Milk Fever in Beef Cows: Signs, Emergency Treatment and Prevention

Milk Fever in Beef Cows: Signs, Emergency Treatment and Prevention

By Dr Duncan Houston

An older beef cow that becomes weak or goes down around calving may have milk fever, but not every down cow has low calcium.

Grass tetany, calving-related nerve injury, pelvic trauma, toxic mastitis, metritis and several other emergencies can look similar. What matters most is how quickly the cow became affected, whether she is still standing, whether she can swallow, and whether she responds promptly to carefully administered calcium.

Milk fever can progress from mild tremors to recumbency, severe bloat, unconsciousness and death within hours. Delayed treatment also allows secondary muscle and nerve damage to develop simply from the cow remaining down. (Merck Veterinary Manual)

Quick Answer

Milk fever is clinical hypocalcaemia occurring around calving, most commonly from the onset of labour through the first three days of lactation.

A cow that is still standing but showing early signs may be treated with a veterinarian-directed oral calcium bolus or, in selected cases, subcutaneous calcium. A recumbent cow generally requires slow intravenous calcium with continuous heart monitoring. Oral calcium must not be given until the cow is standing, alert and swallowing normally. (Merck Veterinary Manual)

Milk Fever at a Glance

Question	Practical answer
What is milk fever?	Clinical hypocalcaemia causing impaired nerve, muscle, heart and gastrointestinal function
When does it occur?	Usually from the onset of calving to approximately three days after calving
Which beef cows are most at risk?	Older, multiparous, high-milking cows and cows with a previous episode or poorly balanced pre-calving ration
Does it cause a fever?	Usually no. Body temperature is often normal or below normal
What is the main early sign?	Trembling, shuffling, weakness or an unsteady gait
What is the classic advanced sign?	A quiet cow in sternal recumbency with cold ears and poor rumen movement
What treatment does a standing cow need?	Oral calcium or veterinarian-directed subcutaneous calcium
What treatment does a down cow need?	Slow intravenous calcium with heart monitoring
How quickly should treatment work?	Improvement often begins during the infusion; many cows stand within two hours
Can the cow relapse?	Yes, commonly within 12 to 24 hours
What if calcium does not work?	Reassess immediately for trauma, grass tetany, infection or another metabolic disorder

Most cases occur close to calving, and recumbent cows require urgent treatment because prolonged pressure rapidly damages muscles and nerves. (Merck Veterinary Manual)

What Is Milk Fever?

Milk fever is also called:

• Parturient paresis

• Periparturient hypocalcaemia

• Clinical hypocalcaemia

• Parturient paralysis

The condition develops when calcium leaves the bloodstream for colostrum and milk faster than the cow can replace it through intestinal absorption and mobilisation from bone.

Calcium is essential for:

• Skeletal muscle contraction

• Heart contraction

• Nerve transmission

• Rumen and intestinal movement

• Uterine contraction

• Bladder function

When blood calcium falls far enough, the cow loses normal muscle strength. This affects far more than her legs. The rumen becomes sluggish, swallowing weakens, cardiac output falls and the uterus may contract poorly. (Merck Veterinary Manual)

Why Is It Called Milk Fever if the Cow Has No Fever?

The name is historical and misleading.

Milk fever is a metabolic calcium disorder, not an infectious fever. Affected cows often have a subnormal body temperature, cold ears and cold lower limbs because circulation and muscle activity have deteriorated. A high temperature should raise concern for another or additional disease, particularly toxic mastitis, metritis or another systemic infection. (Merck Veterinary Manual)

Can Beef Cows Get Milk Fever?

Yes.

Milk fever is far more common in high-producing dairy cows, but it is a recognised problem in mature beef cows near calving and early lactation. Beef cases are often associated with older cows, high milk production, poorly balanced mineral programmes or pre-calving diets that interfere with normal calcium regulation. (Beef Research)

The relative rarity of milk fever in beef herds can make it easier to miss. Producers may assume a down cow has suffered calving paralysis or a pelvic injury and lose valuable treatment time.

The practical rule is:

An older cow that becomes weak or recumbent close to calving should be assessed for hypocalcaemia immediately, while also examining for injury, grass tetany and systemic disease.

Which Beef Cows Are at Greatest Risk?

Older Multiparous Cows

Risk increases with age and successive lactations.

