Biology subjects

Bock, S.

Publications and source records attributed to Bock, S..

5 recordsLinked to original sources

bioRxiv2026

Buffaloed in Brandenburg: Germany's first Brush with Foot-and-Mouth Disease after four Decades of Freedom

Foot-and-mouth disease (FMD) virus is one of the most feared and most consequential pathogens of livestock worldwide. It can be spread rapidly by the transboundary movement of animals, animal products and byproducts. In January 2025, Germany detected its first FMD outbreak since 1988 in extensively reared water buffalo on a small farm in the state of Brandenburg, directly outside Berlin, the federal capital. Immediate control measures including a standstill for movements of susceptible animals and pre-emptive culling were implemented by the veterinary authorities. Whole-genome sequencing identified the virus as serotype O, topotype ME-SA, lineage SA-2018 and revealed extensive recombination, but cross-neutralization assays suggested good heterologous protection by an O/PanAsia-2 vaccine strain. Epidemiological back-calculation placed the time of virus introduction in late December 2024. Although the entry route remains unresolved, human-associated introduction is most likely. Network analysis revealed minimal farm connectivity, and simulations predicted low potential for onward transmission, which is consistent with the outbreak being ultimately restricted to a single herd. This event underscores the constant and unpredictable risk of introduction of the virus. Early detection through increased awareness and comprehensive differential diagnostics as well as the international collaboration of veterinary services, laboratories and experts are essential in the face of the global presence of FMD.

microbiology↗

bioRxiv2025

Sex- and age-differences in cellular hallmarks of aging in a species with female-biased longevity and environmental sex determination

Cellular hallmarks of aging have been discovered and characterized in a number of model species for studying aging biology - such as humans, mice, fruit flies, and nematodes. Whether these canonical age-related changes to cellular physiology are present across diverse species that have variable rates of demographic aging remains less studied. Here, we tested whether several ubiquitous cellular hallmarks of aging - mitochondrial function, reactive oxygen species generation, and inducible DNA damage - change with age and in a sex-dependent manner in a species with indeterminate growth and reproduction (painted turtles, Chrysemys picta). A further feature of their biology that recommends them for an ecological model of vertebrate aging is their female-biased longevity, despite an absence of genotypic sex determination. Thus lifespan and aging may be reliable features of sex-specific life-histories. We measured aspects of mitochondrial health (cellular basal, maximal, and spare oxygen consumption rates), cellular levels of reactive oxygen species, and aspects of DNA damage and repair from exposure to UVB. We used these measures across several physiological axes as proxies for age-related physiological dysfunction. We further assessed our measures across several populations of painted turtles. We found that sex explained the largest proportion of variation, with males differing from females in mitochondrial function, reactive oxygen species production, and inducible DNA damage. In several cases, age significantly interacted with sex, but the effect size was small relative to sex alone. Thus, we found that sex, rather than age or size, was a consistent predictor of cellular aging physiological in this species with where females live longer and age slower.

physiology↗

bioRxiv2025

Widespread sex-biased gene expression reflects female-biased longevity in a species with environmental sex determination

Sexes frequently differ in life history traits including body size, lifespan, and age at sexual maturity. Aging, the progressive decline in physiological function and cellular resilience over time, is a central process contributing to sex-specific life histories, yet the mechanisms driving sex differences in aging remain largely unresolved. Long-term mark-recapture efforts revealed a striking pattern of female-biased longevity in the painted turtle (Chrysemys picta), a species with temperature-dependent sex determination. As a result, this species provides a compelling system to examine the mechanisms of sex-specific aging in the absence of sex chromosomes. Here, we characterize sex- and age-associated patterns in the blood transcriptomes of wild painted turtles (n = 93). We identified widespread gene expression differences between females and males (2,347 genes; 13.4% of all filtered genes). In contrast, only six genes showed significant linear relationships with continuous age in both sexes. We also employed a machine learning approach which identified distinct sets of genes for which expression was predictive of age in each sex. Age-related gene expression patterns highlight both conserved molecular pathways with known roles in aging as well as novel gene targets. These findings suggest sex-specific molecular processes underlie sex-biased demographic aging and raise questions regarding the environmental and developmental drivers of sex-biased gene expression.

ecology↗

bioRxiv2023

Differential early-life survival underlies the adaptive significance of temperature-dependent sex determination in a long-lived reptile

O_LIMany ectotherms rely on temperature cues experienced during development to determine offspring sex. The first descriptions of temperature-dependent sex determination (TSD) were made over 50 years ago, yet an understanding of its adaptive significance remains elusive, especially in long-lived taxa. C_LIO_LIOne novel hypothesis predicts that TSD should be evolutionarily favored when two criteria are met - (a) incubation temperature influences annual juvenile survival and (b) sexes mature at different ages. Under these conditions, a sex-dependent effect of incubation temperature on offspring fitness arises through differences in age at sexual maturity, with the sex that matures later benefiting disproportionately from temperatures that promote juvenile survival. C_LIO_LIThe American alligator (Alligator mississippiensis) serves as an insightful model in which to test this hypothesis, as males begin reproducing nearly a decade after females. Here, through a combination of artificial incubation experiments and mark-recapture approaches, we test the specific predictions of the survival-to-maturity hypothesis for the adaptive value of TSD by disentangling the effects of incubation temperature and sex on annual survival of alligator hatchlings across two geographically distinct sites. C_LIO_LIHatchlings incubated at male-promoting temperatures consistently exhibited higher survival compared to those incubated at female-promoting temperatures. This pattern appears independent of hatchling sex, as females produced from hormone manipulation at male-promoting temperatures exhibit similar survival to their male counterparts. C_LIO_LIAdditional experiments show that incubation temperature may affect early-life survival primarily by affecting the efficiency with which maternally transferred energy resources are used during development. C_LIO_LIResults from this study provide the first explicit empirical support for the adaptive value of TSD in a crocodilian and point to developmental energetics as a potential unifying mechanism underlying persistent survival consequences of incubation temperature. C_LI

ecology↗

bioRxiv2023

Reconstruction of the molecular evolution of Usutu virus in Germany: Insights into virus emersion and circulation

Usutu virus (USUV) is a mosquito-borne flavivirus that is widely distributed in southern and central Europe. The zoonotic virus circulates primarily between birds and mosquitoes, can, however, in rare cases infect other mammals including humans. In the past USUV has been associated with mass mortalities in birds, formerly blackbirds and owls. Birds commonly succumb either due to the peracute nature of the infection or due to severe encephalitis. In Germany, USUV has spread rapidly since its first detection in 2010 in mosquitoes under the presence of susceptible host and vector species. Nonetheless, there is to date limited access to whole genome sequences resulting in the absence of in-depth phylogenetic and phylodynamic analyses. In this study, 118 wild and captive birds were screened using a nanopore sequencing platform with prior target enrichment via amplicons. Due to the high abundancy of Europe 3 and Africa 3 in Germany an ample quantity of associated whole genome sequences was generated and the most recent common ancestor could be determined for each lineage. The corresponding clock phylogeny revealed an introduction of USUV Europe 3 and Africa 3 into Germany three years prior to their first isolation in the avifauna in 2011 and 2014, respectively. Based on the clustering and temporal history of the lineages, evidence exists for the genetic evolution of USUV within Germany as well as new introductions thereof into the country.

evolutionary biology↗