title: Effects of precalving body condition and prepartum feeding level on gene expression in circulating neutrophils.
abstract: Extensive metabolic, physiological, and immunological changes are associated with calving and the onset of lactation. As a result, cows transitioning between pregnancy and lactation are at a greater risk of metabolic and infectious diseases. The ability of neutrophils to mount an effective immune response to an infection is critical for its resolution, and increasing evidence indicates that precalving nutrition affects postpartum neutrophil function. The objectives of the current study were to investigate the effect of 2 precalving body condition scores (BCS; 4 vs. 5 on a 10-point scale) and 2 levels of feeding (75 vs. 125% of estimated maintenance requirements) on gene expression in circulating neutrophils. We isolated RNA from the neutrophils of cows (n = 45) at 5 time points over the transition period: precalving (-1 wk), day of calving (d 0), and postcalving at wk 1, 2, and 4. Quantitative reverse transcriptase PCR with custom-designed primer pairs and Roche Universal Probe Library (Roche, Basel, Switzerland) chemistry, combined with microfluidics integrated fluidic circuit chips (96.96 dynamic array), were used to quantify the expression of 78 genes involved in neutrophil function and 18 endogenous control genes. Statistical significance between time points was determined using repeated measures ANOVA with Tukey-Kramer multiple-testing correction to determine treatment effects among weeks. Precalving BCS altered the inflammatory state of neutrophils, with significant increases in overall gene expression of antimicrobial peptides (BNBD4 and DEFB10) and the anti-inflammatory cytokine IL10, and significantly decreased expression of proinflammatory cytokine IL23A in thinner cows (BCS 4) compared with cows calving at BCS 5. Feeding level had a time-dependent effect on gene expression; for example, increased expression of genes involved in leukotriene synthesis (PLA2G4A and ALOX5AP) occurred only at 1 wk postcalving in cows overfed (125% of requirements) precalving compared with those offered 75% of maintenance requirements. Results indicate that precalving body condition and changes in prepartum energy lead to altered gene expression of circulating neutrophils, highlighting the importance of transition cow nutrition for peripartum health.
authors.affiliation: DairyNZ, c/o University of Auckland, 3A Symonds Street, Auckland 1010, New Zealand; Institute of Vet, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand. Electronic address: mallory.crookenden@dairynz.co.nz.
authors.forename: M A
authors.initials: MA
authors.lastname: Crookenden
authors.affiliation: DairyNZ, c/o University of Auckland, 3A Symonds Street, Auckland 1010, New Zealand.
authors.forename: C G
authors.initials: CG
authors.lastname: Walker
authors.affiliation: Institute of Vet, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand; AgResearch, Hopkirk Research Institute, Palmerston North 4442, New Zealand.
authors.forename: A
authors.initials: A
authors.lastname: Heiser
authors.affiliation: Institute of Vet, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand.
authors.forename: A
authors.initials: A
authors.lastname: Murray
authors.affiliation: Institute of Vet, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand.
authors.forename: V S R
authors.initials: VSR
authors.lastname: Dukkipati
authors.affiliation: DairyNZ, Cnr Ruakura and Morrinsville Rds (SH26), Newstead, Hamilton 3284, New Zealand.
authors.forename: J K
authors.initials: JK
authors.lastname: Kay
authors.affiliation: DairyNZ, Cnr Ruakura and Morrinsville Rds (SH26), Newstead, Hamilton 3284, New Zealand.
authors.forename: S
authors.initials: S
authors.lastname: Meier
authors.affiliation: Department of Animal and Avian Sciences, University of Maryland, College Park 20742.
authors.forename: K M
authors.initials: KM
authors.lastname: Moyes
authors.affiliation: University of Queensland, Centre for Clinical Research, Herston, Queensland 4029, Australia.
authors.forename: M D
authors.initials: MD
authors.lastname: Mitchell
authors.affiliation: Department of Animal Sciences, University of Illinois, Urbana 61801.
authors.forename: J J
authors.initials: JJ
authors.lastname: Loor
authors.affiliation: DairyNZ, Cnr Ruakura and Morrinsville Rds (SH26), Newstead, Hamilton 3284, New Zealand.
authors.forename: J R
authors.initials: JR
authors.lastname: Roche
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D007774:Lactation; D008892:Milk; D009504:Neutrophils / Q000276:immunology*; D058725:Peripartum Period; D049590:Postpartum Period; D011247:Pregnancy
keywords: dairy cow; nutrition; peripartum; polymorphonuclear leukocyte