Article Summary: Drying off cows gives lactating cows a rest from producing milk, keeping cases of mastitis under control and ensuring animal wellbeing. The process enables cells in milk-producing glands to regenerate and the cow to build its’ health up before transitioning to pregnancy (the calving period) and its next lactation cycle. You can ultimately choose when you begin drying off your dairy herd, but you need to know what to do when it is time to rest your cows before calving begins.


Just like news of La Nina finally showing signs of abating across the East Coast of Australia and parts of New Zealand in the new year, it’s the news we’ve been waiting for: the drying-off process will soon begin. 

While we won't see much of this over the summer months yet, by April, it is expected that the seemingly neverending wet weather will make way for finer conditions and some easier days ahead for farmers across the eastern seaboard.

In a farm setting, while clearer weather and the drying off of cows mean fewer cattle in the dairy to feed and milk, it’s important not to lose sight of your dry cows over the new year and summer months. The recommended average dry period for a cow is eight weeks long, and it’s important to ensure solid nutritional management so that the transition period (calving) runs smoothly, with the next lactation phase yielding as much milk as possible.

This article looks at the process of drying off your dairy herd and how you can set yourself up for a successful calving season in the new year.

What is Drying Off?

Drying off cows gives lactating cows a rest from producing milk, keeping cases of mastitis under control and ensuring animal wellbeing. It is the stage where a cow rests, repairs and prepares for calving in the spring.

The process enables cells in milk-producing glands to regenerate and the cow to build its’ health up before transitioning to pregnancy (the calving period) and its next lactation cycle. A dry cow will still produce milk, but usually under 5L a day.  

When is The Best Time To Dry Off a Cow?

Firstly, time is on your side. Autumn is an ideal time to complete your set-up to enjoy successful calving, good health and peak lactation. As a cow’s gestation period is around nine months, this will see healthy calves born in spring.

Of course, it’s up to you when you want to calve, so you would adjust the drying off time accordingly. In short, dry off in the condition you wish to calve. In addition to this, it is wise to consider other factors when making your decisions, like your:

  • Financial budget

  • Milking platform feed budget

  • Winter feed budget, and

  • Body Condition Scores (BCS) of your cows before calving (more on that to follow)

Cutting corners and not doing your due diligence will only affect subsequent seasons. For example, if you begin calving too soon before a cow is in peak condition, there are risks to the calf's condition. This loss is transferred through poor production, milking yields, and reproductive performance. 

How Can You Check If A Cow Should Dry Off?

Cows that produce between 5L and 12L of milk per day are ideal for drying off without running risks of clinical mastitis. You can also adopt an early pregnancy testing system to ensure the optimum dry-off period for individuals and peak conditions for calving.

When a cow is producing over 12L of milk per day and due to dry-off, first reduce her food intake. Then continue milking until production reduces to under 12L per day. Then you can add her to your quota and begin drying off using one of the common processes outlined below.

Using Body Condition Scores (BCS) To Determine Dry-Off Readiness

The recommended score for drying off cows is between 4.5 and 5.5 on a 1:8 scale. According to Dairy New Zealand, few cows score in this range at any time. As a farmer, this puts the onus back on you to ensure your stock's optimum health and well-being and set higher standards for the industry as a whole.

What Are Common Methods Used To Dry Off Dairy Cows?

There are two main methods for drying off a cow.

  1. Ceasing Milking Immediately - Then, apply dry cow therapy principles immediately.

  2. Intermittent Milking - Milking once daily during the last week of lactation and beginning dry cow therapy immediately after the last milking.

Follow up both methods immediately with dry cow therapy. This is the management of keeping dry cows healthy through monitoring and optimum nutrition, which we’ll explore further below. Doing this will reduce the prevalence of udder infections, like mastitis, that is more likely to occur if you simply cease milking.

Keeping Dry Cows Healthy Through Nutrition & Management

After working hard all year, it’s natural to want to bring in the new year with your foot off the brakes. However, appropriate nutritional attention and management (aka dry cow therapy) of dry cows will assist with the transition of cows and positively affect your herd’s production efficiency in the next cycle.

  1. Pregnancy Testing

Testing for pregnancy early, up to 16 weeks gestation, allows precise conception and calving date estimates. It also determines the appropriate dry period for the individual.

Early pregnancy testing also allows the identification of empty cows or cows with other issues so that you can take appropriate management steps before they become more serious. For instance, a case of sub-clinical mastitis would require swift treatment, and multiple (twin) pregnancies would require an urgent dry-off to allow for a typically shorter gestation window.

  1. Feed Management

Cows that are underweight or overweight at calving run the risk of problems. They can cycle later and struggle with further pregnancies. Later calving cows are prone to shorter lactations, resulting in a loss of income for each empty day. 

The good news is that you can control these issues by feeding your cows correctly.

Using Body Condition Score in Feed Management

Assessing the Body Condition Score of your cows at dry-off will allow you to adjust their diet accordingly so they are in prime condition for calving. As a rule, we recommend you adjust the weight of dry cows gradually, by no more than 0.5 points, either to prevent them from becoming overweight or metabolising their body fat too quickly. 

Over-conditioned cows mustn't lose condition too fast. Feeding them less dry feed too quickly may result in metabolic problems during calving, impacting milk supply and future reproductive returns.

On the other hand, cows that have lost condition (with a BCS of less than 4.5) need an increased and preferential feeding regime to ensure fat reserves are not metabolised.

What To Feed Dry Cows

Feed your cows good quality food that contains key nutrients, especially long fibre and mineral supplements, like magnesium and trace minerals. These nutritional elements ensure peak condition during the dry period and minimise risks of calving problems, such as:

  • Rapid weight loss

  • Ketosis

  • Milk fever 

  • Retainreasonable, etc.

Cows withhold up to 80% of their total energy and protein supply from fatty acids and microbial protein. It is therefore recommended that you ensure enough microbial activity in their diet, even in a loss of appetite due to pregnancy.

Including magnesium chloride and sulphate in their diet will also help reduce the risk of milk fever post-partum. Vitamin D supplementation is wise to include in the diets of dry cows with a lower pasture intake. 

While all these parts contribute to a healthier group of dry cows, good nutrition is only good if administered in a hygienic setting with good management and ethical handling processes.

  1. Checking all Quarters for Mastitis

Reduce the prevalence of sub-clinical mastitis, an asymptomatic infection and therefore invisible before it leads to the more serious clinical presentation with regular checks on all quarters. Especially important in the days after milking cessation, ensure all quarters are tested and treated together to ensure absolute animal health and well-being and a thorough screening process.

You can administer these screenings in several ways, and you already have a system to help you manage the process. If your herd are suffering from mastitis, you’ll be able to treat it swiftly and ensure your cows are back to optimal health as soon as possible.

While it’s the right time to begin your drying-off process, it can be daunting and potentially costly if unprepared. The good news is you have time and can ultimately choose when you begin, but you need to know what to do when it is time to rest your cows before calving begins.

Pasture.io’s pasture management satellite technology can help you achieve this in conjunction with the above measures. With unlimited data, record keeping, grazing automations and AI that gets to know your farm, you’ll have all the data you need to ensure smooth operations during drying off phases.

You may have questions and require advice on body condition scoring or drying off cows and dry cow therapy. In that case, we advise contacting your herd vet, nutritionist, or the dairy body in your state or territory.

Until we meet again, Happy Drying Off!

- The Dedicated Team of Pasture.io, 2023-02-02