Publications

TitleAbstractYear
Filter
PMID
Filter
female prairie voles (microtus ochrogaster) fail to form a new pair after loss of mate.we tested experimentally the hypothesis that failure to acquire a new mate by monogamously paired female microtus ochrogaster that lose their mate represents pair-bonding behavior, not a lack of available males. males were removed from reproductive male-female pairs and the females provided an opportunity to pair with unfamiliar sexually inexperienced or experienced males in a semi-natural arena. only three of 22 (13.6%) females formed a new pair, two with inexperienced males and one with an exp ...199824897643
neuroendocrine bases of monogamy.a number of studies have implicated the neurohypophyseal peptides oxytocin and vasopressin in the central mediation of complex social behaviors, including affiliation, parental care and territorial aggression. research on a monogamous rodent, the prairie vole (microtus ochrogaster), suggests that these neuropeptides are also involved in the control of several behaviors associated with monogamy, including pair bonding, paternal care and mate guarding. comparative studies using several species of ...19989498302
effects of the selective serotonin reuptake inhibitor fluoxetine on social behaviors in male and female prairie voles (microtus ochrogaster).the selective serotonin reuptake inhibitor fluoxetine modifies social behavior in a number of species, including humans. because the neural substrates for social behavior in prairie voles are sexually dimorphic, we tested whether the effects of fluoxetine on these behaviors differ by sex. parental and pair-bonded voles were chronically treated with fluoxetine or saline and subsequently tested for parental responsiveness. fluoxetine-treated animals displayed a longer latency to exhibit parental r ...19979454669
amygdala but not hippocampal lesions impair olfactory memory for mate in prairie voles (microtus ochrogaster).exposure to an unfamiliar male conspecific results in pregnancy interruption (i.e., the bruce effect) in rodents. unlike most laboratory rodents, female prairie voles (microtus ochrogaster) are induced into estrus by chemosensory stimuli contained in the urine of male conspecifics while grooming the anogenital (a-g) region of unfamiliar males. female prairie voles maintain a brief "memory" for the stud male for 8-10 days after mating. subsequent exposure to the same mate within this 8- to 10-day ...19979374810
sexual and social experience is associated with different patterns of behavior and neural activation in male prairie voles.monogamous prairie voles (microtus ochrogaster) show mating-induced aggression towards conspecific strangers. this behavior is both selective and enduring. the present study was designed to investigate the behavioral conditions for the emergence of selective aggression (by varying prior experience with a female and identity of intruders) and the limbic activation in response to an intruder (by mapping regional staining for c-fos) in male prairie voles. in a first experiment, males that mated wit ...19979367264
exposure to male siblings facilitates the response to estradiol in sexually naive female prairie voles.female prairie voles undergo induced estrus, and require both physical contact with males and exposure to male urine to become reproductively active. this study attempted to determine if physical contact with males enhanced female response to estradiol. two groups of sexually naive females were tested. one was reared without any exposure to males after weaning, and the other was reared with sibling males to 60 days of age. sibling males were used because females avoid direct contact with the uri ...19979177571
high-affinity binding of corticosterone to mammalian neuronal membranes: possible role of corticosteroid binding globulin.the signal transduction mechanisms mediating rapid steroid actions are poorly understood. to characterize corticosteroid interaction with neuronal membranes in a species with rapid behavioral responses to corticosterone, we examined [3h]corticosterone binding to membranes prepared from prairie vole brains. at 22 degrees c, the rates of association and dissociation of [3h]corticosterone with well-washed synaptosomal membranes were very rapid. specific binding was characterized by high affinity (k ...19979191981
exploratory behavior correlates with social organization and is responsive to peptide injections in prairie voles. 19979071412
perinatal hormone exposure alters the expression of selective affiliative preferences in prairie voles.in the present study, perinatal administration of corticosterone and testosterone significantly influenced affiliative preferences only in females. despite the very high levels of steroids given, no significant differences were noted among treated and untreated groups of males. prairie voles apparently are uniquely adapted to tolerate high levels of endogenous steroids. however, females of this species may be capable of exploiting variations in corticosterone levels to regulate sexually dimorphi ...19979071399
intraspecific variation and the presence of a father can influence the expression of monogamous and communal traits in prairie voles. 19979071398
the 5' flanking region of the monogamous prairie vole oxytocin receptor gene directs tissue-specific expression in transgenic mice. 19979071386
differential fos expression following microinjection of oxytocin or vasopressin in the prairie vole brain. 19979071383
social modulation of corticosteroid responses in male prairie voles. 19979071380
perinatal steroid treatments alter alloparental and affiliative behavior in prairie voles.this experiment was designed to examine the hypothesis that perinatal manipulation of gonadal or adrenal steroids can alter the subsequent expression of juvenile parental (alloparenting) and affiliative behavior in prairie voles (microtus ochrogaster). corticosterone (precort), testosterone (pre-tp), or oil injections (preses) were given on prenatal days 12-20 or on postnatal days 1-6 (cort6, tp6, or ses6, respectively). alloparenting was reduced significantly in females in the cort6 group and i ...19969047281
social isolation in animal models of relevance to neuropsychiatric disorders.animal models of social isolation have been suggested to be relevant to several neuropsychiatric disorders; however, social isolation is usually not purely an alteration of social environment, as it often involves such factors as decreased complexity of the environment, loss of tactile stimulation, and increased metabolic demands of temperature maintenance. in this study, female prairie voles (microtus ochrogaster, a highly social rodent) were assigned to four experimental groups: continued hous ...19968896780
