Defra and Immunocontraception


        "When I raised this with DEFRA I got told this rubbish about no proof of immunocontraceptive injected animals entering the food chain. That was not long after I'd shot a tagged sow that went into the food chain via a local game dealer!" - Posted on an on-line shooting forum. July 10, 2009.

        Defra in conjunction with the Forestry Commission are conducting ground breaking research trialing chemical contraception as a method of reducing wild boar numbers in the Forest of Dean. This form of population control will reduce or negate the need for shooting, which is a less publicly acceptable form of population control. The research, involving the gonadotropin releasing hormone (GnRH) under the trade name GonaConTM has been underway for three years. The hormone has been shown to be effective in preventing sows in captive enclosures from becoming pregnant, and also in trapped, vaccinated and then released free-living wild boar in the Forest of Dean. However, for the method to be a cost-effective practical management option, Defra need to develop a way of delivering the vaccine to wild boar added to a bait that only wild boar will eat. Otherwise other woodland wildlife may inadvertantly consume the immunocontraceptive-laced bait. The effects of GonaCon, which has only recently been developed, in other species, or on woodland ecology in general, are not known.

Defra's wild boar feeder Wild boar feeder in the Forest of Dean (reproduced with permission).

Defra's unique wild boar feeder - designed to administer immunocontraceptive laced-bait to only wild boar, and no other woodland species.

        The idea is that the upper lid is so heavy (12-15kg) only a wild boar can lift it to get at the bait underneath it. It is shown here open as the boar need to get used to finding the bait. When they learn it's there, the lid is dropped, only to be opened by wild boar as they alone have the strength. Using this system, Defra hope to be able to administer immunocontaceptives to wild boar without the need for trapping or darting the animal, which is an expensive and time-consuming process. This is an ingenious device, and part of important research, but it also raises some interesting points, which I list below. I would be very interested to hear of other peoples thoughts on this device, so do please email us at British Wild Boar with your thoughts.

Interesting points raised by this device

        1. How does this system discriminate between different wild boar with regard to sex, size or age? When administering drugs to ainimals, vets and researchers administer carefully measured doses, but with this device certain wild boar are in danger of getting dosed-up to the eyeballs with the immunocontraceptive (regardless of their sex, size or age) with no data available to show if this is safe or harmfull to the animal.

        2. Wild boar are messy eaters and even if only wild boar, through intelligence or brute force, are the only species able to open a dedicated feeding device, they will spill part of what they eat onto the forest floor making it available to non-target species. When observing wild boar at bait stations, I was always amused to see kamikaze mice dash between stomping trotters to grab a morsel of grain before rapidly retreating. Mice that are then eaten by a host of other species and so on up the food chain. I also watched chaffinches, blackbirds, pheasants, and rabbits all dine out on the scraps from the wild boars’ table. The effect of the immunocontaceptive on small non-target species through direct consumption or environmental contamination is, as far as we can ascertain through literature searches, unknown, and more research would be required in this field.






A squirrel chomping on grain surrounding the feeding device - if this bait contained an oral immunocontraceptive [it doesn't - this is only a trial], any spillage would become available to all the woodlands' birds, animals, amphibians and so on up the food chain. (photo Martin Goulding)


        3. Having watched wild boar toss logs of wood the size of railway sleepers about as if they were match sticks (to get at grain strategically placed underneath), we wonder about the longevity or biosecurity of such a feeding device. We suspect that under field conditions the device is at risk of being knocked or tilted over, potentially spilling its contents to any woodland species that passes by, with unknown consequences to that species or the woodlands ecology - the device in the photograph is noticeably at a 'jaunty angle'.

Communications to the website received to-date

        1. A local natural historian has reported that since the baiting experiment started a lot more deer have been noticed in the area. They are feeding from the site as well, and also starting to use the boar's wallows and scratching trees. The deer should not be able to raise the lid to access any drug-laden bait, however, they will be able to feed on spilt grain or left-overs. The local historian points out that wild boar are messy eaters and leave grain all over the place for other animals to clean it up. They may eat it all, but if disturbed will run away and leave it for others to clean up. However, the lid falling back down would prevent access to grain by other animals, although there is likely to be some grain spilt as the boar hurriedly removed their snout.

