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The extended pace-of-life syndrome (POLS) hypothesis suggests that variation in boldness-like behaviors has co-evolved with variation in life-history strategies within populations, yet both theoretically driven experiments and evidence for phenotypic correlations between boldness-like behaviors and reproduction-related activities are scarce. Here we test the prediction that more exploratory individuals should be willing to provide more effort into current reproduction than less exploratory ones by investigating the association between exploration behavior and parental effort in wild great tits ( Parus major). To this end, we assessed exploration behavior following a standardized assay. Then, we estimated individual willingness to provide parental effort into brood provisioning as (1) individual increase in nest visit rate after the brood had been artificially enlarged and (2) individual latency to return to the nest after this manipulation. Fast male explorers were quicker than slow explorers to return to the nest after the manipulation. Males paired with a partner of similar exploration score-either a fast or slow female explorer -increased their nest visit rate more than males paired with a partner of dissimilar exploration score. The relationship between exploration and parental effort then depended on one's partner's behavior. Our test thus provides only partial support for the extended POLS hypothesis and highlights the potential importance of the social environment in shaping the relationship between boldness-like behaviors and fitness-maximizing traits. [ABSTRACT FROM AUTHOR]

In birds, the duration of egg incubation (the time from incubation onset to hatching) can affect multiple components of nest success, but what affects incubation duration? Previous studies suggest that incubation duration is affected by both parental behavior and components of the egg, which have yet to be determined. One egg component that may be related to incubation behavior and the time until hatching is eggshell porosity, which affects the exchange of metabolic gasses and water vapor across the shell and, thus, the speed of embryonic development and incubation duration. We tested whether eggshell porosity was associated with the timing of incubation onset by female House Wrens ( Troglodytes aedon Vieillot, 1809), and whether porosity varied within clutches in a manner that might be associated with incubation periods and hatching patterns (i.e., synchronous vs. asynchronous hatching). Eggshell porosity was unrelated to the onset of maternal incubation and did not differ between early- and later-laid eggs within clutches, but differed significantly among females and covaried with egg size. We conclude that producing all eggshells of similar porosity within clutches, while adjusting incubation onset once most or all eggs are laid, provide facultative maternal control over variation in hatching patterns. [ABSTRACT FROM AUTHOR]

Recently, carotenoid pigments have received considerable attention as modulators of animal health and performance. While studies show that elevated carotenoid intake and accumulation can influence activities like parental care and escape-flight performance, little is known of how carotenoid status influences the expression of animal personality traits, which can be energy-demanding and entail survival costs but also rewarding in the context of foraging and mating. We experimentally investigated the effects of carotenoid availability on exploratory behavior and activity level, using adult males and females of two species of waterfowl: mallard ( Anas platyrhynchos ) and northern pintail ( Anas acuta ). We assessed behavior using a novel-environment test designed to measure an individual’s response to novel objects and a potential predator threat (fox urine scent). We found that carotenoid availability was positively associated with some aspects of exploratory behavior: birds with higher concentrations of circulating carotenoids entered the test arena sooner and approached and entered predator-scented bedding material more frequently than birds with low carotenoid concentrations. These results suggest that the availability of carotenoid resources can influence personality traits in waterfowl, and we discuss putative physiological mechanisms underlying this effect. [ABSTRACT FROM AUTHOR]

The main objective of this work was to determine whether the five founding castes defined in the Lidia cattle breed actually have an important contribution to the Spanish paternal genetic stock as well as to the paternal genetic origin support. A total of 1300 Bos taurus male individuals were genotyped for five microsatellites ( INRA189, UMN0103, UMN0307, BM861 and BYM1) and one indel ( ZFY10). Microsatellite and indel alleles were combined into haplotypes, identifying a total of 38 haplotypes, 11 of them belonging to haplogroup Y1 and 27 to haplogroup Y2. Ten different haplotypes were found in the Lidia cattle breed, with five being exclusive to this breed. Our results agree with different male genetic stocks in the Lidia breed: one hypothetically representing the ancient Iberian bovine genetic stock (Gallardo, Navarra and Cabrera castes and some encastes from Vistahermosa) and a second one that is the result of the more recent breeding strategy of choosing the most aggressive individuals from traditional herds (including some Vistahermosa encastes and the Vazqueña caste). In terms of conservation, it would be better to not consider this breed as a unit but to consider the caste, or even better the encaste, as the target of putative conservation efforts. [ABSTRACT FROM AUTHOR]

Individual differences in maternal behavior toward, and investment in, offspring can have lasting consequences, particularly among primate taxa characterized by prolonged periods of development over which mothers can exert substantial influence. Given the role of the neuroendocrine system in the expression of behavior, researchers are increasingly interested in understanding the hormonal correlates of maternal behavior. Here, we examined the relationship between maternal behavior and physiological stress levels, as quantified by fecal glucocorticoid metabolite (FGM) concentrations, in lactating chimpanzees, Pan troglodytes schweinfurthii, at Gombe National Park, Tanzania. After accounting for temporal variation in FGM concentrations, we found that mothers interacted socially (groomed and played) with and nursed their infants more on days when FGM concentrations were elevated compared to days when FGM concentrations were within the range expected given the time of year. However, the proportion of time mothers and infants spent in contact did not differ based on FGM concentrations. These results generally agree with the suggestion that elevated GC concentrations are related to maternal motivation and responsivity to infant cues and are the first evidence of a hormonal correlate of maternal behavior in a wild great ape. [ABSTRACT FROM AUTHOR]

Previous breeding experience affects parental care, yet in biparental species it is unclear how the inexperience of only one parent influences parental dynamics and division of labour. Using the biparental convict cichlid, Amatitlania siquia , I assessed how female breeding experience affects male and female parental behaviour. Females that either had bred (experienced) or were virgins (inexperienced) were paired with experienced males. Inexperienced females were less likely to form pairs and took longer to spawn. Female experience also affected parental division of labour between direct offspring care and territory defence. Female behaviour was compared in the presence and absence of their male partners. When males were present, all females divided their time similarly: more time was spent in direct care. When male mates were removed, experienced females divided their time equally between territory defence and direct care, while inexperienced females continued to spend more time in direct care. Males paired to inexperienced females divided their time equally between territory defence and direct care, while males paired to experienced females spent more time in defence. Males were also more aggressive towards experienced females. Overall, experienced females tended to adopt the male-typical role of defence, which probably caused the increased intrapair conflict in these pairs. This aggression helps explain why both experienced and inexperienced females showed similar role choices in the presence of their male partner and supports previous claims that male aggression helps maintain the division of labour in this species. Female inexperience potentially presents a trade-off for males: males paired to inexperienced females engaged in less intrapair conflict, but showed less division of labour between parental roles than is typical and were less likely to pair and spawn. The effect of female experience on division of labour, parental dynamics and pair bonding success probably influences other factors such as mate choice, effectiveness of parental care and overall fitness. [ABSTRACT FROM AUTHOR]

