Measuring the impact of dietary supplementation with citrus or cucumber extract on chicken gut microbiota using 16s rRNA gene sequencing

This study investigated the effects of dietary supplements, citrus (CTS) and cucumber (CMB), on the jejunum and cecum microbiota of 14- and 28-days old broiler chickens to evaluate their impact on the gut health and assess their role as alternatives to antibiotic growth promoters (ABGPs). 16SrRNA gene sequencing revealed the overall bacterial microbiota composition was significantly affected by the gut site (p?<?0.001) but not by either of the dietary supplements, CTS and CMB, at both 14 and 28 days of age. However, as a result of Linear discriminant analysis (LDA) effect size (LEfSE), CTS dietary supplements significantly increased the counts of Lactobacillus (p?<?0.01) and decreased the counts of Enterococcus (p?<?0.01) and Clostridium (p?<?0.05) in the jejunum, whereas the counts of Blautia were increased (p?<?0.01) and Enterococcus were decreased (p?<?0.05) in the cecum at both ages. Only minor CMB effects were identified in the cecum and non in the jejunum. The use of CTS dietary supplements has been shown to be associated to the reduction of potentially pathogenic bacteria (Enterococcus and Clostridium) and to the growth of beneficial bacteria (Lactobacillus and Blautia) which are known to have positive effects on chicken health in terms of nutrients absorption, stimulation and production of short chain fatty acids (SCFAs). Therefore, this study suggests that the use of a CTS supplemented diet could promote gut health while no clear advantages have been identified with the use of CMB as a dietary supplement.