In the first four articles of this series of lameness awareness, I explained why lameness occurs in dairy cows and raised a better understanding of this mysterious topic. From here, the emphasis will be on certain risk factors that increases lameness.
After the good rainy season we had this year, many grazing dairies experienced more lameness than usual. The types of lameness that we found in these situations were thin soles and toe ulcers.
I explained previously that the bovine claw capsule grows at a rate of 5 mm per month. When the hoof trims naturally, the production of 5 mm would have been enough to balance the amount of wear on the hoof capsule, but dairy cows that need to walk up to eight kilometers per day on walkways to and from the milking parlour and the grazing paddocks, wear their soles down at a faster rate.
The moment the wear exceeds the growth, the hoof capsule does not give enough protection to the corium. When the corium becomes bruised and inflamed, it does not produce healthy horn. The unhealthy horn has pores filled with dead blood where anaerobic bacteria grow and a vicious cycle begins in the form of lameness. Furthermore, wet conditions result in claws that are not hard and dry enough to be able to resist the wear.
Walkways that are too rough and stony, or even filled with puddles of mud, will increase the risk of too soft feet and too much wear. Walkways should be rounded or slightly sloped to allow water drainage. The top layer of the walking surface should be fine and compacted. The transition area from gravel to concrete is also a high-risk factor.
Cows that walk at their own pace will be able to position their feet on the best possible place to prevent painful insults. A common mistake would be to herd the cows to the parlour at a speed that is comfortable for a human to walk. Cows walk at a speed of 3,4 kilometers per hour and humans at 6–7 kilometers per hour. Moving too fast behind the cows would result in cows lifting up their heads and not being able to see where they walk.
Guest Writer & Consultant to DairySmid: Jaco de Bruin