Veterinary parasitology最新文献

{"title":"Larval anatomy and intra-puparial development of the camel nasal bot fly, Cephalopina titillator (Diptera: Oestridae)","authors":"Daniel Martín-Vega ,&nbsp;Martin J.R. Hall ,&nbsp;Asha Antony ,&nbsp;Brett Clark ,&nbsp;Robert Barigye ,&nbsp;Temesgen Mohammed ,&nbsp;Layaly Hamdan ,&nbsp;Bojan Gajic","doi":"10.1016/j.vetpar.2025.110476","DOIUrl":"10.1016/j.vetpar.2025.110476","url":null,"abstract":"<div><div>Larvae of the camel nasal bot fly, <em>Cephalopina titillator</em> (Diptera: Oestridae), cause nasopharyngeal myiasis in camels. This myiasis can be severe, even fatal. Here, the morphology of the main organs of second (L2) and third (L3) instar larvae and of the intra-puparial forms are described, using a combination of micro-computed tomography supported by routine histology. For this, L2 and L3 larvae were collected from the heads of slaughtered camels and were either killed and preserved or allowed to pupariate. Pupariated specimens were killed at intervals and larvae and puparia were prepared for micro-CT scanning. Additionally, freshly collected larval specimens were fixed, stained and examined by light microscopy. The most distinctive internal larval structures were the digestive organs, occupying almost 5 % of the internal larval volume. The larval salivary glands were enlarged, with a similar relative volume to other Oestrinae, but they were shorter and did not unite posteriorly in a “glandular band”. The distal region of the Malpighian tubules was also enlarged as in other Oestrinae, but to a lesser degree. The intra-puparial forms showed a gradual reduction of the digestive tract, reflecting the non-feeding behaviour of adults, yet had highly developed reproductive organs facilitating mating soon after eclosion. The morphological and physiological adaptations to parasitism are discussed.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110476"},"PeriodicalIF":2.0,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The GLI3 may be involved in the damage process of Eimeria tenella to chicken cecal tissue","authors":"Wanjiang Xiang ,&nbsp;Ying Chen ,&nbsp;Ye He ,&nbsp;Yongmei Yu ,&nbsp;Ping Li ,&nbsp;Bi Wang ,&nbsp;Zhentao Cheng","doi":"10.1016/j.vetpar.2025.110473","DOIUrl":"10.1016/j.vetpar.2025.110473","url":null,"abstract":"<div><div><em>Eimeria tenella</em> (<em>E. tenella</em>) is the most pathogenic avian coccidial species that targets the cecal epithelial cells of chickens. During the peak period of <em>E. tenella</em> oocyst shedding, the release of a large number of oocysts causes great damage to the cecal tissue. This study uses scanning electron microscopy to observe morphological changes in the host cecum during this period. Subsequently, the metabolic status and transcription level of the cecal tissue were analyzed to gain a comprehensive understanding of the interaction mechanism between <em>E. tenella</em> and the host. The results show substantial cecal tissue damage during the peak oocyst shedding period. The test group shows widespread epithelial cell sloughing, lamina propria exposure, widened intercellular spaces, and a scattered arrangement of absorptive epithelial cells. Combined analysis of the metabolome and transcriptome revealed that primary metabolic pathways, including amino acid metabolism, nucleic acid metabolism and lipid metabolism, were significantly altered in the process of <em>E. tenella</em> damage to cecal tissue. The transcription factor <em>GLI</em>-Kruppel family member 3 (<em>GLI3</em>) may be involved in regulation of primary metabolic pathways through mTORC1 signaling pathway. This study elucidates how <em>E. tenella</em> affects the host through physiological, metabolic and transcriptional changes in chicken cecal tissue. It provides valuable insights into the mechanisms of host immune response and the molecular dynamics of parasite-host interaction.