Fiona M Tomley

Fiona M Tomley
Royal Veterinary College | RVC · Department of Pathobiology and Population Sciences

PhD Manchester 1980

About

278
Publications
60,244
Reads
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7,478
Citations
Citations since 2017
93 Research Items
3401 Citations
20172018201920202021202220230200400600800
20172018201920202021202220230200400600800
20172018201920202021202220230200400600800
20172018201920202021202220230200400600800
Additional affiliations
October 2010 - present
Royal Veterinary College
Position
  • Professor of Experimental Parasitology
October 1993 - October 2010
October 1984 - October 1993
The Pirbright Institute
Position
  • Houghton Poultry Research Station/Institute for Animal Health

Publications

Publications (278)
Article
Full-text available
Irrational and inappropriate use of antibiotics in commercial chicken production can contribute to the development of antimicrobial resistance. We aimed to assess antibiotic usage in commercial chicken production in Bangladesh, and identify factors associated with this practice. We conducted a large-scale cross-sectional study to collect informatio...
Article
Full-text available
The apical complex of apicomplexan parasites is essential for host cell invasion and intracellular survival and as the site of regulated exocytosis from specialised secretory organelles called rhoptries and micronemes. Despite its importance, there are few data on the three-dimensional organisation and quantification of these organelles within the...
Article
Full-text available
Cheap, easy-to-produce oral vaccines are needed for control of coccidiosis in chickens to reduce the impact of this disease on welfare and economic performance. Saccharomyces cerevisiae yeast expressing three Eimeria tenella antigens were developed and delivered as heat-killed, freeze-dried whole yeast oral vaccines to chickens in four separate stu...
Article
Full-text available
Antimicrobial resistance (AMR) is a One Health problem underpinned by complex drivers and behaviours. This is particularly so in low-and middle-income countries (LMICs), where social and systemic factors fuel (mis)use and drive AMR. Behavioural change around antimicrobial use could safeguard both existing and future treatments. However, changing be...
Preprint
Full-text available
The poultry red mite ( Dermanyssus gallinae ), an obligatory blood feeding ectoparasite, is primarily associated with egg laying hens where it is estimated to cause losses of ~€230 million per annum from European farmers. Current control strategies, including the use of acaricidal chemicals and desiccant dusts, are often ineffective and there is wi...
Preprint
Full-text available
Cheap, easy-to-produce oral vaccines are needed for control of coccidiosis in chickens to reduce the impact of this disease on welfare and economic performance. Saccharomyces cerevisiae yeast expressing three Eimeria tenella antigens were developed and delivered as heat-killed, freeze-dried whole yeast oral vaccines to chickens in four separate stu...
Article
Full-text available
Coccidiosis is a potentially severe enteritis caused by species of obligate intracellular parasites of the genus Eimeria. These parasites cause significant economic losses to the poultry industry, predominantly due to compromised efficiency of production as well as the cost of control. These losses were recently estimated to cost chicken producers...
Article
Full-text available
The Coccidia are a subclass of the Apicomplexa and include several genera of protozoan parasites that cause important diseases in humans and animals, with Toxoplasma gondii becoming the ‘model organism’ for research into the coccidian molecular and cellular processes. The amenability to the cultivation of T. gondii tachyzoites and the wide availabi...
Preprint
Full-text available
The apical complex of apicomplexan parasites is essential for host cell invasion and intracellular survival and as the site of regulated exocytosis from specialised secretory organelles called rhoptries and micronemes. Despite its importance, there is little data on the three-dimensional organisation and quantification of these organelles within th...
Article
Full-text available
Coccidiosis caused by Eimeria species parasites remains a major threat to poultry production, undermining economic performance and compromising welfare. The recent characterisation of three new Eimeria species that infect chickens has highlighted that many gaps remain in our knowledge of the biology and epidemiology of these parasites. Concerns abo...
Article
Full-text available
Eimeria maxima is a common cause of coccidiosis in chickens, a disease that has a huge economic impact on poultry production. Knowledge of immunity to E. maxima and the specific mechanisms that contribute to differing levels of resistance observed between chicken breeds and between congenic lines derived from a single breed of chickens is required....
Article
Full-text available
In infections by apicomplexan parasites including Plasmodium, Toxoplasma gondii, and Eimeria, host interactions are mediated by proteins including families of membrane-anchored cysteine-rich surface antigens (SAGs) and SAG-related sequences (SRS). Eimeria tenella causes caecal coccidiosis in chickens and has a SAG family with over 80 members making...
Article
Full-text available
More than 68 billion chickens were produced globally in 2018, emphasising their major contribution to the production of protein for human consumption, and the importance of their pathogens. Protozoan Eimeria spp. are the most economically significant parasites of chickens, incurring global costs of more than UK £10.4 billion per annum. Seven Eimeri...
Article
