1
|
Cinar MU, Oliveira RD, Hadfield TS, Lichtenwalner A, Brzozowski RJ, Settlemire CT, Schoenian SG, Parker C, Neibergs HL, Cockett NE, White SN. Genome-wide association with footrot in hair and wool sheep. Front Genet 2024; 14:1297444. [PMID: 38288162 PMCID: PMC10822918 DOI: 10.3389/fgene.2023.1297444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 12/31/2023] [Indexed: 01/31/2024] Open
Abstract
Ovine footrot is an infectious disease with important contributions from Dichelobacter nodosus and Fusobacterium necrophorum. Footrot is characterized by separation of the hoof from underlying tissue, and this causes severe lameness that negatively impacts animal wellbeing, growth, and profitability. Large economic losses result from lost production as well as treatment costs, and improved genetic tools to address footrot are a valuable long-term goal. Prior genetic studies had examined European wool sheep, but hair sheep breeds such as Katahdin and Blackbelly have been reported to have increased resistance to footrot, as well as to intestinal parasites. Thus, footrot condition scores were collected from 251 U.S. sheep including Katahdin, Blackbelly, and European-influenced crossbred sheep with direct and imputed genotypes at OvineHD array (>500,000 single nucleotide polymorphism) density. Genome-wide association was performed with a mixed model accounting for farm and principal components derived from animal genotypes, as well as a random term for the genomic relationship matrix. We identified three genome-wide significant associations, including SNPs in or near GBP6 and TCHH. We also identified 33 additional associated SNPs with genome-wide suggestive evidence, including a cluster of 6 SNPs in a peak near the genome-wide significance threshold located near the glutamine transporter gene SLC38A1. These findings suggest genetic susceptibility to footrot may be influenced by genes involved in divergent biological processes such as immune responses, nutrient availability, and hoof growth and integrity. This is the first genome-wide study to investigate susceptibility to footrot by including hair sheep and also the first study of any kind to identify multiple genome-wide significant associations with ovine footrot. These results provide a foundation for developing genetic tests for marker-assisted selection to improve resistance to ovine footrot once additional steps like fine mapping and validation are complete.
Collapse
Affiliation(s)
- Mehmet Ulas Cinar
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
- Department of Animal Science, Faculty of Agriculture, Erciyes University, Kayseri, Turkiye
| | - Ryan D. Oliveira
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| | - Tracy S. Hadfield
- Department of Animal, Agricultural Experiment Station, Dairy and Veterinary Sciences, Utah State University, Logan, UT, United States
| | - Anne Lichtenwalner
- School of Food and Agriculture, University of Maine, Orono, ME, United States
- Cooperative Extension, University of Maine, Orono, ME, United States
| | | | | | - Susan G. Schoenian
- Western Maryland Research and Education Center, University of Maryland, College Park, MD, United States
| | - Charles Parker
- Department of Animal Sciences, Professor Emeritus, The Ohio State University, Columbus, OH, United States
| | - Holly L. Neibergs
- Department of Animal Science, Washington State University, Pullman, WA, United States
| | - Noelle E. Cockett
- Department of Animal, Agricultural Experiment Station, Dairy and Veterinary Sciences, Utah State University, Logan, UT, United States
| | - Stephen N. White
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
- Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, United States
- Center for Reproductive Biology, Washington State University, Pullman, WA, United States
| |
Collapse
|
2
|
Loosli N, Brodard I, Kittl S, Luyet C, Kuhnert P. Field validation of an antibiotic-free hoof spray to effectively treat ovine footrot by eliminating virulent Dichelobacter nodosus. Vet Microbiol 2023; 287:109920. [PMID: 38006721 DOI: 10.1016/j.vetmic.2023.109920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/02/2023] [Accepted: 11/19/2023] [Indexed: 11/27/2023]
Abstract
Ovine footrot caused by Dichelobacter nodosus is a highly contagious hoof disease negatively impacting animal welfare and causing major economic losses to the sheep industry. Bactericidal footbaths have shown to be an efficient treatment option and will be used in the national footrot control program in Switzerland. However, the application of footbaths is laborious and economically not sound for small flock holders. We therefore tested in a field study the Intra Repiderma spray for its applicability and efficacy to treat ovine footrot. Ten independent flocks fulfilling defined parameters (e.g. clinical signs, positive for D. nodosus, flock size) could be identified and were included in the study. Farms were visited weekly to fortnightly and clinical scores and swabs for D. nodosus real-time (rt)PCR were taken. Treatment with the Intra Repiderma spray was started after initial claw trimming at the very first visit and was carried out three times within a week. Clearly visible clinical improvement was evident after one week of treatment. Virulent D. nodosus amounts on feet declined constantly during treatment which was continued until all sheep of a flock tested rtPCR-negative (1-10 weeks). Results indicate that a highly effective improvement of clinical signs and complete elimination of virulent D. nodosus can be achieved with the spray treatment. Therefore, it is a valuable alternative to cumbersome footbaths especially for small flocks. A sustainable control of footrot and its pathogen in a successfully treated flock can be maintained by strict biosecurity measures and continued treatment as far as necessary.
Collapse
Affiliation(s)
- Nadia Loosli
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Isabelle Brodard
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Sonja Kittl
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Camille Luyet
- Federal Food Safety and Veterinary Office FSVO, Schwarzenburgstrasse 155, 3003 Bern, Switzerland
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland.
| |
Collapse
|
3
|
Blanchard AM, Baumbach CM, Michler JK, Pickwell ND, Staley CE, Franklin JM, Wattegedera SR, Entrican G, Tötemeyer S. Natural Mycoplasma Infection Reduces Expression of Pro-Inflammatory Cytokines in Response to Ovine Footrot Pathogens. Animals (Basel) 2022; 12:ani12233235. [PMID: 36496756 PMCID: PMC9737833 DOI: 10.3390/ani12233235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/10/2022] [Accepted: 11/18/2022] [Indexed: 11/24/2022] Open
Abstract
Ovine footrot is a complex multifactorial infectious disease, causing lameness in sheep with major welfare and economic consequences. Dichelobacter nodosus is the main causative bacterium; however, footrot is a polymicrobial disease with Fusobacterium necrophorum, Mycoplasma fermentans and Porphyromonas asaccharolytica also associated. There is limited understanding of the host response involved. The proinflammatory mediators, interleukin (IL)-1β and C-X-C Motif Chemokine Ligand 8 (CXCL8), have been shown to play a role in the early response to D. nodosus in dermal fibroblasts and interdigital skin explant models. To further understand the response of ovine skin to bacterial stimulation, and to build an understanding of the role of the cytokines and chemokines identified, primary ovine interdigital fibroblasts and keratinocytes were isolated, cultured and stimulated. The expression of mRNA and protein release of CXCL8 and IL-1β were measured after stimulation with LPS, D. nodosus or F. necrophorum, which resulted in increased transcript levels of IL-1β and CXCL8 in the M. fermentans-free cells. However, only an increase in the CXCL8 protein release was observed. No IL-1β protein release was detected, despite increases in IL-1β mRNA, suggesting the signal for intracellular pre-IL-1β processing may be lacking when culturing primary cells in isolation. The keratinocytes and fibroblasts naturally infected with M. fermentans showed little response to the LPS, a range of D. nodosus preparations or heat-inactivated F. necrophorum. Primary single cell culture models complement ex vivo organ culture models to study different aspects of the host response to D. nodosus. The ovine keratinocytes and fibroblasts infected with M. fermentans had a reduced response to the experimental bacterial stimulation. However, in the case of footrot where Mycoplasma spp. are associated with diseased feet, this natural infection gives important insights into the impact of multiple pathogens on the host response.
