Improving accuracy of DNA diet estimates using food tissue control materials and an evaluation of proxies for digestion bias.

摘要: Ecologists are increasingly interested in quantifying consumer diets based on food DNA dietary samples and high-throughput sequencing of marker genes. It is tempting to assume that sequence proportions recovered from diet representative consumer's proportions, despite the fact captive feeding studies do not support assumption. Here, we examine idea control materials known composition along with order correct for technical biases introduced during amplicon biological such as variable gene copy number. Using Ion Torrent PGM(©) , sequenced prey amplified scats harbour seals (Phoca vitulina) fed a constant including three fish species proportions. Alongside, tissue mix matching seals' generate correction factors (TCFs). TCFs improved estimates (based proportions) all reduced average estimate error 28 ± 15% (uncorrected) 14 9% (TCF-corrected). The experimental design also allowed us infer magnitude prey-specific digestion calculate (DCFs). DCFs were compared possible proxies differential (e.g. protein%, lipid%) revealing strong relationship between percent lipid prey, suggesting corrections content would produce accurate this study system. These findings demonstrate value parallel mixtures offer new directions future research quantitative analysis.