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110473"},"PeriodicalIF":2.0,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrative RNA-Seq analysis of host-parasite interactions and microbiota shifts in the gills of two fish species infected with monogeneans","authors":"Daniel Toala-Franco ,&nbsp;Diana M. Torres-Cifuentes ,&nbsp;Lizeth C. Flores-Méndez ,&nbsp;Víctor Hugo Caña-Bozada","doi":"10.1016/j.vetpar.2025.110472","DOIUrl":"10.1016/j.vetpar.2025.110472","url":null,"abstract":"<div><div>Monogenean infections represent a significant threat to aquaculture by compromising fish health. These parasites can cause severe histological damage and increase mortality rates. The white snook (<em>Centropomus viridis</em>) and the gilthead seabream (<em>Sparus aurata</em>) are two commercially important fish species that become susceptible to diseases when infected with monogeneans. Understanding the molecular mechanisms underlying host responses to infection is essential for developing effective disease management strategies. In this study, we performed an integrative RNA-Seq analysis using transcriptomic datasets from <em>C. viridis</em> and <em>S. aurata</em> infected with the monogeneans <em>Rhabdosynochus viridisi</em> and <em>Sparicotyle chrysophrii</em>, respectively. These datasets originate from three studies, allowing us to investigate host gene expression changes, monogenean gene activation, and microbiota shifts associated with infection. Our analysis of the gill microbiota revealed significant alterations in bacterial composition between infected and uninfected fish. In the microbiota of both <em>C. viridis</em> and <em>S. aurata</em>, eight bacterial families were more abundant in infected fish, whereas eleven and four families, respectively, were more abundant in uninfected fish. In monogeneans, the molecular mechanisms shared across all Bioprojects included extracellular matrix organization, proteolysis, and gluconeogenesis, processes that may be involved in parasite colonization and survival within the host. In fish, our analysis identified shared molecular mechanisms between <em>S. aurata</em> and <em>C. viridis</em>, including oxygen carrier activity, cytokine regulation, bacterial response, and cadherin-mediated adhesion, highlighting a complex interplay between the host immune system, microbiota, and parasite. These findings enhance our understanding of fish-microbiome-parasite interactions and offer valuable perspectives for improving disease control strategies in aquaculture.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110472"},"PeriodicalIF":2.0,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sarcoptic mange in cattle: Effects of treatment with eprinomectin topical solution on performance, behavior changes, and adrenal and systemic responses to ACTH challenge","authors":"Steffen Rehbein,&nbsp;Dietmar Hamel,&nbsp;Martin Visser,&nbsp;Renate Rauh","doi":"10.1016/j.vetpar.2025.110474","DOIUrl":"10.1016/j.vetpar.2025.110474","url":null,"abstract":"<div><div>Bovine sarcoptic mange can cause significant pruritus and skin disease which compromise the health and welfare of the animals, impairs animal productivity and is furthermore of zoonotic concern. This study was conducted to evaluate the effects of efficacious treatment of sarcoptic mange on performance and on animal welfare using behavioral indicators and adrenal reactivity testing.</div><div>Sixteen young cattle with induced sarcoptic mange were allocated by restricted randomization based on body weight to an untreated group (control) or a treated group (eprinomectin 5 mg/mL topical solution [EPRINEX® Pour-On] at Day 0) and monitored for eight weeks after treatment administration (mite counts, lesion scores, anti-<em>Sarcoptes</em> antibodies, feed intake, body weight, 24-hour behavior videotaping, adrenocorticotropic hormone [ACTH] stimulation at Day 58).</div><div>The treated animals became mite-negative four weeks after treatment while all untreated cattle maintained the infestation. The antibody levels followed the mite counts and lesion scores, decreased after treatment in the treated cattle and increased throughout the study in the untreated controls. Over the 8-week post-treatment period, the treated animals gained more weight (81.9 kg vs. 67.8 kg, respectively; p &lt; 0.05) and had a higher feed conversion efficacy (0.203 kg gain/kg feed vs. 0.154 kg gain/kg feed, respectively; p &lt; 0.01). Behavioral activities of the cattle did not differ between the two groups at Day 0. However, at Day 56 treated cattle spent more time lying during 24 hours (p = 0.0754) and did less often rub, kick and lick (p &lt; 0.05) than the untreated cattle. Analysis of the behaviors of Day 0 vs. Day 56 within each group demonstrated no significant difference for any activity in the untreated group, but extension of lying time and reduction of rubbing, kicking and licking (p &lt; 0.05) were observed for the animals treated eight weeks before. The ACTH stimulation indicated reduced adrenal and systemic reactivity in the untreated cattle.