Abstract
Salmonella is diffused worldwide, and Salmonella enterica subsp. enterica is spread worldwide with many serovars associated with the infection of domestic bovines. The most spread are S. Dublin, S. Typhimurium and S. Infantis. S. Napoli is, however very rarely reported in domestic ruminants. Here, we report an outbreak of S. Napoli on a dairy cow farm in Northern Italy (Piacenza). A total of 18 S. Napoli isolates were recovered from aborted fetuses, feces, tissues and environmental samples. Whole genome sequencing suggested that all isolates belonged to the same cluster. After the application of stringent biocontainment and biosecurity measures, no further cases were reported. However, four months after the first case, the serovar was still isolated in environmental samples, underlying the importance of adopting the correct biosecurity and biocontainment measures in order to prevent the circulation and transmission of Salmonella within the farm.