Why do we see increased incidences in lameness around mating?

Why do we seem to see an increase in lameness around mating time?

A common thought is that at mating time you have cows riding each other and putting more weight on the hooves of the cow being ridden which causes damage to the hooves – especially when the cow is standing on a stone at that point in time. Whilst that sounds plausible let’s think it through. Cows are not just riding each other at mating time.

Cows starting to come in heat soon after calving so there is already riding activity going on well before mating and yet it doesn’t seem to cause lameness before mating time. Riding each other is a normal natural behaviour and therefore it is reasonable to conclude that cow’s hooves are designed to withstand this pressure. So, let’s look at the bigger picture of what is going on then. Clearly something is different for the cows at mating time compared to the time beforehand. It could be a difference in diet as supplements are reduced or removed due to improved grass growth around this time. Or, is it more heat stress? These are possibilities but I think that it may have more to do with the unique stress on the cows created by the AI process. Think about how life is different for a cow around mating time.

Firstly, somebody is standing on a platform behind the cows at milking time to check tail paint. This is a normal farming practise and very relaxed from a human point of view but look at it from the cow’s perspective. Many cows put their heads up and are keeping an eye on the person standing there. Usually, when a cow sees a person, something is going to happen to them, so their fight/flight response is activated, and they are on high alert. Next you have around 5% of the herd drafted out of the herd back onto the yard. That is a big change in routine for those cows, or the cows may go into a paddock before the AI technician comes but sometime in the morning the cows are taken out of the paddock and something is going to happen to them again. The next day someone is standing on that platform again. The cows don’t know why but go back on to high alert.

You know the feeling when you drive along on the road and suddenly you have a police car driving behind you? You check your speed; you try to remember if you are up to date with WOF and Rego. Even if you know there is nothing you have done wrong you do have this uneasy feeling (high alert) until the police turns off or stops on the side of the road. If you are tuned in well enough with the cows you can tell that they are not totally at ease with the changes around mating time. One more issue to bear in mind is that at mating time there are extra jobs that need to be done during milking and therefore milking will take longer and as a consequence there is even less time for the cow to spend in the paddock, thus resting time is reduced.

I am quite happy to talk to you about some of these issues. I am also keen to look at some of the data that comes from cow monitoring systems, so would love to hear from any farmers using one of these systems. Please feel free to contact me at info@dhi.ac.nz. I would also like to take this opportunity to wish you all a very Merry Christmas and Happy New Year.