Collapse
Affiliation(s)
- Adam M. Blanchard
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
- Correspondence: (A.M.B.); (S.T.)
| | - Christina-Marie Baumbach
- Institute of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, Leipzig University, 04103 Leipzig, Germany
| | - Jule K. Michler
- Institute of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, Leipzig University, 04103 Leipzig, Germany
| | - Natalie D. Pickwell
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Ceri E. Staley
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Jemma M. Franklin
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Sean R. Wattegedera
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK
| | - Gary Entrican
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK
- The Roslin Institute, The University of Edinburgh, Easter Bush, Roslin EH25 9RG, UK
| | - Sabine Tötemeyer
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
- Correspondence: (A.M.B.); (S.T.)
| |
Collapse
|
4
|
Alsaaod M, Weber J, Jensen T, Brandt S, Gurtner C, Devaux D, Studer E, Steiner A. “Non-healing” claw horn lesions in dairy cows: Clinical, histopathological and molecular biological characterization of four cases. Front Vet Sci 2022; 9:1041215. [PMID: 36337205 PMCID: PMC9627347 DOI: 10.3389/fvets.2022.1041215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 09/26/2022] [Indexed: 11/28/2022] Open
Abstract
The increasing prevalence of bovine digital dermatitis (BDD) contributes to a higher occurrence of secondary infections of exposed corium with Treponema spp. in bovine claws. “Non-healing” claw horn lesions (NHL) clinically resemble BDD lesions. They are severe, cause chronic lameness, and may persist for several months. They poorly respond to standard treatments of BDD and represent a serious welfare issue. In this study, four cases of NHL were classified clinically either as BDD-associated axial horn fissures (BDD-HFA; n = 3) or BDD-associated sole ulcer (BDD-SU; n = 1). In all four cases, pronounced multifocal keratinolysis of the stratum corneum, ulceration, and severe chronic lymphoplasmacytic perivascular to interstitial dermatitis were observed. All lesional samples tested positive for Treponema spp., Fusobacterium (F.) necrophorum, and Porphyromonas (P.) levii by PCRs. BDD-HFA lesions contained Treponema pedis as revealed by genetic identities of 93, 99, and 100%. Treponemes in the BDD-SU lesion were 94% homologous to Treponema phylotype PT3. Fluorescent in situ hybridization (FISH) revealed extensive epidermal infiltration by treponemes that made up > 90% of the total bacterial population in all four lesions. FISH also tested positive for P. levii and negative for F. necrophorum in all four cases, whilst only one BDD-HFA contained Dichelobacter nodosus. Our data point to BDD-associated treponemes and P. levii constituting potential etiological agents in the development of “non-healing” claw horn lesions in cattle.
Collapse
Affiliation(s)
- Maher Alsaaod
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- *Correspondence: Maher Alsaaod
| | - Jim Weber
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Tim Jensen
- Center for Diagnostic, Technical University of Denmark, Kongens Lyngby, Denmark
- Section for Pathobiological Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sabine Brandt
- Research Group Oncology, Equine Clinic of Surgery, Department of Companion Animals and Horses, University of Veterinary Medicine, Vienna, Austria
| | - Corinne Gurtner
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, Institute of Animal Pathology, University of Bern, Bern, Switzerland
| | - David Devaux
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Department of Farm Animals, Vetsuisse Faculty, University of Zurich, Zürich, Switzerland
| | - Eveline Studer
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| |
Collapse
|
5
|
Clifton R, Monaghan EM, Green MJ, Purdy KJ, Green LE. Differences in composition of interdigital skin microbiota predict sheep and feet that develop footrot. Sci Rep 2022; 12:8931. [PMID: 35624131 PMCID: PMC9142565 DOI: 10.1038/s41598-022-12772-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/12/2022] [Indexed: 11/29/2022] Open
Abstract
Footrot has a major impact on health and productivity of sheep worldwide. The current paradigm for footrot pathogenesis is that physical damage to the interdigital skin (IDS) facilitates invasion of the essential pathogen Dichelobacter nodosus. The composition of the IDS microbiota is different in healthy and diseased feet, so an alternative hypothesis is that changes in the IDS microbiota facilitate footrot. We investigated the composition and diversity of the IDS microbiota of ten sheep, five that did develop footrot and five that did not (healthy) at weekly intervals for 20 weeks. The IDS microbiota was less diverse on sheep 2 + weeks before they developed footrot than on healthy sheep. This change could be explained by only seven of > 2000 bacterial taxa detected. The incubation period of footrot is 8–10 days, and there was a further reduction in microbial diversity on feet that developed footrot in that incubation period. We conclude that there are two stages of dysbiosis in footrot: the first predisposes sheep to footrot and the second occurs in feet during the incubation of footrot. These findings represent a step change in our understanding of the role of the IDS microbiota in footrot pathogenesis.
Collapse
Affiliation(s)
- Rachel Clifton
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, UK.
| | - Emma M Monaghan
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, UK
| | - Martin J Green
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Leicestershire, UK
| | - Kevin J Purdy
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Laura E Green
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, UK
| |
Collapse
|
6
|
Prevalence of bacterial species associated with ovine footrot and contagious ovine digital dermatitis in Swedish slaughter lambs. Acta Vet Scand 2022; 64:6. [PMID: 35264235 PMCID: PMC8905903 DOI: 10.1186/s13028-022-00625-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/20/2022] [Indexed: 11/10/2022] Open
Abstract
Background Ovine footrot and contagious ovine digital dermatitis (CODD) are contagious mixed bacterial infections with major impacts on animal health and production. In Sweden, ovine footrot and CODD were first detected in 2004 and 2019, respectively. In 2009, a voluntary control programme for footrot was established, and a prevalence study in slaughter lambs was conducted, however, the distribution of footrot and CODD-associated bacteria is still unknown. This study examined the prevalence of Dichelobacter nodosus, Fusobacterium necrophorum and Treponema spp., as well as the current prevalence of footrot and CODD, in Swedish slaughter lambs. Results A total of 2048 feet, from 512 slaughter lambs, were collected from eight slaughterhouses throughout Sweden in autumn 2020. All feet were visually examined for lesions of footrot and CODD and sampled for subsequent real-time polymerase chain reaction (PCR) analysis. Nine lambs (1.8%) had at least one foot affected with footrot (footrot score ≥ 2). A CODD grade 1 lesion was detected in a single lamb (0.2%). The prevalence of D. nodosus, F. necrophorum and Treponema spp. was 6.1%, 7.6% and 90.6%, respectively. The D. nodosus detected were benign strains. Conclusions The prevalence of footrot in Swedish slaughter lambs has been significantly reduced, from 5.8 to 1.8%, during the past 11 years. This indicates that preventive measures, such as the national control programme and elimination of footrot from affected flocks, have been effective. A single lamb (0.2%) was found with a CODD lesion (grade 1). In Sweden, benign rather than virulent strains of D. nodosus seem to be the most common. Neither D. nodosus nor F. necrophorum were widespread among Swedish slaughter lambs, but both were more likely to be found in lambs with footrot. Treponema spp. was very commonly found in lambs with and without footrot, but there is a lack of information on the individual Treponema spp. present in Swedish slaughter lambs and their potential pathogenicity.
Collapse
|
7
|
Hoby S, Jensen TK, Brodard I, Gurtner C, Eicher R, Steiner A, Kuhnert P, Alsaaod M. Detection of treponemes in digital dermatitis lesions of captive European bison (Bison bonasus). PLoS One 2021; 16:e0255921. [PMID: 34370779 PMCID: PMC8352065 DOI: 10.1371/journal.pone.0255921] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 07/26/2021] [Indexed: 11/19/2022] Open
Abstract
A newly-discovered foot disease of unknown origin in captive European Bison (Bison bonasus) was recently detected at Berne Animal Park. Dermatitis of the interdigital cleft of varying degrees of severity was diagnosed in all animals (n = 10). The aim of this study was to describe the gross and histological lesions of the interdigital cleft found in 10 captive European bison and to identify involved potential pathogens in affected feet using molecular-based methods for Treponema spp., Dichelobacter nodosus and Fusobacterium necrophorum. Lesions were scored according to the degree of gross pathology at limb level. In a single animal, the gross lesions were restricted to focal lesions on the dorsal aspect of the digital skin of each foot (score 1), whereas all other animals showed at least one foot with extended lesions including the interdigital cleft (score 2). The presence of viable spirochaetes was observed in all animals using dark field microscopy. Applying fluorescence in situ hybridisation (FISH) on biopsies, Treponema spp. were identified, infiltrating the skin lesions in varying numbers in nine animals. Nested PCRs for Treponema medium, Treponema phagedenis and Treponema pedis of swab samples showed three positive animals out of ten for the latter two, whereas pooled biopsy samples were positive in all ten animals for at least T. phagedenis (9/10) and/or T. pedis (7/10), while all samples were negative for T. medium. However, none of these Treponema species could be isolated and sequence analysis of the amplified products showed 100% match of 365 base pairs (bp) to Treponema phylotype PT3 and almost full match (530 of 532 bp, 99.6%) to Treponema phylotype PT13. The presence of T. phagedenis, PT3 and PT13 phylotypes was confirmed by FISH analyses. The phylotypes of T. phagedenis were present in all hybridized positive biopsies of Treponema spp., and PT13 and PT3 were less abundant. Neither D. nodosus nor F. necrophorum were detected. The histological Treponema score was mostly mild. Digital dermatitis in captive European Bison is contagious and differs from bovine digital dermatitis, concerning associated pathogens as well as gross appearance.