Spontaneously hypertensive rats (SHR) develop cardiovascular and metabolic pathology in adulthood when their circadian system exhibits significant aberrances compared with healthy control rats. This study was aimed to elucidate how the SHR circadian system develops during ontogenesis and to assess its sensitivity to changes in maternal-feeding regime. Analysis of ontogenesis of clock gene expression rhythms in the suprachiasmatic nuclei, liver and colon revealed significant differences in SHR compared with Wistar rats. In the suprachiasmatic nuclei of the hypothalamus (SCN) and liver, the development of a high-amplitude expression rhythm selectively for Bmal1 was delayed compared with Wistar rat. The atypical development of the SHR circadian clocks during postnatal ontogenesis might arise from differences in maternal behavior between SHR and Wistar rats that were detected soon after delivery. It may also arise from higher sensitivity of the circadian clocks in the SHR SCN, liver and colon to maternal behavior related to changes in the feeding regime because in contrast to Wistar rat, the SHR SCN and peripheral clocks during the prenatal period and the hepatic clock during the early postnatal period were phase shifted due to exposure of mothers to a restricted feeding regime. The maternal restricted feeding regime shifted the clocks despite the fact that the mothers were maintained under the light/dark cycle. Our findings of the diverse development and higher sensitivity of the developing circadian system of SHR to maternal cues might result from previously demonstrated differences in the SHR circadian genotype and may potentially contribute to cardiovascular and metabolic diseases, which the animal model spontaneously develops. [ABSTRACT FROM AUTHOR]

Nest prospecting, that is, visiting potential future nest sites, may be a widespread bird behavior. Here we describe apparent prospecting while nesting by white-rumped swallows (Hirundinidae, Aves). In southern Brazil, birds tagged with passive-integrated transponders (PIT-tags) and breeding in nest boxes with PIT-tag readers: (1) often visited nest boxes that were in use by apparently unrelated birds (54 % of nests were visited at least once), (2) visited other boxes while caring for their own nestlings, (3) tended to have smaller broods than birds that were not recorded visiting, and (4) did not have a preference for any particular box. These patterns do not indicate any clear explanation for nest visiting, but they do show that prospecting is done by floaters (non-breeders) as well as actively breeding individuals. We suggest that these visits occur when time is available and that visitors may be assessing the availability of future nest sites. [ABSTRACT FROM AUTHOR]

In conspecific brood parasitism, some females ("parasites") lay eggs in nests of other females of the same species ("hosts"). This reproductive tactic is particularly common in waterfowl, in which studies suggest that parasites are often related to the host. Here, we test the hypothesis that hosts may discriminate and reject unrelated parasites. Based on observations and >4100 h of digital video film, we analyze behavioral interactions at 65 nests of High Arctic common eiders during the laying sequence. We also estimate parasitism and host-parasite relatedness by albumen fingerprinting of 975 eggs from 232 nests. Among the video-filmed nests in which interactions were recorded during the egg-laying period, 11 had eggs from 2 females. At 8 of these 11 nests, there was overt female aggression and significantly lower host-parasite relatedness (mean coefficient of relationship r = -0.40) than in the nests with tolerant or no interactions (r = 0.91). The results demonstrate active female kin discrimination in common eiders, used against nonrelatives that try to lay eggs in the nest. Other females trying to access the nest were often prevented from doing so: in 65% of 34 such attempts, the sitting female rejected the intruder. Brood "parasitism" in eiders and other waterfowl is complex, ranging from violent female conflict and parasitic exploitation of the host's parental care to nest takeover and potential kin selection favoring acceptance of related parasites. These and other aspects of female sociality in eiders are discussed; in some respects, they may resemble certain long-lived matriarchal mammals. [ABSTRACT FROM AUTHOR]

Studies on juvenile survival have mainly focused on the effects of environmental conditions and maternal traits. However, growing evidence indicates that the ability of parents to care for their young and the offspring developmental behaviors could be key determinants of their survival. We examined the relative influence of (1) environmental conditions, (2) offspring traits, (3) maternal traits, (4) maternal care behaviors, and (5) offspring developmental behaviors on kid survival to weaning and to 1 year old in mountain goats ( Oreamnos americanus). Offspring development and maternal care directly affected offspring survival, and this more importantly than did environmental conditions and maternal traits. Frequency of play strongly increased survival before weaning. Greater maternal care increased offspring survival during winter, directly and indirectly through kid mass. Kid mass was also a major determinant of both summer and winter survival. Environmental conditions mainly influenced summer survival while maternal characteristics indirectly affected winter survival through an effect on kid mass. Behavioral adaptations of maternal care and offspring development to local selective pressures can lead to local adaptations and have greater implications in population dynamic studies than previously believed. [ABSTRACT FROM AUTHOR]

Premature breaking of the maternal bond between a cow and her calf triggers a strong behavioural response which renders separation and weaning major welfare challenges in suckling systems. Fence-line separation and weaning allowing physical contact has been evaluated for beef cattle and is claimed to reduce stress at separation. The objective of this study was to compare the post-separation behavioural response of cow–calf pairs separated either with a fence-line (FL, n = 8 pairs) allowing physical contact or with a solid wall (SW, n = 8 pairs) allowing merely auditory contact. After separation, all calves were offered milk (2.0 L, thrice a day) from a teat bottle to reduce the effect of hunger. Behaviours were recorded for 4 h at days 0 (day of separation), 1, 2, 3 and 4 from which we calculated the total behavioural reaction (area under the curve, AUC). Treatment differences were analysed with two samples Wilcoxon test. Most of the post-separation responses occurred during day 0–2. Results show that FL calves performed less high-pitched (open mouthed) vocalizations as compared to SW calves ( P = 0.003). Median number of calls/4 h and range for FL vs. SW calves respectively were: day 0 ; 13 (0–94) vs. 361 (2–658), day 1 ; 10 (1–247) vs. 274 (18–872), day 2 ; 0 (0–4) vs. 48 (0–365), day 3 ; 0 (0–1) vs. 4 (0–135) and day 4 ; 0 (0–2) vs. 18 (0–84). Calves separated with FL also showed a lower frequency than SW calves ( P = 0.003) of alert behaviour defined as high-head posture, pointed ears with focus towards the cow (median percentage of observations and range for FL and SW calves respectively): day 0 ; 23 (0–50) vs. 26 (0–50), day 1 ; 3 (0–12) vs. 12 (4–36), day 2 ; 0 (0–6) vs. 12 (0–18), day 3 ; 0 (0–2) vs. 3 (0–18) and day 4 ; 0 (0–2) vs. 15 (0–28). No significant treatment differences were found for other calf behaviours or in the post-separation behavioural responses of the cow. This is the first study to quantitatively assess two different vocalizations in response to separation; low-pitched vocalizations (with closed mouth) and high-pitched vocalizations in response to separation. Recordings of high-pitched vocalization seem to be a promising tool for assessing distress at separation. In conclusion, FL separation allowing physical contact may reduce the vocal response and alert behaviour of calves. [ABSTRACT FROM AUTHOR]

