| effects of exposure to bisphenol a and ethinyl estradiol on the gut microbiota of parents and their offspring in a rodent model. | gut dysbiosis may result in various diseases, such as metabolic and neurobehavioral disorders. exposure to endocrine disrupting chemicals (edcs), including bisphenol a (bpa) and ethinyl estradiol (ee), especially during development, may also increase the risk for such disorders. an unexplored possibility is that edc-exposure might alter the gut microbial composition. gut flora and their products may thus be mediating factors for the disease-causing effects of these chemicals. to examine the effe ... | 2016 | 27624382 |
| social and physical environments as a source of individual variation in the rewarding effects of testosterone in male california mice (peromyscus californicus). | despite extensive research revealing the occurrence of testosterone (t) pulses following social encounters, it is unclear how they lead to varied behavioral responses. we investigated the influence of residency (home versus unfamiliar environment) and social/sexual experience (pair-bonded, isolated or housed with siblings) on the plasticity of t's rewarding effects by measuring the development of conditioned place preferences (cpps), a classical paradigm used to measure the rewarding properties ... | 2016 | 27476433 |
| inhibition of vasopressin v1a receptors in the medioventral bed nucleus of the stria terminalis has sex- and context-specific anxiogenic effects. | vasopressin v1a receptors (v1ar) are thought to contribute to the pathophysiology of psychiatric disorders such as anxiety and depression, sparking interest in v1ar as a therapeutic target. although the global effects of v1ar have been documented, less is known about the specific neural circuits mediating these effects. moreover, few studies have examined context-specific v1ar function in both males and females. by using the california mouse, we first studied the effects of sex and social defeat ... | 2016 | 27452721 |
| consequences of fatherhood in the biparental california mouse (peromyscus californicus): locomotor performance, metabolic rate, and organ masses. | although effects of motherhood on mothers have been well documented in mammals, the effects of fatherhood on fathers are not well known. we evaluated effects of being a father on key metabolic and performance measures in the california mouse, peromyscus californicus. california mice are genetically monogamous in the wild, and fathers show similar parental behavior to mothers, with the exception of lactation. to investigate the impact of fatherhood on fathers, focal males were paired with an inta ... | 2017 | 27082723 |
| neurogenesis and anxiety-like behavior in male california mice during the mate's postpartum period. | our understanding of postpartum anxiety (ppa) in fathers is limited, despite the negative consequences of anxiety on the father and child. offspring contact reduces ppa in mothers; however, parallel investigations in fathers has gone unaddressed. adult neurogenesis in the dentate gyrus (dg) contributes to anxiety regulation and is altered during the postpartum period, yet the effects of fatherhood on the production, or survival, of newborn cells in the dg, and the role of adult neurogenesis in p ... | 2016 | 26750200 |
| effects of social defeat on dopamine neurons in the ventral tegmental area in male and female california mice. | dopamine neurons in the ventral tegmental area (vta) have important functions related to rewards but are also activated in aversive contexts. electrophysiology studies suggest that the degree to which vta dopamine neurons respond to noxious stimuli is topographically organized across the dorsal-ventral extent. we used c-fos immunohistochemistry to examine the responses of vta dopamine neurons in contexts of social defeat and social approach. studying monogamous california mice (peromyscus califo ... | 2015 | 26469289 |
| sex-dependent effects of developmental exposure to bisphenol a and ethinyl estradiol on metabolic parameters and voluntary physical activity. | endocrine disrupting chemicals (edc) have received considerable attention as potential obesogens. past studies examining obesogenic potential of one widespread edc, bisphenol a (bpa), have generally focused on metabolic and adipose tissue effects. however, physical inactivity has been proposed to be a leading cause of obesity. a paucity of studies has considered whether edc, including bpa, affects this behavior. to test whether early exposure to bpa and ethinyl estradiol (ee, estrogen present in ... | 2015 | 26378919 |
| 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 stress-induced social withdrawal: independence from adult gonadal hormones and inhibition of female phenotype by corncob bedding. | there is compelling evidence for important sex differences in behavioral and hormonal responses to psychosocial stress. here we examined the effects of gonadal hormones on behavioral responses to social defeat stress in monogamous california mice (peromyscus californicus). three episodes of social defeat induced social withdrawal in intact females but not males. gonadectomy blocked corticosterone responses to defeat in females and sensitized male corticosterone responses. however, gonadectomy ha ... | 2013 | 23384773 |
| paternal retrievals increase testosterone levels in both male and female california mouse (peromyscus californicus) offspring. | the importance of maternal care on offspring development has received considerable attention, although more recently, researchers have begun to focus on the significance of paternal contributions. in the monogamous and bi-parental california mouse, fathers provide high levels of care, and therefore serve as a model system for studying paternal effects on behavior and underlying neuroendocrine mechanisms. paternal retrievals in this species influence long term changes in brain (expression of argi ... | 2015 | 26065732 |