Collapse
Affiliation(s)
| | - Tim K. Jensen
- Center for Diagnostic, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Isabelle Brodard
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Corinne Gurtner
- Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Richard Eicher
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Maher Alsaaod
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- * E-mail:
| |
Collapse
|
8
|
OCCURRENCE OF FOOTROT IN FREE-RANGING ALPINE IBEX (CAPRA IBEX) COLONIES IN SWITZERLAND. J Wildl Dis 2021; 57:327-337. [PMID: 33822150 DOI: 10.7589/jwd-d-20-00050] [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: 04/03/2020] [Accepted: 10/09/2020] [Indexed: 11/20/2022]
Abstract
Footrot is a worldwide economically important, debilitating disease caused by Dichelobacter nodosus. In sheep (Ovis aries), it is characterized by lesions of varying severity, depending on the strain, whereas Alpine ibex (Capra ibex) seem to develop severe lesions, whatever the strain. Healthy carriers occur in livestock but are rare in wild ruminants. Using a triangulation approach (retrospective questionnaire survey, necropsy database screening, and pathogen prevalence estimation in selected ibex colonies with and without footrot), we aimed at evaluating the importance of footrot in the ibex population, identifying potential risk factors for disease occurrence in this species, and defining the epidemiological role of ibex. Our study revealed that footrot occurs throughout the entire ibex territory (34% of the Swiss ibex colonies affected) but only as a sporadic disease (mostly one case per disease event), although the situation differed among footrot-positive colonies because half of them had experienced outbreak recurrences. Risk factor analysis for the occurrence of footrot in ibex colonies suggested an absence of an effect of meteorologic conditions, region, contacts with sheep or cattle (known to be very common healthy carriers of D. nodosus) and existing local disease control program. We found a significant effect only of contacts with sheep having footrot. Pathogen prevalence was very low in all investigated colonies. In conclusion, our results support previous data suggesting that ibex are susceptible spillover hosts, likely infected mainly by sympatric sheep displaying clinical signs.
Collapse
|
9
|
Zanolari P, Dürr S, Jores J, Steiner A, Kuhnert P. Ovine footrot: A review of current knowledge. Vet J 2021; 271:105647. [PMID: 33840488 DOI: 10.1016/j.tvjl.2021.105647] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 02/17/2021] [Accepted: 02/18/2021] [Indexed: 12/14/2022]
Abstract
Footrot is a contagious foot disease mainly affecting sheep. It is caused by the Gram-negative anaerobic bacterium Dichelobacter nodosus. Warm, wet environmental conditions favour development of footrot, and under perfect conditions, it takes just 2-3 weeks from infection to manifestation of clinical signs. Affected sheep show lameness of various degrees and often graze while resting on their carpi. Local clinical signs vary in severity and extent from interdigital inflammation (benign footrot) to underrunning of the complete horn shoe in advanced stages of virulent footrot. Laboratory diagnosis ideally involves collection of four-foot interdigital swab samples followed by competitive real time PCR, allowing for detection of the presence of D. nodosus and differentiation between benign and virulent strains. Laboratory-based diagnostics at the flock level based on risk-based sampling and pooling of interdigital swab samples are recommended. The list of treatment options of individual sheep includes careful removal of the loose undermined horn, local or systemic administration of antimicrobials, systemic administration of non-steroidal anti-inflammatories (NSAIDs) and disinfectant footbathing. Strategies for control at the flock level are manifold and depend on the environmental conditions and the procedures traditionally implemented by the respective country. Generally, measures consist of treatment/culling of infected sheep, vaccination and prevention of reinfection of disease-free flocks. Gaining deeper insight into the beneficial effects of NSAIDs, screening for eco-friendly footbath solutions, developing better vaccines, including the development of a robust, reproducible infection model and elucidation of protective immune responses, as well as the elaboration of effective awareness training programs for sheep farmers, are relevant research gaps.
Collapse
Affiliation(s)
- Patrik Zanolari
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Salome Dürr
- Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Jörg Jores
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| |
Collapse
|
10
|
Giebel K, Green LE, Purdy KJ. A Pilot Study to Investigate the Feasibility of a Multiple Locus Variable Number Tandem Repeat Analysis to Understand the Epidemiology of Dichelobacter nodosus in Ovine Footrot. Front Vet Sci 2020; 7:581342. [PMID: 33344526 PMCID: PMC7738329 DOI: 10.3389/fvets.2020.581342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 11/09/2020] [Indexed: 11/13/2022] Open
Abstract
Dichelobacter nodosus is the essential pathogen in ovine footrot, an important cause of lameness in sheep that reduces productivity and welfare. The aim of this study was to investigate the feasibility of using multiple locus variable number tandem repeat analysis (MLVA) developed to investigate isolates to understand the molecular epidemiology of Dichelobacter nodosus in ovine footrot by investigation of communities of strains. MLVA sensitivity was improved by optimizing PCR conditions to 100% specificity for D. nodosus. The improved MLVA scheme was used to investigate non-cultured DNA purified from swabs (swab DNA) and cultured DNA from isolates (isolate DNA) from 152 foot and 38 gingival swab samples from 10 sheep sampled on four occasions in a longitudinal study. Isolate DNA was obtained from 6/152 (3.9%) feet and 5/6 yielded complete MLVA profiles, three strains were detected. Two of the three isolate strains were also detected in isolate DNA from 2 gingival crevice cultures. Complete MLVA profiles were obtained from swab DNA from 39 (25.7%) feet. There were 22 D. nodosus community types that were comprised of 7 single strain and 15 multi-strain communities. Six community types were detected more than once and three of these were detected on the same four sheep and the same two feet over time. There were a minimum of 17 and a maximum of 25 strain types of D. nodosus in the study. The three isolate strain types were also the most frequently detected strain types in swab DNA. We conclude that the MLVA from swab DNA detects the same strains as culture, is much more sensitive and can be used to describe and differentiate communities and strains on sheep, feet and over time. It is therefore a sensitive molecular tool to study D. nodosus strains directly from DNA without culture.
Collapse
Affiliation(s)
- Katharina Giebel
- School of Life Sciences, University of Warwick, Coventry, United Kingdom.,School of Agriculture, Food and the Environment, Royal Agricultural University, Gloucestershire, United Kingdom
| | - Laura E Green
- College of Life and Environmental Sciences, Institute for Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Kevin J Purdy
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| |
Collapse
|
11
|
Moore-Jones G, Ardüser F, Dürr S, Gobeli Brawand S, Steiner A, Zanolari P, Ryser-Degiorgis MP. Identifying maintenance hosts for infection with Dichelobacter nodosus in free-ranging wild ruminants in Switzerland: A prevalence study. PLoS One 2020; 15:e0219805. [PMID: 31917824 PMCID: PMC6952115 DOI: 10.1371/journal.pone.0219805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 12/16/2019] [Indexed: 12/14/2022] Open
Abstract
Footrot is a worldwide economically important, painful, contagious bacterial foot disease of domestic and wild ungulates caused by Dichelobacter nodosus. Benign and virulent strains have been identified in sheep presenting with mild and severe lesions, respectively. However, in Alpine ibex (Capra ibex ibex), both strains have been associated with severe lesions. Because the disease is widespread throughout sheep flocks in Switzerland, a nationwide footrot control program for sheep focusing on virulent strains shall soon be implemented. The aim of this cross-sectional study was to estimate the nationwide prevalence of both strain groups of D. nodosus in four wild indigenous ruminant species and to identify potential susceptible wildlife maintenance hosts that could be a reinfection source for domestic sheep. During two years (2017–2018), interdigital swabs of 1,821 wild indigenous ruminant species (Alpine ibex, Alpine chamois (Rupicapra rupicapra), roe deer (Capreolus capreolus), red deer (Cervus elaphus)) were analysed by Real-Time PCR. Furthermore, observed interspecies interactions were documented for each sample. Overall, we report a low prevalence of D. nodosus in all four indigenous wild ruminants, for both benign (1.97%, N = 36, of which 31 red deer) and virulent (0.05%, N = 1 ibex) strains. Footrot lesions were documented in one ibex with virulent strains, and in one ibex with benign strains. Interspecific interactions involving domestic livestock occurred mainly with cattle and sheep. In conclusion, the data suggest that wild ungulates are likely irrelevant for the maintenance and spread of D. nodosus. Furthermore, we add evidence that both D. nodosus strain types can be associated with severe disease in Alpine ibex. These data are crucial for the upcoming nationwide control program and reveal that wild ruminants should not be considered as a threat to footrot control in sheep in this context.
