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Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

Description: The coexistence of Dipodomys ordii and Perognathus hispidus with Peromyscus maniculatus and Reithrodontomys montanus was studied in a grassland association of central Texas. The food habits of these species were compared with information from habitat vegetation analysis in an effort to determine food selectivity and the amount and importance of niche overlap and competition among these rodents.
Date: May 1972
Creator: Alcoze, Thomas M.
Partner: UNT Libraries

[Rat trap]

Description: Photograph of a homemade rat trap. There are a series of sticks holding up a large board with large rocks resting on top.
Date: 195u
Creator: Clark, Joe
Partner: UNT Libraries Special Collections

Some Common Mammals of Western Montana in Relation to Agriculture and Spotted Fever

Description: "Since it is known that spotted fever is communicated from wild animals to human beings by the bite of infected wood ticks and that the two younger stages live almost entirely on small native rodents -- from which they occasionally contract the infection -- it is evident that these tick hosts should be destroyed, at least around ranches. The extensive damage done by the same animals to agricultural interests is another important reason for their destruction. The chief purpose of this publication is to point out the best methods of destroying these native animals." -- p. 6. Among the rodents discussed in the bulletin are squirrels, chipmunks, woodchucks, mice, rats, gophers, rabbits, badgers, and weasels.
Date: 1912
Creator: Birdseye, Clarence, 1886-1956
Partner: UNT Libraries Government Documents Department

Pocket-gopher control.

Description: Describes the characteristics of the pocket gopher, the damage it can cause to farm crops, and methods of control.
Date: 1941
Creator: Crouch, W. E. (Winney Elmer), 1891-
Partner: UNT Libraries Government Documents Department

Characterization of evolutionary rates and constraints in three mammalian genomes

Description: We present an analysis of rates and patterns of microevolutionary phenomena that have shaped the human, mouse, and rat genomes since their last common ancestor. We find evidence for a shift in the mutational spectrum between the mouse and rat lineages, with the net effect being a relative increase in GC content in the rat genome. Our estimate for the neutral point substitution rate separating the two rodents is 0.196 substitutions per site, and 0.65 substitutions per site for the tree relating all three mammals. Small insertions and deletions of 1-10 bp in length (''microindels'') occur at approximately 5 percent of the point substitution rate. Inferred regional correlations in evolutionary rates between lineages and between types of sites support the idea that rates of evolution are influenced by local genomic or cell biological context. No substantial correlations between rates of point substitutions and rates of microindels are found, however, implying that the influences that affect these processes are distinct. Finally, we have identified those regions in the human genome that are evolving slowly, which are likely to include functional elements important to human biology. At least 5 percent of the human genome is under substantial constraint, most of which is noncoding.
Date: February 15, 2004
Creator: Cooper, Gregory M.; Brudno, Michael; Stone, Eric A.; Dubchak, Inna; Batzoglou, Serafim & Sidow, Arend
Partner: UNT Libraries Government Documents Department

The Association between Hantavirus Infection and Selenium Deficiency in Mainland China

Description: This article studies the role of selenium concentration in hemorrhagic fever with renal syndrome (HFRS) caused by hantaviruses, using a multidisciplinary approach combining ecological analysis with preliminary experimental data.
Date: January 20, 2015
Creator: Fang, Liqun; Goeijenbier, Marco; Zuo, Shu-Qing; Wang, Li-Ping; Liang, Song; Klein, Sabra L. et al.
Partner: UNT College of Arts and Sciences

The Influence of a Return of Native Grasslands upon the Ecology and Distribution of Small Rodents in Big Bend National Park

Description: In the southwestern United States there is a delicate balance between the existing grasslands and the rodent fauna. The purpose of this investigation was to determine the influence of secondary succession of native grasslands upon the ecology and distribution of small rodents. Two methods of determining the rodent species were plot quadrates and trap lines using Sherman live traps.
Date: August 1971
Creator: Baccus, John T.
Partner: UNT Libraries

Mitochondrial DNA Restriction Site Analysis of the Phylogeny of the Truei and Boylii Species Groups of the Rodent Genus Peromyscus (Cricetidae)

Description: The phylogenetics of eight species of the Peromyscus truei and P. boylii species groups from 15 populations were analyzed based on mitochondrial DNA sequence differentiation, using 13 hexanucleotide specific restriction enzymes. P. difficilis, P. nasutus, and P. attwateri were found to be members of the same clade. P. leucopus was not found to be closely related to any of the species of the boylii or truei species groups. Phylogenetic interpretations for the remaining species differed based on Wagner and Dollo parsimony analyses. P. true appears to be most closely related to P. gratus based on Wagner parsimony and the phenetic analysis, while the relationship of P. gratus to other species could not be resolved based on Dollo parsimony.
Date: August 1991
Creator: DeWalt, Theresa Spradling
Partner: UNT Libraries

Rat control.

