The transition period is defined as the four weeks before and the four weeks after calving.
As the cow is adapting from non-lactating to lactating a lot of changes are occurring which affect the cow’s hormones and metabolism.
All metabolic processes are intricately linked. A failure of one metabolic process will inevitably impact on the efficiency of others.
During the transition period, there is a greatly increased risk of disease, with 80% of cow health problems happening within this period.
If there is a shortage of essential nutrients, the cow may be unable to adapt resulting in a range of diseases, including:
- hypocalcaemia and downer cows
- ketosis and fatty liver
- udder oedema
- abomasal displacement
- retained foetal membrane (RFM)/metritis
- poor fertility and poor production.
There is now a substantial body of evidence confirming the transition period represents a brief but critically important period of time in a cow’s life when careful manipulation of diet can impact substantially on subsequent health and productivity.
As a result of an increased understanding of homeostatic processes, the concept of transition feeding has evolved from one focused on only control of milk fever to an integrated nutritional approach that optimises:
- rumen function
- calcium and bone metabolism
- energy metabolism
- protein metabolism
- immune function.
There are four aims of transition cow management. Cows should be managed so as to reduce disruption to the rumen, minimise mineral deficiencies, provide sufficient energy around calving and avoid immune suppression.
If these four aims are addressed during the transition period, and a successful lactation is established, cow health targets should be achieved.
Establishing a successful lactation means much more than delivering a live calf. It also means:
- a cow with a rumen well adapted to higher energy feeds
- almost no clinical cases of milk fever in the herd
- very low incidence of other cow health problems common in the first two weeks after calving
- low mortality rates in the first two weeks
- higher herd fertility
- more productive lactations;
- less labour and stress from time spent on sick cows
- enhanced animal welfare.