Is More Always
Better With
Animal Health?
by W. Mark Hilton
W
hen the subject of herd health surfaces, phrases like, “I never
compromise on the health of my cattle” or “I don’t cut
corners on my health program” are common. I like those statements,
but the frugal part of my DNA (actually the majority) and the
scientific part ask, “Is this ideal?” Let’s look at vaccination, antibiotics
and deworming .
The “I vaccinate for everything” plan is rarely correct. Yes, calves
that are unweaned, not vaccinated or dewormed, and that may have
come from a herd where nutrition was not optimal, have a high risk of
developing bovine respiratory disease (BRD). I get that. I also know
that the calf ’s immune system may not give an optimal immune
response if we give too many antigens at once.
A calf does not need infectious bovine rhinotracheitis (IBR) virus
vaccination in multiple routes or types of vaccine. If you are giving a
modified live virus (MLV) both intranasal (IN) and injectable at the
same time, one can be eliminated. The same can be said if you are
using both a MLV vaccine (IN or injectable) and a killed vaccine at
the same time. IBR vaccine is an excellent immunizer, but doubling
up at once can overwhelm the immune system.
Giving high-risk calves a booster dose of BRD vaccine 14 to 21
days after the initial vaccination used to be routine. Now we are
questioning that practice.
If the cattle are hitting their target on feed consumption, and
sickness is below what is expected, your herd health veterinarian
should reassess the timing or need for a booster. The phrase, “always
ask the cattle” allows the veterinarian and you to decide the timing
or need.
Don’t waste money on antigens you don’t need. Vaccinating for a
disease that is never diagnosed in your area is a waste of money and
the calf ’s immune system. It costs the calf in protein and energy to
mount an immune response. If a disease is not present, that protein
and energy could have been better used for growth.
If you have health history for your purchases, that can help to
eliminate redundant vaccinations. If, for example, a calf has already
received two doses of clostridial (blackleg) vaccine , there would be
almost no reason to give another. A seasoned DVM told me early in
my career, “Never put a hole in an animal unless it is necessary,” and
I have never forgotten that.
Am I saying you should start eliminating some of your vaccines
in your protocol? Absolutely not. Meet with your herd health
veterinarian and go over your protocol line by line. If something
needs to be eliminated (or added), your herd health veterinarian is the
best person to help you balance protection and cost.
Some producers use multiple antibiotics concurrently to treat BRD.
I have never seen a study that advocates that practice. We have a
multitude of excellent antibiotics to treat BRD, and each is approved
for use alone.
Yes, we have seen antibiotic resistance to our pharmaceuticals
develop over the past 30 years for a variety of reasons, but the most
common reason for treatment failure is not due to using the wrong
antibiotic or combination. Cattle are prey species, and they can “hide”
that they are sick. Initiating treatment later in the disease process
continues to be a major factor in treatment failure.
Research shows that using multiple drugs simultaneously is
effective and economical when deworming calves as they enter the
backgrounding yard or feedlot. Resistance to macrocyclic lactones
(avermectin-type drugs) is common, and using an injectable
macrocyclic lactone and an oral benzimidazole (white dewormer)
upon arrival is commonplace.
Please do not make any changes to your current health protocol
based on this article. The goal is to ask you to pause and think about
everything you do from a health perspective, and then schedule a
meeting with your herd health veterinarian.
ABOUT THE AUTHOR: Hilton, DVM, PAS, DABVP (beef cattle
practice), is a veterinary technical consultant, Elanco Animal
Health; and clinical professor emeritus, Purdue University College
of Veterinary Medicine.
• APRIL 2020
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