Description: Discusses the damage that rats can cause, and provides methods for effective exclusion and destruction of the pest.
Date: 1928
Creator: Silver, James, b. 1890.
Partner: UNT Libraries Government Documents Department

Small mammal study of Sandia Canyon, 1994 and 1995

Description: A wide range of plant and wildlife species utilize water discharged from facilities at Los Alamos National Laboratory (LANL). The purpose of this study was to gather baseline data of small mammal populations and compare small mammal characteristics within three areas of Sandia Canyon, which receives outfall effluents from multiple sources. Three small mammal trapping webs were placed in the upper portion of Sandia Canyon, the first two were centered in a cattail-dominated marsh with a ponderosa pine overstory and the third web was placed in a much drier transition area with a ponderosa pine overstory. Webs 1 and 2 had the highest species diversity indices with deer mice the most commonly captured species in all webs. However, at Web 1, voles, shrews, and harvest mice, species more commonly found in moist habitats, made up a much greater overall percentage (65.6%) than did deer mice and brush mice (34.5%). The highest densities and biomass of animals were found in Web 1 with a continual decrease in density estimates in each web downstream. There is no statistical difference between the mean body weights of deer mice and brush mice between sites. Mean body length was also determined not to be statistically different between the webs (GLM [deer mouse], F = 0.89, p = 0.4117; GLM [brush mouse], F = 2.49, p = 0.0999). Furthermore, no statistical difference between webs was found for the mean lean body masses of deer and brush mice (GLM [deer mouse], F = 2.54, p = 0.0838; GLM [brush mouse], F = 1.60, p = 0.2229). Additional monitoring studies should be conducted in Sandia Canyon so comparisons over time can be made. In addition, rodent tissues should be sampled for contaminants and then compared to background or control populations elsewhere at the Laboratory or at an off-site ...
Date: November 1, 1996
Creator: Bennett, K. & Biggs, J.
Partner: UNT Libraries Government Documents Department

Evaluation of Ethanol’s Effects on the Biophysical Characteristics of Licking

Description: Alcohol use disorders are a public health issue related to adverse effects for individuals and society. A low level of response, or decreased sensitivity, to alcohol has been identified as a heritable risk factor for development of alcohol use disorders. One method for researching level of response to alcohol is through the use of rodent models, which are developed to mimic human conditions while eliminating barriers to conducting research with people. Current rodent models used to evaluate effects of ethanol on motor performance have been criticized for not being well matched to human tasks that measure level of change in body sway after alcohol consumption. This study looks at oromotor behavior as a potential alternative to gross motor performance in hopes of increasing correspondence between human and rodent measures of intoxication. To evaluate rodent oromotor performance a force transducer lickometer is used to measure several dimensions of licking behavior after administration of different concentrations of ethanol solution via gavage. Results show that force of licking is not sensitive to dose of ethanol. The total number of licks per session show dose related decreases and licking rhythm, evaluated by the length and distribution of interlick intervals, either increased or decreased for three of the four subjects. Recommendations are made for procedural modifications in order to reduce variability in data and further investigate oromotor performance and level of response to alcohol.
Date: December 2014
Creator: Stewart, Daryl Ellen
Partner: UNT Libraries

Harmful and Beneficial Mammals of the Arid Interior, With Special Reference to the Carson and Humboldt Valleys, Nevada

Description: "Large tracts of arid desert are now being reclaimed and converted into arable land, rich in agricultural possibilities. Crops, trees, live stock, poultry, and ditch banks in this reclaimed territory suffer from the depredations of certain mammals, and the farmers, many of whom are from remote localities, are not always able to discriminate between friends and foes; nor are they always acquainted with cheap and effective methods of destroying the noxious kinds. The report comprises a brief account of the commoner mammals of the region, with special reference to their economic status and the best means of destroying the noxious species, and has been prepared as a practical aid to the ranchmen of the arid interior." -- p. 2. Among the animal discussed are squirrels, chipmunks, various types of mice, muskrats, rats, gophers, rabbits, bobcats, desert foxes, coyotes, skunks, badgers, weasels, minks, otters, and bats.
Date: 1908
Creator: Bailey, Vernon, 1864-1942
Partner: UNT Libraries Government Documents Department

How to Get Rid of Rats.