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 the 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 mass and if so, which specific social/reproductive factor(s) might contribute to these changes. We compared mean weekly body masses over a 5-week period in (1) males housed with another male versus males housed with a non-reproductive (tubally ligated) female; (2) males housed with a tubally ligated female versus males housed with a female that was undergoing her first pregnancy; (3) experienced fathers housed with versus without pups during their mate's subsequent pregnancy. Body mass did not differ between males housed with another male and those housed with a non-reproductive female; however, males housed with a non-reproductive female were significantly heavier than those housed with a primigravid female. Among experienced fathers, those housed with pups from their previous litter underwent significant increases in body mass across their mates' pregnancy, whereas fathers housed without pups did not. These results suggest that male body mass is reduced by cohabitation with a breeding (pregnant) female, but not by cohabitation with a non-reproductive female, and that increases in body mass across the mate's pregnancy are associated with concurrent care of offspring rather than cohabitation with a pregnant female. Additional work is needed to determine the mechanisms and functional significance, if any, of these changes in male body mass with reproductive condition. [ABSTRACT FROM AUTHOR]

Parental care often produces a trade-off between meeting nutritional demands of offspring and the duties of offspring protection, especially in altricial species. Parents have to leave their young unattended for foraging trips, during which nestlings are exposed to predators. We investigated how rodent mothers of altricial young respond to risk of nest predation in their foraging decisions. We studied foraging behavior of lactating bank voles ( Myodes glareolus) exposed to a nest predator, the common shrew ( Sorex araneus). We conducted the experiment in summer (high resource provisioning for both species) and autumn (less food available) in 12 replicates with fully crossed factors 'shrew presence' and 'season.' We monitored use of feeding stations near and far from the nest as measurement of foraging activity and strategic foraging behavior. Vole mothers adapted their strategies to shrew presence and optimized their foraging behavior according to seasonal constraints, resulting in an interaction of treatment and season. In summer, shrew presence reduced food intake from feeding stations, while it enhanced intake in autumn. Shrew presence decreased the number of visited feeding stations in autumn and concentrated mother's foraging efforts to fewer stations. Independent of shrew presence or season, mothers foraged more in patches further away from the nest than near the nest. Results indicate that females are not investing in nest guarding but try to avoid the accumulation of olfactory cues near the nest leading a predator to the young. Additionally, our study shows how foraging strategies and nest attendance are influenced by seasonal food provision. [ABSTRACT FROM AUTHOR]

The Trivers-Willard hypothesis predicts that, in polygynous and sexually dimorphic mammals, mothers able to provide a large amount of care should produce more sons. Tests of this prediction, however, have generated equivocal results, possibly because multiple factors, including environmental conditions, simultaneously influence progeny sex ratio. We tested the influence of maternal mass, condition, size, previous reproduction and age class on offspring sex ratio in two populations of eastern grey kangaroos ( Macropus giganteus). In one population, heavier and taller mothers produced more sons than did lighter mothers, but maternal condition had no effect on progeny sex ratio. Primiparous females, however, produced an even offspring sex ratio despite being smaller than multiparous females. A strong year effect on progeny sex ratio suggested a likely effect of environmental conditions. In the second population, none of the variables tested influenced progeny sex ratio. Different environmental conditions between the two populations could partly explain these results. Because maternal size and mass likely correlate with reproductive potential, we suggest that our results support the Trivers-Willard hypothesis, but other variables likely also influence progeny sex ratio. [ABSTRACT FROM AUTHOR]

Parental behavior is important for the development of mammalian offspring. Research on the mechanisms underlying parental behavior, however, has been largely restricted to rodent models. As a consequence, although research on parent–infant relationships has been conducted using macaque monkeys for more than half a century, little is known about the neural mechanisms and brain regions associated with such behaviors in primates. This article reviews parental behavior and its endocrinological mechanisms in marmosets and tamarins, both cooperative breeders in the callitrichid family, and compares these findings with studies of macaque monkeys. The paper examines the similarities and differences between marmosets and humans, and suggests the possibility that marmosets can be a model for future studies of the neural underpinnings and endocrinology underlying human parental behavior. [ABSTRACT FROM AUTHOR]

Beluga whales ( Delphinapterus leucas) have a protracted nursing period estimated to last from 6-32 months, although current estimates of beluga nursing duration are derived using approaches subject to capture bias. Recent studies have shown stable isotope profiles of dentin growth layer groups (GLGs) in marine mammal teeth serve as a reliable nursing proxy and can be used to assess individual weaning patterns. We measured stable isotope ratios of nitrogen (δ15N) and carbon (δ13C) of dentin GLGs in teeth from eastern Canadian Arctic belugas to estimate weaning age and assess relative contributions of milk and solid food during the nursing period. δ15N declines of ∼1‰ over the first 3 GLGs of most individuals were interpreted as evidence of weaning. Individual δ15N profiles indicated 15 of 27 whales were completely weaned by the end of their 2nd year, although a number of whales were weaned by the end of their 1st or 3rd year (9 and 3, respectively). Intermediate GLG2 δ15N values relative to GLGs 1 and 3 indicated most whales consumed a mixture of milk and solid food during their 2nd year, consistent with gradual weaning. Contrary to predictions based on parental care theory, nursing duration was not related to relative GLG width (used as a proxy for somatic growth) and did not differ for females and males, or among populations. δ13C variation was not a reliable indicator of nursing duration, as approximately half of the whales showed no ontogenetic δ13C patterns across GLGs deposited over the nursing period. This study provides novel life history information, which may inform beluga conservation and management decisions, and indicates belugas share prolonged nursing duration marked by individual variation observed in other odontocetes. [ABSTRACT FROM AUTHOR]

During the austral winter, adult female southern right whales Eubalaena australis enter the South African coastal waters to give birth and raise their young. Most births take place over a 4-month period, when the females congregate in specific coastal areas or nursery grounds for up to a recorded maximum of 105 days. At this time, the density of cow-calf pairs in nursery areas can reach as high as 3.2 pairs/km2 over 26 km of coastline. Although a single young is born and suckled exclusively for 7 months to a year, recent observations on nursery grounds include 3 incidents where apparently abandoned/orphaned calves-of-the-year have been seen associating with a minimum of 2-3 different cow-calf pairs over periods of 11-38 days. Attempts to suckle from these females have been noted in 2 of the cases, with the response of the female varying from extreme avoidance to apparent tolerance. In one instance where the observations of the same trio extended over 21 days, the non-offspring appeared to compete at least equally with the offspring, even though the mother directed her evasive tactics more at the non-offspring than her own calf. At the same time, both of the calves exhibited some growth in length when compared with the size of the adult female: their subsequent survival is unknown. Non-offspring nursing in monotocous species is generally rare, and the costs to the female potentially high: this is certainly the case for seasonally feeding mysticetes such as the right whale, where the costs of lactation cannot be recovered until the cow resumes feeding about 4 months after parturition. Hence, it is perhaps not surprising that these are the first recorded observations of contemporaneous nursing attempts by offspring and non-offspring calves of any mysticete. [ABSTRACT FROM AUTHOR]

