形態・生理

[VII-20-05] Leukocytes function in goat milk after intrauterine infusion of lipopolysaccharide

*Jirapat Jaisue¹, Takahiro Nii¹, Naoki Suzuki¹, Naoki Isobe¹ (1. Hiroshima University)

A previous study found that intrauterine infusion of lipopolysaccharide (LPS) for 7 days can induce inflammation in the mammary gland, followed by its recovery, suggesting occurrence of endotoxin-tolerance (ET) in the mammary gland. The current study aimed to investigate the function of leukocytes in milk under ET condition. In the first experiment, to confirm whether LPS translocates from uterus to mammary gland, 100 μg LPS dissolved in 5 mL black ink was infused into uterus of goats every day for 5 days. The black particles were detected in blood and milk more than 2 h after the first infusion, also in the connective tissue of the mammary gland after 5 days. In the second experiment, goats were divided into 2 groups: with (IU) and without (CON) ET condition induced by intrauterine infusion of 100 μg of LPS in saline for 3 days. Then, LPS was infused into mammary gland in both groups to investigate the function of milk leukocytes under ET. Phagocytosis activity and CD11b expression of leukocytes in IU group were greater than those in CON group. These results suggest that ET enhances the function of leukocytes in milk.