“I came to one of your seminars on Understanding Lameness and I have forgotten most of what you said except you claimed each type of lesion has a different set of risk factors.
“After the seminar I started to record what I could see on every lame foot I treated.
“Before Christmas this season nearly every lame cow had a white line injury. I am still getting a lot of white line injury but in the last two months this has changed and now almost half the lame cows have sole injuries causing lameness.”
Because the farm had good records of every lame cow case, and when they had occurred, I knew it would help us work out what had gone wrong.
I visited the farm and did a thorough risk assessment, looking at the tracks and the dairy design, and cow management both on the tracks and during milking.
The answer became clear. In the yard there was an unusual reaction to the movement of the backing gate. You could only see it from looking down on the cows.
As soon as the backing gate was turned on the whole herd reacted and jumped to get away from the gate and the yard pipework.
The cows jammed up against each other with heads up and feet skidding on the concrete. From the pit you couldn’t see this reaction. We found there was an electrical short from the backing gate.
This was a major risk for white line separation and subsequent abscesses. I guessed it had probably been there all year, explaining the number of white line injuries throughout the season.
What about the sole injuries that started to appear in late December? The main risk factors for sole injuries in pasture-based systems are long distances walked, abrasive walking surfaces and gravel on concrete.
On this farm the cows had a fairly long track of 2km to the furthest paddock. Early in the season the farmer was purposefully alternating far and close paddocks each milking to try to keep the average walking distance as short as possible.
However, because of the high number of lame cows early in the season, the lame cow mob (up to 70 cows) was grazing all the close paddocks.
By December the milking herd had to walk about 500 metres to the closest paddock and the average total daily walk was more than 5km.
White line disease.
The second risk factor for sole injuries – poor walking surfaces – happened when heavy rain started in December.
The tracks had been poorly constructed, with a camber that was too steep. The top surface was washed off and the cows forced to walk on exposed volcanic gravels.
The third risk factor for sole injury was steep tracks with poor drainage near the dairy, resulting in gravel being washed and carried on to the concrete holding yard.
Gravel on concrete together, with the pressure in the yard from the stray electricity, further increases the chance of sole injury.
This farmer’s story illustrates how records can help you identify the risk factors for each type of foot condition causing lameness.
