Evaluation of the use of prenatal immune stimulation to alter postnatal immune function in weaned pigs

Authors: Sanchez, Nicole; MITCHELL, TY - Texas Tech University; Broadway, Paul; BOWEEN, BROOKE - Texas Tech University; DAVIS, EMILY - Texas Tech University; DOBBINS, THOMAS - Texas Tech University; BARKER, SAMANTHA - Texas Tech University; LEGAKO, JERRAD - Texas Tech University; PETRY, AMY - University Of Missouri; Carroll, Jeffery

Submitted to: Frontiers in Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/13/2024
Publication Date: 11/6/2025
Citation: Sanchez, N.C., Mitchell, T.M., Broadway, P.R., Boween, B.M., Davis, E.M., Dobbins, T.W., Barker, S.N., Legako, J.F., Petry, A.L., Carroll, J.A. 2025. Evaluation of the use of prenatal immune stimulation to alter postnatal immune function in weaned pigs. Frontiers in Animal Science. 101(3). https://doi.org/10.1093/jas/skad281.078.
DOI: https://doi.org/10.1093/jas/skad281.078

Interpretive Summary: One area of swine production where large improvements can be made is in swine health. While the industry has benefited from improvements in the areas of vaccines, nutrition, and genetics, there continues to be issues with the overall health of pigs and their susceptibility to disease. One alternative method to improve pig health may be by altering immune responsiveness prior to birth. A study was conducted to determine whether giving a low-dose immune stimulant to sows in the last third of gestation would alter how their piglets responded to the same stimulant after weaning. Results from this study found that giving an immune stimulant to sows in late gestation changed the response of piglets to the same stimulant. These piglets had a quicker fever response and appeared to have reduced inflammation. By changing the immune response of pigs prior to birth, this may better prepare pigs for life after birth. Further, this may have lasting impacts on growth and health. These data will be of interest to researchers in the field of swine health and to swine producers.

Technical Abstract: One area of swine production where large improvements can be made is in swine health. This study was designed to determine whether exposure to low dose endotoxin (lipopolysaccharide; LPS) during gestation can enhance immunity to a subsequent LPS challenge in piglets after weaning. Pregnant Camborough sows (parity: 2.6 ± 1.4) were assigned to prenatal immune stimulation (PIS; n = 7; administered 2.5 µg/kg BW LPS i.m. at d 78 ± 1.8 of gestation) or saline treatment groups (CON; n = 7). From the 2 prenatal treatment groups, barrows (n = 17 PIS, 17 CON) were identified at weaning (21 ± 1.3 d of age) to subsequently receive a post-weaning LPS challenge. On d -7, barrows were transported to the USDA-ARS Livestock Issues Research Unit in Lubbock, TX where they were housed in individual pens in an environmentally controlled building with ad libitum access to water and a starter ration. On d -1, pigs were fitted with indwelling jugular catheters and subcutaneous temperature loggers. On d 0, pigs were challenged i.v. with LPS (10 µg/kg BW) and blood samples were collected at -2, 0, 1, 2, 4, 6, 8, 12, and 24 h relative to LPS challenge. Data were analyzed using PROC MIXED in SAS, specific for repeated measures. There was a treatment × time interaction for subcutaneous temperature (P < 0.01), where temperature increased more quickly at 1 and 2 h post-challenge in PIS compared to CON pigs. There was a tendency (P = 0.08) for less change in white blood cells, relative to baseline values, in PIS compared to CON pigs. There was a treatment × time interaction (P = 0.01) for lymphocyte concentrations where concentrations were reduced in PIS compared to CON pigs at 8 h post-challenge. There was also a treatment × time interaction (P = 0.01) for the change in eosinophil concentrations, where there was less change in eosinophil concentrations from 1 to 12 h in PIS compared to CON pigs. There was a tendency (P = 0.06) for a treatment × time interaction for serum interleukin-6 (IL-6) and IL-8. Granulocyte macrophage colony stimulating factor tended to be greater, and tumor necrosis factor-a tended to be reduced in PIS compared to CON pigs (P = 0.08). These data suggest that exposure to endotoxin in utero can influence the postnatal innate immune response to endotoxin. Thus, it is possible to influence the innate immune response of pigs in utero, which may serve as a method to positively influence postnatal immune responsiveness in a matter that would improve overall health.