Death rates of adult cows on U.S. dairies have risen steadily over the last couple of decades. When calculating death losses as a percent of rolling herd inventory on an annual basis, it is now typical for dairies to have 8 to 10 percent mortality. If we look at literature from 30 to 40 years ago, it appears that 1 to 3 percent mortality losses were typical. Unfortunately, this feature of dairy animal performance has not been historically monitored as an important aspect of herd management, and there are no established benchmarks or targets.

Garry frank
Professor - Department of Clinical Sciences / Colorado State University

My colleague Craig McConnel and I at Colorado State University have been studying adult cow death losses on dairies for several years. We started focusing on this problem after observing that death losses on several farms were much higher than we had expected and after several Colorado producers identified such losses as a big concern.

For some producers, cow deaths seem frustrating or baffling, and they do not see a means to manage them. They feel they have done so many things right and still there are more losses than there should be.

In our research projects we have performed post-mortem exams, pursued diagnoses, looked for relationships between death loss and farm management features and evaluated contributions of common dairy diseases to these losses. Although typical death losses are in the range of 9 percent, there are dairies that consistently maintain death loss around 2 percent, and others with death losses around 16 percent.

Dairies with high death losses also typically have high levels of cow disease occurrence, but this variation in mortality rates between dairies is not attributable to any one or several specific diseases. Nor is there a single management feature, such as a vaccine program or an approach to down cow disposal, which can explain the differences.

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This level of farm-to-farm variation shows differences in management, and I believe it is time to reconsider some aspects of management style that can have profound influence on dairy production and cow welfare.

Years ago, when I was a young veterinarian faced with a bad outcome in a cow I had treated, the owner consoled me by shrugging and commenting, “Young man, if you don’t want any cows to die on your farm, don’t own cows.”

I recognized the truth of this sentiment – death is a part of life, bad things occasionally happen, and you can’t have complete control of all events. But this attitude of “stuff happens” does not work when death rates are high. Our findings show that death losses can be managed and reduced, but only if we modify our approach to cow health care and health information.

A big shift in dairy management over the last 30 years has been the adoption of “least-cost” approaches to decision-making. Today’s focus on “least-cost business” is a manifestation of the reality that most dairy producers are commodity producers and “price takers” rather than “price makers.”

It is easy to conclude that the only way to make a consistent profit is to keep the costs of production as low as they can possibly be. An extreme interpretation of this mentality promotes a drive to lower costs without sometimes seeing the expense of a less desirable outcome.

However, I would suggest all dairy producers are familiar with a different strategy that demands “high quality” first and “least cost” second. The prime example is least-cost ration formulation in mixing a TMR. Nobody would consider buying the cheapest possible feed ingredients as their primary strategy, or their milk production would plummet.

Instead, the best ration is formulated, and then the lowest cost is pursued to formulate that ration. I think it is easy to get too focused on the cost of something and miss the value, or perhaps the investment value of that same thing.

How do dairy producers approach the delivery of individual cow care and medical attention? Is it the least-cost method, or the high quality at lowest cost method? How do producers make decisions about veterinary intervention, about workforce size, about maternity pen management and transition cow management, about lameness management?

All of these decisions play roles in the promptness and efficacy of cow care and cow health procedures, and all of them are related to the number of cows that get sick, that are treated promptly and appropriately and that recover successfully from health challenges. How much time do well-trained animal health professionals spend on dairies, how much of that time is focused on health management beyond reproduction, and how much do dairy producers value veterinary intervention in animal health monitoring?

In the veterinary medicine field, the last several decades have seen a strong shift towards a focus on “production medicine.” There is no question that an emphasis on herd health, computer record-keeping and herd analytical tools are extremely useful, but I feel the pendulum has swung too far in this direction. The fact remains that individual animals get sick and individual animals die.

I have been told on multiple occasions that individual animal medicine is a thing of the past. I have been told by some veterinarians that they do not need to perform a necropsy to know why a cow died, because most times they can figure out the death loss from the records. Records analysis is only useful if the data analyzed is accurate.

For most dairies a cause of death is not entered, or the entry is determined by a worker or owner without veterinary consultation. In other words, we are not thorough enough in evaluating cow death to recognize where some details of management need to be improved.

To have “high quality at low cost” management, we need to have better scrutiny of cow health so that management changes can be made to avoid cow death. This means more veterinary involvement to provide high-value investment rather than simply least cost. How much more successfully could dairy cow health challenges and death losses be managed if there were more attention to the details of individual cow events?

Clearly the on-farm death of a cow is bad because it represents both the tragic loss of a production unit – the cow – and a financial loss in future revenue. There are many reasons a cow can die on-farm. Almost all on-farm deaths represent an endpoint for animal suffering, because very few cows die in their sleep from old age.

To me, this dimension of high rates of on-farm mortality is at least as important and at least as worthy of discussion as the financial loss the death represents. Outcomes are highly dependent on where we focus, and perhaps we need to rethink how much we focus on capturing more specific information about the cows themselves.

From our studies of adult dairy cow mortality, we have concluded there are two critical steps toward decreasing losses. First, we need to increase producer awareness of the significance and impact of these losses. Financial concerns are certainly important, but assuring our commitment to animal well-being as a primary focus of management decisions is equally important.

The producers I know who maintain death losses below 3 percent take every single death as a tragedy and an opportunity to evaluate management and to maintain their commitment to the welfare of the cows on their dairy.

Second, we need to scrutinize each death for the information it provides. This means a renewed focus on details of individual animals. It means a renewed commitment to veterinary involvement in the aspects of cow health that contribute to death losses.

This time and labor investment should be seen as “high value” and not relegated to “least cost.” In our experience, consistent post-mortem examination and monitoring provides information that producers use to decrease the problem. PD

Garry is a professor and coordinator of the Integrated Livestock Management Program at Colorado State University.

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Franklyn Garry
Professor
Department of Clinical Sciences
franklyn.garry@colostate.edu