Emerging animal health issue

The Ministry for Primary Industries have contacted us regarding an emerging animal health issue relating to Salmonella Bovismorbificans.

Salmonellosis has long been recognised as an important cause of disease in cattle. However, based on the information MPI collects from the New Zealand’s veterinary diagnostic laboratories, they have noticed an increase in the reported incidence of Salmonellosis in dairy cattle since 2015, most notably involving the serotype Bovismorbificans.

Prior to 2015, S. Bovismorbificans was a rarely reported serotype in cattle (2003-2014 n=8). Since 2015, they have noted an increase in reported cases (2015-present n=834).

Because their data relating to impact relies on the information provided in veterinary submission forms (and some fields are often not completed), it is difficult to make an estimate regarding the impact of this serotype on the outbreak farms.

Sporadic cases and outbreaks have been reported in both adult dairy cattle and in calves. While cases do get reported year round, the majority occur in spring with a smaller peak occurring early autumn.

Most regions of the country have experienced cases, but the main areas from which cases have been reported are the Waikato, Manawatu-Whanganui and Taranaki, with increasing reports of cases also from Canterbury and the Bay of Plenty.

The extent of the issue is difficult to estimate in sheep, due to a limited amount of data; but, it is clear that there has been an increased number of reports in this species also.

To help MPI better understand the impact of S. Bovismorbificans, we ask veterinarians to ensure they complete ALL the fields on laboratory submission forms, especially the fields that relate to number of animals at risk, number affected and number dead.

Along with this increasing trend in animal cases, ESR has reported cases of S. Bovismorbificans in humans. This emphasises the importance of this organism (and Salmonella generally) as a zoonotic pathogen and a potential risk to those working with affected animals.

MPI recommends farmers seek veterinary advice about Salmonella, including vaccination, and the ongoing need for good farm hygiene practices.

If you missed it, also see the article on our website from last month’s newsletter regarding salmonella abortions in cattle.  If you have any questions or require further information, don’t hesitate to give your local pathologist a call to discuss: