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Wangmo K, Gurung RB, Choden T, Letho S, Pokhrel N, Lungten L, Zangmo T, Peldon S, Chedup K, Kumar SJ, Dorji T, Tshering S, Dorji K, Tenzin T. Seroprevalence and risk factors associated with bovine tuberculosis in cattle in Eastern Bhutan. PLoS Negl Trop Dis 2024; 18:e0012223. [PMID: 38805568 PMCID: PMC11161125 DOI: 10.1371/journal.pntd.0012223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 06/07/2024] [Accepted: 05/17/2024] [Indexed: 05/30/2024] Open
Abstract
Bovine tuberculosis (bTB) is a chronic zoonotic disease affecting cattle of all age groups including wild animals. It poses a significant threat to public health and high economic losses to dairy farmers. While the disease has been eradicated from most of the developed countries through extensive surveillance, testing and culling strategy, it is endemic in Africa, Asia, and the Middle East countries. Currently, there is limited research regarding the prevalence of bTB in cattle in Bhutan. This study aimed to determine the seroprevalence of bTB in cattle in six districts of eastern Bhutan. A two-stage probability proportional to size (PPS) sampling strategy was used to determine the number of animals from which serum samples needed to be collected in each district and sub-district. All farms and cattle for sampling were randomly selected from the data in the annual livestock census of 2020. The samples were tested using bTB ELISA test kit. The seroprevalence and their 95% confidence intervals were calculated. Logistic regression models were constructed to assess the influence of various individual animal and environmental risk factors (breed, age, sex, source of animal, body condition scores of animals, respiratory system status) associated with sero-positivity in animals. The study revealed an apparent seroprevalence of 2.57% (25/971 cattle; 95% CI:1.58-3.57), with an estimated true seroprevalence of 0.91% (95% CI: 0.0-2.81). However, none of the variables were found to be significantly associated with bTB seroprevalence in cattle. We recommend, further sampling and employment of confirmatory testing to fully ascertain the extent of bTB in the cattle herds in eastern Bhutan for prevention and control.
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Affiliation(s)
- Karma Wangmo
- Regional Livestock Development Centre, Department of Livestock, Khangma, Trashigang, Bhutan
| | - Ratna B Gurung
- National Centre for Animal Health, Department of Livestock, Thimphu, Bhutan
| | - Tshering Choden
- District Veterinary Hospital, Department of Livestock, Lhuentse, Bhutan
| | - Sangay Letho
- Regional Livestock Development Centre, Department of Livestock, Khangma, Trashigang, Bhutan
| | - Narayan Pokhrel
- District Veterinary Hospital, Department of Livestock, Mongar, Bhutan
| | - Lungten Lungten
- Regional Livestock Development Centre, Department of Livestock, Khangma, Trashigang, Bhutan
| | - Tashi Zangmo
- Regional Livestock Development Centre, Department of Livestock, Khangma, Trashigang, Bhutan
| | - Sonam Peldon
- National Centre for Animal Health, Department of Livestock, Thimphu, Bhutan
| | - Kinzang Chedup
- District Veterinary Hospital, Department of Livestock, Samdrup Jongkhar, Bhutan
| | | | - Thinley Dorji
- Kanglung Hospital, Ministry of Health, Trashigang, Bhutan
| | - Sangay Tshering
- Trashiyangtse hospital, Ministry of Health, Trashiyangtse, Bhutan
| | - Kinzang Dorji
- Eastern Regional Referral Hospital, Ministry of Health, Mongar, Bhutan
| | - Tenzin Tenzin
- National Centre for Animal Health, Department of Livestock, Thimphu, Bhutan
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Nyokabi NS, Phelan L, Gemechu G, Berg S, Lindahl JF, Mihret A, Wood JLN, Moore HL. From farm to table: exploring food handling and hygiene practices of meat and milk value chain actors in Ethiopia. BMC Public Health 2023; 23:899. [PMID: 37193991 DOI: 10.1186/s12889-023-15824-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 05/05/2023] [Indexed: 05/18/2023] Open
Abstract