</div><div>The efficacious treatment of sarcoptic mange resulted in a substantial increase of the performance of the cattle and effectively alleviated the adverse welfare caused by mange. Analysis of specific behavioral activities and adrenal reactivity testing provided evidence for adverse welfare and impacted metabolic capability due to chronic stress caused by the infestation with mange that can be prevented by efficacious treatment.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110474"},"PeriodicalIF":2.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From selection to resistance: Mitochondrial findings in hookworm evolution under drug pressure","authors":"João Alexsander Silva Costa ,&nbsp;Celi da Silva Medeiros ,&nbsp;Luis Fernando Viana Furtado ,&nbsp;Élida Mara Leite Rabelo","doi":"10.1016/j.vetpar.2025.110470","DOIUrl":"10.1016/j.vetpar.2025.110470","url":null,"abstract":"<div><div>Single nucleotide polymorphisms (SNPs) in codons 134, 167, 198, and 200 of the <em>β-tubulin</em> isotype 1 gene are associated with benzimidazole resistance in nematodes. Our group previously selected an <em>Ancylostoma ceylanicum</em> strain resistant to albendazole through drug-induced selective pressure, derived from a wild-type strain maintained under laboratory conditions for over 15 years. This study aimed to investigate mitochondrial genetic variability in the resistant strain compared to its wild-type counterpart. A total of 151 worms from both strains, collected during and 42 months after the selection process, were analyzed for partial sequences of the mitochondrial COI and NAD1 genes. Nucleotide variations were detected exclusively in the resistant strain, with low divergence levels of 0.16 % (1/612 bp) in COI and 0.25 % (1/398 bp) in NAD1. All COI substitutions were synonymous, while NAD1 presented one nonsynonymous mutation. Phylogenetic analyses based on Maximum Likelihood and Bayesian inference revealed strong clustering between resistant and wild-type laboratory samples (COI: 99 % bootstrap; NAD1: 96 %), distinct from field-derived sequences. These findings suggest that genetically homogeneous populations, resulting from isolation and restricted gene flow, may be more susceptible to genetic pressures, including selection, potentially leading to the establishment of resistant parasites. This study underscores the role of population genetics in the evolution of drug resistance and emphasizes the importance of managing genetic diversity to mitigate resistance development.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110470"},"PeriodicalIF":2.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Yellow mealworm beetle (Tenebrio molitor) larvae as an alternative model for antileishmanial drug evaluation","authors":"Michel Muálem de Moraes Alves ,&nbsp;Victoria Hannah Araújo de Almeida Passos ,&nbsp;Paulline Paiva Mendes de Souza Leal ,&nbsp;Pastora Pereira Lima Neta ,&nbsp;Bianca Soriano dos Anjos ,&nbsp;Boris Timah Acha ,&nbsp;Jose Moreira Tavares Neto ,&nbsp;José Otávio Carvalho Sena de Almeida ,&nbsp;Leonardo da Rocha Sousa ,&nbsp;Daniel Dias Rufino Arcanjo ,&nbsp;Klinger Antonio da Franca Rodrigues ,&nbsp;Fernando Aécio de Amorim Carvalho ,&nbsp;Gad Baneth","doi":"10.1016/j.vetpar.2025.110468","DOIUrl":"10.1016/j.vetpar.2025.110468","url":null,"abstract":"<div><div>Leishmaniasis is zoonotic disease caused by parasites of the genus <em>Leishmania</em>. Available treatments are limited and are associated with a range of adverse effects. The search for potential new drugs involves both <em>in vitro</em> and <em>in vivo</em> assays. Rodents are primarily