183 Evaluation of phytogenic formulations on intestinal health and the performance of nursery pigs challenged with F18+Escherichia coli.

Abstract

Abstract The objective of this study was to evaluate phytogenic formulations on intestinal health and growth performance of nursery pigs challenged with F18+Escherichia coli. Weaned pigs [n = 40; initial body weight (BW) = 6.4 ± 0.1 kg] at 21 d of age were individually housed and assigned to 4 dietary treatments in a randomized complete block design, with initial BW and sex as blocking factors. Basal diets were formulated following NRC (2012) and fed to pigs for 28 d in 3 phases (P1:11 d, P2:10 d and P3:7 d). Treatments were NC: basal diet, non-challenge; PC: basal diet, challenged with F18+E. coli; AV1: basal diet supplemented with 1% phytobiotic containing herbal extracts and essential oils in powder form, challenged with F18+E. coli; AV2: basal diet + 1% phytobiotic containing herbal extracts and essential oils in liquid form, challenged with F18+E. coli. Growth performance and fecal score (FS) were measured weekly. On d 7, the challenged groups were orally inoculated with F18+E. coli (2.0 × 1010), whereas unchallenged pigs received a sterile saline solution. On d 28, all pigs were euthanized to collect jejunal samples to evaluate inflammatory status, oxidative stress, and diversity and relative abundance of mucosa-associated microbiota. Data were analyzed using the MIXED procedure on SAS 9.4. During the post-challenge period, PC decrease (P < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) when compared with NC. The PC increased (P < 0.05) FS during d 7 to 11 when compared with NC, whereas AV1 and AV2 decreased (P < 0.05) FS during d 7 to 11 when compared with PC. The AV1 decreased (P < 0.05) Chao1 and Shannon indexes when compared with PC. The PC increased (P < 0.05) the relative abundance of Prevotellaceae, Lachnospiraceae, and Ruminococcaceae compared with NC. The AV1 reduced (P < 0.05) the relative abundance of Veillonellaceae, Prevotellaceae, Lachnospiraceae and tended to reduce (P = 0.062) the relative abundance of Ruminococcaceae when compared with PC. The AV2 tended to reduce the relative abundance of Streptococcaceae (P = 0.073) and Ruminococcaceae (P = 0.074) when compared with PC. The PC increased (P < 0.05) occludin and tended to increase (P = 0.096) TLR4 when compared with NC. The AV1 tended to increase (P = 0.053) protein carbonyl when compared with PC. In conclusion, F18+E. coli challenge increased FS, disrupted the mucosa-associated microbiota, increased TLR4 expression, consequently reduced growth performance of pigs. The AV1 showed promise in reducing oxidative stress during F18+E. coli challenge, seen through decreased protein carbonyl levels possibly due to alterations on mucosa-associated microbiota, although without affecting growth performance. The AV2 had a moderate impact on reducing FS and altering mucosa-associated microbiota, without effect on growth performance.