Collapse
Affiliation(s)
- Gaia Moore-Jones
- Centre for Fish and Wildlife Health, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Flurin Ardüser
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Salome Dürr
- Veterinary Public Health Institute, Vetsuisse-Faculty, University of Bern, Liebefeld, Switzerland
| | - Stefanie Gobeli Brawand
- Institute of Veterinary Bacteriology, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | - Patrik Zanolari
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bern, Switzerland
| | | |
Collapse
|
12
|
Sites of persistence of Fusobacterium necrophorum and Dichelobacter nodosus: a paradigm shift in understanding the epidemiology of footrot in sheep. Sci Rep 2019; 9:14429. [PMID: 31594981 PMCID: PMC6783547 DOI: 10.1038/s41598-019-50822-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 09/05/2019] [Indexed: 01/09/2023] Open
Abstract
Sites of persistence of bacterial pathogens contribute to disease dynamics of bacterial diseases. Footrot is a globally important bacterial disease that reduces health and productivity of sheep. It is caused by Dichelobacter nodosus, a pathogen apparently highly specialised for feet, while Fusobacterium necrophorum, a secondary pathogen in footrot is reportedly ubiquitous on pasture. Two prospective longitudinal studies were conducted to investigate the persistence of D. nodosus and F. necrophorum in sheep feet, mouths and faeces, and in soil. Molecular tools were used to detect species, strains and communities. In contrast to the existing paradigm, F. necrophorum persisted on footrot diseased feet, and in mouths and faeces; different strains were detected in feet and mouths. D. nodosus persisted in soil and on diseased, but not healthy, feet; similar strains were detected on both healthy and diseased feet of diseased sheep. We conclude that D. nodosus and F. necrophorum depend on sheep for persistence but use different strategies to persist and spread between sheep within and between flocks. Elimination of F. necrophorum would be challenging due to faecal shedding. In contrast D. nodosus could be eliminated if all footrot-affected sheep were removed and fade out of D. nodosus occurred in the environment before re-infection of a foot.
Collapse
|
13
|
Best N, Rodoni B, Rawlin G, Beddoe T. Evaluation of loop-mediated isothermal amplification (LAMP) assay for detection of aprV2 positive Dichelobacter nodosus in-field by secondary users. BMC Res Notes 2019; 12:534. [PMID: 31439030 PMCID: PMC6704695 DOI: 10.1186/s13104-019-4575-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/17/2019] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE Dichelobacter nodosus is the primary aetiological agent of footrot in sheep. Ovine footrot causes considerable economic losses and substantial animal welfare issues in the Australian sheep industry. Current methods for detecting D. nodosus are difficult, laborious and time-consuming. Recently, we developed a robust LAMP assay (VDN LAMP) that was able to identify aprV2 positive D. nodosus in-field. A major advantage of LAMP technology is the ability of the assay to be performed by non-specialists with minimal training. We aimed to assess the performance of the VDN LAMP in-field in comparison to a laboratory-based aprV2/aprB2 rtPCR when used by secondary users after training by the authors. RESULTS Two animal health officers (termed secondary users) from Department of Primary Industries and Regions, South Australia (PIRSA) were trained in the use of VDN LAMP, before carrying out in-field testing on several locations in South Australia. The performance of VDN LAMP assay by secondary user 1 was shown to successfully detect 73.91% (n = 53) aprV2 positive samples, while secondary user 2 detected 37.93% (n = 30) aprV2 positive samples. Overall, the ability to identify virulent D. nodosus by VDN LAMP by secondary users was mixed for various reasons, however, this could be rectified by additional training and commercial production of the LAMP kits to increase stability. We envisaged in the future VDN LAMP will able to be used by non-specialists to aid control programs.
Collapse
Affiliation(s)
- Nickala Best
- Department of Animal, Plant and Soil Science and Centre for AgriBioscience (AgriBio), La Trobe University, Bundoora, Melbourne, VIC, Australia
| | - Brendan Rodoni
- Department of Jobs, Precincts and Regions, Centre for AgriBioscience (AgriBio), Victorian Government, Bundoora, Melbourne, VIC, Australia
| | - Grant Rawlin
- Department of Jobs, Precincts and Regions, Centre for AgriBioscience (AgriBio), Victorian Government, Bundoora, Melbourne, VIC, Australia
| | - Travis Beddoe
- Department of Animal, Plant and Soil Science and Centre for AgriBioscience (AgriBio), La Trobe University, Bundoora, Melbourne, VIC, Australia.
| |
Collapse
|
14
|
Humbert MV, Jackson A, Orr CM, Tews I, Christodoulides M. Characterization of two putative Dichelobacter nodosus footrot vaccine antigens identifies the first lysozyme inhibitor in the genus. Sci Rep 2019; 9:10055. [PMID: 31296905 PMCID: PMC6624275 DOI: 10.1038/s41598-019-46506-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 06/24/2019] [Indexed: 12/17/2022] Open
Abstract
The Gram-negative anaerobic bacterium Dichelobacter nodosus (Dn) causes footrot in ruminants, a debilitating and highly contagious disease that results in necrotic hooves and significant economic losses in agriculture. Vaccination with crude whole-cell vaccine mixed with multiple recombinant fimbrial proteins can provide protection during species-specific outbreaks, but subunit vaccines containing broadly cross-protective antigens are desirable. We have investigated two D. nodosus candidate vaccine antigens. Macrophage Infectivity Potentiator Dn-MIP (DNO_0012, DNO_RS00050) and Adhesin Complex Protein Dn-ACP (DNO_0725, DNO_RS06795) are highly conserved amongst ~170 D. nodosus isolates in the https://pubmlst.org/dnodosus/ database. We describe the presence of two homologous ACP domains in Dn-ACP with potent C-type lysozyme inhibitor function, and homology of Dn-MIP to other putative cell-surface and membrane-anchored MIP virulence factors. Immunization of mice with recombinant proteins with a variety of adjuvants induced antibodies that recognised both proteins in D. nodosus. Notably, immunization with fimbrial-whole-cell Footvax vaccine induced anti-Dn-ACP and anti-Dn-MIP antibodies. Although all adjuvants induced high titre antibody responses, only antisera to rDn-ACP-QuilA and rDn-ACP-Al(OH)3 significantly prevented rDn-ACP protein from inhibiting lysozyme activity in vitro. Therefore, a vaccine incorporating rDn-ACP in particular could contribute to protection by enabling normal innate immune lysozyme function to aid bacterial clearance.
Collapse
Affiliation(s)
- Maria Victoria Humbert
- Neisseria Research Group, Molecular Microbiology, Academic Unit of Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, University of Southampton Faculty of Medicine, Southampton, United Kingdom
| | - Alexandra Jackson
- Neisseria Research Group, Molecular Microbiology, Academic Unit of Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, University of Southampton Faculty of Medicine, Southampton, United Kingdom
| | - Christian M Orr
- Beamline I23, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, United Kingdom
| | - Ivo Tews
- Biological Sciences, Institute for Life Sciences, B85 Highfield Campus, University of Southampton, Southampton, United Kingdom
| | - Myron Christodoulides
- Neisseria Research Group, Molecular Microbiology, Academic Unit of Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, University of Southampton Faculty of Medicine, Southampton, United Kingdom.
