Immunomodulating dose of levamisole stimulates innate immune response and prevents intestinal damage in porcine rotavirus diarrhea: a restricted-randomized, single-blinded, and placebo-controlled clinical trial

A restricted-randomized, single-blinded, placebo-controlled clinical trial was conducted to examine whether immunomodulating dose of levamisole (LMS) can stimulate certain antiviral immune markers by measuring the concentrations of interferon- (IFN-), nitric oxide (NOx), and total immunoglobulin G (IgG); prevents the gut injury; and reduces fecal consistency and dehydration scores in rotavirus type A (RVA)-positive piglet diarrhea. The trial was executed between November 2015 and May 2016 in an institute owned experimental swine production farm. The naturally RVA-exposed diarrheic piglets were used in the study. The piglets born between November 2015 and May 2016, age group of 0 to 2weeks and confirmed for RVA-positive diarrhea, were randomized to receive supportive treatment (ST) or ST along with levamisole (LMS + ST) at immunomodulating dose. Simultaneously, six piglets were randomly selected from healthy population and kept as placebo control. The primary outcome was reduction of fecal consistency and dehydration scores (1) over the trial period. The secondary outcome was reduction of concentration of gut injury marker and stimulation of immunomodulatory function. The LMS + ST treatment progressively improved the total leukocyte, neutrophil count, IgG concentration (p<0.05), and reduced the intestinal fatty acid-binding protein 2 (IFABP-2) concentration in RV-positive diarrheic piglets than ST only. Although NOx and IFN- concentrations were enhanced initially on day 3, however, the values reduced significantly on day 5 in response to LMS + ST compared to ST. Interestingly, the scores of fecal consistency and dehydration of RVA-positive diarrheic piglets were dropped much earlier (on day 3) in response to LMS + ST than ST alone. The results indicate that LMS along with supportive treatment non-specifically modulated innate immunity and restored intestinal gut health, and thus, LMS may represent an additional therapeutic agent for management of RVA-inflicted piglet diarrhea.