Parasites are organisms that live on or within a host, deriving nutrients at the host's expense. In horses, parasitic infections can affect various systems, including the gastrointestinal tract, skin, and respiratory system. Common equine parasites include strongyles, ascarids, tapeworms, and bots. These parasites can lead to a range of health issues, from mild discomfort to severe disease, depending on the type and burden of the infestation. This page compiles peer-reviewed research studies and scholarly articles that explore the biology, life cycle, and impact of parasites on equine health, as well as strategies for diagnosis, treatment, and prevention of parasitic infections in horses.
Coultous R, Gotić J, McCann M, Sutton D, Beck R, Shiels B.The apicomplexan haemoparasite Theileria equi, a causative agent of equine piroplasmosis, is an established pathogen of significant welfare and economic concern within the Croatian equine population. A previous large surveillance study of T. equi has identified two distinct parasite populations, one in the north and one in the south, geographically separated by the Dinaric Alps, which traverse the country. This study aimed to further investigate the genetic diversity within these two populations, focussing on allelic variability of the equi merozoite antigen gene, ema-1. Methods: Following nes...
Zamarchi TBO, Henriques AL, Krolow TK, Krüger RF, Rodrigues GD, Munari A, Pessoa FAC, Camargo ELMA.Tabanidae is one of the most diverse families of hematophagous dipterans. Tabanids, in general, are mechanical vectors of some pathogens. Given the vector importance and the lack of knowledge of the tabanid fauna in horses in Amazon Forest fragments of the state of Rondônia, this work aimed to determine the season that the different species of horse flies prefer to carryout hematophagy on horses and verify whether the horse fly community remains the same throughout the year. The sampling areas for tabanid captures were in the municipality of Monte Negro, Western Amazon, Brazil. Four new occur...
Nielsen MK.Anthelmintic resistance is reported in equine nematodes with increasing frequency in recent years, and no new anthelmintic classes have been introduced during the past 40 years. This manuscript reviews published literature describing anthelmintic resistance in cyathostomins, Parascaris spp., and Oxyuris equi with special emphasis on larvicidal efficacy against encysted cyathostomin larvae and strongylid egg reappearance periods (ERP). Resistance to benzimidazoles and pyrimidines is highly prevalent in cyathostomin populations around the world, and macrocyclic lactone resistance has been docume...
Pawlas-Opiela M, Jawor P, Galli J, Zak-Bochenek A, Gorczykowski M, Galli J, Sołtysiak Z, Stefaniak T.Infection with Gasterophilus intestinalis (botfly) larvae often occurs in horses. The aim of the study was to isolate the larvae of G. intestinalis and evaluate the serum and salivary humoral immune response using self-developed ELISA in G. intestinalis infected horses. Blood serum or saliva samples were taken from 125 infected horses and 54 uninfected slaughtered horses. The antigens from G. intestinalis larvae were used for development of ELISA in order to evaluate the intensity of G. intestinalis IgG, IgM, and IgA antibody reactivity in the serum or saliva of naturally infected horses and h...
D'Anza E, Buono F, Albarella S, Castaldo E, Pugliano M, Iannuzzi A, Cascone I, Battista E, Peretti V, Ciotola F.The Pony of Esperia is an Italian autochthonous horse breed reared in the wild on the Aurunci and Ausoni Mountains. Currently, it is considered an endangered breed, as its population consists of 1623 animals. It is therefore essential to identify all aspects that can improve the management and economy of its breeding, favoring its diffusion. In this paper, the effects of intestinal strongyle infection on the chromosome stability of peripheral blood lymphocytes (PBLs) was evaluated through aneuploidy and chromosome aberration (gap, chromatid and chromosome breaks, and the number of abnormal cel...
Nielsen MK, Steuer AE, Anderson HP, Gavriliuc S, Carpenter AB, Redman EM, Gilleard JS, Reinemeyer CR, Poissant J.Macrocyclic lactones have been the most widely used drugs for equine parasite control during the past four decades. Unlike ivermectin, moxidectin exhibits efficacy against encysted cyathostomin larvae, and is reported to have persistent efficacy with substantially longer egg reappearance periods. However, shortened egg reappearance periods have been reported recently for both macrocyclic lactones, and these findings have raised several questions: (i) are egg reappearance period patterns different after ivermectin or moxidectin treatment? (ii) Are shortened egg reappearance periods associated w...
