Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/7/2016
Publication Date: 12/8/2017
Citation: Sanchez, N.C., Carroll, J.A., Arthington, J.D., Lancaster, P.A. 2017. Exposure to lipopolysaccharide in utero alters the postnatal metabolic response in heifers. Journal of Animal Science. 95:5176-5183.

Interpretive Summary: Prenatal stress has been demonstrated to influence various aspects of the postnatal stress and immune response. However, there are limited prenatal stress studies that utilize cattle as the model, none of which have directly evaluated the potential effects of prenatal immune stimulation. As cattle are exposed to stressors and immune challenges throughout the production cycle, not excluding gestation, it is necessary to gain a better understanding of the effects of prenatal stress and prenatal immune stimulation on the offspring. Metabolism plays a major role in the ability of the immune system to successfully clear pathogen(s). While often overlooked, a significant amount of energy is necessary for immune activation and function. Therefore, this study was designed to determine if prenatal exposure to lipopolysaccharide alters the postnatal metabolic response to a postnatal lipopolysaccharide challenge in beef heifers. Data from this study demonstrate that prenatal lipopolysaccharide exposure alters several aspects of the stress and metabolic responses to postnatal challenge. Specifically, heifers prenatally challenged with lipopolysaccharide produced an increased and extended stress response, reduced glucose and free fatty acid response, and elevated urea nitrogen response. These data suggest that prenatal lipopolysaccharide exposure may have resulted in changes in energy storage depots or may have changed the manner that energy is redistributed or partitioned in response to an immune challenge. This information will be of interest to producers and scientists working in the field of beef cattle health and management.

Technical Abstract: This study was designed to determine the effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal metabolic response to an LPS challenge in beef heifers. Pregnant crossbred cows (n = 50) were assigned to a prenatal immune stimulation (PIS; n = 25; administered 0.1 micrograms/kg BW LPS subcutaneously 233 +/- 15d of gestation) or saline treatment group (Control; n = 25). Birth and weaning weights of calves were collected. There was not (P > 0.05) a treatment × gender interaction for birth weight or 205-d adjusted weaning weight. Treatment did not affect (P > 0.05) birth weight, but steers and heifers of PIS cows had greater (P < 0.02) 205-d adjusted weaning weight than offspring from Control cows. From the two prenatal treatment groups, heifer calves (n = 12 PIS and 11 Control) were identified at weaning (238 +/- 15d of age) to subsequently receive an LPS challenge. On d 0, heifers were fitted with indwelling jugular catheters and were moved into individual pens. On d 1, heifers (fed at 0600h) were challenged i.v. with LPS (0.5 micrograms/kg BW) at 0 h (1000h). Blood samples were collected at 30-min intervals from -2 to 8 h and again at 24 h relative to the LPS challenge. There was a treatment × time interaction (P < 0.001) for cortisol such that PIS heifers had greater cortisol from 4 to 6.5 h post-LPS challenge (P < 0.001). There was a treatment x time interaction (P = 0.04) for serum glucose such that glucose was greater (P = 0.01) in PIS than Control heifers at 0.5 h but was greater in Control than PIS heifers at 2, 4.5, and 7 h post-LPS challenge. This resulted in overall time (P < 0.001) and treatment (P = 0.001) effects such that Control heifers had greater glucose concentrations than PIS heifers. There was a tendency (P = 0.10) for a treatment x time interaction for serum NEFA, such that NEFA was greater in Control than PIS heifers at -2, -1.5, and 7 h relative to the LPS challenge (P = 0.02). Also, there were time (P < 0.001) and treatment effects (P = 0.002) for NEFA with Control heifers having greater NEFA than PIS heifers. Serum BUN was affected by a treatment × time interaction (P = 0.002). Concentrations of BUN were greater in PIS heifers from -1.5 to -1 h, 1 to 2 h, at 4 h, and from 5 to 24 h relative to the LPS challenge. These results demonstrate that postnatal growth and the metabolic response of weaned beef calves can be significantly altered with a single exposure to LPS in utero.