A study was conducted to evaluate the effects of 3 different plant extracts (PE) on diarrhea and intestinal morphology of weaned pigs experimentally infected with a pathogenic F-18 E. coli (toxins: LT, STb, and SLT-2; 1010 CFU/3 mL oral dose daily for 3 d). Weaned pigs (n = 64, 6.3 ± 0.2 kg BW, 21 d old) were used in a 2 x 4 factorial arrangement (with or without an E. coli challenge; 4 diets (a nursery basal diet (CON), 10 ppm capsicum oleoresin, garlic, or turmeric oleoresin)) and housed in disease containment chambers for 15 d (4 d before and 11 d after the first inoculation (d 0)). The growth performance was measured on d 0 to 5, 5 to 11, and 0 to 11. Diarrhea score (DS; 1, normal, to 5, watery diarrhea) was recorded for each pig daily. Frequency of diarrhea (FD) was the percentage of pig days with DS of 3 or higher. Feces were collected on d 0, 3, 5, 8, and 11 and plated on blood agar to calculate a ratio (RHT) of β-hemolytic coliforms to total coliforms by assessing the populations visually using a score (0, no bacterial growth, to 8, very heavy bacterial growth). On d 5 and d 11, half of the pigs were killed to collect jejunum, ileum, and colon to measure villi height (VH), crypt depth (CD), and their ratio (VH:CD).
In the challenged group, the PE treatments reduced (P < 0.05) average DS from d 0 to 2 (2.23 vs. 3.43) and from d 6 to 11 (1.50 vs. 3.51) and overall FD (20 vs. 40%), increased ileal VH on d 5 (316 vs. 263 μm), and tended (P ≤ 0.10) to increase jejunum VH (303 vs. 259 μm) and VH:CD (1.42 vs. 1.15) compared with the CON, but did not affect growth performance and RHT. Garlic enhanced VH:CD (1.60 vs. 1.18) compared with capsicum oleoresin. In the sham group, PE treatments improved (P < 0.05) ADG from d 0 to 5 (418 vs. 328 g/d) and reduced average DS from d 3 to 5 (1.49 vs. 2.06) and overall FD (6.7 vs. 20%) compared with the CON. The E. coli infection worst overall ADG, G:F and VH, and increased DS, FD, and RHT as expected.
In conclusion, all 3 PE tested reduced diarrhea and increased the villi height of the small intestine of pigs infected with E. coli.
Y Liu, M Song, TM Che, JA Soares, D Bravo, CW Maddox, JE Pettigrew. 2011. Effects of plant extracts on diarrhea and intestinal morphology of newly weaned pigs experimentally infected with a pathogenic E. coli. Journal of Animal Science, 89 (E-Suppl. 2): page 134.