1
|
Robertson A, Palphramand KL, McDonald RA, Middleton S, Chambers MA, Delahay RJ, Carter SP. Uptake of baits by wild badgers: Influences of deployment method, badger age and activity patterns on potential delivery of an oral vaccine. Prev Vet Med 2022; 206:105702. [DOI: 10.1016/j.prevetmed.2022.105702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 06/16/2022] [Accepted: 06/26/2022] [Indexed: 10/17/2022]
|
2
|
Payne A, Ruette S, Jacquier M, Richomme C, Lesellier S, Middleton S, Duhayer J, Rossi S. Estimation of Bait Uptake by Badgers, Using Non-invasive Methods, in the Perspective of Oral Vaccination Against Bovine Tuberculosis in a French Infected Area. Front Vet Sci 2022; 9:787932. [PMID: 35359678 PMCID: PMC8961513 DOI: 10.3389/fvets.2022.787932] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/07/2022] [Indexed: 11/14/2022] Open
Abstract
Although France is officially declared free of bovine tuberculosis (TB), Mycobacterium bovis infection is still observed in several regions in cattle and wildlife, including badgers (Meles meles). In this context, vaccinating badgers should be considered as a promising strategy for the reduction in M. bovis transmission between badgers and other species, and cattle in particular. An oral vaccine consisting of live Bacille Calmette–Guérin (BCG) contained in bait is currently under assessment for badgers, for which testing bait deployment in the field and assessing bait uptake by badgers are required. This study aimed to evaluate the bait uptake by badgers and determine the main factors influencing uptake in a TB-infected area in Burgundy, north-eastern France. The baits were delivered at 15 different setts located in the vicinity of 13 pastures within a TB-infected area, which has been subject to intense badger culling over the last decade. Pre-baits followed by baits containing a biomarker (Rhodamine B; no BCG vaccine) were delivered down sett entrances in the spring (8 days of pre-baiting and 4 days of baiting) and summer (2 days of pre-baiting and 2 days of baiting) of 2018. The consumption of the marked baits was assessed by detecting fluorescence, produced by Rhodamine B, in hair collected in hair traps positioned at the setts and on the margins of the targeted pastures. Collected hairs were also genotyped to differentiate individuals using 24 microsatellites markers and one sex marker. Bait uptake was estimated as the proportion of badgers consuming baits marked by the biomarker over all the sampled animals (individual level), per badger social group, and per targeted pasture. We found a bait uptake of 52.4% (43 marked individuals of 82 genetically identified) at the individual level and a mean of 48.9 and 50.6% at the social group and pasture levels, respectively. The bait uptake was positively associated with the presence of cubs (social group level) and negatively influenced by the intensity of previous trapping (social group and pasture levels). This study is the first conducted in France on bait deployment in a badger population of intermediate density after several years of intensive culling. The results are expected to provide valuable information toward a realistic deployment of oral vaccine baits to control TB in badger populations.
Collapse
Affiliation(s)
- Ariane Payne
- Wildlife Disease Unit, French Office for Biodiversity, Orléans, France
- Groupement de Défense Sanitaire de Côte d'Or, Breteniere, France
- *Correspondence: Ariane Payne
| | - Sandrine Ruette
- French Office for Biodiversity, Predators and Alien Species Unit, Birieux, France
| | - Mickaël Jacquier
- French Office for Biodiversity, Predators and Alien Species Unit, Birieux, France
- Claude Bernard Lyon 1 University, CNRS UMR5558, LBBE, Villeurbanne, France
| | - Céline Richomme
- ANSES, Nancy Laboratory for Rabies and Wildlife, Malzéville, France
| | - Sandrine Lesellier
- ANSES, Nancy Laboratory for Rabies and Wildlife, Malzéville, France
- Animal and Plant Health Agency, Woodham Lane, United Kingdom
| | - Sonya Middleton
- Animal and Plant Health Agency, Woodham Lane, United Kingdom
| | - Jeanne Duhayer
- Claude Bernard Lyon 1 University, CNRS UMR5558, LBBE, Villeurbanne, France
| | - Sophie Rossi
- Wildlife Disease Unit, French Office for Biodiversity, Orléans, France
| |
Collapse
|
3
|
Chen R, Little R, Mihaylova L, Delahay R, Cox R. Wildlife surveillance using deep learning methods. Ecol Evol 2019; 9:9453-9466. [PMID: 31534668 PMCID: PMC6745675 DOI: 10.1002/ece3.5410] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/20/2019] [Accepted: 05/23/2019] [Indexed: 11/26/2022] Open
Abstract
Wildlife conservation and the management of human-wildlife conflicts require cost-effective methods of monitoring wild animal behavior. Still and video camera surveillance can generate enormous quantities of data, which is laborious and expensive to screen for the species of interest. In the present study, we describe a state-of-the-art, deep learning approach for automatically identifying and isolating species-specific activity from still images and video data.We used a dataset consisting of 8,368 images of wild and domestic animals in farm buildings, and we developed an approach firstly to distinguish badgers from other species (binary classification) and secondly to distinguish each of six animal species (multiclassification). We focused on binary classification of badgers first because such a tool would be relevant to efforts to manage Mycobacterium bovis (the cause of bovine tuberculosis) transmission between badgers and cattle.We used two deep learning frameworks for automatic image recognition. They achieved high accuracies, in the order of 98.05% for binary classification and 90.32% for multiclassification. Based on the deep learning framework, a detection process was also developed for identifying animals of interest in video footage, which to our knowledge is the first application for this purpose.The algorithms developed here have wide applications in wildlife monitoring where large quantities of visual data require screening for certain species.