Studies of siblings have focused mainly on their competitive interactions and to a lesser extent on their cooperation. However, competition and cooperation are at opposite ends on a continuum of possible interactions and the nature of these interactions may be flexible with ecological factors tipping the balance toward competition in some environments and cooperation in others. Here we show that the presence of parental care and the density of larvae on the breeding carcass change the outcome of sibling interactions in burying beetle broods. With full parental care there was a strong negative relationship between larval density and larval mass, consistent with sibling competition for resources. In the absence of care, initial increases in larval density had beneficial effects on larval mass but further increases in larval density reduced larval mass. This likely reflects a density-dependent shift between cooperation and competition. In a second experiment, we manipulated larval density and removed parental care. We found that the ability of larvae to penetrate the breeding carcass increased with larval density and that feeding within the carcass resulted in heavier larvae than feeding outside the carcass. However, larval density did not influence carcass decay. [ABSTRACT FROM AUTHOR]

Breeding animals must balance their current reproductive effort with potential costs to their own survival and consequently to future reproduction. Life-history theory predicts that variation in reproductive investment should be based on fecundity and life expectancy with longer-lived species favoring their own survival over parental investment. Recently, variation in parental risk taking was also linked with differences in cognition suggesting a potential trade-off between cognitive ability and risk taking. Here, we tested whether mountain chickadees from two different elevations with known differences in cognitive ability differ in their parental risk taking by comparing the responses of nesting birds to a potential predator. Higher elevations are associated with shorter breeding season limiting renesting opportunities, but chickadees at high elevations also have better cognitive abilities, which might be potentially associated with better survival. Compared to lower elevations, high-elevation chickadees laid larger clutches, showed longer latencies to return to the nest in the presence of a hawk, had lower fledging success, and exhibited higher rate of complete nest failures. Nestling development among successful nests, however, was similar between elevations. These data are not consistent with life-history hypothesis because birds at high elevation invest more in the clutch, while at the same time take less risk when facing potential danger to themselves, which could jeopardize their current reproductive success. These data, however, are consistent with the hypothesis that better cognitive abilities might be associated with less parental risk taking. [ABSTRACT FROM AUTHOR]

Offspring begging can be triggered by a variety of acoustic, visual or chemical cues from the parents. In many birds, nestlings use information derived from these cues to discriminate between individual parents or different classes of adults. Although begging occurs in some insects, we know very little about discrimination between adults by insect larvae. Here, we examine whether begging larvae in the burying beetle Nicrophorus vespilloides can discriminate between individual parents or different classes of adults. We found that larvae showed no discrimination between male and female beetles, but that they begged more towards breeding beetles than towards non-breeding ones. These results were robust regardless of whether larvae had been reared in presence or absence of adult beetles, thus suggesting that larval discrimination is based on an innate template that requires no prior exposure to adult beetles. We also found that larvae begged more towards unfamiliar beetles than towards familiar ones, suggesting that they can learn to discriminate between individual parents based on cues about familiarity. We conclude that insect larvae may benefit from discriminating between different classes of adult beetles, as it allows them to lower the costs associated with begging in response to irrelevant environmental cues (costly in terms of wasted effort) and with not begging in response to the presence of caring parents (costly in terms of lost feeding opportunities). [ABSTRACT FROM AUTHOR]

Contents The aim of this work was to evaluate the influence of maternal and embryonic genotype on prenatal survival and foetal growth during pregnancy. Embryos were recovered at 48 h of gestation from two different donor lines (R = 46 and A = 40) and transferred to nulliparous recipient does (26 R and 24 A). Each recipient doe received six embryos into one oviduct from line R, and six embryos form line A into the other. Laparoscopy was performed at Day 14 to determine implantation rate. Recipient females were slaughter at Days 14, 24 and 30 (12, 24, and 14, respectively) to determine the number of live foetuses and the weight of live foetuses, foetal placenta and maternal placenta. A transcriptome analysis was performed to search for differences between foetal placentas at Days 14 and 24 of development. Prenatal survival at Days 14, and 24 was affected by embryonic genotype and determined by maternal genotype at Day 30. Foetal weight at Day 14 was influenced by both genotypes, being the weight higher for group A/A (0.29 ± 0.01 g vs 0.19 ± 0.01 g, for group R/R). However, both genotypes were determinant for foetal placenta weight at Day 24, while those genotypes affected maternal placenta weight at Day 30. Nevertheless, no differences in foetal placenta at transcriptome level and progesterone and IGF-I plasma levels in recipient does were found. In conclusion, results indicate that the influence of embryo and maternal genotype on the prenatal survival and growth seems to be changing over gestation. [ABSTRACT FROM AUTHOR]

It has long been understood that the pathogenesis of complex diseases such as diabetes includes both genetic and environmental components. More recently, it has become clear that not only does an individual’s environment influence their own metabolism, but in some cases, the environment experienced by their parents may also contribute to their risk of metabolic disease. Here, we review the evidence that parental diet influences metabolic phenotype in offspring in mammals and provide a current survey of our mechanistic understanding of these effects. [ABSTRACT FROM AUTHOR]

Maternal care is indispensable for the survival of mammalian offspring. Although virgin female mice avoid pups, they actively display maternal behavior after parturition. To determine which brain regions are involved in the qualitative differences observed in the responses of virgin and lactating females to pups, we compared the expression of c-Fos, which is a marker of neuronal activation, in brain regions involved in regulating maternal behavior. Pup presentation increased the number of c-Fos-positive cells in both the ventrotegmental area (VTA) and nucleus accumbens to a greater extent in lactating females than in virgin females. The bed nucleus of striaterminalis (BNST), which innervates VTA neurons to regulate both aversive and rewarding responses, showed increased number of c-Fos-positive cells following pup presentation in virgin females, butnotin lactating females. On the other hand, the number of c-Fos-positive cells in the medial preoptic area (MPOA) increased in both virgin and lactating females. The number of c-Fos-positive cells in lactating females not presented with pups was high and similar to that in virgin females presented with pups. Moreover, c-Fos-positive GABAergicneurons projecting from the MPOA to the BNST was confirmed using a retrograde tracer Fluorogold in lactating females. Our results indicate that constitutive GABAergic modulation projecting from the MPOA may suppress the activity of BNST neurons and prevent avoidance responses to pups in lactating females. [ABSTRACT FROM AUTHOR]

In monogamous mammals paternal care plays an important role in the neural and behavioral development of offspring. However, the neuroendocrine mechanisms underlying paternal behavior remain poorly understood. Here, we investigate the association between natural variation in paternal responsiveness and central levels of oxytocin (OT) and estrogen receptor alpha (ERα). We used the frequency of licking and grooming behavior to distinguish low paternal responsiveness and high paternal responsiveness in virgin mandarin voles ( Microtus mandarinus). Males that engaged in high paternal behavior had elevated levels of OT immunoreactive neurons in the paraventricular nuclei of the hypothalamus and supraoptic nuclei of the hypothalamus compared with males that displayed low paternal behavior. Likewise, males of high paternal responsiveness had more ERα immunoreactive neurons in the medial preoptic area, bed nucleus of the stria terminalis, arcuate nucleus of the hypothalamus and medial amygdaloid nucleus compared to low responsive males. The level of ERα immunoreactive neurons in the ventromedial hypothalamic nucleus was lower in highly paternal males compared to less paternal males. These results suggest that natural variation in paternal responsiveness may be directly related to variation in central OT and ERα. [ABSTRACT FROM AUTHOR]

