Reproductive behaviour and fertilized spawns in cultured Solea senegalensis broodstock co-housed with wild breeders during their juvenile stages

The reproductive failure of Senegalese sole (Solea senegalensis) cultured males (reared entirely in captivity from egg through to adult) that do not participate in reproductive behaviours to fertilise spawns, results in a problem to achieve reproductive control in captivity. However, cohabitation with wild males has led to an increase in the involvement of cultured males in reproductive behaviour, although their contribution to fertilised spawning is still lower than that of wild breeders. This study aimed to examine the effect of different social conditions, on the reproductive behaviour and spawning success of cultured breeders over three reproductive seasons. Before starting this study, different social learning opportunities were provided to the breeders from the juvenile to the pubertal stages of the individuals. Behaviour and spawning were evaluated in four experimental groups of cultured breeders: two groups (W1 and W2) that prior to this study were reared during the juvenile stage with wild breeders that fertilized spawns, a Culture breeder group (CB) that was previously reared with cultured breeders that spawned unfertile eggs, and a negative control group (CN) that was reared in isolation from adult fish. During the three reproductive seasons, spawning was obtained from all groups. Generally, the first year had the highest egg production and the third year the lowest. However, fertilised eggs were only obtained from W1 in the first year. A total of eight fertilised spawns were collected with a fertilisation rate of 28.02 ± 13.80 % and a hatching rate of 15.04 ± 10.40 %. The mean number of larvae obtained per spawn was 7,683 ± 5,947 and the total number of larvae from all eight spawns was 61,468. The paternity analysis assigned 64.3 % of larvae to a single couple of breeders, while 34.3 % of larvae were not assigned to any single family, but inconclusively to more than three parents. The highest locomotor activity was observed in W1, while no significant differences were observed in the number of movements within W2, CB and CN. In all groups, during the peak of locomotor activity (19h00-20h00), the main reproductive behaviours observed were Rest the Head and Follow, while the Guardian behaviour was low and Coupled behaviour was only observed in W1. Over time, the reproductive behaviours decreased, except for Follow. The social learning opportunities provided by cohabitation with wild fish during juvenile stages prior to spawning in W1, increased activity and fertilised spawning. However, the number of successful spawns was low and over time stopped in association with a decrease in reproductive behaviour. This suggests that other mechanisms of behavioural learning could be involved in reproductive success, such as reproductive dominance, environmental conditions or hormonal interactions that could affect physiological processes in the reproduction of captive breeders.

Mate calling alters expression of neuropeptide, cocaine- and amphetamine- regulated transcript (CART) in the brain of male frog Microhyla nilphamariensis

Croaking is a unique component of reproductive behaviour in amphibians which plays a key role in intraspecies communication and mate evaluation. While gonadal hormones are known to induce croaking, central regulation of sound production is less studied. Croaking is a dramatic, transient activity that sets apart an animal from non-croaking individuals. Herein, we aim at examining the profile of the neuropeptide cocaine- and amphetamine-regulated transcript (CART) in actively croaking and non-croaking frog Microhyla nilphamariensis. In anurans, this peptide is widely expressed in the areas inclusive of acoustical nuclei as well as areas relevant to reproduction. CART immunoreactivity was far more in the preoptic area (POA), anteroventral tegmentum (AV), ventral hypothalamus (vHy), pineal (P) and pituitary gland of croaking frog compared to non-croaking animals. On similar lines, tissue fragments collected from the mid region of the brain inclusive of POA, vHy, AV, pineal and pituitary gland of croaking frog showed upregulation of CART mRNA. However, CART immunoreactivity in the neuronal perikarya of raphe (Ra) was completely abolished during croaking activity. The data suggest that CART signaling in the brain may be an important player in mediating croaking behaviour in the frog.

