Effect of Chronic Social Stress on Prenatal Transfer of Antitetanus Immunity in Captive Breeding Rhesus Macaques (Macaca mulatta)

Maternal Mental Disorders and Pediatric Infectious Diseases: A Retrospective Cohort Study

BACKGROUND

Maternal stress and depression are associated with infections in offspring, but there is a paucity of data for other mental disorders.

METHODS

We conducted a retrospective cohort study of 832,290 children born between 2006 and 2016 in hospitals of Quebec, Canada. We identified maternal mental disorders before and during pregnancy, and admissions for otitis media, pneumonia, infectious enteritis and other infections in children before 13 years of age. We used Cox proportional hazards regression to estimate hazard ratios (HRs) with 95% confidence intervals (CI) for the association between maternal mental disorders and the risk of pediatric infectious diseases, adjusted for maternal age, comorbidity, socioeconomic disadvantage, and other confounders.

RESULTS

The incidence of pediatric infection hospitalization was higher for maternal mental disorders compared with no disorder (66.1 vs. 41.1 cases per 1000 person-years). Maternal mental disorders were associated with 1.38 times the risk of otitis media (95% CI: 1.35-1.42), 1.89 times the risk of bronchitis (95% CI: 1.68-2.12), and 1.65 times the risk of infectious enteritis in offspring (95% CI: 1.57-1.74). Stress and anxiety disorders (HR 1.49, 95% CI: 1.46-1.53) and personality disorders (HR 1.55, 95% CI: 1.49-1.61) were more strongly associated with the risk of pediatric infection hospitalization than other maternal mental disorders. Associations were prominent in the first year of life and weakened with age.

CONCLUSIONS

Maternal mental disorders are risk factors for infectious disease hospitalization in offspring. Women with mental disorders may benefit from psychosocial support to reduce the risk of serious infections in their children.

Neonatal Immune System Ontogeny: The Role of Maternal Microbiota and Associated Factors. How Might the Non-Human Primate Model Enlighten the Path?

Interactions between the immune system and the microbiome play a crucial role on the human health. These interactions start in the prenatal period and are critical for the maturation of the immune system in newborns and infants. Several factors influence the composition of the infant's microbiota and subsequently the development of the immune system. They include maternal infection, antibiotic treatment, environmental exposure, mode of delivery, breastfeeding, and food introduction. In this review, we focus on the ontogeny of the immune system and its association to microbial colonization from conception to food diversification. In this context, we give an overview of the mother-fetus interactions during pregnancy, the impact of the time of birth and the mode of delivery, the neonate gastrointestinal colonization and the role of breastfeeding, weaning, and food diversification. We further review the impact of the vaccination on the infant's microbiota and the reciprocal case. Finally, we discuss several potential therapeutic interventions that might help to improve the newborn and infant's health and their responses to vaccination. Throughout the review, we underline the main scientific questions that are left to be answered and how the non-human primate model could help enlighten the path.

Appeasing Pheromones for the Management of Stress and Aggression during Conservation of Wild Canids: Could the Solution Be Right under Our Nose?

Simple Summary

Many canid species are declining globally. It is important to conserve these species that often serve as important predators within ecosystems. Continued human expansion and the resulting habitat fragmentation necessitate conservation interventions, such as translocation, artificial pack formation, and captive breeding programs. However, chronic stress often occurs during these actions, and can result in aggression, and the physiological suppression of immunity and reproduction. Limited options are currently available for stress and aggression management in wild canids. Pheromones provide a promising natural alternative for stress management; an appeasing pheromone has been identified for multiple domestic species and may reduce stress and aggression behaviours. Many pheromones are species-specific, and the appeasing pheromone has been found to have slight compositional changes across species. In this review, the benefits of a dog appeasing pheromone and the need to investigate species-specific derivatives to produce more pronounced and beneficial behavioural and physiological modulation in target species as a conservation tool are examined.

