Anoplocephala Perfoliata Research Articles

Performance of three techniques for diagnosing equine tapeworm infection

Tapeworm infection in horses can cause serious health concerns, and recent data have documented treatment failures in the most common species, Anoplocephala perfoliata. The threat of anthelmintic resistance in A. perfoliata is of particular concern because of poor diagnostic performance of standard egg counting techniques for detecting this parasite. This study compared the performance of three diagnostic techniques 1) Mini-FLOTAC, 2) Cornell-Wisconsin, and 3) Proudman and Edwards used to detect and quantify A. perfoliata eggs in naturally infected horses. Eighteen adult female horses from the University of Kentucky’s historic parasitology herd were included in this study. Fecal samples were collected from all horses at five collection time points two weeks apart and analyzed with the three techniques. A total of 90 samples were collected and 270 counts determined in the study. The proportions of positive samples determined by the three techniques were significantly different from each other (p<0.05): Mini-FLOTAC (16%), Cornell-Wisconsin (47%), and Proudman and Edwards (70%). The Proudman and Edwards technique counted consistently higher numbers of tapeworm eggs compared to the other two techniques throughout the study [p < 0.05]. Total raw counts of tapeworm eggs across the study for each technique were 16, 88, and 410 for the Mini-FLOTAC, Cornell-Wisconsin, and Proudman and Edwards, respectively. This study demonstrated that the Proudman and Edwards technique was superior in diagnosing A. perfoliata infection. Future work needs to assess this technique’s potential for Fecal Egg Count Reduction Testing (FECRT).

DNA barcoding of Anoplocephala perfoliata derived from a draft horse (Ban'ei horse) in Hokkaido, Japan.

A two-year-old male Japanese draft horse (known as a "Ban'ei horse") excreted eight cestodes. Based on their morphological features, they were identified as Anoplocephala perfoliata. The partial mitochondrial cytochrome c oxidase subunit 1 (COI) sequences of the worms were nearly identical to A. perfoliata isolated from horses in Europe. The results of phylogenetic analyses of COI revealed that our samples and the European isolates formed the same clade, which was separate from Chinese and Australian isolates. Ban'ei horses were developed by crossbreeding draft horses imported from European countries in the 1900s. Our results suggest that A. perfoliata was transported to Hokkaido with horses from Europe. To our knowledge, this is the first report of A. perfoliata infection in a Japanese draft horse.

The Use of Innovative Diagnostics to Inform Sustainable Control of Equine Helminth Infections.

Helminths are commonly found in grazing equids, with cyathostomin nematodes and the cestode Anoplocephala perfoliata being the most prevalent. Most horses harbour low burdens of these parasites and do not develop signs of infection; however, in a small number of animals, high burdens can accumulate and cause disease. Cyathostomins are associated with a syndrome known as larval cyathostominosis. This occurs when large numbers of larvae emerge from the large intestinal wall. This disease has a case fatality rate of up to 50%. A. perfoliata infection has been associated with various types of colic, with burdens of >20 worms associated with pathogenicity. Anthelmintic resistance is a serious problem in cyathostomins and is emerging in A. perfoliata. Control methods that reduce reliance on anthelmintics now need to be applied, especially as no new dewormer compounds are on the horizon. Sustainable control methods must employ diagnostics to identify horses that require treatment. Coprological tests (faecal egg counts, FECs) have been used for several decades to inform treatment decisions to reduce helminth egg shedding. These tests cannot be used to assess host burdens as FECs do not correlate with cyathostomin or A. perfoliata burdens. In the last decade, new tests have become available that measure parasite-specific antibodies, the levels of which have been shown to correlate with parasite burden. These tests measure antigen-specific IgG(T) and are available in serum (cyathostomin, A. perfoliata) or saliva (A. perfoliata) formats. Tests for other helminths have been developed as research tools and need to be translated to support equine clinicians in practice. A key element of sustainable control strategies is that diagnostics must be used in combination with management approaches to reduce environmental transmission of helminths; this will help limit the proportion of horses harbouring parasite burdens that need to be targeted by treatment. This manuscript provides a review of the development, performance and general utility of various diagnostic methods for informing equine helminth management decisions.