the effects of stress on social preferences are sexually dimorphic in prairie voles.prairie voles (microtus ochrogaster) are monogamous rodents that form pair bonds characterized by a preference for a familiar social partner. in male prairie voles, exposure to either the stress of swimming or exogenous injections of corticosterone facilitate the development of a social preference for a female with which the male was paired after injection or swimming. conversely, adrenalectomy inhibits partner preference formation in males and the behavioral effects of adrenalectomy are reverse ...19968876248
effects of estradiol on sexual receptivity, wheel-running behavior, and vaginal estrus in virgin prairie voles.this study examined the effects of estradiol on sexual receptivity and vaginal estrus in experienced and virgin female prairie voles, and running wheel activity in virgin females. because prairie voles undergo induced ovulation, we predicted that exogenous estradiol would not affect activity patterns nor stimulate lordosis in virgins. females were sc injected with estradiol benzoate (ed) and placed with males, and sexual receptivity was monitored. in experienced females 0.5 micrograms of eb resu ...19968873258
gonadal and photoperiodic influences on body mass regulation in adult male and female prairie voles.nontropical animals commonly use the annual change in photoperiod to phase seasonal adjustments that promote survival and reproduction. to cope with the energetic requirements of winter, many rodents alter body mass in anticipation of winter. photoperiodic adjustments are often mediated by the pineal hormone melatonin; melatonin can exert a primary effect on body mass or secondarily affect body mass by changing blood gonadal steroid levels. the present study sought to determine if prairie voles ...19968928899
photoperiod and population density interact to affect reproductive and immune function in male prairie voles.seasonal breeding of rodents is often associated with changes in adrenal function; altered adrenal function could account, in part, for seasonal changes in immune function and, ultimately, influence seasonal fluctuations in survival. animals commonly monitor the annual change in photoperiod to ascertain the time of year and to make appropriate seasonal adjustments in physiology and behavior. several extrinsic factors affect reproductive responsiveness to photoperiod. the interaction between popu ...19968780222
estradiol concentration and the regulation of locomotor activity.we predicted that female prairie voles (microtus ochrogaster) would not increase in locomotor activity during "induced" proestrus. we developed and tested two alternative a priori hypotheses to explain this predicted lack of activity. the non-response hypothesis in which voles cannot, physiologically, increase activity in response to estradiol and, the threshold effect hypothesis in which a minimal concentration of estradiol is necessary to achieve estrus, while higher concentrations influence o ...19958577893
photoperiodic effects on steroid negative feedback in female prairie voles (microtus ochrogaster).breeding in prairie voles is mainly restricted to the autumn and winter of most years. the organization of estrus in female prairie voles is unusual because behavioral estrus is induced by chemosensory stimuli from the urine of adult conspecific males. isolated females exhibit undetectable levels of estradiol and never display estrous behavior, yet exposure to male urine causes a cascade of endocrine changes that evoke estrogen secretion from the ovaries and estrous behavior within 24 hr. in the ...19958575664
interaction of male sensory cues and estradiol in the induction of estrus in the prairie vole.in the prairie vole, estrus and ovulation are induced by stimulation from a male, which also increases the female's gonadal weight and serum estradiol level. it is not known whether the induction of receptivity is dependent solely on an endogenous increase in circulating estradiol or an interaction of increased estradiol and male sensory stimulation. using a dose response paradigm, we examined if a dose of estradiol within physiological range was sufficient to induce receptivity. we also examine ...19958559792
modulation of pair bonding in female prairie voles (microtus ochrogaster) by corticosterone.glucocorticoid levels in animals may respond to and influence the development of social attachments. this hypothesis was tested in prairie voles (microtus ochrogaster), monogamous rodents that form long-term heterosexual pair bonds. in socially naive female prairie voles, cohabitation with an unfamiliar male resulted in a dramatic decline in serum corticosterone levels. when corticosterone levels were reduced via adrenalectomy, females developed partner preferences after 1 h of cohabitation, whi ...19957644488
a gender-specific mechanism for pair bonding: oxytocin and partner preference formation in monogamous voles.previous studies have demonstrated that central administration of vasopressin but not oxytocin facilitates pair bonding in the monogamous male prairie vole. this study tested vasopressin and oxytocin in the formation of the female vole's preference for a particular male partner. initial studies showed that in monogamous female prairie voles (but not in nonmonogamous congeners), mating was followed by a partner preference that endured for at least 2 weeks. nonmating prairie vole females developed ...19957576222
role of male proximity in pregnancy maintenance in prairie voles, microtus ochrogaster.three experiments were conducted to determine whether the presence of a male partner during the gestation period facilitates pregnancy maintenance in female prairie voles. in each of the three experiments more females delivered litters when the male was present and separated from them by a wire-mesh barrier than when the male was absent. the effect was present in both nulliparous and parous females. at the ultimate level this suggests a constraint on male mating strategies. at the proximate leve ...19957610130
the effects of photoperiod on olfactory c-fos expression in prairie voles, microtus ochrogaster.reproduction stops among the majority of prairie voles (microtus ochrogaster) during the winter. short day lengths suppress male reproductive function dramatically in the laboratory, but photoperiod exerts only subtle effects on female reproductive function. thus, the regulation of seasonal breeding in this species remains partially unspecified. in contrast to commonly studied rodents, female prairie voles do not undergo spontaneous estrous cycles; rather, they are induced into estrus by exposur ...19957606471