Full-text available
Following the several episodes of zoonotic disease outbreaks and the more recent COVID-19 pandemic, the Indian policy initiatives are committed to institutionalize One Health (OH) approaches and promote intersectoral, transdisciplinary collaboration and cooperation. The OH principle needs to be visualized beyond the scope of zoonoses. While conserv...
Article
Full-text available
Eimeria species parasites infect the gastrointestinal tract of chickens, causing disease and impacting on production. The poultry industry relies on anticoccidial drugs and live vaccines to control Eimeria and there is a need for novel, scalable alternatives. Understanding the outcomes of experimental infection in commercial chickens is valuable fo...
Article
Full-text available
Ionophore compounds active against Eimeria species are widely used in intensive broiler systems and have formed the backbone of coccidiosis control for almost 50 years. Producers, however, are under pressure to reduce ionophore use due to consumer concerns over antimicrobial usage in food animals, and antimicrobial resistance. Moreover, current vac...
Article
Full-text available
In vitro development of the complete life cycle of Eimeria species has been achieved in primary cultures of avian epithelial cells with low efficiency. The use of immortalized cell lines simplifies procedures but only allows partial development through one round of parasite invasion and intracellular replication. We have assessed the suitability of...
Article
Full-text available
Coccidiosis, caused by Eimeria species parasites, has long been recognised as an economically significant disease of chickens. As the global chicken population continues to grow, and its contribution to food security intensifies, it is increasingly important to assess the impact of diseases that compromise chicken productivity and welfare. In 1999,...
Article
Full-text available
Coccidiosis, caused by Eimeria species parasites, has long been recognised as an economically significant disease of chickens. As the global chicken population continues to grow, and its contribution to food security intensifies, it is increasingly important to assess the impact of diseases that compromise chicken productivity and welfare. In 1999,...
Article
Full-text available
The poultry red mite (Dermanyssus gallinae), an obligatory blood feeding ectoparasite, is primarily associated with laying hens where it is estimated to cause losses of ~€231 million per annum to European farmers. Moderate to high infestation levels result in negative impacts on hen welfare, including increased cannibalism, irritation, feather peck...
Article
Full-text available
Background: Poultry coccidiosis is a parasitic enteric disease with a highly negative impact on chicken production. In-feed chemoprophylaxis remains the primary method of control, but the increasing ineffectiveness of anticoccidial drugs, and potential future restrictions on their use has encouraged the use of commercial live vaccines. Availabilit...
Article
Apicomplexans, including species of Eimeria, pose a real threat to the health and wellbeing of animals and humans. Eimeria parasites do not infect humans but cause an important economic impact on livestock, in particular on the poultry industry. Despite its high prevalence and financial costs, little is known about the cell biology of these 'cosmop...
Preprint
Full-text available
Eimeria maxima is a common cause of coccidiosis in chickens, a disease which has a huge economic impact on poultry production. Knowledge of immunity to E. maxima and the specific mechanisms that contribute to differing levels of resistance observed between chicken breeds and between congenic lines derived from a single breed of chickens is required...
Conference Paper
Full-text available
In recent years, several vaccine candidates have been identified in Dermanyssus gallinae by employing native protein fractionation and testing and/or by selecting antigens by their inferred orthology with protective antigens from other species. Many of the recombinant D. gallinae antigens or native extracts previously tested for vaccine efficacy us...
Article
The advent of metagenomics using Next-Generation Sequencing (NGS) has led to the acquisition of unprecedented quantities of bacterial sequence data. One use for these data is the recovery of complete genomes of uncultivable, and thus uncharacterised, organisms. The separation of genome from metagenomics data remains challenging, however genomes of...
Article
Full-text available
Dermanyssus gallinae, the poultry red mite, is a global threat to the commercial egg-laying industry. Control of D. gallinae is difficult, with only a limited number of effective pesticides and non-chemical treatments available. Here we characterise the candidate vaccine antigen D. gallinae cathepsin D-1 (Dg-CatD-1) and demonstrate that purified re...
Article
Full-text available
Eimeria is a genus of apicomplexan parasites that contains a large number of species, most of which are absolutely host‐specific. Seven species have been recognized to infect chickens. Infection of susceptible chickens results in an intestinal disease called coccidiosis, characterized by mucoid or hemorrhagic enteritis, which is associated with imp...
Article
Eimeria tenella can cause the disease coccidiosis in chickens. The direct and often detrimental impact of this parasite on chicken health, welfare and productivity is well recognised, however less is known about the secondary effects infection may have on other gut pathogens. Campylobacter jejuni is the leading cause of human bacterial food-borne d...
Article
Full-text available
