Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/20/2014
Publication Date: 5/1/2014
Publication URL: http://handle.nal.usda.gov/10113/61050
Citation: Lee, S.H., Lillehoj, H.S., Jeong, M., Xu, S., Kim, J.B., Park, H.J., Lillehoj, E.P., Bravo, D. 2014. Effect of in ovo injection with selenium on immune and antioxidant responses during experimental necrotic enteritis in broiler chickens. Poultry Science. 93(5):1113-21. doi: 10.3382/ps.2013-03770. Interpretive Summary: Selenium (Se) is a micronutrient with many proven beneficial effects in humans. As a dietary supplement, Se reduces certain harmful effects induced by bacteria and enhances host immunity against pathogens. In this report, ARS scientists used this information to utilize Se as a dietary supplement to enhance avian immunity against a gut bacterium, Clostridium perfringens (C. perfringens). It is well known that early infection with Clostridium bacteria in young poultry causes negative effects on their growth and delays proper functioning of the immune system in their gut. This study showed that administration of Se injected into the egg during embryonic development (in ovo) reduced the level of anti-oxidant proteins induced by Clostridium infection and increased serum proteins against major toxins of C. perfringens. Further, the beneficial effects of giving Se to young chickens suggest that we can improve productivity of commercial poultry by providing critical nutrients that can boost host immunity. This information will help nutrition companies to produce more effective diets for growing poultry.
Technical Abstract: Selenium (Se) is an essential component of several major metabolic pathways in the antioxidant enzymes activity and modulating immune system. This study was conducted to investigate the effects of in ovo injection of selenium (Se) on modulating the immune system and antioxidant responses in chickens with experimental necrotic enteritis (NE). Broiler eggs were injected at 18 days of embryo age with either 100 µl of PBS alone or sodium selenite (Na2SeO3) in PBS, providing 0 (SS0 group), 10 (SS10 group), or 20 (SS20 group) µg Se/egg. At 14 days post-hatch, PBS-treated and uninfected chickens were kept as the control group while the remaining chickens were orally infected with 1.0 × 104 sporulated oocysts of Eimeria maxima (SS0, SS10, SS20). At 18 days post-hatch, E. maxima-infected chickens were orally infected with 1.0 x 109 colony forming units of Clostridium perfringens. Se-treated and co-infected birds in both the SS10 and SS20 groups had increased body weights, fewer intestinal lesions, reduced oocyst production, diminished serum malondialdehyde, catalase, and superoxide dismutase levels, and decreased intestinal glutathione peroxidase 7 mRNA levels compared with untreated and co-infected controls (SS0). SS10 and SS20 chickens also had higher levels of transcripts for interleukin (IL)-1ß, IL-6, IL-8, and inducible nitric oxide synthase expression in the intestine and increased antibody levels to C. perfringens a-toxin and NetB toxin in serum compared with the SS0 group. No significant differences were found in tissue Se levels among any of the treatment groups. These collective results suggest that injection of Se into the yolk of incubating eggs may be beneficial for enhancing immune and antioxidant responses to necrotic enteritis in broiler chickens.