Animal, plant and human health and welfare
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- ItemAllonursing in Wild and Farm Animals: Biological and Physiological Foundations and Explanatory Hypotheses(MDPI, 2021-10-29) Mota-Rojas, Daniel; Marcet-Rius, Míriam; Freitas-de-Melo, Aline; Muns, Ramon; Mora-Medina, Patricia; Domínguez-Oliva, Adriana; Orihuela, AgustínThe dams of gregarious animals must develop a close bond with their newborns to provide them with maternal care, including protection against predators, immunological transference, and nutrition. Even though lactation demands high energy expenditures, behaviors known as allonursing (the nursing of non-descendant infants) and allosuckling (suckling from any female other than the mother) have been reported in various species of wild or domestic, and terrestrial or aquatic animals. These behaviors seem to be elements of a multifactorial strategy, since reports suggest that they depend on the following: species, living conditions, social stability, and kinship relations, among other group factors. Despite their potential benefits, allonursing and allosuckling can place the health and welfare of both non-filial dams and alien offspring at risk, as it augments the probability of pathogen transmission. This review aims to analyze the biological and physiological foundations and bioenergetic costs of these behaviors, analyzing the individual and collective advantages and disadvantages for the dams’ own offspring(s) and alien neonate(s). We also include information on the animal species in which these behaviors occur and their implications on animal welfare.
- ItemAn analysis of effects of heterozygosity in dairy cattle for bovine tuberculosis resistance(Wiley, 2018-01-24) Tsairidou, S.; Allen, Adrian; Pong-Wong, R.; McBride, S.H.; Wright, D.M.; Matika, O.; Pooley, C.M.; McDowell, Stanley W.J.; Glass, E.J.; Skuce, Robin A.; Bishop, S.C.; Woolliams, J.A.Genetic selection of cattle more resistant to bovine tuberculosis (bTB) may offer a complementary control strategy. Hypothesising underlying non-additive genetic variation, we present an approach using genome-wide high density markers to identify genomic loci with dominance effects on bTB resistance and to test previously published regions with heterozygote advantage in bTB. Our data comprised 1151 Holstein–Friesian cows from Northern Ireland, confirmed bTB cases and controls, genotyped with the 700K Illumina BeadChip. Genome-wide markers were tested for associations between heterozygosity and bTB status using marker-based relationships. Results were tested for robustness against genetic structure, and the genotypic frequencies of a significant locus were tested for departures from Hardy-Weinberg equilibrium. Genomic regions identified in our study and in previous publications were tested for dominance effects. Genotypic effects were estimated through ASReml mixed models. A SNP (rs43032684) on chromosome 6 was significant at the chromosome-wide level, explaining 1.7% of the phenotypic variance. In the controls, there were fewer heterozygotes for rs43032684 (P < 0.01) with the genotypic values suggesting that heterozygosity confers a heterozygote disadvantage. The region surrounding rs43032684 had a significant dominance effect (P < 0.01). SNP rs43032684 resides within a pseudogene with a parental gene involved in macrophage response to infection and within a copy-number-variation region previously associated with nematode resistance. No dominance effect was found for the region on chromosome 11, as indicated by a previous candidate region bTB study. These findings require further validation with large-scale data.
- ItemAnti-Campylobacter Probiotics: Latest Mechanistic Insights(Mary Ann Liebert, 2022-07-29) Balta, Igori; Butucel, Eugenia; Stef, Lavinia; Pet, Ioan; Gradisteanu-Pircalabioru, Gratiela; Chifiriuc, Carmen; Gundogdu, Ozan; McCleery, David; Corcionivoschi, NicolaeThe Campylobacter genus is the leading cause of human gastroenteritis, with the consumption of contaminated poultry meat as the main route of infection. Probiotic bacteria, such as Lactobacillus, Bacillus, Escherichia coli Nissle, and Bifidobacterium species, have a great immunomodulatory capacity and exhibit antipathogenic effects through various molecular mechanisms. Reducing Campylobacter levels in livestock animals, such as poultry, will have a substantial benefit to humans as it will reduce disease transmissibility through the food chain. Moreover, probiotic-based strategies might attenuate intestinal inflammatory processes, which consequently reduce the severity of Campylobacter disease progression. At a molecular level, probiotics can also negatively impact on the functionality of various Campylobacter virulence and survival factors (e.g., adhesion, invasion), and on the associated colonization proteins involved in epithelial translocation. The current review describes recent in vitro, in vivo, and preclinical findings on probiotic therapies, aiming to reduce Campylobacter counts in poultry and reduce the pathogen’s virulence in the avian and human host. Moreover, we focused in particular on probiotics with known anti-Campylobacter activity seeking to understand the biological mechanisms involved in their mode of action.
