littoralis larvae has been investigated. 1) Rat experiments: a) following a single oral dose of radioactive cyolane (2 m/Kg), the total radioactivity for (48.5%) of the administered dose, the major part has been eliminated after 24 hours (37%), during the next 5 days a remarkable decrease in the elimination rate was observed. b) for separation and identification of the metabolic products thin layer chromatography and paper chromatography have used. At least 5 14C-labelled metabolites could be separated in addition to the parent compound (3%). 2)-Spodoptera littoralis larvae experiments:- a) For the topically applied dose 14 C-cyolane, (5 Mu g/g larvae), the excreta contained 30 - 40% after 20 hours. 14 CO2 in the expired air accounted for 3-4% and the ...
2010-01-01
ABSTRACT The aim of this study was to investigate the influence of acid adaptation in the survival of Salmonella Enteritidis (SE86) and Salmonella Typhimurium (ST99) during exposure to simulated gastric fluid (SGF) and in intestinal infection of Rattus norvegicus. Acid-adapted and nonadapted Salmonella strains were exposed to SGF (pH 1.5) and were inoculated by gavage in adult rats. Results indicated that acid-adapted SE86 survived significantly better (P 0.05) than nonadapted SE86, nonadapted ST99 and acid-adapted ST99 in SGF. Nonadapted microorganisms were observed in higher counts in feces than acid-adapted strains, while acid-adapted microorganisms demonstrated higher counts in intestine samples, suggesting intestinal invasion capacity. Acid-adapted SE86 was recovered in higher counts ...
2009-01-01
This study was planned to investigate the protective effect of L(+)-ascorbic acid (Vit C) on CCl4-induced hepatotoxicity and oxidative stress in the liver of Wistar rats (Rattus Norvegicus, strain Wistar). Twenty-four adult male Wistar rats were fed with standard rat chow diet for 10 days and randomly were divided into four groups of six each as follows: (1) control, (2) CCl4, (3) "CCl4 + Vit C", (4) Vit C groups. CCl4 was applied to rats belonging to CCl4 and "CCl4 + Vit C" groups subcutaneously at 1 mg kg-1 dose CCl4 for 3 days. Vit C applied to "CCl4 + Vit C" and "Vit C" group rats intraperitoneally at 300 mg kg-1 dose for 3 days. All rats were sacrificed and livers were quickly removed on the fourth day of the experiment. MDA, total glutathione (T.GSH) levels and superoxide dismutase (...
2010-01-01
Vitamin A is an essential micronutrient that regulates many biological processes through modulation of retinoic acid receptor-responsive genes. Vitamin A acts as a systemic antioxidant, participating in the modulation of diverse redox mechanisms involved in physiological and pathological processes. Different studies, however, observed that vitamin A and other retinoids may induce pro-oxidant/deleterious actions under certain conditions, leading to impairment of brain and lung function. Here, we studied the effect of vitamin A treatment at oral doses of 100IU/kg, 200IU/kg, and 300IU/kg to female rats (Rattus norvegicus) during pregnancy and lactation on oxidative parameters of lungs from the offspring vitamin A supplementation induced increases in lipoperoxidation, protein carbonyl, activit...
2009-01-01
Many animal species use their forelimbs to assist in eating, such as occurs in a reach-to-eat task (skilled reaching) in which a forelimb is extended to grasp food that is placed in the mouth for eating. It is unclear the extent to which the skilled reaching movements of different species share common ancestry and so are homologous or evolved independently and so are analogous (homoplasy). Here hand shaping (the movements of the hand and digits) that occur as the hand is transported to the target, were examined using high-speed (1000frames/s) video recording and kinematic measurement (Peak Motus) in the rat (Rattus norvegicus) and human (Homo sapiens). Ten movement similarities were identified from the point that the limb initiated transport towards the food item to the point that the food...
Family matters: Maternal and litter-size effects on immune parameters in young laboratory rats
2010-01-01
A functional immune system is important for the survival of mammalian young, particularly at weaning when they lose the immunological support provided by the mother's colostrum and milk. In altricial mammals, litter size and maternal characteristics are important components of an animal's early environment, which affect postnatal growth and development. In a study of unculled litters of Long-Evans laboratory rats (Rattus norvegicus), we asked whether such parameters are also associated with the immune status of the young shortly before weaning. On postnatal day 17, we assessed numbers of several leukocyte and lymphocyte subsets, the activity of the complement system, and immunoglobulin G (IgG) concentrations in the serum. Averaging the values of all pups per litter, we found negative corre...
2010-01-01
At least six families of mammalian acid lipases (E.C. 3.1.1.-) catalyse the hydrolysis of triglycerides in the body, designated as LIPA (lysosomal), LIPF (gastric), LIPJ (testis) and LIPK, LIPM and LIPN (epidermal), which belong to the AB hydrolase superfamily. In this study, in silico methods were used to predict the amino acid sequences, secondary and tertiary structures, and gene locations for acid lipase genes and encoded proteins using data from several mammalian genome projects. Mammalian acid lipase genes were located within a gene cluster for each of the 8 mammalian genomes examined, including human (Homo sapiens), chimpanzee (Pons troglodytes), rhesus monkey (Macacca mulatta), mouse (Mus musculus), rat (Rattus norvegicus), cow (Bos taurus), horse (Equus caballus) and dog (Canis fa...
STUDIES ON INDUCED HEPATOTOXICITY IN MALE ALBINO RATS (RATTUS NORVEGICUS)
2008-01-01
Levanox, a hepato protective drug, and garlic powder have been considered as safe anti-oxidant agents. The present investigation refers to biochemical and molecular studies to evaluate the protective role of levanox and/or garlic powder toward CCl4-induced toxicity in adult male albino rats. CCl4 intoxication was attempted using a dose of 0.03 ml/kg of rat body weight.Pre-treatment with levanox (one capsule/ kg of rat body weight, each capsule contains 100 mg catechu, 7.5 mg dandelion, 75 mg termiric 2% curcumin, 17.5 mg silymarin, 100 mg lecithin) was more effective than garlic powder (100mg/kg of rat body weight) in reducing CCl4-induced hepatotoxicity as revealed by its higher potency in reducing elevation of aspartate (AST) and alanine (ALT) aminotransferases in serum. Serum of control rats and those treated with levanox or garlic or CCl4 ...
2010-01-01
A study was performed to evaluate the effect of contaminated water on the tissues of Rattus novergicus (albino rats). Test rats were given water contaminated with lead (0.015 µg L-1 tap water), phenol (0.05 mL L-1 tap water), and benzene (0.05 mL L-1 tap water), while control rats were given tap water over a period of 65 days after which the activity of selected enzymes of the heart and serum was assayed, and hematological parameters and serum lipid profiles were also determined. Generally, a significant (p < 0.05) drop in the activity of the enzymes was observed in the heart of test rats relative to the control rats. However, the serum activities increased significantly in the test group compared to the control group (p < 0.05). The concentrations of serum cholesterol, low-...
Repellent effect of some household products on fly attraction to cadavers
2009-01-01
The most common task of a forensic entomologist is to determine an accurate minimum post-mortem interval (PMI) using necrophagous fly larvae found on carrion. More often, blowflies (Diptera: Calliphoridae) are the first insects to detect the cadaver and, if the circumstances are favourable, to leave eggs on the body. However, several studies reveal that products such as gas or paint found on the cadaver induce a delay in the colonisation of the body, leading to an under-estimate of the PMI. Six common household products (gas, mosquito citronella repellent, perfume, bleach, hydrochloric acid and soda) were added to dead rats (Rattus norvegicus) in a field (Lille Forensic Institute, France). The presence of necrophagous flies was checked at regular intervals during 1 month. This experiment w...
Mechanisms of imidacloprid resistance in Nilaparvata lugens by molecular modeling
2010-01-01
Homology models of the ligand binding domain of the wild-type and Y151S mutant brown planthopper (Nilaparvata lugens) a1 and rat (Rattus norvegicus) b2 nicotinic acetylcholine receptor (nAChR) subunits were generated based on the crystal structure of acetylcholine binding protein of Lymnaea stagnalis. Neonicotinoid insecticide imidacloprid was docked into the putative binding site of wild-type and mutant a1b2 dimeric receptors by Surflex-docking, and the calculated docking energies were in agreement with experimental results. The resistance mechanisms and corresponding binding modes of imidacloprid on nAChRs containing the Y151S target-site mutation were discussed.
2010-01-01
The diet selection of Desert Eagle Owl (Bubo ascalaphus) was investigated in the outskirts of Hurghada, the Egyptian Western Desert, and the results were used to test the main hypotheses describing the urbanization process of these birds. The diet primarily comprised mammals (78%) and birds (11.3%), with a small proportion of arthropods (9.2%) and reptiles (2.1%). The diet had a low diversity and was dominated by the two mammal species and a temporally abundant migrant bird species. The mammalian component of the diet is the most important in terms of biomass (91.7%), with the Norway Rat (Rattus norvegicus) dominating both by number (66.1%) and by biomass (89.1%). The results suggest that in the urban environments of Hurghada the Desert Eagle Owl is an opportunistic feeder, relying on exot...
1984-01-01
The distribution, elimination and metabolism of fenvalerate, alpha-cyano-3-phenoxy-benzyl-2-(4-chlorophenyl) isovalerate, was studied in Japanese quail. Adult birds were administered 100 mg/kg chlorophenyl labeled [14C]-fenvalerate and the excreta collection at designated time intervals. At the termination of the study, 72 hours post-dosing, tissues were removed for residue analysis. It was found that 90% of the administered dose was eliminated in the excreta within the first 24 hours. Chloroform extracts of the excreta samples were subjected to thin layer chromatography (TLC) and radioautography. Radioassay following combustion analysis of tissues showed the presence of extremely low residue levels in brain, heart, lung, kidney and liver. Fat and skin appear to accumulate residues but still the levels were very low. Time-course ...
2005-01-01
Venoms of spiders and wasps are well recognized to present high affinity to the central nervous tissue of many mammalian species. Here we describe the effects of direct exposure of rat (Rattus norvegicus) brains to the crude and denatured venom of the Brazilian social wasp Polybia ignobilis. Lower doses of crude venom injected via intracerebroventricular (i.c.v.) inhibited the exploratory activity of animals, while higher doses provoked severe generalized tonicclonic seizures, with hind limb extension. The status epilepticus lasted for few minutes leading the animals to respiratory depression and death. In contrast, the denatured venom was anticonvulsant against acute seizures induced by the i.c.v. injection of bicuculline, picrotoxin and kainic acid, but it was ineffective against seiz...
1989-10-15
Full Text Available.Systemic infection with Escherichia coli significantly decreased feed intake, slowed growth of the whole body and skeletal muscles, and severely inhibited muscle protein accumulation in both chicks and rats. Treatment with naproxen (6-methoxy-alpha-methyl-2-naphthaleneacetic acid), an inhibitor of prostaglandin production, decreased weight losses of body and muscle, and significantly inhibited muscle protein wasting in infected chicks and rats. E. coli infection increased net protein degradation by 44.8% (P less than 0.05) and prostaglandin E2 production by 148% (P less than 0.05) in isolated extensor digitorum communis muscle from chicks on day 2 after infection. Naproxen treatment significantly decreased net protein degradation and prostaglandin E2 production in infected chicks to values seen in muscles of healthy controls. Quantitatively and qualitatively similar results were seen in isolated rat epitrochlearis muscle.
Genome sequence of the brown Norway rat yields insights into mammalian evolution
The laboratory rat (Rattus norvegicus) is an indispensable tool in experimental medicine and drug development, having made inestimable contributions to human health. We report here the genome sequence of the Brown Norway (BN) rat strain. The sequence represents a high-quality 'draft' covering over 90 percent of the genome. The BN rat sequence is the third complete mammalian genome to be deciphered, and three-way comparisons with the human and mouse genomes resolve details of mammalian evolution. This first comprehensive analysis includes genes and proteins and their relation to human disease, repeated sequences, comparative genome-wide studies of mammalian orthologous chromosomal regions and rearrangement breakpoints, reconstruction of ancestral karyotypes and the events leading to existing species, rates of variation, and lineage-specific and lineage-independent evolutionary events such as expansion of gene families, orthology relations and protein evolution.
Genome sequence of the brown Norway rat yields insights into mammalian evolution
2004-02-02
The laboratory rat (Rattus norvegicus) is an indispensable tool in experimental medicine and drug development, having made inestimable contributions to human health. We report here the genome sequence of the Brown Norway (BN) rat strain. The sequence represents a high-quality 'draft' covering over 90 percent of the genome. The BN rat sequence is the third complete mammalian genome to be deciphered, and three-way comparisons with the human and mouse genomes resolve details of mammalian evolution. This first comprehensive analysis includes genes and proteins and their relation to human disease, repeated sequences, comparative genome-wide studies of mammalian orthologous chromosomal regions and rearrangement breakpoints, reconstruction of ancestral karyotypes and the events leading to existing species, rates of variation, and lineage-specific and lineage-independent evolutionary events such as expansion of gene families, orthology relations and protein evolution.
