How can you diagnose and treat the case?
The disease that affects this cow is diagnosed through the following steps:
The case history.
In the case of lactating cow at grass, that has postpartum clinical signs in Spring, there is a high probability for hypomagnesemia (grass tetany) because the milk production depends mainly on grass feeding.
A cow has no magnesium storage, and grass has low concentrations of magnesium, the cow suffers magnesium deficiency causing the appearance of the clinical signs.
The clinical signs.
The affected cow shows some clinical signs, including:
- Hypersensitivity to touch.
- Muscle tremors.
- Staggering walk.
- Appears to be blind.
- Aggressive behavior.
- Frequent urination.
- Convulsions
Physical examination
The high body temperature during the acute attack occurs due to violent muscle activity.
The pulse rate and breathing are greatly increased, and sometimes the heart sounds are so loud and can be heard without a stethoscope.
Treatment of hypomagnesemia in cows
The injection of calcium and magnesium combination subcutaneously behind the shoulder and over the ribs is the best treatment.
It's recommended to use a combination of magnesium sulfate S/C firstly, followed by calcium borogluconate and magnesium hypophosphite I/V.
Prevention of hypomagnesemia (grass tetany)
Applying the preventative measures is the key to protect your lactating cow from postpartum hypomagnesemia, including:
- Provide the cow with high Mg concentrates daily.
- Use Magnesium oxide supplement into water.
- Feeding straw or hay which is rich in magnesium.
- Avoid grazing pastures with high amounts of slurry and/or N applied.
- Dusting pasture with magnesium oxide powder in the early morning.
- Supply mineral licks and magnesium boluses.
- Provide a mixture of oral supplements including salt licks, molasses, and hay.
This case is closely related to the same nutritional deficiency of its calf, so Dr.provet advises you to be careful and always expect your next visit.
Clinical signs of hypomagnesemia in calves
The affected calf will show some clinical signs, including:
Tetany, Convulsions.
Stiffness of gait.
The calf is easily frightened.
Fixed movement of the ear (Tremors)
Half-opened mouth.
The calf may die within 20-30 min
Treatment
placing the calf in a quiet place To avoid Convulsion.
Injection of Mg associated with Ca such as cold Mg, Mg carbonate (MgCo3) → 100ml I/V. but follow up of the pulse, heart rate should be considered to avoid the cardiac attack.
Injection of vit E, Selenium to help muscles return to the normal condition.
Control and prevention of the whole milk tetany
The only key to control and prevent this case is the Mg supply.
Supplementation of food by Magnesium carbonate or Magnesium sulfate by the dose that differs according to age as the following:
Finally, hypomagnesemia in cows (grass tetany) is a serious disease affecting both milk production, and cow health and activity, and it may end in death.
Written by: Dr. Mai Foda
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