11/22/2022:  In the Netherlands, the focus lies on a sustainable dairy herd with a longer working life. That is only possible if cows are kept healthy to an older age. In 2021, GD conducted an in-depth study into the relationship between working life and animal health. When effectively managed, dairy cows can remain healthy, also at an older age.

From monitoring to in-depth studies

In the animal health monitoring for cattle, we routinely collect data from various sources on for example mortality, udder health, use of antibiotics and metabolism. By compiling and analysing the anonymized data, a picture is created of cattle health in the Netherlands. Once every three months, we need to determine whether this information is in keeping with the expectations. What are the causes of any deviations? In-depth studies into trends and developments then provide clarification for policymakers and farmers. In 2020, we saw the herds in general gradually becoming older. Mortality and the somatic cell count also increased slightly. Strangely enough, farms that housed older cattle actually had lower mortality figures. In 2021, GD therefore conducted an in-depth study into the relationship between working life and animal health.

Large differences

The study mutually compared five groups of farms. The group of farms with the highest working life of cows (nearly 7 years) performed better on virtually all health indicators. However, these farms did have a slightly higher use of antibiotics, a higher somatic cell count and more inseminations per cow. Analysis showed that there were no cases of poorer management of udder health. On the contrary. There were actually a greater number of older cows at the farms, who had already suffered udder infections. Cows of the same age at farms with a constantly low working life (4.5 years) had poorer udder health on average. However, these farms used less antibiotics. They also undertook fewer inseminations per cow. Cows with health or fertility problems are possibly disposed of sooner there.

The search for a balance

The sector requires more sustainable farming, and in turn that requires older cows. Working life and animal health should be seen as a combined whole. Simply managing based on the somatic cell count or use of antibiotics will not suffice. We want healthy animals, with trouble-free gestation, and limited use of antibiotics. While it is a challenge to achieve all these factors simultaneously, it is not impossible. By quantifying the tension between working life and use of antibiotics, this study contributes to well-founded decisions at the policy and farm levels. Subsequent studies should gather knowledge on the management of farms with a long working life.

Data analysis for a responsible working life

Bregje van Erve: process manager at Duurzame Zuivelketen/ZuivelNL

“The dairy sector wants to take a responsible approach throughout the chain. Customers for our dairy products require us to work on animal health and the animal welfare of our dairy cows. And that we do so visibly. One of the objectives within the Sustainable Dairy Chain is to extend the working life of dairy cows. Cows who grow older healthier require less antibiotics and can contribute to other sustainability objectives such as reducing greenhouse gas emissions. That is good for both cows and the dairy farmer, and is appreciated by society.

It is important to have good insight into the developments in animal health and animal welfare. That’s why analysis of data is part of our continuous improvement process. This in-depth study into the working life clearly shows that animal management is one of the determining factors. The early life of young calves can be particularly decisive. A longer working life can go hand-in-hand with limited use of antibiotics, as proven in practice.

The data is now showing that the working life of Dutch dairy herds is increasing. While the indicators are generally good, they need to be verified in practice from time to time. Is an indicator still fitting? In the Dutch dairy farming sector, we have been working at restricting the use of veterinary medication for some time, for example. The use of antibiotics in dairy farming is now at such a low level that the Netherlands Veterinary Medicines Institute (SDa) refers to it as acceptable use. We concur with this, because there must always be the possibility of treating sick animals.

We now need to look at how farm management can result in a responsible further increase of the working life. Thanks to data analysis, we recognise the trends and developments in for example cattle mortality, calf mortality, age composition and transition phases. If certain trends change, we discuss that within the Supervisory Committee for Animal Health Monitoring, and then initiate specific follow-up studies. If there are negative trends in the transition period for example, we can carry out extra studies into the underlying causes such as for example the dry period and the initial period following calving. We continuously assess what takes place in the field, in order to be able to react quickly in case of deviations.

The in-depth study into working life confirms that there are various types of farmers, with varying ideas. We noticed a longer working life in the peat moor areas and a somewhat lower average in the northern provinces. This is in keeping with the difference in considerations between the various regions. When it comes to working life, there is a large distribution between individual farms; farmers can learn from each other.”

An integrated approach will certainly increase the working life of dairy cows

Maarten Fokker: bovine veterinarian at De Klomp Dierenartsen

“In my experience, farmers are not really managing their farm based on the age of their cows. The top three reasons for disposal that I encounter, are issues related to fertility, udder health or hoof health. As long as a cow is in good condition and gestates normally, she is retained.

The sensible economic approach can vary greatly per farm. I know of one farm that always has all cows inseminated. They want the cows to produce calves less frequently, but achieve a longer life production. In their philosophy, each calving is a time of risk. They have a calving interval of around 460 days. While not all cows are capable of this, some cows can maintain a flat lactation curve for a long period of time. If they do decline in terms of production but still keep eating in the meantime, they will become overweight and will have problems gestating, or problems when calving. Many farmers will therefore prefer to have their cows gestate on time. However, it would be interesting to look at the option of a longer interim period between calving, and to include factors such as farming and breeding.

In the dialogue with the farmer, the focus is generally not on having cows continue for as long as possible, but rather on the question of today’s production level, whether that is satisfactory and whether it can be improved next year. The most commonly used indicators are short-term ones. If we wish to shift the optimum working life slightly, that will require a new train of thought. It is of course not always ideal to retain many older animals. The animal health costs may increase due to an increase in the use of medication, the effectiveness of treatments may be disappointing and the animal welfare aspect may then also be affected. An integrated approach will certainly increase the working life of dairy cows, but the preconditions must also be in order. As the study has shown, the use of antibiotics increases in older animals. A farmer focusing on a longer working life of his cows must not immediately receive criticism from the Netherlands Veterinary Medicines Institute (SDa) if the daily animal dosage increases. The farm must be assessed as a whole.

An interesting question is the reason behind the regional differences found in the study. Could this be due to a different setup of the farms, the possibility of outdoor grazing, or the housing systems? This is important information that can provide insight into the question of which factors ensure that cows have a longer working life at a farm.”