The hypothesis that maternal effects act as an adaptive bridge in translating maternal environments into offspring phenotypes, and thereby affecting population dynamics has not been studied in the well-controlled fields., In this study, the effects of maternal population density on offspring stress axis, reproduction and population dynamics were studied in root voles ( Microtus oeconomus). Parental enclosures for breeding offspring were established by introducing six adults per sex into each of 4 (low density) and 30 adults per sex into each of another 4 (high density) enclosures. Live-trapping started 2 weeks after. Offspring captured at age of 20-30 days were removed to the laboratory, housed under laboratory conditions until puberty, and subsequently used to establish offspring populations in these same enclosures, after parental populations had been removed. [Correction added on 8 January 2015 after first online publication: '10-20 days' has been changed to '20-30 days.'] Offspring from each of the two parental sources were assigned into four enclosures with two for each of the two density treatments used in establishing parental populations (referred to as LL and LH for maternally unstressed offspring, assigned in low and highdensity, and HL and HH for maternally stressed offspring, assigned in low and high density). Faecal corticosterone metabolites ( FCM) levels, offspring reproduction traits and population dynamics were tested following repeated live-trapping over two seasons., Differential fluctuations in population size were observed between maternally density-stressed and density-unstressed offspring. Populations in LL and LH groups changed significantly in responding to initial density and reached the similar levels at beginning of the second trapping season. Populations in HL and HH groups, however, were remained relatively steady, and in HL group, the low population size was sustained until end of experiment. Maternal density stress was associated with FCM elevations, reproduction suppression and body mass decrease at sexual maturity in offspring. The FCM elevations and reproduction suppression were independent of offspring population density and correlated with decreased offspring quality., These findings indicate that intrinsic state alterations induced by maternal stress impair offspring capacity in response to immediate environment, and these alterations are likely mediated by maternal stress system. The maladaptive reproduction suppression seen in HL group suggests intrinsic population density as one of ecological factors generating delayed density-dependent effects. [ABSTRACT FROM AUTHOR]

Parental care entails physiological costs to the mother. These costs, even if dramatic, are usually reversible and do not result in mortality of the mother. In the spider Stegodyphus lineatus Latreille 1817 (Eresidae), maternal care is extreme and irreversible: mothers regurgitate food for the young and then die when consumed by them (matriphagy). We examined whether the mother's midgut tissues undergo structural changes in preparation for regurgitation and matriphagy. Our histological data show that the midgut diverticula (MD) tissues start to degrade during the egg sac incubation period. When the young emerge from the egg sac, the midgut tissues are partly liquefied and are retained within the MD. The degradation process intensifies when the female feeds her young by regurgitation and liquid tissue is observed within and among the diverticula lobes. The presence of the lumen of a diverticulum during the regurgitation process suggests that degenerated tissues enter the lumen and form the regurgitated fluid. At matriphagy, the abdomen is filled with liquid containing nutritional vacuoles, which the young imbibe after piercing the female's abdomen. We conclude that the MD undergoes a gradual degradation process that maximizes the nutritional potential of the female's body and finally enables complete consumption of her soma. These changes are consistent with the extreme semelparous reproductive system of S. lineatus, where a female invests all of her resources into a single reproductive event. This is the first demonstration of the mechanism underlying suicidal maternal care in an arthropod. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

On coral reefs in New Caledonia, the eggs of demersal-spawning fishes are consumed by turtle-headed seasnakes ( Emydocephalus annulatus). Fish repel nest-raiding snakes by a series of tactics. We recorded 232 cases (involving 22 fish species) of antipredator behaviour towards snakes on a reef near Noumea. Blennies and gobies focused their attacks on snakes entering their nests, whereas damselfish ( Pomacentridae) attacked passing snakes, as well as nest-raiders (reflecting territorial defence). Biting the snake was the most common form of attack, although damselfish and blennies also slapped snakes with the tail, or (blennies only) plugged the nest entrance with the parent fish's body. Gobies rarely defended the nest, although they sometimes bit or threw sand at the snake. A snake was more likely to flee if it was attacked before it began feeding rather than after it found the eggs (82% versus 3% repelled) and if bitten on the head rather than the body (68% versus 53%). Tail-slaps were not effective, although plugging the burrow and throwing sand often caused snakes to flee. These strong patterns reflect phylogenetic variation in fish behaviour (e.g. damselfish detect a snake approach sooner than do substrate-dwelling blennies and gobies) coupled with intraspecific variation in snake diets. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114, 415-425. [ABSTRACT FROM AUTHOR]

This article is part of a Special Issue “Chemosignals and Reproduction”. This paper reviews the role of chemosignals in the socio-sexual interactions of female mice, and reports two experiments testing the role of pup-derived chemosignals and the male sexual pheromone darcin in inducing and promoting maternal aggression. Female mice are attracted to urine-borne male pheromones. Volatile and non-volatile urine fractions have been proposed to contain olfactory and vomeronasal pheromones. In particular, the male-specific major urinary protein (MUP) MUP20, darcin, has been shown to be rewarding and attractive to females. Non-urinary male chemosignals, such as the lacrimal protein ESP1, promote lordosis in female mice, but its attractive properties are still to be tested. There is evidence indicating that ESP1 and MUPs are detected by vomeronasal type 2 receptors (V2R). When a female mouse becomes pregnant, she undergoes dramatic changes in her physiology and behaviour. She builds a nest for her pups and takes care of them. Dams also defend the nest against conspecific intruders, attacking especially gonadally intact males. Maternal behaviour is dependent on a functional olfactory system, thus suggesting a role of chemosignals in the development of maternal behaviour. Our first experiment demonstrates, however, that pup chemosignals are not sufficient to induce maternal aggression in virgin females. In addition, it is known that vomeronasal stimuli are needed for maternal aggression. Since MUPs (and other molecules) are able to promote intermale aggression, in our second experiment we test if the attractive MUP darcin also promotes attacks on castrated male intruders by lactating dams. Our findings demonstrate that the same chemosignal, darcin, promotes attraction or aggression according to female reproductive state. [ABSTRACT FROM AUTHOR]

This article is part of a Special Issue “Chemosignals and Reproduction”. In mammalian species, odor cues emitted by the newborn are essential to establish maternal behavior at parturition and coordinate early mother–infant interactions. Offspring odors become potent attractive stimuli at parturition promoting the contact with the young to ensure that normal maternal care develops. In some species odors provide a basis for individual recognition of the offspring and highly specialized neural mechanisms for learning the infant signals have evolved. Both the main and the accessory olfactory systems are involved in the onset of maternal care, but only the former contributes to individual odor discrimination of the young. Electrophysiological and neurochemical changes occur in the main olfactory bulb leading to a coding of the olfactory signature of the familiar young. Olfactory neurogenesis could also contribute to motherhood and associated learning. Parturition and interactions with the young influence neurogenesis and some evidence indicates a functional link between olfactory neurogenesis and maternal behavior. Although a simple compound has been found which regulates anogenital licking in the rat, studies identifying the chemical nature of these odors are lacking. Neonatal body odors seem to be particularly salient to human mothers who are able to identify their infant's odors. Recent studies have revealed some neural processing of these cues confirming the importance of mother–young chemical communication in our own species. [ABSTRACT FROM AUTHOR]

