title: Prepartum feeding level and body condition score affect immunological performance in grazing dairy cows during the transition period.
abstract: Precalving feeding level affects dry matter intake, postcalving energy balance, the risk of hepatic lipidosis and metabolic disease, and gene expression in liver and adipose tissue. These coincide with a higher risk of disease postpartum and, very likely, a failure to reach optimum production as well as reproductive targets. Current interpretation of the available evidence suggest that metabolic stressors affect the immune system of transition dairy cows and lead to reduced immunocompetence. The objective of the current study was to investigate the effect of precalving body condition score (BCS) and level of feeding on immunocompetence during the peripartum period. Twenty-three weeks before calving, 78 cows were allocated randomly to 1 of 6 treatment groups (n=13) in a 2 × 3 factorial arrangement: 2 precalving BCS categories (4.0 and 5.0, based on a 10-point scale) and 3 levels of energy intake during the 3 wk preceding calving (75, 100, and 125% of estimated requirements). Blood was sampled precalving and at 1, 2 and 4 wk after calving. Cells were analyzed by flow cytometry and quantitative real-time PCR. The numbers of T helper lymphocytes (CD4+), cytotoxic T lymphocytes (CD8+), natural killer cells (CD335+), and γδ T lymphocytes (WC1+) as well as their activation status [IL-2 receptor (CD25)+ cells] were highly variable between animals, but there was no evident effect of BCS, feeding level, or time. All groups presented with an increase in expression of cytokines in unstimulated blood cells in the week after calving, although this was significant only for IFNG in the BCS 4.0 group. Analysis of in vitro-stimulated cells allowed 2 general observations: (1) cows with high energy intake precalving (125%) had increased cytokine expression precalving, and (2) all cows had increased cytokine expression in the week after calving. The present study provides evidence that prepartum feed management can affect immunocompetence during the transition period. Considering the current results, optimally conditioned animals might benefit from a restricted precalving diet, whereas underconditioned cows can be fed to requirements.
authors.affiliation: AgResearch, Hopkirk Research Institute, Grasslands Research Centre, Palmerston North, New Zealand 4442.
authors.forename: Joshua
authors.initials: J
authors.lastname: Lange
authors.affiliation: AgResearch, Hopkirk Research Institute, Grasslands Research Centre, Palmerston North, New Zealand 4442.
authors.forename: Allison
authors.initials: A
authors.lastname: McCarthy
authors.affiliation: DairyNZ Limited, Private Bag 3221, Hamilton, New Zealand 3240.
authors.forename: Jane
authors.initials: J
authors.lastname: Kay
authors.affiliation: DairyNZ Limited, Private Bag 3221, Hamilton, New Zealand 3240.
authors.forename: Susanne
authors.initials: S
authors.lastname: Meier
authors.affiliation: DairyNZ Limited, School of Biological Sciences, University of Auckland, New Zealand 1010.
authors.forename: Caroline
authors.initials: C
authors.lastname: Walker
authors.affiliation: DairyNZ Limited, School of Biological Sciences, University of Auckland, New Zealand 1010.
authors.forename: Mallory A
authors.initials: MA
authors.lastname: Crookenden
authors.affiliation: University of Queensland, Centre for Clinical Research, Royal Brisbane and Women's Hospital Campus, Herston, Queensland 4029, Australia.
authors.forename: Murray D
authors.initials: MD
authors.lastname: Mitchell
authors.affiliation: Department of Animal Sciences, University of Illinois, Urbana 61801.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Loor
authors.affiliation: DairyNZ Limited, Private Bag 3221, Hamilton, New Zealand 3240.
authors.forename: John R
authors.initials: JR
authors.lastname: Roche
authors.affiliation: AgResearch, Hopkirk Research Institute, Grasslands Research Centre, Palmerston North, New Zealand 4442. Electronic address: axel.heiser@agresearch.co.nz.
authors.forename: Axel
authors.initials: A
authors.lastname: Heiser
mesh_terms: D000818:Animals; D001823:Body Composition; D002417:Cattle / Q000276:immunology / Q000502:physiology*; D003612:Dairying; D005247:Feeding Behavior; D005260:Female; D007121:Immunocompetence; D058725:Peripartum Period
keywords: immunity; immunocompetence; peripartum period; transition cow