Apparent treatment failure of praziquantel and pyrantel pamoate against anoplocephalid tapeworms

Anoplocephalid tapeworms are commonly occurring in grazing horses around the world. Two currently available anthelmintics have documented high efficacy against Anoplocephala perfoliata; praziquantel in various dosages ranging from 1.0 to 2.5 mg/kg and pyrantel pamoate administered at 13.2 mg base/kg. Anthelmintic resistance has not been reported in A. perfoliata, but anecdotal reports made during 2022 have suggested a possible loss of efficacy for both actives. This paper reports fecal egg count data from a Thoroughbred operation in Central Kentucky in 2023. Fifty-six yearlings were first dewormed with a combination of ivermectin (200 μg/kg) and praziquantel (1.5 mg/kg) and subsequently treated with pyrantel pamoate (13.2 mg base/kg). Fecal egg counts were determined at the day of treatment and again 14 days post-treatment. Two groups of mares (n = 39 and 45) were also treated with ivermectin/praziquantel and examined pre- and post-treatment. Low efficacy of ivermectin and pyrantel pamoate was demonstrated against strongylid parasites in the yearlings with mean Fecal Egg Count Reductions (FECRs) at 75.6% or below and upper 95% credible interval (CI) limits below 90% in all cases. Overall anti-cestodal FECR levels in the yearlings were 23.5% (95% CI: 11.2–48.0) for praziquantel and 50.9% (20.5–72.0) for pyrantel pamoate. Praziquantel eliminated anoplocephalid eggs from three of 17 yearlings, but another 5 yearlings went from negative to positive status following treatment. Pyrantel pamoate failed to eliminate anoplocephalid eggs from any of 14 treated tapeworm-positive yearlings. Nine of 84 mares tested positive for anoplocephalid eggs, and seven of these were still positive post praziquantel treatment. These findings sharply contrast data from historic field efficacy studies conducted for both actives and raise concern about anthelmintic resistance having possibly developed. This emphasizes the need for developing and refining antemortem methodologies for evaluating anti-cestodal treatment efficacy and for searching for possible alternative treatment options.

Prevalence and risk factors associated with donkey gastrointestinal parasites in Shashemane and Suburbs, Oromia Region, Ethiopia

BackgroundGastrointestinal parasites are the cause of morbidity and mortality in working donkeys and reduce their working performance. MethodsA cross-sectional study was conducted from November 2020 to July 2021 to assess gastrointestinal parasite infection in working donkeys in Shashemane and the surrounding district. A total of 395 donkeys were randomly sampled for the study, and an examination was conducted using faecal egg count and the Baermann technique. ResultsOut of the 395 sampled donkeys, different types of gastrointestinal parasites were identified. The parasites identified during the study were Strongyle spp. (100%), Oxyuris equi (10.1%), Parascaris equorum (23.8%), Fasciola spp. (0.3%), Gastrodiscus aegyptiacus (4.6%), Strongyloides westeri (47.8%) and Anoplocephala perfoliata (0.5%). Identification of L3 larvae of GI parasites revealed that Cyathostomes spp. (96.2%), Strongylus vulgaris (92.9%), Trichostrongylus axei (90.4%), Strongylus edentatus (89.4%), and Dictyocaulus arnifieldi (49.6%) were the most prevalent. Infection with one species of helminth was more common (60.8%). ConclusionsThus, working donkeys in the present study area were infected with Strongyle spp. (100%), Strongyloides westeri (47.8%), Parascaris equorum (23.8%), Oxyuris equi (10.1%), Gastrodiscus aegyptiacus (4.6%), Anoplocephala perfoliata (0.5%) and Fasciola spp. (0.3%) parasites. Hence, comprehensive donkey health, management, and implementation of appropriate parasite control strategies should be implemented to alleviate these problems.

