Study on the alleviative effect of Lactobacillus plantarum on Eimeria falciformis infection.

Coccidia of the genus Eimeria are specialized intracellular parasitic protozoa that cause severe coccidiosis when they infect their hosts. Animals infected with Eimeria develop clinical symptoms, such as anorexia, diarrhea, and hematochezia, which can even cause death. Although the current preferred regimen for the treatment of coccidiosis is antibiotics, this treatment strategy is limited by the ban on antibiotics and the growing problem of drug resistance. Therefore, the exploration of alternative methods for controlling coccidiosis has attracted much attention. Lactobacillus plantarum has been shown to have many beneficial effects. In this study, L. plantarum M2 was used as a research object to investigate the effect of L. plantarum on intestinal inflammation induced by infection with Eimeria falciformis in mice by detecting indicators, such as oocyst output, serum cytokines, and the intestinal microbiota. Compared with that in the infection group, the percent weight loss of the mice that were administered with L. plantarum M2 was significantly reduced (P < 0.05). Supplemented L. plantarum M2 and probiotics combined with diclazuril can reduce the total oocyst output significantly (P < 0.05, P < 0.001). L. plantarum M2 had outstanding performance in maintaining intestinal barrier function, and the levels of the mucin MUC1 and the tight junction protein E-cadherin were significantly elevated (P < 0.01, P < 0.05). Studies have shown that probiotic supplementation can alleviate adverse reactions after infection and significantly improve intestinal barrier function. In addition, probiotics combined with diclazuril could optimize the partial efficacy of diclazuril, which not only enhanced the effect of antibiotics but also alleviated their adverse effects. This study expands the application of probiotics, provides new ideas for alternative strategies for coccidia control, and suggests a basis for related research on lactobacilli antagonizing intracellular pathogen infection.IMPORTANCECoccidia of the genus Eimeria are specialized intracellular parasitic protozoa, and the current preferred regimen for the treatment of coccidiosis is antibiotics. However, due to antibiotic bans and drug resistance, the exploration of alternative methods for controlling coccidiosis has attracted much attention. In this work, we focused on Lactobacillus plantarum M2 and found that probiotic supplementation can alleviate adverse reactions after infection and improve intestinal barrier function. This study proposes the possibility of using lactic acid bacteria to control coccidiosis, and its potential mechanism needs further exploration.