The Effects of Grounded Herbs on the Intestinal Villus Height and Shedding of F18-positive Escherichia coli in Weaned Pigs

Abstract

Antibiotics have been widely used to control and treat infections caused by Escherichia coli (E. coli) in weaned pigs. The bacteria resistance to antibiotics can occur naturally; however, the misuse of antibiotics can accelerate this resistance. New antibiotics are developed very slowly, and only two new classes of antibiotics have been developed in the past 40 years. This makes herbal medicine a promising method for fighting against antibiotic-resistant bacteria. In the current study, 25 male crossbred (Duroc x Landrace x Large white) weaned piglets with an average weight of 6-8 kg were examined for 24 days. The pigs were randomly assigned to five groups in a completely randomized design with five replicates (1 pig/pen). All treatments included 20% crude protein corn-soybean as the basal diet. The negative control group received no supplementation, while pigs in the second experimental group received a basal diet supplemented with 150 ppm colistin sulfate. Basal diet and herbal mixture (Andrographis paniculata, Zingiber cassumunar, and Garcinia mangostana) were fed to three other experimental groups at 500, 1000, and 2000 ppm. The F18-positive, colistin-resistant E. coli were orally inoculated to all pigs for 9 days. The antibacterial and anti-diarrheal effects of this diet and its effect on the inoculated pigs’ intestinal villi were evaluated. The results indicated that supplementation of this herbal mixture at levels of 500, 1000, and 2000 ppm had antibacterial effects, with no significant difference between doses. However, the positive effects of this herbal mixture on intestinal villi height and diarrhea were found only in pigs that received 1000 and 2000 ppm of the herbal mixture. From a practical point of view, supplementation of this herbal mixture at 500 and 1000 ppm could be applied for prophylaxis during the weaning period, whereas 2000 ppm of the herbal mixture could be used for the treatment of postweaning E. coli diarrhea.