Label-free quantitative proteomics and immunoblotting identifies immunoreactive and other excretory-secretory (E/S) proteins of Anoplocephala perfoliata.

Anoplocephala perfoliata is a common tapeworm in horses causing colic and even mortalities. Current diagnostic tests to detect A. perfoliata infections have their limitations and an improved method is needed. Immunoreactive excretory/secretory proteins (E/S proteome) of this parasite can provide promising candidates for diagnostic tests. We compared E/S proteins produced by small (length < 20mm, width < 5mm) and large (length 20 to 40mm, width 5 to 10mm) A. perfoliata worms in vitro by label-free quantitative proteomics using a database composed of related Hymenolepis diminuta, Echinococcus multilocularis/granulosus and Taenia aseatica proteins for protein identifications. Altogether, 509 E/S proteins were identified after incubating the worms in vitro for three and eight hours. The greatest E/S proteome changes suggested both worm size- and time-dependent changes in cytoskeleton remodeling, apoptosis, and production of antigens/immunogens. The E/S proteins collected at the three-hour time point represented the natural conditions better than those collected at the eight-hour time point, and thereby contained the most relevant diagnostic targets. Immunoblotting using antibodies from horses tested positive/negative for A. perfoliata indicated strongest antigenicity/immunogenicity with 13-, 30- and 100-kDa proteins, involving a thioredoxin, heat-shock chaperone 90 (Hsp90), dynein light chain component (DYNLL), tubulin-specific chaperone A (TBCA) and signaling pathway modulators (14-3-3 and Sj-Ts4). This is among the first studies identifying new diagnostic targets and A. perfoliata antigens eliciting a IgG-response in horses.

Disease surveillance in England and Wales, June 2022.

Disease surveillance in England and Wales, June 2022.

DISTRIBUTION AND SEASONAL DYNAMICS OF ANOPLOCEPHALIDOSIS OF HORSES IN THE CONDITIONS OF THE CENTRAL ALTAI

The purpose of the work was to assess the invasiveness and determine the features of the seasonal dynamics of equine anoplocephalidosis in the conditions of the Central Altai. The studies were carried out in 13 farms of 5 administrative districts of the physico-geographical province. Fecal samples were examined by methods generally accepted in parasitology. Identification of the cestodes was carried out taking into account the size and morphological features of the eggs, including the pear-shaped apparatus. Three species of cestodes from the family of the Anoplocephalidae have been recorded: Anoplocephala perfoliata, Anoplocephala magna and Paranoplocephala mamillana. In the vast majority of cases, A. perfoliata eggs were isolated in fecal samples, propagative forms of the remaining cestodes were sporadically encountered. According to the results of the conducted studies, it was found that anoplocephalidosis are ubiquitous with significant fluctuations in EI indicators in the context of administrative districts. The maximum infection of animals with pathogens of these cestodosis was detected in the Chemalsky district – 23.8%, which is almost 2.5–3 times higher than in the Shebalinsky (9.8%) and Ongudaysky (8.8%) districts. The average incidence of horses with anoplocephalidosis was recorded in the Ust-Kansky and Ust-Koksinsky districts – 12.8 and 11.5%, respectively. Seasonal dynamics of anoplocephalidoses is characterized by a single-peak rise of invasion in the summer – autumn period with maximum EI in September – 34.4%.

Anoplocephala perfoliata

This datasheet on Anoplocephala perfoliata covers Identity, Distribution, Hosts/Species Affected.

Evidence of Immune Modulators in the Secretome of the Equine Tapeworm Anoplocephala perfoliata.