physiological substrates of mammalian monogamy: the prairie vole model.prairie voles (microtus ochrogaster) are described here as a model system in which it is possible to examine, within the context of natural history, the proximate processes regulating the social and reproductive behaviors that characterize a monogamous social system. neuropeptides, including oxytocin and vasopressin, and the adrenal glucocorticoid, corticosterone, have been implicated in the neural regulation of partner preferences, and in the male, vasopressin has been implicated in the inducti ...19957630584
cohabitation alters vasopressin innervation and paternal behavior in prairie voles (microtus ochrogaster).the density of vasopressin-immunoreactive (avp-ir) fibers in the lateral septum and lateral habenular nucleus is lower in prairie vole fathers--which display paternal behavior under natural conditions-than in sexually naive males. to see if these changes occur before or after the birth of pups, and whether they are related to changes in paternal behavior, we tested paternal responsiveness and measured avp-ir fiber density in the lateral septum, lateral habenular nucleus, medial preoptic area, an ...19947800744
limbic system fos expression associated with paternal behavior.axon-sparing lesions of the medial nucleus of the amygdala (mea) decrease male parental behavior in the highly social prairie vole. to assess further the role of the amygdala in paternal behavior, male and female prairie voles were exposed to a pup or a non-social olfactory stimulus for 3 hours, and cells expressing fos peptide were labelled using immunocytochemistry. compared to controls, males exposed to a pup showed an increase in fos expression in the mea, as well as in several areas with co ...19947834331
sexual maturation in male prairie voles: effects of the social environment.the effects of various social contexts on sexual maturation in captive male prairie voles were investigated. sexual maturity was assessed as the ability of a young male to produce urine capable of activating a diestrous adult female into estrus, as females remain anestrus until they ingest a male urinary chemosignal. in five experiments the postweaning social environments of developing males were manipulated (e.g., presence or absence of dam, sire, or junior litter, exposure to unfamiliar adult ...19947938241
day length influences proceptive behavior of female prairie voles (microtus ochrogaster).prairie voles typically do not breed during the winter; instead, they typically confine breeding to the spring and summer. one proximate cue contributing to this seasonal change in breeding among males is photoperiod. however, photoperiod does not appear to affect female fecundity. female prairie voles are induced into estrus by chemosensory cues in the urine of male conspecifies. females are exposed to these cues when they groom the ano-genital region of males. females that do not groom the ano ...19948047587
place learning by three vole species (microtus ochrogaster, m. montanus, and m. pennsylvanicus) in the morris swim task.place learning was assessed in three species of voles (microtus ochrogaster, m. montanus, and m. pennsylvanicus) with the morris swim task. the performance of all 3 species and both sexes improved with training on the hidden-platform version of the morris swim task, which indicates that all groups were able to learn to locate a spatial goal without local cues. contrary to expectations, no evidence for a sex difference in spatial ability emerged in any of the species. these findings do not provid ...19948026170
oxytocin administered centrally facilitates formation of a partner preference in female prairie voles (microtus ochrogaster).prairie voles (microtus ochrogaster) are monogamous mammals that form male-female pair bonds. partner preference formation, one component of the pair bond in prairie voles, occurs following male-female cohabitation and is facilitated by mating. the peptide hormone oxytocin is released during physical contact and particularly following vaginal stimulation. oxytocin has been implicated in mother-infant bond formation. the present study tested the hypothesis that oxytocin participates in the partne ...19947920590
axon-sparing lesions of the medial nucleus of the amygdala decrease affiliative behaviors in the prairie vole (microtus ochrogaster): behavioral and anatomical specificity.the neural basis of affiliative behavior was examined in the prairie vole, a rodent that exhibits high levels of social contact and paternal behavior. in the first study, the axon-sparing excitotoxin n-methyl-d,l-aspartic acid (nma) produced lesions in the basolateral nucleus of the amygdala or the corticomedial amygdala. males with corticomedial lesions showed significantly less contact with a familiar adult female and a pup when compared with males with lesions of the basolateral nucleus or co ...19947917044
olfactory bulbectomy decreases social behavior in male prairie voles (m. ochrogaster).prairie voles (microtus ochrogaster) are social rodents that show characteristics of monogamy including high levels of social behavior and male parental care. behavioral studies of prairie voles have implicated chemosignals in the control of various components of social behavior and reproduction. in the present study, the role of the olfactory system in male behavior was examined following surgical removal of the olfactory bulbs. decreases in measures of sexual, paternal, and other social behavi ...19948022909
removal of the vomeronasal organ reduces reproductive performance and aggression in male prairie voles.several short-duration tests have demonstrated that the surgical removal of the vomeronasal organ (vnx) from sexually-inexperienced male rodents results in a reduction in copulatory behavior, compared to the effects of sham surgery (sham). we extended these studies to adult male prairie voles, microtus ochrogaster, and substantially increased the duration of the tests. during the initial interactions with females, vnx males spent significantly less time with their noses in close proximity to the ...19948055257
