There have been tremendous advances in animal pharmaceuticals since 1964. Yet, you commonly hear: “With all the new wonder drugs and vaccines, why haven't our sickness and death loss rates dramatically improved?”
Continued health challenges haven't been due to lack of applying products. The most I've heard of is nine injections at processing on feedlot arrival. And, when cattle get sick, four or five different things may be used at once.
Why don't these wonderful, multiple-pronged plans drop our morbidity and mortality to almost nothing?
Let's look at therapy
We have many choices to treat cattle today. My last count of approved products for bovine respiratory disease (BRD), for instance, was 14 different antimicrobials, with multiple forms.
Yet, for diseases such as calf scours, we still lack consistently effective, labeled treatments. Our best results in scours therapy come from rehydration and addressing the acid/base status of the blood.
For all our sophistication, we still are confused. For example, in BRD therapy, we equate the drop in fever related with successful antimicrobial treatment to dropping the fever artificially with some type of anti-inflammatory drug.
The former is the animal's natural response when fever is no longer necessary. The latter removes a natural and beneficial response to infection, which improves the appearance of the animal prematurely. The lure of management through a needle is so strong, we've forgotten how the animal and its immune system interact.
Role of prevention
We have plenty of vaccines — but don't assume there's a field-effective vaccine for every pathogen.
There's still a difference between vaccination and immunization. Even with today's advancements, vaccinating the animal doesn't necessarily mean protection.
We're also learning more about nutritional interaction with disease and the importance of animals' trace-mineral status. However, we've adopted the mantra that “if some is good, surely more is better.” And, we still have search parties out for the immunostimulant panacea that will make all immune cells above average.
It's hard to take promising lab findings into the field and get results. But, there is one way we can optimize immune resistance to disease in our cattle. That's genetic selection.
If you're buying low-end trader cattle, there isn't enough magic from the animal health industries to change what they are. Analyze morbidity and mortality data with a statistical process control approach, and you will find that different groups of cattle within source types aren't really that different over the long haul.
We have good groups and bad groups within the typical highs and lows. Often, we mistakenly attribute good groups to recent changes in our management wizardry. And, we comment on how much worse our bad groups would have been if not for the eye of newt and skin of toad.
Don't get me wrong. Some vaccines, antimicrobial interventions and management strategies make a difference when properly used. They can, and should, be used as part of a prudent management program. But, they're no substitute for genetically selecting for health performance as well as carcass performance.
Our mistake is that we often visualize antimicrobials and vaccines as a huge bulldozer pushing around the beachball of disease-animal interactions. We tend to attribute natural resistance and recovery to the effects of our interventions. In fact, we're decreasing disease occurrence and increasing recovery by relatively narrow margins in many cases.
The next 40 years
The future's biggest bright spot will come from using electronic ID technology to enable cattle producers to select for health performance. That will require a system where the feedlot health data consistently flows back to the herd of origin.
This approach is available now. If you keep heifers, why not pass over those with histories of illness? What are we doing when we place cattle into the breeding herd that barely survived with intensive therapy, or whose offspring required multiple treatments during the feeding period?
If you can keep track of bulls for each calf, keep track of illness rates by both dam and sire. Genetic analysis technology has advanced to where you can figure this out even with multiple bulls on a pasture.
Linking genetics to carcass quality and growth performance is becoming the industry standard. The winners will be those who work within a similar system, one for health performance.
Mike Apley, DVM, PhD, is an associate professor of beef production medicine at Iowa State University in Ames.