Milk fat depression (MFD) refers to a reduction of fat content by up to 50% when milk yield and other milk components remain unchanged.
Causes of MFD
- Diet composition: feeding ruminants a diet that is high in readily fermentable carbohydrates or plant oils can lead to MFD. These diets alter rumen fermentation patterns, reducing the production of fatty acids needed for milk fat synthesis.
- Ruminal acidosis: excessive consumption of fermentable carbohydrates can lead to ruminal acidosis, disrupting rumen function and reducing the synthesis of milk fat precursors.
- Microbial changes: changes in the microbial population of the rumen due to diet or other factors can affect rumen fermentation and subsequently decrease milk fat production.
- Heat stress: heat stress can reduce dry matter intake and alter rumen fermentation, leading to decreased milk fat production.
- Metabolic disorders: metabolic disorders such as ketosis or fatty liver syndrome can disrupt energy metabolism and decrease milk fat synthesis.
- Stress: poor management practices, such as abrupt changes in diet or feeding frequency, can stress cows and contribute to MFD.
Losses incurred
- Lower milk fat content, combined with potentially reduced milk prices, can lead to a direct loss of income for dairy producers. For instance, a 200-cow herd that decreases from 3.6% to 3.3% milk fat would lose €114/day. Therefore, mitigating milk fat depression is crucial to increasing dairy farm profitability. (Koch, L. E., and G. J. Lascano. “Milk fat depression: etiology, theories, and soluble carbohydrate interactions.”)
- Greater losses occur when the animal experiences a severe form of the disease. Such diseases include acidosis, abomasal displacement, laminitis, mastitis, etc. As a result, the cattle require complex treatment, and sometimes even a productive cow with high genetic potential has to be culled. Losses per cow can vary from €30 to €300.
How do we detect it?
The Brolis in-line milk analyzer measures the composition of each cow’s milk during every milking. The Brolis HerdLine system detects milk fat depression by identifying a significant decrease in the fat-to-protein (F/P) ratio. Additionally, the system considers factors such as the milk yield, content of other milk parameters, the cow’s breed and lactation period in order to make accurate assessments.
Prevention of MFD
- Adjusting the composition of the diet to reduce the intake of highly fermentable carbohydrates or plant oils, which can contribute to MFD. Adding buffers or other rumen modifiers to help stabilize rumen pH and improve fermentation efficiency.
- Increasing the proportion of dietary fiber to promote rumen health and stabilize rumen fermentation.
- Regularly monitoring milk fat percentage and other milk components to assess the effectiveness of treatment strategies.
Case on the farm: detection and treatment of MFD
- The cow entered a high-risk state of MFD when her fat percentage dropped to 2.7% on 15th of October.
- The cow wasn’t showing any clinical signs at that point.
- On 17th of October, a veterinary doctor diagnosed subclinical mastitis in this cow and administered treatment.
- After a few days, the cow was healthy again, as we can see on her lactation graph.
Find out about other health disorders detected by Brolis HerdLine
