Milk Fever: An Overlooked Threat in High-Producing Dairy Cattle
Kumar Shubham¹*, Vidhu Kumar¹, Aditya Singh¹
¹Animal Nutrition Division, National Dairy Research Institute, Karnal, India
*e-mail: kumar.shubham76320@gmail.com
ABSTRACT: Milk fever is a serious metabolic disorder that typically emerges in high-producing dairy cattle during the calving period. Beyond immediate treatment strategies, nutritional interventions like limiting dietary calcium and increasing phosphorus play a pivotal role in prevention. Balancing dietary cation-anion ratios has emerged as an effective approach to reduce risk. Variables such as breed, age, and number of calvings influence susceptibility, underscoring the need for tailored feeding practices, less-potassium forage, and low-stress environments.
Key words: Periparturient period, serum calcium level, dietary cation anion difference, body condition score, calcium borogluconate, anionic salts.
Introduction:
Milk fever or Hypocalcemia also known as hypocalcemia, typically arises during the transition period around calving. Sudden spikes in calcium demand due to milk production overwhelm the body’s capacity to mobilize or absorb calcium effectively, especially in genetically predisposed or poorly managed cows. Clinical signs range from weakness to collapse, and delayed intervention often results in fatality.
Predisposing factors that may lead to milk fever
- Age:Older cows in their third to fifth lactation are particularly vulnerable due to reduced calcium mobilization efficiency and hormone receptor activity.
- Breed:While Holstein Friesians are often blamed, Jersey cows show greater susceptibility owing to fewer intestinal receptors for active vitamin D. Indian crossbreeds like Gir, Sahiwal, and Murrah buffaloes also show notable incidence.
- Parity:Risk intensifies with each successive lactation, especially after the third.
- Diet: Diets high in sodium and potassium elevate DCAD (Dietary Cation Anion Difference), inducing metabolic alkalosis that hinders calcium mobilization. Over-supplementing calcium during late gestation can render the parathyroid hormone ineffective post-calving, leading to hypocalcemia. Avoid abrupt mineral changes and dietary changes.
- Management Practices:Immediate and full milking post-calving increases calcium demand. High body condition scores and limited Vitamin D exposure exacerbate the issue.
Effects due to low Calcium level
Deficient calcium slows down gastrointestinal motility, raises the risk of abomasal displacement, and depresses feed intake, triggering fat mobilization. It compromises muscle contractions, which can prevent proper teat closure and raise mastitis risk. Severe hypocalcemia impairs mobility and blood clotting.
Stages and symptoms associated with Milk Fever
| Stage | Serum Ca(mg/dl) | Symptoms |
| I – Standing | 6.5–8.0 | Lethargy, muscle tremors, mild appetite loss |
| II – Down | 4.0–6.4 | Cold ears, dry eyes, sternal recumbency |
| III – Critical | <4.0 | Lateral recumbency, unconsciousness, and possible death |
Diagnosis
Observation is vital post-calving. Key indicators include lethargy, cold extremities, and poor appetite. No definitive test exists, but serum calcium below 6.4 mg/dL raises concern. Elevated liver and muscle enzymes (GOT, CPK), low serum phosphorus and magnesium, and alkaline urine may support diagnosis.
Treatment
Early intervention offers the best outcomes. Administer calcium borogluconate intravenously (400–800mL), followed by subcutaneous calcium salts. Oral supplementation pre- and post-parturition with calcium propionate is recommended due to its sustained action and absence of corrosive effects compared to calcium chloride. Caution is needed with Vitamin D analogues, as they may suppress the cow’s natural response to hypocalcemia.
DCAD (Dietary Cation Anion Difference)
Managing DCAD is key. Reducing sodium and potassium while increasing chlorides and sulphates helps acidify the blood, enhancing calcium mobilization. Monitor urine pH (ideal: 5.5–6.2) to guide dietary adjustments. Target DCAD between -50 to -100 meq/kg of feed.
Management
Proactive strategies trump reactive treatments. Avoid overfeeding calcium during the dry period and monitor BCS (keep below 3 out of 5). Ensure phosphorus adequacy, encourage feed intake, and minimize stress. High-risk cows deserve special attention around calving—oral calcium gels and calcium-rich diets are helpful in the early hours post-parturition.
Conclusion
Milk fever remains a preventable yet prevalent metabolic challenge in dairy farms. Strategic feeding, early detection, and timely intervention can significantly reduce animal loss. Prevention through vigilant postpartum monitoring and optimized nutrition should be prioritized to ensure herd health and farm profitability.
References
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Block, E. (1984). Manipulating dietary anions and cations for prepartum dairy cows to reduce the incidence of milk fever. Journal of Dairy Science. 67(12): 2939-2948.
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Green, H. B., Horst, R. L., Beitz, D. C., and Littledale, E. T. (1981). Vitamin D metabolites in plasma of cows fed a prepartum low-calcium diet for prevention of parturient hypocalcemia. Journal of Dairy Science 64(2):217-226.