McTigue FE, Mansbridge SC, Pyatt AZ.Equine anthelmintic resistance poses a threat to the health and welfare of horses worldwide. With no new imminent anthelmintic classes, it is vital to decrease the resistance rate and preserve available classes. Traditional indiscriminate anthelmintic use is not synonymous with a strategic control ideology; however, many continue to implement outdated practices. In comparison to livestock farmers, there have been few social science studies examining horse owner behaviours. This study aimed to understand the perceived barriers faced by horse owners and yard managers to adopting a strategic appr...
Graham H, van Kalsbeek P, van der Goot J, Koene MGJ.Equine piroplasmosis (EP) is a tick-borne disease affecting horses, donkeys, mules and zebras, caused by the intracellular apicomplexan protozoa and . The geographical distribution of EP is closely related to the distribution of its vector tick species belonging to the genera of and . Since the discovery of ticks in 2007 and the first reported autochthonous cases in the South of the Netherlands in 2012, no data on the (sero)prevalence of EP in horses in the Netherlands have been reported and it remains unclear whether and have been able to establish themselves in the Netherlands. This stu...
Mimoun L, Steinman A, Kliachko Y, Tirosh-Levy S, Schvartz G, Blinder E, Baneth G, Mazuz ML.Equine Neospora infection has been linked to neurological disorders and infertility in horses. This study looked into the risk factors for infection and the exposure to Neospora spp. in horses. The study was performed in two independent populations in Israel. The first consisted of apparently healthy horses, and the second consisted of mares examined during pregnancy and after parturition. Sera samples collected from horses and mares were tested for Neospora exposure by the indirect fluorescent antibody test (IFAT). The study revealed seroprevalence of 24% in apparently healthy horses and 66.4...
Sargison N, Chambers A, Chaudhry U, Costa Júnior L, Doyle SR, Ehimiyein A, Evans M, Jennings A, Kelly R, Sargison F, Sinclair M, Zahid O.Understanding the composition of gastrointestinal nematode communities may help to mitigate or exploit parasite adaptations within their host. We have used nemabiome deep amplicon sequencing of internal transcribed spacer-2 (ITS-2) ribosomal DNA to describe the temporal and host species composition of gastrointestinal nematode communities following sampling of six Scottish ponies across 57 months. In the absence of parasite control, each horse showed seasonal trends of increases and decreases in faecal egg counts, consistent with the epidemiology of equine strongylid parasites, however, the c...
Duncan KT, Sundstrom KD, Hunt D, Lineberry MW, Grant A, Little SE.Although ticks are known vectors of pathogens across a range of hosts, there is limited research on emerging tick-borne diseases of horses in the United States. Tick surveys from other regions suggest Rickettsia spp. and Ehrlichia spp. may be clinically relevant in horses. To better understand the transmission risk of these tick-borne rickettsial disease agents to horses, ticks were collected from horses in Oklahoma. Ticks for the current study (306 Amblyomma americanum, 20 Dermacentor albipictus, 19 D. variabilis, and 7 A. maculatum) were evaluated for Rickettsia spp. and Ehrlichia spp. using...
Hwang H, Ro Y, Lee H, Kim J, Lee K, Choi EJ, Bae YC, So B, Kwon D, Kim H, Lee I.Since 2013, the number of requests for diagnosis for horses based on neurological symptoms has increased rapidly in South Korea. The affected horses have commonly exhibited symptoms of acute seasonal hindlimb ataxia. A previous study from 2015-2016 identified as the causative agent. Objective: This study is an epidemiological investigation to find out risk factors related to the rapid increase in hindlimb ataxia of horses due to aberrant parasites in South Korea. Methods: An epidemiological investigation was conducted on 155 cohabiting horses in 41 horse ranches where the disease occurred. Th...
Zahoor J, Kashif M, Nasir A, Bakhsh M, Qamar MF, Sikandar A, Rehman A.Trypanosomiasis is one of the severe pathogenic infections, caused by several Trypanosoma species, affecting both animals and humans, causing substantial economic losses and severe illness. The objective of this study was to determine the molecular diagnosis and the risk factors associated with trypanosomiasis in District Jhang, Punjab, Pakistan. For this purpose, blood samples were randomly collected from 200 horses. A predesigned questionnaire was used to collect data on risk factors before the sample collection. The microscopy examination through Giemsa staining, formol gel test and PCR tec...
The genus includes species with a wide geographical spread that cause pathology in humans and animals. In this context, an epidemiological study of infection was carried out in the northeastern part of Romania to investigate for the first time the prevalence of this infection in pigs, horses, wild boars and bears, the geographical distribution of species and the natural reservoir of infection. Between 2010 and 2015, a total of 166,270 animals were examined by the method of artificial digestion, in order to calculate the annual and general prevalence of infection, according to the host and...
