When it comes to managing a profitable dairy herd, you have to place a high priority on mobility. If your cows are suffering from pain and discomfort when they try to walk, every other area from reproduction, to nutrition and milk production will be negatively affected. Unfortunately, we often don’t identify the problem until it is so far along that treatment costs are high and recovery rates are low.
Step by Step: There are three main areas to address
- Observation and Detection
- Environment and Genetics
- Treatment and Medication
OBSERVATION AND DETECTION:
Of course, the goal is to reduce lameness to a zero percent occurrence. Even if everyone observing the herd strives for this objective, it is a difficult job, especially if the animal to observer ratio is high.
- Numerical Rating Scores (NRS) Work
Studies on gait scoring or locomotion scoring are available to make assessment easier. Some research studies have gone a step further incorporating weight displacement analysis. The use of a weight scale to read the weight displacement from one leg to another supports the observation that lame cows in standing position will remove weight on their injured leg by transferring body weight to the opposite (contralateral) leg. These studies are scored from video recordings, some of which are available on the Internet and are quite helpful in identifying and understanding observable characteristics of lameness. Researchers recorded gait scores and weight transfer before and after they injected a local anaesthetic (lidocaine) to healthy and lame lactating dairy cows. Results showed that 92% of cows with sole ulcers were correctly identified. For the day-to-day dairy operator, it will still come down to personal observation which is not perfectly accurate. In the always evolving age of technology, it probably won’t be long until an automated system is available to measure the weight distribution on each hoof, while cattle are in a holding area or milking stall.
- Administering anesthetic
Lame cows treated with anesthetic demonstrated less weight transfer to healthy limbs, as indicated by both gait scoring and a scale that measured weight borne by each limb. It was found that, before injection of the anaesthetic, lame cows were transferring more weight from the injured leg to the contralateral leg, and they also had a higher gait score than healthy cows. After injection of the anaesthetic, the gait score of lame cows decreased and the animals reduced the weight transfer from the injured leg to the contralateral leg. The study concludes that the two methods of detecting lameness have some degree of validity.
- Lame Cows Stand Apart in Other Ways Too
When an animal has sore feet, it affects other areas of their movement and how they move through their environment. One study noted four non-foot areas that were present when there was lameness or other foot problem: 3.8% had neck lesions, 3% had broken tails, 23% had dirty hind limbs and 4.6% had dirty udders.
- Future studies
Work is being done with infrared thermography and visual examination of dairy cows in different stages of lactation to see the effects of lameness on milk production.
CAUSES: ENVIRONMENT AND GENETICS:
Once, the lameness problem has been identified, we start looking to discover what has caused it. It comes down to two choices, environment and genetics.
Research points to three helpful conclusions:
- Cows housed in tie stalls on rubber mats spend more time lying down and have fewer hock injuries than those housed on concrete.
- Softer, higher-friction flooring improves the gait of cows with and without sole ulcers.
- Wet conditions. Exposure to moist surfaces results in softer claws and cows with softer claws are at greater risk for lameness.
- By far the area with the most environmental impact is tie-stall design. Some dairy cows spend most of their days confined in tie-stalls. Tie stall design can, therefore, affect animal health, welfare, productivity and longevity. Studies are available that can provide the pros and cons of stall length, width, tie-chain length and tie rail height.
Genetics of Locomotion
We have all heard cattle classifiers and show judges point out that locomotion is a key point in identifying exceptional animals. “Moving on a great set of feet and legs” is highly desirable. Cows with a higher feet and legs score, steeper foot angle and somewhat straighter legs have genetically better locomotion. We all think we know what great legs look like, but the inheritance and genetics of proper foot structure is an area that requires scientific research.
TREATMENT AND MEDICATION
At the simplest level, although not always achievable, lame cows benefit from spending even short periods of time on pasture. Relative to the cows housed indoors, cows on pasture improved by a full gait score (i.e. from 3 to 2) over the 5 week treatment period. Two specific elements of gait, tracking up and reluctance to bear weight evenly on all 4 hooves, also improved. There was no change in two other specific gait elements (head bob, back arch). Cows on pasture also spent less time lying down than did cows kept indoors. The study concluded that lame cows benefit from spending even less than 3 weeks on pasture.
Cows were scored after administered pain relief medication (ketoprofen) to cows exhibiting gait impairment. Saline was administered to lame control cows. Cows were scored before, during and after treatment. Numerical Rating Scores improved in response to ketoprofen dose, with the greatest improvement occurring at the highest dose (3 mg per kg of body weight). However, even NRS improved by only 0.25 suggesting that more potent drugs are required to treat this pain or that much variation in cow gait is due to factors other than pain.
THE BULLVINE BOTTOM LINE
You can`t fix what you don`t see. Use your eyes. It is crucial that you use every observable technique at your disposal to identify animals that are having foot problems and, it is even more crucial that you do it sooner rather than later. Keep records. This is one area that sets apart the winners from those who also-ran, or more correctly, those who also-limp.