- ItemAntimicrobial Properties of Basidiomycota Macrofungi to Mycobacterium abscessus Isolated from Patients with Cystic Fibrosis(Wolters Kluwer - Medknow, 2019-03-12) Millar, Beverley Cherie; Nelson, David W. V. A.; Moore, Rachel E.; Rao, Juluri R.; Moore, John E.Background: Antimicrobial resistance (AMR) has now emerged as a global public health crisis. Of particular concern is AMR associated with the genus Mycobacterium, including Mycobacterium tuberculosis and the nontuberculous mycobacteria (NTM). Emergence of the NTM, in particular Mycobacterium abscessus, in patients with cystic fibrosis (CF) represents both a diagnostic and a treatment dilemma. Such resistance drives the need to investigate novel sources of antimicrobials. Medicinal fungi have a well‑documented history of use in traditional oriental therapies. Not only is this an ancient practice, but also still today, medical practice in Japan, China, Korea, and other Asian countries continue to rely on fungal‑derived antibiotics. A study was, therefore, undertaken to examine the antimicrobial activity of 23 native macrofungal (mushrooms/ toadstools) taxa, collected from woodlands in Northern Ireland against six clinical (CF) isolates of M. abscessus, as well as M. abscessus National Collection of Type Cultures (NCTC) Reference strain (NCTC 13031). Methods: Free‑growing saprophytic and mycorrhizal macrofungi (n = 23) belonging to the phylum Basidiomycota were collected and were definitively identified employing Polymerase Chain reaction/ITS DNA sequencing. Macrofungal tissues were freeze‑dried and reconstituted before employment in antibiotic susceptibility studies. Results: All macrofungi examined showed varying inhibition of the M. abscessus isolates examined with the exception Russula nigricans. The macrofungi displaying maximum antimycobacterial activity against the clinical isolates were (in descending order) M. giganteus (33.6 mg/ml), Hygrocybe nigrescens (38.5 mg/ml) and Hypholoma fasciculare (25.3 mg/ml). Conclusion: Macrofungi may represent a source of novel antimicrobials against M. abscessus, which have not yet been fully explored nor exploited clinically. This is the first report describing the antimycobacterial properties of extracts of M. giganteus against M. abscessus. Further work is now required to identify the constituents and mode of the inhibitory action of these macrofungi against the M. abscessus. Given the gravity of AMR in the NTMs, particularly M. abscessus and the clinical treatment dilemmas that such AMR present, antibiotic drug discovery efforts should now focus on investigating and developing antibacterial compounds from macrofungi, particularly M. giganteus, where there are no or limited current treatment options.
- ItemAntimicrobial resistance (AMR): significance to food quality and safety(Oxford University Press, 2019-04-09) Nelson, David W. V. A.; Moore, John E.; Rao, Juluri R.Antibiotic resistance presents a significant challenge to clinical, veterinary, and plant health and is now recognized by the World Health Organization (WHO) as a major emerging problem of global significance. As yet, there have been no successful discoveries of classes of novel antibiotics since 1987. There is an antibiotic discovery void, and it is now widely acknowledged that there is an urgent need for the development of novel antimicrobial agents. For economic reasons, many of the largest pharmaceutical companies have abandoned the antibiotic field, and research conducted by academia was scaled back due to funding cuts following the economic crisis. A post-antibiotic era— in which common infections and minor injuries can kill—far from being an apocalyptic fantasy, is indeed a very real possibility for the 21st century.
- ItemThe Antioxidant Effect of Natural Antimicrobials in Shrimp Primary Intestinal Cells Infected with Nematopsis messor(MDPI, 2022-05-15) Balta, Igori; Stef, Lavinia; Butucel, Eugenia; Pircalabioru, Gratiela Gradisteanu; Venig, Adelina; Ward, Patrick; Deshaies, Myriam; Pet, Ioan; Stef, Ducu; Koyun, Osman Y.; Callaway, Todd R.; Gundogdu, Ozan; Corcionivoschi, NicolaeNematopsis messor infections severely impact on shrimp’s health with devastating economic consequences on shrimp farming. In a shrimp primary intestinal cells (SGP) model of infection, a sub-inhibitory concentration (0.5%) of natural antimicrobials (Aq) was able to reduce the ability of N. messor to infect (p < 0.0001). To prevent N. messor infection of SGP cells, Aq inhibits host actin polymerization and restores tight junction integrity (TEER) and the expression of Zo-1 and occluding. The oxidative burst, caused by N. messor infection, is attenuated by Aq through the inhibition of NADPH-produced H2O2. Simultaneous to the reduction in H2O2 released, the activity of catalase (CAT) and superoxide dismutase (SOD) were also significantly increase (p < 0.0001). The antimicrobial mixture inactivates the ERK signal transduction pathway by tyrosine dephosphorylation and reduces the expression of DCR2, ALF-A, and ALF-C antimicrobial peptides. The observed in vitro results were also translated in vivo, whereby the use of a shrimp challenge test, we show that in N. messor infected shrimp the mortality rate was 68% compared to the Aq-treated group where the mortality rate was maintained at 14%. The significant increase in CAT and SOD activity in treated and infected shrimp suggested an in vivo antioxidant role for Aq. In conclusion, our study shows that Aq can efficiently reduce N. messor colonization of shrimp’s intestinal cells in vitro and in vivo and the oxidative induced cellular damage, repairs epithelial integrity, and enhances gut immunity
- ItemAssessing the impact of participatory extension programme membership on farm business performance in Northern Ireland.(MDPI, 2021-09-30) Adenuga, Adewale; Jack, Claire G.; Ashfield, Austen; Wallace, MichaelThis paper evaluates the impact of membership of the Business Development Groups (BDG), a participatory extension programme in Northern Ireland on the economic performance of participating farmers for dairy and sheep enterprise groups. The study employs the conditional difference-in-differences approach which combines a non-parametric matching estimator with a difference-in-differences analytical technique to obtain a credible best-estimates of the causal effect of BDG membership on farmers’ economic performance assuming that BDG participation is as good as random after controlling for observable farm characteristics and that the parallel trends assumption holds between BDG participants and non-participants. The results of the analyses showed that membership in the BDG programme has a statistically significant impact on the economic performance of participating farmers. Specifically, the results showed that farmers who are members of the dairy and sheep BDGs increased their gross margin by £109.10 and £17.10 per head respectively compared to farmers that are non-members of the BDGs. The results of the study provide robust evidence to inform policy development around the area of participatory extension programmes. It also supports the design of efficient agricultural education and extension systems that incorporates the ideas of the farmers themselves through peer-to-peer learning thereby maximising the economic and social benefits accruable from such programmes.
