|Springer, Haley - IOWA STATE UNIVERSITY|
Submitted to: Journal of Dairy Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 29, 2008
Publication Date: August 1, 2008
Citation: Bannerman, D.D., Springer, H.R., Paape, M.J., Kauf, A.C., Goff, J.P. 2008. Evaluation of breed-dependent differences in the innate immune responses of Holstein and Jersey cows to Staphylococcus aureus intramammary infection. Journal of Dairy Research. 75:291-301. Interpretive Summary: Mastitis is a leading health problem of dairy cows. Breed-dependent differences in the prevalence of this disease have been reported in various surveys. Because the rapidity and nature of the innate immune response influences the ability of the host to eradicate infections, breed-dependent differences in the innate immune response during experimentally-induced Staphylococcus aureus mastitis were investigated in the two most populous U.S. dairy breeds, Holstein and Jersey cows. The onset, duration and overall magnitude of the innate immune responses evaluated were similar between breeds. Thus, the findings from this study indicate that the innate immune response of Holstein and Jersey cows to Staphylococcus aureus intramammary infection is highly conserved.
Technical Abstract: Mastitis is one of the most prevalent diseases of cattle. Various studies have reported breed-dependent differences in the risk for developing this disease. Among two major breeds, Jersey cows have been identified as having a lower prevalence of mastitis than Holstein cows. It is well established that the nature of the initial innate immune response to infection influences the ability of the host to clear harmful bacterial pathogens. Whether differences in the innate immune response to intramammary infections explain, in part, the differential prevalence of mastitis in Holstein and Jersey cows remains unknown. The objective of the current study was to evaluate several parameters of the innate immune response of Holstein and Jersey cows to intramammary infection with Staphylococcus aureus, a common mastitis-inducing pathogen. To control for non-breed related factors that could influence these parameters, all cows were of the same parity, in similar stages of milk production, housed and managed under identical conditions, and experimentally infected and sampled in parallel. The following parameters of the innate immune response were evaluated: acute phase protein synthesis of serum amyloid A and lipopolysaccharide-binding protein; total and differential circulating white blood cell counts; milk somatic cell counts; mammary vascular permeability; milk N-acetyl-beta-D-glucosaminidase (NAGase) activity; and production of the cytokines, interferon (IFN)-gamma, interleukin (IL)-12, tumor growth factor(TGF)-alpha, and TGF-beta1. The temporal response of all of these parameters following infection was similar between Holstein and Jersey cows. Further, with the exception of changes in circulating neutrophils and NAGase activity, the overall magnitude of these parameters were also comparable. Together, these data demonstrate that the innate immune response of Holstein and Jersey cows to S. aureus intramammary infection remains highly conserved despite previously reported differences in mastitis prevalence, as well as genotypic and phenotypic traits, that exist between the two breeds.