| effects of social defeat on paternal behavior and pair bonding behavior in male california mice (peromyscus californicus). | male parental care is an important social behavior for several mammalian species. psychosocial stress is usually found to inhibit maternal behavior, but effects on paternal behavior have been less consistent. we tested the effects of social defeat stress on pair bond formation and paternal behavior in the monogamous california mouse (peromyscus californicus). social defeat reduced time spent in a chamber with a stranger female during a partner preference test conducted 24h after pairing, but inc ... | 2018 | 29289657 |
| sexual dimorphism in the brain of the monogamous california mouse (peromyscus californicus). | sex differences in behavior and morphology are usually assumed to be stronger in polygynous species compared to monogamous species. a few brain structures have been identified as sexually dimorphic in polygynous rodent species, but it is less clear whether these differences persist in monogamous species. california mice are among the 5% or less of mammals that are considered to be monogamous and as such provide an ideal model to examine sexual dimorphism in neuroanatomy. in the present study we ... | 2013 | 23881046 |
| social isolation increases cell proliferation in male and cell survival in female california mice (peromyscus californicus). | social environment has direct effects on an animal's behavior, physiology and neurobiology. in particular, adult neurogenesis is notably affected by a variety of social manipulations, including social isolation. we hypothesized that social isolation should have particularly acute effects on neurogenesis in a highly social (monogamous and bi-parental) species such as peromyscus californicus, the california mouse. adult male and female p. californicus mice were housed in isolation or in same-sex p ... | 2015 | 26342752 |
| paternal responsiveness is associated with, but not mediated by reduced neophobia in male california mice (peromyscus californicus). | hormones associated with pregnancy and parturition have been implicated in facilitating the onset of maternal behavior via reductions in neophobia, anxiety, and stress responsiveness. to determine whether the onset of paternal behavior has similar associations in biparental male california mice (peromyscus californicus), we compared paternal responsiveness, neophobia (novel-object test), and anxiety-like behavior (elevated plus maze, epm) in isolated virgins (housed alone), paired virgins (house ... | 2012 | 22634280 |
| a comparison of scent marking between a monogamous and promiscuous species of peromyscus: pair bonded males do not advertise to novel females. | scent marking can provide behavioral and physiological information including territory ownership and mate advertisement. it is unknown how mating status and pair cohabitation influence marking by males from different social systems. we compared the highly territorial and monogamous california mouse (peromyscus californicus) to the less territorial and promiscuous white-footed mouse (p. leucopus). single and mated males of both species were assigned to one of the following arenas lined with filte ... | 2012 | 22393377 |
| in three brain regions central to maternal behaviour, neither male nor female phodopus dwarf hamsters show changes in oestrogen receptor alpha distribution with mating or parenthood. | oestrogen receptor (er)alpha immunoreactivity in three brain regions relevant to maternal behaviour (medial preoptic area, bed nucleus of the stria terminalis and medial amygdala) was measured in two species of dwarf hamster that both mate during a postpartum oestrous but differ in expression of paternal behaviour. male and female phodopus campbelli and phodopus sungorus were sampled as sexually naive adults, following mating to satiety, and as new parents. in all brain regions, females expresse ... | 2008 | 19094078 |
| opposing hormonal mechanisms of aggression revealed through short-lived testosterone manipulations and multiple winning experiences. | territorial aggression is influenced by many social and environmental factors. since aggression is a costly behavior, individuals should account for multiple factors such as population density or reproductive status before engaging in aggression. previous work has shown that male california mice (peromyscus californicus) respond to winning aggressive encounters by initiating aggression more quickly in future encounters, and we investigated the physiological basis for this effect. we found that i ... | 2004 | 15019798 |
| disruption of parenting behaviors in california mice, a monogamous rodent species, by endocrine disrupting chemicals. | the nature and extent of care received by an infant can affect social, emotional and cognitive development, features that endure into adulthood. here we employed the monogamous, california mouse (peromyscus californicus), a species, like the human, where both parents invest in offspring care, to determine whether early exposure to endocrine disrupting chemicals (edc: bisphenol a, bpa; ethinyl estradiol, ee) of one or both parents altered their behaviors towards their pups. females exposed to eit ... | 2015 | 26039462 |
| effects of parental status on male body mass in the monogamous, biparental california mouse. | studies of biparental mammals demonstrate that males may undergo systematic changes in body mass as a consequence of changes in reproductive status; however, these studies typically have not teased apart effects of specific social and reproductive factors, such as cohabitation with a female per se, cohabitation with a breeding female specifically, and engagement in paternal care. we aimed to determine whether california mouse (peromyscus californicus) fathers undergo systematic changes in body m ... | 2015 | 26005292 |