- ItemAssessment and Validation of Globodera pallida as a Novel In Vivo Model for Studying Alzheimer’s Disease(MDPI, 2021-09-19) Althobaiti, Norah A.; Menaa, Farid; Albalawi, Aishah E.; Dalzell, Johnathan; Warnock, Neil; McCammick, Erin M.; Alsolais, Abdulellah; Alkhaibari, Abeer M.; Green, Brian D.Background: Whole transgenic or non-transgenic organism model systems allow the screening of pharmacological compounds for protective actions in Alzheimer’s disease (AD). Aim: In this study, a plant parasitic nematode, Globodera pallida, which assimilates intact peptides from the external environment, was investigated as a new potential non-transgenic model system of AD. Methods: Fresh second-stage juveniles of G. pallida were used to measure their chemosensory, perform immunocytochemistry on their neurological structures, evaluate their survival rate, measure reactive oxygen species, and determine total oxidized glutathione to reduced glutathione ratio (GSSG/GSH) levels, before and after treatment with 100 µM of various amyloid beta (Aβ) peptides (1–40, 1–42, 17–42, 17–40, 1–28, or 1–16). Wild-type N2 C. elegans (strain N2) was cultured on Nematode Growth Medium and directly used, as control, for chemosensory assays. Results: We demonstrated that: (i) G. pallida (unlike Caenorhabditis elegans) assimilates amyloid-β (Aβ) peptides which co-localise with its neurological structures; (ii) pre-treatment with various Aβ isoforms (1–40, 1–42, 17–42, 17–40, 1–28, or 1–16) impairs G. pallida’s chemotaxis to differing extents; (iii) Aβ peptides reduced survival, increased the production of ROS, and increased GSSG/GSH levels in this model; (iv) this unique model can distinguish differences between different treatment concentrations, durations, and modalities, displaying good sensitivity; (v) clinically approved neuroprotective agents were effective in protecting G. pallida from Aβ (1–42) exposure. Taken together, the data indicate that G. pallida is an interesting in vivo model with strong potential for discovery of novel bioactive compounds with anti-AD activity.
- ItemAssessment of Rapid MinION Nanopore DNA Virus Meta-Genomics Using Calves Experimentally Infected with Bovine Herpes Virus-1(MDPI, 2022-08-24) Esnault, Gaelle; Earley, Bernadette; Cormican, Paul; Waters, Sinead M.; Lemon, Ken; Cosby, S. Louise; Lagan, Paula; Barry, Thomas; Reddington, Kate; McCabe, Matthew S.Bovine respiratory disease (BRD), which is the leading cause of morbidity and mortality in cattle, is caused by numerous known and unknown viruses and is responsible for the widespread use of broad-spectrum antibiotics despite the use of polymicrobial BRD vaccines. Viral metagenomics sequencing on the portable, inexpensive Oxford Nanopore Technologies MinION sequencer and sequence analysis with its associated user-friendly point-and-click Epi2ME cloud-based pathogen identification software has the potential for point-of-care/same-day/sample-to-result metagenomic sequence diagnostics of known and unknown BRD pathogens to inform a rapid response and vaccine design. We assessed this potential using in vitro viral cell cultures and nasal swabs taken from calves that were experimentally challenged with a single known BRD-associated DNA virus, namely, bovine herpes virus 1. Extensive optimisation of the standard Oxford Nanopore library preparation protocols, particularly a reduction in the PCR bias of library amplification, was required before BoHV-1 could be identified as the main virus in the in vitro cell cultures and nasal swab samples within approximately 7 h from sample to result. In addition, we observed incorrect assignment of the bovine sequence to bacterial and viral taxa due to the presence of poor-quality bacterial and viral genome assemblies in the RefSeq database used by the EpiME Fastq WIMP pathogen identification software.
