The aim of this study was continuous monitoring of the presence of mcr-1 to mcr-5 genes in Enterobacterales isolated from cattle, pigs, and domestic poultry at intensive breeding facilities in Northern Vojvodina, Serbia, from 1 January 1 to 1 October 2020. Out of 2167 examined samples, mcr-1 was observed in five E. coli isolates originating from healthy turkeys. Four isolates belonged to the phylogenetic group B1, and one isolate to the phylogenetic group A. Detected E. coli serogenotypes (somatic O and flagellar H antigens) were O8:H25 and O29:H25. Core-genome multi-locus sequence typing (cgMLST) revealed three ST58 isolates clustering together in Clonal Complex (CC) 155 and two singletons of ST641-CC86 and ST410-CC23, respectively. Clonotyping revealed CH4-32 (n = 3), CH6-53 (n = 1) and CH4-24 (n = 1). In all isolates, the mcr-1 gene was located on a large IncX4 replicon type plasmid. Eight virulence-associated genes (VAGs) typical of avian pathogenic E. coli (APEC) (fyuA, fimH, hlyF, iss, ompT, sitA, traT, iroN) were detected in four isolates. These isolates were investigated for susceptibility to four biocides and revealed MIC values of 0.125% for glutardialdehyde, of 0.00003–0.00006% for chlorohexidine, of 4–6% for isopropanol and of 0.001–0.002% for benzalkonium chloride. All obtained MIC values of the tested biocides were comparable to the reference strain, with no indication of possible resistance. This is the first report of mcr-1.1-carrying E. coli from Serbia. Although only samples from turkeys were mcr-positive in this study, continuous monitoring of livestock samples is advised to prevent a spill-over from animals to humans.

Case Report Mac Vet Rev 2016; 39 (1): 129-133 This paper describes the first documented case of cattle grub (hypodermosis) in Northern Serbia (Vojvodina). Subcutaneous warbles were determined in a si x year old Simmental cow, at nine places along the spine. After the extirpation of larvae, based on the morphological characterisation, larvae of the third stage of Hypoderma bovis were diagnosed. The cow was administered therapeutic treatment, which had a favorable outcome, with no signs of recurrence. To the authors' best knowledge, the case described in this paper is the first documented case of hypodermosis in cattle in Northern Serbia (Vojvodina). As the climate changed in the past few decades, it is important to pursue detailed investigations of the prevalence of this parasitic myiasis, as there are few such literature data for the Southern region of Serbia. One should also not ignore the fact that species of the genus Hypoderma can cause myiasis in humans as well.

The aim of the study was to evaluate and adapt the PCR-based protocol that utilizes the developed serotype-specifi c primers to identify Salmonella enterica species and its serotypes that are most frequently isolated from poultry samples in Vojvodina. Using the slide agglutination test, 64 and 33 out of 107 Salmonella isolates were identifi ed as S. Infantis and S. Enteritidis, respectively, while ten isolates were identifi ed as eight different Salmonella serovars. Using the same isolates, presence of 993-bp (bcfC gene), 636-bp (steB gene) and 293-bp (sdf locus) amplicons in multiplex PCR unambiguously identifi ed 31 isolates as S. Enteritidis. Two isolates identifi ed as Enteritidis in slide agglutination test were not identifi ed as such in PCR-based approach since they both were missing 293-bp long PCR product. Thirty-nine isolates produced a 727-bp amplicon in the specifi c simplex PCR, and thus were identifi ed as S. Infantis. The greatest discrepancy in comparison to the results of conventional serotyping has been observed in the case of S. Infantis, since 25 more isolates were noted as S. Infantis by conventional serotyping. Seven isolates, with unexpected PCR profi les stayed unidentifi ed by molecular typing, although they were serotyped as S. Typhimurium (1) and S. Infantis (6). S. Gallinarum serovar has to be additionally confi rmed, since it shares the same PCR profi le with S. Livingstone. Clearly, PCR-based identifi cation has to be thoroughly checked, verifi ed and adapted if it is to be applied as the routine identifi cation protocol.