Livestock value chains constitute a source of livelihood for meat and milk value chain actors in Ethiopia, from dairy farmers to other associated value chain actors such as milk traders, abattoir workers, public health officials, veterinarians, butcheries selling meats, milk cooperatives, artisanal milk processors, and transporters. The development of these livestock value chains, however, is constrained by poor food safety and quality, while consumers are also exposed to public health risks due to milk and meat value chain actors' food handling and hygiene practices.This study used Photovoice and participant observation to explore meat and milk value chain actors' food handling and hygiene practices in suburban areas of Addis Ababa and neighbouring Oromia in Ethiopia. The results of this study reveal that milk and meat value chain actors' food handling practices are not aligned with the recommended Ethiopian food safety and quality standards. Low compliance with food safety and quality standards reflected a combination of factors such as lack of incentives, poor road infrastructure and low enforcement of food safety standards.Participatory and visual research methods enable a researcher to collect context-aware data that can lead to the development of policies and intervention strategies that reflect local needs and priorities. The results of this study affirm the need to identify socially acceptable and economically viable policies and intervention strategies that are acceptable to all chain actors; and suggest there is an imperative to train milk and meat value chain actors on good hygiene handling practices, improve road infrastructure, and facilitate access equipment such as fridges and freezers that can contribute to maintaining food safety and quality.
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Affiliation(s)
- Ndungu S Nyokabi
- Institute for Global Prosperity, University College London, London, UK.
| | | | - Gizachew Gemechu
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Stefan Berg
- Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia
| | - Johanna F Lindahl
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya
- Department of Medical Biochemistry and Microbiology, Uppsala University, P.O. Box 582, 75123, Uppsala, Sweden
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, P.O. Box 7054, 75007, Uppsala, Sweden
| | - Adane Mihret
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | | | - Henrietta L Moore
- Institute for Global Prosperity, University College London, London, UK
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3
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Zhu X, Wang J, Zhao Y, Zhang Z, Yan L, Xue Y, Chen Y, Robertson ID, Guo A, Aleri J. Prevalence, distribution, and risk factors of bovine tuberculosis in dairy cattle in central China. Prev Vet Med 2023; 213:105887. [PMID: 36893605 DOI: 10.1016/j.prevetmed.2023.105887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 02/28/2023] [Accepted: 02/28/2023] [Indexed: 03/05/2023]
Abstract
Bovine tuberculosis (bTB) is one of the priority epidemic diseases in dairy cattle in China. Continuous surveillance and evaluation of the control programs will help on improving the efficiency of bTB control policy. We designed this study to investigate both animal and herd level prevalence of bTB, as well as to determine the associated factors in dairy farms in Henan and Hubei provinces. A cross-sectional study was conducted from May 2019 to September 2020 in central China (Henan and Hubei provinces). We sampled 40 herds in Henan and six herds in Hubei via stratified systematic sampling and administrated a questionnaire consisting of 35 factors. A total of 4900 whole blood samples were collected from 46 farms, including 545 calves < six months old and 4355 cows ≥ six months old. This study demonstrated a high animal-(18.65%, 95% CI: 17.6-19.8) and herd-level (93.48%, 95%CI: 82.1-98.6) prevalence of bTB in dairy farms in central China. The Least Absolute Shrinkage and Selection Operator (LASSO) and negative binomial regression models showed that herd positivity was associated with the practice of introducing new animals (RR = 1.7, 95%CI: 1.0-3.0, p = 0.042), and changing the disinfectant water in the wheel bath at the farm entrance every three days or less (RR = 0.4, 95%CI: 0.2-0.8, p = 0.005) which reduced the odds of herd positivity. In addition, the result illustrated that testing cows with a higher age group (≥ 60 months old) (OR=1.57, 95%CI: 1.14-2.17, p = 0.006) and within the early stage of lactation (DIM=60-120 days, OR=1.85, 95%CI: 1.19-2.88, p = 0.006) and the later stage of lactation (DIM≥301 days, OR=2.14, 95%CI: 1.30-3.52, p = 0.003) could maximize the odds of detecting seropositive animals. Our results have plenty of benefit to improve bTB surveillance strategies in China and elsewhere in the world. The LASSO and the negative binomial regression models were recommended when dealing with high herd-level prevalence and high dimensional data in questionnaire-based risk studies.