employed as experimental models for <em>in vivo</em> assays. However, this practice raises ethical concerns, including issues related to environmental impact and animal welfare. Therefore, various alternative methods have emerged to avoid or reduce the use of mammals in laboratories for preclinical trials. The aim of this study was to evaluate <em>Leishmania amazonensis</em> infection in yellow mealworm (<em>Tenebrio molitor</em>) larvae. <em>T. molitor</em> larvae were infected with promastigotes (1 ×10⁵; 1 ×10⁶; and 1 ×10⁷) and assessed through survival curves, degree of melanization, parasitic load, cell proliferation, and oxidative stress levels measured by reduced Glutathione (GSH) and nitrite levels. <em>Leishmania</em> promastigotes which invaded <em>T. motilor</em> plasmatocytes transformed into intracellular amastigotes. Ten percent of larval death was observed after 24 hours in larvae that received 1 × 10⁵ and 1 × 10⁶ promastigotes and 20 % mortality was found for those that received 1 × 10⁷. The parasitic load revealed approximately 1750 parasites/larva infected with the highest concentration. Furthermore, the larvae showed a cellular response pattern similar to that seen in vertebrate host infections, with increased cell proliferation, activation of plasmatocytes, and elevated GSH and nitrite levels. This is the first study to establish <em>T. molitor</em> larvae as an alternative model for investigating <em>Leishmania</em> pathogenesis in invertebrates, proposing its use in preclinical trials for exploring potential new drugs to combat leishmaniasis.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110468"},"PeriodicalIF":2.0,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neospora caninum triggers the release of heterophil extracellular traps in chickens","authors":"Zhengkai Wei ,&nbsp;Yuqian Jiang ,&nbsp;Xinxin Gao ,&nbsp;Yuxiao Qian ,&nbsp;Dezhi Zhang ,&nbsp;Qianyong Li ,&nbsp;Quan Liu","doi":"10.1016/j.vetpar.2025.110471","DOIUrl":"10.1016/j.vetpar.2025.110471","url":null,"abstract":"<div><div><em>Neospora caninum (N. caninum)</em> has been recognized as a pathogen responsible for neosporosis in chicken. Heterophils, which are a crucial part of the chicken's innate immune response, employ heterophil extracellular traps (HETs) as a principal defense strategy against invading pathogens. However, whether <em>N. caninum</em> can trigger the release of HETs remains unclear. This study presents the first evidence that <em>N. caninum</em> can induce the release of HETs in chickens and delves into the mechanisms that regulate this phenomenon. The impact of <em>N. caninum</em> on heterophil activity was evaluated using the CCK-8 assay. <em>N. caninum</em>- induced HETs were characterized using scanning electron microscopy and immunofluorescence. The release of <em>N. caninum</em>-induced HETs was quantified using a PicoGreen-based fluorescence microplate assay. Our findings revealed that heterophil activity remained unaffected by <em>N. caninum</em> infection. <em>N. caninum</em> induced thicknesses, reminiscent of HET-like structures, which primarily consisted of a DNA skeleton, citrullinated histone (citH3), and elastin. Furthermore, an increase in reactive oxygen species (ROS) production was detected during the release of <em>N. caninum</em>-induced HETs, a process that was found to be dependent on ROS-mediated activation, NADPH oxidase activity, glycolysis, toll-like receptor 2/4 (TLR2/4) and MAPK signaling pathways. <em>N. caninum</em> induced-HETs release was shown to be ROS-dependent, involving the activation of NADPH oxidase, ERK_1/2, glycolysis, p38 MAPK, and toll-like receptor signaling pathways. In conclusion, this study is the first to elucidate the release mechanism of <em>N. caninum</em>-induced HETs in chicken, offering significant insights into the mechanisms underlying immune innate system against <em>N. caninum</em> infection.