| interspecific comparison of hantavirus prevalence in peromyscus populations from a fragmented agro-ecosystem in indiana, usa. | comparatively little is known about hantavirus prevalence within rodent populations from the midwestern us, where two species of native mice, the prairie deer mouse ( peromyscus maniculatus bairdii) and the white-footed mouse ( peromyscus leucopus noveboracensis), are dominant members of rodent communities. we sampled both species in central indiana and tested individuals for presence of hantavirus antibodies to determine whether seroprevalence (percent of individuals with antibodies reactive to ... | 2018 | 28977768 |
| evaluating the impacts of coinfection on immune system function of the deer mouse ( peromyscus maniculatus) using sin nombre virus and bartonella as model pathogen systems. | : simultaneous infections with multiple pathogens can alter the function of the host's immune system, often resulting in additive or synergistic morbidity. we examined how coinfection with the common pathogens sin nombre virus (snv) and bartonella sp. affected aspects of the adaptive and innate immune responses of wild deer mice ( peromyscus maniculatus). adaptive immunity was assessed by measuring snv antibody production; innate immunity was determined by measuring levels of c-reactive protein ... | 2018 | 28977767 |
| isotopic niche variation from the holocene to today reveals minimal partitioning and individualistic dynamics among four sympatric desert mice. | species interact with each other and their environment over a range of temporal scales, yet our understanding of resource partitioning and the mechanisms of species coexistence is largely restricted to modern time-scales of years to decades. furthermore, the relative magnitudes of inter- vs. intraspecific variation in resource use are rarely considered, despite the potential for the latter to influence a species' ability to cope with changing environmental conditions. modern desert rodent commun ... | 2018 | 29048750 |
| is species richness driving intra- and interspecific interactions and temporal activity overlap of a hantavirus host? an experimental test. | high species diversity of the potential animal host community for a zoonotic pathogen may reduce pathogen transmission among the most competent host, a phenomenon called the "dilution effect", but the mechanisms driving this effect have been little studied. one proposed mechanism is "encounter reduction" where host species of low-competency decrease contact rates between infected and susceptible competent hosts, especially in directly transmitted diseases. we conducted an experiment in outdoor e ... | 2017 | 29141047 |
| insights on the host associations and geographic distribution of hymenolepis folkertsi (cestoda: hymenolepididae) among rodents across temperate latitudes of north america. | synoptic data and an understanding of helminth parasite diversity among diverse rodent assemblages across temperate latitudes of north america remain remarkably incomplete. renewed attention to comprehensive survey and inventory to establish the structure of biodiverse faunas is essential in providing indicators and proxies for identifying the outcomes of accelerating change linked to climate warming and anthropogenic forcing. subsequent to the description of hymenolepis folkertsi in the oldfiel ... | 2016 | 27630100 |
| brachylaime microti: a mechanistic simulation model of the parasite, its intermediate snail host, oreohelix strigosa, and its definitive rodent hosts, peromyscus maniculatus and microtus montanus. | | 1977 | 320029 |
| buffering and plasticity in vital rates of oldfield rodents. | 1. under the hypothesis of environmental buffering, populations are expected to minimize the variance of the most influential vital rates; however, this may not be a universal principle. species with a life span <1 year may be less likely to exhibit buffering because of temporal or seasonal variability in vital rate sensitivities. further, plasticity in vital rates may be adaptive for species in a variable environment with reliable cues. 2. we tested for environmental buffering and plasticity in ... | 2012 | 22375923 |
| winter adaptations of male deer mice (peromyscus maniculatus) and prairie voles (microtus ochrogaster) that vary in reproductive responsiveness to photoperiod. | individuals of many nontropical rodent species restrict breeding to the spring and summer. seasonal reproductive quiescence putatively reflects the energetic incompatibility of breeding and thermoregulatory activities. however, so-called "out-of-season" breeding occurs in virtually all rodent populations examined, suggesting that the incompatibility can be resolved. both reproductive inhibition and development of energy-saving adaptations are mediated by environmental photoperiod, but some indiv ... | 1993 | 8280911 |
| small mammals as sentinels of oil sands related contaminants and health effects in northeastern alberta, canada. | the extraction of bitumen in areas of northeastern alberta (canada) has been associated with the release of complex mixtures of metals, metalloids, and polycyclic aromatic compounds (pacs) to the environment. to mitigate effects on ecosystems, canadian legislation mandates that disturbed areas be reclaimed to an ecologically sustainable state after active operations. however, as part of reclamation activities, exposure to, and effects on wildlife living in these areas is not generally assessed. ... | 2016 | 26555251 |
| characterization of a male reproductive transcriptome for peromyscus eremicus (cactus mouse). | rodents of the genus peromyscus have become increasingly utilized models for investigations into adaptive biology. this genus is particularly powerful for research linking genetics with adaptive physiology or behaviors, and recent research has capitalized on the unique opportunities afforded by the ecological diversity of these rodents. well characterized genomic and transcriptomic data is intrinsic to explorations of the genetic architecture responsible for ecological adaptations. therefore, th ... | 2016 | 27812417 |
| embryonic development of the deer mouse, peromyscus maniculatus. | deer mice, or peromyscus maniculatus, are an emerging model system for use in biomedicine. p. maniculatus are similar in appearance to laboratory mice, mus musculus, but are more closely related to hamsters than to mus. the laboratory strains of peromyscus have captured a high degree of the genetic variability observed in wild populations, and are more similar to the genetic variability observed in humans than are laboratory strains of mus. the peromyscus genetic stock center at the university o ... | 2016 | 26930071 |
| emergence and evolution of zfp36l3. | in most mammals, the zfp36 gene family consists of three conserved members, with a fourth member, zfp36l3, present only in rodents. the zfp36 proteins regulate post-transcriptional gene expression at the level of mrna stability in organisms from humans to yeasts, and appear to be expressed in all major groups of eukaryotes. in mus musculus, zfp36l3 expression is limited to the placenta and yolk sac, and is important for overall fecundity. we sequenced the zfp36l3 gene from more than 20 represent ... | 2016 | 26493225 |
| chemical and behavioral ecology of foraging in prairie rattlesnakes (crotalus viridis viridis). | free-ranging prairie rattlesnakes (crotalus viridis viridis) exhibit lengthy vernal migrations upon emergence from winter hibernation. a series of laboratory experiments was designed to test hypotheses regarding the function and causation of vernal movements. rattlesnakes obtained from wyoming and colorado populations were used. first, we hypothesized that the function of vernal movements is to locate small mammal prey. second, we predicted that activec. v. viridis use prey chemicals, as well as ... | 1990 | 24264898 |
