STOCK VETS VOICE
A vet administering pain relief while disbudding horns on a calf.
Horned cattle in a crush prior to dehorning.
What is pain relief? Words by: Lisa Whitfield
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by a veterinarian for a painful husbandry procedure?
usbandry procedures such as castrating animals over 6 LOCAL ANAESTHETIC months old, and dehorning, Local anaesthesia provides a temporary are provided for under new block from feeling pain. The drugs animal welfare regulations which came interfere with the transmission of pain into force recently. The purpose signals to the brain, from targeted of the new legislation is to areas where the local anaesthetic is allow normal husbandry deposited. procedures to continue to The most commonly used occur, while improving the local anaesthetic in cattle in welfare outcomes for animals New Zealand is lignocaine by providing specific guidance hydrochloride. Lignocaine HCl that pain relief must be used for stops the sensation of pain during Lisa Whitfield the acute phase while a procedure is these procedures. For the example of dehorning, carried out, and immediately after the following statement now applies: a procedure until the drug wears off. Its “A person must not dehorn a cattle beast effects last approximately 1.5 to 2 hours unless throughout the procedure the cattle on average following administration. beast is under the influence of pain relief Local anaesthetics do not have antithat is authorised by a veterinarian for the inflammatory effects, therefore do not purpose of the procedure” affect pain and discomfort experienced So what pain relief will be authorised over the days following a procedure during 76
the chronic phase while healing occurs. Local anaesthetic blocks would be considered a minimum standard for pain relief in situations where they can be used effectively.
NON-STEROIDAL ANTIINFLAMMATORIES (NSAIDS)
NSAIDs provide pain relief beyond the duration of the procedure by reducing inflammation produced by damaged tissues over the healing period. The use of an anti-inflammatory in addition to local anaesthetic for a painful procedure would be considered the gold standard regime for pain relief. (See Table 1).
WHAT IS THE DIFFERENCE BETWEEN THEM?
For the purpose of a painful procedure, the main difference between NSAIDs is the duration of action. Firstly, the use of any anti-inflammatory will be more desirable than none. Secondly, consider how long
Dairy Exporter | www.nzfarmlife.co.nz | July 2021
