A look at how seasonal block calving can benefit your business

In the next blog post, we will look at how to achieve having more days in milk by managing a tight calving block.

In the UK, 81% of dairy farmers identify their herds as All Year Round (AYR) calving1 despite block calving shown to be more cost beneficial for some enterprises. For those remaining 19% of farms which are block calving, 42% are autumn calving, 21% spring calving and 37% in spring and autumn.

Evidence shows spring block calving herds can produce milk for lower input costs than an AYR herd, saving around 2.1-2.4 pence per litre (ppL)1.

In autumn blocking calving herds, higher costs associated with feed and housing are offset by higher yields and a better price due to seasonality. For autumn block calving this equates to cost savings between 1.1–1.3ppl1.

So, why are the majority of farmers opting for AYR calving? The answer could be down to mindset, management capability, limitation of physical assets, or to satisfy a milk contract or market that is willing to pay a premium. In some cases, it may not be a conscious decision but one that has been born out of the challenges of managing a tight calving interval. In this situation, users may benefit from the efficiencies and focus of a block calving system but require extra support in achieving and maintaining this.

It is important that whatever system farmers use, they are doing this as a conscious decision based on what is best for their enterprise. This will include considerations such as space to house animals and ability to look after young stock all at once but only for a short amount of time, as well as other building and managemental factors. The Agriculture and Horticulture Development Board (AHDB) has developed a milk price calculator to help farmers decide what system will yield them the greatest returns. http://dairy.ahdb.org.uk/market-information/milk-price-calculator/#.W4VRaehKiUk


Block calving is defined as having all cows and heifers calving within a 12-week window, with the cows getting back in calf, hitting peak milk yield and dried off all together.

The aim of block calving is to do one thing at a time to a high standard with cost and labour efficiency, this includes calving down, heat detection, drying off amongst other things.

AHDB’s Milk Price Calculator shows various financial pros and cons from block calving including:

  • Seasonality payments mean typical autumn block calvers achieve a slightly higher price from standard manufacturing contracts than AYR
  • Spring block calving herds typically receive 1ppl less than AYR herds on manufacturing contracts
  • Both spring and autumn block calving herds typically achieve lower prices than AYR supplying the liquid market

Asides from the already discussed financial benefits there are additional advantages such as:

  • Typical overall labour saving
  • Focussed seasonal management
  • Break in the regime each year
  • Dedicated and predictable (planned) timings for doing individual jobs and tasks e.g. drying off
  • Easier nutrition management for stage of lactation
  • Milking herd run as one unit rather than separate groups
  • Simplified heifer rearing with one heifer group
  • Short intensive use of vet and nutrition advisors


Before considering a move to block calving there are various questions farmers need to consider. For example:

  1. Does it fit your milk contract? You will need to speak to your milk buyer and seek help on how switching to block calving will impact your business. AHDB’s Milk Price Calculator can help.
  2. Have you got adequate labour and resource to cover the intense calving period? The aim is to calve 90% of your herd in six weeks and your entire herd in 12 weeks. You have to ask yourself whether this is something you can manage from a time, labour and building space capacity.
  3. Have you the infrastructure to manage more animals? This includes space in farm sheds, cow and calf accommodation, slurry storage, milk tanker capacity and grazing infrastructure.
  4. Is fertility in your herd good enough? With such a tight calving period needed for block calving to be beneficial, you need to assess whether your cows are capable of this. Fertility aids such as heat detection and synchronisation by using CIDR® devices will help with this.

In summary, there are numerous benefits to a block calving system, both financial and labour/management related. However, this system may not suit all enterprises, there are many support resources to help you understand what is best for your individual farm set up. If block calving is the right move for you then taking control of your herds fertility at the critical time is one of the main ways you can maximise your success. We will discuss this in more detail in our next block calving blog.

CIDR contains 1.38 g progesterone: POM-V. For further information, please contact your veterinary surgeon or Zoetis, Walton Oaks, Dorking Road, Walton-on-the-Hill, Tadworth, Surrey, KT20 7NS. Use medicines responsibly (http://www.noah.co.uk/responsible). Always speak to your medicines provider. AH493/18

1 AHDB Delivering a more competitive industry through optimal dairy systems September 2017