Pig enrichment affects immune response to disease

Effect of enriched housing on levels of natural (auto-)antibodies in pigs co-infected with porcine reproductive and respiratory syndrome virus (PRRSV) and Actinobacillus pleuropneumoniae.
Lu Luo, Ingrid Daniƫlle Ellen van Dixhoorn, Inonge Reimert, Bas Kemp, Jantina Elizabeth Bolhuis and Hendrik Karel Parmentier 2017. Vet Res (2017) 48:75.

Abstract

Housing of pigs in barren, stimulus-poor housing conditions may influence their immune status, including antibody
responses to (auto-)antigens, and thus affect immune protection, which will influence the onset and outcome of
infection. In the present study, we investigated the effects of environmental enrichment versus barren housing on the
level of natural (auto-)antibodies (NA(A)b) and their isotypes (IgM and IgG) binding keyhole limpet hemocyanin (KLH),
myelin basic protein (MBP), and phosphorycholine conjugated to bovine serum albumin (PC-BSA) in pigs co-infected
with porcine reproductive and respiratory syndrome virus (PRRSV ) and Actinobacillus pleuropneumoniae (A. pleuro-pneumoniae). Pigs (n= 56) were housed in either barren or enriched pens from birth to 54 days of age. They were infected with PRRSV on 44 days of age, and with A. pleuropneumoniae 8 days later. Blood samples were taken on 7 dif-ferent sampling days. Housing significantly affected the overall serum levels of NA(A)b binding KLH, MBP and PC-BSA, and before infection barren housed pigs had significantly higher levels of NA(A)b than enriched housed pigs, except for KLH-IgM and PC-BSA-IgG. Infection only affected the IgM, but not the IgG isotype. Moreover, changes in MBP-IgM and PC-BSA-IgM following infection were different for enriched and barren housed pigs. These results suggest that the effect of infection on NA(A)b is influenced by housing conditions and that NA(A)b, especially IgM may be affected by infection.