        2. A retired wild boar/domestic pig PhD scientist emails: "On welfare grounds, the ablation of ovarian function including hormone production may well affect the behaviour of the sows and cause instability in social behaviour of the sounder and in the more general boar population. Now that we have wild boar back in the wild with us, let's accept them and give them a life here in the UK, as natural as possible. The traditional approach of population control by controlled/approved hunting measures is still my favoured method - the species survives in as natural a way as possible and we can enjoy the meat! Part of our past heritage can then be restored, compared with our continental neighbours we desperately need to do this."


Defra have added great lumps of meat to the feeder (see photo below). We have no idea why - answers on a postcard please (reproduced with permission). Click here for a press report from The Forester newspaper

Defra's wild boar feeder with meat

The answer has come!: from a question asked in the House of Commons!  

Mr. Harper: "To ask the Secretary of State for Environment, Food and Rural Affairs
   (1) in what circumstances wild boar may be fed meat; and if he will make a statement;
   (2) what precautions the Food and Environment Research Agency has put in place to prevent the spread of disease among wild boar populations which are fed meat."

Jane Kennedy: "Wild boar cannot normally be fed meat unless it is fed for research purposes and is done in accordance with an authorisation. DEFRA has issued a general authorisation for use of animal by-products for research purposes. The Secretary of State can also issue individual authorisations and can suspend or revoke authorisations.

Although the feeding of animal by-products to animals is a potential route of transmission of various diseases and is something that is not sanctioned in farming or domestic feeding practice, this isolated, short-term trial involving wild boar took place at a time when foot and mouth disease (FMD) and other exotic diseases were 5 May 2009 : Column 9W not present in GB. As such, DEFRA is confident that this particular activity did not increase the risk of introducing FMD or other exotic disease. No additional measures, beyond regular surveillance of the feral wild boar by research scientists, are considered necessary.

The Food and Environment Research Agency does not currently feed any meat to any wild boar populations. In January 2009, as part of the agency’s research on managing wild boar populations, meat was used at a single research site."

So, that's all OK then, is it?!




Results published to-date concerning the Boar-Operated-System

Early results from Defra's immunocontraception project in the Forest of Dean are posted below, along with other relevant research on wild boar feeding devices from outside the UK - We will add more as they become available.

Evaluation of Feral Swine-Specific Feeder Systems David Long, Tyler Campbell, and Giovanna Massei. Rangelands In-Press.

        Abstract: Feral swine have been introduced across many rangeland ecosystems of the United States. Our objective was to evaluate candidate non-target exclusion feeder systems for feral swine as a means to deliver baits containing pharmaceuticals. The percent decrease in bait removal following the activation of the boar operated systems (BOS) was 48% for feral swine and 100% for all other species. The percent decrease in bait removal following the activation of the non-target exclusion device was 19, 28, 100, and 100% for raccoons, feral swine, white-tailed deer, and collared peccaries, respectively.

The complete article can be viewed here: Evaluation of Feral Swine-Specific Feeder Systems

The Boar-Operated-System: a Novel Method to Deliver Baits to Wild Pigs Giovanna Masseia, Julia Coats, Roger Quy, Kate Storer, and Dave P. Cowan

        Abstract: Bait-delivered pharmaceuticals, increasingly used to manage populations of wild boar (Sus scrofa) and feral pigs, may be ingested by nontarget species. Species-specificity could be achieved through a delivery system. We designed the BOS™ (Boar-Operated-System) as a device to deliver baits to wild pigs. The BOS™ consists of a metal pole onto which a round perforated base is attached. A metal cone with a wide rim slides up and down the pole and fully encloses the base onto which the baits are placed. We conducted a pilot, captive trial and found that captive wild boar fed from the BOS™ either directly, by lifting the cone, or indirectly, by feeding once another animal had lifted the cone. Thus, we tested whether free-living wild boar fed from the BOS™ and whether the BOS™ could prevent bait uptake by nontarget species. We observed that free-living wild boar fed regularly from the BOS™ and that the device successfully prevented bait uptake by nontarget species. The BOS™ should be trialed more extensively to confirm its effectiveness and species-specificity to distribute pharmaceuticals to wild suids. If successful, the BOS™ could be used to deliver vaccines in disease control programs as well as contraceptives to manage overabundant populations of wild suids.