| ultrasonic vocalizations and ontogenetic development in california mice (peromyscus californicus). | this experiment investigated the time-course of behavioral and physical development in 18 male and 18 female pups from 18 litters of california mice. from 1 to 23 days of age animals were observed for a 6-min observation period every other day, followed by a neurobehavioral testing session. ultrasonic vocalizations (uvs), coordinated movements, neuromotor indicators and physical parameters were measured. the production of uvs peaked during the first week of development, remained stable from 9 to ... | 2002 | 12270517 |
| 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 |
| postcontest blockade of dopamine receptors inhibits development of the winner effect in the california mouse (peromyscus californicus). | the winner effect is an accumulation of previous wins that increase future winning. a primary unanswered question about the winner effect is how do individuals integrate information about previous wins? dopamine (da) has been implicated because phosphorylated tyrosine hydroxylase (pth), the rate-limiting enzyme for da biosynthesis, is elevated following multiple winning experiences. moreover, da receptor blockers and agonists influence aggression when administered prior to male-male contests. in ... | 2015 | 25798633 |
| male fidelity expressed through rapid testosterone suppression of ultrasonic vocalizations to novel females in the monogamous california mouse. | the steroid hormone testosterone (t) is a well-known mediator of male sexual behavior in vertebrates. however, less is known about t's rapid effects on sexual behavior, particularly those involving ultrasonic vocalizations (usvs), a mode of communication that can influence mate acquisition in rodents. using the monogamous california mouse, peromyscus californicus, we tested whether t rapidly alters male usv production by giving t or saline injections to non-paired (sexually naïve) males and pair ... | 2015 | 25725427 |
| unusual patterns of susceptibility to degradation of dna isolated from tissues in peromyscus californicus. | isolation of intact, high molecular weight genomic dna from the livers of 2 subspecies of peromyscus californicus without excessive degradation was typically unattainable, whereas highly intact dna from livers of other peromyscus (field mice) species is invariably obtained using the same isolation methods. additionally, highly intact dna was obtained from splenic tissues of adult p. californicus and hepatic tissue of juvenile animals, indicating that the phenomenon is tissue-specific and age-rel ... | 1993 | 8366674 |
| 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 |
| contributions of paternal care to the growth and development of the young in peromyscus californicus. | | 1974 | 4847518 |
| copulatory behavior of california mice (peromyscus californicus). | | 1974 | 4412636 |
| effects of reproductive experience on central expression of progesterone, oestrogen α, oxytocin and vasopressin receptor mrna in male california mice (peromyscus californicus). | fatherhood in biparental mammals is accompanied by distinct neuroendocrine changes in males, involving some of the same hormones involved in maternal care. in the monogamous, biparental california mouse (peromyscus californicus), paternal care has been linked to changes in the central and/or peripheral availability of oestrogen, progesterone, vasopressin and oxytocin, although it is not known whether these endocrine fluctuations are associated with changes in receptor availability in the brain. ... | 2015 | 25659593 |
| detection and evaluation of antibody response to a baylisascaris-specific antigen in rodent hosts with the use of western blotting and elisa. | diagnosis of parasitic diseases that involve tissue-stage larvae is challenging, and serology remains the most effective antemortem test for detecting these infections. baylisascaris procyonis, the raccoon roundworm, is a zoonotic ascarid. raccoons are the usual definitive host, and humans may be infected as accidental hosts. more than 150 species of birds and mammals may act as paratenic hosts, and rodents play an important role in the transmission and maintenance of this parasite in nature. mi ... | 2018 | 30074878 |
| effects of defeat stress on behavioral flexibility in males and females: modulation by the mu-opioid receptor. | behavioral flexibility is a component of executive functioning that allows individuals to adapt to changing environmental conditions. independent lines of research indicate that the mu opioid receptor (mor) is an important mediator of behavioral flexibility and responses to psychosocial stress. the current study bridges these two lines of research and tests the extent to which social defeat and mor affect behavioral flexibility and whether sex moderates these effects in california mice (peromysc ... | 2015 | 25615538 |
| variation in the density of oxytocin receptors in the brain as mechanism of adaptation to specific social and reproductive strategies. | most species have predominant forms of social and reproductive behavior driven by many years of selection pressures and evolution. for example, rodent species can live in small or large groups, behave more tolerant or aggressively toward conspecifics (including newborns), and form or not bonds with other members of the group (including sexual partners). any of those behavioral adaptations could result in good fitness for the species, but could also require compromises such as sharing resources, ... | 2020 | 31734142 |
| hypothalamic vasopressin systems are more sensitive to the long term effects of social defeat in males versus females. | vasopressin signaling has important effects on the regulation of social behaviors and stress responses, and is considered a promising pathway to target for new therapeutics of stress-induced psychiatric disorders. although there is evidence for sex differences in the behavioral effects of arginine vasopressin (avp), few data have directly compared the effects of stress on endogenous avp signaling in males and females. we used california mice (peromyscus californicus) to study the short and long ... | 2015 | 25306217 |
