Short-term effect of supplemental yeast extract without or with feed enzymes on growth performance, immune status and gut structure of weaned pigs challenged withEscherichia colilipopolysaccharide.
BACKGROUND
This study investigated the response of piglets receiving a yeast extract without or with a multi-enzyme mixture compared with an antimicrobial growth promoter (AGP) on performance, immune status and gut structure after anE. colilipopolysaccharide (LPS) challenge. Thirty-six pigs were allotted to six treatments including: a non-challenged control (NCC); LPS-challenged control (CC); CC + AGP; CC + yeast extract; CC + enzymes; and CC + enzymes + yeast extract. On d 7, pigs were bled and thereafter injected with LPS or sterile saline. Blood samples were collected at 6, 48, and 96 h post-challenge. After 96 h post-challenge, pigs were euthanized to obtain duodenal, jejunal and ileal samples.


RESULTS
Overall (d 1 to 11), compared with CC pigs, AGP attenuated the LPS-induced reduction in ADG (P= 0.004), ADFI (P= 0.03) and gain/feed ratio (P= 0.01). At 6 h post-challenge, AGP pigs had lower plasma urea N (PUN;P= 0.02) and serum TNF- α concentration (P= 0.07), and higher platelet count (P= 0.04) and serum IL-10 concentration (P= 0.02) than CC pigs. At 48 h post-challenge, AGP pigs had lower PUN (P= 0.02) than CC pigs, whereas enzymes + yeast extract interacted non-additively (P= 0.001) to reduce PUN. At 96 h post-challenge, AGP pigs had lower PUN (P= 0.02) and higher duodenal (P= 0.03), jejunal (P= 0.01) and ileal (P= 0.07) villus height than CC pigs. In addition, enzymes + yeast extract interacted additively and non-additively to reduce ileal IFN-γ (P< 0.0001) and IL-10 (P= 0.012) expression, respectively. Generally, no differences (P> 0.10) were observed between AGP and enzymes + yeast extract pigs on other measured parameters except for the downregulation of ileal IFN-γ (P< 0.0001) and TNF-α (P= 0.003) in enzymes + yeast extract pigs at 96 h post-challenge.


CONCLUSIONS
The LPS challenged piglets receiving enzymes + yeast extract showed beneficial responses in gut structure and immunity commensurate with those receiving antibiotics, though the latter had better overall growth performance.
Department of Animal Science, University of Manitoba, 201-12 Dafoe Road, Winnipeg, MB R3T 2N2 Canada.
Samuel M
SM
Waititu
Department of Animal Science, University of Manitoba, 201-12 Dafoe Road, Winnipeg, MB R3T 2N2 Canada.
Fugui
F
Yin
Canadian Bio-systems Inc., Calgary, AB T2C 0J7 Canada.
Rob
R
Patterson
Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 Canada.
Juan C
JC
Rodriguez-Lecompte
Department of Animal Science, University of Manitoba, 201-12 Dafoe Road, Winnipeg, MB R3T 2N2 Canada.
Charles M
CM
Nyachoti
Antimicrobial growth promoter; Feed enzymes; Growth performance; Immunity; Nucleotides; Piglets