The complete article can be purchased here: The Boar-Operated-System: a Novel Method to Deliver Baits to Wild Pigs

The BOS (Boar-Operated-System): a novel method to deliver baits to wild boar 2008 National Conference on Feral Hogs, April 13–15, 2008, Missouri, USA

        Bait-delivered contraceptives and vaccines against diseases are increasingly used in wildlife management. These drugs may be ingested by target and non-target species. Species-specificity can be achieved by delivery. We designed the BOS (Boar-Operated-System) as a device to deliver baits to wild boar. The BOS consists of a metal pole onto which a round mesh base is attached. A metal cone with a wide brim slides up and down the pole and fully encloses the base onto which the baits are placed. Tests carried out with captive and free-living wild boar showed that the BOS is an effective, relatively inexpensive and species-specific device to deliver contraceptives and other pharmaceuticals to wild boar. In parallel, we tested systemic bait markers (Iophenoxic Acid and Rhodamine B) to determine rates of bait uptake by wild boar. The results indicated that Rhodamine B can be used to identify the proportion of animals that consumed baits. Iophenoxic Acid can also be used as a long-term, semi-qualitattive marker to estimate the number of baits ingested by wild boar.

Effectiveness and Potential Side Effects of the Immunocontraceptive Vaccine ConaConTM on The Wild Boar 2008 National Conference on Feral Hogs, April 13–15, 2008, Missouri, USA

        This study tested the effectiveness and potential side effects of the single-dose immunocontraceptive Gonadotropin Releasing Hormone (GnRH) vaccine GonaConTM on captive wild boar. Twenty-four females were used: 12 control, 6 treated with the vaccine in 2004 and 6 treated in 2006. The effectiveness of GonaConTM to induce infertility was monitored by measuring serum antibodies to the GnRH vaccine and by using the concentration of faecal progesterone as an indicator of oestrus in females. Behavioural data on time budget and dominance ranks were collected before and after vaccination. Body weight and physiological data were derived from health profiles based on serum samples collected at vaccination and after vaccination. All control females gave birth. All females vaccinated in 2004 and 5 of the 6 females vaccinated in 2006 were still infertile in 2008. No differences in time budget, social ranks, biochemical and haematological parameters and body weight were observed between treated and controls. The results of this study suggest that GonaConTM is as an effective, humane and safe contraceptive for wild boar.


        Details of the immunocontraceptive project, being carried out by Defra on the free-living wild boar in Ross-on-Wye, are detailed here Towards Practical Application of Emerging Fertility Control Technologies for Wildlife Management - WM0408 Cost = £993,336 (first 3 years) + £814,994 (3 year extension) = £1,808,330

Questions put to Defra

Several questions concerning Defra's study of the administration of immunocontraceptive drugs to the wild boar in the Forest of Dean Towards Practical Application of Emerging Fertility Control Technologies for Wildlife Management - WM0408 have been put to Defra by interested individuals or journalists. The responses are given below:


Question

1. What precautions have been taken to ensure that only boar eat the the feed and thus contraceptive and to prevent non-target animals taking it, this would include deer, squirrels, rabbits, mice, dogs, sheep and ponies?

Defra response

Free-living animals have so far only been given contraceptives through injection and therefore there has been no need to take measures to prevent non-target animals taking treated feed.

Question

2. Has any research been done on the possible effect of other animals eating the contraceptive as from your report it would seem that it is not species specific?

Defra response

The contraceptive approaches being considered are not species-specific. Thus if oral delivery via bait is to be considered then methods of making baits available to only the target species will need to be developed. This is a challenging issue that is being addressed by the current project. No baits will be made available to free-living populations unless suitable species-specific delivery methods are developed.

Question

3. Some boar treated with contraceptive have entered the food chain, has any research been carried out to discover the possible effect on humans of eating such an animal?