estrogen receptor immunoreactivity in specific brain areas of the prairie vole (microtus ochrogaster) is altered by sexual receptivity and genetic sex.the prairie vole is a small rodent with an unusual reproductive strategy. a sexually naive female vole requires male contact to initiate the maturation of her reproductive functions. contact with an unfamiliar adult male vole increases blood estrogen levels, reproductive tissue weights, and brain nuclear estrogen receptor binding levels of female voles. what is not known is: 1) what is the precise distribution of estrogen receptor containing neurons in the prairie vole brain? 2) does male induce ...19947517750
role of septal vasopressin innervation in paternal behavior in prairie voles (microtus ochrogaster).after being paired with females, male prairie voles show major changes in their social behaviors among which is an increase in paternal responsiveness. these changes are accompanied by fluctuations in the density of the [arg8]vasopressin-immunoreactive (avp-ir) fibers in the lateral septum, suggesting that septal avp might be involved in these changes. to explore a possible involvement of septal avp in paternal responsiveness, we tested whether injections of saline, avp, or the v1a receptor anta ...19948278401
testosterone effects on paternal behavior and vasopressin immunoreactive projections in prairie voles (microtus ochrogaster).castration reduced paternal responsiveness of male prairie voles (microtus ochrogaster). castration also reduced the number of vasopressin immunoreactive (avp-ir) cells in the bed nucleus of the stria terminalis (bst) and medial amygdaloid nucleus (ma), as well as the density of avp-ir fibers in the lateral septum. testosterone treatment of castrated voles prevented these changes. the similarities in the effects of the hormonal manipulations on paternal responsiveness and avp immunoreactivity pr ...19938298988
a role for central vasopressin in pair bonding in monogamous prairie voles.monogamous social organization is characterized by selective affiliation with a partner, high levels of paternal behaviour and, in many species, intense aggression towards strangers for defence of territory, nest and mate. although much has been written about the evolutionary causes of monogamy, little is known about the proximate mechanisms for pair bonding in monogamous mammals. the prairie vole, microtus ochrogaster, is a monogamous, biparental rodent which exhibits long-term pair bonds chara ...19938413608
the effects of chronic tannic acid intake on prairie vole (microtus ochrogaster) reproduction.the hypothesis was tested that the reproductive performance of voles would be reduced when fed diets containing tannins either because of increased metabolic rates, decreased intake, or decreased digestive efficiency. we fed a ration containing 4% tannic acid (ta) (dry mass basis) to 24 pair of prairie voles (microtus ochrogaster) and compared reproductive performance (litter size, birth weights, body mass of the young until weaning, and mass changes in the dams) to that of 24 pair of prairie vo ...199324249184
reproductive activation of virgin female prairie voles (microtus ochrogaster) by paired and unpaired males.virgin female microtus ochrogaster were exposed to paired and unpaired unfamiliar adult males in semi-natural arenas. although females were reproductively activated by both types of males, more than twice as many were activated by unpaired (51.6%) as by paired (18.2%) males. our results suggest that, in natural populations of prairie voles, the proportion of philopatric females becoming reproductive is related to the abundance of unpaired males within the population.199324895934
monogamy and the prairie vole. 19938516669
acetate, butyrate and proline uptake in the caecum and colon of prairie voles (microtus ochrogaster).we have measured unidirectional uptake (not transmural flux) of acetate, butyrate and proline by everted sleeves of intact tissue from the jejunum, caecum, proximal colon and distal colon of prairie voles (microtus ochrogaster). there was active (i.e. na(+)-dependent) transport of l-proline in the jejunum, but we found no evidence for it in any region of the hindgut (i.e. the caecum, proximal colon and distal colon). uptake of acetate was carrier-mediated in all three regions of the hindgut, but ...19938478602
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 ...19938280911
olfactory bulb removal affects partner preference development and estrus induction in female prairie voles.in female prairie voles (microtus ochrogaster) bilateral olfactory bulbectomy reduced affiliative behavior, as measured by social contact, and prevented the formation of partner preferences. unilateral olfactory bulb removal did not significantly influence affiliative behavior, but did inhibit partner preferences. bilateral, but not unilateral, bulbectomy significantly reduced the proportion of females exhibiting behavioral estrus following male exposure. in contrast to affiliative and sexual be ...19921409933
development of partner preferences in female prairie voles (microtus ochrogaster): the role of social and sexual experience.prairie voles (microtus ochrogaster) exhibit a monogamous mating system characterized by long-term pair bonds between mates. the purpose of this study was to examine the effect of cohabitation time and sexual experience on the development of pair bond formation in female prairie voles. females that were allowed to cohabit for 24 hr or more, with or without mating, exhibited a strong social preference for a familiar partner versus a strange male. females that cohabited and mated for 6 hr showed s ...19921398553
partner preference development in female prairie voles is facilitated by mating or the central infusion of oxytocin.results of these experiments indicate that females given at least 24 hours of cohabitation with a male develop a social preference for the familiar partner versus a stranger. mating is not essential for the development of partner preferences, but clearly facilitates the onset of preferences. females given six hours of cohabitation showed partner preferences only if they mated with the partner during cohabitation (experiment 2) or if they received oxytocin (experiment 3). females that continued t ...19921626857
oxytocin and social bonding.the prairie vole is an excellent model for examining the neurobiology of social attachment, and in particular of pair-bond formation. in female prairie voles either sexual interactions or oxytocin infusions can hasten the formation of a partner preference. these results implicate oxytocin in the formation of adult heterosexual social bonds. in conjunction with work on other social systems described in this volume, these findings also support the suggestions of klopfer and newton that oxytocin ma ...19921626829