Dauparaitė E, Kupčinskas T, Varady M, Petkevičius S.Control of strongyle infections presents a global challenge for horse practitioners due to the development of anthelmintic resistance (AR), however comprehensive information on AR in Lithuania is still lacking. The aim of this study was to assess the current situation of fenbendazole (FBZ) AR in horses at stable level in Lithuania. Results: Faecal samples from 121 horses from six stables were examined using the Mini-FLOTAC method. Of these, 89 horses met the inclusion criteria that included strongyle faecal egg counts (FEC) exceeding 200 eggs per gram (EPG). Faecal egg count reduction tests (F...
Sands B, Lihou K, Lait P, Wall R.The emergence of Babesia pathogens novel to the UK is of growing concern; these include Babesia canis and Babesia caballi. However, a better understanding of changes in the prevalence of endemic Babesia species such as Babesia venatorum and Babesia divergens is also of importance. Here, the prevalence of Babesia pathogens in both Dermacentor reticulatus and Ixodes ricinus ticks was assessed. Dermacentor reticulatus were collected from six sites known to harbour populations of this species in west Wales and southern England. DNA was extracted from 879 individual ticks and subjected to PCR and s...
Anstey SI, Jenkins C, Jelocnik M.Chlamydia psittaci is a recognised cause of late-term equine foetal loss and poses a zoonotic risk in Australia. However, a management strategy is lacking to protect at-risk humans handling infected aborted material and pregnant mares. This study proposes a protocol for approaching C. psittaci foetal loss after investigating four foetal losses that occurred on a horse stud in the Hunter Valley, Australia in 2021. Swabs from the foetal loss cases (n = 4), close contact mares (n = 59), and foals of the close contact mares (n = 33) were collected and tested for C. psittaci using both isothe...
Abo-Aziza FAM, Hendawy SHM, Abdullah HHAM, El Namaky A, Laidoudi Y, Mediannikov O.Equine filariosis (EF) is a neglected vector-borne disease caused by nematode species belonging to the Onchocercidae and Setariidae families. Aside from their zoonotic potential, some species are responsible for serious health problems in equids worldwide, leading to significant economic difficulties. Here, we molecularly investigated equine blood samples (320 horses and 109 donkeys from Egypt) and four adult worms isolated from the peritoneal cavity of 5 out of the 94 slaughtered donkeys. In addition, quantitative enzyme-linked immunoassays (ELISAs) targeting circulating cytokines were used t...
Cain JL, Nielsen MK.The equine ascarids, Parascaris spp., are important nematode parasites of juvenile horses and were historically model organisms in the field of cell biology, leading to many important discoveries, and are used for the study of chromatin diminution. In veterinary parasitology, Parascaris spp. are important not only because they can cause clinical disease in young horses but also because they are the only ascarid parasites to have developed widespread anthelmintic resistance. Despite this, much of the general biology and mechanisms of anthelmintic resistance are poorly understood. This review co...
Alemayehu MT, Abebe BK, Haile SM.Horses are used for a variety of purposes in Ethiopia. However, their service is hampered by a variety of health issues. Strongylosis is a parasitic infestation of the gastrointestinal tract that has a significant impact on the working ability, reproductive performance, well-being, and welfare of horses. The existence of Strongylosis in the study area is reported from clinical cases; however, its prevalence has not been well studied. Unassigned: The current study was carried out from January 2019 to July 2019, to determine the prevalence and associated risk factors of Strongyle in horses in an...
Silva CJD, Lima KPB, Monteiro JFDCLS, Silva AKSFD, Silva FJD, Pereira AMS, Hernandes VP, Silva EDD, Silva CSAGE, Brandão Filho SP, Brito MEF.American cutaneous leishmaniasis is a commonly neglected, vector-borne tropical parasitic disease that is a major public health concern in Brazil. Leishmania (Viannia) braziliensis is the main species associated with the disease. Accurate diagnosis is based on epidemiological surveillance, clinical assessment, and laboratory testing. Leishmania (V.) braziliensis has been detected in several wild and synanthropic mammals. Their epidemiological role has not been entirely elucidated. This study aimed to assess potential L. braziliensis infections in asymptomatic domestic animals, by molecular and...