Coloration in birds can act as an important sexual signal in males, yet in many species, both sexes display bright colors. Social selection may account for this pattern, with more brightly colored individuals pairing together on the best territories. Mutual mate choice may also explain this, as males investing a great deal of parental care in the offspring should be choosy about their social mates. It is less clear whether this pattern of mate choice can apply to extra-pair partners as well. We examined western bluebirds ( Sialia mexicana) to determine whether more colorful individuals tended to pair with one another, both in social pairs and between females and their extra-pair partners. Both male and female western bluebirds display both UV-blue structural plumage and a melanin-based chestnut breast patch, although females are duller than males. Social pairs mated assortatively with regard to UV-blue brightness, but not chestnut coloration. There was no evidence that extra-pair partners mated assortatively, but males with brighter UV-blue coloration had fewer extra-pair offspring in their nests. Older males were more successful at siring extra-pair offspring, despite displaying no differences in coloration compared to younger males. Coloration did not play a role in determining extra-pair male success. These results suggest that coloration plays a role in the formation of social pairs, but not mate choice for extra-pair partners. [ABSTRACT FROM AUTHOR]

Within the 24 h prior to parturition sows are active and motivated to perform nest-building behaviour. The aim of this study was to investigate: (i) whether pre-partum activity (e.g. nesting and postural changes) could predict maternal behaviour 24 h post-partum (pp) and weight gain 24 h pp, and (ii) whether post-partum activity (post-partum nesting and postural changes) affect parts of the maternal behaviour 24 pp (e.g. first suckling, udder access, suckling duration) and piglet weight gain 24 h pp. Fifteen sows were housed in modified straw-bedded “walk-around” farrowing crates. Pre-partum nesting events and postural changes were recorded 24 h before parturition. During parturition the number of nesting behaviour and latency of the first sucking of the whole litter were recorded. Number of postural changes and duration of udder access were recorded 24 h after birth of the first piglet (BFP) during three time periods (during parturition, from the end of parturition to 12 h after BFP, and 12–24 h after BFP). The duration of suckling and sow responsiveness on the playback of piglets’ scream were recorded during two time periods (from the end of parturition to 12 h after BFP, and 12–24 h after BFP). Piglet BW gain was estimated 24 h after BFP. Data were analysed using proc GLM and MIXED and the probability of sow responsiveness using proc GENMOD in SAS. Pre-partum nesting 4 h before BFP was related with longer latency of the first sucking ( P < 0.01), with shorter duration of suckling ( P < 0.05) and with lower piglet BW gain ( P < 0.05). More nesting after BFP was associated with a lower probability to react towards the playback of piglets’ screams ( P < 0.05). However more postural changes after BFP were associated with a higher probability to react towards the playback of piglets’ screams ( P < 0.05). More postural changes during parturition were related with higher piglet BW gain ( P < 0.05), but more postural changes during 12–24 h after BFP were related with lower piglet BW gain ( P < 0.01). No other relationships were detected between pre-partum nesting and maternal behaviour within the 24 h after BFP. High occurrence of pre-partum nesting 4 h before parturition, but not more pre-partum postural changes, may be an early indicator for impaired suckling behaviour and lower weight gain during the first 24 h post-partum. [ABSTRACT FROM AUTHOR]

Dairy calves are often separated from the cow soon after birth and prevented from nursing, but little is known about the effects of nursing on the development of the cow–calf bond. This study evaluated the effect of nursing on affiliative behaviours between the dam and her calf including allogrooming, proximity and latency to reunite after a period of separation. Holstein cow–calf pairs were randomly allocated to three treatments differing only in nutritional dependency on the dam: milk feeder ( n = 10 pairs), combined ( n = 10 pairs) or nursing ( n = 10 pairs). Milk feeder calves could feed ad libitum from an automated milk-feeder, combined calves could suckle from their dams at night and could feed ad libitum from an automated milk feeder and nursing calves could suckle from their dams at night. Cows and calves were kept together during the night (between 20:00 h and 08:00 h) and were housed adjacent to each other during the day (between 08:00 h and 20:00 h). Direct live observations were performed 2 h following the opening of the gate that allowed calves to mix with cows at night. All pairs spent more time (% of observations) allogrooming each other (i.e. own cow/calf) than they did grooming other cows and calves within the same group (10 ± 0.8% vs. 0.4 ± 0.7%, t 29 = 168.8, P < 0.001). The time cow–calf pairs spent allogrooming did not vary with treatment; 10.0 ± 0.8%, F 2, 27 = 0.4, P = 0.696). Similarly, time spent in close proximity without nursing did not differ among treatments; 31 ± 2.6%, F 2, 27 = 0.6, P = 0.543). The percentage of occasions a pair did not reunite (i.e. not observed within 1 m of each other within 3 min) was 23% for the milk feeder pairs, 38% for the combined pairs and 32% for the nursing pairs ( χ 2 = 3.9, P = 0.415). Nevertheless suckling from another cow than own dam was observed at least once by 19 of the 20 calves that were allowed to suckle. Latency to reunite (among pairs that did so within 180 s) was highest for the combined pairs and tended to be lower for milk feeder and nursing calves; 52.5 ± 16.0, 23.3 ± 8.3 and 12.9 ± 5.8; F 2, 24 = 3.1, P = 0.062). These results indicate that dam and calf form a bond independent of nursing. [ABSTRACT FROM AUTHOR]

Sexual conflict theory predicts a trade-off in individual parental care allocated to either current or future reproduction. The optimal amount of current parental effort is expected to differ between adult males and females, with a conflict resolution being reached by negotiation depending on multiple family cues. Currently, a debate exists on how negotiation takes place, along with its potential costs or benefits for all family members. In particular, the specific negotiation rules that male and female parents apply often remain obscure, which in part results from a shortage of empirical studies. We used captive canaries, Serinus canaria , to evaluate consequences of sexual conflict for the offspring by comparing uniparental (female cared for a half clutch) and biparental (both parents cared for a full clutch) families. Our results suggest overall less parental effort in biparental families and offspring were observed to beg harder for parental resources, weigh less as fledglings and tended to grow slower compared to uniparental families. To further increase our understanding of parental negotiation rules, we manipulated the degree of partner visibility and thus information about partner effort by temporarily splitting biparental families. Male and female provisioning strategies depended on both partner visibility and brood demand. An increase in male provisioning was observed after mate removal, whereas the opposite pattern was observed in females. Females, however, increased provisioning in response to offspring begging. We conclude that (1) sexual conflict over parental care is costly for the offspring, (2) sex-specific negotiation rules exist and probably relate to an asymmetry in gathered information and (3) changes in parental feeding strategies trigger a feedback mechanism via brood demand, highlighting the need to consider all family members in order to understand family conflicts and their potential resolution. [ABSTRACT FROM AUTHOR]

