Effect of natural microbiota treatment on the chicken microbiota, immune system and induction of vaccine responses

The microbial communities (microbiota) that colonise the gastrointestinal and respiratory systems can impact chicken health, and lead to changes in immune responses. Chickens are commonly raised without maternal contact and therefore are not exposed to a mature adult microbiota. To attempt to rectify this issue many farmers spray chicks with commercial probiotic mixtures of bacteria. One of the most common products used for this purpose is Aviguard. As Aviguard is delivered by spray onto chicks it is likely that their respiratory system is exposed to the product. This may impact their respiratory microbiota and the development of the respiratory immune system. In this study we assessed the effect of Aviguard treatment on the respiratory and gut microbiota (via 16S rRNA gene sequencing). Funded by a Houghton Trust small project grant (HT/SPRG/19/05). DNA was extracted using the Qiagen DNeasy PowerSoil Kit following the manufacturer's instructions, with 45 seconds of bead beating at 5 metres per second. i16S rRNA gene primers used: V4 read 1: TATGGTAATTGTGTGCCAGCMGCCGCGGTAA V4 read 2: AGTCAGTCAGCCGGACTACHVGGGTWTCTAAT V4 index: ATTAGAWACCCBDGTAGTCCGGCTGACTGACT