Chicca J, Cazeault NR, Rus F, Abraham A, Garceau C, Li H, Atwa SM, Flanagan K, Soto ER, Morrison MS, Gazzola D, Hu Y, Liu DR, Nielsen MK, Urban JF....Bacillus thuringiensis (Bt) is a Gram-positive soil bacterium that is widely and safely applied in the environment as an insecticide for combatting insect pests that damage crops or are disease vectors. Dominant active ingredients made by Bt are insect-killing crystal (Cry) proteins released as crystalline inclusions upon bacterial sporulation. Some Bt Cry proteins, e.g., Cry5B (formally Cry5Ba1), target nematodes (roundworms) and show exceptional promise as anthelmintics (cures for parasitic nematode diseases). We have recently described inactivated bacteria with cytosolic crystal(s) (IBaCC) ...
Zhang M, Wei K, Wu Z, Sun J, Hu J, Deng S, Tao J.There is considerable confusion concerning the relationships among species of Sarcocystis found in donkeys and horses. Here, we describe a Sarcocystis species in Chinese donkeys (Equus asinus). Sarcocysts were found in 12 of 32 (37.5%) adult donkeys. By light microscopy, they were divided into two types, thin-walled and thick-walled. The thin-walled were macroscopic (up to 320 μm wide) and had short club-like protrusions (up to 2.7 μm long); the thick-walled were microscopic (up to 135 μm wide) and had villar protrusions (up to 5.4 μm long). Ultrastructures of the two types exhibited s...
Steuer AE, Scoggin K, Stewart JC, Barker VD, Adams AA, Loynachan AT, Nielsen MK.This study aimed to collect information on local and systemic inflammatory responses, and goblet cell-associated components, following anthelmintic treatment with moxidectin and ivermectin in horses naturally infected with cyathostomin parasites. Thirty-six horses aged 2-5 years of age were randomly allocated to three groups. Group 1 received ivermectin/praziquantel (0.2 mg/kg), Group 2 received moxidectin/praziquantel (0.4 mg/kg) and Group 3 were untreated controls. Tissue samples from the Cecum, Dorsal and Ventral Colons were used for histopathological evaluation and preserved for RNA is...
Smith MA, Carpenter AB, Nielsen MK.Essentially all grazing horses are infected with cyathostomin parasites. Adult cyathostomins reside in the large intestine of the horse and larval stages encyst within intestinal mucosa. Manual worm collection from aliquots of intestinal content is the current gold standard for retrieval and enumeration of luminal parasites, however, no research has been conducted to standardize specific parameters for processing and storage of samples. The aims of this study were (1) to evaluate the precision of current standard operating procedures for enumeration of luminal adult cyathostomin populations, (...
Liang W, Zhao S, Wang N, Tang Z, Zhao F, Liu M, Jin W, Meng Y, Jia L.Toxoplasma gondii, one of the important zoonotic parasites, has been detected in lots of hosts including humans, with a widespread prevalence. The products of equids, such as meat and milk, have been closely related to humans' life. As the intermediate hosts, little is known about equids toxoplasmosis in Jilin province. Therefore, the present study aimed to evaluate the occurrence and risk factors of Toxoplasma gondii infections in equids from Jilin, northeastern China. In this study, a total of 245 blood samples of equids (192 horses, 25 donkeys and 28 mules) were collected from six localitie...
Dias De Castro LL, Oliveira Júnior GA, Perez BC, Carvalho ME, De Souza Ramos EA, Ferraz JBS, Molento MB.Cyathostomins are considered one of the most important parasites of horses. A group of horses within a herd can be responsible for eliminating the majority of parasite eggs. This phenotype might be explained by genetic factors. This study aimed to identify genomic regions associated with fecal egg count (FEC) and hematological parameters by performing a genomic-wide association study (GWAS) in Thoroughbred horses naturally infected with cyathostomins. Packed cell volume (PCV), differential leukocyte, and FEC were determined from 90 horses. All animals were genotyped using the Illumina Equine 7...
Gupta S, Vohra S, Sethi K, Gupta S, Kumar S, Kumar R.The kinetoplastid protozoan parasite, Trypanosoma evansi causes a fatal disease condition known as Surra in equines throughout the globe. Disease condition being acute in nature, entrust a huge economic and health impact on the equine industry. Till date, quinapyramine methyl sulphate (QPS) is the first line of treatment and a panacea for the T. evansi infection in equines. Still after the >70 years of its discovery, there is no clue about the mode of action of QPS in T. evansi. The establishment of in vitro cultivation of T. evansi in HMI-9 media has provided opportunity to study the alte...
MacKay RJ, Howe DK.Advances in the understanding of equine protozoal myeloencephalitis (EPM) are reviewed. It is now apparent that EPM can be caused by either of 2 related protozoan parasites, Sarcocystis neurona and Neospora hughesi, although S neurona is the most common etiologic pathogen. Horses are commonly infected, but clinical disease occurs only infrequently; the factors influencing disease occurrence are not well understood. Epidemiologic studies have identified risk factors for the development of EPM, including the presence of opossums and prior stressful health-related events. Attempts to reproduce EP...