Older cows often have:

• Greater colostrum and milk calcium losses

• Slower activation of vitamin D

• Reduced responsiveness to parathyroid hormone

• Less efficient mobilisation of calcium from bone

Heifers are much less likely to develop classic parturient paresis than mature cows. (PubMed Central (PMC))

High-Milking Beef Cows

Beef cows differ significantly in milk production.

A mature cow producing a large volume of colostrum and early milk may experience a calcium demand closer to that of a moderate-producing dairy cow than to that of a low-milking beef cow.

High-producing maternal breeds, dairy-influenced beef crosses and cows raising twins may deserve especially close observation, although individual ration and herd history remain more useful than breed stereotypes alone.

Cows With a Previous Episode

A previous milk-fever case identifies a cow whose calcium-regulation system has already failed during a transition period.

Record these cows and place them in a higher-monitoring group for future calvings.

High-Potassium Pre-Calving Diets

High potassium makes the cow more metabolically alkaline and reduces tissue responsiveness to parathyroid hormone. This impairs the cow’s ability to mobilise calcium rapidly around calving.

Potentially high-potassium feeds include:

• Heavily fertilised forage

• Manure-fertilised forage

• Some legume hays

• Some lush cool-season grasses

• Poultry litter or feeds containing substantial poultry litter

The full ration must be analysed rather than judging risk from the name of one ingredient. (Merck Veterinary Manual)

Inadequate Magnesium

Magnesium is required for normal parathyroid-hormone secretion and action.

A cow with inadequate magnesium intake or absorption may be less able to correct falling calcium. High dietary potassium can interfere with magnesium absorption, creating overlapping risks for hypocalcaemia and grass tetany. (Dairy)

Reduced Feed Intake Around Calving

Calving difficulty, weather stress, transport, sudden ration changes or poor access to feed can reduce intake at the exact time calcium demand is increasing.

The cow then has less dietary calcium available while still needing to mobilise calcium rapidly from her own reserves.

When Does Milk Fever Occur?

Most bovine milk-fever cases occur:

• Shortly before calving

• During calving

• Within the first 24 hours after calving

• Up to approximately three days after calving

A down cow two weeks after calving may still have a calcium problem, but another diagnosis becomes progressively more likely. (Merck Veterinary Manual)

Timing is therefore helpful, but it is not proof. Toxic mastitis, metritis, trauma and grass tetany can also occur during early lactation.

What Are the Stages of Milk Fever?

Stage 1: The Cow Is Still Standing

Early hypocalcaemia may produce more nervousness than sedation.

Signs can include:

• Fine muscle tremors over the flank or shoulders

• Ear twitching

• Head bobbing

• Shuffling of the rear feet

• Stiff or unsteady gait

• Mild ataxia

• Restlessness

• Bellowing

• Reduced appetite

• Reduced rumination

This stage may be brief and easily missed. Without treatment, the cow can progress to recumbency. (Merck Veterinary Manual)

What To Do

Treat this as urgent rather than waiting to see whether she goes down.

The cow may be suitable for a labelled oral calcium bolus or veterinarian-directed subcutaneous calcium, depending on severity and the herd protocol. She should not automatically receive intravenous calcium simply because she appears slightly weak. (Merck Veterinary Manual)

Stage 2: The Cow Is Down but Remains Sternal

This is the classic milk-fever presentation.

The cow may show:

• Inability to stand

• Sternal recumbency

• Quiet or dull behaviour

• Head turned towards the flank

• Dry muzzle

• Cold ears and lower limbs

• Reduced or absent rumen contractions

• Bloat

• Weak peripheral pulse

• Reduced heart-sound intensity

• Increased heart rate

• Reduced appetite

• Constipation

• Poor swallowing

The cow still has enough muscle control to maintain her chest-up position but requires immediate intravenous treatment. (Merck Veterinary Manual)

Stage 3: Lateral Recumbency, Coma and Shock

In advanced disease, the cow loses the ability to remain sternal and lies flat on her side.

Signs include:

• Extreme muscle flaccidity

• Severe bloat

• Weak or absent peripheral pulse

• Heart rate approaching 120 beats per minute

• Poor response to stimulation

• Progressive unconsciousness

• Coma

• Death

An untreated stage-3 cow may survive only a few hours. (Merck Veterinary Manual)

How Worried Should You Be?

