Understanding the zoonotic pathogen, Coxiella burnetii in Australian fur seal breeding colonies through environmental DNA and genotyping

Context Coxiella burnetii is suspected as a novel pathogen contributing to decreased pup production in Australian fur seals (Arctocephalus pusillus doriferus). It has recently been described from single breeding colony Bass Strait, previously associated with two decreasing populations of northern hemisphere pinnipeds and known reproductive pathogen. Data around its disease ecology marine mammals are sparse.Aims To determine whether environmental DNA (eDNA) can be used survey for C. seal colonies. the same genotype terrestrial burnetii.Methods Soil samples were collected Kanowna Island Seal Rocks. Placental Island. was evaluated eDNA using quantitative polymerase chain reaction (qPCR) com1 gene. com1, htpAB IS1111 markers. Multiple-locus variable number tandem repeats analysis three microsatellite loci (ms-24, ms-28 ms-33) relatedness genotypes.Key results varied between pre-and post-pupping at When targeting gene, prevalence Rocks 59.6% 90%, respectively. PCR inhibition low 1.9%. There very poor, sporadic absent amplification placental samples. The qPCRs had an overall across 39.2% 56.7% In 90.1% (n=11), locus amplified. Neither ms-24 nor ms-33 amplified.Conclusions effective tool colonies period burnetii. appears much higher than colony. that this not but rather closely related genotypes detected hemisphere.Implications This research significantly expands our ability other mammals. highlights knowledge gaps understanding phylogeny