MacKay RJ, Howe DK.Advances in the understanding of equine protozoal myeloencephalitis (EPM) are reviewed. It is now apparent that EPM can be caused by either of 2 related protozoan parasites, Sarcocystis neurona and Neospora hughesi, although S neurona is the most common etiologic pathogen. Horses are commonly infected, but clinical disease occurs only infrequently; the factors influencing disease occurrence are not well understood. Epidemiologic studies have identified risk factors for the development of EPM, including the presence of opossums and prior stressful health-related events. Attempts to reproduce EP...
Mfitilodze MW, Hutchinson GW.A postmortem survey of 57 horses in tropical northern Queensland revealed 41 (89%) infected with intestinal strongyles. Thirty-five strongyle species (8 large strongyles and 27 small strongyles [Cyathostominae]) were recorded of which 9 species are reported from Australia for the first time. The 14 most prevalent small strongyles were Cyathostomum catinatum (in 76% of horses), Cyathostomum coronatum (65%), Cyathostomum pateratum (33%), Cyathostomum labiatum (30%), Cylicostephanus calicatus (70%), Cylicostephanus longibursatus (67%), Cylicostephanus goldi (43%), Cylicostephanus minutus (26%), C...
Liu SH, Li K, Hu DF.A survey was conducted on the detection of the larval Gasterophilus species in 90 equines via necropsy or after administering oral ivermectin in Xinjian, China, from 2008 to 2013. All 90 (100%) equines were infested by larval Gasterophilus, and 3723second instar larvae (L2) and 63,778 third instar larvae (L3) were collected from faecal samples and the digestive tract, a ratio of L2:L3=1:17. Over 84.45% of the animals contained ≤1500 larvae and 7.78% had >2000 larvae. The highest totals of L2 and L 3 larvae in any one animal were 1208 in Mongolian wild ass (Equus hemionus hemionus), 2491 in P...
García-Bocanegra I, Cabezón O, Arenas-Montes A, Carbonero A, Dubey JP, Perea A, Almería S.Antibodies to Toxoplasma gondii were determined in serum samples from 616 equids (454 horses, 80 mules and 82 donkeys) in a cross-sectional study of 420 herds in Andalusia (Southern Spain), the region with the highest number of equids in Spain. Antibodies to T. gondii were found in 10.8% horses, 15.0% mules and 25.6% donkeys by using the modified agglutination test (MAT) at a cut-off of 1:25. Herd seroprevalence for horses, mules and donkeys was 14.7% (48/327), 23.9% (11/46) and 34.0% (16/47), respectively, and 75 herds (17.8%) had at least one seropositive animal. Significant differences in T...
Dowdall SM, Matthews JB, Mair T, Murphy D, Love S, Proudman CJ.Equine clinical larval cyathostominosis is caused by simultaneous mass emergence of previously inhibited larvae from the mucosa of the colon. Clinical signs include diarrhoea, colic, weight loss and malaise, and in up to 50% of cases, the disease results in death. Cyathostominae spend a large part of their life cycle as larval stages in the intestinal mucosa. Definitive diagnosis is difficult due to the lack of diagnostic methods for pre-patent infection. In the present study, the enzyme-linked immunosorbent assay (ELISA) was used to investigate isotype responses to larval cyathostominae somat...
Nielsen MK, Branan MA, Wiedenheft AM, Digianantonio R, Garber LP, Kopral CA, Phillippi-Taylor AM, Traub-Dargatz JL.The widespread occurrence of anthelmintic resistance in equine parasites across the world has led to recommendations of fecal egg count-based parasite programs to reduce treatment intensity and thereby delay further development of resistance as much as possible. The most recent study describing equine parasite control in the United States was conducted 20 years ago, and little is known about current strategies employed. This study was part of the National Animal Health Monitoring Systems (NAHMS) Equine 2015 Study, and aimed to describe equine parasite control strategies in the U.S. and evalu...
Rosales R, Rangel-Rivas A, Escalona A, Jordan LS, Gonzatti MI, Aso PM, Perrone T, Silva-Iturriza A, Mijares A.The focus of this study was the detection of equine piroplasmosis in Distrito Capital, Miranda, Aragua, Guárico and Apure States from Venezuela, using two methods: Competitive-Inhibition ELISA and multiplex PCR and the analysis of the possible differences in occurrence in relation to the primary purpose of the horses, which is related to varied degrees of exposure to tick. Antibody levels to Babesia caballi and Theileria equi were assessed in 694 equine serum samples using Competitive-Inhibition ELISA, while PCR assays were performed in 136 horses, using two sets of oligonucleotides to establ...
