Plus-Hex CLINICAL
Introduction
The RCVS Code of Professional Conduct for Veterinary Surgeons [ 1 ] states that euthanasia may be defined as‘ painless killing to relieve suffering’. It also recommends that‘ all practice staff involved in euthanasia are fully trained and a planned, rehearsed and coordinated approach is taken’.
Pre-planning for the euthanasia of exotic or nontraditional companion animals( NTCAs) can take time. This article has been developed to enable veterinary nurses( VNs) to feel confident when involved in the euthanasia of more unusual patients, and to ensure that the euthanasia process respects the animal ' s welfare and is stress free for the patient, the owner and the veterinary team.
The ownership of exotic pets, sometimes known as NTCAs, has increased over recent years, with the RSPCA estimating there to be 1.8 million reptiles, amphibians and invertebrates and 1.3 million indoor birds kept as pets in UK households, as of 2021 [ 2 ]. Additionally, the Ornamental Aquatic Trade Association( OATA) reported that over 100 million fish were kept as pets in the UK in 2022 [ 3 ].
Given the high numbers of NTCAs in domestic ownership, the veterinary profession has a duty of care towards these patients, including being able to provide correct euthanasia for these species if referral or treatment is not an option.
In January 2023, the BVA published its policy on NTCAs. Point 30 of this policy focuses on the Day One competencies for veterinary surgeons( VSs); namely, having the skills and knowledge to safely handle, examine, and provide first aid, pain relief and euthanasia for exotic pets [ 4 ]. VNs, too, need to have some knowledge and understanding of the handling and examination of these patients to assist VSs in their examinations and diagnosis.
A study exploring perceptions of the euthanasia of companion animals, published in 2023 [ 5 ], found that both VSs and pet owners wanted pets to have an experience that was free from pain and anxiety, and both reported that they appreciated the use of sedatives before euthanasia.
From this study, several recommendations were made to improve companion animal euthanasia, which the author believes can be incorporated into the euthanasia of NTCAs.
Recommendations included focusing on patient comfort before and during the procedure, the avoidance of pain, improving communication by allowing ample time to discuss the process with the owner in simple and easy-to-understand language, and keeping the owner and patient together.
With these recommendations in mind, the study [ 5 ] stated that alfaxalone was suitable for the provision of sedation before the administration of pentobarbital for euthanasia. It is recommended that the alfaxalone doses be taken directly from the most up-to-date formulary for NCTA species [ 5 ]. Pentobarbital doses for each of the species discussed in this article are provided in Table 1.
Table 1. Doses of pentobarbital for the euthanasia of exotic species, taken from the BSAVA Small Animal Formulary [ 6 ].
Species Small mammals Birds Reptiles Amphibians Fish
It is also important to note that these patients should be kept as close to their preferred optimum temperature zone( POTZ) as possible to facilitate better drug absorption. The use of red heat lamps would be beneficial, or heat pads can be used if a lamp is not available. Care should be taken with both of these options, as the animal may be unable to move away from the heat source and therefore the risk of burns is increased. Owners should be encouraged to ensure their animal ' s carrier is safe, secure and has a heat source inside, if applicable.
Arachnids
Dose 150 mg / kg 150 mg / kg 60 – 100 mg / kg 60 mg / kg 60 – 100 mg / kg
Arachnid species are relatively easy to induce in an induction chamber filled with isoflurane and oxygen, which will provide around 20 minutes of anaesthesia. A study in which Goliath birdeater spiders and Chilean rose spiders were anaesthetised found that 5 % isoflurane in 1 litre of oxygen in an induction chamber provided a mean induction time of 10 minutes and a mean recovery time of 30 minutes for the Goliath birdeater spider and 12.5 minutes for the Chilean rose spider [ 7 ]. It is worth noting that smaller species may try to escape up the tubing of the chamber, so the use of a double chamber is recommended.
Using the above procedure, 20 minutes of anaesthesia can be provided, allowing enough time for an injection of pentobarbital into the abdomen or intracardially. For the latter option, the patient is placed in dorsal recumbency and pentobarbital is injected into the pericardial sinus, which is located in the dorsal midline of the cranial third of the opisthosoma( Figure 1, page 30). A Doppler probe can be used on the dorsal opisthosoma to check for a heartbeat( normal pulse rate is 3 – 70 bpm) [ 8 ].
Volume 40( 6) • December 2025
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