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Moisan, M.-P.

Publications and source records attributed to Moisan, M.-P..

5 recordsLinked to original sources

Daily feeding rhythms may play a role in the genetic variability of feed efficiency in growing pigs

AO_SCPLOWBSTRACTC_SCPLOWImproving feed efficiency in pigs is essential for reducing production costs and environmental impacts. This study examines the influence of circadian feeding rhythms and genetic polymorphisms on feed efficiency variability using two pig lines divergently selected for Residual Feed Intake (RFI) over ten generations. Feeding behavior was monitored using automatic concentrate dispensers, recording 6,494,097 visits from 3,824 pigs to analyze meal frequency, duration, and diurnal patterns. LRFI pigs ate less frequently, with larger meals and longer durations, they exhibited two distinct feeding peaks: one around 8:00 AM and a higher one at 5:00 PM and they consumed more feed during the diurnal period and less at night. HRFI pigs showed a smoother, less rhythmic feeding behavior with increased nocturnal intake. The differences between the two RFI lines became more pronounced as the number of generations of selection increased, suggesting a genetic basis. Feeding behaviors, including intake during the two main diurnal peaks, were found to be heritable (heritability estimates: 0.30-0.40) and genetic correlations were observed between feed intake and RFI, especially for intake between the two peaks. Then, we investigated the evolution of allele frequencies of single nucleotide polymorphisms (SNPs) in DNA sequences surrounding 10 core clock genes (ARNTL, CLOCK, CRY1, CRY2, NPAS2, NR1D1, PER1, PER2, PER3, RORA) along generations of selection. SNPs with significant frequency changes were mapped to regulatory regions and transposable elements, especially in HRFI line, suggesting potential functional impacts on circadian regulation. These results underscore the role of feeding behavior and genetic variation in feed efficiency, offering insights for breeding programs aimed at improving metabolic efficiency and sustainability in pig production.

zoology↗

Effects of a temporary period on pasture on the transcriptomic signature of horses housed in individual boxes

AO_SCPLOWBSTRACTC_SCPLOWPasture access is widely recognized for its welfare, behavioural, and health benefits in horses compared to individual stabling. Our recent studies have shown that even short-term pasture exposure enhances welfare and induces lasting changes in gut microbiota, promoting health-associated bacterial populations. This study investigated the transcriptomic signature of 22 horses following a standardized pasture protocol, with peripheral blood gene expression analysed before pasture access (T0) and three months after returning to individual stabling (T1). First, using sPLS regression, we correlated gene expression profiles with behavioural welfare indicators measured at T0 and T1. Horses with pasture access exhibited significantly altered blood transcriptome compared to controls, with aggressiveness towards humans emerging as the strongest behavioural correlate of gene expression. Bioinformatic analyses revealed that aggressiveness-associated genes were linked to inflammation, apoptosis, and cell differentiation/growth. Then, horses with pasture access were divided in resilient and non-resilient according to the improvement of their behaviour after time on pasture. Differentially expressed genes post versus pre- pasture, compared between resilient and non-resilient horses for aggressiveness showed that inflammatory signals were downregulated in both subgroups, with a more pronounced effect in resilient horses. This suggests that resilient individuals are better equipped to modulate inflammatory responses in low-stress environments like pasture. Surprisingly, for unresponsiveness to the environment--a trait linked to depressive-like states--resilient horses displayed increased inflammatory signaling (e.g., IRF and CD40 activation) post-pasture, while non-resilient horses showed activation of anti-inflammatory PPAR signaling. Notably, non-resilient horses exhibited molecular signatures associated with organismal death, morbidity, and growth failure, indicating maladaptive physiological states. In contrast, resilient horses demonstrated activation of growth-related pathways (e.g., BMP2 and BMPR1A), suggesting a shift toward anabolic and developmental processes. This study underscores the behavioural and molecular benefits of pasture access for horses, particularly in reducing aggressiveness and inflammatory signaling in resilient individuals. The findings highlight the complex interplay between behaviour, inflammation, and resilience, with pasture access promoting adaptive physiological and molecular responses. Further research is needed to elucidate the long-term implications of these transcriptomic changes and their broader relevance to equine welfare.

animal behavior and cognition↗

Time-restricted feeding prevents memory impairments induced by obesogenic diet consumption in mice, in part through hippocampal thyroid hormone signaling.