Lower Immediate Risk

The cow:

• Is standing

• Is alert

• Swallows normally

• Has mild tremors or a slightly unsteady gait

• Is close to calving or has just calved

• Has normal breathing

• Has no evidence of trauma or infection

Action: Contact the herd veterinarian immediately and follow the standing-cow calcium protocol. Reassess frequently because stage 1 may progress quickly.

Moderate to High Risk

The cow:

• Is recumbent but remains sternal

• Has cold ears

• Is quiet or dull

• Has reduced rumen sounds

• Has a weak pulse

• Cannot rise despite trying

Action: This is an emergency requiring slow intravenous calcium and a full examination.

Critical

The cow:

• Is lying flat on her side

• Cannot maintain sternal recumbency

• Has severe bloat

• Has an absent swallow

• Is minimally responsive

• Has convulsions

• Has extremely weak or absent peripheral pulses

• Is struggling to breathe

Action: Obtain immediate hands-on veterinary treatment. Keep her sternal while assistance is being arranged.

Milk Fever or Grass Tetany?

These two metabolic diseases can both cause recumbency around calving, but their typical behaviour differs.

Feature	Milk fever	Grass tetany
Main deficiency	Calcium	Magnesium
Typical timing	Around calving and early lactation	Often on lush, rapidly growing pasture
Early behaviour	Trembling, weakness or mild restlessness	Hyperexcitability, nervousness and extreme sensitivity
Advanced behaviour	Quiet, flaccid and depressed	Stiff, paddling, convulsing or aggressive
Body temperature	Often below normal	May rise from muscular activity
Muscle tone	Reduced	Markedly increased
Response	Often rapid with calcium	Slower response and requires magnesium as well as calcium
Handling	Calm, careful handling	Minimal stimulation because handling can trigger seizures

A cow with violent tremors, stiff-legged movement, repeated paddling or seizures should be considered at risk of grass tetany. Combined calcium and magnesium treatment is commonly required, and unnecessary stimulation may trigger fatal convulsions. (Merck Veterinary Manual)

What Else Can Look Like Milk Fever?

Calving Paralysis or Nerve Injury

Difficult calving can damage the obturator, sciatic or related nerves.

Clues include:

• Hind legs splayed sideways

• One limb positioned abnormally

• Knuckling

• Normal alertness and appetite

• Failure to rise despite calcium

• History of prolonged labour or a large calf

Calcium may correct concurrent hypocalcaemia without fixing the nerve injury. (Merck Veterinary Manual)

Pelvic, Hip or Limb Trauma

Consider:

• Pelvic fracture

• Hip dislocation

• Femoral fracture

• Ruptured adductor muscles

• Stifle injury

• Spinal injury

Asymmetry, crepitus, severe local pain or one limb appearing shorter should move trauma higher on the list. (Merck Veterinary Manual)

Toxic Mastitis

Check every quarter.

Concerning signs include:

• Abnormal milk

• Hot, swollen or painful udder

• Cold, blue or gangrenous quarter

• Fever or hypothermia

• Dehydration

• Severe depression

• Rapid shock

Toxic mastitis may also cause secondary hypocalcaemia, making partial improvement after calcium misleading. (Merck Veterinary Manual)

Toxic Metritis

Inspect for:

• Foul-smelling uterine discharge

• Retained placenta

• Difficult calving

• Fever or hypothermia

• Depression

• Dehydration

• Poor appetite

Metritis may cause recumbency independently or occur alongside milk fever. (Merck Veterinary Manual)

Hypophosphataemia or Hypokalaemia

A cow may become brighter after calcium but remain unable to rise because another electrolyte abnormality or secondary muscle injury persists.

Blood testing becomes particularly important when mentation improves but weight bearing does not. (Merck Veterinary Manual)

Severe Ketosis or Fatty Liver

More typical in dairy cattle but possible in high-producing or poorly nourished beef cows.

Affected cows may be weak, anorexic and dull without the dramatic response expected after calcium.

Bovine Ephemeral Fever

In endemic regions, including parts of Australia, bovine ephemeral fever can cause fever, stiffness, lameness and recumbency. Calcium may produce partial temporary improvement, which can confuse the diagnosis. (PubMed)

Grain Overload, Bloat or Acute Abdominal Disease

Grain overload can cause:

• Rumen atony

• Depression

• Ataxia

• Diarrhoea

• Dehydration

• Collapse

Unlike classic milk fever, diarrhoea and dehydration are often prominent. (Merck Veterinary Manual)

When Is This an Emergency?