Effect of sodium selenite on bone repair in tibiae of irradiated rats
2009-07-01
This study evaluated the radioprotective effect of sodium selenite on the bone repair process in tibiae of female rats. For such purpose, 100 female Wistar rats (Rattus norvegicus, albinus) were randomly assigned to 4 groups (n=25), according to the treatment received: administration of distilled water (control); administration of sodium selenite; gamma radiation; and administration of sodium selenite plus gamma radiation. A bone defect was prepared on both tibiae of all animals. Three days after surgery, the gamma radiation and selenium/ gamma radiation groups received 8 Gy gamma rays on the lower limbs. Five animals per group were sacrificed 7, 14, 21, 28 days after surgery for evaluation of the repair process by bone volumetric density analysis. The 5 animals remaining in each group were sacrificed 45 days postoperatively for examination of the mature bone by scanning electron microscopy. Based on all analyzed parameters, the results of the present study suggest that sodium selenite exerted a radioprotective effect in the bone repair of tibia of irradiated rats. (author)
2005-01-01
Mammalian genome contains a wide variety of repetitive DNA sequences of relatively unknown function. We report a novel 227 bp simple repeat DNA (3.3 DNA) with a d left brace(GA) 7A (AG) 7right brace dinucleotide mirror repeat from the rat (Rattus norvegicus) genome. 3.3 DNA showed 75-85% homology with several eukaryotic mRNAs due to (GA/CU) n dinucleotide repeats by nBlast search and a dispersed distribution in the rat genome by Southern blot hybridization with [32P]3.3 DNA. The d left brace(GA) 7A (AG) 7right brace mirror repeat formed a triplex (H-DNA)-like structure in vitro. Two large RNAs of 9.1 and 7.5 kb were detected by [32P]3.3 DNA in rat brain by Northern blot hybridization indicating expression of such simple sequence repeats at ...
Hemoglobin affinity in Andean rodents.
Blood hemoglobin oxygen affinity (P50) was measured in three Andean species and in the laboratory rat (control), all raised near sea level. Chinchilla lanigera (Molina, 1792) has an altitudinal habitat range from low Andean slopes up to 3000 m., while Chinchilla brevicaudata (Waterhouse, 1848) has an altitudinal range from 3000 to 5000 m. The laboratory type guinea pig, wild type guinea pig (Cavia porcellus), (Waterhouse, 1748), and laboratory rat (Rattus norvegicus) were also raised at sea level. The Andean species had high hemoglobin oxygen affinities (low P50) compared with the rat. Chinchilla brevicaudata had a higher affinity than Chinchilla lanigera. The wild type guinea pig had a higher affinity than the laboratory type. As has been shown in other species, this is another example of an inverse correlation between the altitude level and the P50 values. This is the first hemoglobin oxygen affinity study in Chinchilla brevicaudata.
2009-01-01
Parathion in technical or formulated form at a sub-lethal dose of 1/20 LD50 was applied orally or dermally at 2-day interval for three months to determine its effect on RNA, DNA and protein content as well as RNA ase and DNA ase activity in different organs liver, brain and kidneys of adult male albino rats. Also, serum GOT, GPT and ALP activity as well as serum total soluble protein, albumin, globulin, bilirubin and uric acid content were determined in adult male albino rats (Rattus norvegicus). In addition, the present studies were undertaken to investigate different biological activities of the above parameters of black nightshades (Solanum nigrum L) methanolic extract. Two kinds of experimental works were taken off (antioxidants and protective). The results showed that technical and formulated parathion increased RNA and protein content but the content of DNA ...
Toxic substances enter the food chain by various routes. Extrapolation of potential adverse effects from basic toxicity studies is difficult, but practical considerations also limit the utility food chain studies. Hexachlorobenzene (HCB) appears to be more readily absorbed by cats (Felis catus) from contaminated pork than as a pure compound, but it is difficult to generate a frankly toxic product by feeding pigs (Sus scrofa domesticus) HCB. Polychlorimated biphenyls (PCB's) should not accumulate readily in soil-plant-animal chains, but PCB congeners exhibit a wide range of bioavailability and toxicity, cautioning against excessive extrapolation. Cadmium levels in food chains are greatly influenced by agronomical practices. Cadmium bound to metallothionein (MTN) is less bioavailable in short-term feeding studies, although it is reportedly more acutely toxic than CdCl/sub 2/ to some species. Long-term feeding of liver and kidney from high-Cd sewage-sludge-exposed sows, however, had no adverse effect on male or female rats (Rattus norvegicus). Male rats first accumulated organic Cd at a greater rate, but CdCl/sub 2/ ultimately produced higher kidney residues after 6 to 8 weeks. The CdCl/sub 2/ was more toxic to rate duodenal muscosa than was Cd-MTN purified from swine liver. These studies tend to support the concept of food-chain attenuation as well as enhancement of trace substance toxicity.
Toxic substances enter the food chain by various routes. Extrapolation of potential adverse effects from basic toxicity studies is difficult, but practical considerations also limit the utility food chain studies. Hexachlorobenzene (HCB) appears to be more readily absorbed by cats (Felis catus) from contaminated pork than as a pure compound, but it is difficult to generate a frankly toxic product by feeding pigs (Sus scrofa domesticus) HCB. Polychlorimated biphenyls (PCB's) should not accumulate readily in soil-plant-animal chains, but PCB congeners exhibit a wide range of bioavailability and toxicity, cautioning against excessive extrapolation. Cadmium levels in food chains are greatly influenced by agronomical practices. Cadmium bound to metallothionein (MTN) is less bioavailable in short-term feeding studies, although it is reportedly more acutely toxic than CdCl/sub 2/ to some species. Long-term feeding of liver and kidney from high-Cd sewage-sludge-exposed sows, however, had no adverse effect on male or female rats (Rattus norvegicus). Male rats first accumulated organic Cd at a greater rate, but CdCl/sub 2/ ultimately produced higher kidney residues after 6 to 8 weeks. The CdCl/sub 2/ was more toxic to rate duodenal muscosa than was Cd-MTN purified from swine liver. These studies tend to support the concept of food-chain attenuation as well as enhancement of trace substance toxicity.
Effects of Cisplatin on the Sperm Morphology of Rattus Orvegicus
2001-01-01
The mutagenicity and genotoxicity of chemotherapeutic drugs used as chemical antibiotics in most tumors as anticarcinogenic agents were studied. Cis-diammine-dichloroplatinum (cisplatin) is a commonly used chemotherapeutic agent in the treatment of ovarian testicular and bladder cancer. It is used intravenously, intraarterially and intraperitoneally. Group I adult male rats were injected with single dose at a level of 1/2 LD 50 (16mg/kg body weight (a half carcinogenic dose). Group II rats were treated with 9 mg/kg body weight (recommended dose) intraperitoneally injected. The abnormally shaped sperms were recorded after 1, 2, 3, 4 and 5 weeks post-injection. The frequency of abnormally shaped sperms was noted within the first three week post-injection, and highly significant abnormalities were recorded at the end of second week (181.4+-24.9) and (145.1+-28.6) in ...
The distribution, elimination and metabolism of fenvalerate, ..cap alpha..-cyano-3-phenoxy-benzyl-2-(4-chlorophenyl) isovalerate, was studied in Japanese quail. Adult birds were administered 100 mg/kg chlorophenyl labeled (/sup 14/C)-fenvalerate and the excreta collection at designated time intervals. At the termination of the study, 72 hours post-dosing, tissues were removed for residue analysis. It was found that 90% of the administered dose was eliminated in the excreta within the first 24 hours. Chloroform extracts of the excreta samples were subjected to thin layer chromatography (TLC) and radioautography. Radioassay following combustion analysis of tissues showed the presence of extremely low residue levels in brain, heart, lung, kidney and liver. Fat and skin appear to accumulate residues but still the levels were very low. Time-course studies of fenvalerate reveal that the radiocarbon peaks at 3 hours (9 ..mu..g/g) in the liver and gradually declines while in the blood it peaks within 2 hours and falls quickly to an equilibrium value of 1.5 ..mu..g/ml blood. The rapid excretion, lesser absorption and faster metabolism of fenvalerate probably explain the lower toxicity of this pesticide to birds compared to rats.
1984-01-01
The distribution, elimination and metabolism of fenvalerate, ..cap alpha..-cyano-3-phenoxy-benzyl-2-(4-chlorophenyl) isovalerate, was studied in Japanese quail. Adult birds were administered 100 mg/kg chlorophenyl labeled (/sup 14/C)-fenvalerate and the excreta collection at designated time intervals. At the termination of the study, 72 hours post-dosing, tissues were removed for residue analysis. It was found that 90% of the administered dose was eliminated in the excreta within the first 24 hours. Chloroform extracts of the excreta samples were subjected to thin layer chromatography (TLC) and radioautography. Radioassay following combustion analysis of tissues showed the presence of extremely low residue levels in brain, heart, lung, kidney and liver. Fat and skin appear to accumulate residues but still the levels were very low. Time-course studies of fenvalerate reveal that the radiocarbon peaks at 3 hours (9 ..mu..g/g) in the liver and gradually declines while in the blood it peaks within 2 hours and falls quickly to an equilibrium value of 1.5 ..mu..g/ml blood. The rapid excretion, lesser absorption and faster metabolism of fenvalerate probably explain the lower toxicity of this pesticide to birds compared to rats.
Anti-inflammatory and anti-pyretic activities of earthworm extract-Lampito mauritii (Kinberg)
2009-01-01
Aim of the study Experiments were conducted to understand the therapeutic properties such as anti-inflammatory and anti-pyretic activities of biologically active extract isolated from whole earthworm (Lampito mauritii, Kinberg). Materials and methods Inflammation in the hind paw of Wistar albino rat, Rattus norvegicus, was induced by histamine, granuloma pouch was induced by turpentine and pyrexia induced by Brewers yeast in rats were followed as earlier studies. Anti-inflammatory drug-indomethacin and anti-pyretic drug-paracetamol were used as standard drug for comparison. Results Administration of indomethacin (10mg/kg), paracetamol (150mg/kg) and/or different doses of earthworm extract (EE) (50, 100 and 200mg/kg) reduced and restored to normal conditions in a dose-dependent manner of hi...
Low Levels of Physical Activity Increase Metabolic Responsiveness to Cold in a Rat (Rattus fuscipes)
Full Text Available.BackgroundPhysical activity modulates expression of metabolic genes and may therefore be a prerequisite for metabolic responses to environmental stimuli. However, the extent to which exercise interacts with environmental conditions to modulate metabolism is unresolved. Hence, we tested the hypothesis that even low levels of physical activity are beneficial by improving metabolic responsiveness to temperatures below the thermal neutral zone, thereby increasing the capacity for substrate oxidation and energy expenditure.Methodology/Principal FindingsWe used wild rats (Rattus fuscipes) to avoid potential effects of breeding on physiological phenotypes. Exercise acclimation (for 30 min/day on 5 days/week for 30 days at 60% of maximal performance) at 22°C increased mRNA concentrations of PGC1α, PPARδ, and NRF-1 in skeletal muscle and brown adipose tissue compared to sedentary animals. Lowering ambient temperature to 12°C caused further increases in relative expression of NRF-1 in skeletal muscle, and of PPARδ of brown adipose tissue. Surprisingly, relative expression of UCP1 increased only when both exercise and cold stimuli were present. Importantly, in sedentary animals cold acclimation (12°C) alone did not change any of the above variables. Similarly, cold alone did not increase maximum capacity for substrate oxidation in mitochondria (cytochrome c oxidase and citrate synthase activities) of either muscle or brown adipose tissue. Animals that exercised regularly had higher exercise induced metabolic rates in colder environments than sedentary rats, and temperature induced metabolic scope was greater in exercised rats.Conclusions/SignificancePhysical activity is a necessary prerequisite for the expression of transcriptional regulators that influence a broad range of physiological functions from energy metabolism to cardiovascular function and nutrient uptake. A sedentary lifestyle leads to decreased daily energy expenditure because of a lack of direct use of energy and a muted metabolic response to ambient temperature, which can be reversed even by low levels of physical activity.