Defra response

It is not known that any vaccinated boar have entered the food chain. However, should this occur there is no known viable mechanism by which effects on humans could arise as a result of eating such an animal. The specific product used has been considered by the United States Food and Drug Administration not to raise a human food safety concern and other very similar vaccines are used elsewhere in livestock production for treating animals that subsequently enter the human food chain.

Defra is not aware of any evidence that tagged wild boar have definitely entered the food chain.

Question

4. Nearly £1m of tax payers money has been spent on this project, why wasn't the research targeted at a much more prolific and potentially harmful mammal such as exotic deer species including muntjac or sika which currently present a much greater threat to the environment on a much wider basis than the native wild boar that according to your reports number less than 1000 in principally just three locations. Exotic deer species by comparison number in the high hundreds of thousands and are present in a high proportion of 10km squares in the UK and are increasing rapidly in range and numbers posing serious issues of damage to trees and crops and, in the case of sika, interbreeding with the native reds to the extent that the genetic integrity of virtually every red deer in Scotland is questionable?

Defra response

The immunocontraception work is proof of the concept of the technique. The species being used for development of the technique is not indicative of those which it may be used on in future if the project is successful.

Question

5. Why is the Forestry Commission carrying out a programme of substantial culling of boar, principally in the southern Forest of Dean, and presumably without the sanction of DEFRA or English Nature before DEFRA have issued their policy proposals following the consultation?"

Defra response

There is no substantial culling of wild boar taking place at the present time. Current Forest Enterprise policy is that boar are only culled on an individual basis where they have directly caused problems relating to health and safety.

Future policy as to the management of wild boar populations is under review following the recent public consultation.

As regards the alleged shooting of ‘over 40’ wild boar in the Forest of Dean, we can advise that to date Forestry Commission rangers there have killed just 2 wild boar, and both those animals had repeatedly attacked dogs being walked by people. This is in accordance with Defra’s current policy.

Question- from Mark Harper MP to the House of Lords

6. Mr. Harper: To ask the Secretary of State for Environment, Food and Rural Affairs (1) under what circumstances wild boar may be fed meat; and if he will make a statement; (2) what precautions the Food and Environment Research Agency has put in place to prevent the spread of disease among wild boar populations which are fed meat.

Response

Jane Kennedy: Wild boar cannot normally be fed meat unless it is fed for research purposes and is done in accordance with an authorisation. DEFRA has issued a general authorisation for use of animal by-products for research purposes. The Secretary of State can also issue individual authorisations and can suspend or revoke authorisations.

Although the feeding of animal by-products to animals is a potential route of transmission of various diseases and is something that is not sanctioned in farming or domestic feeding practice, this isolated, short-term trial involving wild boar took place at a time when foot and mouth disease (FMD) and other exotic diseases were not present in GB. As such, DEFRA is confident that this particular activity did not increase the risk of introducing FMD or other exotic disease. No additional measures, beyond regular surveillance of the feral wild boar by research scientists are considered necessary.

The Food and Environment Research Agency does not currently feed any meat to any wild boar populations. In January 2009, as part of the agency’s research on managing wild boar populations, meat was used at a single research site.

Question- from The Forester (a Forest of Dean local newspaper)

7.a) did Defra still consider the experiment to have been carried out in a controlled environment in light of the new pictures and b)what was the scientific rationale for using meat.

Response

A wild boar fertility control project is currently underway studying possible ways of using effective and humane methods of contraception. If a safe, effective and humane oral contraceptive is identified for wild boar, this will have to be delivered in baits. As part of the study, we are evaluating methods to deliver baits to wild boar.

“A pilot field trial was carried out in January 2009 to determine whether this would work with feral wild boar. A variety of bait including a mixture of peanuts, maize and local deer meat was used as bait to attract the wild boar.

“Under Animal by-products regulations, wild boar can only be fed meat for approved diagnostic, research or educational purposes. This was an approved trial.”

Any others?

If you have any questions to ask Defra concerning their researches into the management of the wild boar, Defra give out this contact email address: e.environment@defra.gsi.gov.uk.

If anyone has any other Defra responses that would be of interest, we would be delighted to hear. please email Thank-you.

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