Biosecurity in
amphibian collections
Richard Gibson1 and Kay Bradfield2
1Chester
Zoo and Amphibian Ark
2Durrell Wildlife Conservation Trust
The problem
Perhaps 500 species of threatened
amphibian require ex-situ
conservation, including intensively
managed captive populations to
produce animals for potential release
back into the wild.
Amphibian chytrid
• Batrachochytrium dendrobatidis – B.d.
• associated with amphibian
die-offs on every continent
(genetically uniform)
• unstoppable & untreatable
in the wild
• “the worst infectious disease ever recorded among
vertebrates in terms of the number of species
impacted, and its propensity to drive them to
extinction.”
Because chytrid fungus is a
major threat to most
amphibian species, protocols
for managing amphibians
ex situ must be modified to
take account of the need for
enhanced quarantine
and hygiene.
Furthermore, amphibian
Ark/Rescue/Supplementation populations
must be maintained as pure and ‘wild’ as
possible in order to be able to return them to
their natural habitats in the future. Facilities for
maintaining amphibian colonies of this nature
must therefore be ‘biosecure’.
What does ‘biosecurity’ really mean?
• Biosecurity - the protection of the environment and its
native species from exotic pathogens
• Biosecurity & ex-situ conservation facilities
– need to protect captive
spp. from pathogens
present in the external
environment (whether
facility is in-range or
out-of-range)
– need to protect native spp.
in external environment from
pathogens carried by captive
spp. (if captive spp. are being
held out-of-range)
How do we achieve biosecurity?
BIOSECURITY = RISK ASSESSMENT + RISK MINIMISATION
Risks are minimised through erecting and
maintaining appropriate barriers and routines.
• Multi-species facilities that house a geographically
diverse range of spp. or that are located outside the
range of species held, pose the greatest risks
• For conservation programmes you should retain
pathogens the species is exposed to in the wild, but
exclude others  the only way to do this is total
quarantine and isolation of projects, otherwise you
should not release animals into the wild.
The most successful amphibian
conservation programme to date?
Amphibian biosecurity is not just
about B. dendrobatidis
• There are numerous amphibian diseases we already
know about – what about the ones we haven’t
discovered yet?
• At least some of these will have had a long evolutionary
history as amphibian generalists, meaning that they may
infect other amphibian spp.
• As the natural host species are unlikely to exhibit signs
of infection, traditional quarantine measures (e.g. 30 –
90 day holding periods, health screening) will not detect
these pathogens.
Considerations for designing &
developing biosecure facilities
• Level of biosecurity required
– purpose of animals
– in-range vs. out-of-range
• Pathogen transfer/movement
– air?
– water
– substrates/live plants/‘furniture’/equipment
– wastes
– food animals (and their food)
– pests
– the animals themselves
– people
Considerations for designing &
developing biosecure facilities cont…
• Treatment /disposal of waste from facility
– Water
e.g. holding tanks & chlorine injection
– other waste (faeces, substrates, ‘furniture’,
equipment, uneaten food, gloves, disposable
gowns, etc.)
e.g. double bag as clinical
waste & incinerate
Considerations for developing biosecure &
quarantine working protocols
• Restrict access to essential staff only
• Staff must be trustworthy & reliable
• Minimise keeper access to biosecure facilities
& enclosures within them
– every time a facility / enclosure is accessed
there is the potential for biosecurity to be
breached  minimising keeper access
allows greater isolation (and therefore
protection) of animals
Considerations for developing biosecure /
quarantine working protocols cont…
• Protective clothing
– footwear
• dedicated boots
– gowns/overalls
• disposable vs. washable
– gloves
• must be worn with all amphibians at all
times!
• put on/remove in a sterile fashion!
• Dedicated instruments/equipment for each
enclosure/species
Considerations for developing biosecure /
quarantine working protocols cont…
• Always follow the same service order
- rooms/buildings
- within rooms/buildings
• Disinfection of equipment & enclosures
- disinfectant(s) used
- concentration & contact time
- need to remove organic matter
• Maximise automation
- spray systems
- filtration systems
- food funnels
The AArk’s role is to help the zoo/aquarium
community save as many amphibian
species as possible by:
•
•
•
•
•
•
Providing global coordination
Technical guidance
Training
Linkage to other IUCN groups
Communications
Guiding publicity and capital campaigns
Basic
Specimens maintained ex situ for Educational* purposes with no requirement for research and no prospect of release to the wild.
