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Biology subjects

Ferreira, S. C. M.

Publications and source records attributed to Ferreira, S. C. M..

3 recordsLinked to original sources

Compromised futures: gastrointestinal parasites reduce survival and recruitment but not reproductive performance in wild female spotted hyenas (Crocuta crocuta)

BackgroundGastrointestinal parasitic (GIP) infections can decrease the survival and reproductive performance of humans and livestock. Even so, the immediate and delayed fitness consequences of GIP in unmanaged wild mammal populations, particularly during the sensitive and energetically demanding early life stage, remain largely unknown. MethodsWe investigate non-invasively the effects of GIP during early life on the survival to adulthood, age at first reproduction and longevity of 68 individually known female spotted hyenas in the Serengeti National Park, Tanzania. We also test whether a high investment in gastrointestinal local immunity (i.e. faecal mucin and immunoglobulin A) and an elevated allostatic load (i.e. faecal glucocorticoid metabolites) decrease these measures of performance, when controlling for resource availability and maternal effects (i.e. maternal social rank) using logistic regression and Cox proportional hazards models. ResultsAncylostoma sp. infections and the level of immunoglobulin A both negatively associate with survival to adulthood, probably because of the damage caused by the parasite and resource allocation trade-off between immunity and maintenance. Conversely, maternal social rank has a positive influence on survival to adulthood and longevity. Immune responses, allostatic load and GIP do not affect the age at first reproduction, suggesting either no effect, a complex interaction between different life stages, or a more immediate time-dependent effect. ConclusionOur study highlights the critical role of GIP infections and maternal effects on early-life fitness and long-term outcomes in females of a wild carnivore, thereby contributing to our understanding of ecological dynamics in unmanaged ecosystems.

ecology↗

Anthropogenic land use exerts selection pressures on the resistome of a wild rodent

Antimicrobial resistance poses a significant global health challenge. However, the factors maintaining antimicrobial resistance genes (ARGs) in wildlife microbiomes remain unclear particularly in species inhabiting human-dominated landscapes. We analysed 875 gut metagenomes from wild house mice (Mus musculus) on German farms between 2016 and 2022 to identify environmental and host determinants of ARG occurrence. Using joint species distribution models, we quantified the influence of landscape, climate and mouse associated characteristics on the occurrence of individual ARGs and on trait dependence among genes. Environmental variables and livestock farming intensity explained more than 21% of ARG variation, whereas host characteristics accounted for less than 10%. Analysis of ARG traits revealed that agricultural land use and exposure to livestock increased the occurrence of mobile ARGs. Pig density was strongly associated with integron-encoded sulfonamide resistance genes and genes conferring tetracycline and beta-lactam resistance. Consistent with these findings, mouse resistomes closely resembled those of livestock manure. Taken together, our results show that landscape conditions, particularly farming intensity, shape the distribution of specific ARGs and mobile ARGs in house mice microbiomes. Understanding the factors impacting ARGs prevalence in wildlife is crucial for determining transmission of antimicrobial resistant microorganisms from animal and environmental reservoirs.

microbiology↗

Subspecies divergence, hybridisation and the spatial environment shape phylosymbiosis in the microbiome of house mice

Closely related host species share similar symbionts, yet how host genetics and the environment affect symbiont communities at different stages of host genetic divergence remains largely unknown. Similarly, it is unclear whether host-symbiont associations result from or contribute to host divergence. We examined the intestinal community of 619 wild-caught mice from Germanys European house mouse hybrid zone. Here, hybridisation upon secondary contact reflects divergence and could be traced gradually. Temporal and spatial factors were strong predictors of microbiome composition. Subspecies divergence predicted the composition similarity of the overall microbiome, specifically in the bacteria, parasite and fungal components. The effect of hybridisation was generally weak but significant for the fungal component. We confirmed our results in experiments with wild-derived inbred mice: subspecies genetic distances and hybridisation predicted the overall microbiome composition, and hybridisation further predicted fungal similarities among individuals. Fungi seemed more stable to the community perturbation of infection than other components of the microbiome. Differences between subspecies were more substantial across different microbiome components than those associated with hybridisation. Diverged microbiomes are a product of host divergence and are maintained by host genetics upon large environmental effects. These results provide a unique perspective into the ecoevolutionary processes shaping phylosymbiosis.

evolutionary biology↗