| the effects of exogenous melatonin and melatonin receptor blockade on aggression and estrogen-dependent gene expression in male california mice (peromyscus californicus). | photoperiodic regulation of aggression has been well established in several vertebrate species, with rodents demonstrating increased aggression in short day photoperiods as compared to long day photoperiods. previous work suggests that estrogens regulate aggression via rapid nongenomic pathways in short days and act more slowly in long days, most likely via genomic pathways. the current study therefore examines the role of melatonin in mediating aggression and estrogen-dependent gene transcripti ... | 2014 | 24518867 |
| effects of kappa opioid receptors on conditioned place aversion and social interaction in males and females. | the effects of kappa opioid receptors (kor) on motivated behavior are well established based on studies in male rodents, but relatively little is known about the effects of kor in females. we examined the effects of kor activation on conditioned place aversion and social interaction in the california mouse (peromyscus californicus). important differences were observed in long-term (place aversion) and short-term (social interaction) effects. females but not males treated with a 2.5 mg/kg dose of ... | 2014 | 24445073 |
| sex differences in stress-induced social withdrawal: role of brain derived neurotrophic factor in the bed nucleus of the stria terminalis. | depression and anxiety disorders are more common in women than men, and little is known about the neurobiological mechanisms that contribute to this disparity. recent data suggest that stress-induced changes in neurotrophins have opposing effects on behavior by acting in different brain networks. social defeat has been an important approach for understanding neurotrophin action, but low female aggression levels in rats and mice have limited the application of these methods primarily to males. we ... | 2013 | 24409132 |
| father absence in the monogamous california mouse impairs social behavior and modifies dopamine and glutamate synapses in the medial prefrontal cortex. | the role of the father in psycho-affective development is indispensable. yet, the neurobehavioral effects of paternal deprivation (pd) are poorly understood. here, we examined the behavioral consequences of pd in the california mouse, a species displaying monogamous bonding and biparental care, and assessed its impact on dopamine (da), serotonin (5-ht), and glutamate (glu) transmission in the medial prefrontal cortex (mpfc). in adult males, deficits in social interaction were observed, when a fa ... | 2015 | 24304503 |
| chronic variable stress in fathers alters paternal and social behavior but not pup development in the biparental california mouse (peromyscus californicus). | stress and chronically elevated glucocorticoid levels have been shown to disrupt parental behavior in mothers; however, almost no studies have investigated corresponding effects in fathers. the present experiment tested the hypothesis that chronic variable stress inhibits paternal behavior and consequently alters pup development in the monogamous, biparental california mouse (peromyscus californicus). first-time fathers were assigned to one of three experimental groups: chronic variable stress ( ... | 2013 | 24157379 |
| sex differences in effects of dopamine d1 receptors on social withdrawal. | dopamine signaling in the nucleus accumbens (nac) plays a critical role in the regulation of motivational states. recent studies in male rodents show that social defeat stress increases the activity of ventral tegmental dopamine neurons projecting to the nac, and that this increased activity is necessary for stress-induced social withdrawal. domestic female mice are not similarly aggressive, which has hindered complementary studies in females. using the monogamous california mouse (peromyscus ca ... | 2014 | 24120838 |
| differences in placentophagia in relation to reproductive status in the california mouse (peromyscus californicus). | parturient females ingest placenta in most mammalian species, whereas fathers may do so in species in which both parents provide care for their offspring. to determine if the propensity to eat placenta varies with reproductive status in the biparental california mouse, we presented placenta to virgin (housed with a same-sex pairmate), expectant (pregnant with their first litter), and multiparous adult males and females. liver was presented identically, 3-7 days later, as a control. multiparous f ... | 2014 | 24114333 |
| interactions between parents and parents and pups in the monogamous california mouse (peromyscus californicus). | the california mouse (peromyscuscalifornicus) may be a valuable animal model to study parenting as it is one of the few monogamous and biparental rodent species. by using automated infra-red imaging and video documentation of established pairs spanning two days prior to birth of the litter until d 5 of post natal development (pnd), it was possible to follow interactions between parents and between parents and pups. the paired males were attentive to their partners in the form of grooming and sni ... | 2013 | 24069441 |
| non-genomic transmission of paternal behaviour between fathers and sons in the monogamous and biparental california mouse. | maternal behaviour has profound, long-lasting implications for the health and well-being of developing offspring. in the monogamous california mouse (peromyscus californicus), care by both parents is critical for offspring survival. we tested the hypothesis that similar to maternal care in rodents, paternal huddling and grooming (hg) behaviour can be transmitted to future generations via behavioural mechanisms. in california mice, testosterone maintains paternal hg behaviour. in the present stud ... | 2013 | 23698012 |
