Methicillin-resistant Staphylococcus pseudintermedius among dogs in the description of novel SCCmec variants

S. pseudintermedius was isolated from 116/229 samples, eight of these were MRSP. Six MRSP CC45 isolates contained a pseudo-SCC element ΨSCCmec57395. Two isolates belonging to ST429 (CC761) and ST121 (CC121) contained novel variants of the SCCmec Type V(T) element. The elements were designated SCCmecV(T)SL/066, that carried additional transposon-related genes, and SCCmecV(T)SL/154 that carried a type III restriction-modification system, a type 7 ccr gene complex, and a cadA coding sequence. Thirty-seven percent of the dogs received antimicrobial treatment at the time of sampling of which four dogs were MRSP-positive. The proportion of MRSP among S. pseudintermedius is low compared to other countries, despite the fact that in Sri Lanka antimicrobials for treatment of dogs are available over the counter. Important is the finding of novel type V(T) SCCmec elements, which further underlines the high recombination frequency of SCC elements. The ΨSCCmec57395 was found in isolates of CC45, which is the only sequence type of MRSP known to contain this pseudo-cassette.