Gastrointestinal parasites of working donkeys of Ethiopia

Impaired efficacy of fenbendazole and ivermectin against intestinal nematodes in adult horses in Iran

This study aimed to evaluate the efficacy of fenbendazole and ivermectin on strongyles and Parascaris sp. infecting adult riding horses in three regions with different climates. During 2021 and 2022 fecal specimens were randomly collected from 483 horses older than three years in 31 equestrian clubs in Hamedan (n = 217), Yazd (n = 146) and Tabriz cities (n = 120). Eggs were counted by McMaster technique, and the strongyle larvae were identified using coproculture, PCR and sequencing. Horses with strongyles and Parascaris egg counts ≥150 were enrolled in fecal egg count reduction (FECR) examination following treatment with ivermectin or fenbendazole. In total, 26.5% of examined horses were positive with at least one parasite. Infection rates varied in three cities i.e., 25.8% in Hamedan, 28.8% in Yazd, 25% in Tabriz. Fifty-seven horses had FECR measured. FECR below <90% was observed for IVM-strongyle in two horses in Tabriz, for FBZ-strongyle in two horses in Tabriz and two horses in Hamedan, for IVM-Parascaris in one horse in all three cities, and for FBZ-Parascaris in one horse in Yazd. Furthermore, FECR 90-100% was observed in IVM-Parascaris and FBZ -Parascaris groups in Tabriz. Data herein presented demonstrate different degrees of resistance of strongyles and Parascaris infecting horses in Iran against both ivermectin and fenbendazole. Since non-principled use of anthelminthics is common among horse owners, urgency of test-and-treatment strategy should be educated and implemented by policy-making organizations. Evaluating efficacy of different anthelminthics and choosing the most effective treatment in each region is suggested.

Fasciola hepatica Infection in Horses in Three Governorates in Northern Egypt: Prevalence and Risk Factors

Fasciola hepatica is a trematode parasite that affects wide range of mammalian hosts including horses. There are no epidemiological data on fasciolosis in Egyptian horses. Hence, the present study aimed to evaluate the seroprevalence of F. hepatica in horses using ELISA as well as assess the associated risk factors for fasciolosis infection. A total of 400 sera samples of horses from three Egyptian governorates were examined. The overall seroprevalence rate in horses was 13% and the disease was more prevalent in Qalubia (14.17%) and Gharbia (16.67%) which are located at Nile Delta. The likelihood of having F. hepatica seropositivity was higher in mixed-breed animals and stallions (OR = 3.97, 95%CI: 1.10-14.28 and OR = 2.07, 95%CI: 1.09-3.93, respectively), and in older horses more than 10 years (OR = 5.69, 95% CI: 1.98-16.36). Horses were more likely to be seropositive with F. hepatica when kept in outdoor housing (OR= 1.53, 95%CI: 0.78-3), during autumn (OR = 3.80, 95%CI: 1.17-12.32) and in the presence of snails (OR = 2.72, 95%CI: 1.34-5.52). Therefore, the obtained data contributes to the understanding of the epidemiology of Fasciola species, assess in establishment of management programmes to reduce disease and public health risks.

Horse and donkey parasitology: differences and analogies for a correct diagnostic and management of major helminth infections

In June 2022, at the XXXII Conference of the Italian Society of Parasitology, the parallels of the main endoparasitic infections of horses and donkeys were discussed. Although these 2 species are genetically different, they can be challenged by a similar range of parasites (i.e. small and large strongyles, and Parascaris spp.). Although equids can demonstrate some level of resilience to parasites, they have quite distinct helminth biodiversity, distribution and intensity among different geographical locations and breeds. Heavily infected donkeys may show fewer clinical signs than horses. Although parasite control is primarily provided to horses, we consider that there may be a risk of drug-resistance parasitic infection through passive infection in donkeys when sharing the same pasture areas. Knowing the possible lack of drug efficacy (<90 or 80%), it is advocated the use of selective treatment for both species based on fecal egg counts. Adult horses should receive treatment when the threshold exceeds 200–500 eggs per gram (EPG) of small strongyles. Moreover, considering that there are no precise indications in donkeys, a value >300 EPG may be a safe recommendation. We have highlighted the main points of the discussion including the dynamics of helminth infections between the 2 species.

