Despite significant improvements in herd and individual cow performance, most dairy managers and veterinarians will agree that ketosis and displaced abomasums (DAs) remain a persistent challenge. High rates of ketosis after calving and DAs in a herd are closely linked, and in most cases, fatty liver and liver metabolism is closely related to ketosis.
Several research papers presented recently at the American Dairy Science Association and the International Conference on Production Diseases in Farm Animals addressed these topics. And a review of that research reveals three key areas that could help improve transition-cow health.
1. Look beyond the diet
More and more research highlights the close relationship between nutrient metabolism, the immune system, and the neuroendocrine system. For example, adipocytes (fat cells) not only function as energy-storage cells, but as endocrine- and immune system cells. They can secrete the hormone leptin or an immune mediator known as tumor necrosis factor. These substances can impact other tissues and organs, including the brain and liver.
Meanwhile, inflammatory proteins may be closely related to the development of fatty liver and, thus, ketosis.
Factors that contribute to stress and/or inflammation in cows also may contribute to an increased rate of ketosis, fatty liver, and displaced abomasum. So, look at other areas of management besides diet.
2. Minimize the DMI decline
Cows that develop ketosis and fatty liver tend to have lower dry-matter intakes prior to calving. Now a growing body of research shows that the amount of the decline in dry-matter intake is more important than the absolute level of intake in triggering these problems.
In other words, a moderate intake with a small decline prior to calving is better than a high intake with a large decline. Therefore, a dry-cow diet that is intermediate in energy and fiber between what has been commonly recommended for far-off and close-up dry cow groups may work best in order to optimize dry-matter intake and minimize the drop.
This is the same strategy used by producers who manage cows for shorter dry periods (30 to 40 days) rather than the traditional 60 days.
3. Nutritional tweaks
Once fat gets into a cow’s liver, it gets out very slowly.
Researchers have searched for products that can enhance the metabolism of fat in the liver. So far, rumen-protected or encapsulated choline shows promise. The encapsulation process protects choline from rumen degradation, and allows it to be absorbed intact. Evidence presented this summer at the animal science meetings showed a clear benefit from feeding choline in reducing liver fat, improving production, improving reproduction and reducing ketosis. Choline appears to enhance removal of fat from the liver.
What you can do
Based on this latest research, I see several strategies that you can use to reduce ketosis, fatty liver, and, thus DAs on your farm. They are:
Minimize stress and inflammation around the time of calving, including social, environmental, and nutritional stress.
Consider shorter dry periods if your level of management is up to it. This will allow you to feed a diet that minimizes dry-matter intake depression at calving.
Feed rumen-protected choline during the transition period to help prevent fatty liver and enhance production and performance.
Ask your veterinarian about these new research findings to see if one, or all, of these strategies could help improve transition-cow health on your dairy.
Brian Gerloff is a veterinarian and operates Seneca Bovine Service in Marengo, Ill.