The effect of a Staphylococcal cell wall factor on the early inflammatory response to Staphylococcal infection of the lactating bovine udder

The effect on the early inflammatory response in the bovine mammary gland of a factor extracted from the cell wall of Staphylococcus aureus was studied. The insoluble factor was extracted from a 3h‐culture, and was mixed with S. aureus from an overnight culture (OF) for experimental infection of a lactating quarter. Other quarters were infected with a 3h or an overnight culture (O). Five cows were used in the experiment. The O‐quarters showed more severe clinical signs than seen in the 3h‐and OF quarters. Antitrypsin levels and NAGase concentrations were much reduced in the 3h‐and OF‐quarters. While the cell wall factor profoundly reduced the early inflammatory response, the effect on the final outcome of the infection was not determined.