Contact a veterinarian immediately when a cow close to calving or recently calved:

• Cannot stand

• Is lying flat on her side

• Has cold ears and a weak pulse

• Has severe bloat

• Has an absent swallow

• Is convulsing

• Is bleeding heavily

• Has a foul uterine discharge with systemic illness

• Has an abnormal, painful udder and is severely depressed

• Has an obviously displaced or fractured limb

• Fails to improve during or shortly after calcium

• Goes down again after initial treatment

Do not leave a newly recumbent cow until the next morning. Pressure injury to nerves and muscles can begin within hours, especially on concrete or hard ground. (Merck Veterinary Manual)

What To Do Right Now

1. Call the Herd Veterinarian

Describe:

• Cow identification and age

• Number of previous calvings

• Time relative to calving

• Whether calving was difficult

• Whether she stood after calving

• Whether she is sternal or lateral

• Whether she can swallow

• Body temperature

• Udder and uterine findings

• Current ration and mineral programme

• Previous calcium treatment

2. Keep the Cow Sternal

A cow lying flat on her side is at risk of:

• Severe bloat

• Regurgitation

• Aspiration pneumonia

• Pressure damage to forelimb nerves

• Further muscle injury

Roll her onto her chest and support her with straw bales if necessary. Keep the head and neck in a position that allows saliva and rumen fluid to drain rather than enter the airway. (Merck Veterinary Manual)

3. Move Her Onto Deep Bedding and Good Footing

Use:

• Deep sand

• Deep dry straw

• Dry earth

• A sheltered grass area in suitable weather

Hard concrete dramatically increases pressure damage and makes successful attempts to rise less likely. (Merck Veterinary Manual)

4. Do Not Give an Oral Bolus or Drench to a Down Cow

A recumbent cow may not swallow safely.

Calcium gels, liquids and drenches can enter the airway or injure the pharynx and oesophagus. Oral calcium should only be given after the cow is standing, alert and swallowing normally. Coated boluses are safer than gels or drenches. (Merck Veterinary Manual)

5. Do Not Administer IV Calcium Rapidly

Calcium can cause fatal cardiac arrhythmias when administered too quickly.

Intravenous administration requires correct venous placement, asepsis and continuous monitoring of the heart rate and rhythm. This is not a treatment to learn during an emergency from an app screen. (Merck Veterinary Manual)

6. Keep the Calf Safe

Prevent the calf from being trapped, stepped on or repeatedly pulling at the udder while the cow is unstable.

Ensure the calf receives adequate colostrum or milk by an alternative safe method when the cow cannot nurse normally.

7. Do Not Drag or Suspend the Cow Improperly

Do not:

• Drag her unprotected across concrete

• Pull her by the head or tail

• Transport her hanging from hip clamps

• Leave her suspended in clamps

Hip lifters may have a temporary examination or assisted-standing role when used by experienced people, ideally with a chest sling. They should never become a method of prolonged suspension. (Merck Veterinary Manual)

How Do Veterinarians Diagnose Milk Fever?

Diagnosis usually combines:

• Timing relative to calving

• Clinical stage

• Heart and pulse findings

• Rumen motility

• Body temperature

• Musculoskeletal examination

• Udder and reproductive-tract examination

• Blood testing

• Response to calcium

A dramatic response to intravenous calcium strongly supports milk fever, but response alone is not infallible. Other diseases may coexist, and some regional disorders may temporarily improve with calcium. (Merck Veterinary Manual)

Blood Sampling

When practical, collect blood before calcium is administered.

Useful tests may include:

• Total and ionised calcium

• Magnesium

• Phosphorus

• Potassium

• Glucose

• Beta-hydroxybutyrate

• Creatine kinase

• AST

• Markers of inflammation and organ function

A post-treatment calcium result cannot confirm the original diagnosis because the infusion has altered the blood concentration. Merck notes that a correctly stored pretreatment sample may still be submitted later if the cow fails to respond. (Merck Veterinary Manual)

How Is Milk Fever Treated?

