A nonlinear ODE model for in vitro homoacetogenesis by human-colon bacteria is proposed and analysed. This model takes into account the biological and physical features of the experiment under consideration and the measurement process. An identifiability analysis is carried out, and the parameters of the model are identified using four different statistical description of the errors on the measurements. The estimated values will be used as prior estimates in a more ambitious modelling project of the carbohydrate trophic chain in the human colon.

The objectives of this study were to investigate the possibility of characterising animal robustness by using indicators based on the dynamics of energy allocation of the animal and to determine their genetic parameters. A total of 2 140 pigs, from the Piétrain NN Français line, were raised at the AXIOM boar testing station. This farm was equipped with automatic feeding system, recording individual weight and feed intake at each visit. We used a dynamic linear regression model to characterize the evolution of the allocation factor (αt) between cumulative net energy available, estimated from feed intake, and cumulative weight gain during fattening period. The variance of αt, that could be interpreted as an indicator of the response of the animal to perturbations/stress, showed moderate heritability (0.27 ±0.08). Our perspective is to further decompose the allocation factor into components to better characterise the robustness phenotype.

No abstract