Beyond Calcium: Safeguarding your Jersey Cow Against Milk Fever
Jersey cows are 3.06 times more likely to suffer from milk fever compared to their Holstein counterparts. Indeed, while milk fever affects about 4.82% of Holsteins, it spikes to 14.78% among Jerseys1. But why such a marked difference between these two breeds?
Understanding Jersey Cow Vulnerability
One of the primary factors contributing to Jersey cows’ increased vulnerability to milk fever is their higher milk production compared to other breeds. Jersey cows are renowned for their exceptional milk production, often yielding milk with higher butterfat and protein content. However, this high milk output demands a substantial transfer of calcium from the bloodstream to the udder for milk synthesis.
Consequently, Jersey cows experience a more pronounced decline in blood calcium levels during the transition period surrounding calving.
The Dangers of Milk Fever
Milk fever can lead to various symptoms, including muscle weakness, loss of appetite, difficulty in standing or walking, and in severe cases, paralysis. Cows affected by milk fever are at higher risk of developing further secondary health challenges and reproductive issues.
Table 1: The likelihood of secondary health challenges due to clinical milk fever (Lawlor, 2021).

Support your Jersey Cow’s Mineral Requirements
To support your Jersey cows, a proactive approach centred on robust mineral supplementation during the transition phase is crucial.
While calcium is undoubtedly essential, it’s important not to overlook the role of phosphorus in supporting energy metabolism, cell signalling, and enzyme activation, which collectively bolster overall metabolic function.
For the reduction in the risk of milk fever and subclinical hypocalcaemia, AHV Specialists recommend the administration of StartLac. This specially formulated product provides a balanced combination of calcium, phosphorus, and magnesium crucial for meeting cows’ mineral requirements during calving. By promoting muscle contraction and metabolism, StartLac aids in preparing the cow for the demands of lactation.
Immediately after calving, apply 1x StartLac Paste or 2x Tablet (1x tablet at calving and 1x 12-24 hours later).
The inclusion of Vitamin D3 in StartLac enhances mineral absorption, ensuring that the essential minerals are rapidly released and readily available for metabolic processes. This comprehensive formulation not only supports muscle contractions and milk production but also promotes overall metabolic health, setting the stage for a successful lactation period.
By providing Jersey cows with AHV StartLac, dairy producers can rest assured that their animals receive optimal mineral coverage. This helps them transition smoothly into lactation and lowers the risk of milk fever and associated metabolic challenges.
AHV StartLac Tablet and StartLac Paste are part of the AHV Transition and Fertility Programme which fully supports the recently calved cow and ensures a positive start to her lactation. If you would like more information on how you can power your herds health and productivity, please fill in the contact form below or contact your local AHV Consultant directly.
Sources
Chiwome, B., Kandiwa, E., Mushonga, B., Sajeni, S. & Habarugira, G., 2017, ‘A study of the incidence of milk fever in Jersey and Holstein cows at a dairy farm in Beatrice, Zimbabwe’, Journal of the South African Veterinary Association 88(0), a1457.
Lawlor, J., ‘The latest thinking and practices in milk fever mitigation’ Veterinary Ireland Journal, 11.3, (2021),178-12.
Get in touch!
Would you like to be visited by an advisor to discuss the health challenges on your farm together? Our AHV Specialist will be happy to visit you to jointly assess the health of your cows and come up with appropriate cow-specific advice.
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