maternal diet influences reproductive development in male prairie vole offspring.the plant compound, 6-methoxy-2-benzoxazolinone (6-mboa), is found in the meristematic tissue of young, vegetatively growing grasses, and its ingestion stimulates the reproductive system of rodents in both short and long photoperiods. the present study demonstrates the existence of a novel mechanism whereby the presence of 6-mboa in the diet of pregnant prairie voles (microtus ochrogaster) enhances gonadal development in their male offspring. female voles were fed specially milled food in which ...19911805270
activation of reproduction in nulliparous and primiparous voles is blocked by vomeronasal organ removal.chemical cues from male voles activate reproduction in female prairie voles (microtus ochrogaster). twelve hours of contact with a male, followed by exposure to his soiled bedding for 2 days, is sufficient to initiate follicular maturation and induce uterine hypertrophy. our recent work indicates that the chemosensory vomeronasal organ (vno) can mediate this response. here, we examined whether other sensory systems can acquire the ability to activate female reproduction as a result of learning o ...19911751636
age of pairing affects reproduction in prairie voles.the effect of the age at pairing on reproduction of weanling prairie voles was studied. the proportion of pairs producing a litter within 60 days was influenced significantly by the age at pairing. more voles paired at 31 days of age produced litters than those paired at 21 days of age. assuming a gestation interval of 21 days, the earliest mating occurred around 33 days of age in both groups. on average, successful matings did not occur until voles were housed together for 2 to 3 weeks. no othe ...19911921321
oxytocin inhibits male sexual behavior in prairie voles.intracerebroventricular (icv) injection of oxytocin (300 ng) produced an immediate cessation in sexual behavior in sexually active male prairie voles (microtus ochrogaster). other social behaviors including social contact, aggression, and autogrooming were not significantly affected by oxytocin, but males that received oxytocin icv, versus injections that missed the ventricles, showed more sleep postures. sexual behavior remained inhibited for at least 24 hours and was not activated in tests wit ...19911924508
effects of photoperiod and 6-methoxy-2-benzoxazolinone on male-induced estrus in prairie voles.prairie voles (microtus ochrogaster) are characterized as facultative breeders with higher rates of reproductive activities observed during spring and summer than autumn and winter. the environmental factors regulating seasonal breeding in this species remain unspecified. short day lengths inhibit reproductive organ development in male prairie voles in the laboratory, but these males remain fertile and capable of siring offspring; female prairie voles have been reported to be reproductively unre ...19912017478
female-female interactions and social stress in prairie voles.trios of prairie voles (microtus ochrogaster) composed of either two estrous sibling or nonsibling females and one male were monitored via time-lapse videotaping over 72 hr. social and sexual behaviors were analyzed as a function of trio type (sibling or nonsibling) and fate (survivor or nonsurvivor) across 12-h time blocks. within nonsibling trios, females that were able to maintain prolonged physical contact with the male within the first 3 days of trio formation later survived and successfull ...19911996946
effects of small mammal and invertebrate herbivory on plant species richness and abundance in tallgrass prairie.a factorial field experiment was designed to test the effects of small mammals and above- and below-ground invertebrates on plant species richness and composition in native tallgrass prairie at konza prairie research natural area, northeast kansas. over a 4-year period, microtus ochrogaster densities were maintained by live-trapping in fenced plots, and invertebrate levels were reduced using the pesticides carbaryl for above-ground invertebrates and an organophosphate (isofenphos) for belowgroun ...199028312749
central and peripheral effects of oxytocin administration in prairie voles (microtus ochrogaster).the present study examined the hypothesis that oxytocin (ot) may influence female sexual behavior in prairie voles (microtus ochrogaster). the effectiveness of ot to induce sexual behavior was tested in ovariectomized females that were injected daily with estradiol benzoate (eb, 0.02 micrograms, twice), a dose insufficient for estrus induction. on the third day females received intracerebroventricular (icv) injections of ot (1, 300, or 1000 ng) or saline vehicle. in the presence of minimal estro ...19902263668
effects of experience and motivation on symmetrical-maze performance in the prairie vole (microtus ochrogaster).sex differences in spatial skills are sometimes attributed to sex differences in spatial experience. this hypothesis rests on two assumptions: spatial experience typically differs with sex and spatial experience has lasting effects on spatial cognition. we tested the latter assumption in a controlled experiment with wild-caught prairie voles (microtus ochrogaster) and their spatially deprived, laboratory-reared, first-generation offspring; we found the assumption to be unjustified. although majo ...19902194739
sex differences in spatial ability and activity in two vole species (microtus ochrogaster and m. pennsylvanicus).the hypothesis that sex differences in maze learning result from sex differences in activity was tested with wild-caught prairie (microtus ochrogaster) and meadow (m. pennsylvanicus) voles. for 38 voles error production and activity were simultaneously measured in a series of 7 symmetrical mazes. repeated-measures analyses of variance (anovas) examined species, sex, maze, and interaction effects for 3 dependent variables: errors, activity, and errors/activity. the pattern of significant effects ...19902191835
simulated drought influences reproduction in male prairie voles.the environmental factors that arrest breeding in prairie voles during the middle of the breeding season are unknown. the role of water availability on reproductive function was examined by limiting water intake to 50% of ad lib water consumption for 10 weeks. at autopsy, testicular, epididymal and seminal vesicle masses were reduced in water restricted males as compared to animals with ad lib access to water. body mass was also reduced in water restricted males. plasma testosterone levels and t ...19892697880