Braga FR, Araújo JV, Silva AR, Araujo JM, Carvalho RO, Tavela AO, Campos AK, Carvalho GR.The viability of a fungal formulation using the nematode-trapping fungus Duddingtonia flagrans was assessed for the biological control of horse cyathostomin. Two groups (fungus-treated and control without fungus treatment), consisting of eight crossbred mares (3-18 years of age) were fed on Cynodon sp. pasture naturally infected with equine cyathostome larvae. Each animal of the treated group received oral doses of sodium alginate mycelial pellets (1g/(10 kg live weight week)), during 6 months. Significant reduction (p<0.01) in the number of eggs per gram of feces and coprocultures was foun...
Denwood MJ, Love S, Innocent GT, Matthews L, McKendrick IJ, Hillary N, Smith A, Reid SW.The faecal egg count (FEC) is the most widely used means of quantifying the nematode burden of horses, and is frequently used in clinical practice to inform treatment and prevention. The statistical process underlying the FEC is complex, comprising a Poisson counting error process for each sample, compounded with an underlying continuous distribution of means between samples. Being able to quantify the sources of variability contributing to this distribution of means is a necessary step towards providing estimates of statistical power for future FEC and FECRT studies, and may help to improve t...
Mshelia PW, Kappmeyer L, Johnson WC, Kudi CA, Oluyinka OO, Balogun EO, Richard EE, Onoja E, Sears KP, Ueti MW.Equine piroplasmosis (EP) is an infectious, tick-borne disease caused by the hemoprotozoan parasites, Theileria equi, Babesia caballi, and a recently reported new species, T. haneyi. Infections by these apicomplexan parasites limit performance and cause economic losses for the horse industry. Equine piroplasmosis is widespread in the northern regions of Nigeria, where an increasing portion of the animal population is composed of horses. This disease has remained epidemiologically challenging, especially as the movement of horses increases across Nigeria. In this study, blood samples from 300 h...
Slocombe JO, de Gannes RV, Lake MC.The aims of studies in 2002 and 2003 on three farms with 76 foals naturally infected with Parascaris equorum were to (i) identify if the nematode was resistant to ivermectin and moxidectin, and (ii) confirm the effectiveness of fenbendazole and pyrantel pamoate for the parasite. Twelve clinical trials, each with a Fecal Egg Count Reduction Test, were conducted on two Thoroughbred and one Standardbred farms in southwestern Ontario, Canada. In each trial, Parascaris eggs/g feces were estimated for each foal pre- and post-treatment using the Cornell-Wisconsin double flotation and Cornell-McMaster...
Kamran K, Ali A, Villagra C, Siddiqui S, Alouffi AS, Iqbal A.Zoonotic diseases are significant public health issues. There is an urgent need to focus our efforts on the development of strategies that prevent and control potential arthropod vector-borne pathogens. Hard ticks transmit a variety of viral, bacterial and protozoan pathogens to their vertebrate hosts. This is becoming of more concern, as anthropogenic alterations of the environment may unleash the spread of tick-borne diseases throughout the world. Developing countries that are highly dependent on the livestock economy are a hot spot for tick-borne infectious diseases. In this work, through a...
Bredtmann CM, Krücken J, Murugaiyan J, Kuzmina T, von Samson-Himmelstjerna G.Human and animal health is globally affected by a variety of parasitic helminths. The impact of co-infections and development of anthelmintic resistance requires improved diagnostic tools, especially for parasitic nematodes e.g., to identify resistant species or attribute pathological effects to individual species or particular species combinations. In horses, co-infection with cyathostomins is rather a rule than an exception with typically 5 to 15 species (out of more than 40 described) per individual host. In cyathostomins, reliable morphological species differentiation is currently limited ...
Bosco A, Maurelli MP, Ianniello D, Morgoglione ME, Amadesi A, Coles GC, Cringoli G, Rinaldi L.Nematode infections in horses are widespread across the world. Increasing levels of anthelmintic resistance, reported worldwide in equine parasites, have led to the creation of programs for the control of nematodes based on faecal egg counts (FEC). To improve nematode egg counting in equine faecal samples and establish whether the matrix of equine faeces or the eggs affect the counts, the analytical sensitivity, accuracy and precision of Mini-FLOTAC (combined with Fill-FLOTAC), McMaster and Cornell-Wisconsin techniques were compared. Known numbers of eggs extracted from equine or ovine faeces ...
