RESEARCH will continue into a farmer-friendly domestic dog antidote for new fox and wild dog baits containing para-amino propiophenone or PAPP – the first new predator toxin in 50 years.
The new schedule Restricted S7 baits — FOXECUTE® and DOGABAIT® — were launched this week after 11 years of research and development by Animal Control Technologies Australia Pty Ltd, Australian Wool Innovation and the Australian government through the Invasive Animals CRC.
The PAPP baits have the unique feature of having an effective methylene blue-based antidote, but which currently has to be administered by a veterinarian within a short time after an accidental poisoning.
PAPP and 1080 are now the only two poisons available for wild dog and fox control in Australia, but no antidote is available for 1080 poisoning, though dogs can be saved with early appropriate action.
The RSPCA has recognised the fast-acting PAPP baits as more humane than the main dog and fox poison 1080, but they can only be supplied or used by an authorised person. Aerial baiting is not allowed due to a lack of target-specificity and they cannot be used in peri-urban areas.
PAPP is highly toxic to wild dogs, domestic dogs, foxes and cats, and also toxic to marsupial carnivores and can pose a risk to goannas, bandicoots and some birds, including ducks. The new baits could retail for 2-3 times the cost of 1080, depending on state access methods, retailer margin and pack size. Geographic use restrictions are expected to be similar to those for 1080.
Further research to develop an on-farm antidote
Leader of the Blue Healer PAPP antidote project at the Invasive Animals CRC Simon Humphrys said the PAPP antidote was not toxic in therapeutic doses, “but you can overdose a dog with the antidote as well.”
“We know what the toxic doses are and we’ve been educating veterinarians as to the contraindications; so what not to go over as far a dose to not run the risk of complications.”
Mr Humphrys said research would continue into achieving an antidote that is able to be used by farmers without needing a veterinarian.
“I would hope within the next two years we would have that through the registration system, but that really depends on us finding a route of administration that’s safe and effective; that’s the research that needs to be done over the next 12 months,” he said.
“We’ve been working on that for the past three years and we just can’t find anything that is effective enough via the oral route of administration or via the rectal route.
“Intramuscularly or subcutaneously with methylene blue is really difficult because it actually causes necrotic lesions, so they are not options for us.”
Mr Humphrys said the antidote’s current formulation and approved label required it to be administered only by injection directly into a vein.
“Training dog owners and farmers to administer the antidote to dogs by injection into a vein could be an option under certain circumstances but we think there’ll be better ways to achieve a practical and effective outcome for dog owners and farmers.”
Although methylene blue is available through chemical suppliers there is only one antidote product approved for sale by the Australian Pesticides and Veterinary Medicines Authority and the approval conditions restricts its sale to and use by vets.
Mr Humphrys said there is only one company in Australia that manufactures a sterile methylene blue product that satisfied the standards of Good Manufacturing Practice.
“Replicating this manufacture would take hundreds of thousands if not millions of dollars so the CRC has opted to collaborate with Phebra in Sydney to achieve a nationally registered product that vets can buy and use safely and effectively and also to research and potentially develop a product that dog owners can use.
“The CRC has also engaged with the Australian Veterinary Association to gain their endorsement of treatment recommendations and through this process we’re aiming to have an approved label that’s as flexible as is practically safe given the risk of non-treatment is the death of the dog.”
‘Methylene Blue Injection’ is the name of the approved product that is available for vets to purchase now, he said.
“We are working with Phebra to apply for a label change, so that it can be called Blue Healer.
“It may be that the dog owner product is called Blue Healer and the currently available vet-only product name is left as is to distinguish the two.”
PAPP antidote story was “oversold”
ACTA managing director Professor Linton Staples said there were still concerns about the toxicity of the PAPP antidote in untrained hands.
“If an untrained or amateur person tries to administer the antidote, there is a risk of giving too much and causing toxicity from the antidote which is powerful enough to kill the animal.
“Unfortunately there is a very narrow window between using the antidote to overcome the PAPP and killing the animal from the antidote, plus it only works by intravenous administration,” he said.
“They have tried other routes, but you can’t give it as a suppository, a tablet or as a drench.
“The poison works quite quickly and the symptom of the poison is the animal lies down and has a snooze, falls asleep and dies,” Professor Staples said.
“So a lot of people would misdiagnose the animal having taken a bait with it taking an afternoon snooze.”
Professor Staples said at this stage the PAPP antidote can only be administered by a veterinarian and it is impractical for farmers to expect to do this currently.
