## 1 Introduction
This media combination, which inhibits the growth of bacteria other than _Salmonella_, also gives important information on some principal differential biochemical characteristics, such as non-lactose fermentation and hydrogen sulfide (H\({}_{2}\)S) production [22]. Exceptions are _Proteus, Pseudomonas_, _Citrobacter_, and _Hafnia_[23; 24] species resembling _Salmonella_ spp., and also _S. arizonae_ and _S. diarizonae_, that ferment lactose or variably produce H\({}_{2}\)S. False-negative cultures may also occur if the low number of _Salmonella_ bacteria present in a sample is suppressed by the overgrowth of other bacteria. Thus, the quality of a sample, culture medium selectivity, and also the incubation conditions affecting, perhaps, the expression of certain biochemical characteristics, influence prevalence. In order to minimize workloads and false results, many chromogenic agents have been developed to aid with the differentiation of suspect colonies [22; 25; 26]. Generally, chromogenic agars contain a combination of chromogenic substrates metabolized only by the targeted bacteria species, which produce colonies of distinctive coloring [27]. They are, however, serovar-dependent, thus frequently leading to false results [28] and they are also relatively expensive, increasing the costs of routine laboratory procedures for animal testing [29]. In addition, the development of culture media promising increased sensitivity and specificity increases inter-laboratory inconsistency if standard procedures are not applied [30]. The various serological, biochemical and molecular tests applied require 5-11 days for a definitive confirmation of a suspect isolate [8]. _Salmonella_ spp. are generally considered to be non-lactose-fermenting (NLFs); Gram-negative rods; motile due to peritrichous flagellae (excluding serovars Pullorum and Gallinarum); glucose fermenting, with the production of acid and usually gas; positive to catalase, methyl red and Simmons citrate reaction; and negative to urease, lysine decarboxylase, indole, oxidase, and Voges Proskauer (VP) tests. They produce H\({}_{2}\)S and ferment L-arabinose, maltose, D-mannitol, D-mannose, L rhamnose, D-sorbitol (except ssp VI), trehalose, D-xylose, and dulcitol. These tests are now available in commercial identification kits, such as the API 20E (BioMrieux) or the MicrogenTM GnA+B-ID (Microgen Bioproducts Ltd., Camberley, Surrey, UK) systems. The small amounts of media used in these systems reduce both cost and workload. Once a strain is identified as possibly belonging to _Salmonella_ spp., this requires confirmation by serological testing for the detection of somatic (O), flagellar (H), and virulence (Vi) antigens possessed by salmonellae. However, accurate identification of a serovar is possible when the Kauffman-White Scheme is performed in a Salmonella reference laboratory where, in the case of doubtful results, phage typing and a genetic profile can be also obtained by experienced microbiologists using the most appropriate culture methodology and media. In consideration of the above, the objective of the present reporting is the dissemination of knowledge acquired from the observations and diagnostic difficulties resolved using the culture methods recommended by ISO 6579-1:2017 for the isolation of _Salmonella_ spp. from swine samples collected at slaughter.