Treatment of a Standing Cow

A standing cow with early clinical signs may receive:

• A labelled oral calcium bolus

• A second bolus approximately 12 hours later

• Veterinarian-directed subcutaneous calcium in selected cases

Acidogenic oral calcium salts, commonly calcium chloride or calcium sulfate, are absorbed quickly and support the cow’s own calcium-regulation mechanisms. A typical adult-cow bolus provides approximately 40 to 55 g of elemental calcium, although products vary and the label must be followed. (Merck Veterinary Manual)

Do Not Give IV Calcium to a Normal Standing Cow

Prophylactic intravenous calcium in a cow without clinical signs can cause marked temporary hypercalcaemia, suppress the cow’s own calcium-mobilisation response and leave blood calcium lower several hours later.

Intravenous treatment is reserved for clinical recumbent cows, not every high-risk cow after calving. (University of Minnesota Extension)

Treatment of a Recumbent Cow

A recumbent stage-2 or stage-3 cow requires intravenous calcium.

A common adult-cow treatment is:

• 500 mL of 23% calcium gluconate or calcium borogluconate

• Approximately 8 to 12 g of elemental calcium, depending on the formulation

• Administered intravenously once

• Given slowly over approximately 10 to 20 minutes

• With continuous cardiac monitoring

The exact product, dose and route must follow the product label and veterinarian’s protocol. Formulations differ between countries and manufacturers. (Merck Veterinary Manual)

Why Must IV Calcium Be Given Slowly?

Intravenous calcium transiently raises blood calcium to well above normal.

Potential complications include:

• Bradycardia

• Premature ventricular contractions

• Other dysrhythmias

• Collapse

• Fatal cardiac arrest

The veterinarian should monitor the heart by auscultation or pulse throughout administration. If bradycardia or a severe rhythm disturbance develops, the infusion is stopped until the rhythm normalises and may then be resumed more slowly. Endotoxaemic cows are particularly susceptible to calcium-associated dysrhythmias. (Merck Veterinary Manual)

The four-to-five-minute administration proposed in the original draft is too rapid for a routine adult-cow infusion.

Is More Calcium Better?

No.

A standard adult treatment already provides more calcium than is required to restore normal blood concentrations in most cows. Research has not shown an improved recovery rate from administering higher doses. Excess calcium increases hypercalcaemia, cardiac and relapse risks. (PubMed)

Which IV Calcium Product Is Preferred?

For uncomplicated milk fever, calcium gluconate or borogluconate without unnecessary additional electrolytes is generally preferred.

Products containing magnesium, phosphorus, dextrose or potassium may be useful when another deficiency has been diagnosed or strongly suspected. They should not automatically replace a straightforward calcium product because some additional components may be unnecessary or harmful. (Merck Veterinary Manual)

What Response Should You Expect?

During successful treatment, you may notice:

• Stronger heart sounds

• Slower heart rate

• Stronger peripheral pulse

• Muscle tremors

• Increased awareness

• Belching or resumed rumen activity

• Defecation or urination

• Attempts to rise

Approximately three-quarters of recumbent cows with genuine parturient paresis are expected to stand within two hours of treatment. (Merck Veterinary Manual)

Do not chase or force the cow up during the infusion. Clear the area and allow her to rise when coordinated enough to do so.

Oral Calcium After IV Treatment

Once the cow is:

• Standing

• Alert

• Swallowing normally

give a labelled oral calcium bolus according to the veterinarian’s protocol, followed by a second dose approximately 12 hours later.

Do not bolus a cow that has failed to rise after IV calcium. She may choke, and the failure to stand suggests that normal swallowing and muscular function have not returned. (University of Minnesota Extension)

Can Calcium Be Given Subcutaneously?

Subcutaneous calcium is a possible veterinarian-directed treatment for selected standing cows or as relapse support.

A commonly described protocol uses 500 mL of 23% calcium gluconate divided across at least two sites behind the shoulders. Strict asepsis is required because calcium is irritating and injection-site infection can occur.

Products containing dextrose or formaldehyde should not be administered subcutaneously because they are especially irritating. (Merck Veterinary Manual)

Should Calcium Be Given Intraperitoneally?

No routine intraperitoneal treatment should be attempted.

Blind placement creates risks of:

• Injection into a hollow organ

• Peritonitis

• Kidney or retroperitoneal deposition

• Visceral injury

Safer and more predictable routes are available. (Merck Veterinary Manual)

What if the Cow Does Not Stand After Calcium?