| intraspecific functional diversity of common species enhances community stability. | common species are fundamental to the structure and function of their communities and may enhance community stability through intraspecific functional diversity (ifd). we measured among-habitat and within-habitat ifd (i.e., among- and within-plant community types) of two common small mammal species using stable isotopes and functional trait dendrograms, determined whether ifd was related to short-term population stability and small mammal community stability, and tested whether spatially explici ... | 2017 | 28261464 |
| effects of extra food on peromyscus and clethrionomys populations in the southern yukon. | if food supply limits density in rodent populations, the addition of supplemental food ought to increase population size. from may to september we added food on 2-hectare areas of white spruce forest in the southern yukon. in 1977, we used oats with no measurable impact. in 1978 and 1979 we used sunflower seeds and doubled or tripled the population densities of peromyscus maniculatus and clethrionomys rutilus. supplemental feeding with sunflower seeds increased juvenile production in both specie ... | 1981 | 28310015 |
| molecular epidemiology of bartonella species isolated from ground squirrels and other rodents in northern california. | bartonella spp. are endemic in wild rodents in many parts of the world. a study conducted in two northern california counties (sonoma and yolo) sampling california ground squirrels (otospermophilus beecheyi) and four other rodent species (peromyscus maniculatus, p. boylii, p. truei and neotoma fuscipes) led to the isolation of small gram-negative bacilli which were identified as bartonella spp. based on colony morphology, polymerase chain reaction-restriction fragment length polymorphism (pcr-rf ... | 2016 | 27245290 |
| element content in tissues of four rodent species sampled in the geysers geothermal steamfield. | liver and kidney tissue samples from four rodent species collected in the geysers geothermal steamfield of northern california were analyzed for content of 28 elements. element concentrations in samples from the developed region of the geysers were compared with samples from undeveloped reference regions to determine the influence of geothermal power development on element content in small mammal tissues. eight elements (b, ca, cu, mg, mn, p, sr, ti) were enriched in samples from the geysers, 12 ... | 1989 | 15092429 |
| detection of coccidioidal antibodies in serum of a small rodent community in baja california, mexico. | coccidioidomycosis (valley fever) represents a serious threat to inhabitants of endemic areas of north america. despite successful clinical isolations of the fungal etiological agent, coccidioides spp., the screening of environmental samples has had low effectiveness, mainly because of the poor characterization of coccidioides ecological niche. we explored valle de las palmas, baja california, mexico, a highly endemic area near the u.s.-mexico border, where we previously detected coccidioides vi ... | 2014 | 24607357 |
| mystr: an endogenous retrovirus family in mammals that is undergoing recent amplifications to unprecedented copy numbers. | a large percentage of the repetitive elements in mammalian genomes are retroelements, which have been moved primarily by line-1 retrotransposons and endogenous retroviruses. although line-1 elements have remained active throughout the mammalian radiation, specific groups of endogenous retroviruses generally remain active for comparatively shorter periods of time. identification of an unusual extinction of line-1 activity in a group of south american rodents has opened a window for examination of ... | 2005 | 16282470 |
| peromyscus as a model system for understanding the regulation of maternal behavior. | the genus peromyscus has been used as a model system for understanding maternal behavior because of the diversity of reproductive strategies within this genus. this review will describe the ecological factors that determine litter size and litter quality in polygynous species such as peromyscus leucopus and peromyscus maniculatus. we will also outline the physiological and social factors regulating maternal care in peromyscus californicus, a monogamous and biparental species. because biparental ... | 2017 | 27381343 |
| effects of developmental bisphenol a exposure on reproductive-related behaviors in california mice (peromyscus californicus): a monogamous animal model. | bisphenol a (bpa), a pervasive, endocrine disrupting compound (edc), acts as a mixed agonist-antagonist with respect to estrogens and other steroid hormones. we hypothesized that sexually selected traits would be particularly sensitive to edc. consistent with this concept, developmental exposure of males from the polygynous deer mouse, peromyscus maniculatus, to bpa resulted in compromised spatial navigational ability and exploratory behaviors, while there was little effect on females. here, we ... | 2013 | 23405200 |
| sex differences in immunocompetence differ between two peromyscus species. | males generally exhibit reduced immunocompetence and greater susceptibility to disease than females. the explanations for why males may be more susceptible to disease than females fall into two categories: 1) the proximate mechanisms mediating immunity, such as hormonal mechanisms, and 2) variation in reproductive success between the sexes. the present study examined the extent to which these factors contribute to sex differences in cell-mediated immune function in polygynous peromyscus manicula ... | 1997 | 9277551 |
| the comparative distribution of forebrain receptors for neurohypophyseal peptides in monogamous and polygamous mice. | several recent studies have suggested that the neurohypophyseal peptide oxytocin may have a role within the brain to mediate various forms of affiliative behavior. as the regulation of oxytocin function may be largely determined by the number and distribution of its membrane bound receptor, we investigated oxytocin receptor distribution in two peromyscus species selected for differences in affiliative behavior. using in vitro receptor autoradiography with the selective oxytocin receptor ligand [ ... | 1991 | 1656322 |
| admixture on the northern front: population genomics of range expansion in the white-footed mouse (peromyscus leucopus) and secondary contact with the deer mouse (peromyscus maniculatus). | range expansion has genetic consequences expected to result in differentiated wave-front populations with low genetic variation and potentially introgression from a local species. the northern expansion of peromyscus leucopus in southern quebec provides an opportunity to test these predictions using population genomic tools. our results show evidence of recent and post-glacial expansion. genome-wide variation in p. leucopus indicates two post-glacial lineages are separated by the st. lawrence ri ... | 2017 | 28902189 |
| control of breathing and ventilatory acclimatization to hypoxia in deer mice native to high altitudes. | we compared the control of breathing and heart rate by hypoxia between high- and low-altitude populations of peromyscus mice, to help elucidate the physiological specializations that help high-altitude natives cope with o2 limitation. | 2017 | 28640969 |