1997-01-01
Whole Document restricted for copyright reasons.The Ouvea Parakeet Eunymphicus cornutus uvaeensis, is an endangered bird endemic to Ouvea, Loyalty Islands, in the New Caledonian archipelago. Its population is estimated to be 300-600 birds, mainly in patches of forest in the north, with few parakeets in the centre and the south of the island. Its main habitat is high forest mixed with Melanesian fields. Within habitat distribution is very patchy, with an apparent site attachment during the breeding season. Radio tracking revealed that the home range of juveniles was small, and no dispersal was observed. The diet of the parakeets comprises the seeds and fruits of more than 23 plant species, including Ficus spp., Carica papaya and Rhamnella vitiensis. These plants have a long and asynchronous fruiting season, leading to an apparent abundance of food during the year. The number of breeding pairs was correlated with the density of potential nest sites in the three study areas, suggesting a nest site limitation. The length of the breeding season (August until January) allows the occurrence of double clutches. The parakeets nest in secondary cavities of only five species of trees (90% n Syzygium pseudopinnatum and Mimusops elengii). The clutch size is 2.9 eggs (range 2-4), of which on average 2.6 chicks hatch, 1.65 fledge, but only 0.75 per breeding pair is still alive 30 days after fledging. The main causes of loss are starvation of the third sibling due to hatching asynchrony, human harvest, and raptor predation after fledging. Ouvea is free of Ship Rat Rattus rattus and Norway Rat R. norvegicus. Kiore R. exulans, the rat present, is responsible for only a few predations at nests. The main predators are the Brown Goshawk Accipiter fasciatus, and humans that capture chicks to sell them as pets. 15-30 chicks are still captured every year and sold outside Ouvea. A population viability analysis of the Ouvea Parakeet shows that, with the current carrying capacity, this harvest is not sustainable and would eventually lead to extinction. Long-term survival would be best secured by establishing another population of 4-500 birds in the south of Ouvea, by increasing carrying capacity through habitat protection, nest site provision and restoration, decreasing the harvest and preventing the introduction of Ship Rat in Ouvea. Publisher: ResearchSpace@Auckland Language: en Rights: Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated.; http://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm; Copyright: The author
Transmission, reservoir hosts and control of zoonotic visceral leishmaniasis.
Zoonotic visceral leishmaniasis (ZVL) caused by Leishmania infantum is an important disease of humans and dogs. Here we review aspects of the transmission and control of ZVL. Whilst there is clear evidence that ZVL is maintained by sandfly transmission, transmission may also occur by non-sandfly routes, such as congenital and sexual transmission. Dogs are the only confirmed primary reservoir of infection. Meta-analysis of dog studies confirms that infectiousness is higher in symptomatic infection; infectiousness is also higher in European than South American studies. A high prevalence of infection has been reported from an increasing number of domestic and wild mammals; updated host ranges are provided. The crab-eating fox Cerdocyon thous, opossums Didelphis spp., domestic cat Felis cattus, black rat Rattus rattus and humans can infect sandflies, but confirmation of these hosts as primary or secondary reservoirs requires further xenodiagnosis studies at the population level. Thus the putative sylvatic reservoir(s) of ZVL remains unknown. Review of intervention studies examining the effectiveness of current control methods highlights the lack of randomized controlled trials of both dog culling and residual insecticide spraying. Topical insecticides (deltamethrin-impregnated collars and pour-ons) have been shown to provide a high level of individual protection to treated dogs, but further community-level studies are needed.
Surveys in 2001, 2005, and 2006 attempted to determine the role of wildlife in maintenance and dissemination of the tropical bont tick, Amblyomma variegatum (F.) (Acari: Ixodidae), in St. Croix, U.S. Virgin Islands. Small mammals; birds; white-tailed deer, Odocoileus virginianus (Zimmermann); and feral cattle, Bos taurus L., were examined at nine premises, in mountainous rain forest, and in surrounding areas in western St. Croix, an area including and central to all known bont tick-infested premises on the island. Small Asian mongooses, Herpestes javanicus (E. Geoffroy Saint-Hilaire), yielded 1,566 ectoparasite specimens, representing five species, and including larvae of a soft tick, Carios puertoricensis (Fox); the tropical horse tick, Anocentor nitens (Neumann); and the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini). Black rats, Rattus rattus L., yielded 144 specimens, representing six ectoparasite species, including C. puertoricensis. Of 25 bird species examined, seven yielded 116 ectoparasite specimens representing at least 14 different species of lice and mites, but no ticks. White-tailed deer and feral cattle yielded only various stages of A. nitens and R. microplus ticks. A. variegatum was not encountered on any potential wildlife host sampled, reflecting its low occurrence in St. Croix during the survey period. One collection of chewing lice (Phthiraptera: Philopteridae) from a spotted sandpiper, Actitis macularia (L.), and collections of feather mites (Acari: Astigmata: Trouessartiidae) from both bananaquits, Coereba flaveola (L.), and black-faced grassquits, Tiaris bicolor (L.), may represent new, undescribed species.
A survey of the vectors of spotted fever group Rickettsiae and of murine typhus was carried out in Rahat, a Bedouin town in the Negev Desert, where the diseases are endemic. Houses with known cases of spotted fever group Rickettsiae or murine typhus were compared with those without reported clinical cases. A neighboring Jewish community, Lehavim, where no cases of spotted fever group Rickettsiae and murine typhus were reported in recent years, was used as a control. In the houses of patients with spotted fever group Rickettsiae in Rahat, an average of 7.4 times more ticks were found than in control houses. Out of 190 ticks isolated from sheep and goats or caught by flagging in Rahat, 90% were Rhipicephalus sanguineus (Latreille), 7.9% Rhipicephalus turanicus Pomerantzev, and 2.1% were Hyalomma sp. In the houses of patients with murine typhus, three times more rats were caught and, on the average, each rat was infested with 2.2 times more fleas than rats in the control houses. Out of 323 fleas collected from 35 Norwegian rats (Rattus norvegicus Berkenhout), 191 were Xenopsylla cheopis Rothschild and 132 Echidnophaga murina Tiraboschi. Thus, there was a six to seven times higher probability of encountering a tick or flea vector where infections had occurred than in control houses in Rahat. The percentage of rats seropositive to Rickettsia typhi was similar in study and control households (78.3 and 76.2, respectively). In the control settlement, Lehavim, only three Mus musculus L. were caught, which were not infested with ectoparasites and their sera were negative for murine typhus. Out of 10 dogs examined in this settlement, 15 R. sanguineus and eight specimens of the cat flea (Ctenocephalides felis felis Bouch) were isolated. No rats were caught in this settlement. These data indicate that there is a correlation among the density of domestic animals, their ectoparasites, and the incidence of spotted fever group Rickettsiae and murine typhus in Rahat.
1986-01-01
Adult Japanese quail were administered 100 mg/kg chlorophenyl-labeled [14C]fenvalerate, alpha-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate, for study of its distribution, elimination, and metabolism. Ninety percent of the administered dose was eliminated in the excreta within the first 24 h. In addition to fenvalerate, the following metabolites were present: benzeneacetic acid, 4-chloro-alpha-(1-methylethyl)-,cyano(3-phenoxy-4-hydroxyphenyl)methyl ester [4'-OH-fenvalerate]. Benzeneacetic acid, 4-chloro-alpha-(1-methylethyl)-,(aminocarbonyl)(3-phenoxyphenyl)methyl ester [CONH2-fenvalerate]. 4-chloro-alpha-(1-methylethyl)benzeneacetic acid[Cl-V acid]. 4-chloro-alpha-(2-hydroxy-1-methylethyl)benzeneacetic ...
2010-01-01
The protective effect of Eucalyptus tereticornis leaf extract and its potency has been compared with Liv.52 following V2O5, induced hepatotoxicity in albino rats. LD50 estimated for V2O5, was 69.6 mg/kg b.wt. The administered doses of V2O5, were LD50/10th for acute and 1/7th, 1/14th and 1/21th of sublethal dose for subacute (7, 14 and 21 ds) respectively. Body weight, liver weight and hepatosomatic index were assessed. Hepatotoxicity was assessed in terms of hepatic total proteins, total lipids and total cholesterol. V2O5 intoxication significantly increased liver weight, hepatosomatic index, total lipids and total cholesterol, while significantly decreased body weight and total ...
Food habits of rodents in grain godowns of Karachi, Pakistan
2008-01-01
The present study is based on identification of stomach contents of three commensal rodents (Rattus rattus, Rattus norvegicus, Mus sp.) and the common house shrew (Suncus murinus), which were collected from the Thole Produce Yard rice godowns, Karachi. The relative frequency of individual plant and animal food items were calculated as percentages.The stomachs of 88% of 65 R. rattus and 85% of 39 R. norvegicus contained insect remains as did the stomachs of 93% of 84 Mus sp. All stomachs of S. murinus contained remains of economically important stored-grain insect pests. It is concluded that insects can be a significant component of the diet of these commensal rodents.
Epidemiology of Bartonella Infection in Rodents and Shrews in Taiwan
2010-01-01
Summary During the period of August 2002 and November 2004, an epidemiological investigation for Bartonella infection was conducted in small mammals in Taiwan. Using whole blood culture on chocolate agar plates, Bartonella species were successfully isolated from 41.3% of the 310 animals tested. The isolation rate of Bartonella species varied among different animal species, including 52.7% of the 169 Rattus norvegicus, 28.6% of the 126 Sucus murinus, 10% of the 10 Rattus rattus and 66.7% of the three Rattus losea. Bacteremia prevalence also varied with the origin of the animals, as 56.2% of the animals captured on farms, 38.6% of the ones captured at harbour sites and 11.8% of the animals captured from urban areas were bacteremic. Through molecular analysis of the gltA gene and 16S/23S inte...
Many animal species use their forelimbs to assist in eating, such as occurs in a reach-to-eat task (skilled reaching) in which a forelimb is extended to grasp food that is placed in the mouth for eating. It is unclear the extent to which the skilled reaching movements of different species share common ancestry and so are homologous or evolved independently and so are analogous (homoplasy). Here hand shaping (the movements of the hand and digits) that occur as the hand is transported to the target, were examined using high-speed (1000 frames/s) video recording and kinematic measurement (Peak Motus) in the rat (Rattus norvegicus) and human (Homo sapiens). Ten movement similarities were identified from the point that the limb initiated transport towards the food item to the point that the food was grasped. The digits were closed and semi-flexed as the hand was lifted (released from a substrate) and supinated. They closed further as the hand was collected for aiming. They then extended as the hand was transported to the target and then opened in conjunction with pronation to orient the hand for grasping (manipulation). Finally the digits were flexed and closed for grasping. These movements occurred at approximately the same point of limb transport in both species even though the rat used a whole paw grasp and the humans used a pincer grasp. Bushbabies (Galago garnettii), titi monkeys (Callicebus brunneus), rhesus monkeys (Macaca mulatta) and the bonobo (Pan paniscus) displayed similar hand shaping in skilled reaching despite species differences in grasping movements. Homologous hand shaping in the rodent clade and the primate clade and within the primate lineage is discussed in relation to its possible derivation from hand shaping movements associated with stepping.
Full Text Available.BackgroundThe aim of this study was to investigate, in vivo, the quality of bone healing under the effect of a static magnetic field, arranged inside the body.MethodsA metallic device was developed, consisting of two stainless steel washers attached to the bone structure with titanium screws. Twenty-one Wistar rats (Rattus novergicus albinus) were used in this randomized experimental study. Each experimental group had five rats, and two animals were included as control for each of the groups. A pair of metal device was attached to the left femur of each animal, lightly touching a surgically created bone cavity. In the experimental groups, washers were placed in that way that they allowed mutual attraction forces. In the control group, surgery was performed but washers, screws or instruments were not magnetized. The animals were sacrificed 15, 45 and 60 days later, and the samples were submitted to histological analysis.ResultsOn days 15 and 45 after the surgical procedure, bone healing was more effective in the experimental group as compared to control animals. Sixty days after the surgical procedure, marked bone neoformation was observed in the test group, suggesting the existence of continued magnetic stimulation during the experiment.ConclusionThe magnetic stainless steel device, buried in the bone, in vivo, resulted in increased efficiency of the experimental bone healing process.
BackgroundThe aim of this study was to investigate, in vivo, the quality of bone healing under the effect of a static magnetic field, arranged inside the body.MethodsA metallic device was developed, consisting of two stainless steel washers attached to the bone structure with titanium screws. Twenty-one Wistar rats (Rattus novergicus albinus) were used in this randomized experimental study. Each experimental group had five rats, and two animals were included as control for each of the groups. A pair of metal device was attached to the left femur of each animal, lightly touching a surgically created bone cavity. In the experimental groups, washers were placed in that way that they allowed mutual attraction forces. In the control group, surgery was performed but washers, screws or instruments were not magnetized. The animals were sacrificed 15, 45 and 60 days later, and the samples were submitted to histological analysis.ResultsOn days 15 and 45 after the surgical procedure, bone healing was more effective in the experimental group as compared to control animals. Sixty days after the surgical procedure, marked bone neoformation was observed in the test group, suggesting the existence of continued magnetic stimulation during the experiment.ConclusionThe magnetic stainless steel device, buried in the bone, in vivo, resulted in increased efficiency of the experimental bone healing process.
