Dr Alex Bach discusses the indicators of a healthy and productive life for dairy cows, stressing the importance of making decisions based on data rather than gut feelings.
According to Dr Bach, managing a dairy herd requires taking decisions objectively based on the wealth of data available nowadays. He argues that we struggle to extract information from data since there is so much of it, which makes it difficult to manage herds by looking in the rear mirror. Instead, we should start using data to look ahead.Longevity is one of the key indicators of a healthy and productive life for dairy cows. It means that cows are healthy, making an efficient use of resources and good for the environment and public opinion.
It can be achieved with effective heifer rearing and management, or by giving cows a second chance and simply extending their lactation. On the face of it, extending lactation may produce more milk over a longer period, but shorter lactations can produce more profit per day.
Key Performance Indicators (KPIs)
KPIs, such as days open, DIM, culling rate, rolling herd average, and calving interval, are commonly used measures but don’t offer you a straight answer to help identify issues. Whereas KPIs such as SCC, conception rate, days to 1st service, preg rate, income over feed costs, % cows pregnant, and % cows dry, pinpoint a specific problem or solution.According to Dr Bach, focusing on economics is crucial. He argues that people seldom ask what feed efficiency is, despite investing in their animals. Income over feed cost should be the focus, rather than just milk production, which gives a biased picture of reality. More milk does not always mean more money.
If you are going to make decisions based on data, there are two essential concepts to keep in mind. Firstly, distribution, which refers to the shape of the data. Most farm data measures are skewed left or right due to outliers, so if you make decisions based on the average rather than the median, it could be wrong for most of the herd.
Therefore, it is crucial to look at the median and not the average, which most software gives you. Secondly, lag, which refers to the time it takes for decisions to take effect. For example, if the calving interval is 380 days in 2022 and 420 days in 2023, we may think there is a problem. However, the reason why it rose in 2023 is due to decisions taken in 2022, which we can do nothing about.
Data also needs to be reliable. The KPIs that most people ask on the farm are about disease incidence, such as milk fever, retained placenta, ketosis, mastitis, culling rate after fresh, treatment costs, and the number of treatments. All you are doing is taking a picture.
Dr Bach explains that the most important measures are stocking density, DM intake, ration energy, protein levels, comfort level, pen dynamics, and dry period length. If you take care of these, then they manage the other measures until they do not become a problem.
Formulating rations
The single biggest cost on farm is feed (~55%), followed by replacements, so a small decrease can have a huge impact on profits. The impact from other areas, such as herd health is much harder to achieve. He recommends involving your nutritionist before buying feed, not after. Look at ingredients on a nutrient cost basis and do not be constrained by KPIs you cannot measure.Formulating rations based on the kilograms of milk produced by each cow is a rule of thumb used by nutritionists, but it's important to ensure that the ration covers the needs of 70% of the cows to avoid over or underfeeding. Overfeeding can result in cows becoming overweight, leading to a host of issues in the next lactation, while underfeeding can put them in a negative energy balance. Getting the balance right can optimize income over feed cost, and therefore your profit.
Monitoring the mixing of the diet is also crucial, as deviation in mixing can result in imbalanced nutrient supply and lower milk production. This applies to all components of the ration, including grain, silage, and protein. Ensuring that cows are fed to meet their nutrient requirements, and reformulating the diet when intake changes, can help avoid over or underfeeding and reduce costs while keeping cows healthy.
For larger groups of cows that require more than one total mixed ration (TMR), there is an opportunity to optimize profits and cow health by creating different rations for different groups.
Cows producing different levels of milk have different energy requirements, so a ration that meets the needs of a higher group may not be optimal for those producing less milk. Although nutritionists may say not to worry, as the lower group will only consume what they need, research shows that they can extract more energy from the same ration. Fear of losing milk when moving cows from one group to another should be set aside, since income over feed cost should be your main focus.
Setting up heifers for a long and productive life, recognizing them as the future of dairy herds, should not be underestimated. This requires careful management and monitoring to develop into highly productive cows.
Indicators to optimize heifer success
Dr Bach’s two critical indicators to optimize heifer success and enhance productivity, while reducing rearing costs, are rearing efficiency and heifer effectiveness.The former evaluates the rearing process by ensuring that a high percentage of heifers born alive calve at or below the target age, indicating a well-managed process. The latter measures good rearing management and longevity by calculating the percentage of heifers born alive that calve at or below the target age and complete three lactations. If you do a good job with heifers, they’ll stay with you for a long time.
Since calves and heifers are the future of dairy herds, they need careful management to develop into highly productive cows. Understanding the key areas to focus on is a good place and ensures farmers can optimize profits, maintain a healthy herd, and ensure a profitable and sustainable dairy farming business.
Another important KPI is colostrum quality. Pivotal for the development of the intestine and the absorption of nutrients and IgGs, colostrum is rich in hormones and growth factors.
However, Dr. Bach views quality in a different way. Studies from both the 1980s and 90s show that the level of Serum IgGs, which pass immunity onto the calf, are affected by the dry cow ration. If the dam had low protein in the diet, despite the colostrum quality appearing good, the calves didn’t absorb the IgGs.
Research also shows that growth in the first 60 days before weaning is positively correlated with reproduction in the first lactation, which in turn links to longevity. However, post weaning growth has a greater impact on future milk production than the pre-weaning period. This phase is a golden opportunity for profit because these calves are super-efficient and achieving 1.2kg daily liveweight gain is desirable to ensure high productivity in the future with relatively low investments during the rearing process.
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Dairy calf management
