Physiology and management: reduction of acyloxyacyl hydrolase activity in circulating neutrophils from cows after parturition

摘要

Bovine neutrophils contain the enzyme acyloxyacyl hydrolase, which hydrolyzes the acyloxyacyl linkage of the two nonhydroxylated fatty acyl chains to two 3-hydroxy fatty acids in the highly conserved lipid A part of endotoxins with high specificity. This hydroly- sis decreases the toxicity of lipid A, but the im- munostimulatory capacity of endotoxin is largely maintained. In two trials, we studied the activity of acyloxyacyl hydrolase in neutrophils that had been isolated from the blood of 18 dairy cows around partu- rition. Between 10 and 26 d after parturition, the decreased approximately 20/100 below prepartum ac- tivity.