How cows are managed during the transition period (4 weeks either side of calving) has a major influence on milk production and fertility in the following lactation. In practice in New Zealand, there are 3 key stages of management which help to achieve good transition.
· Management of ‘far off’ dry cows to ensure body condition score (BCS) of 5 (and 5.5 for heifers and 2nd calvers)
by 3 weeks pre calving
· Management of the springer mob (cows up to 3 weeks pre-calving) to achieve good rumen adaptation, health and feed efficiency, and to minimise metabolic and infectious diseases
· Management of the colostrum mob to encourage increased feed intake
Body condition
· Dry cows off around 60 days before calving at BCS 5 (or 5.5 for heifers) and feed a maintenance diet through the ‘far off’ dry period
· Where this is not achievable, work out how much weight needs to be gained to reach BCS 5 and how much time is needed to achieve this, to determine dry off date
· No weight gain should be expected in the first 1-2 weeks after dry off or the last 3 weeks before calving
· Make sure cows do not get too fat, particularly later calvers
Springer mob
· The diet for the springer cows should have sufficient energy and protein for maintenance plus late pregnancy
· Include components of the milking cow ration to help the rumen adapt
· Rumen microbes take 7-10 days to adapt to a change in diet but rumen papillae (the folds on the inside of the rumen wall that increase surface area for nutrient absorption) can take 3-6 weeks to fully respond
· Starchy feeds and effective fibre are beneficial for papillae growth and rumen function
· All feeds must be clean and palatable - no spoilt or mouldy feed and no butyric silage
· Check the Dietary Cation Anion Balance (DCAB) of the diet and add anionic salts where needed (don’t hesitate to seek qualified advice if unsure)
· Feed no calcium (except under guidance), plenty of magnesium and limited salt
· Feed a high quality trace mineral supplement to help immunity
Heifers
· Introduce first calving heifers to the springer mob in plenty of time to allow them to adapt
· Even if feed is short, don’t leave them away until the last minute
· Ensure sufficient trough space and time if using a feed pad
Colostrum mob
· A starter drench (usually a blend of molasses, mono propylene glycol, protected fat and minerals) at calving can reduce the risk of metabolic issues and encourage feed intake
· If it is not practical to drench all cows at calving, focus on at risk cows (eg milk fever history, twins, older cows, difficult calving, highest yielders)
· Feed the milkers’ ration, with extra limeflour where practical
· Feed the cleanest, freshest, best feeds
Cow feedback
Ask the cows if you have got it right by observing cow condition (be honest and use the guide), grazing behaviour, rumen fill, cud chewing activity and dung consistency. While in the paddock, ensure there is plenty of clean water available.