effects of temperature and infection with eimeria ochrogasteri on digestive organs of the prairie vole, microtus ochrogaster.prairie voles, microtus ochrogaster, were infected with eimeria ochrogasteri and exposed to 2 environmental temperatures, 5 and 22 c. dry weights of the small and large intestines increased by 33% and 19%, respectively, in infected animals. infected animals also exhibited a 14% decrease in cecal length compared to uninfected animals. the interaction between temperature and infection affected the length of the small intestine. infected animals maintained at 5 c had longer small intestines than bo ...19892668491
photoperiod and temperature affect reproductive and nonreproductive functions in male prairie voles (microtus ochrogaster).adult male prairie voles (microtus ochrogaster) were housed for 10 wk and exposed to long (16l:8d) or short (8l:16d) photoperiods at 21 degrees or 5 degrees c. maintenance in short day lengths reduced testicular, epididymal, and seminal vesicle mass and also significantly depressed spermatogenic activity. cold ambient temperature further suppressed gonadal size in voles exposed to short days. several pelage characteristics were affected by photoperiod, but not by temperature. increased fur densi ...19892667648
social stimuli augment estrogen receptor binding in preoptic area of female prairie voles.in female prairie voles ovarian estrogen secretion is stimulated by exposure to males. the present study determined that social stimuli can also enhance the neural response to estrogen. ovariectomized female voles given a fixed amount of estradiol and exposed to males had higher levels of estrogen receptor binding in cell nuclei in the preoptic area than did females given estrogen and not exposed to males.19892649206
sexual activity and satiety over an extended observation period in prairie voles (microtus ochrogaster).this study was designed to delineate the course of sexual satiation in prairie voles (microtus ochrogaster). fourteen male-female pairs were allowed to copulate freely for 24 hr under continuous observation. copulations occurred predominantly during the first few hours and decreased in frequency thereafter. the mean number of ejaculations per pair was 5.6 (range, 2-9). two thirds of the ejaculations occurred during the first 3 hr, and over 90% took place within the first 7 hr after the first int ...19883063428
influence of male gonadal hormones and familiarity on pregnancy interruption in prairie voles.pregnancy interruption (pi) was examined in female prairie voles, microtus ochrogaster, exposed to stimuli from males 7 to 12 days after pairing. urine from unfamiliar males interrupted pregnancy when placed directly on the external nares of newly mated females, but urine from familiar stud males was without effect. castration of males did not reduce the efficacy of unfamiliar male urine in interrupting pregnancy. the neuroendocrine system of female prairie voles responded selectively to male ur ...19883061485
multiple exposures to adult males and reproductive activation of virgin female microtus ochrogaster.virgin female microtus ochrogaster living in family groups were reproductively activated by twelve 1-hr exposures over a 3-day period to unrelated sexually experienced males. reproductive activation among virgin females receiving six or eight exposures over a 2- or 3-day period did not differ significantly from that of unexposed control females. thus, frequent multiple exposures to unfamiliar males (and repeated stimulation by a male urinary chemosignal) can override the reproductive suppression ...198824896910
demography of the western harvest mouse, reithrodontomys megalotis, in eastern kansas.reithrodontomys megalotis was live-trapped on three open field grids in eastern kansas from august 1979 to august 1982. one grid was a control on which normal demography was monitored, and two were experimental grids where periodic removal of residents allowed the investigation of the demographic and fitness consequences of emigration. popullations on the control grid showed an annual cycle in numbers, reaching peaks in density during the winter of each year, falling to low densities during the ...198828312689
ultrasonic vocalizations by adult prairie voles, microtus ochrogaster.male and female microtus ochrogaster were presented with anesthetized and awake conspecifics while ultrasonic vocalizations (usvs) were monitored. males produced significantly more usvs than females during 5-min testing sessions. males tended to produce more usvs to unfamiliar females than to familiar female siblings. sexual experience led to increased usv scores by males. these results suggest that usvs by male prairie voles communicate to females the male's gender and his availability for repr ...19883280341
effects of experience and available cues on estrous versus diestrous preferences in male prairie voles, microtus ochrogaster.male prairie vole preferences for estrous versus diestrous females and associated stimuli were investigated. the role of sexual experience in engendering preferences proved more complex than reported for other species. naive males did not display preferences. neither males receiving sexual experience through monogamous cohabitation, nor males housed with two females displayed preferences. males exposed to both estrous and diestrous females, and males housed with other males and females in a semi ...19883290915
effects of hormonal, sexual, and social history on mating and pair bonding in prairie voles.the interactive effects of hormones, sexual history and cohabitation on sexual and social behaviors were examined in pairs of ovariectomized female and sexually experienced male prairie voles (microtus ochrogaster). monitoring with time lapse video tape revealed that females in estradiol benzoate (eb)-induced estrus, and their male partners engaged in high levels of sexual activity which continued intermittently for at least 3 days (until observations were arbitrarily terminated). in conjunction ...19883074309
the influences of conspecific and heterospecific residents on colonization.to determine if dispersing prairie voles, microtus ochrogaster, are prevented from establishing home ranges in habitat already occupied by conspecifics or potentially competitive species, voles were introduced into enclosed populations of: the same species; southern bog lemmings, synaptomys cooperi; cotton rats, sigmodon hispidus; or an empty enclosure. the results indicated that colonization by dispersing voles was negatively affected by resident conspecifics. introduced females were more stron ...198729357185
