The Administration Effect of Lactic Acid Bacteria Reducing Environmental Alkyl and Fatty Acid Hydroperoxides on Piglets in the Absence of Antimicrobial Agents and in the Presence of Iron

A lactic acid bacterium, Lactiplantibacillus plantarum P1-2 ( Lp P1-2), can reduce environmental fatty acid hydroperoxides. The administration of Lp P1-2 to oxygen-sensitive short-lived nematode mutants and iron-overloaded rats reduced the oxidative stress-related index. Since young piglets have a weak defense system against oxidative stress and are vulnerable to environmental stress, antimicrobial agents have been administered in the rearing. Based on these results, we investigated the effect of Lp P1-2 administration to prepartum sows and infant piglets until weaning without antimicrobial agents on the growth of young piglets. The group including both sows and piglets that were administrated with lactic acid bacteria containing Lp P1-2 (LAB Lp ) until the end of lactation showed the growth-promoting effect of piglet from lactation to early regular rearing, and even in late regular rearing. Blood biochemical markers were in the normal ranges in both LAB Lp -administrated and non-administrated groups, but various disease-related markers tended to decrease in the administrated group. To investigate the effects of LAB Lp administration on postpartum piglets, the piglets born from prenatally LAB Lp -administrated sows were divided into two groups and then administrated with or without LAB Lp . The piglets in the LAB Lp -administrated group tended to grow very slightly higher than those in the non-administrated group from lactation to early regular rearing. After that, the growth in both groups was almost the same. These results suggest that LAB Lp administration to prepartum sows is essential for the growth-promoting effect. The postnatal LAB Lp -administrated piglets showed a lower serum lipid peroxidation index than the non-administrated piglets, and had higher numbers of lactic acid bacteria and bifidobacteria in feces at the end of LAB Lp treatment. In fattening performances, the LAB Lp -administrated group showed a significant improvement in meat quality. We also discuss the growth and physiological effects by Lp P1-2 administration with iron on piglets because iron administration is another important issue in piglet farming. ### Competing Interest Statement The authors have declared no competing interest.