PAPP is highly toxic to dogs and foxes but much less toxic to most other species (on a per kg liveweight basis). However, there are some species that are more susceptible to PAPP than to 1080. For example,1080 has very low toxicity for goannas but they are vulnerable to PAPP. For this reason the label recommends that PAPP baits are not used when goannas are most active (summer) and that PAPP baits are not approved for aerial application.
Quolls and bandicoots could also be vulnerable to baits containing PAPP, but studies have shown low uptake of buried manufactured baits by these native species. Independent environmental authorities have assessed that even if some individuals are lost during fox control programs, the impact on populations is low.
Removing the predators that otherwise prey on these native species or compete for their food, is a greater benefit than the risk, so the balance of acceptable risk is in favour of using baits to control introduced predators.
Risks to non-target animals are further reduced by the burying or covering baits, which reduces access to baits by birds and small native mammals, while not impeding uptake by foxes.
The PAPP dose in FOXECUTE® baits is 400mg. This is ample to kill a fox weighing 5-7 kg, but may not be sufficient to kill a large dog. Moreover, because the effects are fast and the affected animal will feel lethargic, a larger dog that takes one fox bait is unlikely to have time to find additional fox bait(s) if baits are placed well apart. The dose used for the control of wild dogs in DOGABAIT is 1000mg/bait and this is a lethal dose for proven knockdown of any sized dog.
The lower dosing of FOXECUTE® baits for fox control creates a small margin of safety for some pets and working dogs. However, this is not absolute and small dogs would still be vulnerable to the fox dose, so normal protective measures are still required for pets and working dogs.
Restraining or muzzling working dogs while they are in baited areas is essential. If a dog has access to more than a single fox bait they will also be at high risk, so containers of PAPP baits must be stored securely.
For a description of how PAPP works as an active see: http://www.animalcontrol.com.au/PAPP01.htm
PAPP does not bio-accumulate and it is metabolised and excreted quickly. Any animal that receives a sub-lethal exposure is able to quickly clear the toxin from the system and will have no long-term effects. Within a few hours a partially dosed animal will return to normal.
PAPP, like 1080, also degrades in the environment, though the breakdown rate for PAPP in baits is slower than for 1080 in baits. This is also dependent upon soil temperature and moisture content.
Indicative studies have shown that buried FOXECUTE® baits under field conditions retain lethal doses up to several weeks after deployment. This is longer than the typical 1 – 2 week period for which 1080 baits remain lethal in moist soil.
The levels of PAPP residue in a carcass are very low. Sufficient tissue could not be eaten quickly enough to lead to secondary poisoning of any scavenging animal.
A fox killed by a PAPP type bait will typically show a grey or blueish colour on the tongue and gums due to the loss of oxygen to tissues. If a pet or working dog is suspected of PAPP poisoning this discolouration of the tongue is a critical warning sign and indicates the need for quick intervention.
Any compound, that converts methaemoglobin back to normal haemoglobin can reverse the effects of PAPP, even if an affected animal is close to death. Response to treatment is immediate.
A common antidote to methaemoglobinaemia is methylene blue, when injected intravenously. Sterile methylene blue solution is commercially available as a human medicine and vets can purchase this product. A ready-to-use product for dog owners is not yet available.
Advisory information about PAPP has been provided to all veterinarians and training is to be incorporated into new veterinary teaching programs.
Most large animal vets will already have supplies of methylene blue as it is used to treat nitrate/nitrite poisoning in cattle.
As PAPP acts quickly it is imperative to intervene as quickly as possible in an emergency.
It is necessary to get the affected non-target animal to a vet as soon as possible after ingesting a PAPP bait. During the early stages of toxicosis, dog owners can also induce vomiting via oral doses of salt water to an accidentally poisoned dog. Depending on how much bait has been absorbed, the time to death will typically be 45-90 minutes. This means that it may not be possible to administer the antidote fast enough in remote areas.
We strongly recommend fitting muzzles to or chain restraints on working dogs and pets if they are near a baited area.
Another feature incorporated into PAPP baits by ACTA is the inclusion of small plastic marker beads. These remain in the stomach or gut of an animal that is killed and can even be found in a long-decayed carcass.
The marker beads used in PAPP baits are yellow/orange whereas those to be used in 1080 bait manufactured by ACTA are red. If a dog is presented to a veterinarian and it can be made to vomit, the nature of the poison can be immediately determined by the colour of the beads.
Moreover, dogs that have become ill for other reasons, such as snake bite (a common cause of death in farm dogs), will have no beads present. This increases the ability of veterinarians to diagnose the correct course of treatment and will help overcome some false claims that pets or other wildlife have been killed by baits when there is another cause of death.
PAPP is synthesised from a precursor chemical called aniline, but its synthesis requires special conditions and releases corrosive by-products that can damage reaction equipment. Therefore PAPP is more expensive than 1080 to synthesise. Also, high doses of PAPP for dogs and foxes are required (400 or 1000mg PAPP per bait compared to 3 or 6 mg of 1080 respectively). Additionally the cost of gaining regulatory approval has been high. A royalty from sales will be returned to the IA-CRC and AWI to assist in further research into pest animal management.
FOXECUTE® Baits, in pails of 10 or 40 baits, are available from the local authorised control agency in each state::
VIC: Department of Primary Industries
NSW: Rural Land Protection Boards
SA: Natural Resources Management Boards
QLD: Department of Natural Resources, Mines & Energy and Local Government Land Protection Officers
ACT: Department of Environment and Planning
Western Australia: Rural Merchants Licensed to retail S7 products
FOXECUTE® is also made available to Government Conservation Agencies and National Parks in most states for protection of native animals in Crown Land areas.
Animal Control Technologies (Australia) Pty Ltd
46-50 Freight Drive
Somerton, Victoria, 3062
Telephone +61 3 9308 9688
Fax +61 3 9308 9622