On Track - Lameness Guidebook
Lameness is a "multifactorial" problem
When a lame cow is examined, occasionally a single factor can be easily identified as the cause of the problem. For example, if a nail is found driven through the sole of a hoof, the cause is obvious, and the treatment straightforward remove the nail, and counter infection.
However, cases of lameness in which a single cause is easily identified are unfortunately rare.
Even in a seemingly straightforward case of footrot, multiple factors may be involved. For example, an excessively wet environment may soften skin and make the foot prone to puncture between the claws. If small, sharp stones are present in the environment, they may lodge between the claws and cause a break in the skin. High numbers of bacteria in the environment during an outbreak may lead to overwhelming contamination of a puncture site, and subsequent infection. Each factor is not the sole cause, but when acting in combination, a simple case of footrot results.
In many other foot disorders, for example, abscess of the sole or white line disease, a large number of factors that increase the risk of an abscess developing may be present.
When a number of factors increase the risk of a disease, the disease is said to be multifactorial.
It is important to recognise the multifactorial nature of lameness in dairy cattle, because:
- focusing resources on one factor may result in little progress, even though that factor is a critical point in control of the disorder. Indeed, a disease situation may deteriorate even though an appropriate action is taken. A belief may develop: that this strategy was a waste of time or money.
- focusing resources on one factor may result in apparent progress, even though that factor is not critical to the development of the disorder. A belief may develop: this factor is "the cure". For example, a trace mineral is added to the diet as other conditions improve, and the trace mineral is subsequently regarded as the key to success.
- a large number of separate factors may need to be addressed for progress to occur, and this task may be beyond current resources of time or money. For example, farm hands may need training, and extensive sections of a track may need repair during a busy time of the year when cash flow is poor.
- progress towards control may be slow. For example, if foot shape is poor due to nutritional imbalances or inherited conformation faults, immediate improvement will not occur.
- some factors may be beyond the ability of management to control. For example, track repair may be impossible in prolonged wet weather.
In order to control lameness, it is important to recognise its multifactorial nature.
Many factors increase the risk of dairy cattle developing lameness:
- adverse changes to cow behaviour,
- poor quality walking surfaces,
- restrictions to ideal cow flow,
- human actions that cause adverse changes to cow behaviour,
- excessive wetness in the environment,
- the build up of bacteria,
- imbalances in nutrition,
- and genetic faults leading to poor conformation.
It is within the power of management to reduce or eliminate many of these risks. These factors are discussed in Guidelines 9 to 16.