Adopting different behavioural strategies may reduce within-group conflict, selecting for behavioural consistency (‘personality’). Personality may also affect grouping tendencies. The relationship between the personality dimensions sociability and boldness nevertheless remains unclear. This knowledge gap may reflect a failure to consider potential trade-offs between avoiding conspecifics, potentially alleviating social stress, and avoiding predation. Furthermore, the effects of personality and state (e.g. body condition or age affecting the costs and benefits of behavioural actions) on cooperativeness should be considered together. This is because state may explain predation vulnerability, which may affect boldness under predation risk, and thus antipredator grouping tendencies. To address the problem, we determined how group size preference and group-forming time depended on boldness (flight initiation distance, FID, in response to an approaching human), body condition and breeding experience in facultatively social eiders, Somateria mollissima , where females form coalitions or care for the young solitarily. Breeding adults and young are subject to high predation pressure, providing a strong incentive for brood-tending females to cooperate. Because hormonal differences may also explain differences in sociability, we included baseline and handling-induced serum corticosterone concentrations of incubating females as potential predictors of sociability. We also statistically controlled for availability of potential partners. The relationship between boldness (FID) and the number of coalition partners ranged from negative (females in poor body condition) to positive (females in good body condition), arguing against a uniform relationship between boldness and sociability. The number of coalition partners decreased with female breeding experience. The time taken to form a coalition was shortest close to the hatching peak in the population. Shyness (long FID) delayed group formation. Despite a need for safety in numbers by shy females in poor body condition, their entry into groups may be constrained by their personality, suggesting a possible trade-off between predator and conspecific avoidance. [ABSTRACT FROM AUTHOR]

Recent research suggests that individuals across a variety of taxa express consistent behavioural differences, or personality, which may affect reproductive success. Most previous studies of avian systems investigated the effects of individual personality on offspring recruitment and other fitness correlates, even in species with biparental care. Here we tested the potential for behavioural similarity within mated pairs of wild eastern bluebirds to impact reproductive success. Specifically, we quantified nest defence behaviour of males and females to address three hypotheses: (1) the individual personality hypothesis, which predicts that individuals with more aggressive personalities will have more nestlings survive to fledging; (2) the pair coordination hypothesis, which predicts similarly behaving pairs will have more nestlings survive to fledging; and (3) the pair intensity hypothesis, which predicts pairs with more aggressive personalities will have more nestlings survive to fledging. Pairs that had similar nest defence strategies produced more fledglings in support of the pair coordination hypothesis. We found no support for either the individual personality hypothesis or the pair intensity hypothesis. Thus, particularly in species with biparental care, it is important to consider the behaviour of both pair members to predict effects on reproductive success. [ABSTRACT FROM AUTHOR]

Although evolutionary theory predicts that parents should discriminate between their own and others' offspring when levels of parental care are large, in some colonial breeding mammals, strong selective pressure would be expected to drive the evolution of mutual recognition between parents and offspring. Although less well studied than parental discrimination, in both birds and mammals, offspring discrimination of parents has also been documented. Nocturnal bats depend heavily on acoustic signals for communication, although little is known about whether bat pups can recognize their mothers based solely on maternal calls. We first investigated whether maternal calls of pomona leaf-nosed bats differ statistically among individuals. Then, we tested whether pups recognize their mothers' calls using a playback experiment. Echolocation pulses and directive calls of mother bats contain enough individual characteristics to allow for individual discrimination. Playback experiments showed that the pups responded with more vocalizations to playback of their own mother's versus another mother's directive calls, but not to playback of their own mother's versus another mother's echolocation pulses, suggesting that offspring can distinguish directive calls, but not echolocation pulses, of their own mother from those of other mothers. To our knowledge, this is the first study in which directive calls from bat mothers have been used to elicit vocalizations from pups and the first study to indicate that pups can recognize their mothers based solely on directive calls. These results advance our understanding of the function of acoustic signals in mother–offspring recognition and the adaptive benefit of such communication, particularly the conditions under which a pup's recognition of its mother is critical. [ABSTRACT FROM AUTHOR]

ABSTRACT The level of dietary protein determines the onset of reproduction, affects offspring growth and maturation, and hence influences life-history traits and fitness. However, to date, the long-term life-history consequences of protein deficiency are not well understood. We studied the transgenerational effects of different levels of dietary protein on the life-history and level of maternal behavior of the striped mouse Rhabdomys dilectus chakae in captivity. Breeding pairs were assigned to three treatments based on the percentage of dietary protein: baseline (BP; 19%); high protein (HP; 24%); and low protein (LP; 10%). Reproductive output and offspring ontogeny was diminished in the LP treatment compared to the other treatments. Transgenerational effects were studied by breeding F2 females raised on the LP or HP diets on the same (HP-HP, LP-LP) or altered diets (HP-LP, LP-HP). The LP-LP treatment had no reproductive success, while reproductive capacity in the remaining treatments was determined mainly by the diet of mothers at breeding. Pups from protein-restricted females (LP, HP-LP) showed post-weaning compensatory growth. Timing of sexual maturity was age-dependent in female and mass-dependent in male offspring. Females fed low protein diets during breeding (LP, HP-LP) displayed lower levels of maternal behavior than females from the other treatments. This study demonstrates that the level of dietary protein influences the life-history of R. d. chakae in predictable ways. The taxon responds to changes in dietary protein at breeding, largely regardless of its nutrition during rearing. Such phenotypic flexibility in life-history parameters allows Rhabdomys to adaptively respond to unpredictable environmental changes. J. Exp. Zool. 323A: 97-108, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Adult-directed predation risk imposes important behavioral constraints on parents and might thus alter relationships between costly sexual ornaments and parental performance. For instance, under low predation risk, highly ornamented individuals might display better parental performance than others, as predicted by 'good parent' models of sexual selection. However, under high risk of predation, highly ornamented individuals might abandon parental effort if conspicuous to predators, or if social partners are more willing to take parental risks when paired with highly ornamented mates. We experimentally elevated perceived adult-directed predation risk near nests to explore how carotenoid- and phaeomelanin-based pigmentation in both sexes relate to parental risk-taking for offspring in the yellow warbler Setophaga petechia. Compared to other males, males with more intense carotenoid-based pigmentation maintained higher levels of paternal effort under predation risk at highly concealed nests, but reduced nestling provisioning rate more at exposed nests. Further, when faced with predation risk, females with more phaeomelanin-based pigmentation reduced nestling provisioning rate less than other females, regardless of nest concealment. Females displayed higher parental effort across treatments when paired to males with more colorful carotenoid pigmentation. However, birds did not reduce parental effort under risk less when paired to a highly ornamented mate, suggesting that predation risk did not accentuate differential allocation. Males did not take fewer parental risks than females. Results indicate that nest concealment modifies parental risk-taking by males with colorful carotenoid-based pigmentation, and suggest that female melanin-based pigmentation may indicate boldness and greater a propensity to take parental risks. [ABSTRACT FROM AUTHOR]

Objectives. To research parental behavior and measure the weight of Nelore and Guzerat calves up to 120 days of age, collecting data from birth up to the first lactation. Materials and methods. Seven different corporal positions were considered to obtain specific data for each of the following categories: time to stand (TP), time to intend to feed after standing (TPTM), weight at birth (PN), weight at 120 days (P120), and time in contact with the calf (TCC). Additionally, independent variables were also evaluated, organized by class: weight at birth (CPN), number of calvings (CNP), order of calving in relation with the herd (CLPR), time of calving (CHP), and finally, hindering to feed (CTAT). Results. There was a significant result in favor of the Nelore race over the Guzerat race. The statistical averages for Nelore and Guzerat were: Time to stand averaged 71 and 153 minutes; time to intend to feed after standing, 39 minutes for Nelore and of 114 minutes for Guzerat. For variable weight at 120 days, Nelore reached an average of 122 kg, and Guzerat 109 kg. For the time in contact with the calf variable there was no significant variance between races. Conclusions. Results showed the superiority of the Nelore race, considering it better adapted to local environmental conditions. [ABSTRACT FROM AUTHOR]