Failure to rise does not automatically mean the cow needs another bottle of calcium.

Reassess for:

• Obturator or sciatic nerve injury

• Pelvic or femoral fracture

• Hip dislocation

• Severe pressure myopathy

• Hypomagnesaemia

• Hypophosphataemia

• Hypokalaemia

• Toxic mastitis

• Metritis

• Peritonitis

• Severe ketosis

• Bloat or abdominal disease

A cow may have had milk fever initially but developed enough muscle and nerve damage during recumbency to remain down after her blood calcium has normalised. (Merck Veterinary Manual)

When Should the Diagnosis Be Reconsidered?

Reconsider the diagnosis when:

• There is no improvement during or immediately after the infusion

• Mentation remains severely abnormal

• The cow cannot maintain sternal recumbency

• One limb is positioned abnormally

• The cow shows severe pain

• The udder or uterus is abnormal

• She remains unable to bear weight after two hours

• She becomes down again repeatedly

A second IV calcium treatment should not be given automatically without reassessing the heart, hydration, electrolytes and alternative diagnoses.

Nursing Care for the Down Cow

Correcting the blood calcium is only the beginning if the cow remains recumbent.

Maintain Sternal Recumbency

Keep the cow chest-down.

If she falls onto her side, correct her position promptly to reduce:

• Bloat

• Regurgitation

• Aspiration

• Brachial plexus injury

• Radial nerve damage

Straw bales can be used to support the shoulders. (Merck Veterinary Manual)

Turn the Cow Regularly

Tilt or roll the cow from one side to the other approximately every six to eight hours.

This reduces prolonged pressure on:

• Thigh muscles

• Sciatic nerve

• Peroneal nerve

• Shoulder muscles

• Forelimb nerves

Frequent repositioning is labour-intensive, but it is one of the most important elements of down-cow nursing. (Merck Veterinary Manual)

Provide Deep Bedding

Deep sand provides excellent drainage, grip and pressure relief. Deep dry straw over a supportive base is another option.

Protect the cow from:

• Rain

• Cold wind

• Heat

• Mud

• Slippery concrete

Provide Feed and Water Within Reach

Offer:

• Palatable hay

• The normal early-lactation ration

• Clean water

• An appropriate mineral source

Remove rejected or saliva-soaked feed rather than allowing it to spoil beside the cow.

Manage Pain and Hydration

Pain from muscle and nerve damage reduces the cow’s willingness to eat and attempt to stand.

Veterinary care may include:

• Appropriate anti-inflammatory medication

• Fluid therapy

• Treatment of ketosis

• Correction of other electrolytes

• Monitoring of urine and muscle enzymes

Assist Standing Carefully

Hip lifters or slings may be used for short assisted-standing sessions by trained people.

The cow should never be suspended for prolonged periods or transported hanging from clamps. Continued clamp pressure causes pain and tissue damage. (Merck Veterinary Manual)

Can Milk Fever Recur?

Yes.

Approximately 25% to 40% of recumbent cows that rise after IV calcium may become recumbent again, commonly within 12 to 24 hours, if relapse prevention is not provided. (Merck Veterinary Manual)

Relapse occurs partly because the large IV dose causes temporary hypercalcaemia, suppressing the cow’s own parathyroid-hormone response.

Reduce relapse risk by:

• Giving oral calcium once she is standing and swallowing

• Repeating the oral dose as directed, commonly 12 hours later

• Providing immediate access to an appropriate lactation ration

• Monitoring closely for at least 24 hours

• Investigating concurrent disease

What Is the Prognosis?

The prognosis is generally good when:

• Treatment begins early

• The cow remains sternal

• She responds promptly to calcium

• She rises within two hours

• No traumatic injury is present

• She continues eating and drinking

• Good nursing care is available

The prognosis becomes more guarded when:

• Recumbency has lasted many hours

• The cow remains lateral

• She has severe bloat

• There is no response to calcium

• She cannot bear weight

• There is nerve or muscle injury

• She has toxic mastitis or metritis

• She develops pressure sores

• Appetite is poor

Animal welfare must guide prolonged down-cow management. A cow that becomes listless, stops eating, develops major pressure wounds or shows no meaningful attempts to rise despite appropriate treatment should be reassessed promptly for humane euthanasia. (Merck Veterinary Manual)

How Can Milk Fever Be Prevented in Beef Cows?

