Effect of Baicalin on Bacterial Secondary Infection and Inflammation Caused by H9N2 AIV Infection in Chickens

Abstract

H9N2 subtype avian influenza virus (H9N2 AIV) is a low pathogenic virus that is widely prevalent all over the world. H9N2 AIV causes immunosuppression in the host and often leads to high rates of mortality due to secondary infection with Escherichia. Due to the drug resistance of bacteria, many antibiotics are not effective in the treatment of secondary bacterial infection. Therefore, the purpose of this study is to find effective nonantibiotic drugs for the treatment of H9N2 AIV infection-induced secondary bacterial infection and inflammation. This study proves, for the first time, that baicalin, a Chinese herbal medicine, can regulate Lactobacillus to replace Escherichia induced by H9N2 AIV, so as to resolve the intestinal flora disorder. In addition, baicalin can effectively prevent intestinal bacterial translocation of SPF chickens’ post-H9N2 AIV infection, thus inhibiting secondary bacterial infection. Furthermore, baicalin can effectively treat H9N2 AIV-induced inflammation by inhibiting intestinal structural damage, inhibiting damage to ileal mucus layer construction and tight junctions, improving antioxidant capacity, affecting blood biochemical indexes, and inhibiting the production of inflammatory cytokines. Taken together, these results provide a new theoretical basis for clinical prevention and control of H9N2 AIV infection-induced secondary bacterial infection and inflammation.

The Effect of the Antimicrobial Peptide Plectasin on the Growth Performance, Intestinal Health, and Immune Function of Yellow-Feathered Chickens

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Serine Metabolism Tunes Immune Responses To Promote Oreochromis niloticus Survival upon Edwardsiella tarda Infection

“…Bacterial infection is still a risk factor for human health and poultry, taking large numbers of lives per year and causing huge economic loss ( 30 ). Due to widespread antibiotic-resistant bacteria, antibiotics are used with caution, and a backup strategy to deal with the infection is urgently needed.…”

The Use of Chinese Skullcap (Scutellaria baicalensis) and Its Extracts for Sustainable Animal Production

“…Baicalin can resolve intestinal dysbacteriosis caused by H9N2 subtype avian influenza infection by modulating lactic acid bacteria, thus preventing the high mortality caused by the secondary infection of Escherichia. Baicalin had beneficial effects for clinical prevention and control of H9N2 Subtype Avian infection and secondary bacterial infections and inflammation by inhibiting the loss of intestinal structure and improving antioxidant capacity, affecting blood biochemical indexes, and inhibiting the production of inflammatory factors [ 123 ]. Baicalin effectively treats polyserositis caused by Glaesserella parasitis infection by alleviating the downregulation of mRNA for tight junctions, preventing the abnormalities, and maintaining the integrity of tight junctions, and is a potential natural medicine for the prevention and treatment of G. parasitis [ 124 ].…”