- Ketosis involves an increased concentration of ketone bodies in the blood and metabolism (hyperketonemia)
- Ketone bodies are formed when there is insufficient availability of glucose
- Dairy cows have restrictive glucose availability. Therefore, any energy shortage (= negative energy balance; NEB) can quickly lead to ketosis
- NEB and ketosis occur usually in the first weeks after calving
Ketosis is a metabolic adaptation in which a reduced availability of glucose is compensated by the increased supply of ketone bodies from the lipid metabolism.
Thus, the energy of those tissues (e.g. brain, red blood cells...) which cannot cover their energy needs in a glucose deficiency or can cover them only insufficiently by the cell's own β-oxidation is ensured. 15
Excessive or prolonged ketone metabolism has negative side effects (lack of cellular energy, excessive lipid mobilization, redox damage, impact on immunological reactions, ketoacidosis).
Subclinical or clinical ketosis severely impairs health and performance. 4, 15
Symptoms of ketosis in cattle include
- appetite (down arrow),
- motility of the rumen (down arrow),
- solid consistency of the feces or constipation,
- fruity smelling breath (like acetone) and, in extreme casesneuronal disorders (e.g. apathy, agitation, seizures or blindness). 4, 8
If ketosis develops due to a lack of energy in a healthy animal (e.g. due to fasting or inadequate feed intake capacity during high-performance phases), we refer to this as primary ketosis.
If the ketosis arises as a result of another underlying disease, however, it is called secondary ketosis. 22
Numerous studies and meta-analyses show the connection between ketosis and impaired performance and fertility and health disorders. 18, 24
The last three weeks prior to calving have a critical influence on the metabolic stability and health in the first three weeks after calving. Therefore, feeding, management and health monitoring must be especially accurate during this transition period.
Problem: Negative energy balance p.p. 76
The slowly increasing feed intake p.p. contrasts with the rapidly rising energy output of the udder. A negative energy balance (NEB) develops. In high-performance herds, this may last about 100 days - and even longer in individual animals.