The Importance of the Transition Period: Benefits of Getting it Right

For a dairy cow, what happens in the three weeks prior to calving to the three weeks after calving is crucial to her success. The calendar year is 365 days and the gestation length of a cow averages 282 days. Therefore, we are expecting cows to calve, peak in milk production and conceive, all in 82 days.

Unfortunately, despite all attempts, there are still too many NZ cows that succumb to life threatening and production limiting conditions during this time and the fact remains that over 50% of reactive animal health spend is during the transition period.

One of the most important conditions to avoid in cows is milk fever (MF). This is because MF is considered a ‘gateway disease,’ which increases the risk to many other significant conditions. It is worth noting that there are two types of MF: clinical MF (‘drunk’/wobbly/down cows) and subclinical MF (the not so obvious form of the condition). Subclinical MF occurs when the cow appears to be standing and acting normally BUT her gut and uterus have stopped working due to low blood calcium levels. This condition is associated with increased calving issues, uterine prolapse, retained placenta, mastitis, displaced and twisted guts, suboptimal production and suboptimal reproductive performance. Even white blood cells responsible for fighting bacterial infection stop working as well!

Based on this, as vets and farmers, we must do everything we can to minimise the chance of cows developing clinical and subclinical MF around calving.

Areas to focus on to minimise MF

• Transition diets- ensuring energy, calcium, magnesium are optimal

• DCAD- in basic terms, avoiding grass and feeds high in potassium at calving

• Management of springer cows- not too much grass while still providing sufficient room for cows to rest

• Management of fresh cows- including considering OAD in the colostrum mob and provision of additional calcium such as

  • Limeflour post calving over pregrazed pastures

  • Metabolic bags under the skin of high-risk cows

  • Drenching with starter drenches, eg. Starter plus

  • Bolusing with ‘Transition boluses’

The take home messages are

• Minimising clinical and subclinical MF must be a focus for any farmer wanting to achieve top results for their herd and business

• Not all issues are obvious; blood tests at calving can help identify issues before they create too much damage

• FVM veterinarians are highly experienced and well placed to offer sound advice to help improve any potential issues through practical recommendations that work