Preliminary Evaluation of Risks and Benefits of a Comprehensive Preventive Health Program at Disney’s Animal Kingdom
Department of Veterinary Services, Disney’s Animal Kingdom, Lake Buena Vista, FL, USA
Abstract
The ultimate goal of any veterinary medicine program is prevention or early detection of disease. However, due to the difficulties associated with diagnosis and treatment of disease in wild animals, intervention often occurs in later stages, confounding diagnosis and therapy. This paper describes the initial development, implementation, and “risks versus benefits” of a comprehensive preventive health program at one institution.
Guidelines for diagnostic and prophylactic treatments (including deworming and vaccination) were developed by the veterinary staff for each taxonomic group in the collection based on common disease problems associated with the species and region of the country. Examples of these guidelines are shown in Tables 1 and 2. Elective procedures were performed using manual, chemical, or mechanical restraint. A retrospective review of the medical records for one calendar year was performed. Each procedure was evaluated in the following categories: complications associated with the procedure; presence of clinical signs detected prior to examination; normal, minor, or major abnormalities on physical exam; treatment required; and type of restraint used. Due to the size of the collection and scheduling/capture logistics, not all animals were examined during the study period.
Table 1. Walt Disney World animal programs preventive medicine protocol for the domestic cow (Bovidae).
Annual procedures (the following procedures will be performed on each animal every year):
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Procedures:
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Complete physical exam
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Check transponder
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Check body weight
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Diagnostics:
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Blood collection for:
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CBC, biochemical profile, fibrinogen, serum bank
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Serology for brucellosis, Johne’s ELISA, and Ag 85 - serum
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MCF PCR for wildebeest only
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Fecal collection for direct, O&P, Cryptosporidia ELISA
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Fecal culture for enteric pathogens
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TB test - 0.1 ml PPD bovis ID caudal tailfold and/or cervical; read at 72 hours
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Prophylactic treatments:
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Vitamin E - 1 ml/18 kg IM
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Vaccinations:
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Clostridial 8-way
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Tetanus toxoid
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Imrab 3
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Consider EEE vaccination for select species.
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Deworming:
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Routine deworming with ivermectin at time of annual exam
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Additional procedures:
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Semiannual fecal collection for direct smear, O&P; deworming as indicated by results
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Quarantine procedures:
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Unless otherwise specified by the veterinary staff in conjunction with the curatorial staff, all animals will be quarantined for a minimum of 30 days according to the WDW Animal Programs Quarantine Protocols.
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Procedures:
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Same as for annual exam, also placement of transponder, ear notch/tattoo if necessary.
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Diagnostics:
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Same as for annual exam, three weekly fecals for P&O, Johne’s culture, one sample for rota/corona EM; serology for Bluetongue, BVD, Leptospirosis, IBR, PI3, EEV, MCF; trace mineral panel
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Neonatal procedures:
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See neonatal ungulate protocol
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Table 2. Walt Disney World animal programs preventive medicine protocol for psittacines
Annual procedures (the following procedures will be performed on every animal every year):
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Procedures:
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Complete physical exam
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Check transponder
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Check body weight
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Whole body radiographs
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Diagnostics:
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Blood collection for:
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CBC, biochemical profile, EPH; bile acids and bank serum/plasma, volume permitting
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Polyoma antibody and antigen if breeding bird
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Chlamydia antibody titer
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Fecal collection for direct, O&P, Gram’s stain, acid fast stain
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Cloacal culture for enteric pathogens and Chlamydia antigen
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Fecal Giardia ELISA (cockatiels)
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Prophylactic treatments:
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Vaccinations:
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Polyoma virus vaccine for breeding birds - two vaccinations 2 weeks apart, then annual booster
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Deworming:
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Routine deworming with ivermectin at time of annual exam
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Additional procedures:
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Semiannual fecal collection for direct smear, O&P; deworming as indicated by results
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Quarantine procedures:
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Unless otherwise specified by the veterinary staff in conjunction with the curatorial staff, all animals will be quarantined for a minimum of 30 days according to the WDW Animal Programs Quarantine Protocols
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Procedures:
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Same as for annual exam, also placement of transponder, preferred location is in pectoral muscles
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Diagnostics:
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Same as for annual exam, PBFD antigen, ± Aspergillus antibody titer, three weekly fecals for P&O, direct, Gram’s stain, and acid-fast stain
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Neonatal procedures:
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New hatchlings will be examined opportunistically for signs of unabsorbed yolk, congenital defects, body condition, and external parasites
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During calendar year 1999, 672 animals (356 mammals, 284 birds, 32 herps) were individually examined for elective health evaluations. Table 3 shows the numbers of complications and problems detected during these procedures. Overall, the risk of complications was very low (5.9% of all procedures performed). Abnormalities were found in 277 cases (41.2%), although only 10.7% of individuals examined had clinical signs detected by Animal Care staff prior to evaluation. Approximately 43.3% (120/277) of the abnormalities discovered were deemed significant enough to require medical intervention.
