Effect of leukotoxin Mannheimia haemolytica A1 on the inflammatory response in calves.

摘要

The aim of this, study was to estimate the effect of leukotoxin (Lkt) Mannheimia haemolytica A1 on the inflammatory response in calves. The study was performed on 12 clinically healthy, Black and White Lowland breed calves, aged 8 weeks. Each of the experimental animals received a single dose of 25 micro g of Mannheimnia haemolytica A1 Lkt intravenously. The Lkt treated calves were compared with non-treated controls before (0) and 1, 2, 3, 4, 5, 6, 12, 24, 48 and 72 h after the treatment. The following parameters were assayed: concentrations of eicosanoids such as: prostaglandins E₂ and F_{2 alpha} (PGE₂, PGF_{2 alpha} ), thromboxane B₂ (TXB₂) and leukotriene B₄ (LTB₄), as well as selected acute phase proteins (CRP, Cp, Tf, Hp, SAA). The obtained results showed that the concentrations of some acute phase proteins, such as Hp and SA, A and also eicosanoids (PGE₂, PGF_{2 alpha} , TXB₂, LTB₄), were significantly higher in comparison, to the controls especially during the first 3-6 h after the Lkt administration.