Management for Dry Cow Systems
At farm-level, management can be an issue when implementing a correct dry cow system. Seasonal calving and compact calving are ideal, but not without flaws. In a spring calving system, the blueprint is to have 90% of the herd calving in six weeks. The herd goes completely dry around Christmas week and are all going to get around 60 days dry. This does not happen in most cases, with the average six-week calving at 68%. If the herd is all dried off together, then there will be some cows getting up to 100 days dry. These are the cows which will become over-conditioned and have issues when calving.
Best practice should always be followed where possible and always bear in mind that changes made in the dry period can have a knock-on effect throughout the lactation. Group changes can have a negative impact on dry matter intake. Dry cows should be moved to the calving box no closer than 14 days pre-calving (where possible, as this would require a large amount of space, due to the compact calving system). If movement is required immediately, then pre-calving as late as possible (water bag, feet showing) is the correct procedure.
Dry cows need one cubicle/cow and one feed space and 90% of a stocking rate three weeks pre-calving. A feed space would be considered at around two feet per cow, so 100 dry cows would need 200 feet of feed space. This often seems to be an oversight on farms when deciding how many cows they can house.
Clean water should always be available for dry cows. A rough guideline of five centimetres of trough length should be available. Cleaning troughs is essential, as faecal matter will build up. This should be done weekly.
If cows are at grass then, preferably, they are housed for a month pre-calving and are stocked at 25 cows/ha and given a dry cow diet including minerals. There should be very little grass on this paddock and dry cows should not be used to clean up after milkers.
Management of dry cow feed is important. Pit face and forages used should be monitored carefully for moulds. Moulds can cause many issues in dry cows that might not come to the surface until post-calving, such as abortions or metritis. Mouldy silage should not be fed, and if there is a suspicion of mould, a mycotoxin binder, such as Mycosorb A+®, should be used.
Where there are no feed troughs, feed should be pushed in four to five times per day. Weekly cleaning of feed troughs is required, as feed will build up and become mouldy, which will depress intakes. If feeding a TMR to dry cows feed troughs does not guarantee intakes, there can often be sorting which is not observed. If feeding for two days, heating can occur.