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"337 ","pages":"Article 110471"},"PeriodicalIF":2.0,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recombinant Cryptosporidium parvum GP15 based enzyme linked immunosorbent assay for detection of exposure of bovine populations to Cryptosporidium","authors":"Ajayta Rialch ,&nbsp;Opinder Krishen Raina ,&nbsp;Partha Sarathi Banerjee ,&nbsp;Gorakh Mal ,&nbsp;Birbal Singh ,&nbsp;Rinku Sharma ,&nbsp;Gauri Jairath ,&nbsp;Devi Gopinath ,&nbsp;Rajendra Damu Patil ,&nbsp;Savita Chaudhary ,&nbsp;Rajesh Chahota ,&nbsp;M. Sankar ,&nbsp;Rajat Garg","doi":"10.1016/j.vetpar.2025.110467","DOIUrl":"10.1016/j.vetpar.2025.110467","url":null,"abstract":"<div><div>The serodiagnostic potential of recombinant <em>Cryptosporidium parvum</em> glycoprotein 15 (rCpGP15) was evaluated in Enzyme Linked Immunosorbent Assay (ELISA) in the detection of exposure of bovines to <em>Cryptosporidium</em> species in Himachal Pradesh and Uttarakhand states of North India. The 11.13 kDa rCpGP15 was expressed in pET-32a (+) transformed <em>E. coli</em> BL21 cells and was purified by Ni-NTA affinity chromatography as polyhistidine tagged fusion protein of ∼ 32 kDa. Its immunogenicity was checked in western blot using rabbit antisera raised to the recombinant antigen and bovine sera naturally infected with <em>Cryptosporidium</em>. Two hundred and forty-six bovines were screened for <em>Cryptosporidium</em> spp. oocysts in faecal samples by modified-Ziehl Neelson technique and their sera were used for ELISA standardization. The rCpGP15 based indirect IgG-ELISA was standardized with 83 % sensitivity, 78.3 % specificity where ELISA cut-off and accuracy were decided using ROC curve analysis. The percent accuracy was 79.19 %, with area under the Receiver Operating Characteristic (ROC) curve value 0.827 depicting the moderate accuracy of the assay. Additionally, sera from <em>Eimeria</em> (n = 3), strongyles (n = 3), <em>Babesia</em> (n = 2), <em>Theileria</em> (n = 5), <em>Trypanosoma</em> (n = 2) and <em>Anaplasma</em> (n = 5) positive animals showed no seroreactivity. The diagnostic performance of rCpGP15 protein in differentiating <em>Cryptosporidium</em> species was predicted through <em>in-silico</em> B cell epitope prediction, homology modelling and structural comparison of GP15 protein from <em>C. parvum, C. hominis, C. bovis</em> and <em>C. ryanae.</em> Four linear antigenic epitopes were predicted in CpGP15 protein sequence by SVMTrip. The overall root mean square deviation (RMSD) values during homology modelling and structural comparison of CpGP15 and <em>C. hominis, C. bovis</em> and partial <em>C. ryanae</em> GP15 were 2.093 Å, 3.759 Å and 1.152 Å, respectively. The serodiagnostic assay developed in the present study has moderate accuracy and can be applied in serosurveillance of large bovine populations. It is capable of detecting asymptomatic animals with intermittent oocyst shedding which will further be helpful for better understanding the disease dynamics and for the timely control of cryptosporidiosis.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"336 ","pages":"Article 110467"},"PeriodicalIF":2.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence of spurious parasites identified in feces of dogs and correlation with true canine parasitism","authors":"Yoko Nagamori ,&nbsp;Zephran Warren ,&nbsp;Melissa Houma ,&nbsp;Nishantha Samarakoon","doi":"10.1016/j.vetpar.2025.110466","DOIUrl":"10.1016/j.vetpar.2025.110466","url":null,"abstract":"<div><div>Spurious parasites are commonly found in canine feces as dogs often practice coprophagy, predation, and scavenging behaviors. Our main study objectives were to determine the prevalence and variety of spurious parasites identified in feces of client-owned dogs and a possible correlation between the prevalence of spurious and true parasites in dogs. Additionally, the prevalence of spurious parasites was statistically compared by age, sex, and reproductive status of dogs and regions. A total of 48,509 fecal examination results were retrieved from Zoetis Reference Laboratories in Louisville, Kentucky, from January 1 to December 31, 2023, and included for the study. The most frequently identified spurious parasite was <em>Eimeria</em> oocysts (4.14 %), followed by non-canine strongylid eggs (0.97 %), Anoplocephalidae eggs (0.33 %), <em>Monocystis</em> oocysts (0.27 %), free-living mites (0.13 %), avian ascarid eggs (0.12 %), free-living