Biology subjects

Madouasse, A.

Publications and source records attributed to Madouasse, A..

2 recordsLinked to original sources

bioRxiv2026

Potential for real-time health and welfare monitoring in experimental rabies infection in red fox (Vulpes vulpes) using implants

Monitoring and improving animal health and welfare is a pressing need. Technological advances are increasing our ability to do so in a range of settings but currently, there are limited uses in experimental settings for less common model animals. Red foxes (Vulpes vulpes) are maintained by the French National Agency for Food, Environmental, and Occupational Health and Safety (ANSES) for regulatory and research purposes, primarily related to its role as a European Union and French Reference Laboratory for rabies and Echinococcus spp. In 2022, four foxes were surgically fitted with internal implants that recorded body temperature and activity levels and subsequently inoculated with rabies virus (RABV). Retrospectively, we tested the potential of these two variables to provide an early warning for the onset of rabies symptoms. We applied two anomaly detection algorithms (Shewhart and EWMA) with varying confidence levels to the data sets and compared how early the different models could detect significant changes while limiting false alarms during the calibration period. We hypothesized that body temperatures would rise significantly and foxes would significantly alter their activity levels at the beginning of infection, both at an earlier stage than is detectable through direct observation. We found that foxes significantly changed their activity during infection. We were best able to detect these changes using the EWMA algorithm, in some cases producing consecutive alarms up to two weeks before the death of an animal, while limiting false alarms. We found no evidence of fever in any of the infected foxes and body temperature did not appear to be a reliable indicator of foxes health. While here we applied our methods to a particularly severe and rarely implemented model with a very small sample size, this proof of concept illustrates the potential of these methods for a wide range of other situations that would benefit from similar long-term monitoring, including experimental protocols with milder clinical signs and routine monitoring for unexpected declines in health or welfare.

animal behavior and cognition↗

bioRxiv2022

Seasonality of host-seeking Ixodes ricinus nymph abundance in relation to climate

There is growing concern about climate change and its impact on human health. Specifically, global warming could increase the probability of emerging infectious diseases, notably because of changes in the geographical and seasonal distributions of disease vectors such as mosquitoes and ticks. For example, the range of Ixodes ricinus, the most common and widespread tick species in Europe, is currently expanding northward and at higher altitudes. However, little is known about the seasonal variation in tick abundance in different climates. Seasonality of I. ricinus is often based on expert opinions while field surveys are usually limited in time. Our objective was to describe seasonal variations in I. ricinus abundance under different climates. To this end, a seven-year longitudinal study, with monthly collections of I. ricinus host-seeking nymphs, was carried out in France, in six locations corresponding to different climates. Tick data were log-transformed and grouped between years so as to obtain seasonal variations for a typical year. Daily average temperature was measured during the study period. Seasonal patterns of nymph abundance were established for the six different locations using linear harmonic regression. Model parameters were estimated separately for each location. Seasonal patterns appeared different depending on the climate considered. Western temperate sites showed an early spring peak, a summer minimum and a moderate autumn and winter abundance. More continental sites showed a later peak in spring, and a minimum in winter. The peak occurred in summer for the mountainous site, with an absence of ticks in winter. In all cases except the mountainous site, the timing of the spring peak could be related to the sum of degree days since the beginning of the year. Winter abundance was positively correlated to the corresponding temperature. Our results highlight clear patterns in the different sites corresponding to different climates, which allow further forecast of tick seasonality under changing climate conditions.

ecology↗