Description: Describes methods of eliminating a rat infestation in terms of food sources, poisons, trapping, and rat proofing. Also describes the natural enemies and diseases of rats, and the benefits of community cooperation in their control.
Date: April 1923
Creator: Silver, James, b. 1890
Partner: UNT Libraries Government Documents Department

Relative susceptibilities of male germ cells to genetic defects induced by cancer chemotherapies

Description: Some chemotherapy regimens include agents that are mutagenic or clastogenic in model systems. This raises concerns that cancer survivors, who were treated before or during their reproductive years, may be at increased risks for abnormal reproductive outcomes. However, the available data from offspring of cancer survivors are limited, representing diverse cancers, therapies, time-to-pregnancies, and reproductive outcomes. Rodent breeding data after paternal exposures to individual chemotherapeutic agents illustrate the complexity of factors that influence the risk for transmitted genetic damage including agent, dose, endpoint, and the germ-cell susceptibility profiles that vary across agents. Direct measurements of chromosomal abnormalities in sperm of mice and humans by sperm FISH have corroborated the differences in germ-cell susceptibilities. The available evidence suggests that the risk of producing chromosomally defective sperm is highest during the first few weeks after the end of chemotherapy, and decays with time. Thus, sperm samples provided immediately after the initiation of cancer therapies may contain treatment-induced genetic defects that will jeopardize the genetic health of offspring.
Date: June 15, 2004
Creator: Wyrobek, A J; Schmid, T E & Marchetti, F
Partner: UNT Libraries Government Documents Department

Mechanisms and chemical induction of aneuploidy in rodent germ cells

Description: The objective of this review is to suggest that the advances being made in our understanding of the molecular events surrounding chromosome segregation in non-mammalian and somatic cell models be considered when designing experiments for studying aneuploidy in mammalian germ cells. Accurate chromosome segregation requires the temporal control and unique interactions among a vast array of proteins and cellular organelles. Abnormal function and temporal disarray among these, and others to be inidentified, biochemical reactions and cellular organelles have the potential for predisposing cells to aneuploidy. Although numerous studies have demonstrated that certain chemicals (mainly those that alter microtubule function) can induce aneuploidy in mammalian germ cells, it seems relevant to point out that such data can be influenced by gender, meiotic stage, and time of cell-fixation post-treatment. Additionally, a consensus has not been reached regarding which of several germ cell aneuploidy assays most accurately reflects the human condition. More recent studies have shown that certain kinase, phosphatase, proteasome, and topoisomerase inhibitors can also induce aneuploidy in rodent germ cells. We suggest that molecular approaches be prudently incorporated into mammalian germ cell aneuploidy research in order to eventually understand the causes and mechanisms of human aneuploidy. Such an enormous undertaking would benefit from collaboration among scientists representing several disciplines.
Date: October 15, 2004
Creator: Mailhes, J B & Marchetti, F
Partner: UNT Libraries Government Documents Department

Homologous recombination contributes to the repair of DNA double-strand breaks induced by high-energy iron ions

Description: To test the contribution of homologous recombinational repair (HRR) in repairing DNA damaged sites induced by high-energy iron ions, we used: (1) HRR-deficient rodent cells carrying a deletion in the RAD51D gene and (2) syngeneic human cells impaired for HRR by RAD51D or RAD51 knockdown using RNA interference. We show that in response to iron ions, HRR contributes to cell survival in rodent cells, and that HRR-deficiency abrogates RAD51 foci formation. Complementation of the HRR defect by human RAD51D rescues both enhanced cytotoxicity and RAD51 foci formation. For human cells irradiated with iron ions, cell survival is decreased, and, in p53 mutant cells, the levels of mutagenesis are increased when HRR is impaired. Human cells synchronized in S phase exhibit more pronounced resistance to iron ions as compared with cells in G1 phase, and this increase in radioresistance is diminished by RAD51 knockdown. These results implicate a role for RAD51-mediated DNA repair (i.e. HRR) in removing a fraction of clustered lesions induced by charged particle irradiation. Our results are the first to directly show the requirement for an intact HRR pathway in human cells in ensuring DNA repair and cell survival in response to high-energy high LET radiation.
Date: June 29, 2010
Creator: Zafar, Faria; Seidler, Sara B.; Kronenberg, Amy; Schild, David & Wiese, Claudia
Partner: UNT Libraries Government Documents Department