Collapse
Affiliation(s)
- Ruilong Chen
- Department of Automatic Control and Systems EngineeringUniversity of SheffieldSheffieldUK
| | - Ruth Little
- Department of GeographyUniversity of SheffieldSheffieldUK
| | - Lyudmila Mihaylova
- Department of Automatic Control and Systems EngineeringUniversity of SheffieldSheffieldUK
| | - Richard Delahay
- National Wildlife Management CentreAnimal and Plant Health AgencyGloucestershireUK
| | - Ruth Cox
- National Wildlife Management CentreAnimal and Plant Health AgencyGloucestershireUK
| |
Collapse
|
4
|
Carter SP, Robertson A, Palphramand KL, Chambers MA, McDonald RA, Delahay RJ. Bait uptake by wild badgers and its implications for oral vaccination against tuberculosis. PLoS One 2018; 13:e0206136. [PMID: 30412584 PMCID: PMC6226152 DOI: 10.1371/journal.pone.0206136] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 10/08/2018] [Indexed: 12/30/2022] Open
Abstract
The deployment of baits containing vaccines or toxins has been used successfully in the management of wildlife populations, including for disease control. Optimisation of deployment strategies seeks to maximise uptake by the targeted population whilst ensuring cost-effectiveness. Tuberculosis (TB) caused by infection with Mycobacterium bovis affects a broad range of mammalian hosts across the globe, including cattle, wildlife and humans. The control of TB in cattle in the UK and Republic of Ireland is hampered by persistent infection in European badgers (Meles meles). The present study aimed to determine the best strategy for maximising uptake of an oral vaccine by wild badgers, using a surrogate novel bait deployed at 40 badger social groups. Baits contained a blood-borne biomarker (Iophenoxic Acid, IPA) in order to measure consumption in badgers subsequently cage trapped at targeted setts. Evidence for the consumption of bait was found in 83% (199/240) of captured badgers. The probability that badgers had consumed at least one bait (IPA >10 μg ml-1) was significantly higher following deployment in spring than in summer. Lower uptake amongst social groups where more badgers were captured, suggested competition for baits. The probability of bait consumption was significantly higher at groups where main and outlier setts were provided with baits than at those where outliers were present but not baited. Badgers captured 10-14 days post bait feeding had significantly higher levels of bait uptake compared to those caught 24-28 days later. Uptake rates did not vary significantly in relation to badger age and whether bait was placed above ground or down setts. This study suggests that high levels of bait uptake can be achieved in wild badger populations and identifies factors influencing the potential success of different deployment strategies. The implications for the development of an oral badger vaccine are discussed.