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Affiliation(s)
- Xiaojie Zhu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, Western Australia 6150, Australia
| | - Jie Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, Western Australia 6150, Australia
| | - Yuxi Zhao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Zhen Zhang
- Henan Dairy Herd Improvement Center, Zhengzhou, Henan 450045, China
| | - Lei Yan
- Henan Dairy Herd Improvement Center, Zhengzhou, Henan 450045, China
| | - Yongkang Xue
- Henan Dairy Herd Improvement Center, Zhengzhou, Henan 450045, China
| | - Yingyu Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; National Professional Laboratory For Animal Tuberculosis (Wuhan) of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Hubei Hongshan Laboratory, Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei 430070, China
| | - Ian D Robertson
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, Western Australia 6150, Australia; Hubei Hongshan Laboratory, Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei 430070, China
| | - Aizhen Guo
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; National Professional Laboratory For Animal Tuberculosis (Wuhan) of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Hubei Hongshan Laboratory, Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei 430070, China.
| | - Joshua Aleri
- School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, Western Australia 6150, Australia; Centre for Animal Production and Health, Future Foods Institute, Murdoch University, Western Australia 6150, Australia.
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Almaw G, Conlan AJK, Ameni G, Gumi B, Alemu A, Guta S, Gebre S, Olani A, Garoma A, Shegu D, Yimesgen L, Nigussie D, Wood JLN, Abebe T, Mihret A, Berg S. The variable prevalence of bovine tuberculosis among dairy herds in Central Ethiopia provides opportunities for targeted intervention. PLoS One 2021; 16:e0254091. [PMID: 34214106 PMCID: PMC8253440 DOI: 10.1371/journal.pone.0254091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 06/19/2021] [Indexed: 02/04/2023] Open
Abstract
Bovine tuberculosis (bTB) is an important disease for dairy productivity, as well as having the potential for zoonotic transmission. Previous prevalence studies of bTB in the dairy sector in central Ethiopia have suggested high prevalence, however, they have been limited to relatively small scale surveys, raising concerns about their representativeness. Here we carried out a cross sectional one-stage cluster sampling survey taking the dairy herd as a cluster to estimate the prevalence of bTB in dairy farms in six areas of central Ethiopia. The survey, which to date is by far the largest in the area in terms of the number of dairy farms, study areas and risk factors explored, took place from March 2016 to May 2017. This study combined tuberculin skin testing and the collection of additional herd and animal level data by questionnaire to identify potential risk factors contributing to bTB transmission. We applied the single intradermal cervical comparative tuberculin (SICCT) test using >4mm cut-off for considering an individual animal as positive for bTB; at least one reactor animal was required for a herd to be considered bTB positive. Two hundred ninety-nine dairy herds in the six study areas were randomly selected, from which 5,675 cattle were tested. The overall prevalence of bTB after standardisation for herd-size in the population was 54.4% (95% CI 48.7–60%) at the herd level, and it was 24.5% (95% CI 23.3–25.8) at the individual animal level. A Generalized Linear Mixed Model (GLMM) with herd and area as random effect was used to explore risk factors association with bTB status. We found that herd size, age, bTB history at farm, and breed were significant risk factors for animals to be SICCT positive. Animals from large herds had 8.3 times the odds of being tuberculin reactor (OR: 8.3, p-value:0.008) as compared to animals from small herds. The effect of age was strongest for animals 8–10 years of age (the oldest category) having 8.9 times the odds of being tuberculin reactors (OR: 8.9, p-value:<0.001) compared to the youngest category. The other identified significant risk factors were bTB history at farm (OR: 5.2, p-value:0.003) and cattle breed (OR: 2.5, p-value: 0.032). Our study demonstrates a high prevalence of bTB in central Ethiopia but with a large variation in within-herd prevalence between herds, findings that lays an important foundation for the future development of control strategies.
