On the dairy and calf ranch, this is the time of year where we see an uptick in Salmonella cases, primarily in calves that are comingled coming from dairies and end up at the calf ranch. Salmonella dublin is like other Salmonella strains – they are fecal oral and capitalize on fecal shedding into the environment from carriers in the cow herd. Unfortunately, these carriers heavily shed right when both mom and calf are most susceptible – when mom has just calved and immunosuppressed. This means that if you have a history of Salmonella on the dairy, it’s most likely to be shed into your calving pen or fresh pen. It can also commonly be found as a contaminant of colostrum. This propagates the disease onto the calf who carries it into the young calf pen on the dairy or into the calf ranch. Salmonella dublin is unique to calves in that it can cause very severe disease, high fevers, and depression greater than other strains.
1. Clean, clean, clean.
You have heard me talk about cleanliness at nauseum if I’ve been out to your calf facilities, but that’s because most calf diseases, along with Salmonella, infect calves via manure contamination. Clean your calving pen, colostrum collecting equipment, and feeding equipment regularly. Salmonella and other scour pathogens will propagate on these objects and take advantage of the summer warmth, residual milk, and moisture associated with dirty equipment.
2. Reduce calf stress
Salmonella utilizes stressful times to overcome it’s host. Stress can come in many forms – weaning stress, other disease pressure, failure of passive transfer, moving stress, and heat stress can all play a role in disease. Ask yourself if you’re doing everything you can to reduce this for your calves.
There are lots of vaccines out there designed for the dairy cow. Each vaccine’s label is different, but the concept of pre-calving vaccination is the same – vaccinate cows once with a booster at least 8 weeks prior to calving. The dry period is preferred as Salmonella vaccines can cause milk drop in cows when lactating. This utilizes the dry period to put antibody into the cow’s colostrum for the calf. Additionally, this vaccination will reduce the amount of shedding in the fresh period and reduce risk of transmission. For vaccinating calves, there are safe, effective options that reduce the risk to the calf directly. We utilize cross protection between Salmonella typhimurium vaccine to directly vaccinate the calf. Just like the cow, this reduces fecal shedding and reduces the risk of infection, and if calves are infected, highly reduces clinical signs for the calf.
Salmonella is truly an ugly bug, but it’s preventable. If you are struggling with this in your calves or cows, give us a ring. I’d love to not have another Salmonella summer!