Jane L. Hurst

Bush dogs (Speothos venaticus) are cooperatively breeding South American canids with relatively unstudied behavior. Here, we study a group of zoo‐housed bush dogs to investigate the impact of pack structure changes on their collective movements, social hierarchy and social network structure. Data were collected on dominance interactions and group movements within the pack over 10 months, split into three phases: (1) during the pregnancy of the breeding female, (2) post‐pup birth, and (3) post‐removal of an adult female. Our results indicate that in this pack, bush dogs formed a single social hierarchy with the breeding male as the highest‐ranking member, contrasting with a previous study finding separate male and female hierarchies. However, this difference may be due to the physical limitations of the breeding female in our study, caused by pregnancy and old age. Submission behaviors contributed more to social rank than dominance behaviors. Following the pup birth, the linearity and steepness of the social hierarchy and the frequency of submission behaviors in the group increased, while the female that was least related to the breeding female became the lowest ranking group member. The subsequent removal of this low‐ranking female had minimal impact on social structure. Higher‐ranking individuals initiated more single‐file lines, likely facilitating cooperative hunting and group travel. This study contributes valuable insights into the social structure and dynamics of a zoo‐housed bush dog group and provides a basis for the use of David's score and social network analysis to monitor bush dog social groups to inform ex‐situ management.

To manage ex situ breeding populations effectively, it is important to understand the factors that may lead to reproductive failure. In this study, we aim to understand factors associated with reproductive success in zoo‐housed bush dogs (Speothos venaticus) , and form evidence‐based recommendations for their breeding management. We distributed a survey to global institutions housing bush dogs to collect data on factors which may affect litter survival. Responses were obtained from 30 zoos across 13 countries, providing data on 125 litter births between 2012 and 2022. Information from the Zoological Information Management System (ZIMS) and studbook records supplemented this dataset. We found that within northern temperate regions, the number of pups reared to the age of 1 month in bush dog litters ( n = 112 litters) is linked to the ages of breeding individuals, prior breeding experience of females and birth season. The number of pups reared per litter declines with advancing maternal age, but this decline can be reduced by pairing with an older male; experienced females rear more pups per litter than inexperienced females, and litters born in the summer have better survival outcomes than other seasons. Sharing data between zoos provides greater statistical power to identify challenges associated with breeding lesser‐researched species, allowing zoos to overcome these challenges through evidence‐based management changes.

Relationships between adult females are fundamental to understanding diversity in animal social systems. While cooperative relationships between kin are known to promote fitness benefits, the proximate mechanisms underlying this are not well understood. Here we show that when related female house mice (Mus musculus domesticus) cooperate to rear young communally, those with higher endogenous oxytocin levels have more egalitarian and successful cooperative relationships. Sisters with higher oxytocin concentrations in the paraventricular nucleus (PVN) of the hypothalamus weaned significantly more offspring, had lower reproductive skew and spent more equal proportions of time in the nest. By contrast, PVN oxytocin was unrelated to the number of weaned offspring produced in the absence of cooperation, and did not vary in response to manipulation of nest site availability or social cues of outgroup competition. By linking fitness consequences of cooperation with oxytocin, our findings have broad implications for understanding the evolution of egalitarian social relationships.

Breeding females can cooperate by rearing their offspring communally, sharing synergistic benefits of offspring care but risking exploitation by partners. In lactating mammals, communal rearing occurs mostly among close relatives. Inclusive fitness theory predicts enhanced cooperation between related partners and greater willingness to compensate for any partner under-investment, while females are less likely to bias investment towards own offspring. We use a dual isotopic tracer approach to track individual milk allocation when familiar pairs of sisters or unrelated house mice reared offspring communally. Closely related pairs show lower energy demand and pups experience better access to non-maternal milk. Lactational investment is more skewed between sister partners but females pay greater energetic costs per own offspring reared with an unrelated partner. The choice of close kin as cooperative partners is strongly favoured by these direct as well as indirect benefits, providing a driver to maintain female kin groups for communal breeding.

Chemical communication by females remains poorly understood, with most attention focused on female advertisement of sexual receptivity to males or mother–offspring communication. However, in social species, scents are likely to be important for mediating competition and cooperation between females determining individual reproductive success. Here, we explore chemical signaling by female laboratory rats ( Rattus norvegicus ) to test i) whether females target their deployment of scent information differentially according to their sexual receptivity and the genetic identity of both female and male conspecifics signaling in the local environment and ii) whether females are attracted to gain the same or different information from female scents compared to males. Consistent with targeting of scent information to colony members of similar genetic background, female rats increased scent marking in response to scents from females of the same strain. Females also suppressed scent marking in response to male scent from a genetically foreign strain while sexually receptive. Proteomic analysis of female scent deposits revealed a complex protein profile, contributed from several sources but dominated by clitoral gland secretion. In particular, female scent marks contained a series of clitoral-derived hydrolases and proteolytically truncated major urinary proteins (MUPs). Manipulated blends of clitoral secretion and urine from estrus females were strongly attractive to both sexes, while voided urine alone stimulated no interest. Our study reveals that information about female receptive status is shared between females as well as with males, while clitoral secretions containing a complex set of truncated MUPs and other proteins play a key role in female communication.