male stimuli are necessary for female sexual behavior and uterine growth in prairie voles (microtus ochrogaster).in reproductively naive female prairie voles (microtus ochrogaster) direct contact with male urine or housing in a male-soiled cage, in the absence of physical contact, resulted in increased uterine weights, but did not reliably elicit behavioral estrus (defined by lordosis). physical contact with an unfamiliar male, for 1 hr or more, followed by 30 or 48 hr of continuous access to a male-soiled cage, induced lordosis in approximately two-thirds of the females tested. when females were physicall ...19873549517
estrogen and the induction of lordosis in female and male prairie voles (microtus ochrogaster).estrogen elicited lordosis in ovariectomized female prairie voles (microtus ochrogaster). treatment with estradiol benzoate (eb) was particularly effective if administered as multiple injections. very high dose levels were not, in general, any more effective than lower doses. individual animals typically showed lordosis within 24 to 48 hr following the onset of eb treatment and prolonged treatments did not increase the percentage of females responding to eb. castrated male prairie voles did not ...19873549516
males increase serum estrogen and estrogen receptor binding in brain of female voles.sexual development of female prairie voles does not occur unless females are exposed to stimuli from an unfamiliar male. three experiments were conducted to determine whether a saturable high-affinity estradiol binding site (ern) is present in cell nuclei of brain tissue from females exposed to male stimuli and whether serum estradiol and brain ern are correlated with the duration of male exposure. brain ern were detected and found to be correlated with serum estradiol levels. significant increa ...19873554283
removal of the vomeronasal organ disrupts the activation of reproduction in female voles.the reproductive system of female prairie voles remains quiescent in the absence of stimulation from males; however, chemosignals from males are capable of at least partially activating female reproduction. in other species, the vomeronasal system mediates some of the reproductive responses of females to males. we found that surgical removal of the vomeronasal organ (vnx) from adult female prairie voles impeded reproductive activation in response to pairing with stud males: ovarian and uterine w ...19873310053
lespedeza phenolics and penstemon alkaloids: effects on digestion efficiencies and growth of voles.lespedeza cuneata contains high levels of phenolics and is a common food plant of the meadow vole (microtus pennsylvanicus);penstemon digitalis contains substantial quantities of alkaloids and is a common food plant of meadow voles and prairie voles (m. ochrogaster). we investigated the palatability of these plants and the effects of their secondary compounds on the digestion efficiencies and growth of both species of voles. voles ate very little of either plant when alternative food was present ...198624306910
photoperiod influences reproduction in the prairie vole (microtus ochrogaster).four experiments examined the role of photoperiod in the regulation of seasonal breeding in the prairie vole. adult male voles maintained in short (8l:16d) as compared to long (16l:8d) photoperiods for 10 wk had reduced testicular and seminal vesicle weights, but fertility was not impaired. male prairie voles reared from birth until 35 days of age in short as compared to long photoperiods also had reduced testicular and seminal vesicle weights, as well as diminished fertility. the incidence of p ...19853902106
photoperiodic regulation of reproductive development in male prairie voles: influence of laboratory breeding.two populations of male prairie voles, one derived from an outbred laboratory colony and the second consisting of f1 offspring of wild-trapped voles, were tested for responsiveness to photoperiod. animals were reared from birth until 35 days of age either in 16l:8d or 8l:16d photoperiods. short day lengths did not affect the reproductive apparatus of the laboratory-strain voles; however, offspring of wild-caught voles manifested arrested development of the reproductive system in short photoperio ...19853899205
neuroendocrine responsiveness to oestradiol and male urine in neonatally androgenized prairie voles (microtus ochrogaster).the influence of neonatal androgenization on behavioural receptivity was tested by treating female voles on the 3rd day of life with testosterone propionate or with the oil vehicle. after treatment in adulthood with urine or with oestradiol benzoate, androgenized voles were less likely than normal females to display behavioural oestrus and were more likely to engage in agonistic behaviour in tests with stud males. uteri of androgenized and control females treated with oestradiol benzoate in adul ...19853900382
are transferrin and leucine aminopeptidase electromorphs reliable genetic markers in the prairie vole, microtus ochrogaster?the reliability of tf and lap electromorphs as genetic markers in microtus ochrogaster was examined by taking 18 voles captured in the wild during the summer and subjecting them to winter conditions for one month. during this time voles were bled each week and their plasma scored for tf and lap phenotypes using starch gel electrophoresis. there were no changes in the mobility of the tf and lap electromorphs in the same animal when fresh samples were used for electrophoresis. however, there were ...198528310814
pregnancy interruption in microtus ochrogaster: laboratory artifact or field phenomenon?females of at least 8 species of rodent will terminate pregnancies after exposure to a "strange" male or his odors in the laboratory. although only suggestive evidence exists for the occurrence of pregnancy interruption in the field, this laboratory phenomenon has been assigned important adaptive roles in the reproductive biology of rodents. in the present study, the extent of pregnancy interruption was investigated for prairie voles (microtus ochrogaster) in semi-natural enclosures where contin ...19846380603
plant phenolics as chemical defenses: effects of natural phenolics on survival and growth of prairie voles (microtus ochrogaster).very few studies have shown experimentally that plant chemical defenses actually reduce the performance of individual mammalian herbivores, much less the density of mammalian populations. we investigated the effects of representatives of three classes of plant phenoiics on the survival and growth of prairie voles by incorporating the compounds into artificial diets and feeding them to weanlings for three weeks. at low levels of protein, both quercetin (a flavonoid) and tannic acid (a hydrolyzabl ...198424318492