| microsatellite markers reveal low frequency of natural hybridization between the white-footed mouse (peromyscus leucopus) and deer mouse (peromyscus maniculatus) in southern quebec, canada. | in some parts of southern quebec, two closely related rodent species - the white-footed mouse (peromyscus leucopus) and the deer mouse (peromyscus maniculatus) - have recently come in contact because of climate-driven changes in the distribution of the former. both species share similar morphology, ecology, and life history traits, which suggests that natural hybridization may be possible. hybridization among these two species can have important implications on the ecological roles these rodents ... | 2017 | 28177836 |
| regulatory changes contribute to the adaptive enhancement of thermogenic capacity in high-altitude deer mice. | in response to hypoxic stress, many animals compensate for a reduced cellular o(2) supply by suppressing total metabolism, thereby reducing o(2) demand. for small endotherms that are native to high-altitude environments, this is not always a viable strategy, as the capacity for sustained aerobic thermogenesis is critical for survival during periods of prolonged cold stress. for example, survivorship studies of deer mice (peromyscus maniculatus) have demonstrated that thermogenic capacity is unde ... | 2012 | 22586089 |
| coexistence of white-footed mice and deer mice may be mediated by fluctuating environmental conditions. | white-footed mice, peromyscus leucopus noveboracensis, and deer mice, p. maniculatus nubiterrae, occur sympatically throughout much of the appalachian mountains of the eastern united states. previous studies have shown that these two species are behaviorally and ecologically similar and do not partition food or microhabitat. in this paper i use a 14-year data set to demonstrate that the two species have differential population growth and survival rates in response to food abundance and season, w ... | 1996 | 28307870 |
| linking songbird nest predation to seedling density: sugar maple masting as a resource pulse in a forest food web. | the ecological literature presents considerable evidence for top-down forcing on the maintenance of species diversity. yet, in temperate forests, bottom-up forces often exert a strong influence on ecosystem functioning. here, we report on the indirect influence of a pulsed resource, sugar maple (acer saccharum) seed production, on nest survival in a migratory songbird. we hypothesized that seed production in year t would determine daily nest survival rate in year t + 1 through its effects on see ... | 2017 | 29299253 |
| peromyscus maniculatus bairdii as a naturalistic mammalian model of obsessive-compulsive disorder: current status and future challenges. | obsessive-compulsive disorder (ocd) is a prevalent and debilitating condition, characterized by intrusive thoughts and repetitive behavior. animal models of ocd arguably have the potential to contribute to our understanding of the condition. deer mice (permomyscus maniculatus bairdii) are characterized by stereotypic behavior which is reminiscent of ocd symptomology, and which may serve as a naturalistic animal model of this disorder. moreover, a range of deer mouse repetitive behaviors may be r ... | 2017 | 29214602 |
| effects of hypoxia at different life stages on locomotory muscle phenotype in deer mice native to high altitudes. | animals native to high altitude must overcome the constraining effects of hypoxia on tissue o2 supply to support routine metabolism, thermoregulation in the cold, and exercise. deer mice (peromyscus maniculatus) native to high altitude have evolved an enhanced aerobic capacity in hypoxia, along with increased capillarity and oxidative capacity of locomotory muscle. here, we examined whether exposure to chronic hypoxia during development or adulthood affects muscle phenotype. deer mice from a hig ... | 2017 | 29175484 |
| fuel use in mammals: conserved patterns and evolved strategies for aerobic locomotion and thermogenesis. | effective aerobic locomotion depends on adequate delivery of oxygen and an appropriate allocation of metabolic substrates. the use of metabolic substrates during exercise follows a predictive pattern of lipid and carbohydrate oxidation that is similar in lowland native cursorial mammals. we have found that in two highland lineages of mice (phyllotis and peromyscus) the fuel use pattern is shifted to a greater reliance on carbohydrates compared to their lowland conspecifics and congenerics. howev ... | 2017 | 28859408 |
| circulatory mechanisms underlying adaptive increases in thermogenic capacity in high-altitude deer mice. | we examined the circulatory mechanisms underlying adaptive increases in thermogenic capacity in deer mice (peromyscus maniculatus) native to the cold hypoxic environment at high altitudes. deer mice from high- and low-altitude populations were born and raised in captivity to adulthood, and then acclimated to normoxia or hypobaric hypoxia (simulating hypoxia at ∼4300 m). thermogenic capacity [maximal o2 consumption (v̇o2,max), during cold exposure] was measured in hypoxia, along with arterial o2 ... | 2017 | 28839010 |
| the genetic basis of parental care evolution in monogamous mice. | parental care is essential for the survival of mammals, yet the mechanisms underlying its evolution remain largely unknown. here we show that two sister species of mice, peromyscus polionotus and peromyscus maniculatus, have large and heritable differences in parental behaviour. using quantitative genetics, we identify 12 genomic regions that affect parental care, 8 of which have sex-specific effects, suggesting that parental care can evolve independently in males and females. furthermore, some ... | 2017 | 28424518 |
| evolved changes in the intracellular distribution and physiology of muscle mitochondria in high-altitude native deer mice. | mitochondrial function changes over time at high altitudes, but the potential benefits of these changes for hypoxia resistance remains unclear. we used high-altitude-adapted populations of deer mice, which exhibit enhanced aerobic performance in hypoxia, to examine whether changes in mitochondrial physiology or intracellular distribution in the muscle contribute to hypoxia resistance. permeabilized muscle fibres from the gastrocnemius muscle had higher respiratory capacities in high-altitude mic ... | 2017 | 28418073 |
| quantitative shedding of multiple genotypes of cryptosporidium and giardia by deer mice ( peromyscus maniculatus ) in a major agricultural region on the california central coast. | deer mice ( peromyscus maniculatus ) are abundant and widely distributed rodents in north america that occupy diverse habitats, including agricultural landscapes. giardia and cryptosporidium are common parasites in wildlife including deer mice, which may play a role in on-farm contamination of produce. an important step in assessing the risk of produce contamination by cryptosporidium and giardia shed by deer mice is to determine the prevalence, levels, and genotypes of (oo)cysts in mouse feces. ... | 2017 | 28387527 |
| alteration of the α1β2/α2β1 subunit interface contributes to the increased hemoglobin-oxygen affinity of high-altitude deer mice. | deer mice (peromyscus maniculatus) that are native to high altitudes in the rocky mountains have evolved hemoglobins with an increased oxygen-binding affinity relative to those of lowland conspecifics. to elucidate the molecular mechanisms responsible for the evolved increase in hemoglobin-oxygen affinity, the crystal structure of the highland hemoglobin variant was solved and compared with the previously reported structure for the lowland variant. | 2017 | 28362841 |
