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Last update: May 2021

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Modelling of nutrient utilization and precision feeding of lactating sows

PhD : precision feeding of lactating sows
New feeding systems to better adapt the nutritional intake to the requirements of each lactating sow.

Variability of nutritional requirements and feed intake

Nutritional requirements of lactating sows mainly depend on milk yield (figure 1) and greatly vary across individuals. However, the same diet is generally delivered to the whole herd. Feed intake is also insufficient to meet nutritional requirements (figure 2), especially those of primiparous sows. Sows facing negative nutritional balances maintain milk production with body reserves. This mobilization results in negative consequences on litter growth and subsequent reproductive performances. The aim of this thesis is to improve the adjustment of nutritional intake and requirements of each sow.

sow - milk production

Figure 1: A huge effect of individual milk production on daily nutritional requirements (Gauthier, 2017)

sow - individual feed intake

Figure 2: A huge effect of individual feed intake on nutritional balances (Gauthier, 2017)

Towards a precision approach

At the same time, acquiring data on sows and their environment at a high-throughput allows development of new precision feeding systems, in the hope of improving technical performances, reducing feeding costs, and limiting environmental impacts. Such feeding systems have already been tested with growing pigs (Pomar et al., 2009) and gestating sows (Dourmad et al., 2017). They allow the improvement of technical performances, the reduction of feeding costs and a better control of nutritional excesses and nutrient waste. The research question deals with new precision feeding techniques applied to lactating sows and the definition in real time of both milk production and nutritional requirements.

Building of an individual-based model of the lactating sow

The first step is to build a nutritional and individual-based model of the lactating sow. Such a model does not exist at the current time. It will be based on herd nutritional model like InraPorc® (Dourmad et al., 2008). It will be then included in a new decision support system, in order to calculate the right composition of the diet to be given for each day. Different feeds will be used with different nutritional values to better meet the nutritional requirements of each lactating sow.

Raphaël Gauthier is working on this subject of thesis since the 1st november of 2017 for 3 years. He is supervised by Jean-Yves Dourmad and Christine Largouet (Agrocampus Ouest) in the team Swine Systems.
This work, referred as ANR-16-CONV-0004, was supported by the French National Research Agency under the “Investments for the Future Program”.

Logo institut de convergence #DigitAg

Thesis co-funded by #DigitAg.


Raphaël Gauthier : raphael.gauthier[at]
Jean-Yves Dourmad : jean-yves.dourmad[at]
Christine Largouet (Agrocampus Ouest, Irisa-Inria)


  • Dourmad, J.Y., Étienne, M., Valancogne, A., Dubois, S., van Milgen, J., and J. Noblet. 2008. InraPorc: A model and decision support tool for the nutrition of sows. Anim. Feed Sci. Technol. 143:372–386. [DOI]
  • Dourmad, J.Y., Brossard, L., Pomar, C., Pomar, J., Gagnon, P., and L. Cloutier. 2017. Development of a decision support tool for precision feeding of pregnant sows, in: 8. European Conference on Precision Livestock Farming (ECPLF), Nantes. 584-592. [Lien]
  • Gauthier R. 2017. Modélisation des besoins nutritionnels et alimentation de précision des truies en lactation. Mémoire de fin d'études. Master productions animales. Angers. École Supérieure d'Agricultures (ESA), 72 p.
  • Pomar, C., Hauschild, L., Zhang, G.-H., Pomar, J., and P.A. Lovatto. 2009. Applying precision feeding techniques in growing-finishing pig operations. Revista Brasileira de Zootecnia 38:226–237. [DOI]