Effects of a tributyrin and monolaurin blend compared to high ZnO levels on growth performance, faecal microbial counts, intestinal histomorphometry and immunohistochemistry in weaned piglets: A field study in two pig herds

The objective of the present study was to evaluate the effects of a tributyrin and monolaurin blend compared to high ZnO levels in weaned piglets under field conditions. In Trial 1, piglets ( n = 168) were assigned to 1 of 2 treatments: 1) control (CON; diet supplemented with 3000 g ZnO/t of feed; n = 8 replicates); 2) tributyrin and monolaurin blend – Porcestin™ (PR; diet supplemented with basal level of ZnO at 150 g/t and with the tested blend at 5 kg/t of feed; n = 8 replicates). In Trial 2, piglets ( n = 244) were assigned to the same two treatments ( n = 10 replicates). The study duration was 4 (Trial 1) and 6 (Trial 2) weeks post-weaning. In both trials, growth performance was similar between treatments ( P > 0.05). In Trial 1, faecal counts of Lactobacillus spp. increased in pigs of PR group ( P < 0.05). In both trials, histomorphometrical analysis of jejunum and ileum samples showed a thicker intestinal mucosa in favor of the PR treatment ( P < 0.01), and Foxp3-positive regulatory T cells increased together with a concomitant decrease of MPO-positive granulocytes in jejunal mucosa of piglets from the PR treatment ( P < 0.01). Overall, supplementation of monolaurin and tributyrin blend compared to high ZnO levels resulted in similar growth performance. Moreover, beneficial effects on small intestinal morphometry and immune cells responses indicate its ability to attenuate inflammatory processes. Further research is necessary to optimize the use of tested product. • Effects of a monolaurin and tributyrin supplement were evaluated in weaned piglets. • Diets with monolaurin and tributyrin resulted in equivalent performance with ZnO. • Piglets fed the supplement had thicker intestinal mucosa in jejunum and ileum. • Compared to ZnO, monolaurin and tributyrin increased Lactobacillus spp. counts. • Foxp3+ cells increased in jejunal mucosa of treated piglets.