Towards the quantitative characterization of piglet robustness to weaning: A modelling approach

M. Revilla et al., 69th Annual meeting of the european federation of animal science (EAAP), Dubrovnik, Croatie, 27-31 août 2018 

Weaning is a critical phase in swine production conditions because piglets cope with different stressors that impact its health. During this period, the prophylactic use of antibiotics is still frequent to limit piglet morbidity, which raises economic and public health concerns such as the growing number of antimicrobial-resistant agents. With the interest of developing tools for assisting health and management decisions around weaning, it is key to provide robustness indexes that inform on the animal resilience to weaning. This task is hampered by the multiple-component nature of robustness. This work aimed at developing a modelling approach for facilitating the quantification of piglet resilience to weaning. We monitored 414 Large White pigs housed and fed conventionally during the post-weaning period without antibiotic administration. Body weight and diarrhoea scores were recorded before and after weaning. We constructed a dynamic model based on the Gompertz-Makeham law to describe live weight during the first 75 days after weaning following the rationale that the animal response is partitioned in two time windows (a perturbation and a recovery window). The transition time between the two windows is individual specific as well as model calibration, performed for each animal. The model captured the weight dynamics of animals at different degrees of perturbation. The power of the model is that it provides biological parameters that inform on the amplitude and length of perturbation, and the rate of animal recovery. We are currently investigating how to combine these proxy parameters to provide a robustness/resilience index to weaning. Next step is to correlate this index with individual diarrhoea scores and other health status measurements such as blood biomarkers and faecal microbiota diversity.
We foresee that this study will provide a step forward in the quantitative characterisation of robustness.