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Grants
- D43 TW009127 FIC NIH HHS
- Medical Research Council
- Biotechnology and Biological Sciences Research Council
- This research was financially supported by the Ethiopia Control of Bovine Tuberculosis Strategies (ETHICOBOTS) project funded by the Biotechnology and Biological Sciences Research Council, the Department for International Development, the Economic & Social Research Council, the Medical Research Council, the Natural Environment Research Council and the Defence Science &Technology Laboratory, under the Zoonoses and Emerging Livestock Systems (ZELS) program.Stefan Berg was also funded by Defra, United Kingdom, ref: TBSE3294. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
- ETHICOBOTS
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Affiliation(s)
- Gizat Almaw
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
- Department of Microbiology, Immunology and Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
- * E-mail:
| | - Andrew J. K. Conlan
- Disease Dynamics Unit, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Gobena Ameni
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- Department of Veterinary Medicine, College of Food and Agriculture, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Balako Gumi
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Alemseged Alemu
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Sintayehu Guta
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Solomon Gebre
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Abebe Olani
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Abebe Garoma
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Dereje Shegu
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Letebrhan Yimesgen
- National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia
| | - Demeke Nigussie
- Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - James L. N. Wood
- Disease Dynamics Unit, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Tamrat Abebe
- Department of Microbiology, Immunology and Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Adane Mihret
- Department of Microbiology, Immunology and Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Stefan Berg
- Bacteriology Department, Animal and Plant Health Agency, Weybridge, United Kingdom
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Campbell Z, Coleman P, Guest A, Kushwaha P, Ramuthivheli T, Osebe T, Perry B, Salt J. Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys. Prev Vet Med 2021; 189:105279. [PMID: 33581421 PMCID: PMC8024747 DOI: 10.1016/j.prevetmed.2021.105279] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/18/2020] [Accepted: 01/18/2021] [Indexed: 12/15/2022]
Abstract
Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.
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Affiliation(s)
- Zoë Campbell
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya.
| | - Paul Coleman
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Andrea Guest
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Peetambar Kushwaha
- GALVmed Asia Office, Unit 118 & 120 B, Splendor Forum, Plot No 3, Jasola District Centre, Jasola, New Delhi, 110025, India
| | - Thembinkosi Ramuthivheli
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Tom Osebe
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Brian Perry
- Nuffield College of Clinical Medicine, University of Oxford, United Kingdom; College of Medicine and Veterinary Medicine, University of Edinburgh, Arthurstone House, Meigle, Blairgowrie, PH12 8QW, Scotland, United Kingdom
| | - Jeremy Salt
- GALVmed UK Office, Doherty Building, Pentlands Science Park, Bush Loan, Penicuik Edinburgh, EH26 0PZ, Scotland, United Kingdom
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Occupational exposure and challenges in tackling M. bovis at human-animal interface: a narrative review. Int Arch Occup Environ Health 2021; 94:1147-1171. [PMID: 33725176 PMCID: PMC7961320 DOI: 10.1007/s00420-021-01677-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 01/12/2021] [Indexed: 01/09/2023]
Abstract
Zoonotic tuberculosis caused by Mycobacterium bovis (M. bovis), a member of Mycobacterium tuberculosis complex (MTBC) has increasingly gathered attention as a public health risk, particularly in developing countries with higher disease prevalence. M. bovis is capable of infecting multiple hosts encompassing a number of domestic animals, in particular cattle as well as a broad range of wildlife reservoirs. Humans are the incidental hosts of M. bovis whereby its transmission to humans is primarily through the consumption of cattle products such as unpasteurized milk or raw meat products that have been contaminated with M. bovis or the transmission could be due to close contact with infected cattle. Also, the transmission could occur through aerosol inhalation of infective droplets or infected body fluids or tissues in the presence of wound from infected animals. The zoonotic risk of M. bovis in humans exemplified by miscellaneous studies across different countries suggested the risk of occupational exposure towards M. bovis infection, especially those animal handlers that have close and unreserved contact with cattle and wildlife populations These animal handlers comprising of livestock farmers, abattoir workers, veterinarians and their assistants, hunters, wildlife workers as well as other animal handlers are at different risk of contracting M. bovis infection, depending on the nature of their jobs and how close is their interaction with infected animals. It is crucial to identify the underlying transmission risk factors and probable transmission pathways involved in the zoonotic transmission of M. bovis from animals to humans for better designation and development of specific preventive measures and guidelines that could reduce the risk of transmission and to protect these different occupational-related/populations at risk. Effective control and disease management of zoonotic tuberculosis caused by M. bovis in humans are also hindered by various challenges and factors involved at animal–human interface. A closer look into factors affecting proper disease control and management of M. bovis are therefore warranted. Hence, in this narrative review, we have gathered a number of different studies to highlight the risk of occupational exposure to M. bovis infection and addressed the limitations and challenges underlying this context. This review also shed lights on various components and approaches in tackling M. bovis infection at animal–human interface.
