(Note: This article has been edited and condensed.)
A surprising proportion of producers believe they run a closed herd.
The 2017 Western Canadian Cow-Calf Survey found that of approximately 25 per cent of respondents who did not vaccinate their cows and heifers against reproductive diseases such as IBR and BVD, over half said their reason was because they had a closed herd. Similarly, over 20 per cent did not vaccinate their calves against respiratory disease (BRD), and 30 per cent of those indicated having a closed herd was their main reason for not vaccinating.
Often a closed herd is simply interpreted as just being closed genetically, where replacements and cleanup bulls are all home raised, artificial insemination is the main breeding method if new genetics are desired, and non-home-raised cattle never enter the operation.
But like most things, it’s a little more complicated than that.
A truly closed herd will have no contact (even fenceline) with any other livestock or wildlife and will limit visitor/service provider access to areas where cattle are never present. In a closed herd, non-home-raised animals (even horses, dogs) never set foot on the ranch and any animal that leaves home never comes back. All personnel, visitors, and service providers are following extraordinarily strict biosecurity measures – almost exactly like those implemented in the swine and poultry industries.
You either have a closed herd or you don’t. Just like there is no such thing as ‘sort of pregnant,’ there is no such thing as a ‘pretty closed herd’ or a ‘mostly closed herd.’ Those herds are open.
While a closed herd is optimal from a biosecurity standpoint because it’s difficult to introduce disease to a completely isolated population, it certainly doesn’t mean you are home free as far as vaccination is concerned.
Let’s face it, fences break, gates get left open, and some cattle just seem bound and determined to end up places they’re not supposed to be. This can be devastating in a naive herd that hasn’t been exposed to disease through prior exposure or vaccination.
Even without running a closed herd, there are easy and practical things producers can do to limit the risk of disease spread. Vaccination and implementing basic biosecurity protocols (such as quarantines and boot washes) are key and more attention should be focused on keeping bull vaccinations current.
This article may ruffle a few feathers as the idea of a ‘closed herd’ or ‘one-iron herd’ is often a point of pride for producers.
I recently heard a veterinarian say during a presentation that closed herds are like unicorns, often talked about but seldom seen. A horse that has a cone strapped to its head is still just a horse.
Karin Schmid is ABP’s research and production manager. The full version of this article, including a list of questions on whether you have a closed herd, can be found in the BCRC Blog section at beefresearch.ca.