Abstract

Thirty-six species of canid exist globally, two are classified as critically endangered, three as endangered, and five as near threatened. Human expansion and the coinciding habitat fragmentation necessitate conservation interventions to mitigate concurrent population deterioration. The current conservation management of wild canids includes animal translocation and artificial pack formation. These actions often cause chronic stress, leading to increased aggression and the suppression of the immune and reproductive systems. Castration and pharmaceutical treatments are currently used to reduce stress and aggression in domestic and captive canids. The undesirable side effects make such treatments inadvisable during conservation management of wild canids. Pheromones are naturally occurring chemical messages that modulate behaviour between conspecifics; as such, they offer a natural alternative for behaviour modification. Animals are able to distinguish between pheromones of closely related species through small compositional differences but are more likely to have greater responses to pheromones from individuals of the same species. Appeasing pheromones have been found to reduce stress- and aggression-related behaviours in domestic species, including dogs. Preliminary evidence suggests that dog appeasing pheromones (DAP) may be effective in wild canids. However, the identification and testing of species-specific derivatives could produce more pronounced and beneficial behavioural and physiological changes in target species. In turn, this could provide a valuable tool to improve the conservation management of many endangered wild canids.

Utility of Automated Feeding Data to Detect Social Instability in a Captive Breeding Colony of Rhesus Macaques (Macaca mulatta): A Case Study of Intrafamily Aggression

Some captive breeding colonies of rhesus macaques live in large outdoor multimale, multifemale social groups. These groups are composed of several matrilineal families, governed by a clear female dominance hierarchy. Aggression within the same or between different matrilineal families due to social instability can result in trauma and mortality. Therefore, a primary management goal is to detect emerging social unrest before the onset of significant fighting and wounding. Accordingly, groups are monitored routinely for changes in dominance and alliance relations as well as for increases in trauma frequency and severity. Decreased food intake is a normal physiologic response to acute stress; therefore, inappetence in key animals or groups of monkeys might be used as an indicator of increased social stress and emerging instability. An incident of intrafamily aggression occurred recently in a breeding group at our facility and resulted in considerable fighting. Because this compound was equipped with an automated feeding system that tracks the caloric intake of individual animals, we retrospectively analyzed feeding data to determine whether significant reduction in caloric consumption occurred prior to the onset of aggression, compared with baseline values. Neither the entire group nor individual families showed any significant differences in total caloric intake between baseline and previous 24 h values; however, the affected family exhibited a 20% reduction in total caloric during the 24 h prior to the aggression. Most notably, the deposed subfamily showed a marked 58% reduction in caloric intake during the prior 24 h, whereas remaining subfamilies showed no significant changes in intake. High-ranking animals of the group, including the α female, β female, and α male, similarly exhibited marked decreases in caloric intake during that period. These findings indicate that automated feeders can assist management staff with monitoring social stability in breeding colonies of rhesus macaque.

Effects of Transportation and Relocation on Immunologic Measures in Cynomolgus Macaques (Macaca fascicularis)

NHP are a small, but critical, portion of the animals studied in research laboratories. Many NHP are imported or raised at one facility and subsequently moved to another facility for research purposes. To improve our understanding of the effects of transportation and relocation on the NHP immune system, to minimize potential confounds associated with relocation, and to maximize study validity, we examined the phenotype and function of PBMC in cynomolgus macaques (Macaca fascicularis) that were transported approximately 200 miles by road from one facility to another. We evaluated the phenotype of lymphocyte subsets through flow cytometry, mitogen-specific immune responses of PBMC in vitro, and plasma levels of circulating cytokines before transportation, at approximately 24 h after arrival (day 2), and after 30 d of acclimation. Analyses of blood samples revealed that the CD3+ and CD4+ T-cell counts increased significantly, whereas NK+, NKT, and CD14+ CD16+ nonclassical monocyte subsets were decreased significantly on day 2 after relocation compared with baseline. We also noted significantly increased immune cell function as indicated by mitogen-specific proliferative responses and by IFNγ levels on day 2 compared with baseline. After 30 d of acclimation, peripheral blood CD4+ T-cells and monocyte counts were higher than baseline, whereas B-cell numbers were lower. The mitogen-induced responses to LPS and IFNγ production after stimulation with pokeweed mitogen or phytohemagglutinin remained significantly different from baseline. In conclusion, the effects of transportation and relocation on immune parameters in cynomolgus monkeys are significant and do not fully return to baseline values even after 30 d of acclimation.