Adult Japanese quail were administered 100 mg/kg chlorophenyl-labeled (/sup 14/C)fenvalerate, ..cap alpha..-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate, for study of its distribution, elimination, and metabolism. Ninety percent of the administered dose was eliminated in the excreta within the first 24 h. In addition to fenvalerate, the following metabolites were present: benzeneacetic acid, 4-chloro-..cap alpha..-(1-methylethyl)-,cyano(3-phenoxy-4-hydroxyphenyl)methyl ester (4'-OH-fenvalerate); benzeneacetic acid, 4-chloro-..cap alpha..-(1-methylethyl)-,(aminocarbonyl)(3-phenoxyphenyl)methyl ester (CONH/sub 2/-fenvalerate); 4-chloro-..cap alpha..-(1-methylethyl)benzeneacetic acid(Cl-V acid); 4-chloro-..cap alpha..-(2-hydroxy-1-methylethyl)benzeneacetic acid(4-OH-Cl-V acid). In time course studies radiocarbon peaked at 3 h (9..mu..g/g) in the liver and gradually declined, while in the blood it peaked within 2 h and fell quickly to an equilibrium value of 1.5 ..mu..g/mL blood. In liver microsomal and isolated heptatocyte preparations of Japanese quail and rat, the following metabolites were identified: Cl-V acid, 4-OH-Cl-V acid, 4'-OH-fenvalerate, CONH/sub 2/-fenvalerate. Oxidation was found to be the predominant route of degradation either pre- or post-hydrolysis of the parent compound. Rapid excretion, lesser absorption, and faster metabolism probably explain the lower toxicity of fenvalerate to birds compared to rats.
Adult Japanese quail were administered 100 mg/kg chlorophenyl-labeled (/sup 14/C)fenvalerate, ..cap alpha..-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate, for study of its distribution, elimination, and metabolism. Ninety percent of the administered dose was eliminated in the excreta within the first 24 h. In addition to fenvalerate, the following metabolites were present: benzeneacetic acid, 4-chloro-..cap alpha..-(1-methylethyl)-,cyano(3-phenoxy-4-hydroxyphenyl)methyl ester (4'-OH-fenvalerate); benzeneacetic acid, 4-chloro-..cap alpha..-(1-methylethyl)-,(aminocarbonyl)(3-phenoxyphenyl)methyl ester (CONH/sub 2/-fenvalerate); 4-chloro-..cap alpha..-(1-methylethyl)benzeneacetic acid(Cl-V acid); 4-chloro-..cap alpha..-(2-hydroxy-1-methylethyl)benzeneacetic acid(4-OH-Cl-V acid). In time course studies radiocarbon peaked at 3 h (9..mu..g/g) in the liver and gradually declined, while in the blood it peaked within 2 h and fell quickly to an equilibrium value of 1.5 ..mu..g/mL blood. In liver microsomal and isolated heptatocyte preparations of Japanese quail and rat, the following metabolites were identified: Cl-V acid, 4-OH-Cl-V acid, 4'-OH-fenvalerate, CONH/sub 2/-fenvalerate. Oxidation was found to be the predominant route of degradation either pre- or post-hydrolysis of the parent compound. Rapid excretion, lesser absorption, and faster metabolism probably explain the lower toxicity of fenvalerate to birds compared to rats.
2009-01-01
Although rats have clearly contributed to bird extinctions on islands, their role in plant extinctions is not as clear. Paleoenvironmental studies suggest rats were responsible for the demise of several island palm species. French Polynesias islands provide an opportunity to evaluate modern? impacts of rats on native flora. Our study shows that 15 threatened taxa (nine families) are damaged by rats. All 12 subjected to seed predation are woody plants with large-seeded drupes. Three experience severe predation and recruitment depression (Santalum insulare, Ochrosia tahitensis, Nesoluma nadeaudii). Three-year monitoring of Polynesian sandalwood (Santalum insulare) populations in Tahiti during rat control suggested that over 99% of fruits were eaten before ripening. Seed predation on ...
Ion Channel Gene Expression in the Inner Ear
2007-09-01
Full Text Available.The ion channel genome is still being defined despite numerous publications on the subject. The ion channel transcriptome is even more difficult to assess. Using high-throughput computational tools, we surveyed all available inner ear cDNA libraries to identify genes coding for ion channels. We mapped over 100,000 expressed sequence tags (ESTs) derived from human cochlea, mouse organ of Corti, mouse and zebrafish inner ear, and rat vestibular end organs to Homo sapiens, Mus musculus, Danio rerio, and Rattus norvegicus genomes. A survey of EST data alone reveals that at least a third of the ion channel genome is expressed in the inner ear, with highest expression occurring in hair cell-enriched mouse organ of Corti and rat vestibule. Our data and comparisons with other experimental techniques that measure gene expression show that every method has its limitations and does not per se provide a complete coverage of the inner ear ion channelome. In addition, the data show that most genes produce alternative transcripts with the same spectrum across multiple organisms, no ion channel gene variants are unique to the inner ear, and many splice variants have yet to be annotated. Our high-throughput approach offers a qualitative computational and experimental analysis of ion channel genes in inner ear cDNA collections. A lack of data and incomplete gene annotations prevent both rigorous statistical analyses and comparisons of entire ion channelomes derived from different tissues and organisms.Electronic supplementary materialThe online version of this article (doi:10.1007/s10162-007-0082-y) contains supplementary material, which is available to authorized users.
Ion Channel Gene Expression in the Inner Ear
The ion channel genome is still being defined despite numerous publications on the subject. The ion channel transcriptome is even more difficult to assess. Using high-throughput computational tools, we surveyed all available inner ear cDNA libraries to identify genes coding for ion channels. We mapped over 100,000 expressed sequence tags (ESTs) derived from human cochlea, mouse organ of Corti, mouse and zebrafish inner ear, and rat vestibular end organs to Homo sapiens, Mus musculus, Danio rerio, and Rattus norvegicus genomes. A survey of EST data alone reveals that at least a third of the ion channel genome is expressed in the inner ear, with highest expression occurring in hair cell-enriched mouse organ of Corti and rat vestibule. Our data and comparisons with other experimental techniques that measure gene expression show that every method has its limitations and does not per se provide a complete coverage of the inner ear ion channelome. In addition, the data show that most genes produce alternative transcripts with the same spectrum across multiple organisms, no ion channel gene variants are unique to the inner ear, and many splice variants have yet to be annotated. Our high-throughput approach offers a qualitative computational and experimental analysis of ion channel genes in inner ear cDNA collections. A lack of data and incomplete gene annotations prevent both rigorous statistical analyses and comparisons of entire ion channelomes derived from different tissues and organisms.Electronic supplementary materialThe online version of this article (doi:10.1007/s10162-007-0082-y) contains supplementary material, which is available to authorized users.
Earlier studies demonstrated that forestomach herbivores are less insulin sensitive than monogastric omnivores. The present study was carried out to determine if different distribution patterns of the glucose transporters GLUT1 and GLUT4 may contribute to these different insulin sensitivities. Western blotting was used to measure GLUT1 and GLUT4 protein contents in oxidative (masseter, diaphragm) and glycolytic (longissimus lumborum, semitendinosus) skeletal muscle membranes of monogastric omnivores (rats and pigs), and of forestomach herbivores (cows, adult goats, goat kids, and camels). Muscles were characterized biochemically. Comparing red and white muscles, the isocitrate dehydrogenase (ICDH) activity was 1.5-15-times higher in oxidative muscles of all species, whereas lactate dehydrogenase (LDH) activity was 1.4-4.4-times higher in glycolytic muscles except in adult goats. GLUT4 levels were 1.5-6.3-times higher in oxidative muscles. GLUT1 levels were 2.2-8.3-times higher in glycolytic muscles in forestomach herbivores but not in monogastric animals. We conclude that GLUT1 may be the predominant glucose transporter in glycolytic muscles of ruminating animals. The GLUT1 distribution patterns were identical in adult and pre-ruminant goats, indicating that GLUT1 expression among these muscles is determined genetically. The high blood glucose levels of camels cited in literature may be due to an "NIDDM-like" impaired GLUT4 activity in skeletal muscle.
Venoms of spiders and wasps are well recognized to present high affinity to the central nervous tissue of many mammalian species. Here we describe the effects of direct exposure of rat (Rattus norvegicus) brains to the crude and denatured venom of the Brazilian social wasp Polybia ignobilis. Lower doses of crude venom injected via intracerebroventricular (i.c.v.) inhibited the exploratory activity of animals, while higher doses provoked severe generalized tonic-clonic seizures, with hind limb extension. The status epilepticus lasted for few minutes leading the animals to respiratory depression and death. In contrast, the denatured venom was anticonvulsant against acute seizures induced by the i.c.v. injection of bicuculline, picrotoxin and kainic acid, but it was ineffective against seizures caused by systemic pentylenetetrazole. Moreover, the [3H]-glutamate binding in membranes from rat brain cortex was inhibited by the denatured venom in lower concentrations than the [3H]-GABA binding. The denatured venom contains free GABA and glutamate (34 and 802 pg/microg of venom, respectively), but they are not the major binding inhibitors. These interactions of venom components with GABA and glutamate receptors could be responsible for the anticonvulsant effects introducing the venom from P. ignobilis as a potential pharmacological source of anticonvulsant drugs.
Remote Forest Refugia for Fijian Wildlife
2006-01-01
Abstract: On Pacific islands non-native rats and mongooses threaten many native species. In Fiji we compared visitation rates of rats and mongooses at bait stations and measured biomass of leaf-litter invertebrates to assess the relative predation pressure from these species in forest areas at different distances from the forest edge. Forest areas over 5 km from the forest edge had significantly fewer baits encountered by rats or mongooses than did natural forest areas nearer agricultural and urban habitats. Remote forest areas may function as a last refuge for island species threatened by predation from non-native rats and mongooses. The biomass of leaf-litter invertebrates in remote forest areas was higher, indicating a refuge effect for some taxa targeted by rats and mongooses. Protecti...
The role of odour in Australian mammalian predator/prey interactions
2005-01-01
Odour plays an important role in many predator/prey interactions. In the northern hemisphere, many mammalian prey species have been shown to respond to predator odours. It is also widely assumed that mammalian predators utilise odours to locate their prey. This thesis explores the importance of odour in Australian mammalian predator/prey interactions. Responses of native Australian species to the faecal odour of two predators; the native tiger quoll Dasyurus maculatus and the introduced red fox Vulpes vulpes, were evaluated through live-trapping and focussed behavioural studies of captive animals. Tiger quoll responses to prey olfactory cues were investigated in a captive experiment. Native rodents (bush rats Rattus fuscipes, swamp rats R. lutreolus and eastern chestnut mice Pseudomys gracilicaudatus) equally avoided traps scented with either quoll or fox faeces, and in captive experiments, bush rats and swamp rats reduced their average speed in response to both predator odours. Of the marsupial species, northern brown bandicoots Isoodon macrourus and common brushtail possums Trichosurus vulpecula were captured more frequently in quoll-scented traps than unscented traps or foxscented traps, while captures of brown antechinus Antechinus stuarttii, long-nosed bandicoots Perameles nasuta and southern brown bandicoot I. obesulus were unaffected by the either predator odour. In captive experiments, brown antechinus, long-nosed and northern brown bandicoots decreased their foraging in response to both predator odours, and spent less time in areas scented with quoll faeces. Tiger quolls didn't appear to detect odour sources from a distance of >65 cm, but they did follow scent trails and spent more time in areas scented with the urine and faeces of potential prey. Chemical analysis revealed no common components in fox and quoll odour which prey species could be responding to. Therefore, these native species have evolved to respond to fox odour since foxes were introduced to Australia 130 years ago. The stronger response of native rodents to fox odour may be a legacy of their co-evolution with canid predators prior to entering Australia. A better understanding of how odour is utilised in Australian predator/prey interactions may lead to a greater ability to protect Australia's unique mammalian fauna from introduced predators. Publisher: Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences Language: EN Rights: Copyright Benjamin Gallard Russell; http://unsworks.unsw.edu.au/copyright
Human-dominated habitats and helminth parasitism in Southeast Asian murids
2010-01-01
The effect of habitat anthropization is investigated using a comparative analysis based on a literature survey of the gastrointestinal helminths of murid rodents described in Southeast Asia (SEA). The literature survey gave 30 references on helminth diversity concerning 20 murid rodent species. The diversity of helminths was high with a total of 13 species of cestodes, 15 species of trematodes, 29 species of nematodes and one species of acanthocephalans. The highest helminth species richness was found in Rattus tanezumi, Rattus norvegicus and Rattus argentiventer, all these species were found in more human-dominated habitats (agricultural areas or human settlements). Helminth species richness was positively linked across rodent species to the level of the anthropization of the host environ...