Table 3. Summary of findings during preventive health evaluations in 1999
Categories
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Total
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Birds
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Mammals
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Herps
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Total # exams
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672
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284
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356
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32
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Complications
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40
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15 (5.3%)
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24 (6.7%)
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1 (3.1%)
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Prior clinical signs
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72
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8 (2.8%)
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60 (16.8%)
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4 (12.5%)
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Normal exam
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395
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148 (52.1%)
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225 (63.2%)
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22 (68.8%)
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Minor abnormalities
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235
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124 (43.7%)
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103 (28.9%)
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8 (25%)
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Major abnormalities
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42
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12 (4.2%)
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28 (7.9%)
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2 (6.2%)
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Manual restraint
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385
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186 (65.5%)
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174 (48.9%)
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25 (78.1%)
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Chemical restraint
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262
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98 (34.5%)
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157 (44.1%)
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7 (21.9%)
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Mechanical restrainta
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25
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0
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25 (7.0%)
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0
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aUse of chute/”squeeze”
The costs versus benefits of this program is difficult to assess at this early stage. Based on our guidelines, initial costs varied considerably by taxonomic groups. Higher initial costs are due to the comprehensive nature of the current guidelines. It is expected that these will change as the guidelines are updated to reflect those procedures that are most relevant to the long-term health of the collection. Representative costs for diagnostic tests and prophylactic treatments listed in the current guidelines are shown in Table 4. Use of mechanical restraint devices and husbandry training for medical procedures can be methods to reduce the costs of a health monitoring program.
Table 4. Representative costs for diagnostic testing and prophylactic treatments for selected taxonomic groups (based on guidelines)
Taxonomic group
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Diagnostic testing
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Prophylactic treatments
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Totala
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Antelope species
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Up to $72.50
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$22
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$94.50
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Psittacine species
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Up to $162.45
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$10
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$172.45
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Tortoise
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Up to $92.25
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$5
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$97.25
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Felid
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Up to $145.45
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$15
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$160.45
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aDoes not include cost of labor or chemical restraint
An example of a relative cost comparison for chemical versus mechanical restraint for health evaluation of an antelope herd is shown in Table 5.
Table 5. Estimated relative cost comparison of chemical versus mechanical restraint for health evaluation of an antelope herd (average of six animals)
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Chemical
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Mechanical
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Anesthetic drugs
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$25/animal
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$0 (does not include initial cost of equipment)
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Labor, veterinary staffa
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1 hour vet - $25/animal 1 hour tech - $15/animal Total: $40/animal
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20 minutes vet - $8.33/animal 20 minutes tech - $5/animal Total: $13.33/animal
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Labor, animal care staffa
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1 hour keeper (x 2–3 people) - $10/hour Total (ave): $25/animal
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20 minutes keeper (x 4–5 people) - $10/hour Total (ave): $15/animal
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Procedure timeb
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1 hour/animal
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20 minutes/animal
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Prep time, vet + tech
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1 hour total Total: $40/hour
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1 hour total Total: $40/hour
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Fixed costs (dx/rx)
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$94.50/animal
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$94.50/animal
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Total for six animals ($/animal)
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$1147 ($191.17/animal)
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$776.98 ($129.50/animal)
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aNumbers quoted are used for comparison only.
bProcedure time includes set-up, procedure, recovery or movement of animals.
As the collection becomes established, guidelines will be reviewed and upgraded annually to reflect collection and species-specific health concerns. Based on these preliminary results, the benefits of early detection and treatment, as well as establishing a collection database, appear to outweigh the risks associated with this program.
Acknowledgments
The authors wish to thank Kerri Bolling, Lidia Castro, Jenni Jenkins, Eileen McKee, and Carmen Peccie for excellent technical assistance in performing these procedures; the curators, zoological managers, and keepers of Disney’s Animal Kingdom for their support and participation in this program and overall partnership with the veterinary services staff.