Assessment of the ability of dietary yeast-fermented rapeseed meal to modulate inflammatory and oxidative stress in piglets after weaning

The ban on the use of antibiotics in feed (EC, 2006) has had a significant impact on the livestock sector, especially for pigs after weaning (Taranu et al., 2015). Consequently, it is necessary to find new sources of antimicrobial compounds, which has opened up many opportunities for animal nutrition research. The processing of plants (oilseeds, cereals, medicinal plants, etc.) for feed or food, or non-food products (e.g. oil, alcohol, kerosene, etc.) generates a wide range of by-products with significant ABSTRACT. The aim of the study was to investigate the potential of a diet containing rapeseed meal fermented by Saccharomyces cerevisiae as a new sustainable feed to reduce transient intestinal inflammation, diarrhoea and oxidative stress in piglets after weaning. In this study, 16 male post-weaning piglets, with an initial weight of 9.04 ± 0.19 kg, were randomly allocated to two dietary treatments: control and 10% fermented rapeseed meal (FRSM) – 8 pigs/treatment. The experiment lasted 21 days. At the end of the trial, the animals were slaughtered and samples of blood and segments of the jejunum, ileum and colon were collected for determination of plasma biochemical, inflammatory and oxidative stress parameters. Pig performance and diarrhoea incidence were also investigated. The results showed that the FRSM diet had no significant effect on piglet performance, weight and average daily weight gain, as well as plasma biochemical parameters. However, the number of piglets with diarrhoea was higher in the control group than in the group receiving the FRSM diet throughout the experimental period. Moreover, a decrease in TNF-α (P = 0.03) and IL-1ß (P < 0.05) cytokine levels was recorded in the colon and jejunum samples from the FRSM group. In addition, IL-8 and IL-6 concentrations were decreased (P = 0.0009 and P = 0.03, respectively) in the ileum of piglets fed FRSM, indicating the modulatory capacity of this feed in reducing weaning-associated intestinal inflammation. The FRSM diet also improved the antioxidant status and significantly reduced lipid peroxidation and thiobarbituric acid reactive substance levels in plasma (P = 0.022) and in the jejunum (P = 0.028) and colon (P = 0.003), suggesting the potential of fermented rapeseed meal to limit oxidative reactions. In conclusion, the present study showed that fermentation of rapeseed meal using S. cerevisiae enriched the nutrient composition and reduced the concentration of anti-nutrients (e.g. glucosinolates). Moreover, the addition of FRSM to diets of pigs after weaning improved their intestinal health status, indicating its beneficial effect. Received: 14 January 2022 Revised: 7 March 2022 Accepted: 5 April 2022