How aggressive interactions with biomimetic agents optimize reproductive performances in mass-reared males of the Mediterranean fruit fly

Mass-rearing procedures of insect species, often used in biological control and Sterile Insect Technique, can reduce the insects competitiveness in foraging, dispersal, and mating. The evocation of certain behaviours responsible to induce specific neuroendocrine products may restore or improve the competitiveness of mass-reared individuals. Herein, we used a mass-reared strain of Ceratitis capitata as model organism. C. capitata is a polyphagous pest exhibiting territorial displays that are closely related to its reproductive performance. We tested if the behaviour of C. capitata males could be altered by hybrid aggressive interactions with a conspecific-mimicking robotic fly, leading to more competitive individuals in subsequent mating events. Aggressive interactions with the robotic fly had a notable effect on subsequent courtship and mating sequences of males that performed longer courtship displays compared to naïve individuals. Furthermore, previous interactions with the robotic fly produced a higher mating success of males. Reproductive performances of C. capitata males may be improved by specific octopaminergic neurones activated during previous aggressive interactions with the robotic fly. This study adds fundamental knowledge on the potential role of specific neuro-behavioural processes in the ecology of tephritid species and paves the way to innovative biotechnological control methods based on robotics and bionics.

Diverse environmental cues drive the size of reproductive aggregation in a rheophilic fish

BACKGROUND

Animal migrations are periodic and relatively predictable events, and their precise timing is essential to the reproductive success. Despite large scientific effort in monitoring animal reproductive phenology, identification of complex environmental cues that determine the timing of reproductive migrations and temporal changes in the size of reproductive aggregations in relation to environmental variables is relatively rare in the current scientific literature.

METHODS

We tagged and tracked 1702 individuals of asp (Leuciscus aspius), a large minnow species, and monitored with a resolution of one hour the size of their reproductive aggregations (counts of sexes present at the breeding grounds standardized by the sum of individuals in the season) over seven breeding seasons using passive integrated transponder tag systems. We examined the size of reproductive aggregations in relation to environmental cues of day number within a reproductive season (intra-year seasonality), water temperature, discharge, hour in a day (intra-day pattern), temperature difference between water and air, precipitation, atmospheric pressure, wind speed and lunar phase. A generalized additive model integrating evidence from seven breeding seasons and providing typical dynamics of reproductive aggregations was constructed.

RESULTS

We demonstrated that all environmental cues considered contributed to the changes in the size of reproductive aggregations during breeding season, and that some effects varied during breeding season. Our model explained approximately 50% of the variability in the data and the effects were sex-dependent (models of the same structure were fitted to each sex separately, so that we effectively stratified on sex). The size of reproductive aggregations increased unimodally in response to day in season, correlated positively with water temperature and wind speed, was highest before and after the full moon, and highest at night (interacting with day in a season). Males responded negatively and females positively to increase in atmospheric pressure.

CONCLUSION

The data demonstrate complex utilization of available environmental cues to time reproductive aggregations in freshwater fish and their interactions during the reproductive season. The study highlights the need to acquire diverse data sets consisting of many environmental cues to achieve high accuracy of interpretation of reproductive timing.

Patients' and providers' perspectives on non-urgent egg freezing decision-making: a thematic analysis

BACKGROUND

The decision to undergo non-urgent egg freezing (EF) is complex for patients and providers supporting them. Though prior studies have explored patient perspectives, no study has also included the separate perspectives of providers.

METHODS

This qualitative study involved semi-structured individual interviews exploring the decision to undergo EF. Participants included patients considering EF at one academic fertility clinic and providers who counsel patients about EF from across Canada. Data analysis was accomplished using thematic analysis. Data saturation was met after interviewing 13 providers and 12 patients.

FINDINGS

Four themes were identified and explored, illuminating ways in which patients and providers navigate decision-making around EF: (1) patients viewed EF as a 'back-up plan' for delaying the decision about whether to have children, while providers were hesitant to present EF in this way given the uncertainty of success; (2) providers viewed ovarian reserve testing as essential while patients believed it unnecessarily complicated the decision; (3) patients and providers cited a need for change in broader societal attitudes regarding EF since social stigma was a significant barrier to decision-making; and (4) commonality and peer support were desired by patients to assist in their decision, although some providers were hesitant to recommend this to patients.

CONCLUSIONS

In conclusion, the decision to undergo EF is complex and individual patient values play a significant role. In some areas, there is disconnect between providers and patients in their views on how to navigate EF decision-making, and these should be addressed in discussions between providers and patients to improve shared decision-making.