- ItemAssociations between Circulating IGF-1 Concentrations, Disease Status and the Leukocyte Transcriptome in Early Lactation Dairy Cows(MDPI, 2021-11-25) Wathes, D. Claire; Becker, Frank; Buggiotti, Laura; Crowe, Mark A.; Ferris, Conrad; Foldager, Leslie; Grelet, Clément; Hostens, Miel; Ingvartsen, Klaus L.; Marchitelli, Cinzia; Salavati, Mazdak; Signorelli, Federica; Takeda, Haruko; Tang, Lijing; Cheng, Zhangrui; GplusE ConsortiumPeripartum dairy cows commonly experience negative energy balance (EB) and immunosuppression together with high incidences of infectious and metabolic disease. This study investigated mechanisms linking EB status with immune defense in early lactation. Data were collected from multiparous Holstein cows from six herds and leukocyte transcriptomes were analyzed using RNA sequencing. Global gene expression was related to circulating IGF-1 (as a biomarker for EB) by subdividing animals into three groups, defined as IGF-1 LOW (<35 ng/mL, n = 35), MODERATE (35–100 ng/mL, n = 92) or HIGH (>100 ng/mL, n = 43) at 14 ± 4 days in milk (DIM). Differentially expressed genes between groups were identified using CLC Genomics Workbench V21, followed by cluster and KEGG pathway analysis, focusing on the comparison between LOW and HIGH IGF-1 cows. LOW cows were older and had significantly lower dry matter intakes and EB values, whereas HIGH cows produced more milk. During the first 35 DIM, 63% of LOW cows had more than one health problem vs. 26% HIGH cows, including more with clinical mastitis and uterine infections. Gene expression analysis indicated that leukocytes in LOW cows switched energy metabolism from oxidative phosphorylation to aerobic glycolysis (PGM, LDH, and PDK4). Many antimicrobial peptides were up-regulated in LOW cows (e.g., PTX3, DMBT1, S100A8, and S100A9) together with genes associated with inflammation, platelet activation and the complement cascade. HIGH cows had greater expression of genes regulating T and B cell function and the cytoskeleton. Overall, results suggested an ongoing cycle of poor EB and higher infection rates in LOW IGF-1 cows which was reflected in altered leukocyte functionality and reduced milk production.
- ItemATAC-Seq identifies regions of open chromatin in the bronchial lymph nodes of dairy calves experimentally challenged with bovine respiratory syncytial virus(BMC (Springer nature), 2021-01-06) Johnston, Dayle; JaeWoo, Kim; Taylor, Jeremy F.; Earley, Bernadette; McCabe, Matthew S.; Lemon, Ken; Duffy, Catherine; McMenamy, Michael; Cosby, S. Louise; Waters, Sinéad M.Background: Bovine Respiratory Syncytial Virus (BRSV) is a cause of Bovine Respiratory Disease (BRD). DNA-based biomarkers contributing to BRD resistance are potentially present in non-protein-coding regulatory regions of the genome, which can be determined using ATAC-Seq. The objectives of this study were to: (i) identify regions of open chromatin in DNA extracted from bronchial lymph nodes (BLN) of healthy dairy calves experimentally challenged with BRSV and compare them with those from non-challenged healthy control calves, (ii) elucidate the chromatin regions that were differentially or uniquely open in the BRSV challenged relative to control calves, and (iii) compare the genes found in regions proximal to the differentially open regions to the genes previously found to be differentially expressed in the BLN in response to BRSV and to previously identified BRD susceptibility loci. This was achieved by challenging clinically healthy Holstein-Friesian calves (mean age 143 ± 14 days) with either BRSV inoculum (n = 12) or with sterile phosphate buffered saline (PBS) (n = 6) and preparing and sequencing ATACSeq libraries from fresh BLN tissues. Results: Using Diffbind, 9,144 and 5,096 differentially accessible regions (P < 0.05, FDR < 0.05) were identified between BRSV challenged and control calves employing DeSeq2 and EdgeR, respectively. Additionally, 8,791 chromatin regions were found to be uniquely open in BRSV challenged calves. Seventy-six and 150 of the genes that were previously found to be differentially expressed using RNA-Seq, were located within 2 kb downstream of the differentially accessible regions, and of the regions uniquely open in BRSV challenged calves, respectively. Pathway analyses within ClusterProfiler indicated that these genes were involved in immune responses to infection and participated in the Th1 and Th2 pathways, pathogen recognition and the anti-viral response. There were 237 differentially accessible regions positioned within 40 previously identified BRD susceptibility loci. Conclusions: The identified open chromatin regions are likely to be involved in the regulatory response of gene transcription induced by infection with BRSV. Consequently, they may contain variants which impact resistance to BRD that could be used in breeding programmes to select healthier, more robust cattle.