Background: A rapid, accurate method to identify and to age-grade mosquito populations would be a major advance in predicting the risk of pathogen transmission and evaluating the public health impact of vector control interventions. Whilst other spectrometric or transcriptomic methods show promise, current approaches rely on challenging morphological techniques or simple binary classifications that cannot identify the subset of the population old enough to be infectious. In this study, the ability of rapid evaporative ionisation mass spectrometry (REIMS) to identify the species and age of mosquitoes reared in the laboratory and derived from the wild was investigated. Results: The accuracy of REIMS in identifying morphologically identical species of the Anopheles gambiae complex exceeded 97% using principal component/linear discriminant analysis (PC-LDA) and 84% based on random forest analysis. Age separation into 3 different age categories (1 day, 5–6 days, 14–15 days) was achieved with 99% (PC-LDA) and 91% (random forest) accuracy. When tested on wild mosquitoes from the UK, REIMS data could determine the species and age of the specimens with accuracies of 91 and 90% respectively. Conclusions: The accuracy of REIMS to resolve the species and age of Anopheles mosquitoes is comparable to that achieved by infrared spectroscopy approaches. The processing time and ease of use represent significant advantages over current, dissection-based methods. Importantly, the accuracy was maintained when using wild mosquitoes reared under differing environmental conditions, and when mosquitoes were stored frozen or desiccated. This high throughput approach thus has potential to conduct rapid, real-time monitoring of vector populations, providing entomological evidence of the impact of alternative interventions.

Cruciate ligaments (CL) of the knee joint are injured following trauma or aging. MicroRNAs (miRs) are potential therapeutic targets in musculoskeletal disorders, but there is little known about the role of miRs and their expression ligaments during aging. This study aimed to (1) identify if mice with normal physical activity, wild‐stock house mice are an appropriate model to study age‐related changes in the knee joint and (2) investigate the expression of miRs in aging murine cruciate ligaments. Knee joints were collected from 6 and 24 months old C57BL/6 and wild‐stock house mice (Mus musculus domesticus) for ligament and cartilage (OARSI) histological analysis. Expression of miR targets in CLs was determined in 6‐, 12‐, 24‐, and 30‐month‐old wild‐stock house mice, followed by the analysis of predicted mRNA target genes and Ingenuity Pathway Analysis. Higher CL and knee OARSI histological scores were found in 24‐month‐old wild‐stock house mice compared with 6‐ and 24‐month‐old C57BL/6 and 6‐month‐old wild‐stock house mice (p < 0.05). miR‐29a and miR‐34a were upregulated in 30‐month‐old wild‐stock house mice in comparison with 6‐, 12‐, and 24‐month‐old wild‐stock house mice (p < 0.05). Ingenuity Pathway Analysis on miR‐29a and 34a targets was associated with inflammation through interleukins, TGFβ and Notch genes, and p53 signaling. Collagen type I alpha 1 chain (COL1A1) correlated negatively with both miR‐29a (r = −0.35) and miR‐34a (r = −0.33). The findings of this study support wild‐stock house mice as an appropriate aging model for the murine knee joint. This study also indicated that miR‐29a and miR‐34a may be potential regulators of COL1A1 gene expression in murine CLs.

Background: A rapid, accurate method to identify and to age grade mosquito populations would be a major advance in predicting the risk of pathogen transmission and evaluating the public health impact of vector control interventions. Whilst other chemometric methods show promise, current approaches rely on challenging morphological techniques or simple binary classifications that cannot identify the subset of the population old enough to be infectious. In this study, the ability of Rapid Evaporative Ionisation Mass Spectrometry (REIMS) to identify the species, sex and age of mosquitoes reared in the laboratory and derived from the wild was investigated. Results: The accuracy of REIMS in identifying morphologically identical species of the Anopheles gambiae complex exceeded 97 % using principal component/linear discriminant analysis (PC-LDA) and 84 % based on random forest analysis. Age separation into 3 different age categories (1 d, 5-6 d, 14-15 d.) was achieved with 99 % (PC-LDA) and 94 % (random forest) accuracy, after including three species and storing samples at room temperature for up to 11 days. When tested on wild mosquitoes from the UK, REIMS data could determine the species and age of the specimens with accuracies of 91 and 90 % respectively. Conclusions: The accuracy of REIMS to resolve the species and age of Anopheles mosquitoes is comparable to that achieved by chemometric approaches. The processing time and ease of use represent significant advantages over current, dissection-based methods. Importantly the accuracy was maintained when using wild mosquitoes reared under differing environmental conditions, and when mosquitoes were stored frozen or desiccated. This high throughput approach thus has potential to conduct rapid, real- time monitoring of vector populations, providing entomological evidence of the impact of alternative interventions.

Changes in the abundance of individual proteins in the proteome can be elicited by modulation of protein synthesis (the rate of input of newly synthesized proteins into the protein pool) or degradation (the rate of removal of protein molecules from the pool). A full understanding of proteome changes therefore requires a definition of the roles of these two processes in proteostasis, collectively known as protein turnover. Because protein turnover occurs even in the absence of overt changes in pool abundance, turnover measurements necessitate monitoring the flux of stable isotope labeled precursors through the protein pool such as labeled amino acids or metabolic precursors such as ammonium chloride or heavy water. In cells in culture, the ability to manipulate precursor pools by rapid medium changes is simple, but for more complex systems such as intact animals, the approach becomes more convoluted. Individual methods bring specific complications, and the suitability of different methods has not been comprehensively explored. In this study we compare the turnover rates of proteins across four mouse tissues, obtained from the same inbred mouse strain maintained under identical husbandry conditions, measured using either [ ¹³ C ₆ ]lysine or [ ² H ₂ ]O as the labeling precursor. We show that for long-lived proteins, the two approaches yield essentially identical measures of the first order rate constant for degradation. For short-lived proteins, there is a need to compensate for the slower equilibration of lysine through the precursor pools. We evaluate different approaches to provide that compensation. We conclude that both labels are suitable, but careful determination of precursor enrichment kinetics in amino acid labeling is critical and has a considerable influence on the numerical values of the derived protein turnover rates.