To explore the effects of maggot antimicrobial peptide treatment of Salmonella pullorum-infected chickens on the mRNA expression levels of TGF-β4 and TNF-α in small intestinal mucosa, the duodenum, jejunum and ileum mucosa were isolated 3, 5 and 7 days after induced AMP, non-induced AMP, antibiotics or maggot treatment and the TGF-β4 and TNF-α mRNA expression was evaluated by quantitative real-time PCR. We found that mRNA of TGF-β4 was highly expressed in the duodenum, jejunum, and ileum when Salmonella pullorum-infected chickens were treated with antibiotics, non-induced AMP, and AMP, respectively (P<0.001). Similarly, TNF-α mRNA was highly expressed in the duodenum and jejunum when Salmonella pullorum-infected chickens were treated with induced AMP and maggots, respectively (P<0.001), and the expression of TNF-α mRNA was higher in response to the use of induced AMP than antibiotics on day 5 after treatment (P<0.05). Therefore, maggot AMP functional efficiency, along with evaluation of TGF-β4 and TNF-α produced by small intestinal mucosa, may be useful for the prevention and treatment of Salmonella pullorum when developing new chicken feed additives.

Key words: Chickens, Intestinal mucosa, Maggots, Salmonella, TGF-β_4, TNF-α