Gerhard AP, Krücken J, Heitlinger E, Janssen IJI, Basiaga M, Kornaś S, Beier C, Nielsen MK, Davis RE, Wang J, von Samson-Himmelstjerna G.P-glycoproteins (Pgp) have been proposed as contributors to the widespread macrocyclic lactone (ML) resistance in several nematode species including a major pathogen of foals, Parascaris univalens. Using new and available RNA-seq data, ten different genomic loci encoding Pgps were identified and characterized by transcriptome-guided RT-PCRs and Sanger sequencing. Phylogenetic analysis revealed an ascarid-specific Pgp lineage, Pgp-18, as well as two paralogues of Pgp-11 and Pgp-16. Comparative gene expression analyses in P. univalens and Caenorhabditis elegans show that the intestine is the maj...
Fritzen B, Rohn K, Schnieder T, von Samson-Himmelstjerna G.Increasing prevalence of anthelmintic resistance in equine nematodes calls for a reexamination of current parasite control programmes to identify factors influencing control efficacy and development of resistance. Objective: To investigate if associations occur between prevalence of parasitic nematodes and management practices. Methods: German horse farms (n = 76) were investigated in 2003 and 2004. Information on farm and pasture management with respect to endoparasite control measures obtained using a questionnaire survey. Faecal examinations were performed in parallel. Results: Horses (n = ...
Angulo-Valadez CE, Scholl PJ, Cepeda-Palacios R, Jacquiet P, Dorchies P.Larvae causing obligatory myiasis are numerous and they may affect cutaneous and subcutaneous tissues, wounds, nasopharyngeal cavities (nasal bots), internal organs and the digestive tract (bots) of domestic and wild animals and humans as well. Nasal bots belong to the Family Oestridae, Subfamily Oestrinae, which includes several important genera: Oestrus, Kirkioestrus, and Gedoelstia infecting Artiodactyla (except Cervidae) in Africa and Eurasia, Cephenemyia and Pharyngomyia infecting Cervidae, Rhinoestrus infecting horses, Cephalopina infecting camels, Pharyngobolus infecting African elephan...
Linklater WL, Cameron EZ.Breeding groups with multiple stallions occur sympatrically with single-stallion breeding groups in feral horse, Equus caballus, populations. Mutualism and reciprocal altruism between stallions have been proposed to explain the origin and functioning of multistallion bands. However, empirical support for these hypotheses is contradictory and incomplete. Furthermore, there are no explicit tests of the predictions that each hypothesis makes about stallion behaviour and social structure. We compared nine multistallion and 18 single-stallion bands in the Kaimanawa Ranges, New Zealand. Compared wit...
Montes Cortés MG, Fernández-García JL, Habela Martínez-Estéllez MÁ.Equine piroplasmoses are enzootic parasitic diseases distributed worldwide with high incidence in tropical and subtropical regions. In Spain, there is insufficient epidemiological data about equine piroplasmoses. The main aim of the present study was therefore to estimate the prevalence of Theileria equi and Babesia caballi in five regions and obtain information about the risk factors. This study was conducted in the central and south-western regions of Spain, using indirect fluorescence antibody testing (IFAT) in 3,100 sera samples from apparently healthy horses of different ages, breeds, coa...
Lun ZR, Fang Y, Wang CJ, Brun R.Trypanosomiasis caused by Trypanosoma evansi (surra) is a problem of great economic importance in livestock in China because it affects important working animals: buffaloes in the south and east, and horses and cattle in the north and west. In addition, buffaloes are an important source of meat and leather for the Chinese population. In the north and west, T. evansi is found mainly in camels, whereas in the east, the south and the southwest, it is primarily buffaloes, cattle and horses that are affected by this parasitic flagellate. Although trypanosomiasis is one of the most important parasit...
Boersema JH, Eysker M, Maas J, van der Aar WM.The reappearance of strongyle eggs in faeces after treatment with ivermectin or pyrantel embonate was investigated in 22 foals, 36 yearlings, and 45 adult horses on five Dutch horse farms. The results confirmed earlier studies which showed an egg reappearance period of 9 and 6 weeks after ivermectin and pyrantel treatment, respectively. There were no differences between the egg reappearance periods of foals, yearlings, and adult horses. The mean egg counts of the yearlings were, however, consistently higher than the mean egg counts of the adult horses and foals in both ivermectin- and pyrantel...