| effects of seed density and proximity to refuge habitat on seed predation rates for a rare and a common lupinus species. | biotic interactions such as seed predation can play a role in explaining patterns of abundance among plant species. the effect of seed predation will depend on how the strength of predation differs across species and environments, and on the degree to which seed loss at one life-cycle phase increases fitness at another phase. few studies have simultaneously quantified predispersal and postdispersal predation in co-occurring rare and common congeners, despite the value of estimating both for unde ... | 2017 | 28325829 |
| the development of repetitive motor behaviors in deer mice: effects of environmental enrichment, repeated testing, and differential mediation by indirect basal ganglia pathway activation. | little is known about the mechanisms mediating the development of repetitive behaviors in human or animals. deer mice reared with environmental enrichment (ee) exhibit fewer repetitive behaviors and greater indirect basal ganglia pathway activation as adults than those reared in standard cages. the developmental progression of these behavioral and neural circuitry changes has not been characterized. we assessed the development of repetitive behavior in deer mice using both a longitudinal and coh ... | 2017 | 28181216 |
| acclimation to hypoxia increases carbohydrate use during exercise in high-altitude deer mice. | the low o2 experienced at high altitude is a significant challenge to effective aerobic locomotion, as it requires sustained tissue o2 delivery in addition to the appropriate allocation of metabolic substrates. here, we tested whether high- and low-altitude deer mice (peromyscus maniculatus) have evolved different acclimation responses to hypoxia with respect to muscle metabolism and fuel use during submaximal exercise. using f1 generation high- and low-altitude deer mice that were born and rais ... | 2017 | 28077391 |
| the ultimate and proximate mechanisms driving the evolution of long tails in forest deer mice. | understanding both the role of selection in driving phenotypic change and its underlying genetic basis remain major challenges in evolutionary biology. here, we use modern tools to revisit a classic system of local adaptation in the north american deer mouse, peromyscus maniculatus, which occupies two main habitat types: prairie and forest. using historical collections, we find that forest-dwelling mice have longer tails than those from nonforested habitat, even when we account for individual an ... | 2017 | 27958661 |
| changes in trap temperature as a method to determine timing of capture of small mammals. | patterns of animal activity provide important insight into hypotheses in animal behavior, physiological ecology, behavioral ecology, as well as population and community ecology. understanding patterns of animal activity in field settings is often complicated by the need for expensive equipment and time-intensive methods that limit data collection. because animals must be active to be detected, the timing of detection (e.g., the timing of capture) may be a useful proxy for estimation of activity ... | 2016 | 27792770 |
| cost and effectiveness of commercially available nesting substrates for deer mice (peromyscus maniculatus). | provision of nesting material promotes species-typical behaviors in rodents including deer mice (peromyscus maniculatus). the purpose of this study was to determine which commercially available nesting material best promotes complex nest building in the subspecies p. m. bairdii yet remains cost-effective for use as enrichment in a laboratory research setting. an existing breeding colony consisting of cages containing all male mice, all female mice, and breeding pairs was evaluated. five commerci ... | 2016 | 27423147 |
| functional genomic insights into regulatory mechanisms of high-altitude adaptation. | recent studies of indigenous human populations at high altitude have provided proof-of-principle that genome scans of dna polymorphism can be used to identify candidate loci for hypoxia adaptation. when integrated with experimental analyses of physiological phenotypes, genome-wide surveys of dna polymorphism and tissue-specific transcriptional profiles can provide insights into actual mechanisms of adaptation. it has been suggested that adaptive phenotypic evolution is largely mediated by cis-re ... | 2016 | 27343092 |
| transcriptomic plasticity in brown adipose tissue contributes to an enhanced capacity for nonshivering thermogenesis in deer mice. | for small mammals living at high altitude, aerobic heat generation (thermogenesis) is essential for survival during prolonged periods of cold, but is severely impaired under conditions of hypobaric hypoxia. recent studies in deer mice (peromyscus maniculatus) reveal adaptive enhancement of thermogenesis in high- compared to low-altitude populations under hypoxic cold stress, an enhancement that is attributable to modifications in the aerobic metabolism of muscles used in shivering. however, beca ... | 2016 | 27126783 |
| bohr effect and temperature sensitivity of hemoglobins from highland and lowland deer mice. | an important means of physiological adaptation to environmental hypoxia is an increased oxygen (o2) affinity of the hemoglobin (hb) that can help secure high o2 saturation of arterial blood. however, the trade-off associated with a high hb-o2 affinity is that it can compromise o2 unloading in the systemic capillaries. high-altitude deer mice (peromyscus maniculatus) have evolved an increased hb-o2 affinity relative to lowland conspecifics, but it is not known whether they have also evolved compe ... | 2016 | 26808972 |
| cranial morphological variation in peromyscus maniculatus over nearly a century of environmental change in three areas of california. | determining how species respond to prolonged environmental change is critical to understanding both their evolutionary biology and their conservation needs. in general, organisms can respond to changing environmental conditions by moving, by adapting in situ, or by going locally or globally extinct. morphological changes, whether plastic or adaptive, are one way that species may respond in situ to local environmental change. because cranial morphology is influenced by selective pressures arising ... | 2016 | 26511596 |
| correction: potential role of masting by introduced bamboos in deer mice (peromyscus maniculatus) population irruptions holds public health consequences. | | 2015 | 26039406 |
| adaptive modifications of muscle phenotype in high-altitude deer mice are associated with evolved changes in gene regulation. | at high-altitude, small mammals are faced with the energetic challenge of sustaining thermogenesis and aerobic exercise in spite of the reduced o2 availability. under conditions of hypoxic cold stress, metabolic demands of shivering thermogenesis and locomotion may require enhancements in the oxidative capacity and o2 diffusion capacity of skeletal muscle to compensate for the diminished tissue o2 supply. we used common-garden experiments involving highland and lowland deer mice (peromyscus mani ... | 2015 | 25851956 |
| rapid morphological change in black rats (rattus rattus) after an island introduction. | rapid morphological change has been shown in rodent populations on islands, including endemic deer mice (peromyscus maniculatus subspp.) on the california channel islands. surprisingly, most of these changes were towards a smaller size. black rats were introduced to anacapa island in the mid-1800s (probably in 1853) and eradicated in 2001-2002. to assess possible changes in these rats since their introduction, eleven cranial and four standard external measurements were taken from 59 rattus rattu ... | 2015 | 25780765 |