Collapse
Affiliation(s)
- Stephen P. Carter
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, United Kingdom
- Vincent Wildlife Trust, Eastnor, Ledbury, Herefordshire, United Kingdom
| | - Andrew Robertson
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, United Kingdom
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, United Kingdom
| | - Kate L. Palphramand
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, United Kingdom
| | - Mark A. Chambers
- Department of Bacteriology, Animal and Plant Health Agency, Weybridge, Woodham Lane, New Haw, Surrey, United Kingdom
| | | | - Richard J. Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, United Kingdom
| |
Collapse
|
5
|
Perrett S, Lesellier S, Rogers F, Williams GA, Gowtage S, Palmer S, Dalley D, Davé D, Weyer U, Wood E, Salguero FJ, Nunez A, Reed N, Chambers MA. Assessment of the safety of Bacillus Calmette-Guérin vaccine administered orally to badgers (Meles meles). Vaccine 2018. [PMID: 29525277 DOI: 10.1016/j.vaccine.2018.02.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
European badgers (Meles meles) are a wildlife reservoir for Mycobacterium bovis (M. bovis) in parts of England, Wales and Ireland, constituting a potential source of tuberculosis (TB) infection for cattle. Vaccination of badgers against TB is one of the tools available for helping reduce the prevalence of bovine TB in badgers, made possible by the licensing in 2010 of Bacillus Calmette-Guérin (BCG) vaccine for intramuscular administration to badgers (BadgerBCG). However, practical limitations associated with administering an injected vaccine to wild animals make an oral, bait-delivered form of the vaccine highly desirable. Evaluation of the safety of oral BCG to badgers and the environment is a mandatory step on the road to licensing an oral vaccine. This study had the following objectives: (a) to determine whether adverse effects followed the oral administration of BCG vaccine to badgers; (b) to measure the quantity and frequency of BCG excreted in the faeces of vaccinated badgers; and (c) to assess whether there was evidence of the vaccine spreading to unvaccinated, 'sentinel' badgers sharing the same environment as vaccinated animals. We report here that the oral administration per badger of ≥6.4 × 109 cfu BCG, followed 14 days later by a single oral dose of ≥6.4 × 107 cfu BCG caused no adverse physical effects and did not affect the social behaviour and feeding habits of the vaccinated animals. BCG was cultured from the faeces of two of nine vaccinated animals (372 cfu/g and 996 cfu/g, respectively) approximately 48 h after the higher dose of BCG was administered and by one of the nine vaccinated animal (80 cfu/g) approximately 24 h after receiving the lower dose of BCG. We found no evidence for the transmission of BCG to unvaccinated, sentinel, badgers housed with the vaccinated animals despite the occasional excretion of BCG in faeces.
Collapse
Affiliation(s)
- Simon Perrett
- Scientific Services Unit, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Sandrine Lesellier
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Fiona Rogers
- National Wildlife Management Centre, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Gareth A Williams
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Sonya Gowtage
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Si Palmer
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Deanna Dalley
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Dipesh Davé
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Ute Weyer
- Animal Services Unit, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Emma Wood
- Surveillance and Laboratory Services, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Francisco J Salguero
- Department of Pathology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Alex Nunez
- Department of Pathology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Nick Reed
- Scientific Services Unit, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Mark A Chambers
- Department of Bacteriology, Animal and Plant Health Agency, New Haw, Addlestone, Surrey KT15 3NB, UK.
| |
Collapse
|
6
|
Field evaluation of candidate baits for oral delivery of BCG vaccine to European badgers, Meles meles. Vaccine 2017; 35:4402-4407. [PMID: 28689652 DOI: 10.1016/j.vaccine.2017.06.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/06/2017] [Accepted: 06/15/2017] [Indexed: 11/22/2022]
Abstract
The control of tuberculosis (TB) in cattle in the UK and Ireland is compromised by transmission of Mycobacterium bovis to cattle from the European badger (Meles meles), which acts as a wildlife reservoir. Vaccination of badgers could potentially contribute to TB control but the only licensed vaccine is injectable BadgerBCG which requires the live-capture of badgers. Current research is aimed at developing an oral TB vaccine (where vaccine is contained within bait) that is intended to be more cost-effective to deploy over large areas. In order to identify a lead product, candidate baits identified from captive badger studies were evaluated in three successive bait screening studies with wild badgers. A fourth field study, using the lead candidate bait and biomarkers, investigated the effectiveness of different carriers for their potential to deliver liquid payloads (vaccine surrogate). In each field study, bait disappearance was monitored daily for ten days and remote video surveillance was used to determine preference (i.e. the order in which baits were taken). In the carrier study, biomarkers were used to determine what proportion of subsequently trapped badgers had ingested the bait and the vaccine-carrier biomarker payload. Across all four studies, 79% (3397/4330) of baits were taken by badgers although the number varied significantly by badger social group and bait type. In all studies, bait disappearance increased over time, with 75-100% of baits being taken by day ten. In the carrier study, 75% (9/12) of trapped badgers tested positive for at least one of the biomarkers and the type of carrier did not influence bait attractiveness. Together with data from complementary laboratory and captive animal studies, this study identified a highly attractive and palatable bait (peanut-based paste bait; PT) and vaccine-carrier (hydrogenated peanut oil; HPO) combination with the potential to deliver a liquid vaccine to wild badgers.
