Evaluation of an Aged Animal Assessment Tool Used For Quality-of-Life Assessment and End-of-Life Planning for Geriatric Zoo Animals
Kimberly Vinette Herrin1, MS, DVM, MANZCVS; Larry Vogelnest1, BVSc, MVS, MANZCVS; Frances Hulst1, BVSc, MVS; Gabrielle Tobias1, BVSc, MAppSc; Michelle Campbell-Ward2, BSc, BVSc, MANZCVS, DZooMed; Benn Bryant2, BVSc, MVS, MANZCVS; Benjamin Pitcher1, BSc, PhD
Early recognition of age-related changes guides appropriate intervention and directs end-of-life planning to support good welfare in aging zoo animals. In 2013, Taronga Conservation Society Australia implemented an aged animal assessment (AAA) tool to objectively assess quality of life to facilitate welfare-focused end-of-life management. The tool also provides opportunity to address age-related changes through medical treatment, nutrition and husbandry.1
AAAs are performed when an animal reaches 80% of the expected longevity for the species.1 The AAA objectively scores criteria that measure physical and psychologic health (compared with an animal in its prime) and includes behavioral assessment, species-specific criteria, curatorial and logistical imperatives. The tool generates a cumulative score that correlates with predetermined numeric ranges that suggest a recommended course of action: treatment, dietary or husbandry changes; end-of-life planning; or euthanasia.
To date, 137 AAAs have been performed on 90 animals from a variety of taxa. Thirty-three had 1–4 follow-up assessments at 6 mo or 1 yr. Four individuals were euthanized as a direct result of the initial AAA. Another 24 were euthanized based on follow-up AAAs or predetermined decisions to euthanize if conditions deteriorated. Approximately 50% of total cases remained stable while nine cases had improved scores following implementation of individualized care plans and early recognition of disease.
The AAA tool allows objective decision-making regarding quality of life of individual animals. Significant improvement in welfare of aged animals has been attributed to early recognition and intervention of age-related changes or recognition that euthanasia is warranted.
1. Vogelnest L, Talbot JJ. Quality-of-life assessment and end-of-life planning for geriatric zoo animals. In: Miller RE, Lamberski N, Calle PP, eds. Fowler’s Zoo and Wild Animal Medicine: Current Therapy. Volume 9. St. Louis, MO: Elsevier; 2019:83–91.