Individual and Combined Effects of Paternal Deprivation and Developmental Exposure to Firemaster 550 on Socio-Emotional Behavior in Prairie Voles

Abstract

The prevalence of neurodevelopmental disorders (NDDs) is rapidly rising, suggesting a confluence of environmental factors that are likely contributing, including developmental exposure to environmental contaminants. Unfortunately, chemical exposures and social stressors frequently occur simultaneously in many communities, yet very few studies have sought to establish the combined effects on neurodevelopment or behavior. Social deficits are common to many NDDs, and we and others have shown that exposure to the chemical flame retardant mixture, Firemaster 550 (FM 550), or paternal deprivation impairs social behavior and neural function. Here, we used a spontaneously prosocial animal model, the prairie vole (Microtus ochrogaster), to explore the effects of perinatal chemical (FM 550) exposure alone or in combination with an early life stressor (paternal absence) on prosocial behavior. Dams were exposed to vehicle (sesame oil) or 1000 µg FM 550 orally via food treats from conception through weaning and the paternal absence groups were generated by removing the sires the day after birth. Adult offspring of both sexes were then subjected to open-field, sociability, and a partner preference test. Paternal deprivation (PD)-related effects included increased anxiety, decreased sociability, and impaired pair-bonding in both sexes. FM 550 effects include heightened anxiety and partner preference in females but reduced partner preference in males. The combination of FM 550 exposure and PD did not exacerbate any behaviors in either sex except for distance traveled by females in the partner preference test and, to a lesser extent, time spent with, and the number of visits to the non-social stimulus by males in the sociability test. FM 550 ameliorated the impacts of parental deprivation on partner preference behaviors in both sexes. This study is significant because it provides evidence that chemical and social stressors can have unique behavioral effects that differ by sex but may not produce worse outcomes in combination.

Skeletal effects following developmental flame-retardant exposure are specific to sex and chemical class in the adult Wistar rat

“…Those data showed no indication of any gross mechanical impairment, and no animals showed any signs of impaired movement or mobility during behavioral tasks conducted on or around PND 90 (Witchey et al, 2020). Additionally, no evidence of impaired gross motor function was observed in any of our other prior behavioral studies on FM 550 (Patisaul et al, 2013b;Baldwin et al, 2017a;Gillera et al, 2022). Regardless, disrupted femoral skeletal organization was apparent in PND 250 FM 550 males in our prior study and less so in the older males tested herein.…”

Identification of hippocampal area CA2 in hamster and vole brain

“…Although mice are commonly used in neuroscience research because of their ease of genetic manipulation, prairie voles ( Microtus ochrogaster ) and Syrian hamsters ( Mesocricetus auratus ) are also used in behavioral studies of social learning and memory, pair bonding, and aggression due to their specific behavioral characteristics. For example, prairie voles exhibit monogamous pair bonding and alloparenting behavior, so they are valuable model organisms of prosocial behaviors (Gillera et al, 2022; Stetzik et al, 2018). In contrast, both male and female Syrian hamsters are naturally antagonistic, which makes them ideal for study of social dominance and aggression (Cooper et al, 2009; Solomon et al, 2009; Taylor et al, 2022).…”

Fathers’ presence and adolescents’ interpersonal relationship quality: Moderated mediation model

“…There have also been studies that emphasize the importance of fathers to children’s growth from the perspective of the father’s absence. For example, the absence of fathers may lead to children’s unhappiness, anxiety, poor social skills, physical illness, cognitive impairment, and depression ( Billah et al, 2022 ; Culpin et al, 2022 ; Farooqui and Barolia, 2022 ; Gillera et al, 2022 ; Rodríguez Sánchez, 2022 ). In particular, to improve fathers’ initiative to participate in their children’s upbringing, several scholars worldwide have discussed the issue of providing or extending paternity leave ( Knoester et al, 2019 ; Petts et al, 2020 ; Wray, 2020 ).…”