suppression of reproductive maturation in male-stimulated virgin female microtus by a female urinary chemosignal.urine from female microtus ochrogaster possesses a chemosignal that suppresses reproductive maturation in other females. uterine enlargement in virgin females stimulated by a male was suppressed by subsequent association with another female or by application of female urine on the nose. females so suppressed are not able to achieve estrus. urine from virgin sibling and non-sibling females and from pregnant females possesses the suppressing effect.198324923608
resistance of the prairie vole (microtus ochrogaster) and the woodrat (neotoma floridana), in kansas, to venom of the osage copperhead (agkistrodon contortrix phaeogaster).prairie vole (microtus ochrogaster) serum has no anti-lysing or antibody activity against osage copperhead (agkistrodon contortrix phaeogaster) venom. however, the serum has an anti-hemorrhagic component, which significantly reduces the size of hemorrhage produced by the minimal hemorrhagic dose of venom and which blocks the minimal hemorrhagic dose at a dilution of 1/8. woodrat (neotoma floridana) serum also has an antihemorrhagic component which blocks the minimal hemorrhagic dose at a dilutio ...19826753240
male vole urine changes luteinizing hormone-releasing hormone and norepinephrine in female olfactory bulb.female prairie voles (microtus ochrogaster) exposed to a single drop of male urine on the upper lip showed changes in concentrations of luteinizing hormone-releasing hormone (lhrh) and norepinephrine in olfactory bulb tissue; no such changes occurred in dopamine concentration. the changes were measured in the posterior but not the anterior olfactory bulb tissue of females within 1 hour after they were exposed to urine. these females also showed rapid increases in serum concentrations of luteiniz ...19817010608
phenotypic variation in electromorphs previously considered to be genetic markers in microtus ochrogaster.the allelic frequencies of the plasma enzymes transferrin (tf) and leucine aminopeptidase (lap) have been shown previously to correlate with population density, population growth rate and mortality in microtus ochrogaster. such changes in allozymic frequencies of tf and lap have been used by others as evidence supporting the chitty/krebs genetic-behavioral hypothesis of population growth. in this study, prairie voles were captured in midwinter and in midsummer, and brought to the lab where their ...198128310095
male-related pheromones and the activation of female reproduction in the prairie vole (microtus ochrogaster). 19807008851
temporal patterns of allozymic variation in fluctuating populations of microtus ochrogaster. 197828567928
shifts of thermogenesis in the prairie vole (microtus ochrogaster) : strategies for survival in a seasonal environment.the weight-specific oxygen consumption ([formula: see text]) of prairie voles caught in winter is 24% higher at 27.5° c and 29% higher at 7.5° c than that of summer animals, thus affording a higher weight-specific thermogenesis in winter than in summer which may allow tolerance to lower thermal exposures. coincident with the increase in weight-specific rates of oxygen consumption is a decrease in body weight. when total energetic cost to maintain an animal per unit time is calculated, the cost a ...197728308803
embryonic susceptibility of microtus ochrogaster (common prairie vole) to phenyl mercuric acetate.pregnant m. ochrogaster received single intraperitoneal (i.p.) doses of 0.06, 0.125, 0.25, 0.5, 1,2, or 5 mg phenyl mercuric acetate (pma/kg of body weight on day 8, 9, or 10 of gestation or 0.5 mg pma/kg on day 7, 8, 9, 10, 11, or 12 of gestation. no toxicity was exhibited, and no abnormal fetuses were observed in any group. an embryocidal effect that depended on dose and stage of development was determined by increased numbers of resorption sites; resorption sites were dose-dependent, and the ...2013793090
duration of the cycle of the seminiferous epithelium in the prairie vole (microtus ochrogaster ochrogaster).the cycle of the seminiferous epithelium in m. o. ochrogaster was divided into eight readily recognizable stages based on the morphology of the developing spermatid. the mean relative frequencies of stages i through viii were 11.6, 19.25, 20.00, 19.00, 8.42, 6.17, 9.25 and 6.58%, respectively. the duration of one cycle of the seminiferous epithelium in this species, as determined from autoradiographs of thymidine-h3 injected testes was 7.17 days (s.e. +/- 0.03). this is the shortest spermatogeni ...1976781176
male-induced pregnancy termination in the prairie vole, microtus ochrogaster.postimplantation as well as preimplantation pregnancy in prairie voles can be terminated by replacing the original stud male with an unfamiliar male. the pregnancy is disrupted by the ensuing male-induced estrus. females spontaneously abort their litters, become receptive, and successfully breed again 4 or 5 days after introduction of the new male.19751114340
effects of variations in the male copulatory behavior on ovulation and implantation in prairie voles, microtus ochrogaster.the effects of copulation on ovulation and implantation were studied in the prairie vole (microtus ochrogaster). both 1 and 2 ejaculatory series induced ovulation in 9 of 10 females. 2 ejaculatory series resulted in slightly fewer corpora lutea and implanted embryos, and in a slightly greater incidence in intrauterine mortality. in the first ejaculatory series, the likelihood of ovulation increases with increased numbers of intromissions and ejaculatory thrusts. vaginal penetration is required f ...19744616904
three mutations and the karyotype of the prairie vole. white spotting, polydipsia, and muscular dystrophy in microtus ochrogaster. 20094436536
the effect of weanling and adult males on sexual maturation in female voles (microtus ochrogaster). 19744837804
postnatal development of the prairie vole, microtus ochrogaster. 19734347759
a quantitative description of copulatory behavior in prairie voles (microtus ochrogaster). 19734802024
esterase polymorphisms in microtus ochrogaster: interaction and linkage. 19724199798
experimental analysis of relative fitness in transferrin genotypes of microtus ochrogaster. 197128565029
high population density of microtus ochrogaster. 19715104086
Displaying items 501 - 600 of 685