| physiological and neuroendocrine responses to chronic variable stress in male california mice (peromyscus californicus): influence of social environment and paternal state. | social environment and parental state affect stress responses in mammals, but their impact may depend on the social and reproductive strategy of the species. the influences of cohabitation with a male or female conspecific, and the birth of offspring, on the physiological and endocrine responses to chronic variable stress were studied in the monogamous and biparental california mouse (peromyscus californicus). adult male california mice were housed either with a male cage mate (virgin males, vm) ... | 2013 | 23582312 |
| effect of reproductive status on hypothalamic-pituitary-adrenal (hpa) activity and reactivity in male california mice (peromyscus californicus). | previous studies indicate that reproductive condition can alter stress response and glucocorticoid release. although the functional significance of hypothalamic-pituitary-adrenal (hpa) axis modulation by breeding condition is not fully understood, one possible explanation is the behavior hypothesis, which states that an animal's need to express parental behavior may be driving modulation of the hpa axis. this possibility is consistent with findings of blunted activity and reactivity of the hpa a ... | 2013 | 23474132 |
| effects of aging on hypothalamic-pituitary-adrenal (hpa) axis activity and reactivity in virgin male and female california mice (peromyscus californicus). | life history theory posits that organisms face a trade-off between current and future reproductive attempts. the physiological mechanisms mediating such trade-offs are still largely unknown, but glucocorticoid hormones are likely candidates as elevated, post-stress glucocorticoid levels have been shown to suppress both reproductive physiology and reproductive behavior. aged individuals have a decreasing window in which to reproduce, and are thus predicted to invest more heavily in current as opp ... | 2013 | 23458287 |
| individual variation in paternal responses of virgin male california mice (peromyscus californicus): behavioral and physiological correlates. | california mice peromyscus californicus are a rodent species in which fathers provide extensive paternal care; however, behavioral responses of virgin males toward conspecific neonates vary from paternal behavior to tolerance to infanticide. indirect evidence suggests that paternal responses might be influenced by social status potentially through increased stress and anxiety in subordinate males. to test this hypothesis, we housed 12 virgin male california mice in same-sex dyads on weaning and ... | 2016 | 23099470 |
| glucocorticoids, aerobic physiology, and locomotor behavior in california mice. | the glucocorticoid hormones corticosterone (cort) and cortisol influence numerous physiological, morphological, and behavioral functions. however, few studies have addressed possible relationships between individual differences in glucocorticoid concentrations and whole-animal performance or metabolism. because cort is important in glucose regulation and energy metabolism and can influence activity levels, we hypothesized that individual variation in baseline circulating cort levels would correl ... | 2016 | 23099464 |
| hypothalamic-pituitary-adrenal (hpa) axis function in the california mouse (peromyscus californicus): changes in baseline activity, reactivity, and fecal excretion of glucocorticoids across the diurnal cycle. | the california mouse, peromyscus californicus, is an increasingly popular animal model in behavioral, neural, and endocrine studies, but little is known about its baseline hypothalamic-pituitary-adrenal (hpa) axis activity or hpa responses to stressors. we characterized plasma corticosterone (cort) concentrations in p. californicus under baseline conditions across the diurnal cycle, in response to pharmacological manipulation of the hpa axis, and in response to a variety of stressors at differen ... | 2012 | 23026495 |
| is promiscuity associated with enhanced selection on mhc-dqα in mice (genus peromyscus)? | reproductive behavior may play an important role in shaping selection on major histocompatibility complex (mhc) genes. for example, the number of sexual partners that an individual has may affect exposure to sexually transmitted pathogens, with more partners leading to greater exposure and, hence, potentially greater selection for variation at mhc loci. to explore this hypothesis, we examined the strength of selection on exon 2 of the mhc-dqα locus in two species of peromyscus. while the califor ... | 2012 | 22649541 |
| effects of photoperiod and food restriction on the reproductive physiology of female california mice. | many temperate-zone animals use changes in photoperiod to time breeding. shorter term cues, like food availability, are integrated with photoperiod to adjust reproductive timing under unexpected conditions. many mice of the genus peromyscus breed in the summer. california mice (peromyscus californicus), however, can breed year round, but tend to begin breeding in the winter. glial cells may be involved in transduction of environmental signals that regulate gonadotrophin releasing hormone i (gnrh ... | 2012 | 22245263 |
| multigenerational effects of bisphenol a or ethinyl estradiol exposure on f2 california mice (peromyscus californicus) pup vocalizations. | rodent pups use vocalizations to communicate with one or both parents in biparental species, such as california mice (peromyscus californicus). previous studies have shown california mice developmentally exposed to endocrine disrupting chemicals, bisphenol a (bpa) or ethinyl estradiol (ee), demonstrate later compromised parental behaviors. reductions in f1 parental behaviors might also be due to decreased emissions of f2 pup vocalizations. thus, vocalizations of f2 male and female california mic ... | 2018 | 29912934 |