“But we are all looking at that as a priority and would like to achieve it.
“That’s what is needed here, something the farmer can use,” he said.
“We all want that, but at the moment technically, it’s not looking too likely.”
Professor Staples said ACTA had been under the impression that the antidote was “cheap, easy to administer and worked a treat, but now we are finding out that it is a bit more complicated.” He recognised that PAPP might not be widely used because of its cost and antidote issues, and the continued efficacy of 1080.
ACTA had hoped PAPP would be scheduled as an S7 poison and be more available to people in the peri-urban fringe, rather than a Restricted S7 in the same category and with the same access provisions as 1080. PAPP’s antidote story was “oversold”, he said.
Professor Staples said in pastoral areas he would still advise landholders use 1080 baits because they are cheaper.
“PAPP works, but at an extra cost to achieve the same end-point in the pastoral country which should still stick with 1080 baits on the large scale.”
PAPP not a “silver bullet”
Chair of the National Wild Dog Action Plan stakeholder group Geoff Power said the PAPP bait for wild dogs was just another tool and was not a “silver bullet”, because of the restriction of its use to certain areas, its extra cost and the antidote issues.
“It could be handy, especially in inside areas where a working dog might take a PAPP bait and if the antidote is able to be applied within a certain time you would probably save the working dog.
“It certainly wouldn’t replace 1080, 1080 is still the main bait we will be using.”
Mr Power said the use of the PAPP baits would be restricted by the inability to distribute baits from the air. Landholders would still rely on cluster and dog fence maintenance in SA, NSW and Queensland, and collaboration with neighbours on baiting and other control measures for wild dog control, he said.
“Baiting with 1080 is still important and trapping cunning dogs that don’t take baits – it’s not replacing anything, it is just an add-on to what we’ve already got.”
Mr Power said if PAPP users had a good relationship with their veterinarian it would make sense for the landholders to be able to administer the antidote.
“I can’t see why we can’t do that with the PAPP antidote.
“If it is half an hour, who can get to a vet in half an hour?” he said.
“I don’t think it will be used widely at this stage.
“Firstly, there is the cost of it and secondly, the great advantage of being able to apply an antidote isn’t available unless you can actually apply it yourself.”
Farmer access to PAPP antidote “the way to go”
Queensland sheep and cattle producer and member of the Southern Downs Wild Dog Advisory Group Ben Cory said the state’s livestock producers were hoping PAPP would help with wild dog control as a more fast-acting humane poison. Farmer access to the PAPP antidote would “be the way to go in the long run”, he said.
In pastoral areas there would be insufficient time to get a poisoned dog to a veterinarian and owners also had to be vigilant to notice if their dog took a PAPP bait, Mr Cory said.
Field trials show ACTA baits work well
Professor Staples said through extensive field trials around the country, the new baits had proven to be highly effective and the PAPP chemical had been shown to be absorbed quickly from specially designed wild dog and fox baits developed by ACTA.
AWI On Farm Program manager Ian Evans said he is extremely pleased to see that this major R&D investment has resulted in an ‘on the ground’ product that farmers and land managers could now use in addition to other wild dog and fox control measures.
“Wild dogs and foxes cause significant financial hardship not only to wool producers but to all livestock producers in Australia.
“Losses can exceed hundreds of millions of dollars to the agricultural industry and AWI is committed to supporting innovative R&D projects in this area.”
National wild dog facilitator for the IACRC, Greg Mifsud, emphasised that the new baits will complement existing control techniques, such as 1080 baits, trapping and shooting, to manage wild dogs and foxes within Australia.
“These new baits will enable a more comprehensive regional management approach to wild dog and fox management within Australia.
“We will always emphasise an integrated and coordinated approach to wild dog and fox control and there is certainly no one silver bullet to solve the problem but we welcome any new tools within the toolbox.”
Superfine wool grower and IACRC chair Helen Cathles said without the support of the multiple partners involved in the PAPP project all pushing for an outcome to help the agricultural industry, the reality of a new product would have never eventuated.
“We are proud that the Invasive Animals CRC has and will continue to play a major role in facilitating this collaboration.”
PAPP bait products are available for sale to approved users and come under the same restrictions as purchasing and using 1080 baits. Use of the PAPP bait products differs between states and territories, so checking with local authorities before use is recommended.
For more information on purchasing the products visit www.animalcontrol.com.au
For more information on the best practice wild dog control visit www.pestsmart.org.au/pest-animal-species/wild-dog/