Body condition score at calving is a major driver of both herd reproductive performance and production.  Having a large proportion of your herd (more than 15%) below a body condition score of 5.0 at calving will lead to expensive impacts in both these areas.  The updated table below has recently been released by DairyNZ and gives days required for cows to reach target body condition scores at calving, given their current BCS.  For example a 4 year old cow which is a BCS of 4.0 on the 28^th of April and is calving on the 10^th August needs to be dried off on the 1^st May if she is to get to a BCS of 5.0 by calving.  This is assuming that she will be fed feed with the same quality as autumn pasture.  Under South Otago conditions the column labelled “Autumn Pasture” provides a more realistic time frame as opposed to the column next to it, as this table has been released for the whole of NZ and therefore does not account for our cold wet winters when the cows can be belly deep in energy sapping mud.  Under our crop wintering conditions the average quality of the feed we use to winter cows is probably similar to autumn pasture if you include the nutritional value of the Brassica, balage and straw/hay in the ration.

Farmers often fall into the trap of trying to hit a milk production target and end up milking their cows for too long into the winter which negatively impacts on next season.  If you want to tighten up your calving spread, reduce your reliance on inductions and produce more milk next season you should be looking hard at the individual BCS of the cows in your herd.  Clutha Vets have a number of trained staff members who are competent at body condition scoring and can provide you with an unbiased assessment of your herds overall BCS as well as identifying any cows that are below the target you set for drying off early.  If you have any questions about herd BCS then please contact one of the large animal team at the clinic.