Quantification and genetic profiling of DNA isolated from free-floating feces of the North Atlantic right whale (Eubalaena glacialis)

Fecal analysis from the highly endangered North Atlantic right whale provides valuable information about health and reproductive parameters of individual animals. Genetically profiling the feces facilitates this connection when the sample originator is unknown. Although genetic analysis of feces collected in terrestrial systems has become well established, genetic studies of cetacean DNA are rare. Here, the use of free-floating feces as a source of right whale DNA and the reliability of the genotypes produced are examined. On average, fecal extracts yielded 25 ng of DNA/mg dry weight, but less than 1% was right whale DNA. Although all samples were amplified using genus-specific mitochondrial control region primers, the quantity of right whale DNA present was over estimated when compared to amplifications using nuclear primers. No correlation was found between the quantity of right whale DNA recovered and the duration the sample sat in the water. Composite microsatellite profiles from multiple amplifications of 28 fecal samples of known origin were consistent with profiles of the same individuals obtained from skin biopsies, however, the rate of allelic dropout varied depending on the amount of right whale DNA added. A screening and genotyping protocol for reliable genetic profiling based on fecal DNA quantification is presented.