Evaluation of antimicrobial substances used for most common diagnoses in New World Camelids at the University Clinic for Ruminants, University of Veterinary Medicine, Vienna

Even with the rise of popularity of NWCs in the world and in Austria there are to our knowledge no antibiotic drugs on the market officially registered for NWCs. Veterinarians need to adapt and deal with these new patients as best as they can, using the existing drugs available for other species, including antimicrobial substances. With the ever rising threat of AMR, guidelines for using antimicrobial drugs need to be respected while combating diseases of NWCs. This retrospective study examined the most commonly observed diagnoses of 341 NWCs that received treatment at the University Clinic for Ruminants in the years between 2005 and 2019 and what antimicrobial drugs were used to treat them, while abiding to the published rules of correct conduct of antimicrobial usage. Most commonly observed diagnoses that needed antimicrobial treatment were diseases of the GI tract, followed by diseases of CNS, skin and various infections. Another commonly observed problems were diseases of the circulatory system and urinary tract. Most common antimicrobial drug used in the first years of this study was a combined substance of benzylpenicillin and dihydrostreptomycin. It was later replaced by aminopenicillins (no beta lactamase) and narrow spectrum penicillins, followed by aminopenicillins with beta lactamase inhibitors. Their usage responds to the published guidelines on using antimicrobial substances in veterinary medicine in Austria in 2018 and those already published by colleagues in Germany in 2015. These findings comply with EMA categorisation of antibiotic classes as these substances fall under category D (prudent use). Cephalosporins were mostly used in cases of dental disease and in orthopaedic patients. Their usage slowly declined after the published guidelines as they are registered in restricted group and should be only used where no other drugs are available and after antimicrobial susceptibility test. There were several studies and articles published regarding NWCs and their health since NWCs first became popular, but the dosages published still serve only as guidelines and most of them are taken from those used for cattle or small ruminants. Further research in health issues and treatment is still needed so that veterinarians can feel confident treating these rising numbers of new type of patients.