Main supervisors

Cécile GINANE (UMR1213 Herbivores INRAE, VetAgro Sup)

Email address: cecile.ginane@inrae.fr

Angélique FAVREAU-PEIGNÉ (UMR1198 BREED INRAE, Univ. Paris-Saclay)

Email address: angelique.favreau@inrae.fr

Co-supervisor

Pablo GREGORINI (Lincoln University, New-Zealand)

Email address: Pablo.Gregorini@lincoln.ac.nz

Scientific question/ Background/ Objectives and methodology/ Literature cited

Ruminant livestock systems are facing increasing climatic challenges that directly affect the availability of feed resources for farm animals. The use of varied feed resources, including local and/or by-product resources, plays a crucial role to compensate for the lack of forage resources and thus, to enhance the resilience of these systems. At the animal level, this involves adapting to a diversity and variety of feeds, varying in quality and availability, both behaviourally and physiologically. Feed diversity may also participate in improving animal welfare, which is a current concern of society and is essential for the overall quality of livestock production systems. Environmental enrichment is an increasingly investigated way of improving welfare[1]. Feeding enrichment, i.e. the diversification of the food on offer and its delivery methods, is a type of enrichment that has received little attention in livestock, particularly ruminants, despite its potential relevance. Domestic ruminants are generalists and choose diversified diets whenever they have the opportunity [2]. Eating a diversified diet appears to be a 'natural' behaviour for them. Thus, it raises the question of the value of feed diversity in satisfying their nutritional and behavioural needs and expectations[3],[4].

The aim of the PhD proposal is to determine whether feed diversity can represent an enrichment for ruminants, using sheep as main model, and addressing the sensory, nutritional and occupational dimensions of feeding enrichment. The questions are 1- to assess whether gestating ewes are able to benefit from dietary diversity to improve their welfare and/or health, via the selection of the appropriate diet relative to their individual needs; 2- to investigate how the different dimensions of enrichment are involved; 3- to test the concept of feeding pleasure (hedonism) related to the diversity of feeds’ sensory characteristics.

To this aim, a multidisciplinary approach will be used, with ethology as the principal discipline, complemented with nutrition, nutrigenomics, immunity, metabolism, digestive microbiology, neurobiology, and milk and feed quality. Sheep will be the model of interest (gestating ewes and their lambs), even if the rodent model (mice) will likely be preferred for neurological measurements. The PhD project will be based on experiments proposing different feed or sensory diversities. The PhD student will benefit from the multidisciplinary partnership of the supporting projects. Complementarily, the PhD student will have the opportunity to participate in some works with the international partner at his laboratory.

[1]https://www.eurcaw-ruminants-equines.eu/welfare_topics/enrichment/ ; https://liftanimalwelfare.eu/

[2] Duncan AJ, Ginane C, Gordon IJ, Ørskov ER. 2003. Why do herbivores select mixed diets? In VIth Int. Symp. Nutr. Herb. p.195–209.

[3] Beck MR, Gregorini P. 2020. How dietary diversity enhances hedonic and eudaimonic well-being in grazing ruminants. Front Vet Sci 7:1–14.

[4] Leiber F, Walkenhorst M, Holinger M. 2020. The relevance of feed diversity and choice in nutrition of ruminant livestock. Landbauforschung J Sustain and Org Agric Syst 70:35–38