Vieira RF, Vidotto O, Vieira TS, Guimaraes AM, Santos AP, Nascimento NC, Santos NJ, Martins TF, Labruna MB, Marcondes M, Biondo AW, Messick JB.The aims of this study were to determine the prevalence of hemoplasmas in a rural Brazilian settlement's population of human beings, their dogs and horses, highly exposed to tick bites; to identify the tick species parasitizing dogs and horses, and analyze factors associated with their infection. Blood samples from 132 dogs, 16 horses and 100 humans were screened using a pan-hemoplasma SYBR green real-time PCR assay followed by a species-specific TaqMan real-time PCR. A total of 59/132 (44.7%) dog samples were positive for hemoplasmas (21 Mycoplasma haemocanis alone, 12 ' Candidatus Mycoplasma...
Traversa D, Giangaspero A, Iorio R, Otranto D, Paoletti B, Gasser RB.Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) are parasitic nematodes which infect the stomach and/or skin of equids. The accurate diagnosis of gastric habronemosis is central to studying its epidemiology, but data on its distribution and prevalence are lacking, mainly due to the limitations of clinical and coprological diagnosis in live horses. To overcome this constraint, a two-step, semi-nested PCR-based assay was validated (utilizing genetic markers in the nuclear ribosomal DNA) for the specific amplification of H. microstoma or H. muscae DNA from the faeces from ho...
Lind EO, Rautalinko E, Uggla A, Waller PJ, Morrison DA, Höglund J.Virtually all horses are infected with helminth parasites. For some decades, the control of parasites of Swedish horses has been based on routine treatments with anthelmintics, often several times per year. Since anthelmintic resistance is becoming an increasing problem it is essential to develop more sustainable control strategies, which are adapted to different types of horse management. The aim of this study was to obtain information on practices used by Swedish horse owners for the control of endoparasites. Methods: A questionnaire with 26 questions about management practices and parasite ...
Hedrick PW, Parker KM, Miller EL, Miller PS.The major histocompatibility complex (MHC) is a fundamental part of the vertebrate immune system, and the high variability in many MHC genes is thought to play an essential role in recognition of parasites. The Przewalski's horse is extinct in the wild and all the living individuals descend from 13 founders, most of whom were captured around the turn of the century. One of the primary genetic concerns in endangered species is whether they have ample adaptive variation to respond to novel selective factors. In examining 14 Przewalski's horses that are broadly representative of the living animal...
Nielsen MK.The first parasite fecal egg counting techniques were described over 100 years ago, and fecal egg counting remains essential in parasitology research as well as in clinical practice today. Several novel techniques have been introduced and validated in recent years, but this work has also highlighted several current issues in this research field. There is a lack of consensus on which diagnostic parameters to evaluate and how to properly design studies doing so. Furthermore, there is a confusing and sometimes incorrect use of terminology describing performance of fecal egg counting techniques, a...
Lyons ET, Swerczek TW, Tolliver SC, Bair HD, Drudge JH, Ennis LE.A survey to determine current prevalence of several species of endoparasites in equids (n=350) at necropsy was conducted at the Livestock Disease Diagnostic Center in central Kentucky (1995-1999). Thelazia lacrymalis were found in 42% of the 1- to 4-year olds (n=132), which was the only age group examined for these parasites. Five- to 30-year olds (n=157), examined for Onchocerca spp. worms/lesions, had a prevalence of 24%. In > or =1-year olds (n=324), the infection rate for Gasterophilus intestinalis was 12% for second instars and 14% for third instars and for Gasterophilus nasalis was 2%...
Anderson RC, Linder KE, Peregrine AS.Although the original description given by Stefanski (1954) was satisfactory, Anderson & Bemrick (1965), in describing H. deletrix (= Micronema deletrix), claimed Stefanski's description was "inadequate" and the species a "species inquirenda". Thus, infections in horses and humans have been assigned to H. deletrix. We believe the species reported in horses and humans is H. gingivalis and that H. deletrix is its synonym. H. gingivalis is separated herein from forms found free-living. The genital tract in the advanced fourth stage of H. gingivalis is didelphic and amphidelphic and terminal e...
Dias Fde O, Lorosa ES, Rebêlo JM.A precipitin test was employed to study the alimentary tract content of Lutzomyia longipalpis in the intra- and peridomiciliary environments in the municipality of Raposa, Maranh o State, a transmission area for visceral leishmaniasis or kala azar. Out of 2,240 female sandflies captured, 547 (24.4%) had fed on vertebrate blood, with the following proportions: avian (87.9%); rodent (47.2%); human (42.4%); canine (27.6%); opossum (26.6%); and equine (22.5%). Based on a survey of 120 human dwellings, chickens were found to be the most common domestic animals in the peridomicile (28.3%), followed ...