A Smaller Habenula is Associated with Increasing Intensity of Sexual Selection

The habenula is a small structure in the brain that acts as a relay station for neural information, helping to modulate behaviour in response to variable and unpredictable stimuli. Broadly, it is evolutionarily conserved in structure and connectivity across vertebrates and is the most prominent bilaterally asymmetric structure in the brain. Nonetheless, comparative evolutionary studies of the habenula are virtually non-existent. Here, we examine the volumes of the medial and lateral habenular subregions, in both hemispheres, across a group of Australian agamid lizards in the genus Ctenophorus. In males, we found bilaterally asymmetrical selection on the lateral habenula to become smaller with increasing intensity of sexual selection, possibly as a mechanism to increase aggressive responses. In females, we found bilaterally symmetrical selection on both the medial and lateral subregions to become smaller with increasing sexual selection. This is consistent with sexual selection increasing motivation to reproduce and the habenula's well-characterized role in controlling and modifying responses to rewarding stimuli. However, as there are currently no studies addressing habenular function in reptiles, it is difficult to draw more precise conclusions. As has happened recently in biomedical neuroscience, it is time for the habenula to receive greater attention in evolutionary neuroscience.

Cyclooxygenases of ovoviviparous black rockfish (Sebastes schlegelii): Cloning, tissue distribution and potential role in mating and parturition

Prostaglandins are a series of unsaturated fatty acids that play critical roles in regulating reproductive events. The prostaglandins endoperoxide H synthases-1/2 (PGHS-1/2; also named cyclooxygenases-1/2, COX-1/2) catalyse the commitment step in prostaglandin synthesis. However, the of the cox genes in teleosts, especially ovoviviparous teleosts, is still unclear. The aim of the present study was to determine the potential role of cox genes in mating and parturition behaviour using black rockfish (Sebastes schlegelii) as a model species. Two transcripts, cox1 and cox2, were cloned. The phylogenetic analysis results revealed that both cox genes were closely related to mammalian coxs. qPCR analyses of their tissue distribution showed that cox1 was mainly expressed in the heart in both sexes, while cox2 was mainly expressed in the testis and ovary. Detection of cox expression in samples from reproductive-related stages further showed that both cox genes may play important roles in mating and parturition processes. In situ hybridization further detected positive cox mRNA signals in the testis and ovary, where they are known to be involved in mating and parturition behaviour. These data suggest that cox1 and cox2 are crucial in inducing mating, gonad regeneration and parturition behaviour.

Kisspeptin modulates gamma-aminobutyric acid levels in the human brain

Gamma-aminobutyric acid (GABA) is a key inhibitory neurotransmitter that has been implicated in the aetiology of common mood and behavioural disorders. By employing proton magnetic resonance spectroscopy in man, we demonstrate that administration of the reproductive neuropeptide, kisspeptin, robustly decreases GABA levels in the limbic system of the human brain; specifically the anterior cingulate cortex (ACC). This finding defines a novel kisspeptin-activated GABA pathway in man, and provides important mechanistic insights into the mood and behaviour-altering effects of kisspeptin seen in rodents and humans. In addition, this work has therapeutic implications as it identifies GABA-signalling as a potential target for the escalating development of kisspeptin-based therapies for common reproductive disorders of body and mind.

The influence of physiological status on the reproductive behaviour of humpback whales (Megaptera novaeangliae)

For most cetacean species, there is little known about how an individual's physiology influences its behaviour. Humpback whales (Megaptera novaeangliae) are a good candidate to examine such links as they have a well-described distribution and behaviour, can be consistently sampled using remote biopsy systems, and have been the subject of several previous endocrine studies. The objective here was to examine whether a female humpback whale's social state (i.e. escorted by a male or not) is related to her endocrine condition, and whether male dominance ranking is related to testosterone levels. Skin and blubber biopsies were collected from the east and west Australian humpback whale populations in 2010-2016 (n = 252) at multiple times throughout the winter-spring breeding season. Steroid hormones were extracted from blubber and concentrations of progesterone (a marker for pregnancy), testosterone (a marker of male testicular activity) and oestradiol (a potential marker of ovarian activity) measured using enzyme-immunoassays. Principal escorts-the dominant males in mixed sex groups-had significantly higher blubber testosterone levels (mean ± SE; 1.43 ± 0.20 ng/g wet weight) than subordinate, secondary escorts (0.69 ± 0.06 ng/g wet weight). Females that were escorted by males typically possessed elevated blubber oestradiol levels (1.96 ± 0.25 ng/g wet weight; p = 0.014); few were considered to be pregnant (p = 0.083). 'Unescorted' females displayed characteristically lower blubber oestradiol levels (0.56 ± 0.06 ng/g wet weight). Together, these results are consistent with 'challenge hypothesis' theory and suggest the existence of associated reproductive patterns in humpback whales.