The mammals of Parker River Inlet National Park, Otway National Park
2002-01-01
Studies of small mammals at Parker River Inlet from 1985-95 have demonstrated the presence of ten species of small mammals. Trapping, spotlighting and incidental sightings have shown that a further 18 species of mammals occur within an area of 200 ha. Pseudomys fumeus and Antechinus minimus, recorded in this survey, are rare and restricted in Victoria. The species richness of the area is related to the heterogeneity of the vegetation, with twelve vegetation types being identified in the study area. The occurrence of the more abundant small mammals, Rattus fuscipes, Rattus lutreolus, Mus musculus and Antechinus swainsonii, is correlated with vegetation structure and floristics. Causes of fluctuations of the populations of the exotic species M. musculus and Rattus rattus are considered. Management recommendations, which reflect the high significance of faunal habitat in the area, are made with the aim of minimising human impact. Publisher: ; The Field Naturalist Club of Victoria Relation: The Victorian Naturalist Vol. 119, no. 2 (2002), p. 60-68 Other identifier: ; ISSN 0042-5184 Coverage: Language: Rights: Copyright The Field Naturalist Club of Victoria
Revisiting the taxonomy of the Rattini tribe: a phylogeny-based delimitation of species boundaries
Full Text Available.BackgroundRodents are recognized as hosts for at least 60 zoonotic diseases and may represent a serious threat for human health. In the context of global environmental changes and increasing mobility of humans and animals, contacts between pathogens and potential animal hosts and vectors are modified, amplifying the risk of disease emergence. An accurate identification of each rodent at a specific level is needed in order to understand their implications in the transmission of diseases. Among the Muridae, the Rattini tribe encompasses 167 species inhabiting South East Asia, a hotspot of both biodiversity and emerging and re-emerging diseases. The region faces growing economical development that affects habitats, biodiversity and health. Rat species have been demonstrated as significant hosts of pathogens but are still difficult to recognize at a specific level using morphological criteria. DNA-barcoding methods appear as accurate tools for rat species identification but their use is hampered by the need of reliable identification of reference specimens. In this study, we explore and highlight the limits of the current taxonomy of the Rattini tribe.ResultsWe used the DNA sequence information itself as the primary information source to establish group membership and estimate putative species boundaries. We sequenced two mitochondrial and one nuclear genes from 122 rat samples to perform phylogenetic reconstructions. The method of Pons and colleagues (2006) that determines, with no prior expectations, the locations of ancestral nodes defining putative species was then applied to our dataset. To give an appropriate name to each cluster recognized as a putative species, we reviewed information from the literature and obtained sequences from a museum holotype specimen following the ancient DNA criteria.ConclusionsUsing a recently developed methodology, this study succeeds in refining the taxonomy of one of the most difficult groups of mammals. Most of the species expected within the area were retrieved but new putative species limits were also indicated, in particular within Berylmys and Rattus genera, where future taxonomic studies should be directed. Our study lays the foundations to better investigate rodent-born diseases in South East Asia and illustrates the relevance of evolutionary studies for health and medical sciences.
Full Text Available.BackgroundThe draft mouse (Mus musculus) genome sequence revealed an unexpected proliferation of gene duplicates encoding a family of secretoglobin proteins including the androgen-binding protein (ABP) α, β and γ subunits. Further investigation of 14 α-like (Abpa) and 13 β- or γ-like (Abpbg) undisrupted gene sequences revealed a rich diversity of developmental stage-, sex- and tissue-specific expression. Despite these studies, our understanding of the evolution of this gene family remains incomplete. Questions arise from imperfections in the initial mouse genome assembly and a dearth of information about the gene family structure in other rodents and mammals.ResultsHere, we interrogate the latest 'finished' mouse (Mus musculus) genome sequence assembly to show that the Abp gene repertoire is, in fact, twice as large as reported previously, with 30 Abpa and 34 Abpbg genes and pseudogenes. All of these have arisen since the last common ancestor with rat (Rattus norvegicus). We then demonstrate, by sequencing homologs from species within the Mus genus, that this burst of gene duplication occurred very recently, within the past seven million years. Finally, we survey Abp orthologs in genomes from across the mammalian clade and show that bursts of Abp gene duplications are not specific to the murid rodents; they also occurred recently in the lagomorph (rabbit, Oryctolagus cuniculus) and ruminant (cattle, Bos taurus) lineages, although not in other mammalian taxa.ConclusionWe conclude that Abp genes have undergone repeated bursts of gene duplication and adaptive sequence diversification driven by these genes' participation in chemosensation and/or sexual identification.
2009-12-01
Full Text Available.To understand the prevalence of Cryptosporidium infection in rodents in China and to assess the potential role of rodents as a source for human cryptosporidiosis, 723 specimens from 18 rodent species were collected from four provinces of China and examined between August 2007 and December 2008 by microscopy after using Sheather's sugar flotation and modified acid-fast staining. Cryptosporidium oocysts were detected in 83 specimens, with an overall prevalence of 11.5%. Phodopus sungorus, Phodopus campbelli, and Rattus tanezumi were new reported hosts of Cryptosporidium. The genotypes and subtypes of Cryptosporidium strains in microscopy-positive specimens were further identified by PCR and sequence analysis of the small subunit rRNA and the 60-kDa glycoprotein (gp60) genes. In addition to Cryptosporidium parvum, C. muris, C. andersoni, C. wrairi, ferret genotype, and mouse genotype I, four new Cryptosporidium genotypes were identified, including the hamster genotype, chipmunk genotype III, and rat genotypes II and III. Mixed Cryptosporidium species/genotypes were found in 10.8% of Cryptosporidium-positive specimens. Sequence analysis of the gp60 gene showed that C. parvum strains in pet Siberian chipmunks and hamsters were all of the subtype IIdA15G1, which was found previously in a human isolate in The Netherlands and lambs in Spain. The gp60 sequences of C. wrairi and the Cryptosporidium ferret genotype and mouse genotype I were also obtained. These findings suggest that pet rodents may be potential reservoirs of zoonotic Cryptosporidium species and subtypes.
Forensic taphonomy: processes associated with cadaver decomposition in soil
2005-01-01
A series of laboratory and field incubations were carried out where juvenile rat (Rattus rattus) cadavers were buried in three soils of contrasting texture from tropical savanna ecosystems in Queensland, Australia. This work was done in order to develop an understanding of the effect of environmental variables (temperature, moisture), the soil in which a cadaver is buried and the nature of the cadaver on the processes associated with cadaver decomposition in soil. A pattern of mass loss comprised of an “Early Phase” of slow mass loss, “Intermediate Phase” of rapid mass loss and a “Late Phase” of slow mass loss. Early Phase decomposition coincided with an initial increase in carbon dioxide (CO2) evolution, microbial biomass carbon (Cmic), phosphodiesterase activity, protease activity and soil pH. Microbial activity was triggered within 24 hours of cadaver burial and this initial flush of activity was likely due to both soil-borne and cadaveric microbes. Intermediate Phase decomposition was typically associated with peak levels of CO2 evolution, Cmic, phosphodiesterase activity and soil pH. Late Phase decomposition typically coincided with a slowing down of process rates. In some cases, however, peak levels of protease activity were observed during late phase decomposition. The rate of cadaver decomposition increased with an increase in temperature and moisture. However, the rate of cadaver decomposition was slowed at a matric potential of –0.3 megapascals (MPa) in coarse-textured soil and a matric potential of –0.01 MPa in fine-textured soil. Temperature and moisture also had similar effects on CO2 evolution, Cmic, protease activity, phosphodiesterase activity and soil pH. In addition, the soil matrix and the soil microbial biomass had a significant effect on cadaver decomposition. The rate of cadaver decomposition following burial in soil was greater than when a cadaver was exposed to a sterile, soil-free environment. Furthermore, cadaver decomposition was greatest in sandy soil. These phenomena were likely due to a greater rate of gas diffusion associated with sandy soil and the activity of aerobic microorganisms. The activity of aerobic decomposers was reflected as a significant relationship between CO2 evolution and cadaver mass loss. The structure of the soil microbial community determined by analysis of phospholipid fatty acids (PLFAs) was affected by the presence of a cadaver. However, soil type and seasonal variation in temperature and moisture had a much greater effect on the soil microbial community. In addition, the current study provided more evidence to show that the structure of the soil microbial community can be related to the function (protease, phosphodiesterase activity) of the soil microbial community. Furthermore, temporal changes in the microbial community of gravesoils were also observed. Te results from the laboratory incubations were used to interpret the results from the field incubations. However, some results differed between laboratory and field settings. The rate of cadaver mass loss was greater in a field setting. Also, cadaver decomposition was greatest in sandy soil in the laboratory while cadaver mass loss was greatest in clay soil in the field. Moreover, changes in soil pH and the concentration of ammonium were less in a field setting. The current thesis has demonstrated that the introduction of a cadaver into the soil can have a significant effect on the biological and chemical characteristics of soils. In turn, this phenomenon can be affected by environmental variables, the soil in which a cadaver is placed and the nature of the cadaver. Biological and chemical measurements conducted in the current study hold potential for forensic applications, including markers of clandestine graves and a basis for the estimation of postmortem and postburial intervals. Format: application/pdf Other identifier: Carter, David O. (2005) Forensic taphonomy: processes associated with cadaver decomposition in soil. PhD thesis, James Cook University.
2009-01-01
Declines and extinctions of amphibian populations are a global dilemma with complex local causes, which should be viewed in the context of a much larger biodiversity crisis. As other animal groups, amphibians with restricted distributions, such as island endemics, are thought to be more vulnerable to environmental change and susceptible to population declines. In the New Zealand archipelago, the only four native species of frogs (Leiopelma hochstetteri, L. archeyi, L. hamiltoni and L. pakeka) are classified as threatened. In particular Leiopelma hochstetteri, the most widespread and abundant endemic frog species in New Zealand, now survives only in spatially fragmented populations as a result of direct or indirect human activity. Hence, it is recognised as threatened and fully protected by legislation. In the last fifty years, some L. hochstetteri populations have been studied, providing descriptive information, which may be used to assess the current status (increasing, stable or declining) of previously or never monitored populations. This thesis examines the diet and trophic level, the effects ship rats (Rattus rattus) as well as the distribution and abundance of L. hochstetteri on a habitat-use context, to provide a basis for evaluating conceivable decline-agents, and to establish a platform to design directed conservation strategies. The Waitakere Ranges are considered a Leiopelma hochstetteri conservation management unit, on which L. hochstetteri has been previously studied. This area consists of a series of hills that run roughly north–south, which are mostly covered in regenerating indigenous vegetation. Today, 60% of the Waitakere Ranges fall within a Regional Park, which together with its surrounding residential areas is afforded protection to minimise the effects of development on the region. The accessibility and conservation character of this area makes it an ideal area for the study of L. hochstetteri populations. As a first step to characterise the diet and trophic level of L. hochstetteri within streams in the Waitakere Ranges, Auckland, stable carbon and nitrogen isotope analyses were undertaken on a variety of sympatric terrestrial and aquatic plant and animal species, including adult frogs. These results showed that: 1) aquatic and terrestrial food webs were linked by terrestrial inputs into the stream; 2) invertebrate and vertebrate predators separated well into distinct trophic groups; and 3) L. hochstetteri occupied an intermediate trophic position among predators, with a diet, at least as an adult, comprising terrestrial invertebrates. Shortfin eels and banded kokopu were identified as potential predators of L. hochstetteri, but data for rats were inconclusive. The inconclusiveness of these trophic studies, with regard to the effects of ship rats on L. hochstetteri populations, lead me to evaluate the influence of a seven-year ship rat management operation on frog abundance. To achieve a reliable evaluation, the habitat characteristics that had significant influence on frog abundance were identified. Then, it was confirmed that the study areas represented similar habitats in terms of those variables, and finally the effect of the pest-management activities was evaluated. Presence/absence of pest-management operations did not have a significant effect on frog abundance. These results, together with the results of the diet and trophic level analyses, suggested that ship rats do not represent a significant threat for this frog species, at least in the Waitakere Ranges. The results of distribution and abundance investigations indicated that in the Waitakere Ranges frogs are currently widely distributed, relatively abundant and that recruitment has occurred at least in the last ten years. Additionally, in order to identify associations between habitat characteristics and frog distribution and abundance, reliable and specifically designed monitoring methodologies were developed. Although this frog is known to occur in wet areas adjacent to shaded streams in forested catchments, quantitative ecological data previously did not exist to enable characterisation of its habitat. Here, novel data were reported on the current distribution and habitat requirements of this species in the Waitakere Ranges. Statistical modelling demonstrates frogs most likely occur in small, erosive streams with coarse substrates and cold waters, surrounded by mature or undisturbed riparian vegetation, where higher abundances of frogs may be found in steep areas with stable patches of cobbles and boulders lying against larger stream bed elements within the stream channel. Anthropogenic activities, such as clearing or logging, and upstream disturbances that potentially increase silt input into streams were identified as threats to these frog species. Finally, the habitat-use information gathered during this investigation was utilised to develop a spatial decision support system (SDSS) as a tool to assess the quality and quantity of habitat available to L. hochstetteri populations associated with the Auckland Region. These results have important implications for the conservation of New Zealand native frog species and riparian stream habitat. Language: en
Recent cases of eosinophilic meningitis in Hawaii have drawn attention to a food-borne parasitic infection that occurs in Hawai`i, the Pacific Islands, southern and eastern Asia, and elsewhere. In late 2008, the Hawai`i Department of Health reported that four people on the island of Hawai`i had bee...