Background Coccidiosis is a major contributor to losses in poultry production. With emerging constraints on the use of in-feed prophylactic anticoccidial drugs and the relatively high costs of effective vaccines, there are commercial incentives to breed chickens with greater resistance to this important production disease. To identify phenotypic bi...
Article
Full-text available
The poultry red mite, Dermanyssus gallinae , is a major worldwide concern in the egg-laying industry. Here, we report the first draft genome assembly and gene prediction of Dermanyssus gallinae , based on combined PacBio and MinION long-read de novo sequencing. The ∼959-Mb genome is predicted to encode 14,608 protein-coding genes.
Article
Full-text available
Coccidiosis in poultry, caused by protozoan parasites of the genus Eimeria, is an intestinal disease with substantial economic impact. With the use of anticoccidial drugs under public and political pressure, and the comparatively higher cost of live-attenuated vaccines, an attractive complementary strategy for control is to breed chickens with incr...
Article
Full-text available
Eimeria species parasites can cause the enteric disease coccidiosis, most notably in chickens where the economic and welfare implications are significant. Seven Eimeria species are recognized to infect chickens, although understanding of their regional occurrence, abundance, and population structure remains limited. Reports of Eimeria circulating i...
Article
Full-text available
Dermanyssus gallinae, the poultry red mite (PRM), is currently the most important ectoparasite of the egg laying industry worldwide with an expanding global prevalence. As a blood feeder, it causes anaemia and severe welfare issues to the hens and is a major cause of economic losses. It is also a vector for Salmonella species, avian influenza and p...
Article
Full-text available
Background The caecal microbiota plays a key role in chicken health and performance, influencing digestion and absorption of nutrients, and contributing to defence against colonisation by invading pathogens. Measures of productivity and resistance to pathogen colonisation are directly influenced by chicken genotype, but host driven variation in mic...
Article
Full-text available
Recently, the availability of protocols supporting genetic complementation of Eimeria has raised the prospect of generating transgenic parasite lines which can function as vaccine vectors, expressing and delivering heterologous proteins. Complementation with sequences encoding immunoprotective antigens from other Eimeria spp. offers an opportunity...
Article
Full-text available
Eimeria spp. are intracellular parasites that have a major impact on poultry. Effective live vaccines are available and the development of reverse genetic technologies has raised the prospect of using Eimeria spp. as recombinant vectors to express additional immunoprotective antigens. To study the ability of Eimeria to secrete foreign antigens or d...
Article
Full-text available
Background: The phylum Apicomplexa comprises a wide variety of parasites of significant medical and economic relevance. These parasites have extremely different host and tissue tropisms; for example Toxoplasma gondii can invade virtually any nucleated cell and infect almost all warm-blooded vertebrates, whereas Eimeria tenella infects only chicken...
Article
Full-text available
Eimeria species parasites can cause the disease coccidiosis, most notably in chickens. The occurrence of coccidiosis is currently controlled through a combination of good husbandry, chemoprophylaxis and/or live parasite vaccination; however, scalable, cost-effective subunit or recombinant vaccines are required. Many antigens have been proposed for...
Article
Full-text available
Eimeria species cause the intestinal disease coccidiosis, most notably in poultry. While the direct impact of coccidiosis on animal health and welfare is clear, its influence on the enteric microbiota and by-stander effects on chicken health and production remains largely unknown, with the possible exception of Clostridium perfringens (necrotic ent...
Data
Summary of sequenced samples. Table outlines infection status (infected or uninfected) and lesion score (LS) group: 0 (no lesions), 1 (mild lesions), 2 (moderate lesions), 3 (severe lesions), 4 (very severe lesions), total number of reads per sample, total number of OTUs* (operational taxonomic units) per sample and the sex of the chicken from whic...
Data
Comparison of alpha diversity indices across uninfected and E. tenella infected groups. Lesion scores (LS) 0 to 4 indicate increasing lesion severity. No statistically significant differences were observed using Kruskal-Wallis tests (P > 0.05). (DOCX)
Data
Differentially abundant OTUs between uninfected samples and lesion score 2 samples. (XLSX)
Data
Differentially abundant OTUs between lesion score 0 and lesion score 4 samples. (XLSX)
Data
Differentially abundant OTUs between lesion score 2 and lesion score 4 samples. (XLSX)
Data
Read length distribution. Histogram of read length, reads ranged from 400 bp to 467 bp, with an average length of 448 bp. (DOCX)
Data
Differentially abundant OTUs between uninfected samples and lesion score 0 samples. (XLSX)
Data
Differentially abundant OTUs between uninfected samples and lesion score 1 samples. (XLSX)
Data
Differentially abundant OTUs between lesion score 0 and lesion score 1–4, symptomatic samples. (XLSX)
Data
Summary of caecal samples collected and sequenced, per group. Samples were grouped by infection status and lesion score, samples were taken forward for Illumina sequencing after Bioanalyzer size verification and quality control. One mock microbial community (HM-782D, Bei resources) was included as a control. (DOCX)