All cull cows must be residue-free when sold for slaughter.  Cows culled for mastitis-related reasons may have been treated with antibiotics in their recent history. It is essential to check these cows to ensure withholding periods for meat have elapsed.

Withholding periods are set to ensure that when a drug or chemical is used in accordance with the directions on the label, there will be no residue above the relevant Australian Maximum Residue Limit.  If withholding periods are not adhered to, Australia’s domestic and export trade may be jeopardized.

To avoid errors, all cows treated with antibiotics (injection or intramammary) must be clearly identified. Many of the temporary markings used on treated cows work well during the withholding period for milk, but do not last the full length of the withholding period for meat.  It is essential to have a permanent identification system and written records to ensure withholding periods have expired before any animal is sold.

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Farm Guideline Introduction, 20 Technote 20.1

Keywords
Cull, withholding periods