Anoplocephala perfoliata is a neglected gastro-intestinal tapeworm, commonly infecting horses worldwide. Molecular investigation of A. perfoliata is hampered by a lack of tools to better understand the host–parasite interface. This interface is likely influenced by parasite derived immune modulators released in the secretome as free proteins or components of extracellular vesicles (EVs). Therefore, adult RNA was sequenced and de novo assembled to generate the first A. perfoliata transcriptome. In addition, excretory secretory products (ESP) from adult A. perfoliata were collected and EVs isolated using size exclusion chromatography, prior to proteomic analysis of the EVs, the EV surface and EV depleted ESP. Transcriptome analysis revealed 454 sequences homologous to known helminth immune modulators including two novel Sigma class GSTs, five α-HSP90s, and three α-enolases with isoforms of all three observed within the proteomic analysis of the secretome. Furthermore, secretome proteomics identified common helminth proteins across each sample with known EV markers, such as annexins and tetraspanins, observed in EV fractions. Importantly, 49 of the 454 putative immune modulators were identified across the secretome proteomics contained within and on the surface of EVs in addition to those identified in free ESP. This work provides the molecular tools for A. perfoliata to reveal key players in the host–parasite interaction within the horse host.

Associative parasitoses of the gastrointestinal tract of horses and assessment of anti-parasitic drugs efficiency

Invasive diseases of horses are an urgent problem in the horse breeding industry of the Republic of Belarus, as well as in the near and far abroad countries. The main role among the parasitic pathology is occupied by helminths of the small and large intestine, as well as larvae of gasterophilus. In associative course, they are the cause of significant economic losses associated with the growth and development of sick young animals, reduced performance, endurance of animals, increased susceptibility to other diseases, and even the death of animals. Planned therapeutic and preventive measures using broad-spectrum anthelmintics is a priority measure to reduce economic damage in development of the horse breeding industry. The paper provides data on spread of parasitoses of gastrointestinal tract in horses in the Republic of Belarus during period of 2004-2020. The paper presents the species composition of horse parasites localized in the stomach, small and large intestines. Data on extensiveness and intensity of invasions of horses by parasitocenosis of digestive tract in terms of age are presented. Therapeutic efficiency of antiparasitic drugs of various pharmacological groups in mono- and polyinfestations of gastrointestinal tract of horses are studied. High extensibility of Avermectin series preparations (Avermectin paste 1 %, Rivertin 1 %) has been determined for nematodes of gastrointestinal tract of horses and gastrointestinal disease. High efficiency has been obtained from a new complex antiparasitic preparation for horses “Prazimax” in mono- and polyinfestations caused by parasites of gastrointestinal tract, including nematodes of the small and large intestines, larvae of gasterophilus and Anoplocephala perfoliata cestodes. Data on spread of associative course of parasitocenoses of the digestive tract of horses, age and seasonal dynamics will allow veterinary specialists to make timely diagnosis, conduct differential diagnostics, determine the optimal timing of diagnostic, therapeutic and preventive treatments, taking into account the specifics of parasitocenosis.

Prevalence of Gastrointestinal Helminthiasis in Horses and Donkeys of Hawassa District, Southern Ethiopia.