Test the Pre-Calving Forage and Ration

Analyse:

• Calcium

• Phosphorus

• Magnesium

• Potassium

• Sodium

• Sulfur

• Dry matter

• Energy and protein

A mineral bag cannot correct an unknown forage problem reliably.

Forage mineral concentrations vary with:

• Soil

• Fertiliser

• Manure application

• Plant species

• Maturity

• Harvest

• Storage

Beef-herd prevention should begin with the complete ration rather than one generic free-choice mineral recommendation. (University of Missouri Extension)

Avoid Excessively High-Potassium Close-Up Forages

Where possible, use lower-potassium forage for high-risk cows during the final weeks before calving.

This may involve:

• Selecting a different hay source

• Diluting high-potassium forage with lower-potassium feed

• Avoiding heavily manure-fertilised forage for the close-up group

• Reviewing poultry-litter inclusion

• Testing mineral interactions rather than calcium alone

Ensure Adequate Magnesium

Magnesium supports calcium absorption and parathyroid-hormone function.

The correct amount depends on the full ration and potassium load. Free-choice magnesium intake is variable, so high-risk programmes may require a more controlled delivery method.

Do Not Blindly Remove Calcium From the Diet

A truly effective low-calcium prevention diet must generally provide less than approximately 20 g of calcium per cow each day. This is extremely difficult to achieve using normal forage-based rations.

Partially reducing calcium without reaching a genuinely low level may provide little benefit while risking an unbalanced ration. (Merck Veterinary Manual)

The practical objective is not “feed no calcium before calving.” It is:

Feed a balanced close-up ration that allows the cow’s calcium-control system to activate normally.

Should Beef Cows Be Fed a Negative-DCAD Diet?

Negative-DCAD diets have strong evidence in closely managed dairy transition groups.

The ration is made acidogenic for approximately three weeks before calving by controlling sodium and potassium while increasing chloride and sulfur. This improves parathyroid-hormone responsiveness, intestinal calcium absorption and mobilisation from bone. (Merck Veterinary Manual)

However, successful use requires:

• Known forage mineral concentrations

• Controlled daily intake

• Accurate mixing

• Monitoring of urine pH

• Prevention of overacidification

• Veterinary and ruminant-nutrition oversight

This makes full negative-DCAD programmes much more difficult in pasture-based beef cows or groups relying on variable free-choice intake.

As a practical inference from the dairy evidence, DCAD is most defensible in a controlled high-risk beef close-up group rather than as a blanket mineral strategy for every pregnant cow.

Monitor Urine pH When Using Anionic Diets

Urine pH confirms whether the ration is actually acidifying the cow.

Merck gives a mean urine-pH target around 6.5 and warns that values below approximately 5.5 suggest overacidification, impaired feed intake and uncompensated metabolic acidosis. Target ranges vary by breed and protocol, so the nutritionist’s monitoring plan should be followed. (Merck Veterinary Manual)

Should Every Beef Cow Receive Oral Calcium After Calving?

Not automatically.

Routine prophylactic calcium for every clinically normal cow is not strongly supported, and intravenous prophylaxis should be avoided.

A targeted oral-bolus programme may be considered for cows with:

• A previous milk-fever episode

• Advanced age

• High milk production

• A difficult nutritional transition

• Herd-level history of clinical cases

The decision should account for the product label and the actual herd problem. (Merck Veterinary Manual)

Identify High-Risk Cows Before Calving

Mark and monitor:

• Previous cases

• Older cows

• High-producing maternal cows

• Dairy-influenced cows

• Cows fed a suspect ration

• Cows with poor close-up intake

• Cows experiencing difficult calving

Observe them several times daily around calving where practical.

Provide Good Footing

A mildly hypocalcaemic cow may become permanently injured if she slips.

Provide:

• Dry calving areas

• Non-slip footing

• Deep bedding

• Calm handling

• Adequate room to rise

Milk-fever prevention and down-cow prevention are closely linked. (Merck Veterinary Manual)

Keep Accurate Records

Record:

• Cow identification

• Age and parity

• Calving date

• Calving difficulty

• Diet and forage batch

• Clinical signs

• Calcium product and route

• Response time

• Relapse

• Outcome

Several cases within one calving season should trigger a formal ration and herd-health investigation rather than simply purchasing more calcium bottles.