| high-altitude ancestry and hypoxia acclimation have distinct effects on exercise capacity and muscle phenotype in deer mice. | the hypoxic and cold environment at high altitudes requires that small mammals sustain high rates of o2 transport for exercise and thermogenesis while facing a diminished o2 availability. we used laboratory-born and -raised deer mice (peromyscus maniculatus) from highland and lowland populations to determine the interactive effects of ancestry and hypoxia acclimation on exercise performance. maximal o₂consumption (v̇o(2max)) during exercise in hypoxia increased after hypoxia acclimation (equival ... | 2015 | 25695288 |
| intraspecific polymorphism, interspecific divergence, and the origins of function-altering mutations in deer mouse hemoglobin. | major challenges for illuminating the genetic basis of phenotypic evolution are to identify causative mutations, to quantify their functional effects, to trace their origins as new or preexisting variants, and to assess the manner in which segregating variation is transduced into species differences. here, we report an experimental analysis of genetic variation in hemoglobin (hb) function within and among species of peromyscus mice that are native to different elevations. a multilocus survey of ... | 2015 | 25556236 |
| the relationship between cardiopulmonary size and aerobic performance in adult deer mice at high altitude. | deer mice (peromyscus maniculatus sonoriensis) populations in the white mountains of eastern california are found across a substantial range of partial pressures of oxygen (po₂). reduction in po₂ at high altitude can have a negative impact on aerobic performance. we studied plastic changes in organ mass and volume involved in aerobic respiration in response to acclimation to high altitude, and how those changes are matched with aerobic performance measured by vo₂,max. adult deer mice born and ra ... | 2014 | 25147245 |
| pleiotropic effects of a methyl donor diet in a novel animal model. | folate and other methyl-donor pathway components are widely supplemented due to their ability to prevent prenatal neural tube defects. several lines of evidence suggest that these supplements act through epigenetic mechanisms (e.g. altering dna methylation). primary among these are the experiments on the mouse viable yellow allele of the agouti locus (a(vy)). in the avy allele, an intracisternal a-particle retroelement has inserted into the genome adjacent to the agouti gene and is preferentiall ... | 2014 | 25121505 |
| the dynamics of sperm cooperation in a competitive environment. | sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear. here, we use fine-scale imaging and a minimal mathematical model to study sperm aggregation in the rodent genus peromyscus. we demonstrate that as the number of sperm cells in an aggregate increase, the group moves with more persistent linearity but without increasing speed. this benefit, however, is offset in larger aggr ... | 2014 | 25056618 |
| peromyscus (deer mice) as developmental models. | deer mice (peromyscus) are the most common native north american mammals, and exhibit great natural genetic variation. wild-derived stocks from a number of populations are available from the peromyscus genetic stock center (pgsc). the pgsc also houses a number of natural variants and mutants (many of which appear to differ from mus). these include metabolic, coat-color/pattern, neurological, and other morphological variants/mutants. nearly all these mutants are on a common genetic background, th ... | 2016 | 24896658 |
| effectiveness of rodenticides for managing invasive roof rats and native deer mice in orchards. | roof rats (rattus rattus) and deer mice (peromyscus maniculatus) are occasional pests of nut and tree fruit orchards throughout california and in many other parts of the usa and beyond. in general, the most practical and cost-effective control method for rodents in many agricultural environments is the use of rodenticides (toxic baits), but little or no information exists on the efficacy of current rodenticides in controlling roof rats and deer mice in orchards. therefore, our goals were to deve ... | 2014 | 24443051 |
| natural genetic variation underlying differences in peromyscus repetitive and social/aggressive behaviors. | peromyscus maniculatus (bw) and p. polionotus (po) are interfertile north american species that differ in many characteristics. for example, po exhibit monogamy and bw animals are susceptible to repetitive behaviors and thus a model for neurobehavioral disorders such as autism. we analyzed these two stocks as well as their hybrids, a bw y(po) consomic line (previously shown to alter glucose homeostasis) and a natural p. maniculatus agouti variant (a(nb) = wide band agouti). we show that po anima ... | 2014 | 24407381 |
| functional genomics of adaptation to hypoxic cold-stress in high-altitude deer mice: transcriptomic plasticity and thermogenic performance. | in species that are distributed across steep environmental gradients, adaptive variation in physiological performance may be attributable to transcriptional plasticity in underlying regulatory networks. here we report the results of common-garden experiments that were designed to elucidate the role of regulatory plasticity in evolutionary adaptation to hypoxic cold-stress in deer mice (peromyscus maniculatus). we integrated genomic transcriptional profiles with measures of metabolic enzyme activ ... | 2014 | 24102503 |
| terrestrial ecosystem recovery following removal of a pcb point source at a former pole vault line radar station in northern labrador. | saglek bay (lab-2), located on the northeast coast of labrador is a former polevault station that was operated by the u.s. air force from 1953 to 1971 when it was abandoned. an environmental assessment carried out in 1996 determined that the site was contaminated with polychlorinated biphenyls (pcbs) with concentrations in soils far exceeding the canadian environmental protection agency (cepa) regulation of 50 μg/g in three areas of the site (beach, site summit, antenna hill). this led to remedi ... | 2013 | 23712118 |
| improved technique for induction and monitoring of audiogenic seizure in deer mice. | epilepsy is a debilitating disease characterized by recurring seizures. epilepsy can be studied using animal models, such as rodents prone to audiogenic seizure (ags), which experience generalized seizures (loss of consciousness accompanied by rhythmic muscle spasms and rigid muscle stiffness) after intense sound stimulation. in 1933, a spontaneous mutation resulting in sensitivity to ags was observed among laboratory stocks of deer mice (peromyscus maniculatus artemisiae) at the university of m ... | 2013 | 23604158 |
| phenotypic plasticity in blood-oxygen transport in highland and lowland deer mice. | in vertebrates living at high altitude, arterial hypoxemia may be ameliorated by reversible changes in the oxygen-carrying capacity of the blood (regulated by erythropoiesis) and/or changes in blood-oxygen affinity (regulated by allosteric effectors of hemoglobin function). these hematological traits often differ between taxa that are native to different elevational zones, but it is often unknown whether the observed physiological differences reflect fixed, genetically based differences or envir ... | 2013 | 23239893 |
| contributions of phenotypic plasticity to differences in thermogenic performance between highland and lowland deer mice. | small mammals face especially severe thermoregulatory challenges at high altitude because the reduced o2 availability constrains the capacity for aerobic thermogenesis. adaptive enhancement of thermogenic performance under hypoxic conditions may be achieved via physiological adjustments that occur within the lifetime of individuals (phenotypic plasticity) and/or genetically based changes that occur across generations, but their relative contributions to performance differences between highland a ... | 2013 | 23197099 |