Investigating parental care behaviour in same-sex pairing of zoo greater flamingo (Phoenicopterus roseus)

Same-sex pair bonds have been documented in several animal species and they are widespread in birds. However, little is known about the evolutionary origin and the adaptive value of such behaviour. The aim of this study was to investigate the parental behaviour of four zoo female greater flamingos involved in two breeding pairs, housed in a flock at Parco Natura Viva, Italy. Further, the behaviour of the study females was compared with that of male and female flamingos in heterosexual pairs described in a previous published work on this same flock. For each pair, the behaviour of both birds during the incubation period was recorded and twenty 10-minute sessions were run within the incubation period. A continuous focal animal sampling method was used to collect data on location (on the nest or not on the nest) and the parental care behaviour (e.g.: agonistic behaviours toward disturbing conspecifics, egg-care, nest-building, self-comfort behaviour, sleeping) of the two pairs. Data of the current study females were compared with those of females and males involved in heterosexual pairs of this same flock. Results showed that within each pair the egg-layer female stayed away from the nest more than the other female. In addition, the female that did not lay an egg was more involved in agonistic behaviour compared to other females, particularly when in specific locations. In heterosexual pairs, male flamingos were more involved in the incubation and in nest protection. Moreover, no significant differences in the time spent on the nest and away from the nest between the heterosexual male and the non-layer females of same-sex pairs were found. The same findings were reported when comparing heterosexual females and the egg-layer females of the same-sex pairs. Therefore, our findings suggest that in greater flamingos the behaviour of the female–female pairs seems to be equivalent to that of male-female bonds. Such research provides more insight into flamingo social behaviour, and their reproductive cycle, and provides information on why pair bonds may form and how these affect the wider breeding behaviour of the flock.

The antidepressant fluoxetine alters mechanisms of pre- and post-copulatory sexual selection in the eastern mosquitofish (Gambusia holbrooki)

Contamination of aquatic habitats with pharmaceuticals is a major environmental concern. Recent studies have detected pharmaceutical pollutants in a wide array of ecosystems and organisms, with many of these contaminants being highly resistant to biodegradation and capable of eliciting sub-lethal effects in non-target species. One such pollutant is fluoxetine, a widely prescribed antidepressant, which is frequently detected in surface waters globally and can alter physiology and behaviour in aquatic organisms. Despite this, relatively little is known about the potential for fluoxetine to disrupt mechanisms of sexual selection. Here, we investigate the impacts of 30-day exposure to two environmentally realistic levels of fluoxetine (low and high) on mechanisms of pre- and post-copulatory sexual selection in the eastern mosquitofish (Gambusia holbrooki). We tested 1) male mating behaviour in the absence or presence of a competitor male, and 2) sperm quality and quantity. We found that high-fluoxetine exposure increased male copulatory behaviour in the absence of a competitor, while no effect was detected under male-male competition. Further, fluoxetine exposure at both concentrations increased total sperm count relative to males from the control group, while no significant change in sperm quality was observed. Lastly, low-fluoxetine males showed a significant reduction in condition index (mass relative to length). Our study is the first to show altered mechanisms of both pre- and post-copulatory sexual selection in an aquatic species resulting from environmentally realistic fluoxetine exposure, highlighting the capacity of pharmaceutical pollution to interfere with sensitive reproductive processes in wildlife.