A systematic review and meta-analysis of the prevalence of parasitic infections in equids in Ethiopia

We performed this review to determine the weighted prevalence of equids parasitic infections in Ethiopia. Article searches on parasites of equids were conducted using PubMed, PubMed Central, Google Scholar, Science Direct, Web of Sciences, Scopus, AJOLs and Research Gate. A random effects model was used to estimate the weighted prevalence and to study heterogeneity. The primary searches generated, 3082 potential studies, of which 66 reports met the inclusion criteria and were included in the meta-analysis. There were 32 reports involving two or more equids species, eighteen on donkeys, and sixteen on horses. Moreover, fifty of the reports mentioned helminth infections in equids, thirteen on protozoans, and three on ectoparasites. The estimated weighted prevalence of parasitic infections in equids was 58.3% (95% CI 50.8-65.4%, I2 = 99%). Helminths were the most prevalent parasites in equids, accounting for 77.1% (95% CI 71.4%, 82%, I2 = 98.5%), followed by ectoparasites at 35.4% (95% CI 33.4-37.52%, I2 = 88.2%) and haemoparasites (protozoans) at 10.84% (95% CI 6.6%, 17.3%, I2 = 98.1%). Furthermore, with a prevalence of 82.3% (95% CI 75.9-87.3%, I2 = 97.4%), donkeys were the most affected equids with helminth parasites. From the reports, we found forty-three species of helminth parasites affecting equids, including thirty-four nematode species (Strongylus, Cyathostomum, Coronocyclus, Cylicocyclus, Cylicostephanus, Trichostrongylus, Oesophagodontus, Strongyloides, Triodontophorus, Gyalocephalus, Poteriostomum, Dictyocaulus, Oxyuris, Habronema, Draschia, Parascaris, Setaria, and Probstmayria species), three trematodes (two Fasciola and one Gastrodiscus species), three cestodes (two Anoplocephala and one Anoplocephaloides species) and three botfly larvae (one Rhinoestrus and two Gasterophilus species). Trypanosoma species (T. congolense, T. vivax, T. brucei, T. equiperdum, and T. evansi), piroplasms (Theileria equi and Babesia caballi), and Eimeria species have also been reported to affect equids. Ticks (Amblyomma variegatum, A. gemma, Rhipicephalus decoloratus, R. evertisi evertisi, R. pulchellus, R. muhsame, R. sanguineus, Hyalomma rufipes, and Hy. truncatum) and lice (Bovicola equi and Haematopinus asini) were the ectoparasites recorded to affect equids. The risk of publication bias across studies was likely to be high due to differences in publication year and diagnostic techniques. In conclusion, parasitic infections of equids are common in Ethiopia and are caused by a variety of parasite species, putting the performance and well-being of these packing animals at risk. Therefore, more research is needed to identify infection risk factors and raise awareness of the consequences of parasitism in order to provide strategies to mitigate the problems in equids.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12639-023-01598-3.

Study on gastrointestinal nematode parasite infections of donkey in and around shone town, Hadiya zone, Southern Ethiopia

One of the most common factors limiting donkey health and productivity is infection with gastrointestinal nematode parasites. From December 2021 to May 2022, a cross-sectional study was conducted in and around Shone town, Hadiya zone, southern Ethiopia, to estimate the prevalence of donkey GIT nematode parasite infection and to assess its associated risk factors. For the coprological examination, 384 simple randomly selected donkeys were sampled from four peasant associations. To identify parasitic eggs in feces, the standard flotation technique was used. In the donkeys examined, the overall prevalence of gastrointestinal nematodes was 75.26% Strongyles (48.17%), Parascaris equorum (11.45%), Strongyloides (5.99%), and mixed infection (Strongyles + Parascaris (9.11%) and Strongyles + Strongyloides (0.52%)) were the most commonly encountered nematodes. There was also a statistically significant difference in the prevalence of donkey gastrointestinal parasites by sex, body condition, and management system (p < 0.05). Donkeys with semi-intensified (OR = 8.99) and poor body condition (OR = 6.48) were at an increased risk of infection compared to intensive management and good body condition. In conclusion, the current study demonstrated that gastrointestinal nematodes are the major health challenges for donkeys in the study area. As a result, strategic regular deworming, improved housing, and feeding management were recommended to improve the health and productivity of donkeys in the study area.