| sex and dose-dependent effects of developmental exposure to bisphenol a on anxiety and spatial learning in deer mice (peromyscus maniculatus bairdii) offspring. | bisphenol a (bpa) is a widely produced, endocrine disrupting compound that is pervasive in the environment. data suggest that developmental exposure to bpa during sexual differentiation of the brain leads to later behavioral consequences in offspring. outbred deer mice (peromyscus maniculatus bairdii) are an excellent animal model for such studies as they exhibit well-defined sex- and steroid-dependent behaviors. here, dams during gestation and lactation were fed with a phytoestrogen-free contro ... | 2013 | 23051835 |
| postdispersal seed predation limits the abundance of a long-lived perennial forb (lithospermum ruderale). | loss of seeds to consumers is common in plant communities, but the degree to which these losses influence plant abundance or population growth is often unclear. this is particularly the case for postdispersal seed predation by rodents, as most studies of rodent seed predation have focused on the sources of spatiotemporal variation in seed loss but not quantified the population consequences of this loss. in previous work we showed that seed predation by deer mice (peromyscus maniculatus) substant ... | 2012 | 22624208 |
| biotic resistance via granivory: establishment by invasive, naturalized, and native asters reflects generalist preference. | escape from specialist natural enemies is frequently invoked to explain exotic plant invasions, but little attention has been paid to how generalist consumers in the recipient range may influence invasion. we examined how seed preferences of the widespread generalist granivore peromyscus maniculatus related to recruitment of the strongly invasive exotic centaurea stoebe and several weakly invasive exotics and natives by conducting laboratory feeding trials and seed addition experiments in the fi ... | 2011 | 21939071 |
| a unique late-replicating xy to autosome translocation in peromyscus melanophrys. | we report on the characterization of the peromyscus melanophrys karyotype and sex chromosome system. classic studies reported the sex chromosome system of this species may be as complex as an x(1)x(1)x(2)x(2)/x(1)x(2)y(1)y(2) and provided conflicting identification of the x chromosome. using peromyscus maniculatus chromosome paints, we have positively identified the sex chromosomes and clarified the sex determining system that once perplexed peromyscus researchers. the sex chromosomes are charac ... | 2010 | 20177772 |
| microsatellite variation and evolution in the peromyscus maniculatus species group. | variation at 12 pure-repeat dinucleotide microsatellites from peromyscus maniculatus was analyzed for samples of all species in the p. maniculatus species group and p. leucopus. except for one locus (pml08) that amplified a product only for p. maniculatus, these microsatellites yielded reliable estimates of variation across these species; per-locus polymorphism and allele-size distribution were not significantly different among or between any of the species sampled from mainland populations. sig ... | 2005 | 15619451 |
| natural selection drives altitudinal divergence at the albumin locus in deer mice, peromyscus maniculatus. | in populations that are distributed across steep environmental gradients, the potential for local adaptation is largely determined by the spatial scale of fitness variation relative to dispersal distance. since altitudinal gradients are generally characterized by dramatic ecological transitions over relatively short linear distances, adaptive divergence across such gradients will typically require especially strong selection to counterbalance the homogenizing effect of gene flow. here we report ... | 2004 | 15266982 |
| relative roles of mutation and recombination in generating allelic polymorphism at an mhc class ii locus in peromyscus maniculatus. | the mhc class ii loci encoding cell surface antigens exhibit extremely high allelic polymorphism. there is considerable uncertainty in the literature over the relative roles of recombination and de novo mutation in generating this diversity. we studied class ii sequence diversity and allelic polymorphism in two populations of peromyscus maniculatus, which are among the most widespread and abundant mammals of north america. we find that intragenic recombination (or gene conversion) has been the p ... | 2003 | 14768893 |
| maximal aerobic performance of deer mice in combined cold and exercise challenges. | in nature, animals frequently need to deal with several physiological challenges simultaneously. we examined thermoregulatory performance (body temperature stability) and maximal oxygen consumption of deer mice (peromyscus maniculatus) during intense exercise at room temperature, acute cold exposure, and exercise during cold exposure. results with exercise and cold exposure alone were consistent with previous studies: there was little difference between maximal metabolism elicited by exercise al ... | 2004 | 14569409 |
| testicular histopathology in deer mice (peromyscus maniculatus) following exposure to polychlorinated biphenyl. | adult deer mice testes were subjected to routine histopathology following exposure to aroclor 1254 supplemented diet (5 ppm), for 30 days. body and testicular weight revealed no statistical significance between the control and treated animals. from a histological standpoint the testes of the controls were similar to normal murids and other animals. in contrast, the testes from treated animals displayed seminiferous tubules with significant degenerative alterations. these alterations included few ... | 2003 | 12729713 |
| spontaneous gallstone formation in deer mice: interaction of cholesterol, bile acids, and dietary fiber. | a study of the physiologic and ecologic factors involved in a spontaneous seasonal gallstone cycle of deer mice (peromyscus maniculatus gambelii) was conducted at the tulelake national wildlife refuge (california, usa) from march 1991 to june 1992. the specific hypothesis examined was whether or not seasonal increases in dietary fiber intake provides the necessary conditions for a solubility defect, or supersaturation mechanism, resulting in precipitation of cholesterol gallstones. results indic ... | 2003 | 12685073 |
| age and aerobic performance in deer mice. | age impacts the phenotype of all multicellular animals, but lifetime changes in physiological traits are poorly understood for all but a few species. here, we describe a cross-sectional study of age effects on body composition, aerobic performance and ventilation in deer mice peromyscus maniculatus. this species lives considerably longer in captivity (in excess of 5 years) than most laboratory rodents, and the adaptational biology of its aerobic physiology is well studied. our deer mice grew thr ... | 2003 | 12604582 |
| effects of in utero and lactational ammonium perchlorate exposure on thyroid gland histology and thyroid and sex hormones in developing deer mice (peromyscus maniculatus) through postnatal day 21. | thyroid gland hormone levels and histology and sex hormone levels in developing deer mice (peromyscus maniculatus) were measured following in utero and lactational exposure to ammonium perchlorate (ap), a component of rocket fuel and a thyroid toxicant. breeding pairs were dosed continuously with 0, 1 nm, 1 micro m, or 1 mm concentrations of ap in drinking water from the time of cohabitation until pups from the third litter were weaned. pups from the second litter were used for evaluation in thi ... | 2002 | 12515590 |
