How We Health Test Our Dairy Cows (And Why It Matters)
One of the most important things we do on our farm - behind the scenes - is health testing our dairy cows. There are two ways we health test cows - with a milk sample and with a blood (serum) sample. The two separate tests guarantee we know that our cows are healthy. It’s not flashy work, but it’s vital. Healthy cows make healthy milk, and that starts with knowing exactly what’s going on inside each animal’s body.
Here’s a simple look at what we test for and why it matters to us, and why it should also matter to you and your family:
BLV (Bovine Leukemia Virus)
Sometimes referred to as “leukosis.” This is a virus that affects a cow’s immune system. Some cows can carry it without showing signs, but it can still weaken their health over time. It can also be passed to other cows by sharing & reusing needles or passed in utero to the calf. We test for BLV because we want strong, thriving cows - not ones silently battling illness. I’ve been told more than once when looking at cows to buy and read posts and articles from seasoned dairy producers that BLV doesn’t matter…it’s in every herd and there is no way to get rid of it. It’s not classified as zoonotic (can be spread from animals to humans) but there is research being done that suggests that BLV is linked to illness in humans, and that suggestion is enough for me to decide I don’t want it here.
BVD (Bovine Viral Diarrhea)
Despite the name, BVD is more than just a stomach bug. It’s a serious virus that can affect a cow’s immune system, reproduction, and overall vitality. There are two types of BVD... type-1 and type-2, with type-2 being the more serious variant. Calves born to BVD-positive cows can be especially vulnerable. We test to keep it out of our herd entirely.
Johne’s Disease
This one is a slow-developing bacterial disease that affects the intestines. And it’s lethal. Johne’s is hard to spot early on, but it rears its ugly head over time as the cow ages. This disease usually presents itself as weight loss and diarrhea, and eventually leads to death. It also passes from cow to calf easily. We screen for it because prevention is key - the bacteria that causes Johne’s can live for years in the soil, and once it’s in a herd, it’s tough to get out.
Contagious Mastitis-causing Bacteria
We also have the lab run a multi-panel check for 16 different strains of bacteria that can lead to mastitis, a painful infection in the udder. Mastitis frequency has been tied to genetics, which means that a cow that frequently gets it or doesn't get it can pass that trait on to their daughters. But mastitis cases are also an indicator of cleanliness and sanitation practices. Mastitis that results from dirty living quarters and unclean milking equipment is called environmental mastitis. There are a few different strains, but the most commonly feared is Staphylococcus aureus - often called “Staph A” for short.
Staph A is serious business. It can cause chronic infections that are hard to treat and can permanently damage the udder. It’s contagious, too, so it can spread from an infected cow to a healthy cow. This happens when a calf nurses from other cows that are not it's mom. If a healthy cow's calf nurses from and infected cow and goes back to nursing its mom, the calf can transfer the bacteria. Or vice versa - if the infected cow's calf finds another healthy cow to nurse from, the bacteria can spread. This is called "robbing" and it's one reason dairy farms bottle raise calves rather than calf sharing. Those dairy cows are just so darn nice, they don't care whose calf they are feeding!
We test for all strains of bacteria that cause mastitis to protect our cows and ensure the milk we offer is clean, safe, and high quality, especially since we’re keeping it in its original raw state.
A1/A2 Beta Casein
This one isn’t a disease; it’s a genetic trait. Cows produce either A1 or A2 beta casein protein in their milk. Cows' milk can be A2A2, A1A1, or A1A2. If you think back to high school genetics, do you remember Punnett squares? (As a former teacher, I LOVE genetics and think Punnett squares are so fun.) That’s how this trait is presented…one gene from the mom and one gene from the dad.
The results of this test don't factor in as far as which cows we milk, keep, or breed; but we test for this just to know their status strictly for informational purposes.
At the end of the day, we’re not just providing people with milk - we’re offering health and nourishment and a way to obtain a complete food in its most natural state. Healthy food starts at the source, and we ensure that by giving our cows the best care possible. Regular health testing gives us the peace of mind that we’re doing right by them, and by anyone who chooses to use our products.
If you ever have questions about our cows or our milk, just ask. We love talking about the process, because we believe you deserve to know exactly what you’re bringing into your home. And remember, no matter where you are sourcing your farm-raised food from (even if it’s not us) you deserve to know exactly where it comes from, how its raised or grown, and how it’s handled before it gets in your hands. NEVER be afraid to ask the questions you have every right - and responsibility - to ask when it comes to food you are giving your family.