BIOSECURITY
 Separate footwear per room and/or footbaths at entry/exit.
 Treatment/decontamination of all waste water from enclosures and rooms housing amphibians prior to discharge/disposal (addition of
household bleach at ratio 1:10 by volume).
 Incineration (or disinfection by means of suitable chemicals, heating to 70°C for 25mins, or complete desiccation) of all amphibian enclosure
waste – soil, leaves, plants, furnishings, food items, faeces, bodies (after post-mortem examination).
 Escape-proof housing of a size appropriate for species.
 Pest-proof housing (rodents, cockroaches, ants, etc) to prevent pathogen transfer, predation of amphibians, and escape of food insects.
 Water free of pathogens and chemical contaminants.
HUSBANDRY
 Regular water changes – automated or manual.
 Appropriate cage furnishings wherever necessary.
 Exposure to natural light (or good artificial equivalent) if exposure is normal in natural history of the species.
 Appropriate temperature/humidity for natural history of the species.
 Appropriate food, dependent on species – with supplementation (vitamin/mineral).
Intermediate
Specimens maintained ex situ for Conservation Research* purposes with no prospect of release to the wild.
All Basic standards, but also:
BIOSECURITY
 Individual instruments (tongs, nets, bowls, tanks, pumps, filters etc) per enclosure and/or species.
 Change gloves (non-powdered) for each enclosure.
 Design of enclosure should minimize keeper/animal contact.
 Maximize use of automation in water quality maintenance/watering.
 Maintain a consistent/directional flow of husbandry routine – from low risk and high importance
species/individuals to high risk and lower importance species/individuals.
HUSBANDRY
 Climatic conditions (lighting, photoperiod, temperature, rainfall, humidity, etc) should follow the natural cycle for
the species and be automated wherever possible.
 Highest level of record-keeping.
Advanced
Specimens maintained ex situ for conservation breeding purposes (Ark/Rescue/Supplementation)* with the
ultimate expectation of release to the wild.
All Basic and Intermediate standards, but also:
BIOSECURITY
 One species or local assemblage of species per room/unit – a state of permanent quarantine.
 Separate uniforms/overalls per room (stays in room unless disposable).
 Food coming from known and trusted source; 3-month period of familiarization with natural food types
recommended prior to any release.
 Pre-release, monitor condition of specimens to determine fitness for release – thorough health screening
including; regular and frequent PCR screening for chytrid fungus over several months; screening for Ranavirus;
regular bacteriological and parasitological screening; and thorough necropsy and histological examination of
deceased animals and a representative subset of the intended release animals – see Pessier, A. P. (In press):
Management of disease as a threat to amphibian conservation. International Zoo Yearbook, 42, for a
comprehensive overview of amphibian health screening needs.
Room 2
(north side)
A re-discovered Costa Rican highland species
The future
green-eyed frog Lithobates vibicaria
Training
ACH – Jersey, 2008
• Amphibian Conservation Husbandry 2008 (ACH)
• Duration: 11 days
• Participants: 21 ex-situ amphibian
conservationists from 11 European countries
• Course content:
Module 1: Amphibian biodiversity and change
Module 2: Captive facility design and construction
Module 3: Breeding and managing populations
Module 4: Managing animal health in captivity
Measuring UV light from
different light sources
Spawned by the ACH
•
•
•
•
•
Thoiry, France – March 2009
Barcelona, Spain – Feb 2009
Reaseheath, UK – 2009
Nordens Ark, Sweden, Feb 2009
Rotterdam/Antwerp/Amsterdam,
Netherlands/Belgium – Nov 2008
• Riga, Latvia (incl Russian zoos) – Oct 2008
• Zoo/private, Germany – Nov 2008
• Lisbon, Portugal – June 2008
Biosecurity & ‘educational’ animals
While we may not be (as) worried about transmitting
pathogens to animals held purely for educational
purposes, we do need to be concerned about the
possibility of transmitting pathogens from these animals to
the local environment
– gloves
– footwear/footbaths
– treatment of waste water
– incineration of other waste
What about…
•
•
•
•
•
•
Universities
Laboratories
Schools
Pet shops
Pet keepers
Frog farms
AARK plans to write Basic Biosecurity
for Amphibian Keepers document for
dispersal to these sectors of the
amphibian-keeping community
What about?