Effects of glucose oxidase on growth performance, clinical symptoms, serum parameters, and intestinal health in piglets challenged by enterotoxigenic Escherichia coli

Abstract

Glucose oxidase (GOD) could benefit intestinal health and growth performance in animals. However, it is unknown whether GOD can protect piglets against bacterial challenge. This study aimed to evaluate the protective effects of GOD on growth performance, clinical symptoms, serum parameters, and intestinal health in piglets challenged by enterotoxigenic Escherichia coli (ETEC). A total of 44 male weaned piglets around 38 days old were divided into four groups (11 replicates/group): negative control (NC), positive control (PC), CS group (PC piglets +40 g/t colistin sulfate), and GOD group (PC piglets +200 g/t GOD). All piglets except those in NC were challenged with ETEC (E. coli K88) on the 11th day of the experiment. Parameter analysis was performed on the 21st day of the experiment. The results showed that the ETEC challenge elevated (p < 0.05) the rectal temperature and fecal score of piglets at certain time-points post-challenge, reduced (p < 0.05) serum glucose and IgG levels but increased (p < 0.05) serum alanine aminotransferase activity, as well as caused (p < 0.05) intestinal morphology impairment and inflammation. Supplemental GOD could replace CS to reverse (p < 0.05) the above changes and tended to increase (p = 0.099) average daily gain during the ETEC challenge. Besides, GOD addition reversed ETEC-induced losses (p < 0.05) in several beneficial bacteria (e.g., Lactobacillus salivarius) along with increases (p < 0.05) in certain harmful bacteria (e.g., Enterobacteriaceae and Escherichia/Shigella). Functional prediction of gut microbiota revealed that ETEC-induced upregulations (p < 0.05) of certain pathogenicity-related pathways (e.g., bacterial invasion of epithelial cells and shigellosis) were blocked by GOD addition, which also normalized the observed downregulations (p < 0.05) of bacterial pathways related to the metabolism of sugars, functional amino acids, nucleobases, and bile acids in challenged piglets. Collectively, GOD could be used as a potential antibiotic alternative to improve growth and serum parameters, as well as attenuate clinical symptoms and intestinal disruption in ETEC-challenged piglets, which could be associated with its ability to mitigate gut microbiota dysbiosis. Our findings provided evidence for the usage of GOD as an approach to restrict ETEC infection in pigs.

The combination of macleaya extract and glucose oxidase improves the growth performance, antioxidant capacity, immune function and cecal microbiota of piglets

“…Glucose oxidase (GOD) is an aerobic dehydrogenase that originates from the fermentation of specific fungal strains, including Aspergillus and Penicillium (12). This enzyme is capable of oxidizing β-D-glucose into gluconic acid, while also producing hydrogen peroxide (HP) through the consumption of oxygen (13). HP can inhibit the growth of harmful gut bacteria and prevent bacterial invasion (14).…”

“…In addition, dietary supplementation of 3,000 U/kg GOD can increase the total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activity in the jejunum of piglets (19). Research shown that 200 mg/kg glucose oxidase reduced the ETEC induced decrease of IgG content and the abundance of Lactobacillaceae and Lactobacillus salivarius in the intestine (13).…”