| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Ghent University, Faculty of Veterinary Medicine, Department of Physiology, Biochemistry and Biometrics, Salisburylaan 133, B-9820 Merelbeke, Belgium
Corresponding author: C. Burvenich; e-mail: christian.burvenich{at}ugent.be.
To study the host-pathogen interactions during Escherichia coli mastitis, we first determined whether E. coli infection would change blood and milk polymorphonuclear neutrophil (PMN) chemiluminescence (CL) and viability. We then hypothesized that when E. coli invade the mammary gland, the viable PMN in milk would efficiently phagocytose and destroy E. coli before establishment of infection. We observed that the phagocytosis-dependent and independent CL were closely linked to PMN viability and were crucial to the outcome of mastitis. Maximal PMN influx and colony-forming units in infected quarters appeared at postinfection hours (PIH) 6 to 24. This further boosted PMN recruitment through bone marrow-blood barrier as well as blood-milk barrier. The survival of recruited PMN in the E. coli-infected quarters was much higher than that of noninfected quarters. Chemiluminescence activity of PMN from the infected quarters significantly increased following E. coli infection, even exceeding that of blood at PIH 6, 12, and 18 to 24; no such increase was observed in noninfected quarters, suggesting that the various responses of milk PMN to stimuli resulted largely from PMN viability. The highest CL intensity and durability was observed in milk PMN from infected quarters at PIH 12. Whereas an increased viability of PMN in the noninfected quarters was only significant at PIH 6, the viability of PMN in infected quarters was long lasting and significantly higher at PIH 6 to 72. Importantly, higher preinfection milk PMN viability correlated with bacterial clearance, which was accompanied by faster recovery. Our study strongly supports the hypothesis that boosting milk PMN viability could be a strategy with which to prevent or reduce the severity of coliform mastitis in dairy cows. This strategy might be achieved through strengthening bone marrow functionality.
Key Words: Escherichia coli mastitis • neutrophil • severity • viability
Abbreviation key: AUC = area under the curve, CL = chemiluminescence, MP = daily milk production, PIH = postinfection hour, PMA = phorbol 12-myristate 13-acetate, PMN = polymorphonuclear neutrophil, ROS = reactive oxygen species.
This article has been cited by other articles:
|
|
 |
|
  S. L. Moya, M. A. Gomez, L. A. Boyle, J. F. Mee, B. O'Brien, and S. Arkins Effects of Milking Frequency on Phagocytosis and Oxidative Burst Activity of Phagocytes from Primiparous and Multiparous Dairy Cows During Early Lactation J Dairy Sci, February 1, 2008; 91(2): 587 - 595. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Mehrzad, D. Janssen, L. Duchateau, and C. Burvenich Increase in Escherichia coli Inoculum Dose Accelerates CD8+ T-Cell Trafficking in the Primiparous Bovine Mammary Gland J Dairy Sci, January 1, 2008; 91(1): 193 - 201. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Burvenich, D. D. Bannerman, J. D. Lippolis, L. Peelman, B. J. Nonnecke, M. E. Kehrli Jr., and M. J. Paape Cumulative Physiological Events Influence the Inflammatory Response of the Bovine Udder to Escherichia coli Infections During the Transition Period J Dairy Sci, June 1, 2007; 90(13_suppl): E39 - E54. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Scalia, N. Lacetera, U. Bernabucci, K. Demeyere, L. Duchateau, and C. Burvenich In Vitro Effects of Nonesterified Fatty Acids on Bovine Neutrophils Oxidative Burst and Viability J Dairy Sci, January 1, 2006; 89(1): 147 - 154. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
