V. Myllys et al., EFFECT OF ABRASION OF TEAT ORIFICE EPITHELIUM ON DEVELOPMENT OF BOVINE STAPHYLOCOCCAL MASTITIS, Journal of dairy science, 77(2), 1994, pp. 446-452
The predisposing effect of teat damage on mastitis caused by staphyloc
occi and the pathogenicity of Staphylococcus aureus, Staphylococcus hy
icus, and Staphylococcus epidermidis were investigated with an experim
ental model. The study included three experiments in which the teat ca
nal orifice of 5 cows was slightly abraded. Experimental and control q
uarters were challenged with a staphylococcal suspension, and the stat
us of the quarters was monitored. Virulence of the staphylococcal stra
ins was studied using a protein-binding test with I-125-labeled protei
ns (fibronectin, fibrinogen, vitronectin, collagen type I and II, and
IgG). Abrasion on the teat orifice epithelium was a predisposing facto
r for staphylococcal infections. Teat canal infection or colonization
developed in 93% of experimental quarters and in 53% of control quarte
rs; IMI developed in 73% of experimental quarters, but in none of the
control quarters. Quarter IMI developed more consistently when the con
taminating agent was S. aureus. Staphylococcus hyicus was very effecti
ve in causing teat canal infections, but S. epidermidis appeared to be
less infectious. The S. aureus strain had strong binding sites for mo
st of the proteins tested. The S. hyicus and S. epidermidis strains sh
owed no binding, or only very weak binding, which correlated with lowe
r infection rates.