1992-06-01
Studies have been conducted at Battelle, Pacific Northwest Laboratory, to examine extremely-low-frequency (ELF) electromagnetic fields for possible biological effects in animals. Three areas of investigation are reported here: (1) studies on the nervous system, including behavior and neuroendocrine function, (2) experiments on cancer development in animals, and (3) measurements of currents and electric fields induced in animal models by exposure to external magnetic fields. In behavioral experiments, rats have been shown to be responsive to ELF electric field exposure. Furthermore, experimental data indicate that short-term memory may be affected in albino rats exposed to combined ELF and static magnetic fields. Neuroendocrine studies have been conducted to demonstrate an apparent stress-related response in rats exposed to 60-Hz electric fields. Nighttime pineal melatonin levels have been shown to be significantly depressed in animals exposed to either electric or magnetic fields. A number of animal tumor models are currently under investigation to examine possible relationships between ELF exposure and carcinogenesis. Finally, theoretical and experimental measurements have been performed which form the basis for animals and human exposure comparisons.
ELF electric and magnetic fields: Pacific Northwest Laboratory studies
1992-06-01
Studies have been conducted at Battelle, Pacific Northwest Laboratory, to examine extremely-low-frequency (ELF) electromagnetic fields for possible biological effects in animals. Three areas of investigation are reported here: (1) studies on the nervous system, including behavior and neuroendocrine function, (2) experiments on cancer development in animals, and (3) measurements of currents and electric fields induced in animal models by exposure to external magnetic fields. In behavioral experiments, rats have been shown to be responsive to ELF electric field exposure. Furthermore, experimental data indicate that short-term memory may be affected in albino rats exposed to combined ELF and static magnetic fields. Neuroendocrine studies have been conducted to demonstrate an apparent stress-related response in rats exposed to 60-Hz electric fields. Nighttime pineal melatonin levels have been shown to be significantly depressed in animals exposed to either electric or magnetic fields. A number of animal tumor models are currently under investigation to examine possible relationships between ELF exposure and carcinogenesis. Finally, theoretical and experimental measurements have been performed which form the basis for animals and human exposure comparisons.
Aspects of the ecology and management of small mammalian predators in northern New Zealand
1998-01-01
Each chapter in this thesis has been written as a separate paper intended for later publication. Rather than write one summary, an abstract for each chapter has been given in the order they are presented in the thesis. Chapter I. The prey species of domestic cats (Felis catus) in two suburbs of Auckland city, New Zealand. The prey brought in by 80 cats (Felis catus), over a year was monitored in two suburbs of Auckland New Zealand. The survey technique followed that of Churcher & Lawton (1987) where cat owners were asked to record (and if possible keep) the prey their cats brought in. The results for the year indicated that there were distinct differences in the type of prey taken by cats in each area. Rodents were the most important prey brought in by domestic cats in an urban / forest fringe habitat and invertebrates were the main prey brought in by domestic cats in a fully urban habitat. Birds and lizards were the second and third most important prey groups in both study areas. Rat and mouse snap trap indexes which were run at each study location, did not detect rodents in the urban habitat. The results from the urban/forest fringe concurred more with studies of feral cat diet in New Zealand whilst those from the urban area compared more to studies of domestic and stray cat diet in urban areas overseas. There were seasonal trends in the prey captured in each area and in both areas cats hunted less over the winter months. Chapter II. Diets of coexisting alien mammalian carnivores in Northern New Zealand. 120 feral cats, 85 stoats (Mustela erminea), 28 weasels (M. nivalis) and 16 ferrets (M. furo) were caught over three years, in Northland, New Zealand. The gut contents of these animals were examined and their food habits described. The main prey groups of cats were (in order of importance by weight), lagomorphs, rodents (Rattus spp & Mus musculus), other mammals, birds and invertebrates. The main prey of stoats were rodents, birds, lagomorphs, skinks (Cyclodina spp) and invertebrates. Skinks, followed by mice, were the main prey of weasels. Rabbits (Oryctolagus cuniculus) were the most commonly occurring prey item in the ferret guts. The food habits for cats and stoats were compared between different habitats within the Northland region where these animals were collected from. There was little difference between habitats, but invertebrates occurred more frequently and lagomorphs less frequently in the diet of animals from forest habitats compared to those from forest / pasture and coastal habitats. No differences were found in the prey of male and female cats, but invertebrates occurred more frequently in the guts of sub-adult cats compared to adult cats. Skinks occurred more frequently in the guts of female stoats, which tended to take smaller prey items than males. Chapter III. Home range of introduced mammalian carnivores, feral cats (Felis catus), stoats (Mustela erminea) and a ferret (M. furo) at Trounson Kauri Park, Northland, New Zealand. The minimum home ranges of eleven feral cats, four stoats and one male ferret were examined by radio telemetry at Trounson Kauri Park in Northland New Zealand. The average minimum home range of male feral cats was 305 ± 74ha. This was not significantly larger than the 122 ± 35 ha minimum average home range of female cats. The minimum average home range of three male stoats was 108 ± 19 ha and the minimum home range of one female stoat was 50 ha. The male ferret had a minimum home range of 179 ha. There was no overlap spatially, in the home range of three adult male cats. There was also very little spatial overlap in the home range of four female cats. There was substantial home range overlap with four sub-adult male cats. The home ranges of these sub-adult male cats also overlapped spatially with those of the adjacent females and adult males. The home ranges of two male stoats overlapped spatially to some degree and the home range of another male stoat overlapped that of the female stoat substantially. The home range of the male ferret overlapped the home ranges of all of the cats occupying similar areas of the park. The home ranges of two male stoats overlapped the home ranges of the adjacent cats but not into the "core" areas of those cats ranges. Chapter IV. Secondary poisoning of introduced mammalian carnivores during possum and rodent control operations at Trounson Kauri Park, Northland New Zealand. Predatory mammals were monitored by radio telemetry through a 1080 then brodifacoum poison baiting operation at Trounson Kauri Park in Northland, New Zealand to target possums (Trichosurus vulpecula) and rodents (Rattus rattus, Rattus norvegicus & Mus musculus). All six feral cats (Felis catus), and the single stoat (Mustela erminea) and ferret (Mustela furo) being monitored at the beginning of the operation died of secondary poisoning following the 1080 operation. A further two cats and four stoats were radio tagged and monitored through the ongoing poisoning campaign using brodifacoum in a continuous baiting regime. None of these radio tagged carnivores died of secondary poisoning. However, tissue analysis of additional carnivores trapped at Trounson found that cats, weasels (Mustela nivalis) and to a lesser extent stoats did contain brodifacoum residues. The duration that the radio tagged predators were alive in and around Trounson Kauri Park suggested that the secondary poisoning effect was much reduced under the continuous baiting strategy, compared to the initial 1080 poison operation. Chapter V. Managing alien mammals in mainland New Zealand: The implications for predator/prey interactions in complex communities. Recent advancements in alien pest mammal control technologies have enabled conservation managers to attempt long term, large scale, predator and browser control programmes at mainland sites in New Zealand. At Trounson Kauri Park (in Northland, New Zealand) feral cats, ferrets, stoats and weasels plus rodents and possums were controlled for two and a half years. Early results from Trounson suggested that some native birds and plants responded positively and quickly to the control of these alien pest mammals. However, the management also affected the predator-prey and predator-predator interactions, within the mammalian community, with changes in the predator guild and some prey species increasing in abundance. The long term effects of these responses within the mammalian community to control efforts are unclear. A review of the international literature served only to confirm the view that managing alien mammals where re-invasion is constant will be a complex task. Conservation management at mainland sites like Trounson Kauri Park, may in effect be acting as crude mammalian predator removal experiments. Monitoring changes in predator-prey interactions and predator-predator interactions at this and other intensive management sites over sufficient time frames could provide scientists with the critical ecological data required to construct useful predictive models. The ability of managers to target specific pests at critical times would represent a significant advancement in controlling predatory mammals on the New Zealand mainland. Publisher: ResearchSpace@Auckland Language: en Rights: Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated.; http://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm; Copyright: The author
Breeding productivity of Smith Island black ducks
We investigated the breeding performance of American black ducks (Anas rubripes) on Smith Island, Chesapeake Bay, to improve our understanding of island black duck breeding ecology and to make management recommendations to enhance productivity. During 1995-96, we implanted 56 female black ducks with 20-g radio transmitters and tracked 35 of the individuals through the breeding season to locate nests, determine nest fate, and identify brood habitat. We also increased preseason banding efforts and compared capture characteristics over 12 years with those from the Deal Island Wildlife Management Area, a banding site on the mainland of Tangier Sound. A low rate of nesting (37%), lack of renesting, and poor hatching success (31%) indicated that island salt marsh habitats present a harsh environment for breeding black ducks. Black ducks located 11 of 13 nests (85%) in black needlerush (Juncus roemerianus) marsh where they were vulnerable to flooding from extreme tides and to egg predators. No nests were found on forested tree hammocks, a feature that distinguishes Smith Island from nearby South Marsh and Bloodsworth Islands. Nest predators included red foxes (Vulpes vulpes), herring gulls (Larus argentams), fish crows (Corvus ossifragus), and, potentially, Norway rats (Rattus norvegicus). Unlike mainland red foxes, foxes radio tracked on Smith Island were found to be capable swimmers and effective low marsh predators. We found shoreline meadows of widgeon grass (Ruppia maritima) to be important foraging sites for black ducks and suspected that the virtual absence of fresh water in this high salinity environment (1217+ ppt) to incur some cost in terms of growth and survival of ducklings. Preseason bandings revealed a high proportion of banded adults and a strong positive correlation in age ratios with the Deal Island banding site. This latter finding strongly suggests a negative universal effect of storm tides on nest success for Tangier Sound black ducks. Management to reduce nest predators, especially gulls and foxes, likely will have the greatest immediate benefit for island breeding black ducks.
Adhesion of streptococcus rattus and streptococcus mutans to metal surfaces
1988-01-01
The adhesion of Streptococcus rattus BHT and Streptococcus mutans IB to metal specimens of amalgam, silver, tin and copper was studied using (6-/sup 3/H) thymidine labeled cells. In the standard assay the metal specimens were suspended by a nylon thread in an adhesion solution containing a chemically defined bacterial growth medium (FMC), sucrose, and radiolabeled bacteria. Maximum amounts of adhering bacteria were obtained after about 100 min of incubation. Saturation of the metal specimens with bacteria was not observed. Both strains also adhered in the absence of sucrose, indicating that glucan formation was not necessary for adhesion. However, in the presence of glucose, adhesion was only 26-45% of that observed in the presence of equimolar sucrose. Sucrose-dependent stimulation of adhesion seemed to be due to increased cell-to-cell adhesion capacity. Isolated radiolabeled water-insoluble and water-soluble polysaccharides produced from sucrose by S. rattus BHT were not adsorbed to the metal surfaces.
Molecular evolution of Trichuris muris isolated from different Muridae hosts in Europe
2010-01-01
A phylogeographic study was carried out of Trichuris muris, nematode parasitizing Murinae rodents from the Muridae family, isolated from four different hosts and from different geographical regions of Europe by amplification and sequencing of the ITS1-5.8S-ITS2 fragment of the ribosomal DNA. T. muris was found in the Apodemus sylvaticus, Apodemus flavicollis, Mus domesticus, and Rattus rattus rodents. The molecular results confirm the presence of DNA polymorphisms among T. muris isolates from Europe. The present study shows two clear-cut geographical and genetic lineages: one of them is widespread from northern Spain (Catalonia) to Denmark (Western European region), while the second is widespread in the Eastern European region (Croatia, Rumania, and Turkey). These two genotypes can be easi...
