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Research Proposal

Background

Norfolk is an external territory of the Commonwealth of . In 2011, the government and the Australian government signed the Norfolk Island roadmap to undertake activities to move Norfolk Island towards becoming an economically sustainable community (Norfolk Island Government, 2011). One of the recommendations of the roadmap was to undertake actions that would allow travel between the Australian and Norfolk Island to be undertaken as domestic travel. To do this, Norfolk Island would need to be brought within the Australian Quarantine Barrier.

Prior to Norfolk Island being brought within the quarantine barrier, the Australian government would need to ensure that Norfolk Island did not present a threat to Australia’s agricultural industries or environment. To examine whether Norfolk Island presents any such threat, Regional Australia (within the Department of Infrastructure and Regional Development) engaged the Department of to undertake an animal and plant health survey of Norfolk Island (East, 2014).

Bovine tuberculosis is a serious disease of and is notifiable to the World Organisation for Animal Health if a country finds evidence of infection (OIE, 214). After a long and expensive campaign of eradication, Australia declared freedom from infection with bovine tuberculosis in 1997 and has since maintained that status (Cousins and Roberts, 2006). Detection of bovine tuberculosis in Australia would lead to a sharp contraction in exports in live cattle and beef as tuberculosis- sensitive markets blocked . Our trade in cattle and cattle products exceeds $6.8 billion per annum (ABARES, 2014); this would have significant impacts on the Australian economy. Mycobacterium avium infects many species of (Smit et al., 1987; Dvorska et al., 2006) and infection can transfer to mammals including (Montali et al., 1998) and cattle if they come into contact with infected birds in the environment. Although infection in cattle is usually asymptomatic, it is important because it interferes with the tuberculin test used to identify cattle infected with bovine tuberculosis (Simpson, 2002).

Over the past forty years, cattle on Norfolk Island have, on several occasions, have reacted to tuberculosis testing and have been subsequently seized and compulsorily slaughtered. Each time, the question of whether the test result is due to infection with bovine tuberculosis or with avian tuberculosis has been raised without resolution. Former Chief Veterinary Officer of New South Wales, Helen Scott-Orr has advised that Norfolk Island was included in the Australian brucellosis and tuberculosis eradication campaign in the 1980s and 1990s and was declared provisionally free of tuberculosis. However, in September 2013, a team from the Department of Agriculture conducted tuberculosis skin tests on 155 cattle on Norfolk Island. The test involves simultaneous sub- cutaneous injections with both avian and bovine tuberculosis preparations. The final tuberculosis status is determined by the relative response to the two injections (delayed type hypersensitivity visualised as a swelling/lump at the injection site). Five cattle returned suspect tests (‘reactors’) indicating possible infection with tuberculosis. This was thought most likely due to be infection with avian tuberculosis Infection with avian tuberculosis in cattle requires an avian host in the environment to maintain presence of the bacterium in the environment. During the September 2013 study and a follow-up study in April 2014, 35 feral chickens from the island’s population were euthanased and autopsied but no evidence of infection with avian tuberculosis was observed.

During the April 2014 visit, conversations with a past Norfolk Island stock inspector, James Partridge, indicated that a NSW government vet had autopsied a range of species in the late 1980’s and had only found evidence of avian TB infection in mutton birds (Puffinus pacificus = Ardenna pacifica). Unfortunately, no records of that investigation have survived in either the NSW Department of Primary Industries or the Norfolk Island government archives. Of the two possible vets who could have conducted the studies, one (Les Valentine) was traced through the NSW Veterinary Registration Board but Dr Valentine is advanced in years and has not responded to correspondence requesting his assistance in confirming these verbal reports. The other vet (Rob North) could not be traced.

Rationale for study

Definitive demonstration of an avian species as the host that maintains avian tuberculosis in the Norfolk Island environment would provide crucial evidence that finding ‘reactors’ to tuberculosis testing in cattle on Norfolk Island is due to the presence of avian tuberculosis in the environment. This would not only provide a rationale for presence of the ‘reactors’, but when coupled with the known history of import restrictions for animals entering Norfolk Island, would provide solid evidence to support the case that Norfolk Island (and thus Australia) is free from bovine tuberculosis. Thus, in the future, any ‘reactors’ would not trigger a disease alarm or impact on Australia’s trade in cattle and beef.