Background Gastrointestinal helminth parasite infection is a major influencing factor against the profitability of working equines all over the world. Methods A cross-sectional study was conducted to determine the prevalence of gastrointestinal tract (GI) helminths and assess the associated risk factors in donkeys and horses in the Hawassa district. A total of 214 fecal samples were collected from randomly selected equines (112 donkeys and 102 horses) and examined for the presence of eggs of GI helminths using standard coprological techniques. Results According to the current study, the prevalence of GI helminths in equine was 78.5% (168/214) and the highest prevalence was reported in donkeys 92% (103/112) as compared to horses 63% (65/102). Out of 168 positive samples, the different species of parasites were identified, namely, Strongyle species 120 (56.1%), Strongyloides westeri 76 (35.5%), Parascaris equorum 54 (25.2%), Anoplocephala perfoliata 34 (15.8%), Oxyuris equi 20 (9.3%), Fasciola hepatica 18 (8.8%), Gastrodiscus species 12 (5.6%), and Dictyocaulus arnfieldi 4 (1.8%). There was a strong association between the prevalence of GI helminths and factors such as the species of equine, body condition scores, and feed type (p < 0.05). However, no significant association (p > 0.05) was observed between the prevalence of GI helminths and putative risk factors such as age, sex, housing, and water source. The coproculture performed on 30 pooled fecal samples revealed that Cyathostomes species, Strongylus vulgaris, and Strongylus edentatus were the major helminth parasites of donkeys and horses. Conclusion The frequency of gastrointestinal helminths in equine species was high, especially in donkeys. Hence, strategic deworming using broad-spectrum antihelminthic drugs and a rotational grazing program should be implemented to control and prevent the diseases.

A Comparison of the Colonic Microbiome and Volatile Organic Compound Metabolome of Anoplocephala perfoliata Infected and Non-Infected Horses: A Pilot Study.

Simple SummaryIn horses, tapeworm infection is associated with specific forms of colic (abdominal pain) that can be life-threatening without surgical treatment. There is growing evidence that intestinal parasites interact with the gut bacteria, and the consequences of these interactions may influence the ability of the host to resist infection and parasite-associated disease. We aimed to compare the intestinal bacteria and the gases produced by metabolic processes in the gut between horses that had varying levels of tapeworms and those with no tapeworm present. Overall, the diversity of gut bacteria was similar in horses with and without tapeworms. There were some decreases in beneficial bacteria in horses with tapeworms, indicating a possible negative consequence of infection. Intestinal gases correlated with some bacteria indicating their functionality and use as potential markers of active bacteria. Our study validates further research investigating tapeworm and gut bacteria interactions in the horse.Anoplocephala perfoliata is a common equine tapeworm associated with an increased risk of colic (abdominal pain) in horses. Identification of parasite and intestinal microbiota interactions have consequences for understanding the mechanisms behind parasite-associated colic and potential new methods for parasite control. A. perfoliata was diagnosed by counting of worms in the caecum post-mortem. Bacterial DNA was extracted from colonic contents and sequenced targeting of the 16S rRNA gene (V4 region). The volatile organic compound (VOC) metabolome of colonic contents was characterised using gas chromatography mass spectrometry. Bacterial diversity (alpha and beta) was similar between tapeworm infected and non-infected controls. Some compositional differences were apparent with down-regulation of operational taxonomic units (OTUs) belonging to the symbiotic families of Ruminococcaceae and Lachnospiraceae in the tapeworm-infected group. Overall tapeworm burden accounted for 7–8% of variation in the VOC profile (permutational multivariate analysis of variance). Integration of bacterial OTUs and VOCs demonstrated moderate to strong correlations indicating the potential of VOCs as markers for bacterial OTUs in equine colonic contents. This study has shown potential differences in the intestinal microbiome and metabolome of A. perfoliata infected and non-infected horses. This pilot study did not control for extrinsic factors including diet, disease history and stage of infection.

Molecular identification of tapeworms from Konik Polski horses from Biebrza National Park.

Tapeworm infections in Konik Polski horses from Biebrza National Park were investigated in this study. Faecal samples were collected 10 times: in 2012 - 1 time, in 2013 - 4 times, in 2014 - 4 times and in 2015 - 1 time. In total, 162 faecal samples were collected and tested. Faecal egg counts (FECs) method was used in the study. Positive samples with cestode eggs were noted only twice - in October 2012 and December 2013 in two adult mares (9 and 11 years old). The determined prevalence was surprisingly low comparing to other studies, 4.3% in October 2013 and 28.5% in December 2013. Parasite genomic DNA was isolated from posterior proglottids of tapeworms found in horse faeces after deworming, PCR technique was applied in order to determine the species of these tapeworms. No specific products were obtained using primers specific to rDNA sequence, whereas, a 620 bp fragment encoding mitochondrial cytochrome oxidase I (COI) was amplified and sequenced. Nucleotide sequence analysis revealed a 100% homology to a corresponding fragment form Anoplocephala perfoliata tapeworm originating from a horse from the Czech Republic. To our knowledge this is the first report applying molecular techniques to tapeworm identification in Konik Polski horses.