| developmental plasticity in aerobic performance in deer mice (peromyscus maniculatus). | while several studies have examined the abiotic effects of altitude (low ambient temperatures and hypoxia) on the aerobic performance of small mammals, few have explored the effects of development and maturation at different altitudes on aerobic performance as adults. we examined the basal metabolism and aerobic performance of deer mice (peromyscus maniculatus) under four different developmental and testing regimes: (1) reared (gestation through weaning) and tested at high altitude; (2) reared a ... | 2002 | 12208296 |
| in utero and lactational exposure to ammonium perchlorate in drinking water: effects on developing deer mice at postnatal day 21. | the effects of in utero and lactational exposure to ammonium perchlorate (ap), a component of rocket fuel and a thyroid toxicant, on developing deer mice (peromyscus maniculatus) were evaluated. breeding pairs were dosed continuously with 0, 1 nm, 1 micro m, or 1 mm ap in drinking water, from cohabitation until pups were euthanized at postnatal day (pnd) 21. pups from the second litter were used for evaluation in this study. no significant differences were observed in any analysis performed when ... | 2002 | 12167219 |
| fecal corticosteroids in agouti and non-agouti deer mice (peromyscus maniculatus). | total and per gram fecal corticosteroid concentrations were determined for agouti and non-agouti deer mice (peromyscus maniculatus gracilis) over 24 h under normal caging conditions and after exposure to the stress of novel caging. per gram corticosteroid concentrations, fecal output, and 24-h corticosteroid production were greater in stressed compared with unstressed deer mice of both color morphs, whereas stressed agoutis had a greater increase in per gram corticosteroid concentrations when co ... | 2002 | 12020660 |
| dissociation between spontaneously emitted and apomorphine-induced stereotypy in peromyscus maniculatus bairdii. | stereotyped behavior is repetitive, topographically invariant motor activity that lacks an obvious function. we have previously characterized the spontaneous and persistent stereotypies that occur in deer mice housed in standard laboratory cages. providing these animals with enriched environments markedly reduces their vulnerability to develop stereotypic behavioral repertoires, thus enabling us to generate behaviorally distinct (stereotypic and nonstereotypic) mice of the same species. as stere ... | 2002 | 11897261 |
| spontaneous "regression" of enhanced immune function in a photoperiodic rodent peromyscus maniculatus. | short days inhibit reproduction and enhance immune function in deer mice (peromyscus maniculatus). their reproductive inhibition is sustained by an endogenous timing mechanism: after ca. 20 weeks in short days, reproductive photorefractoriness develops, followed by spontaneous recrudescence of the reproductive system. it is unknown whether analogous seasonal timing mechanisms regulate their immune function or whether enhanced immune function is sustained indefinitely under short days. in order t ... | 2001 | 11674869 |
| body and organ mass in agouti and non-agouti deer mice (peromyscus maniculatus). | body, adrenal, brain, heart, liver, kidney, spleen and testis masses were determined for agouti and non-agouti deer mice (peromyscus maniculatus gracilis) of both sexes. body mass was highest for non-agouti females and lowest for agouti females; and sex differences in body mass were significant for agouti, but not non-agouti, deer mice. adrenal, brain and liver masses were similar between color morphs; heart mass was greater in agouti males; and kidney, spleen and testis masses were all signific ... | 2001 | 11544076 |
| thyroxine levels in agouti and non-agouti deer mice (peromyscus maniculatus). | total thyroxine was assessed by radioimmunoassay for 58 female deer mice of two subspecies (peromyscus maniculatus bairdii and p. m. gracilis) and two color morphs (agouti and non-agouti). p. m. bairdii of both color-morphs had significantly higher mean thyroxine levels than p. m. gracilis. non-agouti deer mice of both subspecies had significantly higher mean thyroxine levels than agouti deer mice. this is the first report of thyroid hormone differences associated with the non-agouti allele. | 2001 | 11544074 |
| effects of altitude and temperature on organ phenotypic plasticity along an altitudinal gradient. | small mammals living in high-altitude environments must endure decreased ambient temperatures and hypoxic conditions relative to sea-level environments. previously, it was noted that heart, lung and digestive tract masses and blood hematocrit increase along an altitudinal gradient in small mammals. increases in digestive organ mass were attributed to lower ambient temperatures and greater food intake, and increases in lung mass and hematocrit were attributed to hypoxia, but these assumptions wer ... | 2001 | 11441040 |
| a novel mechanism of body mass regulation. | while significant attention has been devoted to the identification of hormonal factors that control body mass, little attention has been paid to the role of mechanical loading on animal mass. here, we provide evidence that intraperitoneal implantation of metabolically inert mass results in a compensatory reduction in tissue mass. deer mice (peromyscus maniculatus) were surgically implanted with weights of 1, 2 or 3 g. there was a resulting loss of tissue mass (total body mass minus implant mass) ... | 2001 | 11316493 |
| oxygen consumption and carbon dioxide production in male prairie deermice (peromyscus maniculatus bairdii) in different reproductive conditions and group densities. | natural and laboratory populations of peromyscus exhibit a profound but reversible reproductive inhibition related to population density. our earlier studies described the endocrine physiology of inhibited animals which resembles a condition of delayed puberty, but they did not reveal a primary mechanism for the induction and maintenance of the inhibition. these studies indicated that reproductive inhibition could be associated with an overall change in general metabolism. to test this hypothesi ... | 1998 | 11253796 |
| genetic (rapd) diversity in peromyscus maniculatus populations in a naturally fragmented landscape. | we assessed the effects of long-term habitat fragmentation on genetic (random amplified polymorphic dna) diversity in 11 peromyscus maniculatus populations in the lake superior watershed. we analysed genetic structure at two spatial scales and the effect of island size and isolation on genetic diversity. at the regional scale, island populations differed from mainland populations (fst = 0.36), but mainland populations did not differ from each other (fst = 0.01). at the local scale, populations o ... | 2001 | 11251785 |
| responses to lactation and cold exposure by deer mice (peromyscus maniculatus). | recently, much interest has been expressed in understanding how animals use phenotypic plasticity of tissue size and function to meet increased metabolic demands. we set out to learn (i) whether female deer mice (peromyscus maniculatus) given lactation (two to seven pups per litter), cold (5 degrees c), or cold plus lactation as energy demands display phenotypic plasticity in organ size and function; (ii) whether that plasticity is similar to laboratory mice given the same demands; and (iii) whe ... | 2008 | 11073789 |
| genetic and epigenetic incompatibilities underlie hybrid dysgenesis in peromyscus. | crosses between the two north american rodent species peromyscus polionotus (po) and peromyscus maniculatus (bw) yield parent-of-origin effects on both embryonic and placental growth. the two species are approximately the same size, but a female bw crossed with a male po produces offspring that are smaller than either parent. in the reciprocal cross, the offspring are oversized and typically die before birth. rare survivors are exclusively female, consistent with haldane's rule, which states tha ... | 2000 | 10802670 |