- ItemBadger territoriality maintained despite disturbance of major road construction(PLOS ( Public Library of Science), 2021-09-03) Gaughran, Aoibheann; Mullen, Enda; MacWhite, Teresa; Maher, Peter; Kelly, David J.; Kelly, Ruth; Good, Margaret; Marples, Nicola M.Road ecology has traditionally focused on the impact of in-situ and functional roads on wildlife. However, road construction also poses a major, yet understudied, threat and the implications for key aspects of animal behaviour are unknown. Badgers (Meles meles) have been implicated in the transmission of tuberculosis to cattle. There are concerns that environmental disturbances, including major road construction, can disrupt badger territoriality, promoting the spread of the disease to cattle. To address these knowledge gaps the ranging behaviour of a medium-density Irish badger population was monitored using GPS-tracking collars before, during, and after a major road realignment project that bisected the study area. We estimated badgers’ home range sizes, nightly distances travelled, and the distance and frequency of extra-territorial excursions during each phase of the study and quantified any changes to these parameters. We show that road construction had a very limited effect on ranging behaviour. A small increase in nightly distance during road construction did not translate into an increase in home range size, nor an increase in the distance or frequency of extra-territorial excursions during road construction. In addition, suitable mitigation measures to prevent badger deaths appeared to ensure that normal patterns of ranging behaviour continued once the new road was in place. We recommend that continuous badger- proof fencing be placed along the entire length of new major roads, in combination with appropriately sited underpasses. Our analysis supports the view that road construction did not cause badgers to change their ranging behaviour in ways likely to increase the spread of tuberculosis.
- ItemA Bayesian analysis of a Test and Vaccinate or Remove study to control bovine tuberculosis in badgers (Meles meles)(Public Library of Science (PLoS), 2021-01-28) Arnold, Mark E.; Courcier, Emily A.; Stringer, Lesley A.; McCormick, Carl M.; Pascual-Linaza, Ana V.; Collins, Shane F.; Trimble, Nigel A.; Ford, Tom; Thompson, Suzan; Corbett, David; Menzies, Frazer D.A novel five year Test and Vaccinate or Remove (TVR) wildlife research intervention project in badgers (Meles meles) commenced in 2014 in a 100km2 area of Northern Ireland. It aimed to increase the evidence base around badgers and bovine TB and help create well-informed and evidence-based strategies to address the issue of cattle-to-cattle spread and spread between cattle and badgers. It involved real-time trap-side testing of captured badgers and vaccinating those that tested negative for bTB (BadgerBCG–BCG Danish 1331) and removal of those that tested bTB positive using the Dual-Path Platform VetTB test (DPP) for cervids (Chembio Diagnostic Systems, Medford, NY USA). Four diagnostic tests were utilised within the study interferon gamma release assay (IGRA), culture (clinical samples and post mortem), DPP using both whole blood and DPP using serum. BCG Sofia (SL222) was used in the final two years because of supply issues with BadgerBCG. Objectives for this study were to evaluate the performance of the DPP in field conditions and whether any trend was apparent in infection prevalence over the study period. A Bayesian latent class model of diagnostic test evaluation in the absence of a gold standard was applied to the data. Temporal variation in the sensitivity of DPP and interferon gamma release assay (IGRA) due to the impact of control measures was investigated using logistic regression and individual variability was assessed. Bayesian latent class analysis estimated DPP with serum to have a sensitivity of 0.58 (95% CrI: 0.40–0.76) and specificity of 0.97 (95% CrI: 0.95–0.98). The DPP with whole blood showed a higher sensitivity (0.69 (95% CrI: 0.48–0.88)) but similar specificity (0.98 (95% Crl: 0.96–0.99)). The change from BCG Danish to BCG Sofia significantly impacted on DPP serum test characteristics. In addition, there was weak evidence of increasing sensitivity of IGRA over time and differences in DPP test sensitivity between adults and cubs. An exponential decline model was an appropriate representation of the infection prevalence over the 5 years, with a starting prevalence of 14% (95% CrI: 0.10–0.20), and an annual reduction of 39.1% (95% CrI: 26.5–50.9). The resulting estimate of infection prevalence in year 5 of the study was 1.9% (95% CrI: 0.8–3.8). These results provide field evidence of a statistically significant reduction in badger TB prevalence supporting a TVR approach to badger intervention. They give confidence in the reliability and reproducibility in the DPP Whole Blood as a real time trap-side diagnostic test for badgers, and describe the effect of vaccination and reduced infection prevalence on test characteristics.