Comparative Analysis of Intestinal Helminth Infections in Colic and Non-Colic Control Equine Patients.

Simple SummaryThe most important equine intestinal worm species include the roundworms Strongylus vulgaris and Parascaris spp. as well as tapeworms such as Anoplocephala perfoliata. These parasites reside in the small and large intestine and may cause various signs of disease, such as diarrhea, unthriftiness, or colic. However, following decades of routine anti-worm treatments, it is currently unclear what relevance these infections have in the context of colic under the prevailing situation. Therefore, we examined the signs of the presence of the infection concerning the above-mentioned parasites in 620 equine clinic patients, half of these admitted after being diseased with colic and the other admitted due to non-intestinal diseases. With approximately on third of all horses being positive for antibodies directed against S. vulgaris, we detected an unexpectedly high infection rate. With every tenth horse showing respective antibodies, also tapeworm infections were encountered in a considerable proportion of the examined horses. Somewhat unexpectedly, no association between worm infection and colic was detected. However, recent—i.e., during the last seven days—anthelmintic treatment was 2.4 times more often seen in horses showing signs of colic. Overall, the considerable S. vulgaris and tapeworm infection rates mean we should stay alert in continuing worm monitoring and control.All around the world, intestinal helminths constitute one of the most prevalent life-long occurring infections and re-infections affecting all horse age groups. A range of parasite species among strongyles, ascarids, and tapeworms is known to have the potential to cause colic in horses. However, there is a lack of current scientific evidence on the actual relevance of helminth infection levels in the context of colic in horses kept during prevailing epidemiological conditions. Thus, a prospective case-control study on the occurrence of intestinal helminths in a total of 620 mainly adult equine clinic patients was conducted to investigate the association between colic and helminth infection. For each horse, a range of copromicroscopic, serological, and clinical data was obtained, in addition to a questionnaire on relevant anamnestic data, including previous anthelmintic treatment and husbandry. Using a FLOTAC-based copromicroscopic diagnosis, the highest infection rates were seen for strongyles (41.8%), followed by Anoplocephala perfoliata and Parascaris spp. (both 0.8%), with no significant difference between the two study groups. Employing a real-time PCR a 1.1% S. vulgaris DNA prevalence was found. Considerably higher seroprevalences were observed using S. vulgaris and A. perfoliata ELISAs, with 32.3% and 10.7%, respectively. It was noteworthy that no association concerning either serologic status was encountered with colic status. The shedding of strongyle eggs was associated with a 1.8-times increased risk of S. vulgaris seropositivity. Recent anthelmintic treatment was associated with the onset of colic, as animals who had received an anthelmintic during the previous week had a 2.4-times higher risk of signs of colic compared to those who had been treated at least eight weeks prior. Another noteworthy observation was that ponies were significantly less often affected by colic than warmbloods. The high S. vulgaris and considerable A. perfoliata seroprevalences encountered in this investigation should prompt veterinarians, farm managers, and horse owners to maintain consequent and effective worm control measures.

Parasites in Horses Kept in A 2.5 Year-Round Grazing System in Nordic Conditions without Supplementary Feeding.