Predicting the Influence of Streamflow on Migration and Spawning of a Threatened Diadromous Fish, the Australian Grayling Prototroctes Maraena

The development of effective strategies to restore the biological functioning of aquatic ecosystems with altered flow regimes requires a detailed understanding of flow-ecology requirements, which is unfortunately lacking in many cases. By understanding the flow conditions required to initiate critical life history events such as migration and spawning, it is possible to mitigate the threats posed by regulated river flow by providing targeted environmental flow releases from impoundments. In this study, we examined the influence of hydrological variables (e.g., flow magnitude), temporal variables (e.g., day of year) and spatial variables (e.g., longitudinal position of fish) on two key life history events (migration to spawning grounds and spawning activity) for a threatened diadromous fish (Australian grayling Prototroctes maraena) using data collected from 2008 to 2015 in the Bunyip-Tarago river system in Victoria. Our analyses revealed that flow changes act as a cue to downstream migration, but movement responses differed spatially: fish in the upper catchment showed a more specific requirement for rising discharge to initiate migration than fish in the lower catchment. Egg concentrations peaked in May when weekly flows increased relative to the median flow during a given spawning period. This information has recently been incorporated into the development of targeted environmental flows to facilitate migration and spawning by Australian grayling in the Bunyip-Tarago river system and other coastal systems in Victoria.

Extra-pair parentage and personality in a cooperatively breeding bird

ABSTRACT

Why so much variation in extra-pair parentage occurs within and among populations remains unclear. Often the fitness costs and benefits of extra-pair parentage are hypothesised to explain its occurrence; therefore, linking extra-pair parentage with traits such as personality (behavioural traits that can be heritable and affect reproductive behaviour) may help our understanding. Here, we investigate whether reproductive outcomes and success are associated with exploratory behaviour in a natural population of cooperatively breeding Seychelles warblers (Acrocephalus sechellensis) on Cousin Island. Exploratory behaviour correlates positively with traits such as risk-taking behaviour and activity in other wild bird species and might promote extra-pair mating by increasing the rate at which potential extra-pair partners are encountered. We therefore predicted that fast-exploring individuals would have more extra-pair offspring. There is also a potential trade-off between pursuing extra-pair parentage and mate guarding in males. We therefore also predicted that fast-exploring males would be more likely to pursue extra-pair parentage and that this would increase the propensity of their mate to gain extra-pair parentage. We found that neither the total number of offspring nor the number of extra-pair offspring were associated with a male's or female's exploratory behaviour. However, there was a small but significant propensity for females to have extra-pair fertilisations in pairs that were behaviourally disassortative. Overall, we conclude that, due to the small effect size, the association between exploratory behaviour and extra-pair paternity is unlikely to be biologically relevant.

SIGNIFICANCE STATEMENT

True genetic monogamy is rare, even in socially monogamous systems, and multiple factors, such as behaviour, social structure, morphology and physiology, determined by the biological system can cause variation in extra-pair parentage (EPP). Therefore, investigating the inherent differences in these factors among individuals could be informative. We investigated whether reproductive outcomes/success are associated with differences in the propensity to explore novel environments/objects in a promiscuous, island-dwelling cooperatively breeding bird, the Seychelles warbler. Our results showed that exploratory behaviour was not associated with the number of offspring produced by an individual, and thus the long-term fitness consequences of different exploratory tendencies did not differ. We also found that the propensity to engage in EPP in females was higher in dissimilar behavioural pairs, but due to the small effect size, we hesitate to conclude that there are personality-dependent mating outcomes in the population.

Emerging Roles of Kisspeptin in Sexual and Emotional Brain Processing

The emergence of kisspeptin as a crucial regulator of the hypothalamo-pituitary-gonadal (HPG) axis over the last 14 years has answered many questions as to the control of reproductive hormone secretion from the hypothalamus. More recently, the role of kisspeptin outside the HPG axis has received increasing attention in the hope of delineating the pathways linking various sensory and social behaviours to reproduction. These studies, in a range of species from zebrafish to humans, have identified a role for kisspeptin in behavioural networks related to reproduction including olfaction, audition, fear, anxiety, mood, and sexual arousal. The available evidence suggests that extrahypothalamic kisspeptin signalling encourages positive aspects of emotional and sexual brain processing in a presumed drive towards reproduction and ultimately maintenance of the species at a population level. In this review, we examine these studies, which collectively propose that kisspeptin may integrate sexual and emotional brain processing with the control of the HPG axis.

