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Monitor the critical points in calf raising

Benjamin Potvin for Progressive Dairy Published on 31 July 2019
An easy place to start monitoring a calf-raising program is by recording average daily gain; use a weigh tape to measure weights at birth and again at 8 weeks old.

Calves are the future of your dairy. We know their health, growth and performance before weaning will have impacts on production, reproduction and longevity later in life.

The calves on your farm are also a major expense. Raising replacements to calving age is the second-highest expense on your farm after feed costs.



Most farms do an excellent job at monitoring their feed quality and costs and how it impacts the performance of their dairy. But how often do you put this same attention to detail into monitoring your second-largest expense: raising replacements?

There is real money on the table when it comes to minimizing disease and maximizing growth. This is why we believe in the importance of monitoring the critical points in calf raising.

It’s quite simple: If you don’t measure it, you can’t monitor it. So what should we measure to evaluate calf-rearing practices?

To answer this, we need to know the major factors that influence calf health and performance, and then look at these indices as a complete picture.

Our veterinary clinic, in collaboration with veterinary colleagues in Alberta and Ontario, have started to measure and monitor what we feel are the critical points in calf raising.


Looking deeper into calf-raising practices and monitoring calf performance have helped our clients spot trends more quickly, monitor protocol adherence and ultimately target areas of improvement that have helped their calf-raising programs succeed. We are excited to share some lessons we have learned from this program.

Lesson 1: Calves do need more milk in winter months

As temperatures began to drop last fall, we saw clear decreases in average daily gain (ADG) from birth to 8 weeks old on almost all farms (Figure 1).

Average daily gain and average monthly temperature

Even in the Fraser Valley, British Columbia, where winters are mild compared to the rest of the country, it is evident management changes are needed during winter months in order to maintain growth rates and double birthweights by weaning.

Calves start to expend more energy to keep warm once temperatures start to dip below 10ºC. We recommend to our farmers to increase milk feeding by 25% when temperatures begin to drop. As well, using straw bedding and calf jackets will reduce heat loss in preweaned calves so they retain more energy for growth.

Lesson 2: Dirty bottles can look like clean bottles

Equipment used for daily milk feeding are hotbeds for bacterial growth. Just like in a parlour with a clean-in-place (CIP) wash problem, poorly cleaned calf-feeding equipment will quickly form biofilms that produce enormous amounts of bacteria.


High bacterial levels in milk can lead to scours, make calves more susceptible to pneumonia and have negative impacts on calf growth rates. These bacteria-producing biofilms are not always visible, nor do they always smell like rotten milk.

You can’t tell how dirty your bottles or buckets are just by looking at and smelling them.

True bacterial levels in milk can be determined by culturing sterile water run through the milk-feeding equipment or can be estimated with a luminometer.

Luminometers are devices that measure ATP, a molecule produced by living organisms. High levels of ATP measured by the luminometer are strongly associated with high levels of bacteria.

Routinely measuring bacterial levels will validate that your cleaning SOPs are working, and SOPs are being followed. Again, if you don’t measure it, it can’t be monitored.

Benchmarking luminometer measures on over 25 farms have helped us identify successful equipment cleaning practices. Sharing these practices with farms that have struggled with maintaining adequate cleaning for calf-feeding equipment has given them tools to change their practices and improve their SOPs.

Lesson 3: Measuring is key when it comes to passive transfer rates

Passive transfer is a quick and simple blood test that measures the number of immune molecules the calf absorbed from colostrum.

As keen producers, you have heard your veterinarian stress the importance of getting adequate amounts of clean colostrum into your calves in a timely manner. But is the program you have in place working? Are your employees correctly following the SOP? How do you know?

Over the last few months, the veterinary clinics involved in this project have measured passive transfer rates on over 1,000 calves during the first week of life. Farms should strive to have more than 90% of calves attain total protein levels of 5.2 grams per decilitre (the value used in this data as a cut-off), which is considered to be the minimal acceptable level of passive transfer needed for calves. New data suggests we should be aiming for total proteins of at least 6 grams per decilitre to best set up calves to thrive.

In Figure 2, you can see some improvements in passive transfer rates as farms have enrolled in a monitoring program, but clearly there is a lot of opportunity for improvement.

Average % of calves on each farm with total protein values ≥ 5.2 g/dL by month enrolled in routine monitoring (across all three veterinary clinics)

At the new recommended level of 6 grams per decilitre, our average farm pass rates would be less than 50%.

Routinely monitoring passive transfer rates will help us address the failure points in colostrum protocols and hold everyone accountable for doing a good job with every calf.

After all, passive transfer rates do matter; see Figure 3 to see how, as passive transfer rates on farm decline, the preweaning calf mortality rate tends to increase.

Passive transfer vs pre-weaning calf mortality

I hope this encourages you to think about how you can monitor your calf-raising program. An easy place to start is by recording ADG; use a weigh tape to measure weights at birth and again at 8 weeks old.

What percentage of your calves are doubling their birthweight in this period? Keeping complete records of calf disease incidences is also an easy and important tool to monitor your calf program.

At your next herd health, ask your veterinarian to measure total proteins on any calves under a week old. Are your calves meeting the 6 grams per decilitre cut-off?

Taking simple steps like these can pinpoint areas of opportunity and help you maximize your future herd’s potential.  end mark

PHOTO: An easy place to start monitoring a calf-raising program is by recording average daily gain; use a weigh tape to measure weights at birth and again at 8 weeks old. Photo provided by Benjamin Potvin.

Author’s acknowledgements: Thank you to Dr. Kristen Edwards, Tavistock Veterinary Services, Ontario; and Drs. Betty-Jo Bradley and Melissa Wallace, Livestock Veterinary Services, Alberta; for sharing their knowledge, experience and data.

Benjamin Potvin is with Agwest Veterinary Group, Abbotsford, British Columbia. Email Benjamin Potvin.