Simple SummaryGrazing horses year-round may be a means to increase biodiversity. In this study, parasite occurrence was documented on a monthly basis in 1- to 3-year-old Gotlandsruss stallions grazed year-round for 2.5 years. Horses became infected by several parasites and, when needed (>200 strongyle eggs/gram feces), horses were dewormed with the anthelmintic drug pyrantel, which has low or no ecotoxic impact on soil fauna. This strategy failed to control small strongyle occurrence. Horses excreted larger amounts of small strongyle eggs during summer–autumn than during the rest of the year, and the number of excreted eggs increased year-on-year. High small strongyle egg excretion did not seem to affect the body condition of the horses. Some horses were also infested with chewing louse, but did not scratch more than unaffected horses. We found that to keep egg excretion below 200, pyrantel was not sufficient and a substance known to be toxic to dung fauna and freshwater invertebrates had to be used on some occasions.Horse grazing can be favorable from a biological diversity perspective. This study documented the occurrence of endo- and ectoparasites and sought to reduce parasite egg excretion with the anthelmintic drug pyrantel in 12 Gotlandsruss stallions maintained in a year-round grazing system for 2.5 years. Feces samples were collected monthly and all horses were treated with pyrantel, the anthelmintic drug of choice in biological diversity preservation, at study population mean cyathostomin eggs per gram (EPG) of >200. The relationship between cyathostomin EPG and body condition was studied, as was horse behavioral response to Bovicola equi (chewing louse) infestation. Eggs of cyathostomins (small strongyles), Parascaris spp. (roundworm), Oxyuris equi (pinworm), Anoplocephala perfoliata (tapeworm), and Gasterophilus spp. (botfly) were detected at least once during the trial. Excretion of cyathostomin eggs was highest during summer–autumn and increased year-on-year. No relationship was found between cyathostomin EPG and body condition. Infestation with B. equi did not affect the number of scratching sessions compared with unaffected horses. Therefore, in this year-round grazing system, pyrantel treatment had to be complemented with moxidectin to reduce excretion of cyathostomin eggs, thus compromising biological diversity.

Analysis of caecal mucosal inflammation and immune modulation during Anoplocephala perfoliata infection of horses.

Anoplocephala perfoliata is the commonest equine tapeworm, theadult parasites are attached in groups close to the ileocaecal valve causing marked inflammatory pathology. This work aimed to characterize the nature of the in vivo mucosal immune response to Aperfoliata, and to investigate the role of Aperfoliata excretory-secretory components in modulating in vitro immune responses. Real-time PCR detected elevation of IL13 and TGFβ transcription in early-stage Aperfoliata infection. In late-stage infection, IL-13, IL4 and Ifn transcripts were reduced while the regulatory cytokines, TGFβ, IL10 and the transcription factor FOXP3 were increased in tissue close to the site of Aperfoliata attachment; indicating downregulation of T-cell responses to Aperfoliata. In vitro, Aperfoliata excretory-secretory products induced apoptosis of the Jurkat T-cell line and premature cell death of ConA stimulated equine peripheral blood leucocytes. Analysis of cytokine transcription patterns in the leucocyte cultures showed a marked inhibition of IL-1 and IL-2 suggesting that a lack of T-cell growth factor transcription underlies the mechanism of the induced equine T-cell death. These preliminary findings suggest Aperfoliata may have the ability to down-regulate host T-cell responses.

Pixel by pixel: real-time observation and quantification of passive flotation speeds of three common equine endoparasite egg types