| morphological and physiological responses to altitude in deer mice peromyscus maniculatus. | individuals within a species, living across a wide range of habitats, often display a great deal of phenotypic plasticity for organ mass and function. we investigated the extent to which changes in organ mass are variable, corresponding to environmental demand, across an altitudinal gradient. are there changes in the mass of oxygen delivery organs (heart and lungs) and other central processing organs (gut, liver, kidney) associated with an increased sustainable metabolic rate that results from d ... | 2006 | 10521329 |
| rapid morphological change in channel island deer mice. | deer mice, peromyscus maniculatus, collected over 90 years from three california channel islands, were examined for evidence of morphological change. rapid morphological change has occurred in the endemic subspecies from santa barbara (p. m. elusus), anacapa (p. m. anacapae), and santa cruz island (p. m. santacruzae). data were divided into two temporal classes, 1897-1941 and 1955-1988. of the 16 morphological characters measured, between five and 10 measures changed significantly (p ⩽ 0.05) wit ... | 1999 | 28565559 |
| natural selection on thermogenic capacity of high-altitude deer mice. | adaptive explanations that rely on physiological arguments are common, but tests of hypotheses about the significance of whole-animal physiological performance (e.g., aerobic capacities) are rare. we studied phenotypic selection on the thermogenic capacity (i.e., maximal rate of oxygen consumption [vo2 max] elicited via cold exposure) of high-altitude (~3800 m) deer mice (peromyscus maniculatus). a high vo2 max equates to a high capacity for heat production and should favor survival in the cold ... | 1999 | 28565539 |
| phenotypic differences in the gnrh neuronal system of deer mice peromyscus maniculatus under a natural short photoperiod. | the neural mechanisms by which short photoperiod induces gonadal regression among seasonally breeding mammals are not well understood. one hypothesis suggests that the proximate cause of seasonal gonadal regression is a photoperiod-induced modification in gnrh secretion. this hypothesis is indirectly supported by our recent findings using immunocytochemistry which identified specific photoperiod-induced adjustments in the number and morphology of gnrh containing neurones between reproductively c ... | 1998 | 10070352 |
| genomic imprinting is disrupted in interspecific peromyscus hybrids. | genomic imprinting, the unequal expression of gene alleles on the basis of parent of origin, is a major exception to mendelian laws of inheritance. by maintaining one allele of a gene in a silent state, imprinted genes discard the advantages of diploidy, and for this reason the rationale for the evolution of imprinting has been debated. one explanation is the parent-offspring conflict model, which proposes that imprinting arose in polyandrous mammals as the result of a parental conflict over the ... | 1998 | 9843208 |
| short photoperiod affects reproductive function but not dehydroepiandrosterone concentrations in male deer mice (peromyscus maniculatus). | cessation of breeding is central among the suite of winter-coping strategies used by small rodents to survive energy-demanding winter conditions. animals use photoperiod to predict the onset of winter and initiate, well in advance of deteriorating conditions, seasonal adaptations. exposure to short photoperiod leads to regression of the reproductive system in long-day breeding animals. likewise, exposure to short days leads to enhanced immune function among several rodent species studied. becaus ... | 1998 | 9755031 |
| short-day enhancement of immune function is independent of steroid hormones in deer mice (peromyscus maniculatus). | the effects of photoperiod and steroid hormones on immune function were assessed in male and female deer mice (peromyscus maniculatus). in experiment 1, male deer mice were castrated, castrated and given testosterone replacement, or sham-operated. half of each experimental group were subsequently housed in either long (ld 16:8) or short days (ld 8:16) for 10 weeks. short-day deer mice underwent reproductive regression and displayed elevated lymphocyte proliferation in response to the t-cell mito ... | 1998 | 9747522 |
| spatial learning and hippocampal volume in male deer mice: relations to age, testosterone and adrenal gland weight. | spatial learning and various physiological parameters were examined in old (57 month), middle aged (38 month), adult (18 month) and young (3-3.5 month) male deer mice (peromyscus maniculatus). performance during acquisition of a water maze task was not significantly reduced for middle aged and adult mice relative to young reproductively active (breeding) mice. performance was deteriorated in old mice relative to young breeding mice on block 4 of training. retention of this spatial task, however, ... | 1998 | 9697116 |
| photoperiod, ambient temperature, and food availability interact to affect reproductive and immune function in adult male deer mice (peromyscus maniculatus). | winter is often stressful. increased energetic demands in winter and concurrent reductions in energy availability can lead to an energetic imbalance and compromise survival. to increase the odds of surviving winter, individuals of some nontropical rodent species have evolved mechanisms to enhance immune function in advance of harsh winter conditions. short day lengths provide a proximate cue for enhancement of immune function, an adaptive functional response to counter environmental stress-induc ... | 1998 | 9615289 |
| exogenous melatonin enhances cell-mediated, but not humoral, immune function in adult male deer mice (peromyscus maniculatus). | many nontropical rodent species display seasonal changes in reproductive physiology and metabolism, as well as in immune function. field studies of seasonal changes in immune function typically report decreased immune function in the short days of winter compared to summer; presumably, reduced immunity in winter reflects increased glucocorticoid secretion in response to environmental stressors. in contrast, laboratory studies of photoperiodic changes in immunity invariably demonstrate increased ... | 1998 | 9615288 |
| effect of transatlantic transport on reproduction of agouti and nonagouti deer mice, peromyscus maniculatus. | in conjunction with establishing colonies of deer mice in the uk, effects of transportation on reproduction in agouti (a) and nonagouti (a) deer mice were assessed. adults were shipped via ground courier and air freight from northampton, massachusetts, usa to sutton bonington, leicestershire, england in february and june. deer mice were paired upon arrival in sutton bonington, whereas matched controls were paired in the original colonies at shipping. to assess reproduction, the following variabl ... | 1998 | 9481695 |
| the effects of photoperiod and food intake on reproductive development in male deer mice (peromyscus maniculatus). | seasonal breeding is a tactic that has evolved in rodents that limits reproduction to specific times of the year to increase reproductive success. in order to time breeding accurately, many animals respond to changes in daily photoperiod. short day lengths inhibit breeding in many nontropical rodent species. restricted food availability can also inhibit reproductive function among some individuals in these so-called "photoperiodic" populations. rodents born at the end of the breeding season typi ... | 1997 | 9333185 |