| effects of the presence of the father on pup development in california mice (peromyscus californicus). | pup development and behavior in california mice were studied in litters housed with single mothers, or with fathers and mothers living together. behavior of pups was recorded during a 15-min session every 2 days from 10 to 30 days of age. physical contact, locomotion, grooming, and physical development indicators were recorded. it was found that the physical contact between siblings was greater and there was a tendency to have more contact between pup and either parent in the group in which the ... | 2003 | 12621650 |
| influence of photoperiod, green food, and water availability on reproduction in male california mice (peromyscus californicus). | california mice (peromyscus californicus) breed primarily during the winter rainy season and generally terminate breeding during the dry summer months. this pattern of reproduction could be regulated by day length, availability of green vegetation, or water availability. the effects of photoperiod and green vegetation on reproduction were examined in experiment 1 by housing adult male p. californicus either in long (ld 14:10) or short (ld 8:16) photoperiods for 10 weeks with ad lib food and wate ... | 1995 | 7652040 |
| chemical characterization of urinary volatile compounds ofperomyscus californicus, a monogamous biparental rodent. | the urinary profiles of adult female and male california mice were examined to determine the volatile compounds that may affect reproduction. the urinary volatiles identified by gas chromatography-mass spectrometry (gc-ms) include ketones, pyrazines, alkanes, nitrile, and aldehyde. none of volatile compounds was specific to males or females. the concentration of urinary volatiles in pregnant and lactating females was significantly higher than in virgin females. male urinary volatile concentratio ... | 1994 | 24241826 |
| endocrine disruption of gene expression and microrna profiles in hippocampus and hypothalamus of california mice: association of gene expression changes with behavioural outcomes. | the hypothalamus and hippocampus are sensitive to early exposure to endocrine disrupting chemicals (edcs). two edcs that have raised particular concerns are bisphenol a (bpa), a widely prevalent chemical in many common household items, and genistein (gen), a phyto-oestrogen present in soy and other plants. we hypothesised that early exposure to bpa or gen may lead to permanent effects on gene expression profiles for both coding rnas (mrnas) and micrornas (mirs), which can affect the translation ... | 2020 | 32297422 |
| hypothalamic gene expression changes in f1 california mice (peromyscus californicus) parents developmentally exposed to bisphenol a or ethinyl estradiol. | bisphenol a (bpa) is a pervasive industrial chemical used in many common household items. to examine how early exposure to bpa and ethinyl estradiol (ee, estrogen in birth control pill) might affect biparental care, effects of these chemicals in male and female california mice (peromyscus californicus), who are monogamous and biparental, were examined. california mice exposed during pre- and peri-natal life to bpa at an environmentally relevant concentration or ee show later disrupted biparental ... | 2018 | 30003164 |
| extrahypothalamic oxytocin neurons drive stress-induced social vigilance and avoidance. | oxytocin increases the salience of both positive and negative social contexts and it is thought that these diverse actions on behavior are mediated in part through circuit-specific action. this hypothesis is based primarily on manipulations of oxytocin receptor function, leaving open the question of whether different populations of oxytocin neurons mediate different effects on behavior. here we inhibited oxytocin synthesis in a stress-sensitive population of oxytocin neurons specifically within ... | 2020 | 33020267 |
| mating system is correlated with immunogenetic diversity in sympatric species of peromyscine mice. | the number of reproductive partners per individual varies markedly across animal mating systems. this variation may be an important determinant of patterns of immunogenetic diversity, particularly at major histocompatibility complex (mhc) class i and ii loci. to compare immunogenetic variation in taxa with markedly different mating systems, we used rnaseq-generated data to quantify genotypic diversity in three species of peromyscine rodents: the monogamous california mouse (peromyscus californic ... | 2020 | 32701975 |
| developmental exposure of california mice to endocrine disrupting chemicals and potential effects on the microbiome-gut-brain axis at adulthood. | xenoestrogens are chemicals found in plant products, such as genistein (gen), and in industrial chemicals, e.g., bisphenol a (bpa), present in plastics and other products that are prevalent in the environment. early exposure to such endocrine disrupting chemicals (edc) may affect brain development by directly disrupting neural programming and/or through the microbiome-gut-brain axis. to test this hypothesis, california mice (peromyscus californicus) offspring were exposed through the maternal di ... | 2020 | 32616744 |
| effects of sex and age on parental motivation in adult virgin california mice. | female mammals often demonstrate a rapid initiation of maternal responsiveness immediately after giving birth, as a result of neuroendocrine changes that occur during pregnancy and parturition. however, fathers and virgins of some species may display infant care similar to that performed by mothers but without experiencing these physiological events. in biparental species, in which both mothers and fathers care for their offspring, both sex and age may affect parental motivation, even in adult v ... | 2020 | 32603677 |