| |
Collapse
|
15
|
Ardüser F, Moore-Jones G, Gobeli Brawand S, Dürr S, Steiner A, Ryser-Degiorgis MP, Zanolari P. Dichelobacter nodosus in sheep, cattle, goats and South American camelids in Switzerland-Assessing prevalence in potential hosts in order to design targeted disease control measures. Prev Vet Med 2019; 178:104688. [PMID: 31109750 DOI: 10.1016/j.prevetmed.2019.05.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/29/2019] [Accepted: 05/02/2019] [Indexed: 10/26/2022]
Abstract
Footrot is a contagious foot disease caused by the bacterium Dichelobacter nodosus (D. nodosus) that affects sheep worldwide. Due to substantial economic and welfare impact, various countries have developed control programs against footrot. The aim of this cross-sectional study was to estimate the national prevalence of virulent and benign D. nodosus in Switzerland in the four domestic ruminant species sheep, cattle, goats and South American camelids (SAC) to detect potential host populations and to propose targeted disease control measures. Risk factors for infection with the virulent strain of D. nodosus, based on a survey carried out among farmers, were investigated on animal and herd level. Overall, 613 farms and 2920 animals were investigated during 2017-18 applying a two-stage cluster sampling strategy. A Real-Time PCR method for simultaneous detection of virulent and benign strains of D. nodosus was used for the first time in such a large study. On animal level, the true prevalence (TP) of virulent D. nodosus in sheep was estimated at 16.9% (95% confidence interval (CI95%): 9.5-24.3%). In cattle and goats no virulent D. nodosus was detected and in SAC an apparent prevalence (AP) of 0.2% (CI95%: 0.0-0.4%) was observed. On farm level, a TP of virulent D. nodosus of 16.2% (CI95%: 8.4-25.2%) for sheep and an AP of 1.5% (CI95%: 0.3-5.2%) for SAC herds was estimated. Since the Swiss control program only targets the virulent strains of D. nodosus, it was concluded that cattle, goats and SAC do not play a role in footrot epidemiology in Switzerland. Adult sheep were at higher risk of infection for virulent D. nodosus compared to lambs and yearlings. On herd level, risk factors for infection with virulent D. nodosus in sheep were earlier occurence of footrot, winter compared to summer and autumn, and goat contact on pasture. Liming pastures had a protective effect on D. nodosus infection. For benign D. nodosus, the TP in sheep was 6.3% (CI95%: 1.6-11.0%) and in cattle 88.4% (CI95%: 83.8-93.0%). The TP for benign D. nodosus in sheep farms was 2.8% (CI95%: 0.0-10.5%) and in cattle farms 95.9% (CI95%: 91.7-98.1%). In goat and SAC farms, the AP was 6.6% (CI95%: 3.4-11.5%) and 7.4% (CI95%: 3.8-13.1%), respectively. These findings could be relevant for wild ruminants such as Alpine ibex (Capra ibex ibex), which can develop clinical footrot after infection with benign D. nodosus. The findings of this study are crucial for assessing targeted disease control measures in Switzerland.
Collapse
Affiliation(s)
- Flurin Ardüser
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland
| | - Gaia Moore-Jones
- Centre for Fish and Wildlife Health (FIWI), Vetsuisse-Faculty, University of Bern, Länggassstrasse 122, Postfach, 3001 Bern, Switzerland
| | - Stefanie Gobeli Brawand
- Institute of Veterinary Bacteriology, Vetsuisse-Faculty, University of Bern, Länggassstrasse 122, Postfach, 3001 Bern, Switzerland
| | - Salome Dürr
- Veterinary Public Health Institute, Vetsuisse-Faculty, University of Bern, Schwarzenburgstrasse 155, 3097 Liebefeld, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland
| | - Marie-Pierre Ryser-Degiorgis
- Centre for Fish and Wildlife Health (FIWI), Vetsuisse-Faculty, University of Bern, Länggassstrasse 122, Postfach, 3001 Bern, Switzerland
| | - Patrik Zanolari
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland.
| |
Collapse
|
16
|
Potential transmission routes of Dichelobacter nodosus. Vet Microbiol 2018; 218:20-24. [PMID: 29685216 DOI: 10.1016/j.vetmic.2018.03.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/16/2018] [Accepted: 03/17/2018] [Indexed: 12/18/2022]
Abstract
Footrot caused by Dichelobacter nodosus is a highly contagious bacterial disease affecting the claw of sheep and the main cause of lameness in these animals. It is not only an economic burden but also a serious animal welfare issue. More information about the transmission of D. nodosus is needed for effective footrot control programs. We therefore determined the prevalence of D. nodosus in sheep presented at shows and markets where commingling of animals occurs. Furthermore, possible transmission vectors during foot trimming were investigated and trimming knife decontamination protocols evaluated. Sheep at six markets and four shows were sampled and tested for the presence of D. nodosus by real-time PCR. Different vectors, such as trimming knives were tested by real-time PCR and for viable D. nodosus by culture. The prevalence of virulent D. nodosus in sheep presented at shows and markets ranged from 1.7% to 100%. Regions with an ongoing control program showed significantly lower prevalence. After trimming, positive real-time PCR and culture results were obtained from the knives, the hands of the claw trimmers as well as removed claw horn material whereas boots were only positive by real-time PCR. In conclusion, markets and shows pose a risk for transmission of D. nodosus. The risk of transmission is particularly high during claw trimming and recommended measures to limit this risk include wiping the knife with a disinfection towel, wearing and changing gloves after every sheep, as well as proper disposal of trimmed and infectious horn.
Collapse
|
17
|
Best N, Gwozdz J, Suter R, Rawlin G, Beddoe T. Direct serogrouping of Dichelobacter nodosus from Victorian farms using conventional multiplex polymerase chain reaction. BMC Res Notes 2018; 11:108. [PMID: 29415761 PMCID: PMC5804069 DOI: 10.1186/s13104-018-3229-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 02/02/2018] [Indexed: 11/13/2022] Open
Abstract
Objective Dichelobacter nodosus is the causative agent of footrot in sheep. Ovine footrot is a major problem in Australia that results in large economic losses and a represents a very significant animal welfare issue. D. nodosus is divided into 10 serogroups (A–I, M), based on sequence variation in the type IV fimbriae gene, fimA. Control of the bacteria is possible through use of serogroup-specific vaccination, however traditional identification of the serogroups of D. nodosus on infected sheep is time-consuming and costly. With the aim of reducing time and cost, a PCR assay was used to identify serogroups of D. nodosus directly from foot swabs of infected sheep in Victoria. Results It was shown that serogroup B was most common (10 locations), followed by A, G and H (4 locations), I and C (2 locations), D, E and F (1 location). Infections with multiple serotypes were observed in 50% of farms, with the remaining 50% having only a single serogroup detected. The ability to identify serogroups quickly and cheaply direct from foot swabs will aid the understanding of the epidemiology of D. nodosus and support control programs. Electronic supplementary material The online version of this article (10.1186/s13104-018-3229-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Nickala Best
- Department of Animal, Plant and Soil Science and Centre for AgriBioscience (AgriBio), La Trobe University, Bundoora, Melbourne, VIC, Australia
| | - Jacek Gwozdz
- Department of Economic Development, Jobs, Transport and Resources Centre for AgriBioscience (AgriBio), Victorian Government, Bundoora, Melbourne, VIC, Australia
| | - Robert Suter
- Department of Economic Development, Jobs, Transport and Resources, Victorian Government, Attwood, Melbourne, VIC, Australia
| | - Grant Rawlin
- Department of Economic Development, Jobs, Transport and Resources Centre for AgriBioscience (AgriBio), Victorian Government, Bundoora, Melbourne, VIC, Australia
| | - Travis Beddoe
- Department of Animal, Plant and Soil Science and Centre for AgriBioscience (AgriBio), La Trobe University, Bundoora, Melbourne, VIC, Australia.
| |
Collapse
|
18
|
Zingg D, Steinbach S, Kuhlgatz C, Rediger M, Schüpbach-Regula G, Aepli M, Grøneng GM, Dürr S. Epidemiological and Economic Evaluation of Alternative On-Farm Management Scenarios for Ovine Footrot in Switzerland. Front Vet Sci 2017; 4:70. [PMID: 28560223 PMCID: PMC5432651 DOI: 10.3389/fvets.2017.00070] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 04/24/2017] [Indexed: 11/13/2022] Open
Abstract
Footrot is a multifactorial infectious disease mostly affecting sheep, caused by the bacteria Dichelobacter nodosus. It causes painful feet lesions resulting in animal welfare issues, weight loss, and reduced wool production, which leads to a considerable economic burden in animal production. In Switzerland, the disease is endemic and mandatory coordinated control programs exist only in some parts of the country. This study aimed to compare two nationwide control strategies and a no intervention scenario with the current situation, and to quantify their net economic effect. This was done by sequential application of a maximum entropy model (MEM), epidemiological simulation, and calculation of net economic effect using the net present value method. Building upon data from a questionnaire, the MEM revealed a nationwide footrot prevalence of 40.2%. Regional prevalence values were used as inputs for the epidemiological model. Under the application of the nationwide coordinated control program without (scenario B) and with (scenario C) improved diagnostics [polymerase chain reaction (PCR) test], the Swiss-wide prevalence decreased within 10 years to 14 and 5%, respectively. Contrary, an increase to 48% prevalence was observed when terminating the current control strategies (scenario D). Management costs included labor and material costs. Management benefits included reduction of fattening time and improved animal welfare, which is valued by Swiss consumers and therefore reduces societal costs. The net economic effect of the alternative scenarios B and C was positive, the one of scenario D was negative and over a period of 17 years quantified at CHF 422.3, 538.3, and -172.3 million (1 CHF = 1.040 US$), respectively. This implies that a systematic Swiss-wide management program under the application of the PCR diagnostic test is the most recommendable strategy for a cost-effective control of footrot in Switzerland.
