AVA: Antidote for Toxin para-aminopropiophenone (PAPP)

Please note the following information on a new toxin being released for wild dog and fox management in Australia, as it may result in off-target intoxication of domestic pets. The toxin is para-aminopropiophenone (PAPP) which induces methaemoglobinemia following ingestion. There is an antidote (IV methylene blue) which needs to be administered promptly. This may impact practitioners in peri-urban and rural areas where wild dog and fox control is being undertaken.

Below is some general information, and more detail can be found in the booklet

Kind regards,
Melanie Latter

Dr Melanie Latter BVSc Hons1, GCPA, MANZCVS, PhD | Veterinary Affairs Manager
Australian Veterinary Association
AMA House, 42 Macquarie St, Barton ACT 2600
PO Box 4257, Kingston ACT, 2604
T. 02 6273 0064  |  F. 02 6273 0237  |  E. melanie.latter@ava.com.au   |  W. www.ava.com.au

 

Baits containing PAPP released for wild dog and fox control – with potential consequences for domestic pets.

A new toxin for wild dog and fox management is being released in Australia.  Veterinarians may be presented with cases of off-target poisoning of domestic pets, so need to be aware of the mode of action of the toxin and its antidote in order to attempt management of these cases.

Known as DOGABAIT and FOXECUTE®, the new baits contain the chemical para-aminopropiophenone (or ‘PAPP’), which induces methaemoglobinemia following ingestion.  Products containing PAPP have been approved for use by the APVMA, and are manufactured and distributed by Animal Control Technologies Australia (ACTA). 

PAPP is considered to be a humane toxin, and has the potential to replace 1080 use in many situations.  It has an additional advantage in that it has an antidote, Methylene Blue.  Limited trials show that, if an animal is administered the antidote relatively quickly by IV injection (likely within one hour of bait exposure), it can recover with no long-term effect. At this stage, this antidote can only be administered by a veterinarian.

ACTA have prepared a tailored briefing note on PAPP baits specifically for veterinarians (attached)

A summary, provided by the Invasive Animals CRC, follows.

 

What is PAPP and how does it work?

Para-aminopropiophenone (or ‘PAPP’) is the active ingredient used in new toxic baits developed for the broad-scale management of canids. Once ingested, PAPP works by converting normal haemoglobin to methaemoglobin. Clinical signs include lethargy, ataxia, unresponsiveness, unconsciousness and death.  Limited studies suggest that animals receiving a sub-lethal dose can fully recover without lasting complications.  PAPP baits are scheduled Restricted S7.

 

Is PAPP safe for domestic and working dogs?

No. Since PAPP is lethal to wild dogs and foxes, it is also highly toxic to all domestic and working dogs, depending on the dose ingested. The mode of action is fast and symptoms of methaemoglobinemia are diagnostic.  The carefully considered PAPP dose in fox baits mean that an average-sized working dog will be less affected after eating one fox bait, but treatment should be sought immediately. Due to the higher dose in wild dog baits, if a domestic or working dog eats just one dog bait, it will die within 1-2 hours if there is no treatment with antidote. This means that the use of PAPP baits will require careful consideration of potential risk to pets, working dogs and other non-target animals.

 

Is there an antidote for PAPP?

Yes. The chemical methylene blue converts methaemoglobin back to haemoglobin and immediately reverses the effects of PAPP poisoning, with recovery usually occurring within 1 hour, based on limited studies. At present, methylene blue can only be purchased and administered by a veterinarian.

 

Can an animal killed with PAPP be distinguished from one killed by 1080?

Yes. Bright orange plastic marker beads incorporated into PAPP baits can be found in the stomach of affected animals and even in the decayed carcass. Similar red marker beads are incorporated into ACTA manufactured 1080 baits.  Animals with PAPP poisoning also display grey-blue gums and tongue, caused by the change in blood colour from red to brown.

 

Can PAPP harm other animals?

Members of the dog and cat families are highly susceptible to PAPP compared with other species, and this is due to the unique way that they metabolise PAPP. In Australia, cats, foxes, and wild dogs are the animals most susceptible to PAPP; however PAPP will only be available for wild dog and fox control in manufactured baits. The materials used to make these baits have shown to be less palatable to herbivores. PAPP is known to affect some native non-target animals like goannas and for this reason aerial deployment of FOXECUTE and DOGABAIT has not been approved.

 

Where can I find more information regarding PAPP?

For more online information visit the Invasive Animals CRC PestSmart webpage on PAPP at www.pestsmart.org.au/papp

 

Methylene Blue is distributed by Phebra
Contact is Poonam Kamboj,Pharmacovigilance & Medical Information Manager,
P:  +61 (0)2 9420 9199 (ext 926)  
M: +61 (0) 438 275 827

This news article was published on 09 September 2019.