Effect of enterocin M and durancin ED26E/7 supplementation on blood parameters, immune response and jejunal morphometry in rabbits.

Natural feed additives application in rabbit nutrition can help to control and prevent digestive disturbances and improve gut health and immunity around the critical weaning period. While probiotics are frequently used in rabbits, in vivo administration of bacteriocins is often limited. Therefore, the present study evaluates the effect of enterocin EntM, durancin EntED26E/7 and their combination on serum biochemistry, phagocytic activity and jejunal morphometry of rabbits. Eighty rabbits (aged 35 days, meat line M91, both sexes) were divided into experimental groups E (EntM; dose 50 µl/animal/day, activity 25,600 AU/ml), D (EntED26E/7; 50 µl/animal/day, 12,800 AU/ml), E + D (50 µl EntM + 50 µl EntED26E/7 /animal/day) and control group (C). Additives were administrated in drinking water for 21 days. Both enterocins positively influenced tested serum parameters, with emphasis on durancin EntED26E/7 administration, alone and/or in combination with EntM. Increased total proteins (E, D: p < 0.001), urea (D: p < 0.001), albumin (D: p < 0.05) and triglycerids (E, D, E+D: p < 0.001) were found. Hypocholesterolaemic effect of both additives was recorded (p < 0.001), with the lowest HDL concentration in E + D. The most of tested hepatic enzymes were positively influenced by enterocins combination (E + D; p < 0.001). The lowest AST was noted in group D (p < 0.001). Mineral profile was also improved (p < 0.001), with the highest values in D. Oxidative stress, was not evoked during enterocins application. Both additives showed a tendency to improve phagocytic activity (prolonged effect of EntED26D/7; D, E+D: p < 0.05) and jejunal morphometry parameters (increased villus cut surface; E, D, E+D; p < 0.001). Diet supplementation with EntM and mostly with EntED26E/7 can improve serum biochemistry, phagocytic activity and jejunal morphometry.