Efficacy of articaine hydrochloride for disbudding in goat kids and velvet antler removal in red deer, and novel disbudding methods for goat Kids: a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Palmerston North, New Zealand. EMBARGOED until 31 December 2021.

Abstract

Painful husbandry procedures are routinely performed in farm animals all over the world. Most of these procedures can be humanely performed under local anaesthesia. Lignocaine is the most commonly used local anaesthetic in veterinary medicine. Even though lignocaine is a cheap and effective local anaesthetic, its use in goat kids and deer has been a concern. In goat kids, lignocaine has been reported to produce toxicity following cornual nerve block. In deer, the presence of lignocaine residue in the harvested velvet antlers following ring block has been a concern as one of its metabolites, 2,6-dimethylaniline (DMA) has been classified as a possible carcinogen in humans. Articaine hydrochloride is an amide-type local anaesthetic with unique pharmacological properties such as rapid hydrolysis in plasma to an inactive metabolite and high lipid solubility. It is widely used in humans for local and regional nerve blocks in dentistry. Several studies in humans suggested that articaine hydrochloride was effective and safer than lignocaine. Given concerns on the use of lignocaine in goat kids and deer, a series of studies were conducted to evaluate the safety and efficacy of articaine hydrochloride as an alternative to lignocaine hydrochloride for disbudding in goat kids and velvet antler removal in deer. As there is a paucity of data on the toxicity of lignocaine in goat kids, the thesis has also investigated the toxicity of lignocaine hydrochloride in goat kids. In addition, novel analgesic and disbudding techniques for goat kids were evaluated.