Chinese Herbal Medicine Formula Guizhi Li-Zhong Tang as an Alternative to Antibiotic Feed Additives for Preventing Pneumonia in Piglets through Antioxidant, Anti-Inflammatory, and Antiapoptotic Protection.

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.

Alternative antibiotic feed additives alleviate pneumonia with inhibiting ACE-2 expression in the respiratory system of piglets.

Weaning piglets often suffer from pneumonia during growth, so in general, antibiotics are used by owners to make piglets grow smoothly. However, antibiotics may be accompanied by many side effects such as gastrointestinal discomfort and allergies. The aim of this study was to develop an alternative antibiotic herbal veterinary medicine for alleviating pneumonia in weanling piglets. As observed in the pig ranches, many weanling piglets suffer from the pneumonia and also show high expression of angiotensin-converting enzyme 2 (ACE-2) in their respiratory and intestinal tracts. ACE inhibitors have been reported that can decrease pneumonia risk through their main mechanism of action. Thus, we also try to find alternative antibiotic feed additives that can reduce expression of ACE-2 in piglets. We selected the Guizhi Li-Zhong Tang Extract Granules (GLZ) as a natural product for piglets. Then, we compared the serum immunoglobulin levels of piglets with sham, tilmicosin antibiotic (TAB), and GLZ treatments. Our results showed that piglets with GLZ treatment had significantly a higher expression of immunoglobulin A and immunoglobulin G but a lower expression of immunoglobulin E than those with sham and TAB treatments. In addition, piglets with GLZ treatment showed obviously low pneumonia incidence than those with sham and TAB treatments. Similarly, piglets with GLZ treatment showed significantly lower expressions of ACE-2 in their tracheal, bronchial, and lung tissues than those with sham and TAB treatments. GLZ seems to be an alternative ACE inhibitor that can decrease pneumonia risk through inhibiting ACE-2 expression and alleviating allergies in their respiratory systems. Thus, we suggest that GLZ can be an alternative antibiotic feed additive for weaning piglets.