Study design

A maximum of 30 mutton birds will be captured by netting under the direct supervision of ####, the Conservator of Norfolk Island. #### is also an experienced bird bander registered with the Department of Environment and has extensive experience in the capture of seabirds by netting. The birds will be euthanized by cervical dislocation. Advice from six State government veterinarians responsible for managing animal welfare is that cervical dislocation is an appropriate method of rapidly killing birds of this size while minimising stress to the birds. The birds will then be autopsied and their liver, spleen and intestines inspected for clinical evidence of infection with avian tuberculosis. Any suspect findings (granulomas, nodules, etc.) will be further investigated by preservation of samples and submission to the New South Wales government laboratory at the Elizabeth Macarthur Agricultural Institute in Camden for examination by histopathology.

We have been approached by CSIRO in Hobart who is interested in ingestion of environmental contaminants such as plastic by seabirds. We are proposing to retain the gut contents of the mutton birds that we autopsy, preserve them and forward them to #### for examination. Additionally samples of feather quills would be obtained from the birds by the conservator of Norfolk Island to enable molecular analysis. This will allow three separate projects to be conducted from the one set of birds trapped. Impact on the mutton bird colony will be minimised by trapping the birds in groups of ten. If autopsy of the first group reveals conclusive evidence of infection with avian tuberculosis, the second and third groups will not need to be collected.

Potential benefits to the target species

If infection with avian tuberculosis is confirmed in the mutton birds, a rationale would exist for establishment of fencing to separate free wandering cattle in the Norfolk Island road herd from the nesting areas used by the mutton birds. Whilst not planned as part of this project, such fencing would provide a safeguard for the integrity of the nesting environment of the mutton birds.

Personnel

#### – Norfolk Island Conservator and registered bird bander. #### has extensive experience in the capture, handling, banding and release of several species of sea birds including the target species for this study. #### will be responsible for the trapping of birds by netting.

#### – veterinarian with 30+ years experience with the Victorian Department of Primary Industries, the Hong Kong government and the Australian Department of Agriculture. #### experience includes veterinary investigations in a range of remote locations including -New Guinea, and Norfolk Island. #### will euthanase the birds and conduct the autopsies.

#### – Scientist and epidemiologist with 30+ years experience working with livestock. #### is managing the animal health survey of Norfolk Island and will assist in autopsies and sample preservation.

References ABARES (2014) Agricultural commodities: June quarter 2014. http://daff.gov.au/abares/publications (Accessed 31 July 2014)

Cousins, D.V. and Roberts, J.L. (2006) Australia's campaign to eradicate bovine tuberculosis: the battle for freedom and beyond. Tuberculosis 81:5–15.

Dvorska, L., Matlova, L., Ayele, W.Y., Fischer, O.A., Amemori, T., Weston, R.T., Alvarez, J., Beran, V., Moravkova, M. and Pavlik, I. (2007) Avian tuberculosis in naturally infected captive water birds of the Ardeideae and Threskiornithidae families studied by serotyping, IS901 RFLP typing, and virulence for poultry Veterinary Microbiology 119:366–374.

East, I.J. (2014) Norfolk Island Quarantine Survey. Animal Health Surveillance Quarterly Report, Issue 4, p 6, Apr 2014

Montali, R.J., Bush, M., Cromie, R., Holland, S.M., Maslow, J.N., Worley, M., Witebsky, F.G. and Phillips, T.M. (1998) Primary Mycobacterium avium Complex Infections Correlate with Lowered Cellular Immune Reactivity in Matschie's Tree Kangaroos (Dendrolagus matschiei) The Journal of Infectious Diseases 178:1719-1725.

Norfolk Island Government (2011) Norfolk Island Road Map. http://www.info.gov.nf/news/Information/Norfolk%20Island%20Road%20Map%20- %202%20March%202011.pdf (Accessed 31 July 2014) OIE (2014) OIE-Listed diseases, infections and infestations in force in 2014. http://www.oie.int/animal-health-in-the-world/oie-listed-diseases-2014/ (Accessed 31 July 2014)

Simpson, V.R. (2002) Wild Animals as Reservoirs of Infectious Diseases in the UK. The Veterinary Journal 163:128-146

Smit, T., Eger, A., Haagsma, J. and Bakhuizen, T. (1987) Avian Tuberculosis in Wild Birds in the . Journal of Wildlife Diseases 23:485-487.