- ItemBayesian latent class estimation of sensitivity and specificity parameters of diagnostic tests for bovine tuberculosis in chronically infected herds in Northern Ireland(Elsevier, 2018-05-01) Lahuerta-Marin, Angela; Milne, Georgina; McNair, James; Skuce, Robin; McBride, S.H.; Menzies, F.D.; McDowell, Stanley; Byrne, A.W.; Handel, I.G.; Bronsvoort, B.M. de C.In the European Union, the recommended ante-mortem diagnostic methods for bovine tuberculosis (bTB) include the single intradermal cervical comparative tuberculin (SICCT) test and the interferon-gamma (IFN- g) test as an ancillary test. The SICCT test has a moderate sensitivity (Se) and high specificity (Sp), while the IFN-g test has good Se, but a lower Sp than the SICCT test. A retrospective Bayesian latent class analysis was conducted on 71,185 cattle from 806 herds chronically infected with bTB distributed across Northern Ireland (NI) to estimate the Se and Sp of the common ante-mortem tests and meat inspection. Analyses were also performed on data stratified by farming type and herd location to explore possible differences in test performance given the heterogeneity in the population. The mean estimates in chronically infected herds were: (1) ‘standard’ SICCT: Se 40.5–57.7%, Sp 96.3–99.7%; (2) ‘severe’ SICCT: Se 49.0%–60.6%, Sp 94.4–99.4%; (3) IFN-g(bovine–avian) using a NI optical density (OD) cut-off difference of 0.05: IFN-g(B–A)NI: Se 85.8– 93.0%, Sp 75.6–96.2%; (4) IFN-g(bovine–avian) using a standard ‘commercial’ OD cut-off difference of 0.1: IFN-g(B–A)0.1: Se 83.1–92.1%, Sp 83.1–97.3%; and (5) meat inspection: Se 49.0–57.1% Se, Sp 99.1–100%. Se estimates were lower in cattle from dairy farms than from beef farms. There were no notable differences in estimates by location of herds. Certain population characteristics, such as production type, might influence the ability of bTB tests to disclose truly infected cases.
- ItemBio-Fabrication of Human Amniotic Membrane Zinc Oxide Nanoparticles and the Wet/Dry HAM Dressing Membrane for Wound Healing(Frontiers Media, 2021-07-28) Ramasamy, Palaniappan; Krishnakumar, Ramachandran; Rekha, Ravichandran; Vaseeharan, Baskaralingam; Saraswathi, K.; Raj, Mohan; Hanna, Robert E.B.; Brennan, Gerard P.; Dayanithi, Govindan; Vijayakumar, SekarThe preparation of unique wet and dry wound dressing products derived from unprocessed human amniotic membrane (UP-HAM) is described. The UP-HAM was decellularized, and the constituent proteins were cross-linked and stabilized before being trimmed and packed in sterile Nucril-coated laminated aluminium foil pouches with isopropyl alcohol to manufacture processed wet human amniotic membrane (PWHAM). The dry type of PD-HAM was prepared by decellularizing the membrane, UV irradiating it, lyophilizing/freeze-drying it, sterilizing it, and storing it at room temperature. The UP-HAM consists of a translucent yellowish mass of flexible membranes with an average thickness of 42 µm. PW-HAM wound dressings that had been processed, decellularized, and dehydrated had a thinner average thickness of 30 µm and lacked nuclear-cellular structures. Following successful decellularization, discrete bundle of fibrous components in the stromal spongy layers, microvilli and reticular ridges were still evident on the surface of the processed HAM, possibly representing the location of the cells that had been removed by the decellularization process. Both wet and dry HAM wound dressings are durable, portable, have a shelf life of 3–5 years, and are available all year. A slice of HAM dressing costs 1.0 US$/cm2 . Automation and large-scale HAM membrane preparation, as well as storage and transportation of the dressings, can all help to establish advanced technologies, improve the efficiency of membrane production, and reduce costs. Successful treatment of wounds to the cornea of the eye was achieved with the application of the HAM wound dressings. The HAM protein analysis revealed 360 µg proteins per gram of tissue, divided into three main fractions with MWs of 100 kDa, 70 kDa, and 14 kDa, as well as seven minor proteins, with the 14 kDa protein displaying antibacterial properties against human pathogenic bacteria. Frontiers in Bioengineering and Biotechnology | www.frontiersin.org 1 July 2021 | Volume 9 | Article 695710 fbioe-09-695710 July 22, 2021 Time: 16:39 # 2 Ramasamy et al. HAMP-ZnO Nanoparticles HAM Wound Dressing Wet and dry wound dressings were produced. HAM proteins were purified and analysed. The zinc oxide nanoparticles (HAMP-ZnO NP) made from HAM proteins were characterised and tested for their antibacterial activity. Wounds to the cornea of the eye healed easily when treated with HAM wound dressings. Fresh human Amniotic membrane, Serological screening, selection of disease-free HAM, reome stromal layer, preparation of HAM. UNPROCESSED HAM Cuboidal epithelial cells, basement membrane, compact layer, stromal and spongy layers containing scatted fibroblast cells are visible in hsitological analysis. The flow chart depicts the methods for processing, and preparation of wet (PWHAM) and dry (PD-HAM) wound healing dressings. HAM proteins, Nanoparticle synthesis (HAMP-ZnO NP) and analysis. Antibacterial analysis show Inhibition of growth and biofilm formation of pathogenic bacteria . Processed HAM lacked a nuclear-cellular epithelium, but it did have a distinct fibrous elements in basement membrane, stromal and spongy layers. Processed PW-HAM (Light &SEM) showed smooth epithelial surface topography with microvilli,. HAM dressing, wet/dry, packed, labelled, sterilised and processed. They are durable, portable, have long shelf life . A slice of HAM dressing costs US$ 1.0 / cm² . The wound dressings are ready to be applied. The dermal wounds and conjunctival surface can be successfully repaired using processed HAM wound dressings GRAPHICAL ABSTRACT | Flow chart depicting the methods, preparing, and characterizing, by histological, and scanning electron microscopy, of wet (PW-HAM) and dry (PD-HAM)of wound healing dressing, and preparation of nanoparticles (HAMP ZnO NP); and application of HAM wound dressing. A wide range of antibacterial activity was observed after treatment with 75 µg/ml zinc oxide nanoparticles derived from human amniotic membrane proteins (HAMP-ZnO NP), including dose-dependent biofilm inhibition and inhibition of Gram-positive (S. aureus, S. mutans, E. faecalis, and L. fusiformis) and Gram-negative bacteria (S. sonnei, P. aeruginosa, P. vulgaris, and C. freundii).
