Ok, back to the case. So upon physical exam of these animals, I’ve noticed some clear nasal discharge (a good thing), normal temperatures, normal stomach movement, heart and lung sounds, normal manure and uterus discharge; pretty much completely normal physical exam for a fresh cow (new mom). So now what???
In veterinary school we often heard the phrase; “If you hear
hoof beats, think horses, not zebras.”
In my world, this means, if it looks like a duck, quacks like a duck and
walks like a duck, it’s probably a duck!
So, when I see bloody noses in cows, my first thought is usually; “did
they have a lung abscess/hematoma that popped from a previous pneumonia event?”
My second thought is “did someone hit
them with the skid steer pushing up feed?” If the answer to the first two
questions is no, then I turn to the zebras, the very important DO NOT FORGET ABOUT zebras, such as
Foot and Mouth Disease, Bluetongue and other foreign animal diseases that must
be reported to the state veterinarian, resulting in a very fast quarantine and Plum
Island certified veterinarians taking samples. EEEEEEEEKKKK!!!
A normal cow’s temperature ranges from 100-102.8 F. When they have temperatures as high as 105-106
F we often think immediately of viruses. Bacterial infections will raise a cow’s
temperature, but usually not as high as a virus will. These
high temperatures along with other cows in the herd having bloody noses in the
barn were most likely due to one of the 5 or 6 bugs associated with pneumonia in
cattle, also known as Bovine Respiratory Disease Complex, or BRD. When I received my finalized report for the
first round on blood samples taken, it looked as though these cows have a few
different bugs they are dealing with. The first bug is “Coronavirus.”
Coronavirus (Corona) is an old bug in a new form. More commonly Corona is known to cause
diarrhea in baby calves and winter dysentery in adult cows. It’s one of the
bugs that are always around in cattle and when we go looking for it, we find
it. To help a newborn calf deal with Corona, we vaccinate mom when she is very
pregnant and starting to make her colostrum. This way, the calf will hopefully receive
the protection it needs as starts life.
It is recently starting to show up in multiple cases of respiratory
disease in cattle of all ages. Unfortunately the vaccine used to prevent
diarrhea in baby calves, has not been seen to help much with adult cows with
the respiratory form of the disease.
There is lots of money going into research on corona and how it plays
along with the other common bugs associated with BRD in cattle. The other bug that seemed to be mucking the waters was IBR, Infectious Bovine Rhinotracheitis. The actual virus that causes IBR is Bovine Herpes Virus-1. This is another common bug found in the BRD complex in cattle. There are several good vaccines on the market for IBR and although these respiratory vaccines may not prevent the disease, they certainly lessen the severity of the disease.
For this particular
herd, we may need to re-evaluate the vaccination protocol to see how we can
help booster the first calf heifers’ immune systems. Cow’s that just had a baby need to have as
smooth a transition into being a milking cow as possible, and having high
fevers and dealing with pneumonia is something that definitely sets them
back. All the cows pictured are doing
just fine and the cows that had high fevers are doing much better. We continue to monitor temperatures and look
for bloody noses and hopefully as the outside temperature starts to steady, so
will the cows!