Improved mutagen-testing systems in mice. Progress report, 1 September 1978-30 October 1979

Description: The purpose of this project is to produce improved mutagen-testing systems in mice. Our approach is to produce chromosomal inversion systems and to improve the techniques necessary to induce, detect, genetically define, and combine inversions in effective useful mutation-test systems. Another specific objective has been to test the systems produced with respect to their effectiveness. Another objective has been to mark, maintain, and study recessive detrimentals and lethals induced in the validation-testing of these systems. Of particular importance is to study induced recessives for dominant effects on fitness. A final broad objective has been to use the induced inversions and recessive lethals for studies of basic problems in mammalian genetics, growth, and development.
Date: November 1, 1979
Creator: Roderick, T.H.
Partner: UNT Libraries Government Documents Department

Hantavirus testing in rodents of north-central New Mexico 1993-1995

Description: In 1993, an outbreak of a new strain of hantavirus in the southwestern US indicated that deer mice (Peromyscus maniculatus) was the primary carrier of the virus. In 1993, 1994, and 1995 the Ecological Studies Team (EST) at Los Alamos National Laboratory surveyed small mammal populations using live capture-recapture methods in Los Alamos County, New Mexico, to determine seroprevalence of hantavirus in this region. EST used trapping grids in 1993 and 1994 and used trapping webs in 1995. Grids were 120 m x 120 m (400 ft x 400 ft) with 144 trap stations at each grid. Three webs consisting of 148 traps each were used in 1995. Trapping took place over 4 to 8 consecutive nights. Programs CAPTURE and Distance were used to determine density estimates for grids and webs, respectively. Blood samples were analyzed in 1993 by the Centers for Disease Control and the University of New Mexico, School of Medicine. The 1994 and 1995 samples were analyzed by the University of New Mexico, School of Medicine. The deer mouse (Peromyscus maniculatus) was the most commonly captured species at all locations except one site where voles (Microtus spp.) were the most commonly captured species. Other species sampled included: harvest mice (Reithrodontomys megalotis), woodrats (Neotoma spp.), shrews (Sorex spp.), white-footed mice (Peromyscus leucopus), pinyon mice (Peromyscus trueii), and brush mouse (Peromyscus boylii). Results of the 1993, 1994, and 1995 testing identified a total overall seroprevalence rate among deer mice of approximately 5.5%, 4.2%, and 0%, respectively. Several other species tested positive for the hantavirus but it is uncertain if it is Sin Nombre virus. Further studies will be necessary to quantify seroprevalence rates in those species. Higher seroprevalence rates were found in males than females. Seroprevalence rates for Los Alamos County were much lower than elsewhere in the region.
Date: March 1, 1996
Creator: Biggs, J.; Bennett, K. & Salisbury, M.
Partner: UNT Libraries Government Documents Department

Clinical anatomy of the European hamster, Cricetus cricetus, L.

Description: This handbook outlines the external and internal anatomy of the European hamster, including "clinically relevant systems such as the respiratory system" (p. iii). It also includes a diagram of the normal distribution of hamsters throughout Germany. The index begins on page 211.
Date: 1978
Creator: Reznik, Gerd.; Schuller, Hildegard M. & Mohr, U. (Ulrich)
Partner: UNT Libraries Government Documents Department

[News Script: Better mousetrap]

Description: Script from the WBAP-TV station in Fort Worth, Texas, covering a news story about W. A. Uttz inventing a device making it easier to load mousetraps.
Date: September 20, 1951
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Effect of Woody Debris abundance on daytime refuge use by cotton mice.

