. Schwartz-cornil, We thank G. Lepape for his expertise in statistical analyses of our data. We are grateful to A. Souriau, N. Bernardet and F. Meurens for their help with qRT-PCR. We thank the group of Contrôle et Immunologie des Maladies Entériques du Nouveau-Né in Nouzilly. We thank J. C. Hope for supplying anti-bovine CD80, CD86, CD40, SIRP-a and CD26 mAbs, and S. Wattergedera for providing recombinant ovine cytokines developed by the

G. J. Randolph, Migratory dendritic cells: sometimes simply ferries?, Immunity, vol.25, pp.15-18, 2006.

W. R. Heath and F. R. Carbone, Dendritic cell subsets in primary and secondary T cell responses at body surfaces, Nat Immunol, vol.10, pp.1237-1244, 2009.

E. Segura and J. A. Villadangos, Antigen presentation by dendritic cells in vivo, Curr Opin Immunol, vol.21, pp.105-110, 2009.

R. S. Allan, C. M. Smith, G. T. Belz, A. L. Van-lint, and L. M. Wakim, Epidermal viral immunity induced by CD8alpha+ dendritic cells but not by Langerhans cells, Science, vol.301, pp.1925-1928, 2003.

R. S. Allan, J. Waithman, S. Bedoui, C. M. Jones, and J. A. Villadangos, Migratory dendritic cells transfer antigen to a lymph node-resident dendritic cell population for efficient CTL priming, Immunity, vol.25, pp.153-162, 2006.

Y. He, J. Zhang, C. Donahue, L. D. Falo, and J. , Skin-derived dendritic cells induce potent CD8(+) T cell immunity in recombinant lentivector-mediated genetic immunization, Immunity, vol.24, pp.643-656, 2006.

E. J. Allenspach, M. P. Lemos, P. M. Porrett, L. A. Turka, and T. M. Laufer, Migratory and lymphoid-resident dendritic cells cooperate to efficiently prime naive CD4 T cells, Immunity, vol.29, pp.795-806, 2008.

A. M. Mount, C. M. Smith, F. Kupresanin, K. Stoermer, and W. R. Heath, Multiple dendritic cell populations activate CD4+ T cells after viral stimulation, PLoS One, vol.3, p.1691, 2008.

J. A. Villadangos and P. Schnorrer, Intrinsic and cooperative antigen-presenting functions of dendritic-cell subsets in vivo, Nat Rev Immunol, vol.7, pp.543-555, 2007.

U. Yrlid and M. J. Wick, Antigen presentation capacity and cytokine production by murine splenic dendritic cell subsets upon Salmonella encounter, J Immunol, vol.169, pp.108-116, 2002.

H. K. Lee, M. Zamora, M. M. Linehan, N. Iijima, and D. Gonzalez, Differential roles of migratory and resident DCs in T cell priming after mucosal or skin HSV-1 infection, J Exp Med, vol.206, pp.359-370, 2009.

S. Bedoui, P. G. Whitney, J. Waithman, L. Eidsmo, and L. Wakim, Crosspresentation of viral and self antigens by skin-derived CD103+ dendritic cells, Nat Immunol, vol.10, pp.488-495, 2009.

I. Gohin, M. Olivier, I. Lantier, M. Pepin, and F. Lantier, Analysis of the immune response in sheep efferent lymph during Salmonella abortusovis infection, Vet Immunol Immunopathol, vol.60, pp.111-130, 1997.
URL : https://hal.archives-ouvertes.fr/hal-02686939

R. Bujdoso, G. Harkiss, J. Hopkins, and I. Mcconnell, Afferent lymph dendritic cells: a model for antigen capture and presentation in vivo, Int Rev Immunol, vol.6, pp.177-186, 1990.

S. Ryan, L. Tiley, I. Mcconnell, and B. Blacklaws, Infection of dendritic cells by the Maedi-Visna lentivirus, J Virol, vol.74, pp.10096-10103, 2000.

F. Pascale, V. Contreras, M. Bonneau, A. Courbet, and S. Chilmonczyk, Plasmacytoid dendritic cells migrate in afferent skin lymph, J Immunol, vol.180, pp.5963-5972, 2008.
URL : https://hal.archives-ouvertes.fr/hal-01193693

V. Contreras, C. Urien, R. Guiton, Y. Alexandre, and T. P. Vu-manh, Existence of CD8alpha-like dendritic cells with a conserved functional specialization and a common molecular signature in distant mammalian species, J Immunol, vol.185, pp.3313-3325, 2010.

S. S. Chan, P. Mastroeni, I. Mcconnell, and B. A. Blacklaws, Salmonella infection of afferent lymph dendritic cells, J Leukoc Biol, vol.83, pp.272-279, 2008.