Collapse
Affiliation(s)
- Dana Zingg
- Veterinary Public Health Institute, University of Bern, Bern, Switzerland
| | - Sandro Steinbach
- Center of Economic Research, Swiss Federal Institute of Technology in Zurich, Zurich, Switzerland
| | - Christian Kuhlgatz
- Agricultural Economics, Swiss Federal Institute of Technology in Zurich, Institute for Environmental Decisions (IED), Zurich, Switzerland
| | - Matthias Rediger
- Agricultural Economics, Swiss Federal Institute of Technology in Zurich, Institute for Environmental Decisions (IED), Zurich, Switzerland
| | | | - Matteo Aepli
- Agricultural Economics, Swiss Federal Institute of Technology in Zurich, Institute for Environmental Decisions (IED), Zurich, Switzerland
| | - Gry M Grøneng
- Norwegian Veterinary Institute, Oslo, Norway.,The Norwegian Institute of Public Health, Oslo, Norway
| | - Salome Dürr
- Veterinary Public Health Institute, University of Bern, Bern, Switzerland
| |
Collapse
|
19
|
Frosth S, König U, Nyman AK, Aspán A. Sample pooling for real-time PCR detection and virulence determination of the footrot pathogen Dichelobacter nodosus. Vet Res Commun 2017; 41:189-193. [PMID: 28343363 PMCID: PMC5547177 DOI: 10.1007/s11259-017-9686-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 03/15/2017] [Indexed: 10/25/2022]
Abstract
Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.
Collapse
Affiliation(s)
- Sara Frosth
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P. O. Box 7036, SE-750 07, Uppsala, Sweden. .,Department of Microbiology, National Veterinary Institute (SVA), SE-751 89, Uppsala, Sweden.
| | - Ulrika König
- Farm and Animal Health, Kungsängens gård, SE-753 23, Uppsala, Sweden
| | - Ann-Kristin Nyman
- Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute (SVA), SE-751 89, Uppsala, Sweden
| | - Anna Aspán
- Department of Microbiology, National Veterinary Institute (SVA), SE-751 89, Uppsala, Sweden
| |
Collapse
|
20
|
Zheng J, Sun L, Shu S, Zhu K, Xu C, Wang J, Wang H. Nuclear magnetic resonance-based serum metabolic profiling of dairy cows with footrot. J Vet Med Sci 2016; 78:1421-1428. [PMID: 27320815 PMCID: PMC5059369 DOI: 10.1292/jvms.15-0720] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Footrot is a debilitating and contagious disease in dairy cows, caused by the
Gram-negative anaerobe Dichelobacter nodosus. 1H-NMR (nuclear
magnetic resonance)-based metabolomics has been previously used to understand the
pathology and etiology of several diseases. The objective of this study was to
characterize serum from dairy cows with footrot (n=10) using 1H-NMR-based
metabolomics and chemometric analyses. 1H-NMR spectroscopy with multivariate
pattern recognition (principal component analysis and orthogonal partial least-squares
discriminant analysis) was performed to identify biomarkers in cows with footrot (F) and
healthy controls (C). 1H-NMR analysis facilitated the identification of 21
metabolites. Among these metabolites, 4 metabolites were higher and 17 metabolites were
lower in the F group than in the C group. The serum levels of 5 metabolites were
significantly different (P<0.05) between the two groups. The results
revealed that cows with footrot have altered carbohydrate, amino acid, lipid and energy
metabolic pathways. Metabolomic approaches are a clinically useful diagnostic tool for
understanding the biochemical alterations and mechanisms of several diseases.
Collapse
Affiliation(s)
- Jiasan Zheng
- College of Veterinary Medicine, Northeast Agricultural University, 59 Mucai Street, Harbin 150030, P.R. China
| | | | | | | | | | | | | |
Collapse
|
21
|
|
22
|
Genomic evidence for a globally distributed, bimodal population in the ovine footrot pathogen Dichelobacter nodosus. mBio 2014; 5:e01821-14. [PMID: 25271288 PMCID: PMC4196234 DOI: 10.1128/mbio.01821-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Footrot is a contagious, debilitating disease of sheep, causing major economic losses in most sheep-producing countries. The causative agent is the Gram-negative anaerobe Dichelobacter nodosus. Depending on the virulence of the infective bacterial strain, clinical signs vary from a mild interdigital dermatitis (benign footrot) to severe underrunning of the horn of the hoof (virulent footrot). The aim of this study was to investigate the genetic relationship between D. nodosus strains of different phenotypic virulences and between isolates from different geographic regions. Genome sequencing was performed on 103 D. nodosus isolates from eight different countries. Comparison of these genome sequences revealed that they were highly conserved, with >95% sequence identity. However, single nucleotide polymorphism analysis of the 31,627 nucleotides that were found to differ in one or more of the 103 sequenced isolates divided them into two distinct clades. Remarkably, this division correlated with known virulent and benign phenotypes, as well as with the single amino acid difference between the AprV2 and AprB2 proteases, which are produced by virulent and benign strains, respectively. This division was irrespective of the geographic origin of the isolates. However, within one of these clades, isolates from different geographic regions generally belonged to separate clusters. In summary, we have shown that D. nodosus has a bimodal population structure that is globally conserved and provide evidence that virulent and benign isolates represent two distinct forms of D. nodosus strains. These data have the potential to improve the diagnosis and targeted control of this economically significant disease. The Gram-negative anaerobic bacterium Dichelobacter nodosus is the causative agent of ovine footrot, a disease of major importance to the worldwide sheep industry. The known D. nodosus virulence factors are its type IV fimbriae and extracellular serine proteases. D. nodosus strains are designated virulent or benign based on the type of disease caused under optimal climatic conditions. These isolates have similar fimbriae but distinct extracellular proteases. To determine the relationship between virulent and benign isolates and the relationship of isolates from different geographical regions, a genomic study that involved the sequencing and subsequent analysis of 103 D. nodosus isolates was undertaken. The results showed that D. nodosus isolates are highly conserved at the genomic level but that they can be divided into two distinct clades that correlate with their disease phenotypes and with a single amino acid substitution in one of the extracellular proteases.
Collapse
|
23
|
Davenport R, Heawood C, Sessford K, Baker M, Baiker K, Blacklaws B, Kaler J, Green L, Tötemeyer S. Differential expression of Toll-like receptors and inflammatory cytokines in ovine interdigital dermatitis and footrot. Vet Immunol Immunopathol 2014; 161:90-8. [PMID: 25124770 PMCID: PMC4157958 DOI: 10.1016/j.vetimm.2014.07.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 06/27/2014] [Accepted: 07/17/2014] [Indexed: 10/29/2022]
Abstract
Footrot is a common inflammatory bacterial disease affecting the health and welfare of sheep worldwide. The pathogenesis of footrot is complex and multifactorial. The primary causal pathogen is the anaerobic bacterium Dichelobacter nodosus, with Fusobacterium necrophorum also shown to play a key role in disease. Since immune-mediated pathology is implicated, the aim of this research was to investigate the role of the host response in interdigital dermatitis (ID) and footrot. We compared the expression of Toll-like receptors (TLRs) and pro-inflammatory cytokines and the histological appearance of clinically normal in comparison to ID and footrot affected tissues. Severe ID and footrot were characterised by significantly increased transcript levels of pro-inflammatory cytokines TNFα and IL1β and the pattern recognition receptors TLR2 and TLR4 in the interdigital skin. This was reflected in the histopathological appearance, with ID and footrot presenting progressive chronic-active pododermatitis with a mixed lymphocytic and neutrophilic infiltration, gradually increasing from a mild form in clinically normal feet, to moderate in ID and to a focally severe form with frequent areas of purulence in footrot. Stimulation with F. necrophorum and/or D. nodosus extracts demonstrated that dermal fibroblasts, the resident cell type of the dermis, also contribute to the inflammatory response to footrot bacteria by increased expression of TNFα, IL1β and TLR2. Overall, ID and footrot lead to a local inflammatory response given that expression levels of TLRs and IL1β were dependent on the disease state of the foot not the animal.
