Metabolic Diseases in Dairy Cows - Study Notes

Metabolic Diseases in Dairy Cows

  • Transition Period
    • Timeframe: From 3 weeks before (close-up) to 3 weeks after (postpartum) parturition.
    • Close-up Phase:
    • Critical to prepare the maternal nutritional health for upcoming lactation.
    • Improper nutrition changes can lead to metabolic diseases postpartum.
    • Postpartum Phase:
    • Characterized by negative energy balance (nutritional intake < energy output for lactation).
    • Increased risk for parturient diseases:
      • Retained fetal membrane.
      • Metritis.
      • Hypocalcemia.
      • Ketosis.
      • Abomasum displacement.

Major Parturient Diseases in Dairy Cows

  • Metabolic Diseases:

    • Retained fetal membrane
    • Puerperal Metritis
    • Ketosis (Fatty liver)
    • Abomasum displacement
    • Milk Fever (Parturient paresis)
    • Downer cow syndrome

  • Infectious Diseases:

    • Mastitis

  • Others:

    • Hoof diseases

Milk Fever (Parturient Paresis)

  • Definition:

    • An afebrile disorder in high-producing dairy cows occurring at or soon after parturition.
    • Symptoms: changes in mentation, generalized paresis, circulatory collapse.

  • Causes:

    • Sudden drop in blood calcium levels at the start of lactation; most common in high-yielding cows over 5 years.
    • Jerseys are more susceptible to this condition.

Effects of Hypocalcemia

  • Smooth Muscle Function:
    • Affects gastro-intestinal movement, uterine contractions, and recovery of the uterus.
    • Delays RFM recovery, increasing chances of metritis and impacting reproductive efficiency.
  • Negative Energy Balance:
    • Impacts milk production, dry matter intake, ketosis, fatty liver, and abomasum displacement.

Clinical Signs of Milk Fever

  • Onset:
    • Symptoms typically arise within 72 hours post-partum, leading to issues such as dystocia, uterine prolapse, and retained fetal membranes.
  • Stages of Symptoms:
    • Stage 1:
    • Cow can stand; shows hypersensitivity, excitability, unsteady gait, muscle tremors, twitching ears, head bobbing.
    • Stage 2:
    • Unable to stand but can maintain sternal recumbency; depression, anorexia, dry muzzle, cold extremities, increased heart rate, bloat.
    • Stage 3:
    • Loses consciousness, complete muscle paralysis; may die within hours.

Treatment of Milk Fever

  • Intravenous Therapy:

    • Administer Calcium (1g per 45 kg BW), often using Calcium gluconate; ensure slow administration (10-20 minutes).

  • Response:

    • Most cows (75%) should stand within 2 hours of treatment.

  • Repeat Treatment:

    • Some cows may require repeat treatments due to relapses.

Prevention of Milk Fever

  • Diet Management:
    • Feed low calcium and high phosphorus diets pre-calving.
    • Preventive treatment with calcium at calving and Vitamin D3 supplementation.
    • Synthetic bovine PTH administration may also aid prevention.

Ketosis in Dairy Cows

  • Definition:

    • A metabolic disease characterized by weight loss, pica, decreased milk yield, and neurologic abnormalities, typically occurring within the first 6 weeks of lactation.

  • Causes:

    • Can be triggered by going off feed; linked to factors like retained fetal membranes and environmental stresses leading to negative energy balance post-partum.

  • Clinical Signs:

    • Initial signs: slight decrease in feed intake, drop in milk production, lethargy, weight loss.
    • Cows may refuse grain; exhibit a bizarre appetite for coarse materials (hay, straw).
    • Possible acetone smell on breath, urine, and milk.

Treatment of Ketosis

  • Immediate Admin:
    • IV administration of 500ml of 50% glucose and glucocorticoids; oral propylene glycol.
    • Treatment may need to be repeated if relapse occurs.

Prevention of Ketosis

  • Management Strategies:
    • Eliminate all predisposing conditions; ensure cows calve with a body condition score (BCS) of 3.5.

Retained Fetal Membranes (RFM)

  • Definition:

    • Occurs when fetal membranes remain attached beyond 12 hours post-calving; incidence of 7-15%.

  • Consequences:

    • Increased chances of metritis, delayed conception, increased inter-calving period, decreased milk yield.

Treatment of RFM

  • Management Approaches:
    • If no systemic signs present, wait 72 hours before treatment.
    • Manually unbutton membranes; if persistent, use antibiotics and insert pessaries.

Downer Cow Syndrome

  • Definition:

    • A cow that remains in sternal recumbency for 24 hours post-initial recumbency; typically bright and alert but unable to rise.

  • Nursing Care:

    • Move cows to clean, dry areas, alternate sides for comfort, and provide food/water.
    • Consider using hip clamps for cows that can nearly stand.