Theo de Waal

ORCID: 0000-0002-9657-1857
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About
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Research Areas
  • Helminth infection and control
  • Vector-borne infectious diseases
  • Vector-Borne Animal Diseases
  • Parasite Biology and Host Interactions
  • Parasitic Infections and Diagnostics
  • Viral Infections and Vectors
  • Coccidia and coccidiosis research
  • Parasites and Host Interactions
  • Toxin Mechanisms and Immunotoxins
  • Animal Behavior and Welfare Studies
  • Plant and fungal interactions
  • Insect Pest Control Strategies
  • Toxoplasma gondii Research Studies
  • Mollusks and Parasites Studies
  • Nematode management and characterization studies
  • Amoebic Infections and Treatments
  • Microbial infections and disease research
  • Research on Leishmaniasis Studies
  • Agricultural pest management studies
  • Trypanosoma species research and implications
  • Insect and Pesticide Research
  • Milk Quality and Mastitis in Dairy Cows
  • Genetic and phenotypic traits in livestock
  • Animal Disease Management and Epidemiology
  • Plant Parasitism and Resistance

University College Dublin
2016-2025

Département Santé Animale
2018

University of Amsterdam
2016

Agriculture and Food
2010

Onderstepoort Veterinary Institute
1995-2004

SUMMARY Small subunit ribosomal RNA (srRNA) genes of three Theileria species, one Cytauxzoon and four Babesia species were amplified using the polymerase chain reaction (PCR), cloned sequenced. Our sequences aligned with srRNA previously published for eight Apicomplexa, ciliate dinoflagellate, last two being included as free-living outgroup species. Phylogenetic relationships between organisms inferred by in-dependent methods phylogenetic tree construction Oxytricha nova to root trees. trees...

10.1017/s0031182000068232 article EN Parasitology 1994-02-01

Infections with parasitic helminths (nematodes and trematodes) represent a significant economic welfare burden to the global ruminant livestock industry. The increasing prevalence of anthelmintic resistance means that current control programmes are costly unsustainable in long term. Recent changes epidemiology, seasonality geographic distribution helminth infections have been attributed climate change. However, other environment (e.g., land use) farming, such as intensification altered...

10.3390/agriculture3030484 article EN cc-by Agriculture 2013-08-26

Abstract Blood samples were obtained from 38 wild red deer ( Cervus elaphus ) at two sites in Ireland and subjected to PCR analysis of the 18S rRNA gene followed by sequencing. Two fragments generated different protocols subsequent sequencing suggested that least six infected a babesia that, those loci, is indistinguishable Babesia divergens , an important tick-borne pathogen cattle zoonotic significance. Additionally, B. odocoilei -like parasite was detected three did not match any...

10.1186/1297-9716-42-7 article EN cc-by Veterinary Research 2011-01-18

Resistance to benzimidazoles (BZs) in trichostrongyloid nematodes is a worldwide problem for livestock production, particularly regarding small ruminants. Sensitive and reliable methods are required assess anthelmintic resistance status. Currently available BZ detection can be divided into three main groups, vivo (e.g. faecal egg count reduction test), vitro hatch assay) molecular tests. Three single nucleotide polymorphisms (SNPs) the isotype-1 β-tubulin gene of various nematode species...

10.1016/j.ijpddr.2016.10.002 article EN cc-by-nc-nd International Journal for Parasitology Drugs and Drug Resistance 2016-10-11

Gastrointestinal helminths are ubiquitous in horse populations across the world. Intensive anthelmintic treatments have succeeded controlling some of pathogenic effects these parasites. However, success drugs has been threatened by development widespread resistance to those most commonly used. To develop improved control strategies, information on helminth distribution patterns is needed, which can be obtained identifying animals regarded as high egg shedders and taking age, gender, other...

10.3390/ani13040581 article EN cc-by Animals 2023-02-07

Cryptosporidium is an important cause of diarrhoeal disease worldwide and, as several recent waterborne outbreaks have shown, poses a significant threat to public health in Ireland. We identified the spp. 199 positive human stool samples by PCR-RFLP 18S rRNA and COWP gene loci. Subspecies were 104 sequence analysis 60 kDa glycoprotein (gp60) fragment. Overall C. parvum was 80%, hominis 20% cases. No other detected. far most common species rural, more sparsely populated west Ireland exhibited...