Collapse
Affiliation(s)
- Rebecca Davenport
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Christopher Heawood
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Kate Sessford
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Melissa Baker
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Kerstin Baiker
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Barbara Blacklaws
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Jasmeet Kaler
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK
| | - Laura Green
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Sabine Tötemeyer
- School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK.
| |
Collapse
|
24
|
Gamithromycin plasma and skin pharmacokinetics in sheep. Res Vet Sci 2014; 97:199-203. [PMID: 25241389 DOI: 10.1016/j.rvsc.2014.08.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 08/25/2014] [Accepted: 08/26/2014] [Indexed: 11/23/2022]
Abstract
This study assessed the plasma kinetics and skin/plasma concentration ratio of the azalide antibiotic gamithromycin (ZACTRAN(®), Merial) in sheep after a single subcutaneous administration at 6 mg/kg bodyweight. Gamithromycin concentrations in plasma samples collected at various intervals up to 21 days following treatment and metacarpal skin obtained from animals at two, five and ten days after treatment were determined by liquid chromatography-tandem mass spectrometry methods. After administration, gamithromycin was rapidly absorbed, and individual maximum plasma concentrations were observed within 6 hours post-dose. Plasma peak concentration was 573 ± 168 ng/ml. The mean area under the plasma concentration versus time curve extrapolated to infinity was 8.00 ± 1.41 µg · hr/ml, and the mean terminal half-life was 34.5 ± 5.4 hours. Gamithromycin skin concentrations were much higher than the plasma concentrations resulting in skin/plasma concentration ratios of approximately 21, 58, and 138 at two, five and ten days post-dose, respectively, demonstrating extensive distribution to skin tissue.
Collapse
|
25
|
Forbes AB, Strobel H, Stamphoj I. Field studies on the elimination of footrot in sheep through whole flock treatments with gamithromycin. Vet Rec 2014; 174:146. [DOI: 10.1136/vr.102028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- A. B. Forbes
- Merial S.A.S; 29 Avenue Tony Garnier Lyon 69007 France
| | - H. Strobel
- Schafpraxis; Am Hopfenberg 8 Stoffenried D-89352 Germany
| | | |
Collapse
|
26
|
Simultaneous detection and discrimination of virulent and benign Dichelobacter nodosus in sheep of flocks affected by foot rot and in clinically healthy flocks by competitive real-time PCR. J Clin Microbiol 2014; 52:1228-31. [PMID: 24452162 DOI: 10.1128/jcm.03485-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ovine foot rot caused by Dichelobacter nodosus is affecting sheep worldwide. The current diagnostic methods are difficult and cumbersome. Here, we present a competitive real-time PCR based on allelic discrimination of the protease genes aprV2 and aprB2. This method allows direct detection and differentiation of virulent and benign D. nodosus from interdigital skin swabs in a single test. Clinically affected sheep harbored high loads of only virulent strains, whereas healthy sheep had lower loads of predominantly benign strains.
Collapse
|
27
|
Strobel H, Lauseker M, Forbes AB. Targeted antibiotic treatment of lame sheep with footrot using either oxytetracycline or gamithromycin. Vet Rec 2014; 174:46. [DOI: 10.1136/vr.101840] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- H. Strobel
- Schafpraxis; Am Hopfenberg 8 Stoffenried 89352 Germany
| | - M. Lauseker
- Institut für medizinische Informationsverarbeitung; Biometrie und Epidemiologie (IBE); Ludwig-Maximilians-Universität München; Munich Germany
| | - A. B. Forbes
- Merial SAS; 29 Avenue Tony Garnier Lyon 69007 France
| |
Collapse
|
28
|
Hall JA, Vorachek WR, Stewart WC, Gorman ME, Mosher WD, Pirelli GJ, Bobe G. Selenium supplementation restores innate and humoral immune responses in footrot-affected sheep. PLoS One 2013; 8:e82572. [PMID: 24340044 PMCID: PMC3855423 DOI: 10.1371/journal.pone.0082572] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 11/04/2013] [Indexed: 11/30/2022] Open
Abstract
Dietary selenium (Se) alters whole-blood Se concentrations in sheep, dependent upon Se source and dosage administered, but little is known about effects on immune function. We used footrot (FR) as a disease model to test the effects of supranutritional Se supplementation on immune function. To determine the effect of Se-source (organic Se-yeast, inorganic Na-selenite or Na-selenate) and Se-dosage (1, 3, 5 times FDA-permitted level) on FR severity, 120 ewes with and 120 ewes without FR were drenched weekly for 62 weeks with different Se sources and dosages (30 ewes/treatment group). Innate immunity was evaluated after 62 weeks of supplementation by measuring neutrophil bacterial killing ability. Adaptive immune function was evaluated by immunizing sheep with keyhole limpet hemocyanin (KLH). The antibody titer and delayed-type hypersensitivity skin test to KLH were used to assess humoral immunity and cell-mediated immunity, respectively. At baseline, FR-affected ewes had lower whole-blood and serum-Se concentrations; this difference was not observed after Se supplementation. Se supplementation increased neutrophil bacterial killing percentages in FR-affected sheep to percentages observed in supplemented and non-supplemented healthy sheep. Similarly, Se supplementation increased KLH antibody titers in FR-affected sheep to titers observed in healthy sheep. FR-affected sheep demonstrated suppressed cell-mediated immunity at 24 hours after intradermal KLH challenge, although there was no improvement with Se supplementation. We did not consistently prevent nor improve recovery from FR over the 62 week Se-treatment period. In conclusion, Se supplementation does not prevent FR, but does restore innate and humoral immune functions negatively affected by FR.
Collapse
Affiliation(s)
- Jean A. Hall
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
- * E-mail:
| | - William R. Vorachek
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
| | - Whitney C. Stewart
- Department of Animal and Rangeland Sciences, College of Agriculture, Oregon State University, Corvallis, Oregon, United States of America
- Current Address: Department of Animal and Range Sciences, New Mexico State University, Las Cruces, New Mexico, United States of America
| | - M. Elena Gorman
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
| | - Wayne D. Mosher
- Department of Animal and Rangeland Sciences, College of Agriculture, Oregon State University, Corvallis, Oregon, United States of America
| | - Gene J. Pirelli
- Department of Animal and Rangeland Sciences, College of Agriculture, Oregon State University, Corvallis, Oregon, United States of America
| | - Gerd Bobe
- Department of Animal and Rangeland Sciences, College of Agriculture, Oregon State University, Corvallis, Oregon, United States of America
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, United States of America
| |
Collapse
|
29
|
Stäuble A, Steiner A, Normand L, Kuhnert P, Frey J. Molecular genetic analysis of Dichelobacter nodosus proteases AprV2/B2, AprV5/B5 and BprV/B in clinical material from European sheep flocks. Vet Microbiol 2013; 168:177-84. [PMID: 24332828 DOI: 10.1016/j.vetmic.2013.11.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/01/2013] [Accepted: 11/09/2013] [Indexed: 10/26/2022]
Abstract
Dichelobacter nodosus, the etiological agent of ovine footrot, exists both as virulent and as benign strains, which differ in virulence mainly due to subtle differences in the three subtilisin-like proteases AprV2, AprV5 and BprV found in virulent, and AprB2, AprB5 and BprB in benign strains of D. nodosus. Our objective was a molecular genetic epidemiological analysis of the genes of these proteases by direct sequence analysis from clinical material of sheep from herds with and without history of footrot from 4 different European countries. The data reveal the two proteases known as virulent AprV2 and benign AprB2 to correlate fully to the clinical status of the individuals or the footrot history of the herd. In samples taken from affected herds, the aprV2 gene was found as a single allele whereas in samples from unaffected herds several alleles with minor modifications of the aprB2 gene were detected. The different alleles of aprB2 were related to the herds. The aprV5 and aprB5 genes were found in the form of several alleles scattered without distinction between affected and non-affected herds. However, all different alleles of aprV5 and aprB5 encode the same amino acid sequences, indicating the existence of a single protease isoenzyme 5 in both benign and virulent strains. The genes of the basic proteases BprV and BprB also exist as various alleles. However, differences found in samples from affected versus non-affected herds do not reflect the currently known epitopes that are attributed to differences in biochemical activity. The data of the study confirm the prominent role of AprV2 in the virulence of D. nodosus and shed a new light on the presence of the other protease genes and their allelic variants in clinical samples.
