Effect of Panax ginseng on cytokine expression in bovine mammary glands at drying off

Biological response modifiers (BRM) are agents that modify the host's response to pathogens with resultant beneficial prophylactic or therapeutic effects. The objectives of this study were to describe the immunomodulatory effects of Panax ginseng (GS) on bovine mammary glands at the end of lactation. Eight mammary quarters from six nonpregnant cows in late lactation were infused with 10 mL of BRM (3 mg/mL), six quarters were treated with placebo (vehicle alone) and six quarters were maintained as uninoculated controls. Milk samples were collected at different time points for detection of specific cytokines mRNA by RT-PCR and Western blotting assay. A significant increase of IL-1α, IL-1β and TNF-α mRNA expression was observed in BRM-treated compared with placebo-treated quarters at 48 h post-treatment (pt) (P < 0.05). A 17 kDa TNF-α band expressed a sharp elevation at 24 h and reduction in its level at 48 h pt in BRM-treated quarters. Differences in this cytokine level between 24 and 48 h pt times were significant (P < 0.05). GS extract inoculation at drying off was associated with somatic cell counts increase, cytokines mRNA transcription and the presence of TNF-α in milk and can therefore exert immunomodulating effects in bovine mammary gland at drying off.