The sexual preference of female rats is influenced by males' adolescent social stress history and social status

Ongoing development of brain systems for social behaviour renders these systems susceptible to the influence of stressors in adolescence. We previously found that adult male rats that underwent social instability stress (SS) in mid-adolescence had decreased sexual performance compared with control males (CTL). Here, we test the hypotheses that SS in adolescence decreases the "attractiveness" of male rats as sexual partners compared with CTL rats and that dominance status is a protective factor against the effects of SS. The main prediction was that females would spend more time with CTL males than SS males, and that this bias would be greater for submissive than for dominant rats. Among dominant pairs (n=16), females preferred SS males, spending more time with and visiting more often SS than CTL males (each pair tested 5×), and SS males had shorter latencies to ejaculation, shorter inter-ejaculation intervals, and made more ejaculations compared with CTL males. Among submissive pairs (n=16), females spent more time with, visited more often, and displayed more paracopulatory behaviour with CTL than with SS males, and differences in sexual performance between SS and CTL males were modest and in the opposite direction from that in dominant pairs. The heightened motivation of SS males relative to CTL males for natural rewards may have attenuated differences in sexual performance in a paced mating context. In sum, the experience of stress in adolescence leads to long-lasting changes in males that are perceptible to females, are moderated by social status, and influence sexual behaviour.

Risk Factors of Female Breast Cancer in Vietnam: A Case-Control Study

Purpose

Rates of women with breast cancer have increased rapidly in recent years in Vietnam, with over 10,000 new patients contracting the disease every year. This study was conducted to identify demographic, reproductive and lifestyle risk factors for breast cancer in Vietnam.

Materials and Methods

Breast density, demographic, reproductive and lifestyle data of 269 women with breast cancer and 519 age-matched controls were collected in the two largest oncology hospitals in Vietnam (one in the north and one in the south). Baseline differences between cases and controls in all women, premenopausal and postmenopausal women were assessed using chi-squared tests and independent t tests. Conditional logistic regression was used to derive odds ratios (OR) for factors that had statistically significant associations with breast cancer.

Results

Vietnamese women with breast cancer were significantly more likely to have a breast density > 75% (OR, 1.7), be younger than 14 years at first menstrual period (OR, 2.2), be postmenopausal (OR, 2.0), have less than three pregnancies (OR, 2.1), and have less than two babies (OR, 1.7). High breast density (OR, 1.6), early age at first menstrual period (OR, 2.6), low number of pregnancies (OR, 2.3), hormone use (OR, 1.8), and no physical activities (OR, 2.2) were significantly associated with breast cancer among premenopausal women, while breast density (OR, 2.0), age at first menstrual period (OR, 1.8), number of pregnancies (OR, 2.3), and number of live births (OR, 2.4) were the risk factors for postmenopausal women.

Conclusion

Breast density, age at first menarche, menopause status, number of pregnancies, number of babies born, hormone use and physical activities were significantly associated with breast cancer in Vietnamese women.

Who Delays Childbearing? The Associations Between Time to First Birth, Personality Traits and Education

Using data from a large-scale survey, the British Household Panel Survey, this paper assesses the influence of personality traits on the timing of first childbirth and investigates whether, and in what way, personality traits explain the differences in maternity timing across educational groups. We estimate a log-logistic model of the time to first childbirth and show that there is a statistically significant relationship between the Big Five personality traits and the timing of motherhood. The results also show that highly qualified women who are 'open-minded' have the lowest hazards of childbirth, lower than similar less educated counterparts.

Experiences of termination of pregnancy for a fetal anomaly: A qualitative study of virtual community messages

OBJECTIVE

to explore experiences described by posters in Swedish virtual communities before, during and after termination of pregnancy due to a fetal anomaly.

DESIGN

cross-sectional qualitative study of messages in virtual communities. The messages were purposefully selected in 2014 and analyzed with inductive qualitative manifest content analysis.

SETTING

two large and active Swedish virtual communities.

SAMPLE

1623 messages from 122 posters (112 females, 1 male, and 9 did not disclose their sex), written between 2008 and 2014. The majority of the posters were females (91%) with recent experience of termination of pregnancy following different prenatal diagnoses (63% less than one year since the termination).