nematode eggs and larvae (0.08 %), <em>Adelina</em> and other spurious coccidian oocysts (0.06 %), spurious <em>Capillaria</em> eggs (0.05 %), spurious <em>Trichuris</em> eggs (0.04 %), Dipteran eggs and larvae (0.02 %), spurious lungworm larvae (0.02 %), <em>Strongyloides</em> eggs (0.01 %), <em>Toxocara cati</em> eggs (0.01 %), and <em>Syngamus</em> eggs (0.01 %). Dogs that excreted spurious parasites in feces showed a significantly higher risk for true canine parasitism (<em>P</em> &lt; 0.0001), and synchronizing monthly differences were observed between the prevalence of spurious and true parasites (<em>P</em> = 0.0022). The prevalence of spurious parasite was influenced by age, sex, and reproductive status of dogs and regions. Frequent fecal examinations are recommended for dogs that shed spurious parasites in feces.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"336 ","pages":"Article 110466"},"PeriodicalIF":2.0,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143823957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ivermectin performance against equine strongylids: Efficacy, egg reappearance periods, and fecal egg counting method comparison","authors":"Martin K. Nielsen ,&nbsp;Isabella D. Bartholdy ,&nbsp;Katja S. Kristensen ,&nbsp;Josefine C. Borrye ,&nbsp;Kirstine S.S. Meilvang ,&nbsp;Camilla E.K. Rendtorff ,&nbsp;Michelle D. Hjortflod ,&nbsp;Vibeke Fuglbjerg ,&nbsp;Malin Karlsson ,&nbsp;Henrik H. Petersen ,&nbsp;Katrine Toft ,&nbsp;Stig M. Thamsborg ,&nbsp;Tina H. Pihl","doi":"10.1016/j.vetpar.2025.110465","DOIUrl":"10.1016/j.vetpar.2025.110465","url":null,"abstract":"<div><div>Equine strongylids are ubiquitous and can cause severe health issues. Anthelmintic resistance is widely common in cyathostomin parasites, and recent studies have documented increasing incidence of resistance to the macrocyclic lactone drug class. Several European countries have implemented prescription-only restrictions of anthelmintic usage by law to reduce anthelmintic treatment intensity and decrease the selection pressure for drug resistance. However, long term outcomes of this approach have not been thoroughly evaluated. The aim was to determine ivermectin efficacy in strongylids by means of faecal egg count reduction test (FECRT) and egg reappearance period (ERP) in Danish horses, compare two fecal egg count techniques, and determine the prevalence of <em>Strongylus vulgaris</em> in the study population. Herds and horses were selected by four collaborating veterinary practices. A total of 299 horses from 30 herds were enrolled in the study. Fecal egg counts (FEC) were determined using a concentration McMaster technique as well as an artificial intelligence-based automated fecal egg counting system. All horses with FEC &gt; 0 eggs per gram of feces (EPG) were treated with ivermectin. Ivermectin efficacy and ERP were determined following current guidelines. Coproculture and PCR were employed for detection of <em>S. vulgaris</em>. FECRTs based on McMaster egg counts suggested inconclusive ivermectin efficacy in two equine operations and full efficacy in all remaining populations, whereas the automated system suggested ivermectin resistance in 6 operations and inconclusive results in another 8. Ivermectin ERP was determined to be at least 8 weeks with both methods in all cases. The prevalence of <em>S. vulgaris</em> was 2.7 % and 5.7 % with coproculture and PCR, respectively, and all samples were negative with both methods at 8 and 24 weeks post treatment. In general, ivermectin efficacy was high, although some results suggest that reduced efficacy could be occurring, which warrants further monitoring going forward. The ERP estimates all exceeded 8 weeks, which suggests that no reduction has occurred. The two egg counting techniques were in general agreement, but the automated system detected more positives at low egg count levels, which led to lower efficacy estimates in some populations. <em>Strongylus vulgaris</em> remains enzootic in Danish horses.</div></div>","PeriodicalId":23716,"journal":{"name":"Veterinary parasitology","volume":"336 ","pages":"Article 110465"},"PeriodicalIF":2.0,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}