Specificity of the anti-inflammatory effect of a staphylococcal cell wall extract in the bovine udder

The cell wall of Staphylococcus aureus (strains 21 and Glaxo) was treated with deoxycholate and the insoluble residue was solubilised with lysozyme. The effect of the extract in modulating the inflammatory response due to infection of the lactating bovine udder was evaluated. Cows were infected with S. aureus strain 21 or Streptococcus agalactiae, with or without the cell wall extracts. The clinical response to infection was assessed, and milk samples collected up to 30 h were assayed for antitrypsin and NAGase levels, somatic cell count, and for the ability of whey to support bacterial growth. The extracts markedly reduced the inflammatory response elicited by both S. aureus and S. agalactiae, indicating the effect was non-specific. The extract from strain 21 was generally more effective than that from strain Glaxo.