Common Milk-Fever Mistakes

Assuming Every Down Cow Has Milk Fever

Calving paralysis, fractures, grass tetany, mastitis and metritis are common and important alternatives.

Giving IV Calcium Over Four or Five Minutes

This is dangerously fast for a routine adult-cow infusion. Administer slowly over approximately 10 to 20 minutes while monitoring the heart.

Giving Oral Calcium to a Recumbent Cow

A down cow may choke or aspirate. Wait until she is standing, alert and swallowing.

Using Calcium Gel or Liquid Instead of a Bolus

Gels and drenches create avoidable aspiration and mucosal-injury risks. A properly coated bolus is preferred.

Giving Repeated IV Bottles Without Reassessment

More calcium is not automatically better and can produce fatal dysrhythmia or rebound hypocalcaemia.

Ignoring the Udder and Uterus

Toxic mastitis and metritis may cause recumbency or coexist with hypocalcaemia.

Leaving the Cow in Lateral Recumbency

This increases bloat, aspiration and nerve damage.

Leaving Her on Concrete

Pressure damage and poor footing rapidly worsen the prognosis.

Dragging or Suspending Her Improperly

Movement and lifting must protect her skin, muscles, nerves and welfare.

Restricting Calcium Without Analysing the Ration

An ineffective half-low-calcium ration may be worse than a properly balanced conventional ration.

Using Anionic Salts Without Monitoring

Overacidification can suppress intake and create another metabolic problem.

Frequently Asked Questions

Can beef cows really get milk fever?

Yes. It is less common than in high-producing dairy cattle but occurs in older, high-milking beef cows around calving, particularly when nutritional and mineral risk factors are present. (Beef Research)

Does milk fever cause a high temperature?

Usually not. Many affected cows have a normal or low temperature with cold ears and limbs. Fever suggests that infection or another disease may also be present.

How fast should IV calcium work?

Heart and pulse quality often improve during administration. The cow may tremble or attempt to rise soon afterwards, and approximately 75% of genuine recumbent milk-fever cases are expected to stand within two hours. (Merck Veterinary Manual)

Can I give an oral calcium bolus to a down cow?

No. Oral calcium should only be given when the cow is standing, alert and swallowing normally. A recumbent cow generally requires intravenous treatment first. (University of Minnesota Extension)

Can the cow go down again after treatment?

Yes. Relapse commonly occurs within 12 to 24 hours. Oral calcium follow-up, adequate feed intake and close monitoring reduce the risk. (Merck Veterinary Manual)

Final Thoughts

Milk fever is less common in beef cows than in dairy cattle, but it can still kill a mature cow quickly and should never be dismissed.

The most important points are:

1. Milk fever is clinical hypocalcaemia, not an infectious fever.

2. Most cases occur from calving through the first three days of lactation.

3. Older, high-milking and previously affected cows are at greatest risk.

4. Early cases may show tremors and excitability while the cow is still standing.

5. Advanced cases become quiet, cold, weak and recumbent.

6. A cow lying flat on her side is critical.

7. Standing cows are generally managed with oral or veterinarian-directed subcutaneous calcium.

8. Recumbent cows generally require intravenous calcium.

9. IV calcium must be given slowly over approximately 10 to 20 minutes with heart monitoring.

10. More calcium is not automatically better.

11. Oral boluses must not be given until the cow stands and swallows normally.

12. Relapse is common during the following 12 to 24 hours.

13. Failure to rise requires investigation for nerve injury, fracture, grass tetany, mastitis, metritis and other disorders.

14. Sternal positioning, deep bedding and regular turning protect the down cow from secondary damage.

15. Prevention begins with forage analysis, balanced magnesium and potassium management and a properly formulated pre-calving ration.

16. Negative-DCAD programmes require precision and monitoring and should not be improvised in pasture-based beef herds.

The mistake that causes the most harm is seeing a down cow, assuming calcium will fix everything, and failing to examine what else may have happened during calving. Treat hypocalcaemia quickly, but continue looking for trauma, infection and concurrent metabolic disease until the cow is standing, eating and behaving normally.

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ASK A VET™ can help organise calving history, ration analyses, mineral records, treatment response and relapse monitoring while producers work directly with their attending livestock veterinarian. A cow that cannot stand, is lying flat, has severe bloat, is convulsing or fails to respond to calcium still requires immediate hands-on veterinary care.