Effects of maternal plane of nutrition and increased dietary selenium in first-parity ewes on inflammatory response in the ovine neonatal gut

Many areas of the western UnitedStates have soils that have increased Se content, andruminants grazing these rangelands may ingest increasedquantities of Se. In addition, high-energy dietsor increased Se intake may induce gut inflammation.The objective of this study was to evaluate the effectsof maternal plane of nutrition and increased dietary Seduring gestation on inflammatory responses in neonatallamb ileal tissue, a major immune organ. Rambouilletewes (age = 240 ± 17 d; initial BW = 52.1 ± 6.2 kg)were allocated to 4 treatments arranged in a 2 × 2 factorial.Factors included Se [adequate Se (ASe, 11.5 μg/kg of BW) or high Se (HSe, 77.0 μg/kg of BW)] initiatedat breeding, and nutritional plane [100% (CON)or 140% (HIH) of requirements] initiated at d 40 of gestation.Ewes were fed individually from d 40, and lambswere removed at parturition and fed artificial colostrumand milk replacer. Lambs were necropsied at 20 d ofage, and ileal tissues were sampled for immunoblottingand real-time quantitative reverse-transcription PCRanalyses. The ASe-HIH and HSe-CON treatments hadno effect (P = 0.179) on inflammatory signaling comparedwith ASe-CON. However, greater inflammatorysignaling was detected in the HSe-HIH group, as shownby increased (P < 0.05) mRNA expression of tumornecrosis factor-α and chemotaxis IL-8. Consistently,phosphorylation of c-Jun N-terminal kinase, a primaryinflammatory signaling mediator, was greater (P <0.05) in the HSe-HIH group compared with other treatments.Consistent with cytokine expression, mast celldensity was less in the HSe-CON group than in othertreatments. The expression of transforming growth factorβ mRNA was greater (P < 0.05) in the HSe-HIHgroup; consistently, collagen content was increasedin the HSe-HIH group compared with the ASe-CONgroup (P < 0.05). In conclusion, independently, neitherHSe nor HIH had major effects on inflammation, butin combination, these maternal treatments induced aninflammatory response in the neonatal intestine.