MEASUREMENTS AND FINDINGS

before the termination, posters experienced an emotional shock and a difficult decision. During the termination, they needed compassionate care from present caregivers, experienced intense emotional and physical pain, lacked an understanding about the abortion, and expressed varied feelings about the option to view the fetus. After the termination, posters used different strategies to come to terms with and accept the decision, experienced a perinatal loss, expressed fears of recurrence, and longed for a new child.

KEY CONCLUSIONS

spanning across the time before, during and after the abortion, women who terminate a pregnancy due to a fetal anomaly express considerable physical and emotional pain, with psychosocial and reproductive consequences.

IMPLICATIONS FOR PRACTICE

information and preparation, including the decision whether or not to view the fetus, are important aspects to consider when caring for individuals who have decided to terminate a pregnancy for a fetal anomaly. The findings indicate a need for structures that offer support to women who suffer from fears of recurrence in future pregnancies.

The sterile male technique: irradiation negatively affects male fertility but not male courtship

The sterile male technique is a common method to assign paternity, widely adopted due to its relative simplicity and low cost. Male sterility is induced by exposure to sub lethal doses of chemosterilants or irradiation, the dosage of which has to be calibrated for every species to provide successful male sterilisation, without affecting male physiology and behaviour. While the physiological effects of sterilisation are usually assessed for each study, the behavioural ones are rarely analysed in detail. Using the orb web spider Argiope keyserlingi as a model we first tested (1) the validity of the thread assay, which simulates male courtship behaviour in a standardised context, as a proxy representing courtship on a female web. We then investigated (2) the effectiveness of male sterilisation via irradiation and (3) its consequences on male courtship behaviour. Our results validate the thread assay and the sterile male technique as legitimate tools for the study of male courtship behaviour and fertilisation success. We show that these techniques are time and cost effective and reduce undesirable variation, thereby creating opportunities to study and understand the mechanisms underlying sexual selection.

Sex in troubled waters: Widespread agricultural contaminant disrupts reproductive behaviour in fish

Chemical pollution is a pervasive and insidious agent of environmental change. One class of chemical pollutant threatening ecosystems globally is the endocrine disrupting chemicals (EDCs). The capacity of EDCs to disrupt development and reproduction is well established, but their effects on behaviour have received far less attention. Here, we investigate the impact of a widespread androgenic EDC on reproductive behaviour in the guppy, Poecilia reticulata. We found that short-term exposure of male guppies to an environmentally relevant concentration of 17β-trenbolone-a common environmental pollutant associated with livestock production-influenced the amount of male courtship and forced copulatory behaviour (sneaking) performed toward females, as well as the receptivity of females toward exposed males. Exposure to 17β-trenbolone was also associated with greater male mass. However, no effect of female exposure to 17β-trenbolone was detected on female reproductive behaviour, indicating sex-specific vulnerability at this dosage. Our study is the first to show altered male reproductive behaviour following exposure to an environmentally realistic concentration of 17β-trenbolone, demonstrating the possibility of widespread disruption of mating systems of aquatic organisms by common agricultural contaminants.

Male and female breeding strategies in a cooperative primate

Marmosets are cooperative breeders organized as extended family groups, but breeding is generally restricted to a single pair. Breeding competition is fierce in female marmosets; males, on the other hand, show low levels of intragroup aggression. We investigated male and female breeding strategies and the resulting reproductive output in 9 wild groups. Reproductive output, tenure of breeding animals, identification of the breeding system, breeding position replacements, migration and infanticide were recorded; also, we recorded grooming and aggression. Replacement of the breeding male or female was observed on nine occasions. On four occasions, the son of the breeding male inherited the breeding post, but we never observed inheritance of a breeding post by a daughter. Mostly, females attained a breeding post by immigrating to a group that had a breeding vacancy. Our results showed that Callithrix jacchus males and females use different strategies to attain a breeding position and maintain it for as long as possible. These strategies prolong the tenure of the breeding position, which is the best way to produce a large number of offspring. This article is part of a Special Issue entitled: Neotropical Behaviour.

