Do you know what causes about 50 percent of lameness cases in dairy cattle? Digital dermatitis. This disease is tricky to manage and can cause serious economic losses if not controlled.
A little over two years ago, a group of farmers asked me to answer three questions for them:
- How effective is an alternative footbath product that uses less copper?
- Can estrus detection technologies help me identify cows with hoof lesions?
- How do hoof lesions or warts affect cow feeding behavior?
My research team and I recently completed a study that aimed to answer those questions. We trialed a footbath product (AdVANTAGE) designed to enhance the effectiveness of copper sulfate at lower levels, thus reducing the quantity of copper sulfate needed to effectively manage digital dermatitis.
We integrated our work using a cow behavior monitoring system (CowManager). We conducted this two-year-long study at the Washington State University Knott Dairy Center. The dairy milks, on average, 170 Holstein cows twice a day. I hope by sharing what we learned, managing digital dermatitis will become easier on your farm.
Footbath product comparison
Because we traditionally use copper sulfate in our 50-gallon footbaths, we decided to test the copper sulfate-enhancing product against copper sulfate used by itself at the normal rate. We alternated use of the two products every four months. Copper sulfate footbaths started with 25 pounds of copper sulfate mixed with water, dumped after two milkings and used three days a week.
For the alternative product, footbaths started with 12.5 pounds of a copper sulfate and zinc sulfate mixture, plus 25 ounces of the product concentrate mixed with water, and we maintained these footbaths at a pH less than 5, dumped them after four milkings and used them four days a week (set up twice a week but kept in place for four milkings before dumped).
Once a month, we evaluated all cows’ rear feet in the parlor for hoof lesions. We recorded whether a lesion or swelling was present, if the lesion was active or digressing/regressing and lesion size (Table 1).
We focused on comparing the prevalence of hoof lesions and swollen feet for both products during the final month (fourth month) of each four-month testing period. Overall, we had fewer cows with active lesions (Figure 1) and fewer cows with large lesions (Figure 2) when we used the product.
We did not detect any differences in the percentage of cows with small or medium lesions between the two products.
Hoof health and cow behavior
We installed CowManager eartags on all lactating cows in order to collect behavior data that is very helpful for estrus detection and monitoring cow well-being. It is especially useful in helping our students identify changes in cow behavior.
Figure 3 shows a behavior graph snapshot for one of our cows, 2542. The graph shows you how much time the cow spent ruminating, eating, not active, active or highly active each day.
My rule of thumb is: I would like to see all lactating cows spend about 20 percent of each day eating. As you can see from the graph, 2542 was not reaching this target, especially when she was only spending 5 percent of the day eating. We kept a close eye on her and monitored her health.
On every hoof evaluation day, we collected behavioral data for each cow so we could match hoof health (related to lesions and swollen feet) with cow behavior. Cows with no hoof lesions or swelling spent an average of 13 minutes every hour (22 percent of time) eating, whereas cows that had a hoof lesion or swelling spent an average of 10 minutes every hour (17 percent of time) eating.
Let us think about this from a daily standpoint. Cows without hoof lesions or swelling spent 72 minutes more eating every day than cows that had hoof lesions or swelling. That is over an hour of lost feeding time for cows with hoof lesions. It is interesting to note the size of hoof lesions did not affect eating behavior in our study (Figure 4).
Another intriguing feature of the system is: It also records each cow’s ear temperature. The general thought is: As a cow’s ear temperature decreases, the rectal temperature increases.
We noticed in our study cows with hoof lesions or swelling had ear temperatures (about 69.8ºF) about 5ºF lower than cows without hoof lesions (about 75.2ºF). The relationship between ear temperatures and hoof lesions is something we plan to investigate in more depth.
Summary of findings
Overall, we found answers to our questions but now have new questions to pursue. We learned a footbath solution with lower concentrations of copper can be more effective than copper sulfate at managing large, active hoof lesions.
We learned estrus detection technologies that monitor cow behavior have the potential to identify cows with hoof lesions. We were surprised to learn cows with hoof lesions spend 5 percent less time eating than cows without lesions, and lesion size did not affect eating behavior.
Cows are prey animals that only show weakness when they have to. It is easier for us to identify cows with lameness than cows with small hoof lesions. Wouldn’t it be nice if we could use technology to help us identify those small lesions earlier and provide care earlier? Just food for thought.
I hope we helped you answer some of your questions about hoof lesions. Feel free to contact me with any questions or comments.