Location: Animal Biosciences & Biotechnology Laboratory
Title: Recombinant Bacillus subtilis carrying NK-lysin gene as an effective mucosal delivery strategy to prevent against avian coccidiosisAuthor
WICKRAMASURIYA, SAMIRU - US Department Of Agriculture (USDA) | |
PARK, INKYUNG - US Department Of Agriculture (USDA) | |
VAN OOSTERWIJK, JOLIEKE - Us Biologics | |
PRZYBYAZEWKI, CHRIS - Us Biologics | |
Gay, Cyril | |
Lillehoj, Hyun |
Submitted to: American Association of Avian Pathologists
Publication Type: Abstract Only Publication Acceptance Date: 1/8/2021 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: The chicken NK-lysin peptide 2 (cNK-2) is a natural lytic peptide with direct cytotoxicity against apicomplexan parasites such as Eimeria. Developing an effective oral delivery strategy to express cNK-2 in the intestine where Eimeria parasites interact with the host’s gut epithelial cells will reduce the fecundity of parasites and gut damage. Furthermore, cNK-2 modulates gut immune responses to decrease local inflammation elicited by parasite invasion of host cells. Therefore, we developed a stable strain of Bacillus subtilis that carries chicken NK2 peptide (B. subtilis-cNK2) to determine its effectiveness as an oral carrier of NK lysin peptide to the gut and to investigate its effect against coccidiosis infection in commercial broiler chickens. Chickens were allocated into four treatment groups in a completely randomized design: 1) negative control (NC, unchallenged), 2) positive control (PC: challenged without B. subtilis), 3) B. subtilis with empty vector (BSEV), and 4) B. subtilis-cNK2 (BSNK). All birds were challenged with 10,000 sporulated E. acervulina oocysts through oral gavage except the NC group. Chickens given BSEV or BSNK were orally gavaged on day 14, 15 and 16 (1×1010 cfu/mL) followed by oral challenge infection with E. acervulina. Infected chickens treated with BSNK showed improved (p<0.05) growth performance, gut integrity, and lower (p<0.05) oocysts shedding compared to infected and untreated controls. Taken together, this is the first demonstration to show dietary B. subtilis probiotics carrying chicken NK2 peptide can be an effective alternative to antibiotics strategy to reduce harmful effects of avian coccidiosis. |