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Secretary’s ACEC guidance for reporting Unexpected Adverse Events when caring for and using animals for scientific purposes

The NSW Animal Research legislation requires investigators who have projects approved by the Secretary’s Animal Care and Ethics Committee (ACEC) to promptly notify the ACEC of any unexpected adverse events that have a negative impact on animal wellbeing that have occurred in animals used in projects that the ACEC has approved

What is an adverse event?

The Australian code for the care and use of animals for scientific purposes 8th Edition 2013 (the Code) defines an 'adverse event' as any event that has a negative impact on the wellbeing of an animal.

What is an unexpected adverse event?

The Code defines an 'unexpected adverse event' as an event that may have a negative impact on the wellbeing of animals and was not foreshadowed in the approved project or activity.  

An unexpected adverse event may result from different causes, including but not limited to:

  • death of or illness in an animal, or group of animals, that was not expected,
  • adverse effects following a procedure or treatment that was not expected,
  • adverse effects in a larger number of animals than predicted during the planning of the project or activity, based on the number of animals actually used, not the number approved for the study,
  • a greater level of pain or distress than was predicted in the planning of the project or activity,
  • power failures, inclement weather, emergency situation or other factors external to the project or activity that have a negative impact on the welfare of the animals.

Please also refer to the section at the end of this page regarding notifiable animal diseases and biosecurity events to ensure you understand when and how to report under the Animal Biosecurity Act 2015.

Difference between expected and unexpected adverse events

The difference between an expected ‘adverse event’ and an ‘unexpected adverse event’ is that an unexpected adverse event is a negative impact on the wellbeing of animals and was not foreshadowed in the application for the approved project or activity.

Basically, unexpected adverse events are unanticipated or atypical incidents with a negative impact on the wellbeing of research animals which are currently held under an Animal Research Authority that occur as a result of project procedures or manipulation, trapping, routine husbandry or diseases and these were not anticipated and described in the project application for ACEC approval.

What should you do when planning your project and writing your project application form to foreshadow expected adverse events?

Every project has potential for things to not work out as planned. Most projects also have some predictable negative impacts or expected adverse events that need to be considered when planning the project and writing the ACEC project application.

During the project preparation stage, you need to think realistically and honestly about what might go wrong and assess/estimate the risk (likelihood and consequence) of that occurring and how it could be mitigated.

When you’re writing your application, identify the things that you know might go wrong and describe the mitigating actions you will take to try and prevent or minimise them. You should also include the anticipated incidence at which they may occur, despite mitigations, based on experience, literature review and/or recognised industry averages. This will give the ACEC a realistic expectation of the things that may go wrong and they can decide whether this is acceptable, or not, when considering your application for approval.

If an adverse event described in your project application is approved by the ACEC as an acceptable level of risk, then if such an event occurs, within the parameters of the ACEC approval, it does not need to be reported to the ACEC. If the adverse event falls outside of the parameters approved or if the mitigating actions approved by the ACEC have not been implemented, then the adverse event is unexpected and would need to be reported to the ACEC.

For example, in production animals, there will be a recognised level of calf, lamb or piglet mortality. If this is included and cited in your application as a recognised industry average and approved by the ACEC, then this is an expected event, to the approved level and anything above that level will need to be reported as unexpected. Similarly, if you anticipate an industry acknowledged and accepted death/attrition rate during wildlife trapping, this can be cited in your application for ACEC review.

Other examples of adverse events may include:

  • fauna injury or death in traps during a survey
  • the death under anaesthetic or during surgery of a well animal
  • animal breaking its leg when yarded for procedures
  • illness in or injury to animal as a result of project procedures
  • cancer developing on an animal which needs to be treated.

Note that reporting of unexpected adverse events is required even when the cause of death of a research animal appears to be external to and/or outside of the control of approved research activities. An example of this is when a research animal wearing a tracking device is preyed upon and killed or injured.

Secretary's ACEC’s expectations

The Secretary’s ACEC understands that unexpected adverse events may occur despite every attempt to mitigate their occurrence. We believe unintentional and unexpected are the same thing. The ACEC will use a ‘common sense approach’ when reviewing unexpected adverse events.

The ACEC expects the Code clauses 2.4.18(ix) and 3.1.25 to be followed:

Investigators must take “prompt action, including alleviation of pain and distress and promptly notifying the AEC, in response to unexpected adverse events and emergencies, in accordance with institutional and AEC policies and procedures. Alleviating pain and distress must take precedence over an individual animal reaching the planned endpoint of the project, or the continuation or completion of the project.  If necessary, animals must be killed humanely without delay.” (2.4.18(ix))

“When an animal dies unexpectedly, or is humanely killed due to unforeseen complications, a necropsy should be performed by a competent person.” (3.1.25)

When to do a Post-mortem Exam?

When any animal that dies unexpectedly or is euthanased due to unforeseen complications or unknown circumstances, it is an expectation of the Code that a post-mortem examination be performed by a person competent to determine the cause of death. Even if you think you know the cause of death, an examination can be useful to make sure that there was no underlying pathology. This could be a health problem in the animal that was not detected prior to the procedure and by investigating this you will be helping make sure that no other animals have similar problems and an appropriate and timely intervention is made. The results of the post-mortem and any follow-up pathology performed, will form part of the report to the ACEC.