- ItemBiocides as Biomedicines against Foodborne Pathogenic Bacteria(MDPI, 2022-02-04) Butucel, Eugenia; Balta, Igori; Ahmadi, Mirela; Dumitrescu, Gabi; Morariu, Florica; Pet, Ioan; Stef, Lavinia; Corcionivoschi, NicolaeBiocides are currently considered the first line of defense against foodborne pathogens in hospitals or food processing facilities due to the versatility and efficiency of their chemical active ingredients. Understanding the biological mechanisms responsible for their increased efficiency, especially when used against foodborne pathogens on contaminated surfaces and materials, represents an essential first step in the implementation of efficient strategies for disinfection as choosing an unsuitable product can lead to antibiocide resistance or antibiotic–biocide cross-resistance. This review describes these biological mechanisms for the most common foodborne pathogens and focuses mainly on the antipathogen effect, highlighting the latest developments based on in vitro and in vivo studies. We focus on biocides with inhibitory effects against foodborne bacteria (e.g., Escherichia spp., Klebsiella spp., Staphylococcus spp., Listeria spp., Campylobacter spp.), aiming to understand their biological mechanisms of action by looking at the most recent scientific evidence in the field.
- ItemBioinformatic Analysis of the Campylobacter jejuni Type VI Secretion System and Effector Prediction(Frontiers Media, 2021-06-29) Robinson, Luca; Liaw, Janie; Omole, Zahra; Xia, Dong; van Vliet, Arnoud H.M.; Corcionivoschi, Nicolae; Hachani, Abderrahman; Gundogdu, OzanThe Type VI Secretion System (T6SS) has important roles relating to bacterial antagonism, subversion of host cells, and niche colonisation. Campylobacter jejuni is one of the leading bacterial causes of human gastroenteritis worldwide and is a commensal coloniser of birds. Although recently discovered, the T6SS biological functions and identities of its effectors are still poorly defined in C. jejuni. Here, we perform a comprehensive bioinformatic analysis of the C. jejuni T6SS by investigating the prevalence and genetic architecture of the T6SS in 513 publicly available genomes using C. jejuni 488 strain as reference. A unique and conserved T6SS cluster associated with the Campylobacter jejuni Integrated Element 3 (CJIE3) was identified in the genomes of 117 strains. Analyses of the T6SS-positive 488 strain against the T6SS-negative C. jejuni RM1221 strain and the T6SS-positive plasmid pCJDM202 carried by C. jejuni WP2-202 strain defined the “T6SS-containing CJIE3” as a pathogenicity island, thus renamed as Campylobacter jejuni Pathogenicity Island-1 (CJPI-1). Analysis of CJPI-1 revealed two canonical VgrG homologues, CJ488_0978 and CJ488_0998, harbouring distinct C-termini in a genetically variable region downstream of the T6SS operon. CJPI-1 was also found to carry a putative DinJ-YafQ Type II toxin-antitoxin (TA) module, conserved across pCJDM202 and the genomic island CJIE3, as well as several open reading frames functionally predicted to encode for nucleases, lipases, and peptidoglycan hydrolases. This comprehensive in silico study provides a framework for experimental characterisation of T6SS-related effectors and TA modules in C. jejuni
- ItemBovine Tuberculosis in Britain and Ireland – A Perfect Storm? the Confluence of Potential Ecological and Epidemiological Impediments to Controlling a Chronic Infectious Disease(Frontiers Media, 2018-06-05) Allen, Adrian; Skuce, Robin A.; Byrne, A.W.Successful eradication schemes for bovine tuberculosis (bTB) have been implemented in a number of European and other countries over the last 50 years. However, the islands of Britain and Ireland remain a significant aberration to this trend, with the recent exception of Scotland. Why have eradication schemes failed within these countries, while apparently similar programs have been successful elsewhere? While significant socioeconomic and political factors have been discussed elsewhere as key determinants of disease eradication, here we review some of the potential ecological and epidemiological constraints that are present in these islands relative to other parts of Europe. We argue that the convergence of these potential factors may interact additively to diminish the potential of the present control programs to achieve eradication. Issues identified include heterogeneity of diagnostic testing approaches, the presence of an abundant wildlife reservoir of infection and the challenge of sustainably managing this risk effectively; the nature, size, density and network structure of cattle farming; potential effects of Mycobacterium bovis strain heterogeneity on disease transmission dynamics; possible impacts of concurrent endemic infections on the disclosure of truly infected animals; climatological differences and change coupled with environmental contamination. We further argue that control and eradication of this complex disease may benefit from an ecosystem level approach to management. We hope that this perspective can stimulate a new conversation about the many factors potentially impacting bTB eradication schemes in Britain and Ireland and possibly stimulate new research in the areas identified.
