Background: Mycoplasma hyorhinis (M. hyorhinis) is a bacterium commonly found in the upper respiratory tract of healthy pigs and an agent of polyserositis and polyarthritis. Moreover, it can carry antibiotic resistance genes (Wu et al, Vet. Microbiol. 76: 25–30, 2000). Economic losses caused by M. hyorhinis can be reduced by antibiotic therapy, however, isolation and antimicrobic susceptibility profile are rarely performed. Case presentation: The present report describes a case of pericarditis caused by M. hyorhinis in a weaned piglet with respiratory symptoms and reduced growth performance. At post mortem examination, the main macroscopic finding was a severe fibrinous pericarditis and M. hyorhins was the only agent isolated from the pericardial fluid. In this strain, Minimum Inhibitory Concentration (MIC) determination revealed resistance to various antimicrobial molecules such as erythromycin, tylosin and tilmicosin. Conclusion: This paper highlights the importance of including M. hyorhins in the differential diagnosis of polyserositis in swine. Moreover, due the possible presence of multidrug resistance, the determination of antimicrobial susceptibility pattern should be performed on a regular basis.

Leptospirosis is a worldwide-spread zoonosis causing disease and death in dogs and in humans. A Leptospiral infection has been recorded in several wild carnivore species in Europe, but tissue pathological changes were not commonly described. The Grey wolf (Canis lupus) has been expanding its distribution range in north-eastern Italy during the last decade. A young wolf, representing the first individual handled in the region, was found road-killed and then submitted to necropsy. Pathological changes included erosive lesions of gingival mucosa, mild liver enlargement, and multifocal degenerative-necrotic areas along with hyperemic reactive lesions; multifocal interstitial nephritis and multifocal lung hemorrhages were observed. A Polymerase Chain Reaction (PCR) able to detect pathogenic species of Leptospira performed on a kidney sample was positive. Serological reactions for serogroup Gryppotyphosa (1:6400), Pomona (1:800), and Icterohaemorrhagiae (1:200) were evidenced by MAT. Genotyping by Multilocus Sequence Typing (MLST) performed on detected Leptospira characterized it as belonging to Sequence Type (ST) 117, which refers to L. kirschneri, serogroup Pomona, serovar Mozdok. Regardless of the role of Leptospira infection as an eventual predisposing factor to the road killing of this wolf, to the best of the authors’ knowledge, this is the first report of Leptospira-induced pathology in a wolf in Europe. Surveys on Leptospira infection in free-ranging wildlife species should be pursued in order to achieve further epidemiological knowledge on the circulation of the Leptospira strain.

Leptospirosis is a (re-)emerging and global zoonotic disease. Given the complex host-pathogen interaction and the numerous environmental risk factors related to the transmission, a One Health approach to both disease prevention and control is needed. Occurring at the human–cattle–environment interfaces, bovine leptospirosis represents a zoonotic risk for the professionals in the field, besides being a potential cause of significant economic losses due to the bovine reproductive disorders. Although climatic change is a potential factor in exacerbating the risk of leptospirosis in Europe, this disease remains largely neglected, with several knowledge gaps in research, investigations, and diagnosis of bovine genital leptospirosis syndrome across the continent. The present report describes the results of the diagnostic investigations on a case of chronic bovine leptospirosis in a breeding bull. Following the seroconversion to Leptospira Sejroe var Hardjo after the arrival of the animal in a quarantine facility, a monitoring plan including both serological/molecular analyses and a therapeutic protocol was undertaken. The bull exhibited a persistent seroconversion and a repeated positivity for Leptospira to real-time PCR in urine samples, indicative of a chronic shedder pattern. This report emphasizes the diagnostic and management challenges in the context of such a complex but frequently overlooked disease.

Two 7‐day‐old suckling piglets were submitted to the Diagnostic Laboratory of Pordenone of the Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) for pathomorphological examination. The piglets had died suddenly, showing blood‐stained discharge from nostrils and mouth, without any sign of crushing. Macroscopic examination revealed dark and solid pneumonic lesions in the diaphragmatic lobes associated with fibrinous pleurisy. Actinobacillus pleuropneumoniae was isolated from lesions; porcine reproductive and respiratory syndrome virus (PRRSV) was detected by RT‐PCR from the lungs. A pleuropneumoniae is a known cause of pneumonia and pleurisy in fattening and weaned pigs but, although colonisation of tonsils is well documented in suckling piglets, the clinical form of the disease in infant pigs has been infrequently described in endemically infected farms. Such events may be a consequence of the introduction of a new A pleuropneumoniae serovar, an incorrect gilt immunisation for this pathogen or inadequate colostrum intake by piglets.

Porcine reproductive and respiratory syndrome (PRRS) is a global challenge for swine production. Due to its high variability and limited cross-protection, immune-based control measures are only partially effective, emphasizing the critical role of biosecurity. A prior study on Italy’s largest integrated pig production company demonstrated the effectiveness of hierarchical organization in separating pig flows but, through biostatistical estimations, highlighted vulnerabilities, particularly the role of non-integrated farms in introducing new variants into the integrated system. Over 500 PRRSV sequences from integrated and non-integrated farms in central-northern Italy were analysed in the present study using phylogenetic, phylodynamic, and phylogeographic approaches. Two main PRRSV clades were identified circulating in both systems, with non-integrated farms hosting a broader viral population. The migration rate of PRRSV from non-integrated to integrated systems was found to be 2–10 times higher than the reverse, depending on the clade. Geographical migration patterns and environmental factors influencing viral dispersal were evaluated. Despite being located in the same geographical areas, non-integrated farms exhibited higher viral dispersal speeds, marked by bursts over time. Although some differences in geographical persistence and dispersal risk factors were observed among clades and categories, road networks and pig population density were the most important and shared determinants. These findings confirm the critical role of non-integrated farms in PRRSV epidemiology, posing a risk to integrated systems due to their distinct persistence and spread determinants. The study underscores the necessity for regional collaboration and information sharing to improve infection control and reduce viral recirculation between different productive systems.