Awareness and control measures for gastrointestinal parasites in donkeys in Maseru district, Lesotho

Parasitic infection is one of the major problems in equines which negatively influence their health. It hinders working performance of equines. This study was conducted to evaluate donkey owners' knowledge and control measures on prevalence of gastrointestinal parasites (GIPs) in three agro-ecological zones (AEZs) of Maseru district. A total of 144 donkey owners were selected for individual interviews through a stratified random sampling. Descriptive statistics and chi-square tests were used to analyze data. The significance (p <0.05) of different AEZs was tested using a post-hoc cell-wise adjusted standardized residual analysis. Majority of donkey owners were familiar with the GIPs especially nematodes as it seemed to be the most occurring, but there was no significant effect (p > 0.05) across the AEZs. The adult donkeys were mostly susceptible to different GIPs according to respondents and severe infection was experienced in summer and winter. Donkeys were dewormed seasonally using anthelmintics with inappropriate weighing instruments to establish the dosage, however, chi-square test pointed out the significance (p = 0.004) effect between types of medication used across the AEZs. Donkeys were kept in non-roofed stables that were not cleaned regularly hence, these compromised their welfare. However, communal grazing shared by different livestock species was the main source of animal feeding though it was found to be the major source of GIPs. Therefore, there is a need to equip them on the proper skills to improve on their management practices and the behaviour of parasites in different areas. This will help donkey owners adhere to appropriate control and prevention strategies.

Developmental dynamics and survival characteristics of the common horse bot flies (Diptera, Gasterophilidae, Gasterophilus) in desert steppe

The genus Gasterophilus (Diptera, Gastrophilidae) is an obligate parasite of the equine family that causes widespread myiasis in desert steppe. Based on four common naturally excreted Gasterophilus larvae collected systematically in the Karamaili Ungulate Nature Reserve from March to September 2021, this paper studies the population dynamics and ontogenetic laws of horse flies, and discuss the coexistence pattern and population dynamics prediction of horse flies. The results showed that the Gasterophilus larvae had obvious concentrated development period, and the time of population peaks was different, the earliest was G. nigricornis (late March), followed by G. pecorum-Ⅰ (mid-April), G. nasalis (late April), G. intestinalis (early May), G. pecorum-Ⅱ (mid-August). The order of development threshold temperature "C_nigricornis < C_pecorum-Ⅰ ≤ C_pecorum-Ⅱ < C_nasalis < C_intestinalis" is consistent with the peak order of different larval populations. The life history survival rate (L) was as follows: L_nigricornis (83.97%) ≥ L_intestinalis (81.25%) > L_nasalis (72.42%) ≥ L_pecorum-Ⅱ (71.65%) > L_pecorum-Ⅰ (39.23%). This study combined indoor experiments and field surveys revealed the development of horse fly populations with different life strategies in desert grasslands. Based on the different development threshold temperatures of several horse flies, the staggered population dynamics of Gasterophilus form continuous infection stress on the host. In addition, G. pecorum exhibited a univoltine bimodal population distribution in this area and led to two high-intensity host infections, which is one of the important reasons why it has become the dominant species of myiasis in desert steppe.

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

Background

Gastrointestinal parasites are the cause of morbidity and mortality in working donkeys and reduce their working performance.

Methods

A 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.

Results

Out 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%).

Conclusions

Thus, 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.

Potential Hybridization of Fasciola hepatica and F. gigantica in Africa-A Scoping Review