- ItemBovine tuberculosis visible lesions in cattle culled during herd breakdowns: the effects of individual characteristics, trade movement and co-infection(Springer, 2017-12) Byrne, Andrew W.; Graham, Jordon; Brown, Craig; Donaghy, Aoibheann; Guelbenzu Gonzalo, Maria; McNair, James; Skuce, Robin A.; Allen, Adrian; McDowell, Stanley W.J.Background: Bovine tuberculosis (bTB), caused by Mycobacterium bovis, remains a significant problem for livestock industries in many countries worldwide including Northern Ireland, where a test and slaughter regime has utilised the Single Intradermal Comparative Cervical Tuberculin (SICCT) test since 1959. We investigated the variation in post-mortem confirmation based on bTB visible lesion (VL) presence during herd breakdowns using two model suites. We investigated animal-level characteristics, while controlling for herd-level factors and clustering. We were interested in potential impacts of concurrent infection, and therefore we assessed whether animals with evidence of liver fluke infection (Fasciola hepatica; post-mortem inspection), M. avium reactors (animals with negative M. bovis-avium (b-a) tuberculin reactions) or Bovine Viral Diarrhoea Virus (BVDV; RT-PCR tested) were associated with bTB confirmation. Results: The dataset included 6242 animals removed during the 14 month study period (2013–2015). bTB-VL presence was significantly increased in animals with greater b-a reaction size at the disclosing SICCT test (e.g. b-a = 5- 9 mm vs. b-a = 0 mm, adjusted Odds ratio (aOR): 14.57; p < 0.001). M. avium reactor animals (b-a < 0) were also significantly more likely to disclose VL than non-reactor animals (b-a = 0; aOR: 2.29; p = 0.023). Animals had a greater probability of exhibiting lesions with the increasing number of herds it had resided within (movement; logherds: aOR: 2.27–2.42; p < 0.001), if it had an inconclusive penultimate test result (aOR: 2.84–3.89; p < 0.001), and with increasing time between tests (log-time; aOR: 1.23; p = 0.003). Animals were less likely to have VL if they were a dairy breed (aOR: 0.79; p = 0.015) or in an older age-class (e.g. age-quartile 2 vs. 4; aOR: 0.65; p < 0.001). Liver fluke or BVDV variables were not retained in either multivariable model as they were non-significantly associated with bTB-VL status (p > 0.1). Conclusions: Our results suggest that neither co-infection of liver fluke nor BVDV had a significant effect on the presence of VLs in this high-risk cohort. M. avium tuberculin reactors had a significantly increased risk of disclosing with a bTB lesion, which could be related to the impact of co-infection with M. avium subsp. paratuberculosis (MAP) affecting the performance of the SICCT however further research in this area is required. Movements, test history, breed and age were important factors influencing confirmation in high-risk animals.
- ItemCan We Breed Cattle for Lower Bovine TB Infectivity?(Frontiers Media, 2018-12-07) Tsairidou, Smaragda; Allen, Adrian; Banos, Georgios; Coffey, Mike; Anacleto, Osvaldo; Byrne, Andrew W.; Skuce, Robin; Glass, Elizabeth J.; Woolliams, John A.; Doeschl-Wilson, Andrea B.Host resistance and infectivity are genetic traits affecting infectious disease transmission. This Perspective discusses the potential exploitation of genetic variation in cattle infectivity, in addition to resistance, to reduce the risk, and prevalence of bovine tuberculosis (bTB). In bTB, variability in M. bovis shedding has been previously reported in cattle and wildlife hosts (badgers and wild boars), but the observed differences were attributed to dose and route of infection, rather than host genetics. This article addresses the extent to which cattle infectivity may play a role in bTB transmission, and discusses the feasibility, and potential benefits from incorporating infectivity into breeding programmes. The underlying hypothesis is that bTB infectivity, like resistance, is partly controlled by genetics. Identifying and reducing the number of cattle with high genetic infectivity, could reduce further a major risk factor for herds exposed to bTB. We outline evidence in support of this hypothesis and describe methodologies for detecting and estimating genetic parameters for infectivity. Using genetic-epidemiological predictionmodels we discuss the potential benefits of selection for reduced infectivity and increased resistance in terms of practical field measures of epidemic risk and severity. Simulations predict that adding infectivity to the breeding programme could enhance and accelerate the reduction in breakdown risk compared to selection on resistance alone. Therefore, given the recent launch of genetic evaluations for bTB resistance and the UK government’s goal to eradicate bTB, it is timely to consider the potential of integrating infectivity into breeding schemes.