| testosterone-related behavioral and neural mechanisms associated with location preferences: a model for territorial establishment. | territoriality is an adaptive behavioral trait that is important for animal's fitness and there still remains much to learn about the proximate mechanisms underlying the development of territoriality. we speculate that the formation of a conditioned place preference (cpp), an increased time allocation to the environment where a rewarding experience occurred, contributes to territoriality. testosterone (t) plays an important role in modulating territorial behaviors and t pulses can induce a cpp. ... | 2020 | 32007517 |
| long-term effects of fatherhood on morphology, energetics, and exercise performance in california mice (peromyscus californicus). | in male mammals that provide care for their offspring, fatherhood can lead to changes in behavioral, morphological, and physiological traits, some of which might constitute trade-offs. however, relatively little is known about these changes, especially across multiple reproductive bouts, which are expected to magnify differences between fathers and nonreproductive males. we evaluated consequences of fatherhood in the monogamous, biparental california mouse (peromsycus californicus) across seven ... | 2020 | 31808736 |
| the challenge hypothesis revisited: focus on reproductive experience and neural mechanisms. | our review focuses on findings from mammals as part of a special issue "30th anniversary of the challenge hypothesis". here we put forth an integration of the mechanisms through which testosterone controls territorial behavior and consider how reproductive experience may alter these mechanisms. the emphasis is placed on the function of socially induced increases in testosterone (t) pulses, which occur in response to social interactions, as elegantly developed by wingfield and colleagues. we focu ... | 2020 | 31778720 |
| sex-dependent effects of paternal deprivation and chronic variable stress on novel object recognition in adult california mice (peromyscus californicus). | early-life stress exposure can confer vulnerability for development of psychiatric illnesses and impaired cognition in adulthood. it is well-known that early-life stress can dysregulate the hypothalamic-pituitary-adrenal (hpa) axis in a sex-dependent manner. specifically, uniparental rodent models of prolonged disrupted mother-offspring relationships (e.g., maternal separation) have demonstrated greater alterations in stress responsivity in adult males, compared to females. also, chronic early-l ... | 2020 | 31669457 |
| consequences of placentophagia by adult virgin male california mice (peromyscus californicus). | placentophagia increases parental motivation in sexually inexperienced adult female rodents. we hypothesized that placenta ingestion has similar effects in virgin male california mice (peromyscus californicus), a monogamous rodent in which fathers provide extensive care for their offspring. to test this hypothesis, we administered either a conspecific's placenta in oil or oil alone to adult virgin males via oral gavage. one, 7 or 24 hours later, each male underwent a 1-hour behavior test with ei ... | 2019 | 31226336 |
| rapid effects of testosterone on social decision-making in a monogamous california mice (peromyscus californicus). | social animals must cope with challenges and opportunities by adjusting how they react to a salient stimulus. here we use california mice (peromyscus californicus) and investigate the mechanisms underlying social decision-making by studying (i) rapid effects of testosterone (t) pulses on a male's decisions to approach a novel male (challenge) versus a receptive female (opportunity), and (ii) whether social experience shapes how such effects are manifested. in experiment 1, we found that sexually ... | 2019 | 31220461 |
| early genistein exposure of california mice and effects on the gut microbiota-brain axis. | human offspring encounter high amounts of phytoestrogens, such as genistein (gen), through maternal diet and soy-based formulas. such chemicals can exert estrogenic activity and thereby disrupt neurobehavioral programming. besides inducing direct host effects, gen might cause gut dysbiosis and alter gut metabolites. to determine whether exposure to gen affects these parameters, california mice (peromyscus californicus) dams were placed 2 weeks prior to breeding and throughout gestation and lacta ... | 2019 | 31189133 |
| differential gene expression in relation to mating system in peromyscine rodents. | behaviors that increase an individual's exposure to pathogens are expected to have important effects on immunoactivity. because sexual reproduction typically requires close contact among conspecifics, mating systems provide an ideal opportunity to study the immunogenetic correlates of behaviors with high versus low risks of pathogen exposure. despite logical links between polygynandrous mating behavior, increased pathogen exposure, and greater immunoactivity, these relationships have seldom been ... | 2019 | 31161013 |
| effects of single parenthood on mothers' behavior, morphology, and endocrine function in the biparental california mouse. | motherhood is energetically costly for mammals and is associated with pronounced changes in mothers' physiology, morphology and behavior. in ~5% of mammals, fathers assist their mates with rearing offspring and can enhance offspring survival and development. although these beneficial consequences of paternal care can be mediated by direct effects on offspring, they might also be mediated indirectly, through beneficial effects on mothers. we tested the hypothesis that fathers in the monogamous, b ... | 2019 | 31153926 |
