Effect of dietary organic selenium on growth performance, gut health, and coccidiosis response in broiler chickens

Authors: WICKRAMASURIYA, SANIRU - US Department Of Agriculture (USDA); PARK, INKYUNG - US Department Of Agriculture (USDA); LEE, YOUNGSUB - US Department Of Agriculture (USDA); Lillehoj, Hyun

Submitted to: Animals
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/5/2023
Publication Date: 5/6/2023
Citation: Wickramasuriya, S.S., Park, I., Lee, Y., Lillehoj, H.S. 2023. Effect of dietary organic selenium on growth performance, gut health, and coccidiosis response in broiler chickens. Animals. https://doi.org/10.3390/ani13091560.
DOI: https://doi.org/10.3390/ani13091560

Interpretive Summary: Coccidiosis is caused by several distinct species of Eimeria parasites and costs the global poultry industry more than $ 14.5 billion in annual losses. The development of a novel antibiotic-alternative strategy to mitigate coccidiosis will have a significant impact on the poultry industry since the use of in-feed antibiotics at subtherapeutic levels has been restricted since 2014. In this study, ARS scientists explored the potentials of dietary selenium (Se) to mitigate the negative effects of coccidiosis in young broiler chickens, since Se has been used in poultry diets for a few decades because of its well-known benefits including growth performance improvement, enhancing reproduction, and immune function. Coccidiosis infection destroys intestinal integrity resulting in poor nutrient absorption and hinders optimal growth performance via gut epithelial damage. To further understand the impact and interactions of dietary Se and the Eimeria infection on broiler gut health, we assessed the Se effects on the tight junction and mucin gene expression in the duodenum and jejunum mucosa. The tight junction is an integral part of the intercellular junctional complex of intestinal epithelial cells which plays a vital role in the gut health of the host animals. Our study showed that organic selenized yeast-fed chickens showed higher gut integrity and improved gut health. Furthermore, selenized yeast showed higher Se retention in serum and breast meat. Therefore, dietary Se supplementation in young broiler chickens will enhance gut health while promoting growth performance. Specifically, the addition of organic selenized yeast improved growth performance and enhanced Se accumulation in the tissue, and therefore, organic Se supplementation is beneficial to produce Se-enriched organic broiler chickens. These findings will help poultry feed companies to develop novel antibiotic alternative feed additives to promote poultry gut health and reduce the economic costs due to coccidiosis.

Technical Abstract: The present study was conducted to investigate the effect of dietary organic selenium (Se) supplementation on growth performance, gut health, and selenium accumulation in coccidiosis-infected broiler chickens. A total of 252 one-day-old Ross broilers were randomly allocated into one of six treatments in a 2 × 3 factorial arrangement with respective Eimeria challenges (non-infection and infection) and the three different Se diets. Dietary treatments were as follows: (1) Se un-supplemented control (CON), (2) Inorganic Se treatment (SS; 0.3 mg/kg as sodium selenite), and (3) Organic Se treatment (SY; 0.3 mg/kg as Selenized yeast, Sel-Plex®). Six replicate cages (seven chickens each) were allocated per treatment. Chickens in the respective Eimeria infection groups were infected with E. acervulina, E. tenella, and E. maxima oocysts mixture (15,000 oocysts/chicken) on day 16. Growth performance was measured on days 16, 22, and 24. On day 22, intestinal samples were collected from randomly selected chickens to evaluate gut lesion score, antioxidant enzymes, and tight junction gene expressions. Blood, breast, and liver samples were collected to analyze the Se accumulation on day 24. Dietary SY supplementation improved (P < 0.05) the growth performance of the chickens regardless of the Eimeria challenge. Moreover, independent of Eimeria infection, Se supplementation elevated (P < 0.05) the HMOX-1 expression in jejunal mucosa at 6-day post-infection (dpi). Duodenal JAM-2 expression and jejunal OCLN were elevated (P < 0.05) with dietary SY supplementation at 6 dpi. Among Se sources, broiler chickens fed with the SY diet showed a higher (P < 0.05) Se accumulation in breast muscle and serum on 8 dpi. These results confirmed the beneficial effect of dietary Se and the efficiency of organic Se compared with inorganic Se for growth improvement and muscle Se enrichment of broiler chickens regardless of coccidiosis infections.