10.1017/s0950268808000769 article EN Epidemiology and Infection 2008-05-12

Toxoplasma gondii is among the most studied parasites worldwide but there not much information about it published in Ireland. The objectives of this study were to determine seroprevalence T. sheep, pigs, deer and chickens molecular detection DNA muscle tissue. Serum samples collected from these species at time slaughter Irish abattoirs during 2007 tested for anti-T. antibodies using a commercial semi-quantitative latex agglutination test. Antibodies (titre ≥1 : 64) found 36% (105/292) 4.7%...

10.1111/j.1863-2378.2012.01514.x article EN Zoonoses and Public Health 2012-06-15

<title>Abstract</title> Background Companion animals are infected with a range of helminth and protozoan parasites which can have significant effect on the health welfare animals. While several diagnostic techniques available to detect parasitic infection in animals, they all vary sensitivity specificity. This study aims estimate performance OvaCyte<sup>TM</sup> Pet Analyser by comparing it established benchmarks commonly used reference laboratories. Methods<bold> </bold>A total 141 canine...

10.21203/rs.3.rs-5717019/v1 preprint EN cc-by Research Square (Research Square) 2025-01-02

Background: Biting midges in the genus Culicoides (Diptera: Ceratopogonidae) act as vectors for several arboviruses, including Bluetongue virus (BTV) and Schmallenberg (SBV), which affect livestock health productivity. In Ireland, limited genetic data are available regarding diversity of species. This study represents first attempt to characterise this region using molecular techniques. Methods: Adult samples were captured Onderstepoort Veterinary Institute (OVI) traps across six locations...

10.1101/2025.01.08.631704 preprint EN cc-by-nd bioRxiv (Cold Spring Harbor Laboratory) 2025-01-08

SUMMARY Natural Cryptosporidium infections in pigs are widespread but generally apathogenic. This study was undertaken to determine the prevalence of zoonotic spp. piggeries Ireland, where drinking water supply is particularly vulnerable contamination with species. Overall, were detected 39 out 342 animals (11·4%), highest infection rates among weaners (15%) and sows (13·3%). Twenty-nine positive samples genotyped based on SSU rRNA sequence analysis. Infections parvum , most important...

10.1017/s0031182007002983 article EN Parasitology 2007-06-13

A harmonized sampling approach in combination with spatial modelling is required to update current knowledge of fasciolosis dairy cattle Europe. Within the scope EU project GLOWORM, samples from 3,359 randomly selected farms 849 municipalities Belgium, Germany, Ireland, Poland and Sweden were collected their infection status assessed using an indirect bulk tank milk (BTM) enzyme-linked immunosorbent assay (ELISA). Dairy considered exposed when optical density ratio (ODR) exceeded 0.3...

10.4081/gh.2015.348 article EN cc-by-nc Geospatial health 2015-03-19

Fasciolosis is generally a subclinical infection of dairy cows and can cause marked economic losses. This study investigated the prevalence spatial distribution fasciolosis in cow herds Ireland using an in-house antibodydetection enzyme-linked immunosorbent assay applied to bulk tank milk (BTM) samples collected during autumn 2012. A total 5,116 BTM were from 4,602 different herds, with 514 farmers submitting two consecutive months. Analysis showed that 82% (n = 3,764) had been exposed...

10.4081/gh.2015.350 article EN cc-by-nc Geospatial health 2015-03-19

&lt;em&gt;Fasciola hepatica&lt;/em&gt; infection challenges health, welfare and productivity of small ruminants throughout the world. The distribution &lt;em&gt;F. in sheep Europe is usually scattered studies are generally concerned with a single area making it difficult to compare results from different environments, climates management regimes. In order elucidate current scenario terms prevalence intensity farms across Europe, standardized cross-sectional survey was conducted three pilot...

10.4081/gh.2015.353 article EN cc-by-nc Geospatial health 2015-03-19
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