Out of sight but not out of harm's way: Human disturbance reduces reproductive success of a cavity-nesting seabird

While negative effects of human disturbance on animals living above the ground have been widely reported, few studies have considered effects on animals occupying cavities or burrows underground. It is generally assumed that, in the absence of direct visual contact, such species are less vulnerable to disturbance. Seabird colonies can support large populations of burrow- and cavity-nesting species and attract increasing numbers of tourists. We investigated the potential effects of recreational disturbance on the reproductive behaviour of the European storm petrel Hydrobates pelagicus, a nocturnally-active cavity-nesting seabird. Reproductive phenology and outcome of nests subject to high and low levels of visitor pressure were recorded in two consecutive years. Hatching success did not differ between disturbance levels, but overall nestling mortality was significantly higher in areas exposed to high visitor pressure. Although visitor numbers were consistent throughout the season, the magnitude and rate of a seasonal decline in productivity were significantly greater in nests subject to high disturbance. This study presents good evidence that, even when humans do not pose a direct mortality risk, animals may perceive them as a predation risk. This has implications for the conservation and management of a diverse range of burrow- and cavity-dwelling animals. Despite this reduction in individual fitness, overall colony productivity was reduced by ⩽1.6% compared with that expected in the absence of visitors. While the colony-level consequences at the site in question may be considered minor, conservation managers must evaluate the trade-off between potential costs and benefits of public access on a site- and species-specific basis.

Altered reproductive behaviours in male mosquitofish living downstream from a sewage treatment plant

Freshwater environments are common repositories for the discharge of large volumes of domestic and industrial waste, particularly through wastewater effluent. One common group of chemical pollutants present in wastewater are endocrine disrupting chemicals (EDCs), which can induce morphological and behavioural changes in aquatic organisms. The aim of this study was to compare the reproductive behaviour and morphology of a freshwater fish, the mosquitofish (Gambusia holbrooki), collected from two sites (wastewater treatment plant (WWTP) and a putative pristine site). The mosquitofish is a sexually dimorphic livebearer with a coercive mating system. Males inseminate females using their modified anal fin as an intromittent organ. Despite this, females are able to exert some control over the success of male mating attempts by selectively associating with, or avoiding, certain males over others. Using standard laboratory assays of reproductive behaviour, we found that mosquitofish males living in close proximity to WWTP showed increased mating activity compared to those inhabiting a pristine site. More specifically, during behavioural trials in which males were allowed to interact with females separated by a transparent divider, we found that WWTP-males spent more time associating with females. Concordant with this, when males and females were subsequently allowed to interact freely, WWTP-males also spent more time chasing and orienting towards the females. As a result, females from both sites showed more interest towards the WWTP-site males. Male anal fin morphology, however, did not differ between sites. Our study illustrates that lifetime exposure to WWTP-effluents can greatly affect male behaviour. The results underscore the importance of behaviour as a potential tool for investigating unknown contaminants in the environment.

Estrogenic chemical effects are independent from the degree of sex role reversal in pipefish

Endocrine disrupting chemicals (EDCs) have been reported to disturb several ecological relevant endpoints. Surprisingly, EDC-induced effects on fish sexual behaviour have been poorly studied despite the fact that even subtle alterations might contribute to a disruption of sexual interactions, thus negatively impacting reproduction. As the few assessments on sexual behaviour have been conducted in species with orthodox sex roles, it might be argued that sex-role reversed species might provide a potentially complementary system to further explore the effects of EDCs on reproduction. In the present study, two pipefish species with distinct degrees of sex-role reversal were selected to further elucidate the impact of chronic EE2 exposure on sexual behaviour and reproduction-related endpoints. The obtained results indicate that, independently of the degree of sex role reversal, courtship behaviour seems to resist oestrogenic chemical exposure. However, exposure to environmentally relevant EE2 levels did induce a complete absence of pregnancies at 18 ng/L. Even though pregnancies were observed at intermediate concentrations, the percentage of non-transferred or misplaced oocytes increased and a dose-dependent decrease of oocyte volume was observed. Imbalances in the oogenesis process, induction of vitellogenin in males and the absence of pregnancies highlight that environmental relevant concentrations of EE2 have the potential to negatively affect pipefish populations, most of them inhabiting coastal areas where oestrogenic contamination is more prevalent.