M. Bonneau, M. Epardaud, F. Payot, V. Niborski, and M. I. Thoulouze, Migratory monocytes and granulocytes are major lymphatic carriers of Salmonella from tissue to draining lymph node, J Leukoc Biol, vol.79, pp.268-276, 2006.
URL : https://hal.archives-ouvertes.fr/hal-02666924

M. De-veer, J. Kemp, J. Chatelier, M. J. Elhay, and E. N. Meeusen, The kinetics of soluble and particulate antigen trafficking in the afferent lymph, and its modulation by aluminium-based adjuvant, Vaccine, vol.28, pp.6597-6602, 2010.

F. Lantier, P. Pardon, and J. Marly, Vaccinal properties of Salmonella abortus ovis mutants for streptomycin: screening with a murine model, Infect Immun, vol.34, pp.492-497, 1981.

I. Schwartz-cornil, M. Epardaud, and M. Bonneau, Cervical duct cannulation in sheep for collection of afferent lymph dendritic cells from head tissues, Nat Protoc, vol.1, pp.874-879, 2006.
URL : https://hal.archives-ouvertes.fr/hal-02662326

J. Hellemans, G. Mortier, A. De-paepe, F. Speleman, and J. Vandesompele, qBase relative quantification framework and software for management and automated analysis of real-time quantitative PCR data, Genome Biol, vol.8, p.19, 2007.

L. Lei and J. M. Hostetter, Limited phenotypic and functional maturation of bovine monocyte-derived dendritic cells following Mycobacterium avium subspecies paratuberculosis infection in vitro, Vet Immunol Immunopathol, vol.120, pp.177-186, 2007.

L. G. Pedersen, Y. Castelruiz, S. Jacobsen, and B. Aasted, Identification of monoclonal antibodies that cross-react with cytokines from different animal species, Vet Immunol Immunopathol, vol.88, pp.111-122, 2002.

J. C. Hope, L. S. Kwong, M. Thom, P. Sopp, and W. Mwangi, Development of detection methods for ruminant interleukin (IL)-4, J Immunol Methods, vol.301, pp.114-123, 2005.

V. Suraud, I. Jacques, M. Olivier, and L. A. Guilloteau, Acute infection by conjunctival route with Brucella melitensis induces IgG+ cells and IFN-gamma producing cells in peripheral and mucosal lymph nodes in sheep, Microbes Infect, vol.10, pp.1370-1378, 2008.
URL : https://hal.archives-ouvertes.fr/hal-02662763

E. Brunner, S. Domhof, and F. Langer, Nonparametric analysis of longitudinal data in factorial experiments, 2002.

M. Epardaud, M. Bonneau, F. Payot, C. Cordier, and J. Megret, Enrichment for a CD26hi SIRP-a subset in lymph dendritic cells from the upper aero-digestive tract, J Leukoc Biol, vol.76, pp.553-561, 2004.
URL : https://hal.archives-ouvertes.fr/hal-02683232

M. L. Del-rio, G. Bernhardt, J. I. Rodriguez-barbosa, and R. Forster, Development and functional specialization of CD103+ dendritic cells, Immunol Rev, vol.234, pp.268-281, 2010.

C. P. Akesson, L. Mc, A. Espenes, and M. Aleksandersen, Phenotypic characterisation of intestinal dendritic cells in sheep, Dev Comp Immunol, vol.32, pp.837-849, 2008.

C. R. Mackay, W. L. Marston, L. Dudler, O. Spertini, and T. F. Tedder, Tissue-specific migration pathways by phenotypically distinct subpopulations of memory T cells, Eur J Immunol, vol.22, pp.887-895, 1992.

F. Geissmann, M. G. Manz, S. Jung, M. H. Sieweke, and M. Merad, Development of monocytes, macrophages, and dendritic cells, Science, vol.327, pp.656-661, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00502972

M. Norimatsu, V. Chance, G. Dougan, C. J. Howard, and B. Villarreal-ramos, Live Salmonella enterica serovar Typhimurium (S. Typhimurium) elicit dendritic cell responses that differ from those induced by killed S. Typhimurium, Vet Immunol Immunopathol, vol.98, pp.193-201, 2004.

H. W. Mittrucker and S. H. Kaufmann, Immune response to infection with Salmonella typhimurium in mice, J Leukoc Biol, vol.67, pp.457-463, 2000.

M. Cagiola, G. Severi, K. Forti, M. Menichelli, and P. Papa, Abortion due to Salmonella enterica serovar Abortusovis (S. Abortusovis) in ewes is associated to a lack of production of IFN-gamma and can be prevented by immunization with inactivated S. Abortusovis vaccine, Vet Microbiol, vol.121, pp.330-337, 2007.

L. A. Guilloteau, K. Laroucau, M. Olivier, M. J. Grillo, and C. M. Marin, Residual virulence and immunogenicity of CGV26 and CGV2631 B. melitensis Rev. 1 deletion mutant strains in sheep after subcutaneous or conjunctival vaccination, Vaccine, vol.24, pp.3461-3468, 2006.
URL : https://hal.archives-ouvertes.fr/hal-02658038