In its latest CellCheck newsletter, AHI explains that the minimum dry periods and milk withholding times for antibiotic dry cow therapy (DCT) are there to ensure that no residue of antibiotic remains by the time the freshly calved cow is milked into the bulk tank. In the absence of quotas, some farmers will have milked on for a little longer than previous years, which may result in a shorter dry period for some cows. If you did this, then you need to double-check that the dry period of every cow treated is at least as long as the minimum dry period of the DCT used.

Early lactation is a high-risk time for bulk tank residues, particularly antibiotics, which is a serious food safety matter. Milk processors have stringent penalties if milk supplies are found to be positive for residues.

How to avoid antibiotic residue problems this spring:

  • Write down the dates of when cows were treated with DCT, and when their withholding periods are up (based on the manufacturer’s recommendations).
  • If cows calve early, make sure the minimum dry period has passed before putting her milk into the tank.
  • If you suspect an error in cow identity, treatment or calving date records, do not put the milk in the tank until the issue is resolved. Consult your milk processor immediately.
  • Many processors will offer an option to pre-test milk before collection in spring – avail of this to help ensure that your bulk tank is residue-free.
  • Finally, if you suspect any cows have been milked into the tank by mistake notify your milk processor immediately to avoid contaminating a full silo of milk.
  • Read more

    Vet Tommy Heffernan looks at selective dry cow therapy as an option.

    Aidan Brennan has recommendations for milk quality issues this coming spring.

    Farmer writes contributor James Mimnagh reflects on RELATED TOPIC