Collapse
|
7
|
Robertson A, Delahay RJ, McDonald RA, Aylett P, Henderson R, Gowtage S, Chambers MA, Carter SP. Behaviour of European badgers and non-target species towards candidate baits for oral delivery of a tuberculosis vaccine. Prev Vet Med 2016; 135:95-101. [PMID: 27931935 DOI: 10.1016/j.prevetmed.2016.11.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 11/12/2016] [Accepted: 11/12/2016] [Indexed: 11/25/2022]
Abstract
In the UK and the Republic of Ireland, the European badger (Meles meles) is a maintenance host for Mycobacterium bovis, and may transmit the infection to cattle causing bovine tuberculosis (TB). Vaccination of badgers using an injectable Bacillus Calmette-Guerin (BCG) vaccine is undertaken in some areas of the UK with the intention of interrupting this transmission, and vaccination research is underway in Ireland. An oral badger TB vaccine is also under development. We investigated the behaviour of badgers and non-target wildlife species towards three candidate baits being considered for delivering BCG to badgers orally. Bait preference was investigated by recording removal rates of baits and through the use of video surveillance at 16 badger setts. We found high variation in rates of bait removal by badgers among setts but no significant differences in removal rates among bait types or in preference behaviour from video footage. Variation in bait removal among setts correlated with the number of nights on which badgers were seen at the sett, with most baits being removed where badgers were seen on >50% of nights during the ten-day study period. Relatively few baits were removed at setts with low levels of recorded badger activity. Monitoring badger activity prior to bait deployment may therefore be useful in increasing bait uptake and vaccine coverage. Bait removal by badgers increased over the ten-day study period, suggesting initial neophobic behaviour at some setts and that a period of 'pre-feeding' may be required prior to vaccine deployment. Our results indicate that all three candidate baits are attractive to badgers. Removal of baits by non-target wildlife species was generally low, but varied among bait types, with smaller baits in packaging less likely to be removed. Enclosing baits in packaging is likely to deter non-target species, although in some cases non-target species did remove up to 13% of packaged baits.
Collapse
Affiliation(s)
- Andrew Robertson
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9EZ, UK; National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK.
| | - Richard J Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK
| | - Robbie A McDonald
- Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, TR10 9EZ, UK
| | - Paul Aylett
- Connovation, 36 B Sir William Ave, East Tamaki, Manukau, PO Box 58613, New Zealand
| | - Ray Henderson
- Pest-Tech Limited, 233 Branch Drain Road, Rd 2, Leeston, 7682, New Zealand
| | - Sonya Gowtage
- Department of Bacteriology, Animal and Plant Health Agency, Weybridge, Woodham Lane, New Haw, Surrey, KT15 3NB, UK
| | - Mark A Chambers
- Department of Bacteriology, Animal and Plant Health Agency, Weybridge, Woodham Lane, New Haw, Surrey, KT15 3NB, UK; School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7X H, UK
| | - Stephen P Carter
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire, GL10 3UJ, UK
| |
Collapse
|
8
|
Abstract
In approaching the development of a veterinary vaccine, researchers must choose from a bewildering array of options that can be combined to enhance benefit. The choice and combination of options is not just driven by efficacy, but also consideration of the cost, practicality, and challenges faced in licensing the product. In this review we set out the different choices faced by veterinary vaccine developers, highlight some issues, and propose some pressing needs to be addressed.
Collapse
Affiliation(s)
- Mark A Chambers
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7AL, UK.
- Department of Bacteriology, Animal and Plant Health Agency, Addlestone, Surrey, KT15 3NB, UK.
| | - Simon P Graham
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7AL, UK
- The Pirbright Institute, Ash Road, Pirbright, Woking, GU24 0NF, UK
| | - Roberto M La Ragione
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7AL, UK
| |
Collapse
|