Reproductive efforts are energetically costly and often result in significant trade-offs with other metabolic processes. In many animals, androgens influence how this energy is allocated during the breeding period. In this study, androgen levels of parental bluegill sunfish ( Lepomis macrochirus Rafinesque, 1819) were manipulated by implanting males with either 11-ketotestosterone (11-KT) or flutamide (an androgen receptor antagonist) shortly after spawning. Parental behaviours were assessed for 3 days after implantation. Differential brain gene expression between the two groups was examined using a 44 000 microarray gene chip. We found that 11-KT-implanted males exhibited lower levels of expression of genes related to immune function compared with flutamide-implanted males, suggesting that high androgen levels negatively affect the male immune system. These data thus indicate that a significant trade-off may exist between maintaining high levels of androgens and decreased immune function in parental male bluegill. [ABSTRACT FROM AUTHOR]

Male rodents behave differently toward pups because of different sexual and/or paternal experiences; however, the mechanisms underlying these responses are not well understood. Using socially monogamous mandarin voles ( Microtus mandarinus ) we investigated the behavioral responses of males with different reproductive experiences (virgin males, paired males and new fathers) to new born pups. Central levels of neuropeptide oxytocin (OT), tyrosine hydroxylase (TH), as well as oxytocin receptor (OTR), dopamine 1-type receptor (D1R) and dopamine 2-type receptor (D2R) mRNA expression in the nucleus accumbens and medial amygdala were also measured in these males. Our data showed that new fathers exhibited more approaching behavior and contained more OT-immunoreactive and TH-immunoreactive neurons. In addition to increased OTR mRNA expression in the nucleus accumbens and medial amygdala, new fathers had higher D1R and D2R mRNA expression in the nucleus accumbens, and less D1R and D2R mRNA expression in the medial amygdala than paired males. These results demonstrate that males with different reproductive experiences display different behavioral responses to pups and that these differences are associated with altered OT and dopamine, and their receptors in specific brain regions. [ABSTRACT FROM AUTHOR]

One of the strongest predictors of healthy child development is the quality of maternal care. Although many measures of observation and self-report exist in humans to assess global aspects of maternal care, such qualitative measures are lacking in nonhuman primates. In this study, we developed an instrument to measure global aspects of maternal care in rhesus monkeys, with the goal of complementing the individual behavioral data collected using a well-established rhesus macaque ethogram during the first months postpartum. The 22 items of the instrument were adapted from human maternal sensitivity assessments and a maternal Q-sort instrument already published for macaques. The 22 items formed four dimensions with high levels of internal reliability that represented major constructs of maternal care: (1) Sensitivity/Responsivity, (2) Protectiveness, (3) Permissiveness, and (4) Irritability. These dimensions yielded high construct validity when correlated with mother-infant frequency and duration behavior that was collected from focal observations across the first 3 postnatal months. In addition, comparisons of two groups of mothers (Maltreating vs. Competent mothers) showed significant differences across the dimensions suggesting that this instrument has strong concurrent validity, even after controlling for focal observation variables that have been previously shown to significantly differentiate these groups. Our findings suggest that this Instrument of Macaque Maternal Care has the potential to capture global aspects of the mother-infant relationship that complement individual behaviors collected through focal observations. Am. J. Primatol. 77:20-33, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background. Intra cohort cannibalism is one of the main factors that affects the growth and survival of cultured fishes, especially in the larval and juvenile stages. Cannibalism is mainly influenced by extrinsic factors, but intrinsic effects cannot be excluded. As regards the family Percidae, all-female rearing can be advantageous for the fish growth, but does this solution have some impact on cannibalism? The main objective of this study was to investigate potential differences in cannibalism rate and its relation to further growth and survival between mixed-sex and all-female Eurasian perch, Perca fluviatilis Linnaeus, 1758, larvae reared in full-siblings and half-siblings groups. The additional purpose of this study was to determine whether there was some maternal influence on the cannibalism-survival-growth dynamics in cultured Eurasian perch larvae. Materials and Methods. Cannibalism, survival, and growth were studied in mixed-sex and all-female progenies of Eurasian perch larvae. Ten-day old larvae (body weight of 20 mg) originating from the crosses of four parents (two females: f1 and f2; one male: ma; and one neomale: mc) were reared over 77 days at 22°C under the light regime of 16 : 8 (light : dark) in replicated groups consisting of mixed-sex full siblings (f1ma, f2ma), all-female full siblings (f1mc, f2mc), or mixed-sex half-siblings (f1ma + f2ma) and all-female groups (f1mc + f2mc). Results. At the end of the experiment, there was no sexual growth dimorphism and no sex-biased cannibalism. Neither the effect of sibling versus half-sibling groups, nor effects of normal progeny versus all-female population on survival and cannibalism rate were significant. By contrast, maternal effects on cannibalism were observed, chiefly as regards type I cannibalism (partial and tail-first ingestion), and they impacted on survival, as mortality from other causes (complete cannibalism or others) was independent from maternal origin. Conclusion. There is no particular disadvantage of rearing monosex female progenies in term of cannibalism and survival, whereas this culture-management solution is prone to produce long-term advantages for the perch growth, owing to the faster growth of female fish. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyl (PCB) is a persistent organic pollutant known to induce diverse molecular and behavioral alterations. Effects of PCB exposure could be transmitted to future generations via changes in behavior and gene expression. Previous work has shown that PCB-exposure can alter social behavior. The present study extends this work by examining a possible molecular mechanism for these changes. Pregnant rats (Sprague-Dawley) were exposed through diet to a combination of non-coplanar (PCB 47 - 2,20,4,40-tetrachlorobiphenyl) and coplanar (PCB 77 - 3,30,4,40- tetrachlorobiphenyl) congeners. Maternal care behaviors were examined by evaluating the rate and quality of nest building on the last 4 d of gestation and dam/pup interactions on postnatal days 1, 2, 4 and 6. On postnatal day 17, dams were euthanized and hypothalamic tissue was removed for expression analyses of the oxytocin receptor (OXTR) and cytochrome P450 1a1 (Cyp1a1). PCB altered nest building and maternal care behaviors. Specifically, there was a significant increase in time spent in low crouch and high crouch nursing posture on PND 4 and PND 6 respectively. Molecular analysis revealed that PCB exposure upregulated OXTR expression in the hypothalamus of dams. These results provide a possible molecular mechanism for PCB-induced changes in social interactions during early development. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Investigaciones Veterinarias del Peru is the property of Universidad Nacional Mayor de San Marcos (UNMSM) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Investigaciones Veterinarias del Peru is the property of Universidad Nacional Mayor de San Marcos (UNMSM) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)