The consumption of calorie-rich diet has adverse effects on short and long-term memory, especially when introduced early in life when the brain is still maturing. Time-restricted feeding (TRF) without calorie restriction has proven to be an efficient strategy to reduce the deleterious effects of diet-induced obesity on metabolism. TRF was also shown to be beneficial to restore long-term memory in Alzheimer rodent models. Here, we provide evidence that four weeks of TRF restore the rhythmicity of some metabolic parameters together with short and long-term memory in mice fed a high fat-high sucrose (HFS) diet since weaning. Hippocampal translatome analyses indicated that impaired memory of mice under ad libitum HFS diet is accompanied by changes in genes associated with thyroid hormone signaling and astrocytic genes involved in the regulation of glutamate neurotransmission. TRF restored the diurnal expression variation of part of these genes and intra-hippocampal infusion of T3, the active form of thyroid hormone, rescued the memory performances of ad libitum HFS diet-fed mice. Thus, TRF demonstrates positive effects on both metabolism and memory in mice fed an obesogenic diet, highlighting this nutritional approach as a powerful tool in addressing obesity and its related comorbidities in mice. The analogous time-restricted eating in humans is an easy to implement lifestyle intervention that should now be tested in obese adolescents with memory alterations.

neuroscience↗

Strain-specific changes in nucleus accumbens transcriptome and motivation for food reward in mice exposed to maternal separation

Adversity in childhood exerts enduring effects on brain and increases the vulnerability to psychiatric diseases. It also leads to a higher risk for eating disorders and obesity. We hypothesised that neonatal stress in mice affects motivation to obtain palatable food in adulthood and changes gene expression in reward system. Male and female pups from C57Bl/6J and C3H/HeN mice strains were subjected to a daily maternal separation (MS) protocol from PND2 to PND14. In adulthood, their motivation for palatable food reward was assessed in operant cages. Compared to control mice, male and female C3H/Hen mice exposed to MS significantly did more lever presses to obtain palatable food especially when the effort required to obtain the reward is high. Transcriptional analysis reveals 375 genes differentially expressed in the nucleus accumbens of male MS C3H/HeN mice compared to the control group, some of these being associated with the regulation of the reward system (e.g. Gnas, Pnoc). Interestingly, C57Bl/6J mice exposed to MS did not show any alteration in their motivation to obtain a palatable reward nor significant changes in gene expression in the nucleus accumbens. In conclusion, neonatal stress produces lasting changes in motivation for palatable food in C3H/HeN offspring but has no impact in C57Bl/6J offspring. These behavioural alterations are accompanied by drastic changes in gene expression specifically within the nucleus accumbens, a key structure in the regulation of motivational processes.

neuroscience↗

Microbiota and stress: a loop that impacts memory

Chronic stress and the gut microbiota appear to comprise a feed-forward loop, which contributes to the development of depressive disorders. Evidence suggests that memory can also be impaired by either chronic stress or microbiota imbalance. However, it remains to be established whether these could be a part of an integrated loop model and be responsible for memory impairments. To shed light on this, we used a two-pronged approach in Japanese quail: first stress-induced alterations in gut microbiota were characterized, then we tested whether this altered microbiota could affect brain and memory function when transferred to a germ-free host. The cecal microbiota of chronically stressed quails was found to be significantly different from that of unstressed individuals with lower and {beta} diversities and increased Bacteroidetes abundance largely represented by the Alistipes genus, a well-known stress target in rodents and humans. The transfer of this altered microbiota into germ-free quails decreased their spatial and cue-based memory abilities as previously demonstrated in the stressed donors. The recipients also displayed increased anxiety-like behavior, reduced basal plasma corticosterone levels and differential gene expression in the brain. Furthermore, cecal microbiota transfer from a chronically stressed individual was sufficient to mimic the adverse impact of chronic stress on memory in recipient hosts and this action may be related to the Alistipes genus. Our results provide evidence of a feed-forward loop system linking the microbiota-gut-brain axis to stress and memory function and suggest that maintaining a healthy microbiota could help alleviate memory impairments linked to chronic stress.

animal behavior and cognition↗