Genetic selection for resistance to mycoplasmal pneumonia of swine (MPS) in the Landrace line influences the expression of soluble factors in blood after MPS vaccine sensitization

Abstract

We recently developed a Landrace line that is resistant to mycoplasmal pneumonia of swine (MPS) infection by genetic selection for five generations, and we reported that the immunophenotype of this line is different from that of the non-selected line in terms of changes in peripheral blood leukocyte population after MPS vaccination. This study followed up previous findings demonstrating changes in soluble factors in blood, namely, hormones, Mycoplasma hyopneumoniae-specific immunoglobulin G (IgG), and cytokines. These two lines were injected with MPS vaccine on days -7 and 0 after blood sampling on those days, and blood samples were collected on days -14, -7, 0, 2, 7 and 14. We found changes in the levels of many hormones and cytokines in both lines. However, we found that only growth hormone (GH) and interferon (IFN)-γ levels were statistically different between these two lines. GH concentration was reduced (day 0) and IFN-γ concentration was increased (day 14) in the MPS-selected line compared with the non-selected line, despite unchanged IFN-γ messenger RNA expression in blood cells. Although detailed mechanisms underlying these phenotypes remain unsolved, these traits would be useful to improve MPS resistance in pig production and provide an insight into MPS infection.

Correlated response of peripheral blood cytokines with selection for reduced mycoplasma pneumonia of swine lesions in Landrace pigs

“…However, there are no reports on the relationship between Mhp or MPS and IL-17. The present result, in which increased breeding value of IFN-γ concentration corresponded to decreased breeding value of morbid MPS lesions over five generations is supported by the reported IFN-γ response to vaccination with Mhp (Shimazu et al 2014). Therefore, the strong negative genetic correlation between MPS lesions and IL-17 in the present study represents an important finding.…”

“…The importance of IL-17 in mycoplasmal infection has been reported only for mice (Sieve et al 2009). Shimazu et al (2014) previously reported that IFN-γ concentration in serum after MPS vaccination was significantly higher in the MPS-selected Landrace line compared with a general, non-selected Landrace line. However, an important role of IL-17 in recruitment of the neutrophilic leukocyte in the biophylaxis response to infection is pointed out (Wu et al 2007).…”

“…Selection traits included ADG, backfat thickness (BF), peripheral blood cortisol concentration and morbid MPS lesions (Kadowaki et al 2012). In addition, when the MPS vaccine was inoculated, the increase cytokines such as IFN-γ and IL-10 of the selected group was higher than that in non-selected Landrace pigs (Shimazu et al 2014). In that experiment, the total number of peripheral blood white blood cells (WBC), phagocyte activity (PA), complement alternative pathway activity (CAPA), granular leukocyte and lymphocytes ratio (GLR), and sheep red blood cell (SRBC)-specific antibody production (AP) were measured at approximately 105 kg body weight (BW), and breeding values were estimated.…”

Genetic resistance - an alternative for controlling PRRS?

“…However, the search for significant and applicable gene variants has developed into an ever-expanding and successful branch of clinical research, including viral (Pseudorabiesvirus [88]; Influenza A (e.g. [143]); bacterial (Haemophilus parasuis [131]; Actinobacillus pleuropneumoniae [93,94]; Mycoplasma hyopneumoniae (e.g., [108]); Streptococcus suis [136]) and parasitic diseases (Sarcocystis [89]; Ascaris suum [100,101]). More than 2,500 quantitative trait loci (QTL) have been published for health parameters in the pig, among them 400 for resistance/susceptibility against a broad range of pathogens (http://www.animalgenome.org/QTLdb/; current status: October 2016).…”

Mycoplasma pneumonia of swine (MPS) resistance and immune characteristics of pig lines generated by crossing an MPS pulmonary lesion selected Landrace line and a highly immune capacity selected Large White line

“…hyopneumoniae vaccine sensitization (Shimazu et al . , ). The Research and Development Center, Nippon Meat Packers Inc., Japan, improved the Large White breed by selecting for higher peripheral blood immunity over six generations.…”