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Last update: May 2021

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Evaluation of compromises between food efficiency, growth and immune activity in laying hen experimental lines

@INRAE C. Maître - Graphe T. Zerjal Légende : Representation of resource allocation trade-offs that distribute limited resources, here represented with the orange sphere, among various competing functions, represented by the blue spheres.
All organisms are inherently constrained by the resources available to them and must therefore allocate these resources among competing functions. This idea is central to the concept of trade-offs, which represent the costs incurred when a change in one trait results in an adverse change in another. Although the environment of domesticated animals is more controlled than that of wild species, particularly with respect to food resources, intensive selection for food production and efficiency can unintentionally trigger negative effects on other fundamental functions, such as immune response, which can lead to adverse effects on animal health and welfare.

In all organisms, life history traits are constrained by trade-offs, which may represent physiological limitations or be related to energy resource management. To detect trade-offs in a population, a promising approach is the use of artificial selection, because intensive selection on one trait can induce unplanned changes in others.
In chickens, breeding companies have made remarkable genetic advances in production and feed efficiency over the past 60 years. However, these advances may have come at the expense of other important biological functions, such as immunity.
In the present study, we used three experimental lines of laying hens-two that were divergently selected for feed efficiency and one that was selected for enhanced antibody response to inactivated Newcastle disease virus (ND3)-to explore the impact of improved feed efficiency on animal immunocompetence and, vice versa, the impact of improved antibody response on animal growth and feed efficiency.

Differences were observed between low (R+) and high (R-) feed efficiency lines with respect to vaccine-specific antibody responses and the number of monocytes, heterophils and/or T cells. The ND3 line exhibited reduced body weight and feed intake compared to the control line, a better antibody response against a set of commercial viral vaccines, but a lower number of leukocytes in the blood.
This study demonstrates the value of using experimental lines divergently selected for feed efficiency or high antibody production to study the modulation of immune parameters in relation to growth and feed efficiency.
Our results provide further evidence that long-term selection for trait improvement may have consequences on other important biological functions. Therefore, strategies to ensure optimal trade-offs between competing functions will ultimately be required in multi-trait selection programs in farm animals

  • Contact : Tatiana Zerjal, équipe GiBBS

See also


Zerjal, T., Härtle, S., Gourichon, D. et al. Assessment of trade-offs between feed efficiency, growth-related traits, and immune activity in experimental lines of layer chickens. Genet Sel Evol 53, 44 (2021).