PSIV-B-24 - Dietary supplementation of botanicals changed blood profiles and intestinal morphology of weaned pigs experimentally infected with a pathogenic Escherichia coli

The objective of this study was to investigate the effects of dietary botanical supplementation on blood profiles and intestinal morphology of weaned piglets experimentally infected with a pathogenic F18 Escherichia coli (E. coli). Sixty weaned piglets (around 21 days old; 7.15 ± 0.97 kg) were individually housed and randomly allotted to one of five dietary treatments (n = 12): negative control (NC), positive control (PC), high dose of botanicals blend 1 (BB1, 100 mg/kg), and low or high dose of botanicals blend 2 (BB2, 50 mg/kg and 100 mg/kg). The experiment lasted 28 days: from day -7 to +21 relative to E. coli inoculation. All piglets except the NC group were orally inoculated with F18 E. coli (10 cfu per dose, 3 doses) for 3 consecutive days. Blood samples were collected on d 0, 5, 14, and 21 post-inoculation (PI) to perform complete blood count test. Intestinal segments were collected on d 5 and 21 PI for intestinal morphology analysis. Data were analyzed by ANOVA using PROC MIXED of SAS with a randomized complete block design. E. coli infection reduced (P < 0.05) neutrophils and lymphocytes, but increased (P < 0.05) monocytes on d 4 PI. Pigs supplemented with 100 mg/kg BB2 had less (P < 0.05) lymphocytes than pigs in PC on d 4 PI. Pigs fed with 50 mg/kg BB2 had lower (P < 0.05) lymphocytes and monocytes then pigs in PC on d 21 PI. Pigs supplemented with 100 mg/kg BB2 had the greatest (P < 0.05) duodenal villi width, jejunum villi height and area, and colon crypt depth then pigs in PC on d 5 PI. In conclusion, dietary supplementation of botanicals tended to affect systemic immunity and enhance intestinal morphology of weaned pigs infected with E. coli.