Collapse
Affiliation(s)
- Anna Stäuble
- Institute of Veterinary Bacteriology, Vetsuisse-Faculty, University of Bern, Postfach, Länggassstrasse 122, CH-3001 Bern, Switzerland; Clinic for Ruminants, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Postfach, Bremgartenstrasse 109a, CH-3001 Bern, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Department of Clinical Veterinary Medicine, Vetsuisse-Faculty, University of Bern, Postfach, Bremgartenstrasse 109a, CH-3001 Bern, Switzerland
| | - Lea Normand
- Institute of Veterinary Bacteriology, Vetsuisse-Faculty, University of Bern, Postfach, Länggassstrasse 122, CH-3001 Bern, Switzerland; University College of Northern Denmark, UCN, Aalborg, Denmark
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse-Faculty, University of Bern, Postfach, Länggassstrasse 122, CH-3001 Bern, Switzerland
| | - Joachim Frey
- Institute of Veterinary Bacteriology, Vetsuisse-Faculty, University of Bern, Postfach, Länggassstrasse 122, CH-3001 Bern, Switzerland.
| |
Collapse
|
30
|
Hugejiletu H, Bobe G, Vorachek WR, Gorman ME, Mosher WD, Pirelli GJ, Hall JA. Selenium supplementation alters gene expression profiles associated with innate immunity in whole-blood neutrophils of sheep. Biol Trace Elem Res 2013; 154:28-44. [PMID: 23754590 DOI: 10.1007/s12011-013-9716-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 05/23/2013] [Indexed: 01/12/2023]
Abstract
Footrot (FR) is a common, contagious bacterial disease of sheep that results in lameness and significant economic losses for producers. We previously reported that sheep affected with FR have lower whole-blood (WB) selenium (Se) concentrations and that Se supplementation in conjunction with routine control practices accelerates recovery from FR. To determine whether oral Se-yeast administered at supranutritional levels (>4.9 mg Se/week) alters the ability of sheep to resist or recover from FR infection, 60 ewes with and 60 ewes without FR were drenched once weekly for 62.5 weeks with 0, 4.9, 14.7, or 24.5 mg organic Se-yeast (30 ewes per treatment group). Footrot prevalence and severity were measured at 0, 20, 28, 40, and 60 weeks of Se supplementation. Genomic expression of eight WB-neutrophil genes for selenoproteins and seven WB-neutrophil genes for proteins involved in innate immunity was determined at the end of the treatment period using SYBR Green and quantitative polymerase chain reaction methodology. Supranutritional Se-yeast supplementation successfully increased Se status in sheep but did not prevent FR. Supranutritional Se-yeast supplementation increased WB-neutrophil expression of genes involved in innate immunity: L-selectin, interleukin-8 receptor, and toll-like receptor 4, which were or tended to be lower in ewes affected with FR. Furthermore, supranutritional Se-yeast supplementation altered the expression of selenoprotein genes involved in innate immunity, increasing selenoprotein S and glutathione peroxidase 4 and decreasing iodothyronine deiodinases 2 and 3. In conclusion, supranutritional Se-yeast supplementation does not prevent FR, but does alter WB-neutrophil gene expression profiles associated with innate immunity, including reversing those impacted by FR.
Collapse
Affiliation(s)
- Hugejiletu Hugejiletu
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA
| | | | | | | | | | | | | |
Collapse
|
31
|
Han X, Kennan RM, Rood JI. Serine proteases and ovine footrot. MICROBIOLOGY AUSTRALIA 2013. [DOI: 10.1071/ma13012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
32
|
Hartung S, Arvai AS, Wood T, Kolappan S, Shin DS, Craig L, Tainer JA. Ultrahigh resolution and full-length pilin structures with insights for filament assembly, pathogenic functions, and vaccine potential. J Biol Chem 2011; 286:44254-44265. [PMID: 22027840 PMCID: PMC3243539 DOI: 10.1074/jbc.m111.297242] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 10/10/2011] [Indexed: 11/06/2022] Open
Abstract
Pilin proteins assemble into Type IV pili (T4P), surface-displayed bacterial filaments with virulence functions including motility, attachment, transformation, immune escape, and colony formation. However, challenges in crystallizing full-length fiber-forming and membrane protein pilins leave unanswered questions regarding pilin structures, assembly, functions, and vaccine potential. Here we report pilin structures of full-length DnFimA from the sheep pathogen Dichelobacter nodosus and FtPilE from the human pathogen Francisella tularensis at 2.3 and 1 Å resolution, respectively. The DnFimA structure reveals an extended kinked N-terminal α-helix, an unusual centrally located disulfide, conserved subdomains, and assembled epitopes informing serogroup vaccines. An interaction between the conserved Glu-5 carboxyl oxygen and the N-terminal amine of an adjacent subunit in the crystallographic dimer is consistent with the hypothesis of a salt bridge between these groups driving T4P assembly. The FtPilE structure identifies an authentic Type IV pilin and provides a framework for understanding the role of T4P in F. tularensis virulence. Combined results define a unified pilin architecture, specialized subdomain roles in pilus assembly and function, and potential therapeutic targets.
Collapse
Affiliation(s)
- Sophia Hartung
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Andrew S Arvai
- Department of Molecular Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037
| | - Timothy Wood
- Department of Molecular Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037
| | - Subramaniapillai Kolappan
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - David S Shin
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Lisa Craig
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
| | - John A Tainer
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720; Department of Molecular Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037.
| |
Collapse
|
33
|
Wong W, Wijeyewickrema LC, Kennan RM, Reeve SB, Steer DL, Reboul C, Smith AI, Pike RN, Rood JI, Whisstock JC, Porter CJ. S1 pocket of a bacterially derived subtilisin-like protease underpins effective tissue destruction. J Biol Chem 2011; 286:42180-42187. [PMID: 21990366 DOI: 10.1074/jbc.m111.298711] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The ovine footrot pathogen, Dichelobacter nodosus, secretes three subtilisin-like proteases that play an important role in the pathogenesis of footrot through their ability to mediate tissue destruction. Virulent and benign strains of D. nodosus secrete the basic proteases BprV and BprB, respectively, with the catalytic domain of these enzymes having 96% sequence identity. At present, it is not known how sequence variation between these two putative virulence factors influences their respective biological activity. We have determined the high resolution crystal structures of BprV and BprB. These data reveal that that the S1 pocket of BprV is more hydrophobic but smaller than that of BprB. We show that BprV is more effective than BprB in degrading extracellular matrix components of the host tissue. Mutation of two residues around the S1 pocket of BprB to the equivalent residues in BprV dramatically enhanced its proteolytic activity against elastin substrates. Application of a novel approach for profiling substrate specificity, the Rapid Endopeptidase Profiling Library (REPLi) method, revealed that both enzymes prefer cleaving after hydrophobic residues (and in particular P1 leucine) but that BprV has more restricted primary substrate specificity than BprB. Furthermore, for P1 Leu-containing substrates we found that BprV is a significantly more efficient enzyme than BprB. Collectively, these data illuminate how subtle changes in D. nodosus proteases may significantly influence tissue destruction as part of the ovine footrot pathogenesis process.
Collapse
Affiliation(s)
- Wilson Wong
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Lakshmi C Wijeyewickrema
- Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Ruth M Kennan
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia
| | - Shane B Reeve
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - David L Steer
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Cyril Reboul
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - A Ian Smith
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Robert N Pike
- Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Julian I Rood
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia.
| | - James C Whisstock
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.
| | - Corrine J Porter
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Monash University, Clayton, Victoria 3800, Australia; Departments of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| |
Collapse
|