title: DNA damage in peripheral blood mononuclear cells and neutrophils of dairy cows during the transition period.
abstract: This study was designed to investigate the apoptotic process in peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophil leukocytes (PMN) in dairy cattle during the transition period. Blood samples were collected from 4 dairy cattle at 3 weeks before the expected parturition (wk -3), parturition (wk 0) and 3 weeks after parturition (wk +3). The DNA damage of PBMC and PMN was evaluated based on the comet assay using visual scoring (arbitrary units). Undamaged DNA remained within the core (score 0) and the broken DNA migrated from the core towards the anode forming the tail of a comet (scores 1-4). Significantly higher scores in PBMC at wk 0 and wk +3 were observed compared with those in PMN although there were no significant changes of scores in either cell type during the experimental period. It is suggested that the apoptotic rate of PBMC is accelerated compared with that of PMC during the transition period.
authors.affiliation: Department of Large Animal Clinical Sciences, School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan ; Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Egypt.
authors.forename: M
authors.initials: M
authors.lastname: Tharwat
authors.affiliation: Department of Veterinary Radiology, School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Endoh
authors.affiliation: Department of Large Animal Clinical Sciences, School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Oikawa
keywords: Apoptosis; Comet assay; Cow; Leukocytes; Transition period