Why did that cow die?
Cow deaths have increased on many dairy farms yet often the reasons for deaths are not fully explored. The opportunity to learn how to prevent future deaths is an area that is ripe for improvement.
For various reasons, the rate of cow deaths on dairy farms has been increasing in recent years, with many herds running 8-10 percent losses, and some with significantly higher death rates. Frank Garry of Colorado State University reported at the 2013 Tri-State Dairy Nutrition Conference that a review of death loss suggests that a 1-5 percent death loss is normal. In my experience as a Michigan State University Extension dairy educator working with dairy producers, I have observed that many producers have come to accept a higher than normal death loss because it has become their new normal, not because it can’t be reduced.
Slaughter cow prices are currently high relative to what they were for many years. Producers have been getting a good check for cull cows, particularly when those cows are heavy. But dead cows are worth nothing. A dairy can experience significant economic cost from cow deaths just due to lost market value. For example, a 200 cow herd with a 10 percent death loss rate would mean that 20 cows die each year. If the cull value of cows averaged $1,200, the annual loss of value would be $24,000.
Not only is a dead cow a significant loss of income, but she is an indicator of some problem that, if left unchecked, could affect more cows. Cows die for a reason and the reason usually does not impact one animal alone, it potentially impacts a group of cows. Understanding why cows die can be used to reduce the risk of other cows dying in the herd.
Other potential impacts of death loss include environmental impact, animal welfare concerns, loss of genetic progress and owner or employee physical and mental health issues. In his practice experience, Dan Grooms from the MSU College of Veterinary Medicine has personally witnessed high death rates leading to employee emotional and health problems.
In spite of this, very few cows are looked at (necropsied) to determine the cause of death. The National Animal Health Monitoring System (NAHMS) Dairy 2007 study reported that necropsies were performed on only 13 percent of dairy operations and on less than 5 percent of dead cows.
Dairy cattle record systems are of very little help in locating the problem as they are typically not configured to analyze cause and effect of deaths. Therefore, they do not have adequate ways to lead producers back to management changes that would reduce death losses. Developing better record systems for capturing and analyzing death losses should be a priority.
A study by Craig McConnell at Colorado State University found that although producers try to assign a cause of death, they are only accurate about 50 percent of the time. Producers were certainly more accurate in cases that involve more obvious causes, such as injuries resulting in death or severe disease states. But that meant that they were less accurate where an obvious cause was not apparent.
Garry reported that 50 percent of cow death losses are a result of causes that could be reduced through management changes. However, a lack of actionable information about the causes of death keeps those management changes from being made in a timely manner.
Based on this information, MSU Extension recommends that dairy producers take several actions.
- Assess potential problem cows and cull sooner.
- Keep good records of death losses and add both herd changes and cow information in those records that may help to identify patterns.
- Talk with your veterinarian about cow losses and decide on a plan to necropsy a percentage of animals that die and to target those that present more of a mystery.
- Make cattle death a time of learning for employees so that they can be more aware of factors that lead to deaths.
Future articles will discuss records, necropsy and education of employees in greater detail. Reducing cattle deaths by changes in management and actions will happen only when dairy owners place a higher priority on it. The time has come to make cow deaths a priority on all livestock operations.