The efficacy of anthelmintic treatments against populations of endoparasites infecting livestock throughout the world is decreasing. To mitigate this, the use of fecal egg counts is recommended to determine both the necessity, and to ensure the appropriate choice, of anthelmintic treatment. Traditionally, and in order to facilitate easier identification and/or enumeration, samples are analysed after separating eggs from other fecal particulates by exposing them to a solution with a density higher than that of the eggs, but lower than the remaining fecal contents. While many parasite egg flotation protocols exist, little is known about the characteristics of these eggs with respect to their movement through a flotation solution. In this study, we have demonstrated a novel method for the observation and quantification of microscopic (65–100 µm) objects as they experience unassisted flotation. This also represents, to our knowledge for the first time, that the flotation of parasite eggs has been observed and their movement characteristics quantified as they float through solution. Particle tracking and video analysis software were utilised to automatically detect and track the movement of individual eggs as they floated. Three 30 s videos and one 2 min video of each egg type were analysed. If the first 30 s of video were discounted, the differences in mean flotation speed among all videos was statistically significant between egg types (P = 0.0004). Strongyle type eggs (n = 201) moved the fastest with a mean 51.08 µm/s (95% confidence interval: 47.54–54.62). This was followed by Parascaris spp. (n = 131) and Anoplocephala perfoliata eggs (n = 322), with mean speeds of 44.43 µm/s (95% confidence interval: 39.47–49.4) and 31.11 µm/s (95% confidence interval: 29.6–32.61), respectively. This method for evaluating the mean speed of passive flotation may represent a first step towards further optimizing fecal egg flotation and be of interest to parasitologists and veterinary practitioners.

Anoplocephala perfoliata Infection in Horses in Iceland: Investigation of Associations between Intensity of Infection and Lesions

In Iceland, there is at least 1 horse for every 5 human inhabitants, mostly kept on uncultivated rangelands. Although the Icelandic horse is considered robust compared with other breeds, it is nevertheless susceptible to disease. Few studies have investigated the prevalence of intestinal parasites in horses in Iceland. The purpose of this study was to determine the prevalence of the tapeworm, Anoplocephala perfoliata, in horses in Iceland and to explore associations between intensity of infection and the severity of macroscopic pathological lesions in this population. In addition, the relationship between infection and geographical location in Iceland, horse age, and gender were investigated. The utility of a modified McMaster flotation method for identifying infected horses from fecal samples was also studied. The study sample consisted of 104 horses (aged 1-30 yr) slaughtered in 3 abattoirs in North and South Iceland during June and July 2016. The prevalence of A. perfoliata in the horses was 64.4%, with between 1-131 worms found in infected horses. The pathological changes in the horses associated with infection varied from mild (hyperemia in small areas) to severe (large ulcers and necrotic lesions coated with fibrin), and intensity of infection correlated with the size and type of pathological lesions in the intestines. No statistically significant associations between infection with A. perfoliata and geographical location, horse age, or horse gender were detected. The McMaster egg counting method used here was of very low sensitivity (7.4%) and was concluded to be inadequate for detection of A. perfoliata infection in horses. The prevalence of A. perfoliata in horses in Iceland in this study was found to be relatively high compared with results from many studies performed elsewhere in Europe. This may reflect the lack of treatment of horses in Iceland for this parasite, the environmental suitability for the intermediate mite host, and grazing management practices in Iceland. The high prevalence and association with pathology suggest that diagnosis of infection using a sensitive method, along with appropriate treatment, should be considered for horses in Iceland.

ECOLOGICAL AND BIOLOGICAL PECULIARITIES OF THE DEVELOPMENT OF ORIBATIDE TONGS - INTERMEDIATE FARMS ANOPLOCEPHALID TABULAR HORSES IN THE REPUBLIC OF SAHA (YAKUTIA)

In the article, data on the distribution of anoplodsefalidosis of horses are given. Anoplodsefalidozy horses are widely distributed in the northern and central zones of the Republic of Sakha (Yakutia). The species composition of these cestodes is represented by 3 species: Anoplocephala magna, Anoplocephala perfoliata and Paranoplocephala mamillana. Of the 10 species of oribatid ticks found in the pastures of six species, anoploccephalidae, Achheteria coleoptrata, Scheloribates latipes, Scheloribates laevigatus, Galumna obvia, Ceratosetoides cisalpinus, Testocepheus velatus have been registered as intermediate hosts. The highest reproductive activity of oribatids occurs in May-June, which contributes to the massive infection of horses. In laboratory conditions, at a temperature of 28̊C and a relative humidity of 70-80 %, cysticercoids in mites form in 35-40 days.