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Detecting lame cows: Any time and all the time

Karin Orsel for Progressive Dairyman Published on 14 May 2018

Defining the ‘lame cow’

Lameness is a clinical sign due to an injury or disease of the foot or leg. In a study the Calgary Lameness Research Team performed across Canada in 2011, on average 20 percent of dairy cows housed in freestall barns walked lame, with a range of 0 to 69 percent.

We attributed the wide variety to differences in facilities and farm management.

Remarkably, estimates of lame cows averaged 20 percent for researchers, but when dairy producers were asked to approximate the lameness level in their herds, they said only 9 percent of their cows were lame. One of the most important reasons for this difference is likely the definition of a “lame cow” and a lack of producer understanding of what is truly considered “lame.”

These are the clinical signs associated with lameness:

  • Changes in gait (asymmetry, lateral movement, irregular stepping, reduced tracking)

  • Changes in posture or body movement patterns (including arched back)

  • Changes in weight distribution patterns (limping, head bobbing)

  • Changes in behaviour (reluctance to move, reduced feeding)

  • Joint stiffness

Many scoring systems have been developed to define and identify a cow as walking lame, with the 1-through-5 scoring system promoted by Zinpro and the University of British Columbia among the most commonly used. The proAction initiative has simplified this scoring method for use in lameness evaluation (Table 1).

Gait scoring system for dairy cows

ProAction looks for the presence or absence of an obvious limp (score 4/5), and this results in lower lameness prevalence estimates compared to the 1-through-5 scale used in research where any cow walking with a limp is scored as a 3, 4 or 5.

Which cow is most likely to become lame?

With producers having limited time, it is helpful to know which cows are more likely to become lame and focus on identifying and managing lameness in cows at greatest risk.

Most research agrees four weeks before to four weeks after calving is a risk period for lameness. Although changes in diet were once regarded as the sole reason for this increase in lameness, it is more likely due to thinning of the digital cushion combined with changes in the integrity of the suspensory apparatus of the hoof around calving.

Another potential reason for increased lameness in fresh cows may be related to the stress of moving to a different group, as hierarchy and social status needs to be re-established in the lactating herd. Furthermore, the risk of lameness was higher with increasing parity (Figure 1)

Percentage of lae cows per parity

or in cows with poor body conditions (Figure 2).

Percentage of lame cows per BCS category

Why do we need to detect lame cows?

Detection of lameness has one major goal: to identify cows that would benefit from intervention or treatment. Although some early stage claw lesions may be difficult to detect based on gait, others – for example, sole ulcers – can be prevented at an early stage using anti-inflammatory treatment to prevent severe lameness.

Therefore, early recognition and prompt treatment may indeed lead to a full cure. Conversely, failure to treat may cause a cow to become chronically affected.

How do we detect lame cows?

Lameness can be detected through careful visual inspection. From a distance, look carefully at each cow’s back, shoulder, pelvis and major limb joints. When observing cows in their normal environment, the following aspects need to be considered:

  • Inconsistency (Scoring is not very precise and is open for interpretation.)

  • Alleyway observation is needed to see enough undisturbed strides.

  • Manure on the floor will affect strides.

  • Avoid social interactions between cows, as it changes behaviour.

  • Observer presence and behaviour should not affect cow movement.

  • Cows are prey animals and often conceal lameness signs. Recognizing clinical signs of lameness needs training (and re-training).

  • Impact of udder size: A full or edematous udder will alter a cow’s gait but is not due to lameness.

  • Producers with robotic milking need a strategy around when and how to observe cows in the barn without excessive disturbance.

Producers can use automated equipment to detect lame cows. This equipment is either focused on detecting altered gait directly related to lameness (i.e., number of steps, stride length, etc.) or indirectly (reduced feed intake or milk production).

Combined with altered mobility (i.e., less standing time, fewer steps, slow and shorter strides), lame cattle eat and ruminate significantly less than their counterparts.

Unfortunately, many systems have difficulty correctly identifying the lame cow and, therefore, can aid in lameness detection but not replace visual scoring. Technology can be of particular use for earlier detection of lame cows.

How do we know what causes lameness?

We can use the type of lameness to help identify cause. Two types of lameness that should be differentiated are weight-bearing (supporting limb) and non-weight-bearing (swinging limb) lameness.

Non-weight-bearing lameness is often associated with sole abscess, fracture, critical joint luxation, tendon or ligament injury, nerve injury or arthritis. A confusing category can be the abnormal deviation as a result of fractures and luxations. With claw diseases being most prevalent, we can notice cows don’t want to put weight on the affected claw – more often the outer claw.

Finally, a close inspection of the animal and the claw will help define the cause of lameness. It is very important we get the diagnosis right; the wrong therapy will not allow the cow to recover and likely lead to more chronically lame cows and reduced animal welfare.

Close inspection should start with an observation while walking, with a focus on posture, standing, actions, conformation, gait, foot, limbs, bones, muscles and tendons. It should help us identify the affected leg and locate the lesion (i.e., upper leg or foot).

The second part should focus on observation while the animal is in recumbency or rising. Special attention should be paid to posture, conformation and symmetry. When looking for symmetry, a comparison between left and right is very useful to identify deviations. The final step would include a lift of the foot and careful inspection of claw, including identification of painful areas.

As lameness is a common disorder, a restraint box or chute system is a wise investment. Making it easy to move and handle cows facilitates good diagnosis and proper treatment in a timely manner.

If a restraining option is not available, a simple rope restraint will allow for inspection of the foot. The so-called “beam-hook” method starts with restraining the cow’s head to the opposite side of whichever leg is to be lifted. Roping is shown in Figure 3.

Beam hook rear lef liftingGood records should include information on the following:

  • Onset
  • Duration
  • Signs observed
  • Does the condition affect just one or many animals in the herd?
  • Is the condition mild or severe?
  • Is it static or progressively getting worse?

This information, combined with careful inspection, will ultimately allow for a clear diagnosis and treatment plan.  end mark

This information was presented at the Western Canadian Dairy Seminar, March 2018.

References omitted but are available upon request. Click here to email an editor.

Calgary Lameness Research Team: Herman Barkema, Ed Pajor, Gordon Atkins; graduate students Casey Jacobs, Jesse Schuster, Michelle van Huyssteen; in collaboration with Steve Mason and Laura Solano (Farm Animal Care Associates), Western Canadian Certified Hoof Trimmers Association and specifically trimmers Rob Geier (Casper Trimming) and Elbert Koster (No-Tilt Hoof Trimming).

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