| effects of short- and long-term cold acclimation on morphology, physiology, and exercise performance of california mice (peromyscus californicus): potential modulation by fatherhood. | california mice (peromyscus californicus) differ from most other mammals in that they are biparental, genetically monogamous, and (compared with other peromyscus) relatively large. we evaluated effects of cold acclimation on metabolic rate, exercise performance, and morphology of pair-housed male california mice, as well as modulation of these effects by fatherhood. in experiment 1, virgin males housed at 5° or 10 °c for approximately 25 days were compared with virgins housed at standard vivariu ... | 2019 | 31073767 |
| plasticity of paternity: effects of fatherhood on synaptic, intrinsic and morphological characteristics of neurons in the medial preoptic area of male california mice. | parental care by fathers enhances offspring survival and development in numerous species. in the biparental california mouse, peromyscus californicus, behavioral plasticity is seen during the transition into fatherhood: adult virgin males often exhibit aggressive or indifferent responses to pups, whereas fathers engage in extensive paternal care. in this species and other biparental mammals, the onset of paternal behavior is associated with increased neural responsiveness to pups in specific bra ... | 2019 | 30802534 |
| genomic analysis of mhc-based mate choice in the monogamous california mouse. | variation at major histocompatibility complex (mhc) genes is thought to be an important mechanism underlying mate choice in vertebrates, with individuals typically predicted to prefer mhc-dissimilar reproductive partners. however, analyses based on individual mhc loci have generated contradictory results regarding the role of these genes in mate-choice decisions. to provide a more comprehensive assessment of relationships between mhc variation and mating behavior, we used an exome capture strate ... | 2020 | 30214134 |
| paternal care impacts oxytocin expression in california mouse offspring and basal testosterone in female, but not male pups. | natural variations in parenting are associated with differences in expression of several hormones and neuropeptides which may mediate lasting effects on offspring development, like regulation of stress reactivity and social behavior. using the bi-parental california mouse, we have demonstrated that parenting and aggression are programmed, at least in part, by paternal behavior as adult offspring model the degree of parental behavior received in development and are more territorial following high ... | 2018 | 30210315 |
| social environment affects central distribution of estrogen receptor-α in peromyscus californicus. | social environment has well-established effects on an animal's social behavior and associated neuroendocrine responses. the presence of estrogen receptor alpha (erα) in limbic system brain regions is related to the expression of a variety of social, reproductive and aggressive behaviors. we hypothesized that alterations to the social environment, specifically social isolation, would cause changes in erα throughout the limbic system. the number of erα immunoreactive (erα-ir) cells within specific ... | 2018 | 30145237 |
| the progesterone challenge: steroid hormone changes following a simulated territorial intrusion in female peromyscus californicus. | there is a growing body of evidence that the rapid but transient increase in male androgens, particularly testosterone (t), following a single social encounter such as a territorial intrusion occurs in a wide array of vertebrate taxa. yet, this phenomenon, often called the challenge hypothesis, has rarely been investigated in females. moreover, when studying male challenge effects, researchers have rarely investigated other hormones that can be important to the expression of aggression, such as ... | 2003 | 14609541 |
| enduring effects of paternal deprivation in california mice (peromyscus californicus): behavioral dysfunction and sex-dependent alterations in hippocampal new cell survival. | early-life experiences with caregivers can significantly affect offspring development in human and non-human animals. while much of our knowledge of parent-offspring relationships stem from mother-offspring interactions, increasing evidence suggests interactions with the father are equally as important and can prevent social, behavioral, and neurological impairments that may appear early in life and have enduring consequences in adulthood. in the present study, we utilized the monogamous and bip ... | 2018 | 29487509 |
| behavioral and endocrine consequences of placentophagia in male california mice (peromyscus californicus). | ingestion of placenta by mammalian mothers can lead to changes in pain sensitivity, hormone levels, and behavioral responses to newborns. in some biparental mammals, males, in addition to females, ingest placenta when their offspring are born. in the monogamous, biparental california mouse (peromyscus californicus), males first become attracted to placenta when cohabitating with their pregnant mate, and virgin males administered placenta are less neophobic than males given oil vehicle. in this s ... | 2018 | 29452152 |
| activation of kappa opioid receptors in the dorsal raphe have sex dependent effects on social behavior in california mice. | kappa opioid receptor activation has been linked to stress and anxiety behavior, thus leading to kappa antagonists being popularized in research as potential anxiolytics. however, while these findings may hold true in standard models, the neuromodulatory effects of social defeat may change the behavioral outcome of kappa opioid receptor activation. previous research has shown that social defeat can lead to hyperactivity of serotonergic neurons in the dorsal raphe nucleus, and that inhibition of ... | 2018 | 29768187 |