Detection of Bartonella spp. in wild rodents in Israel using HRM real-time PCR
2009-01-01
The prevalence of Bartonella spp. in wild rodents was studied in 19 geographical locations in Israel. One hundred and twelve rodents belonging to five species (Mus musculus, Rattus rattus, Microtus socialis, Acomys cahirinus and Apodemus sylvaticus) were included in the survey. In addition, 156 ectoparasites were collected from the rodents. Spleen sample from each rodent and the ectoparasites were examined for the presence of Bartonella DNA using high resolution melt (HRM) real-time PCR. The method was designed for the simultaneous detection and differentiation of eight Bartonella spp. according to the nucleotide variation in each of two gene fragments (rpoB and gltA) and the 16S-23S intergenic spacer (ITS) locus, using the same PCR protocol which allowed the simultaneous amplification of ...
Adhesion of streptococcus rattus and streptococcus mutans to metal surfaces
1988-01-01
The adhesion of Streptococcus rattus BHT and Streptococcus mutans IB to metal specimens of amalgam, silver, tin and copper was studied using (6-3H) thymidine labeled cells. In the standard assay the metal specimens were suspended by a nylon thread in an adhesion solution containing a chemically defined bacterial growth medium (FMC), sucrose, and radiolabeled bacteria. Maximum amounts of adhering bacteria were obtained after about 100 min of incubation. Saturation of the metal specimens with bacteria was not observed. Both strains also adhered in the absence of sucrose, indicating that glucan formation was not necessary for adhesion. However, in the presence of glucose, adhesion was only 26-45% of that observed in the presence of equimolar sucrose. Sucrose-dependent stimulation of adhesion seemed to be due to increased cell-to-cell adhesion capacity. ...
2010-01-01
The aim of this research was to compare the abundance, growth, age structure and reproductive patterns of Rattus norvegicus and Mus musculus populations of a shanty town and a parkland in the city of Buenos Aires, Argentina. Live trapping of rodents was conducted in each area every 2 months, from September 2006 to August 2007. Abundance of R. norvegicus and M. musculus was significantly higher in the shanty town than in the parkland. Abundance of both species showed significant differences between trapping sessions in both study sites. Both species showed a peak in abundance in summer in the parkland and also in autumn in the shanty town. Age structure of both species differed between summer-autumn and winter-spring in the shanty town. In the parkland, pregnant females of both species were...
1998-01-01
Current epidemiological surveys in the Western Pacific area and Kii Peninsula have suggested that low calcium (Ca), magnesium (Mg), and high aluminum (Al) and manganese (Mn) in river, soil and drinking water may be implicated in the pathogenetic process of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia (PD). The condition of unbalanced minerals was experimentally duplicated in this study using rats. Male Wistar rats, weighing 200 g, were maintained for 60 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca diet with high Al. Magnesium concentration was determined in spinal cord and trabecular bone using inductively coupled plasma emission spectrometry (ICP) and the calcium concentration was determined using neutron activation method. In the group maintained on low Ca high Al diet, magnesium content of the spinal cord was lower than the group fed standard diet. Also, magnesium content of lumbar bone showed lower values in the unbalanced diet group fed low Ca high Al diet than those in the standard diet and low Ca diet groups. Calcium content of spinal cord was highest in rats maintained on low Ca high Al diet. Calcium content in lumbar bone of rats significantly decreased in rats maintained on the low Ca diet (group B and C) compared to rats given a standard diet (group A). Our data indicate that low Ca and high Al dietary intake influence Mg concentration in bone and central nervous system (CNS) tissues and that low Ca and high Al diet diminish Mg in bone and CNS tissues, thereby inducing loss of calcification in bone and degeneration of CNS tissues due to disturbance of the normal biological effects of Mg. (author)
2000-01-01
This study investigated the effects of consumption of Great Lakes fish on progressive ratio performance, and on the pattern and concentrations of brain polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethene (DDE), and mirex in the rat. Adult, male Sprague-Dawley rats were fed a 30% diet of either Lake Ontario salmon (LAKE), Pacific Ocean salmon, or lab chow control for 20 or 65 days. Following the treatment regimen, half the rats from each group were sacrificed immediately for gas chromatographic analysis of organochlorine contaminants, and the other half were tested on a multiple fixed-ratio-progressive-ratio reinforcement schedule and then sacrificed for analysis. Consumption of Lake Ontario fish resulted in significantly higher levels of brain PCBs, DDE, and mirex relative to controls, but still well within human exposure ranges. Consumption of Lake Ontario fish for 20 or 65 days produced an average brain PCB concentration of 457 and 934 ng/g fat, respectively. Consumption of laboratory rat chow or Pacific Ocean salmon for 20 or 65 days produced an average brain PCB concentration of 240, 464, and 441 ng/g fat, respectively. Moreover, both LAKE-fed groups showed a much more heavily chlorinated pattern of brain PCBs than all control groups, as evidenced by both significant increases in the most heavily chlorinated PCB congeners and significant increases in the average chlorine biphenyl.
1998-01-01
Current epidemiological surveys in the Western Pacific area and Kii Peninsula have suggested that low calcium (Ca), magnesium (Mg), and high aluminum (Al) and manganese (Mn) in river, soil and drinking water may be implicated in the pathogenetic process of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia (PD). The condition of unbalanced minerals was experimentally duplicated in this study using rats. Male Wistar rats, weighing 200 g, were maintained for 60 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca diet with high Al. Magnesium concentration was determined in spinal cord and trabecular bone using inductively coupled plasma emission spectrometry (ICP) and the calcium concentration was determined using neutron activation method. In the group maintained on low Ca high Al diet, magnesium content of the spinal cord was lower than ...
As in Alzheimer's disease, brains of Guam Chamorros with amyotrophic lateral sclerosis (ALS) and Parkinsonism-dementia complex (PDC) contain intraneuronal-paired helical filaments composed of accumulated phosphorylated tau protein. Tau mRNA expression in rat neuronal cultures-normally modulated by glutamate-increases after treatment with the aglycone of cycasin, a cycad-derived toxin whose concentration in Chamorro food varies with disease incidence. Elevated Tau gene expression in vitro is coincident with increased cycasin-related DNA adducts and reduced DNA repair. Cycasin and endogenous glutamate may together promote the accumulation of tau protein and neuronal degeneration in Western Pacific ALS/PDC.
Mid-Pacific Marine Laboratory. Annual report for the period, 1 October 1977--30 September 1978
1979-03-01
Studies on behavior included reproduction and sociobiology of reef fishes and aggression, hearing, and ultrasonic telemetry in sharks. Ecological studies included population, growth, and mortality studies on birds, corals, crustacea, echinoderms, fishes, molluscs, and rats. Geochemistry studies included biogeochemistry of reef organisms and hydrogeochemistry of groundwater. Geology studies included bioerosion of sea urchins, biology of endolithic processes, and survey of soils. Oceanography studies were conducted on lagoon circulation. Physiological studies were conducted on symbiosis in corals and utilization of organic material by Foraminifera. Studies on systematics of algae, echinoderms, and fishes were conducted. (HLW)
2010-01-01
The Ouva Parakeet (Eunymphicus uvaeensis), endemic to Ouva Island (Loyalty Islands, New Caledonia, south-west Pacific), is a rainforest bird that is dependent on tree cavities for nesting. It is threatened by deforestation, but also by competition for nest sites with introduced bees, harvesting for pets, and potentially predation by introduced species. Despite these threats, we show that the Ouva Parakeet population increased exponentially from an estimated 617 (274996) birds in 1993 to 2,090 (1,2803,413) birds in 2009 (95% confidence interval). We explain this population increase by community-based protection measures that eliminated nest poaching. We recommend that these measures are maintained, remnant forest is protected, and the introduction of rats is prevented.
Pigs are the most important animal reservoir for Tunga penetrans (jigger flea) in rural Nigeria
2008-01-01
We examined the domestic animals and rodents in a community in rural Nigeria. Of the 133 animals examined, 29 (21.8%) were infested, the highest prevalence of infestation and highest parasite load was found in the pigs (prevalence 54.8%, median = nine embedded parasites), followed by dogs (45.5%; median = 4), Rattus rattus (29.4%; median = 2) and Mus minutoides (15.4%; median = 1.5). Of all the tungiasis lesions identified 83% were found in pigs. Our data confirm that tungiasis is a zoonotic disease, and that pigs are its most important animal reservoir in this endemic community. Publisher: Royal Society of Medicine Press Format: application/pdf Other identifier: Ugbomoiko, Uade s., Ariza, Liana, and Heukelbach, Jorg (2008) Pigs are the most important animal reservoir for Tunga penetrans (jigger flea) in rural Nigeria. Tropical Doctor, 38 (4). pp. 266-227. ISSN 1758-1133
1995-10-20
A marine bacterium, judged as a new species close to Shewanella putrefaciens, was isolated from the intestinal contents of the Pacific mackerel. The isolated strain SCRC-2728 produced EPA as a sole polyunsaturated fatty acid amounting to 25-40 % of the total fatty acid in the cells. EPA existed as phospholipids in the cell and was found in the sn-2-position of phosphatidyl ethanolamine and phosphatidyl glycerol. The physiological activity of the EPA-phospholipids extracted from SCRC-2738 cells was examined following administration to stroke-prone spontaneously hypertensive rats. After four weeks of oral administration, serum lipids (cholesterol, triacylglycerol and phospholipid) and the systolic blood pressure were reduced significantly, compared to the control rats fed soybean lecithin. Moreover, we observed a significant reduction of the weight of perirenal and paraepididymal adipose tissues (26-38 %). The 38 kbp genom DNA fragment was cloned from SCRC-2738 and expressed in Escherichia coli, which resulted in the production of EPA. The nucleotide sequence of the 38 kbp DNA fragment was determined. The DNA fragment contains eight open reading frames, and three of them possess homology with enzymes involved in fatty acid synthesis. 18 refs., 9 figs., 2 tabs.
Magnesium/calcium related neurological disorders in the ALS focus of the Kii Peninsula
1997-01-01
Current epidemiological surveys in the Western Pacific area and Kii Peninsula have suggested that low calcium(Ca), magnesium(Mg) and high aluminum(Al) and manganese(Mn) in river, soil and drinking water may be implicated in the pathogenetic process of amyotrophic lateral sclerosis(ALS) and Parkinsonism-dementia(PD). The condition of unbalanced minerals was experimentally mimicked in this study using rats. Male Wistar rats, weighing 200 g, were maintained for 90 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca-Mg diet, (D) low Ca-Mg diet with high Al. In the groups maintained on unbalanced mineral diets, Ca and Mg contents of the bones were lower than standard diet. On the other hand, Ca content of CNS showed higher values in the unbalanced diet groups than those in the standard diet group. This was determined by neutron activation analysis(NAA) at ...
21 CFR 161.170 - Canned Pacific salmon.
...161.170 Canned Pacific salmon. (a) Identity. (1) Canned Pacific salmon is the food prepared...Oncorhynchus tshawytscha Chinook, king, spring. Oncorhynchus...optional forms of canned Pacific salmon are processed from...
Evidence of lung cancer risk from animal studies
1988-03-01
Human epidemiological data provide the most important basis for assessing risks of radon exposures. However, additional insight into the nature of exposure-response relationships is provided by animal experimentation and dosimetric determinations. Animal studies have now been conducted for more than 50 years to examine the levels of pollutants in underground mines that were responsible for the respiratory effects observed among miners. This work has emphasized respiratory cancer and the interaction of radon with other agents, such as ore dust, diesel-engine-exhaust fumes and cigarette smoke. The more recent data on radon-daughter inhalation exposures were provided by two American research centers, The University of Rochester (UR) and the Pacific Northwest Laboratory (PNL), and by the Compagnie Generale des Matieres Nucleaires (COGEMA) laboratory in France. Approximately 2000 mice, 100 rats and 80 dogs were employed in the completed UR studies, begun in the mid 1950s; 800 hamsters, 5000 rats and 100 dogs in the ongoing PNL studies, begun in the late 1960s; and 10,000 rats in the ongoing COGEMA studies, also begun in the late 1960s. More complete updated biological effects, data resulting from chronic radon-daughter inhalation exposures of mice, hamsters, rats and beagle dogs were examined. Emphasis on the carcinogenic effects of radon-decay product exposure, including the influences of radon-daughter exposure rate, unattached fraction and disequilibrium, and co-exposures to other pollutants. Plausible values for the radon (radon-daughter) lifetime lung-cancer risk coefficients are also provided. 13 refs., 1 fig., 1 tab.