For wildlife surveys specifically, the ACEC accepts that post-mortem examinations are not always possible when working remotely and are not required where the cause of death is immediately obvious, for example wildlife predation or injury while in a trap, male antechinus death in spring after breeding or collision with a motor vehicle. However, if the researcher has developed new techniques after the event to prevent this type of event occurring again, the AEC would like to be informed of this.

The Secretary’s ACEC expects post-mortems to be conducted:

  • if the death was not foreshadowed in the approved project or activity
  • if the death cannot be attributed to natural or other known causes
  • when no cause is readily apparent, and the health of more animals is under threat
  • when there is any possible public health implication.

In summary, if the death was not foreshadowed in the approved project or activity and cannot be reasonably attributed to natural or other known causes, a post-mortem should be performed by a person with appropriate experience and competent to determine the cause of death.

Ideally post mortems should be performed by veterinarians as they are able to determine the human, animal and environmental safety risks of conducting post mortems on a case by case basis (such as in suspect cases of Anthrax or Hendra when a post mortem should not be performed) as well as being qualified to make a diagnosis and decisions regarding sample collection, onsite testing and submission to a laboratory.

Information about laboratory submissions is available at:

Specific post mortem guides are available electronically from agric.wa.gov.au:

Who should you report to?

When unexpected adverse events occur, the problem should be reported to the Principal Investigator, if they were not present, and other staff involved in the care and welfare of animals in the project. The ACEC should be notified by way of an Unexpected Adverse Event (UAE) Report. In the case of livestock or companion animal projects, local staff will want to know about problems as soon as possible so that they can address any immediate animal welfare issues and help prevent further adverse events from happening. This can only happen with early and accurate reporting.

Timeframe for reporting an unexpected adverse event to the ACEC

Reporting of an unexpected adverse event should be carried out as soon as practicable to the ACEC, ideally within 72 hours of the event. This reporting is done by emailing a completed Unexpected Adverse Event (UAE) form to secretary.acec@dpi.nsw.gov.au. The UAE Report template can be found on the Secretary’s ACEC website under the Secretary’s ACEC Forms heading.

What you should include in the report?

Follow the UAE Report Form template (DOC, 212.5 KB). This should help you provide the information required by the ACEC. The completed report should tell the ACEC what, when and why the event happened, how the event was handled and what will be done to prevent it occurring again. If a post-mortem was conducted, the post-mortem report should be provided as soon as it becomes available.

What AECs are required to do when an unexpected adverse event is reported

The Code requires that the Secretary's ACEC takes appropriate action in response to unexpected adverse events to ensure that animal wellbeing is not compromised, the issue is addressed promptly, and activities that have the potential to adversely affect animal wellbeing cease immediately. The ACEC will advise the Principal Investigator of any action required when the UAE Report has been fully considered.

Lessons Learnt

The ACEC recognises that unintended animal deaths sometimes occur during a study. It is important to report to the ACEC unexpected or unusual deaths of target and non-target animals, including pouch young, as well as any other unexpected adverse events that may compromise animal welfare. There may be other researchers having similar problems, or techniques developed which could reduce such losses. Reporting deaths may help you and other researchers develop better procedures.

The reporting requirement should not be seen as punitive, but rather the best way to ensure that future problems are prevented. One of the most important things to come out of this process is to really think about what went wrong and what you will do differently to address the problem, including what further steps were or could be put in place to prevent or further reduce the risk of a repeat event occurring.

If there are changes needed to your procedures to address the unexpected adverse event, you will need to submit an application to modify/ vary the application for these changes to be approved by the ACEC before procedural modifications can be enacted. Templates for project modification applications (DOCX, 196.21 KB) can be found on the Secretary’s ACEC website under the Secretary’s ACEC Forms heading

Reporting notifiable animal diseases and biosecurity events under the Biosecurity Act 2015

Notifiable animal diseases

There are two categories of notifiable animal diseases under the Biosecurity Act 2015.

Emergency animal diseases are listed as prohibited matter under the legislation.  These diseases include Hendra, anthrax and highly pathogenic avian influenza, plus exotic animal diseases such as rabies, equine influenza, african swine fever and foot and mouth disease. These diseases must be reported immediately and verbally to an authorised officer by phoning the Emergency Animal Diseases Watch Hotline on 1800 675 888 (24 hour service, every day of the year), or, during business hours, by phoning Local Land Services on 1300 795 299.

The second category of notifiable diseases are the endemic notifiable animal diseases. These include diseases such as footrot, Johne’s disease and cattle tick. These diseases must be reported to an authorised officer within one working day, by phoning Local Land Services on 1300 795 299 or DPI on 1800 680 244.

A full list of notifiable animal diseases and how to report can be found at Notifiable pest and diseases of animals in NSW.

Biosecurity events

Biosecurity events must be reported immediately and verbally to an authorised officer in the same manner as reporting emergency animal diseases.

Biosecurity events include:

  • an unusually high number of sick or dead animals,
  • a sudden or unexplained fall in production relating to animals,
  • the appearance of unusual clinical signs, including, but not limited to, unusual neurological signs in animals,
  • the appearance of ulcers or blisters on the mouth or feet of ruminants or pigs.


The contribution of Prof Gail Anderson, via the ANZCCART ComPass online training course for AEC members and research animal users, to the development of this guide is gratefully acknowledged.