Lactation Tetany:
Syn: Grass Tetany, Hypomagnesemic Tetany, Grass Staggers, Wheat Pasture Poisoning
- Highly fatal disease of all classes of ruminant and reaches highest incidence in lactating cows.
- It is characterized by hypomagnesemia, hypocalcemia, muscular spasm, convulsion and death.
Epidemiology:
- Species: cattle, buffalo, ewes and does are affected.
- Calves affected at 2-4 months of age
- 4-7 years’ age group is affected.
- Mostly females are affected.
- Usually occurs in cow in first 2 months of lactation and 1-4 weeks after lambing in ewes
- High yielder cows are more prone to this disorder
Etiology:
- Dietary deficiency of magnesium
- Young green grasses are deficient in Mg and rich in K and N
- Soil deficient in Mg- sandy soils are usually deficient in Mg
- Heavy application of fertilizers like K,N also reduces Mg availability.
- Diarrhea may lead to loss of Mg and decreased absorption of Mg
- Mg absorption from rumen are low when potassium and nitrogen intakes are high.
- Starvation for 24-48 hour
- Increased demand of Mg for growth of fetus.
Clinical Finding:
Acute:
- Animal may be found dead
- Staggering gait
- Sudden anorexia
- Falling on ground
- Unusual alertness
- Grunting of teeth
- Muscle twitching- prickling of eggs
- Frothy mouth
- Hyperesthesia, tetany
- Opisthotonus and death
Sub-acute:
- Walks stiffly
- Hyper sensitive to touch and sound
- Urinate and defecate frequently
Chronic form:
- Dullness
- Emaciation
- Poor appetite
- Decreased milk production
Treatment:
- Pentobarbitone@ 3 mg/kg, 8-10 ml of 200 mg/ml solution for adult cow, IV
- Intravenous administration of 40% calcium borogluconate + 25% magnesium sulphate for cattle, 50 mL for sheep.
- Injection of MgSO4 @ 100-150 mL SC
- Animal must be provided with concentrate/hay treated with 60g of Mg oxide daily to ensure adequate dietary intake and prevent relapse.
- Daily oral supplement of Mg oxide; 60 g to cattle and 10g to sheep.
- Dairy animal should be provided with comfortable shelter during winter.
- Hay should be provided along with green.