Dissolved neon in the Pacific and South Atlantic oceans
Neon isotope measurements carried out in the Pacific and South Atlantic Oceans show that the S. Atlantic Ne contents are higher than the Pacific contents and seem to be of atmospheric origin. The range of Ne concentration observed for the S. Pacific and N. Pacific waters (below 1 km) is (1.75-1.87) x 10/sup -4/ and (1.82-1.93) x 10/sup -4/ cc STP/kg respectively.
The role of rodents and shrews in the transmission of Toxoplasma gondii to pigs
2008-01-01
Inadequate rodent control is considered to play a role in Toxoplasma gondii infection of pigs. This issue was addressed in the current study by combining a 4-month rodent control campaign and a 7-month longitudinal analysis of T. gondii seroprevalence in slaughter pigs. Three organic pig farms with known rodent infestation were included in the study. On these farms, presence of T. gondii in trapped rodents was evaluated by real-time PCR. All rodent species and shrews investigated had T. gondii DNA in brain or heart tissue. Prevalence was 10.3% in Rattus norvegicus, 6.5% in Mus musculus, 14.3% in Apodemus sylvaticus and 13.6% in Crocidura russula. Initial T. gondii seroprevalence in the slaughter pigs ranged between 8% and 17% and dropped on the three farms during the rodent control campaig...
Redescription and surface ultrastructure of Pygidiopsis macrostomum (Digenea: Heterophyidae).
Pygidiopsis macrostomum Travassos, 1928, a poorly known species originally described from a single specimen from Rattus norvegicus (Erxleben, 1777) in Brazil, is redescribed on the basis of metacercariae from the mesenteries of naturally infected guppies Poecilia vivipara Bloch and Schneider, 1801 (Poeciliidae), and adults obtained from an experimental infection of hamsters. Pygidiopsis macrostomum is characterized by the absence of oral spines, vitellaria extending forward to ventral sucker, uterus reaching pharyngeal level, X-shaped excretory vesicle, and an oral sucker/acetabulum ratio of 1:0.8. The surface ultrastructure shows that the tegument of the metacercaria does not strongly differ from that of adults. The brush-shaped spines of P. macrostomum are similar to those reported for Pygidiopsis summa and Pygidiopsis ardeae, but no differences in spine shape were observed throughout the body.
Preliminary assessment of safety and effectiveness in humans of ProBiora3 , a probiotic mouthwash
2009-01-01
Abstract Aims: To conduct a pilot human clinical trial to assess the safety and to test the ability of a probiotic mouthwash, ProBiora3, to affect the levels of Streptococcus mutans and certain known periodontal pathogens in the mouth when administered twice daily over a period of 4 weeks. Methods and Results: The mouthwash contained three specific strains of naturally occurring oral bacteria and was tested at two dose levels: 106 and 108 colony forming units each of Strep. oralis strain KJ3sm, Strep. uberis strain KJ2sm, and the spontaneous lactic acid-deficient variant of Strep. rattus, strain JH145. Substantial decreases in the levels of the marker bacteria were observed. No safety issues were noted with the twice daily application of this mouthwash. Conclusions: Despite the small numbe...
1996-12-01
Full Text Available.Electron microscopy of zoocin A-treated sensitive streptococcus cells revealed cytoplasmic disruption and ultimately complete rupture of the cell wall. Culture viability and optical density were shown to decrease rapidly and simultaneously in Streptococcus pyogenes FF22 but less quickly in the relatively more resistant Streptococcus mutans 10449. Zoocin A was shown to cleave hexaglycine in a colorimetric cell-free microtiter assay system, and it is concluded that the killing action of zoocin A, like that of lysostaphin, is most probably the result of direct cleavage of the peptidoglycan cross-links in the cell wall. The relationship between sensitivity to zoocin A and the peptidoglycan cross-linkage structure of Streptococcus zooepidemicus, Lactococcus spp., S. pyogenes, Streptococcus gordonii, Streptococcus oralis, S. mutans, and Streptococcus rattus has been evaluated.
An invaded wet ecosystem in Central Italy: An arrangement and evidence for an alien food chain
2008-01-01
The aim of this work is to provide an account of alien species richness and composition in a remnant Mediterranean coastal wetland of Central Italy. Data were obtained from different taxa-specific methods, in 20012005 (terrestrial vertebrates) and in 2005 (fish, arthropoda, mollusca). Among the 353 species sampled, 17 (4.8 %) are aliens (7.1% if we consider only vertebrates).Data on abundance, introduction type and status of alien species are reported. A crustacean, Procambarus clarkii, a fish, Gambusia sp. and three rodents, Myocastor coypus, Rattus norvegicus and Mus domesticus are the naturalized invasive species that locally could constitute a threat on economic and ecological levels. Data on Agapornis nigrigenis and Quelea cardinalis represent the first records for Italy. We also r...
Transport Pathways for Asian Pollution Outflow Over the Pacific: Interannual and Seasonal Variations
The meteorological pathways contributing to Asian pollution outflow over the Pacific are examined with a global three-dimensional model analysis of CO observations from the Transport and Chemical Evolution over the Pacific ...
The North Pacific, a global backup generator for past climate change
2010-07-08
Toward the end of the last ice age, a major reorganization took place in the current system of the North Pacific with far-reaching implications for climate. About that time, the North Pacific branch of the conveyor belt ...
Super-rare 'elkhorn' coral found in Pacific
2010-07-28
An Australian scientist has discovered what could be the world's rarest coral in the remote North Pacific Ocean. The unique Pacific elkhorn coral was found while conducting underwater surveys of Arno atoll in the ...
Reverberations of the Pacific Warm Pool : Feature Articles - NASA ...
This body of water, which spans the western waters of the equatorial Pacific to the ... These oscillations may affect the climate in regions as far away as the southern ... zone above the ocean and alter the surrounding air currents. ... off the coast of South America, but spread out far into the central Pacific. ...
Reflective Teachers and Teacher Educators in the Pacific Region: Conversations with Us Not about Us
This article reports on a study of Pacific primary school teachers' and university lecturers' reflections on their involvement in the in-service Bachelor of Education degree programme offered at the regional University of the South Pacific (USP) in
Establishing bioinformatics research in the Asia Pacific
In 1998, the Asia Pacific Bioinformatics Network (APBioNet), Asia's oldest bioinformatics organisation was set up to champion the advancement of bioinformatics in the Asia Pacific. By 2002, APBioNet...Full Text Available
Experimental, statistical, and biological models of radon carcinogenesis
1991-09-01
Risk models developed for underground miners have not been consistently validated in studies of populations exposed to indoor radon. Imprecision in risk estimates results principally from differences between exposures in mines as compared to domestic environments and from uncertainties about the interaction between cigarette-smoking and exposure to radon decay products. Uncertainties in extrapolating miner data to domestic exposures can be reduced by means of a broad-based health effects research program that addresses the interrelated issues of exposure, respiratory tract dose, carcinogenesis (molecular/cellular and animal studies, plus developing biological and statistical models), and the relationship of radon to smoking and other copollutant exposures. This article reviews experimental animal data on radon carcinogenesis observed primarily in rats at Pacific Northwest Laboratory. Recent experimental and mechanistic carcinogenesis models of exposures to radon, uranium ore dust, and cigarette smoke are presented with statistical analyses of animal data. 20 refs., 1 fig.
Resources, population and migration in the Pacific: Connecting islands and rim
2009-01-01
Abstract This article examines international migration in the Pacific and argues that there should be still greater opportunities for the people of Pacific countries to migrate between their home states and the developed states of the Pacific Rim. The case for borders that are more permeable to human migration is based in part on the common Pacific predicament of poor resource endowments, rapidly growing populations, depletion and degradation of existing resources, and threats posed by anthropogenic climate change. Coupled with this is a history of colonisation that has left some Pacific peoples with liberal access to economic opportunities in developed states by virtue of their citizenship or preferential visa status, while others have no such opportunities. Both New Zealand and the Unite...
Pacific Lamprey Research and Restoration : Annual Report 1997.
The once abundant stocks of Pacific lamprey (Lampetra tridentata) above Bonneville Dam are currently depressed (Close et al. 1995). It is likely that many of the same factors that led to the decline of wild stocks of Columbia River Pacific salmon and steelhead have impacted Pacific lamprey populations as well. The Pacific Lamprey Research and Restoration Project, funded by Bonneville Power Administration, is a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation, the Columbia River Inter-Tribal Fish Commission, and Oregon State University with the goal to increase Pacific lamprey stocks above Bonneville Dam.
Pacific Lamprey Research and Restoration : Annual Report 1997.
1998-08-05
The once abundant stocks of Pacific lamprey (Lampetra tridentata) above Bonneville Dam are currently depressed (Close et al. 1995). It is likely that many of the same factors that led to the decline of wild stocks of Columbia River Pacific salmon and steelhead have impacted Pacific lamprey populations as well. The Pacific Lamprey Research and Restoration Project, funded by Bonneville Power Administration, is a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation, the Columbia River Inter-Tribal Fish Commission, and Oregon State University with the goal to increase Pacific lamprey stocks above Bonneville Dam.
Magnesium/calcium related neurological disorders in the ALS focus of the Kii Peninsula
1997-01-01
Current epidemiological surveys in the Western Pacific area and Kii Peninsula have suggested that low calcium(Ca), magnesium(Mg) and high aluminum(Al) and manganese(Mn) in river, soil and drinking water may be implicated in the pathogenetic process of amyotrophic lateral sclerosis(ALS) and Parkinsonism-dementia(PD). The condition of unbalanced minerals was experimentally mimicked in this study using rats. Male Wistar rats, weighing 200 g, were maintained for 90 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca-Mg diet, (D) low Ca-Mg diet with high Al. In the groups maintained on unbalanced mineral diets, Ca and Mg contents of the bones were lower than standard diet. On the other hand, Ca content of CNS showed higher values in the unbalanced diet groups than those in the standard diet group. This was determined by neutron activation analysis(NAA) at KUR. Also, Ca content in soft tissues of rats given unbalanced mineral diets was higher than those on standard diet. Mg content of soft tissues and spinal cord of rats was markedly lower in the low Ca-Mg plus high Al diet group than the other three groups as determined by inductively coupled plasma emission spectrometry(ICP). Six Kii cases with amyotrophic lateral sclerosis(ALS) also showed higher Ca and lower Mg contents in the CNS tissues than those of neurologically normal controls. The calcification of the spinal ligaments(CSL) has been reported in only 120 cases in the world and 28 cases of CSL in the Kii Peninsula have been found in the same foci as ALS. We analyzed Mg content of 7 spinal bones and 10 ligaments of the CSL and Ca content of 5 spinal bones compared with controls. The CSL showed lower values of Mg contents in bones and ligaments compared to controls. The Ca content in bones of CSL was significantly lower than that of controls. This suggests that the environmental factor may contribute to the pathogenesis of CSL due to low Ca and Mg intake as well as for ALS. (J.P.N.)
2007-06-01
Surf scoters are part of a community of sea ducks on the western coast of North America that have shown signs of long-term, unexplained declines in breeding bird numbers. Substantial numbers of scoters winter in the major harbours on the west coast, after breeding in the west-central northern boreal forest. To address the potential for contaminants to impact the health and survival of those birds, we investigated the condition and contamination of surf scoters during the winters of 1998-2001 at four foraging locations in the Strait of Georgia region of the Pacific coast of Canada. Vitamin A status was evaluated in liver and plasma samples collected from adults and juveniles, as part of a larger assessment of tissue contamination, body condition and biomarker responses. Individuals collected from a relatively contaminated site, Howe Sound, showed consistently low hepatic concentrations of retinol and retinyl palmitate forms of vitamin A, and gender-specific associations of retinyl palmitate with hepatic EROD activity. The relationship of hepatic retinol to retinyl palmitate was not constant across geographic locations, and a clear, linear relationship between the two forms of vitamin A was only evident in birds from the relatively uncontaminated site. This study also identified strong positive relationships between vitamin A and tissue burdens of cadmium and zinc. The positive association between hepatic retinyl palmitate and renal cadmium is similar to one observed in laboratory rats, in which a mechanism of interference with the controlled release of retinol from the liver was suggested.
Research into the deep waters of the eastern North Pacific. Final report
The deep physical and chemical regimen of the eastern North Pacific was investigated through deep hydrographic casts and the biomass of bathypelagic organisms studied through midwater traveling. (ACR)
Freshwater supplies threatened in central Pacific
2007-08-15
An international team from the Australian National University, Ecowise Environmental, the government of the Republic of Kiribati, the French agency CIRAD and the Pacific Islands Applied Geoscience Commission has been ...
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