Description: Abstract - Daytime refuges are important to nocturnal rodents for protection from predators and environmental extremes. Because refuges of forest-dwelling rodents are often associated with woody debris, we examined refuge use by 37 radio-collared Peromyscus gossypinus (cotton mice) in experimental plots with different levels of woody debris. Treatment plots had six times (≈ 60 m3/ha) the volume of woody debris as control plots (≈ 10 m3/ha). Of 247 refuges, 159 were in rotting stumps (64%), 32 were in root boles (13%), 19 were in brush piles (8%), and 16 were in logs (6%); 10 refuges could not be identified. Stumps were the most common refuge type in both treatments, but the distribution of refuge types was significantly different between treatment and control plots. Root boles and brush piles were used more on treatment plots than on control plots, and logs were used more on control plots than on treatment plots. Refuge type and vegetation cover were the best predictors of refuge use by cotton mice; root bole refuges and refuges with less vegetation cover received greater-than-expected use by mice. Abundant refuges, particularly root boles, may improve habitat quality for cotton mice in southeastern pine forests.
Date: July 1, 2007
Creator: Hinkelman, Travis, M. & Loeb, Susan, C.
Partner: UNT Libraries Government Documents Department

RADIATION ECOLOGY ISSUES ASSOCIATED WITH MURINE RODENTS AND SHREWS IN THE CHERNOBYL EXCLUSION ZONE

Description: This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals, and reviews interspecies differences in radionuclide accumulations and factors affecting the radionuclide accumulations. It is shown that bioavailability of radionuclides in the 'soil-to-plant' chain and a trophic specialization of animals play key roles in determining their actual contamination levels. The total absorbed dose rates in small mammals significantly reduced during the years following the Chernobyl Nuclear Power Plant accident. In 1986, the absorbed dose rate reached 1.3-6.0 Gy hr{sup -1} in the central areas of the Chernobyl Exclusion Zone (the 'Red Forest'). In 1988 and 1990, the total absorbed dose rates were 1.3 and 0.42 Gy hr{sup -1}, respectively. In 1995, 2000, and 2005, according to the present study, the total absorbed dose rates rarely exceeded 0.00023, 0.00018, and 0.00015 Gy hr{sup -1}, respectively. Contributions of individual radiation sources into the total absorbed dose are described.
Date: October 1, 2011
Creator: Farfan, E. & Jannik, T.
Partner: UNT Libraries Government Documents Department

Mode-of-Action Uncertainty for Dual-Mode Carcinogens:Lower Bounds for Naphthalene-Induced Nasal Tumors in Rats Implied byPBPK and 2-Stage Stochastic Cancer Risk Models

Description: As reflected in the 2005 USEPA Guidelines for Cancer Risk Assessment, some chemical carcinogens may have a site-specific mode of action (MOA) that is dual, involving mutation in addition to cell-killing induced hyperplasia. Although genotoxicity may contribute to increased risk at all doses, the Guidelines imply that for dual MOA (DMOA) carcinogens, judgment be used to compare and assess results obtained using separate ''linear'' (genotoxic) vs. ''nonlinear'' (nongenotoxic) approaches to low-level risk extrapolation. However, the Guidelines allow the latter approach to be used only when evidence is sufficient to parameterize a biologically based model that reliably extrapolates risk to low levels of concern. The Guidelines thus effectively prevent MOA uncertainty from being characterized and addressed when data are insufficient to parameterize such a model, but otherwise clearly support a DMOA. A bounding factor approach--similar to that used in reference dose procedures for classic toxicity endpoints--can address MOA uncertainty in a way that avoids explicit modeling of low-dose risk as a function of administered or internal dose. Even when a ''nonlinear'' toxicokinetic model cannot be fully validated, implications of DMOA uncertainty on low-dose risk may be bounded with reasonable confidence when target tumor types happen to be extremely rare. This concept was illustrated for the rodent carcinogen naphthalene. Bioassay data, supplemental toxicokinetic data, and related physiologically based pharmacokinetic and 2-stage stochastic carcinogenesis modeling results all clearly indicate that naphthalene is a DMOA carcinogen. Plausibility bounds on rat-tumor-type specific DMOA-related uncertainty were obtained using a 2-stage model adapted to reflect the empirical link between genotoxic and cytotoxic effects of the most potent identified genotoxic naphthalene metabolites, 1,2- and 1,4-naphthoquinone. Resulting bounds each provided the basis for a corresponding ''uncertainty'' factor <1 appropriate to apply to estimates of naphthalene risk obtained by linear extrapolation under a default genotoxic MOA assumption. This procedure is ...
Date: January 30, 2007
Creator: Bogen, K T
Partner: UNT Libraries Government Documents Department