Calcium deficiency has major impact on herd health

A calcium deficiency among your herd is a common but underestimated health challenge. With calcium deficiency around calving, a cow is unable to use calcium from her bones quickly enough to get and maintain blood calcium levels. We would like to tell you more about the occurrence and avoidance of calcium deficiencies.

Because of the milk production and milk yield peak expected after calving, the calcium requirement rises sharply. Not only because of production, but also because of colostrum, which excretes twice as much calcium (2.4 grams per litre) as normal milk (1.2 grams per litre). Cows and heifers that produce a lot of colostrum before calving therefore also lose a lot of calcium. A consequence of this is that appetite drops and, as a result, they fall into a non-optimal energy balance. This is because the cow’s body then has to adapt too quickly to the greatly increased need for calcium.

On average, as much as five to six per cent of the herd on a dairy farm suffers from calcium deficiencies. Calcium deficiency not only reduces milk yield, but also affects fertility. And in the worst case, it can cause mortality. High-yielding and older calf cows are particularly affected by calcium deficiency. To optimize animal health and prevent calcium deficiency in dairy cattle, an adequate dry matter ration and the right supply of calcium, phosphorus, magnesium and vitamin D are crucial.  

When does calcium deficiency occur?

A calcium deficiency usually occurs within 48 hours of calving. However, the calcium deficiency may also have developed just before or during calving. This can often be seen at calving itself, when calving proceeds very slowly or stops. This poses a great risk to both cow and calf. As many as 50% of cows and 25% of heifers and second-year cows show dormant calcium deficiency. In this group, therefore, challenges about calcium deficiency and all its consequences lurk.

A cow that has a serious calcium deficiency can be recognized by low appetite and low activity. Her ears are also often cold. Also, the calcium deficiency in the blood causes the skeletal muscles to stop working properly. As a result, your cow can no longer get up properly, for example. Other muscles are also affected by the calcium deficiency. This can have far-reaching consequences for calving and when closing the cervix, but also affects all other organs such as the heart and rumen. Statistically, more than 5% of cows die from calcium deficiency.

What causes calcium deficiency?

Calcium is present in both the blood and bones of a cow. With increasing milk yield, there is also an increasing calcium requirement. When a cow suddenly needs this amount, she starts using the calcium supply from the blood. This calcium supply in the blood is later replenished from the bones, kidneys and intestines. However, this process can take some time. Thus, because of the delay, calcium deficiency can still occur in the body (Bosseart, 2009).   

What is often forgotten, but should not be underestimated, is that when calcium deficiency starts, cows also regularly have non-optimal rumen function. The rumen contractions stop, which also stops feed breakdown. In this way, the cow ends up in a vicious circle which has a negative impact on the health of your cows. They then often cannot even absorb calcium from the feed at all and calcium deficiency is the result.

Which hormones play a role in calcium?

Several hormones are associated with the release of calcium. Para-thyroid hormone (PTH) reduces the amount of calcium excreted through a cow’s urine. In addition, PTH causes calcium to be withdrawn from the intestines. It does this by activating vitamin D. However, this process does not start until one to two days after calving. Besides vitamin D, magnesium is also very important because this mineral releases PTH. If a cow is deficient in magnesium, PTH cannot be activated and therefore less calcium can be withdrawn from the body. 

Potassium levels also play an important role. Indeed, if the potassium content in a ration is too high, magnesium can again be poorly absorbed. In addition, 80% of cows that remain flat after calving also have a phosphorus deficiency in their blood (Goff et al, 2014). 

Improve the health of your herd around calving

As is well known by now, there are plenty of challenges around calving. To prevent any calcium deficiency, it is important that your herd gets enough calcium, magnesium and phosphorus. AHV Milk Start Paste is a mineral supplement for lactating dairy cows. Developed for dairy farmers according to the latest insights with easily absorbable calcium.

It gives your cows a calcium boost and also contains magnesium, phosphorus and active Vitamin D3. Vitamin D3 promotes the absorption of calcium and phosphorus from the bones and intestines, improving your cow’s metabolism and calcium metabolism. 

The advice from AHV Specialists is to administer AHV Milk Start Bolus about 24 hours before calving. This way you ensure that the cow has the right substances to meet its needs at the time of calving. AHV Milk Start Paste is recommended to be administered immediately after calving, so that your cow is quickly supplied with sufficient magnesium, calcium and phosphorus. In addition, the paste gives the cow an energy boost, making her feel the need to feed faster and restarting the process. This way, you optimize health at the start of lactation.