Weanling piglets often develop
respiratory diseases such as
pneumonia because they encounter substantial environmental stress. This study investigated an alternative herbal feed additive, Guizhi Li-Zhong Tang (GLZ), for preventing
pneumonia in weanling piglets. An in vitro experiment demonstrated that GLZ has high
antioxidant capacity and low cytotoxicity toward Kupffer cells. In addition, GLZ treatment can alleviate
lipopolysaccharide (LPS)-induced damage in Kupffer cells. A total of 94 4-week-old piglets were randomly divided into three groups, which received
sham treatment, 0.2%
Tilmicosin antibiotic (TAB) treatment, or 0.2% GLZ treatment. Piglets receiving the GLZ treatment had a higher survival rate and higher
immunoglobulin G levels but lower
allergy-related eosinophil levels and
cough incidence than did piglets receiving the
sham or 0.2% TAB treatments. Through immunohistochemistry and Western blot analysis, we discovered that piglets receiving the 0.2% GLZ treatment had significantly higher expression of
antioxidant-related SOD2 and lower expression of oxidative-stress-related 3-NT (p < 0.01),
inflammation-related TNF-α (p < 0.01) and NF-κB (p < 0.05), and apoptosis-related
caspase-3 (p < 0.01) in lung tissue than did piglets receiving the
sham or 0.2% TAB treatment. Therefore, GLZ treatment is promising as an alternative to
antibiotic medicine for weanling piglets because of its protective antioxidative, anti-inflammatory, and antiapoptotic effects in lung tissue.