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Callaby R, Kelly R, Mazeri S, Egbe F, Benedictus L, Clark E, Doeschl-Wilson A, Bronsvoort B, Salavati M, Muwonge A. Genetic Diversity of Cameroon Cattle and a Putative Genomic Map for Resistance to Bovine Tuberculosis. Front Genet 2020; 11:550215. [PMID: 33281865 PMCID: PMC7705233 DOI: 10.3389/fgene.2020.550215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 10/19/2020] [Indexed: 11/30/2022] Open
Abstract
Bovine Tuberculosis (bTB) caused by Mycobacterium bovis is a livestock disease of global economic and public health importance. There are currently no effective vaccines available for livestock and so control relies on animal level surveillance and pasteurization of dairy products. A new alternative control approach is to exploit the genetic variability of the host; recent studies have demonstrated that breeding European taurine cattle, such as Holsteins for increased resistance to bTB is feasible. The utility of such an approach is still unknown for African cattle populations. This study aims to assess genetic variation in bTB resistance and the underlying genomic architecture of cattle in Cameroon. We conducted a cross-sectional study of 2,346 slaughter cattle in Cameroon. Retropharyngeal lymph node samples were collected and cultured on Lowenstein Jensen media and the BACTEC MGIT 960 system, and M. bovis was identified using the Hain® Genotype kits. A total of 153 cattle were positive for M. bovis and were archived along with a random selection of negative samples. In this study, we genotyped archived samples from 212 cattle. Their genomic diversity was characterized using PCA, hierarchical clustering and admixture analysis. We assessed genetic variation in bTB resistance using heritability analysis and compared quantitative trait loci. Previous research on this study population have shown that Fulani cattle are more susceptible to bTB than mixed breeds. However, here we show that these apparent phenotypic differences in breeds are not reflected by clear genomic differences. At the genetic level, both the Fulani and mixed cattle show similar patterns of admixture with evidence of both taurine and indicine ancestry. There was little European taurine introgression within the studied population. Hierarchical clustering showed clusters of cattle that differed in their susceptibility to bTB. Our findings allude to bTB resistance being polygenic in nature. This study highlights the potential for genetic control of bTB in Africa and the need for further research into the genetics of bTB resistance within African cattle populations.
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Affiliation(s)
- Rebecca Callaby
- Centre for Tropical Livestock Genetics and Health, The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.,The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Robert Kelly
- The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Stella Mazeri
- The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Franklyn Egbe
- School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Lindert Benedictus
- The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Emily Clark
- Centre for Tropical Livestock Genetics and Health, The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.,The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrea Doeschl-Wilson
- The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Barend Bronsvoort
- Centre for Tropical Livestock Genetics and Health, The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.,The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Mazdak Salavati
- Centre for Tropical Livestock Genetics and Health, The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.,The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Adrian Muwonge
- The Royal (Dick) School of Veterinary Studies, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
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