Molecular detection of chlamydial agents in pinnipeds from the north coast of San Matias Gulf (Patagonia, Argentina)

ORIGLIA JAVIER; DANERI, GUSTAVO A.; TIZZANO MARCO ; SGUAZZA HERNAN ; HARRINGTON, ANA; VARELA, ESPERANZA A.; CADARIO MARIA ESTELA

Valdivia

Conferencia; V CONFERENCIA BIENAL WDA LATINOAMÉRICA; 2022

WDA LATINOAMÉRICA

Chlamydial agents have been described in a wide range of vertebrates. Despite this,few information is available on these bacteria in marine mammals. The aim of thisstudy was the detection and molecular characterization of Chlamydiaceae in pinni-peds that inhabit the marine littoral zone of Río Negro province (Argentina). BetweenDecember 2017 and March 2022, respiratory samples were obtained from 12 pinnipedspecimens (5 alive and 7 dead) from Punta Bermeja and Promontorio Belen rookerieslocated on the north coast of the San Matías Gulf. Two Mirounga leonina (SES) andthree Otaria byronia (SASL) individuals were anesthetized and nasal swabs were sub-sequently obtained. Additionally, nasal and/or tracheal swabs were taken from sevenSASL specimens found dead with a grade 2 carcass conservation status. All sampleswere stored in transport medium and refrigerated. After DNA extraction with a com-mercial kit, a Chlamydiaceae-specific qPCR (23S rRNA) was performed and positivesamples were rechecked with a Chlamydia psittaci-specific qPCR (ompA). An end-point PCR (ompA) was used to obtain products to be sequenced. From 16 samplesexamined (12 nasal swabs and 4 tracheal swabs) Chlamydiaceae was identified in 3nasal swabs (1 SES and 2 SASL) and in 1 tracheal swab with traces. All samples werenegative for detection of Chlamydia psittaci. It was possible to sequence one of thenasal samples which showed 92.8% identity with Chlamydia felis when analyzed withBLAST. This is the first report of Chlamydiaceae-DNA being found in SES and SASL.Taking into account this finding, we consider of great importance to enhance thistype of studies on the different populations of pinnipeds in Argentina and elsewhere.This will permit to determine whether or not these microorganisms are pathogenicand if they are typical of pinnipeds or they derive from anthropogenic impacts.Funds were partially provided by Zebra foundation.