When a cow goes down with milk fever, it can be a time-consuming and stressful task to get her to recover.
Treatment costs can be high, but the more significant financial impact is in the lost production from both clinical cases (the ones we can see) and sub-clinical cases (the ones that don’t show any signs or symptoms).
Each cow that is treated for milk fever there will be 10-15 subclinical cases. Even cows with subclinical milk fever have around a 7% drop in production for the season. For the average herd this equates to around $4,500 production loss per case of clinical milk fever.
Milk fever causes cows to go “down” because they cannot contract smooth muscle. This occurs due to low blood calcium levels, essential for muscle contraction. The muscles cannot function properly without adequate calcium, leading to the cow’s inability to stand or perform other critical muscular actions (including rumen contractions). This inability increases the risk of several complications:
- Difficult calvings: the cow cannot contract the smooth muscle to push the calf out
- Retained foetal membranes: the cow cannot contract smooth muscle to push the placenta out
- Increased risk of mastitis: the cow cannot contract the teat sphincter, meaning more chance of environmental pathogens entering the teat canal.
Preventing milk fever is also vital for farm sustainability. Healthier cows have higher milk yields, reducing the need for additional resources and replacement animals. This efficiency minimises waste and lowers greenhouse gas emissions, directly supporting a reduction in emissions.
Several factors influence milk fever, including energy, protein, magnesium, calcium, phosphorus, DCAD (dietary cation-anion difference) and vitamin D. Calcium and magnesium are particularly critical, as they directly affect muscle function and blood calcium levels.
Managing DCAD is very difficult with a pasture dominant diet, but can be a powerful tool for farmers with the ability to fine tune their cows' diet. It influences the cow's ability to mobilise calcium reserves before calving. Balancing these nutrients requires careful formulation of the springer diet to prevent deficiencies or imbalances.
In addition to proper nutritional support like Nutritech’s NutriMin® Springer Cow Balancer range, other effective strategies for preventing milk fever include monitoring and adjusting the springer diet, ensuring appropriate calcium and magnesium levels, and managing DCAD to support calcium mobilization before calving. This free technical support has helped many New Zealand farms significantly reduce milk fever incidence.
For more information on preventing milk fever in your herd, talk to your local Technical Sales Representative or visit your Farm Source store.