The occurrence of Fasciola gigantica and F. hepatica in Africa is well documented; however, unlike in Asia, there is a paucity of information on the existence of hybrids or parthenogenetic species on the continent. Nonetheless, these hybrid species may have beneficial characteristics, such as increased host range and pathogenicity. This study provides evidence of the potential existence of Fasciola hybrids in Africa. A literature search of articles published between 1980 and 2022 was conducted in PubMed, Google Scholar, and Science Direct using a combination of search terms and Boolean operators. Fasciola species were documented in 26 African countries with F. hepatica being restricted to 12 countries, whilst F. gigantica occurred in 24 countries, identified based on morphological features of adult Fasciola specimens or eggs and molecular techniques. The co-occurrence of both species was reported in 11 countries. However, the occurrence of potential Fasciola hybrids was only confirmed in Egypt and Chad but is suspected in South Africa and Zimbabwe. These were identified based on liver fluke morphometrics, assessment of the sperms in the seminal vesicle, and molecular techniques. The occurrence of intermediate host snails Galba truncatula and Radix natalensis was reported in Ethiopia, Egypt, South Africa, Tanzania, and Uganda, where F. hepatica and F. gigantica co-occurrences were reported. The invasive Pseudosuccinea columella snails naturally infected with F. gigantica were documented in South Africa and Egypt. In Zimbabwe, P. columella was infected with a presumed parthenogenetic Fasciola. This suggests that the invasive species might also be contributing to the overlapping distributions of the two Fasciola species since it can transmit both species. Notwithstanding the limited studies in Africa, the potential existence of Fasciola hybrids in Africa is real and might mimic scenarios in Asia, where parthenogenetic Fasciola exist in most Asian countries. In South Africa, aspermic F. hepatica and Fasciola sp. have been reported already, and Fasciola hybrids have been reported? in Chad and Egypt. Thus, the authors recommend future surveys using molecular markers recommended to identify Fasciola spp. and their snail intermediate hosts to demarcate areas of overlapping distribution where Fasciola hybrids and/or parthenogenetic Fasciola may occur. Further studies should also be conducted to determine the presence and role of P. columella in the transmission of Fasciola spp. in these geographical overlaps to help prevent parasite spillbacks.

Morphomolecular characterization of Strongylus vulgaris isolated from donkeys with special references to histopathological study on the affected organs

Equine gastrointestinal tract is infected with Strongylus vulgaris (S. vulgaris) which is highly pathogenic parasite for its harmful effect on cranial mesenteric artery during its migration. So, this study was applied for identification of S. vulgaris in donkeys ultramorphologically and molecularly. In addition to, detection of the pathological effect of larval stage of S. vulgaris on the mesenteric arterial system using histopathology and immunohistochemistry. During the period from September to December; 2019, 60 male and 20 female donkeys at the Giza Zoo was postmortem examined. S. vulgaris adults and larvae were collected from the large intestine and cranial mesenteric arteries (CMAs), respectively. Ultramorphological examination of the collected adults was done using scanning electron microscope (SEM). DNA was extracted from 5 larvae and 6 adults for further conventional PCR studies and sequencing of the internal transcriped spacer 2 (ITS2) gene. The ITS2 gene were amplified and showed bands at 148 base pair (bp). The ITS2 gene nucleotide sequences of all isolates were aligned using Basic Local Alignment Search Tool (BLAST). Histological sections of S. vulgaris affected mesenteric arteries exhibited the presence of the parasite larvae either in the lumen with thrombus formation or attached to the intima. Most of the detected inflammatory cell populations were CD68-positive cells. From these results, it can be concluded that the ribosomal spacers genes could be used as markers for Strongylus species identification in eggs collected from equine feces as a beneficial method of diagnosis. Also, it could be important in disease surveillance, improving preventive measures and developing an effective control strategy.

A Comparison Between Working and Nonworking Donkeys Welfare Issues in Nyala City, South Darfur, Sudan

In impoverished nations, donkeys help people make a living. The welfare of donkeys in Sudan is neglected compared with developed countries. However, there is no information available about donkey welfare in Nyala. This study aimed to assess the welfare of donkeys in Nyala. Donkeys were divided into two groups (n=50), working and nonworking. The donkeys' physical, emotional, and clinial parameters and an owner's interview were assessed. There were significant differences in body condition scores: 37% and 47% of working and nonworking donkeys, respectively, had ideal body condition scores, while 13% of working donkeys were emaciated. Of the working and nonworking 33% and 19% had hoof problems, respectively. Fifteen percent of working donkeys had ocular discharge, and 25% had wounds. In working donkeys, 7% and 5% depressive and aggressive behavioral responses, respectively, were observed. Furthermore, there were significant differences in tools used for hitting donkeys, with 33% and 17% of owners using a stick and whip, respectively, for hitting working donkeys. 82% of owners feed their donkeys one to three times daily (50% working and 32% nonworking donkeys), and free access feeding was only observed in 18% of nonworking donkeys. There were no significant differences (P >0.06) in emotional parameters. We conclude that working donkeys suffer from multiple welfare problems more than nonworking donkeys in Nyala. More awareness, veterinary services, and research are needed to improve donkey care in Nyala.

The equine ascarids: resuscitating historic model organisms for modern purposes

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 condenses known basic biological information and knowledge on the mechanisms of anthelmintic resistance in Parascaris spp., highlighting the importance of foundational research programs. Although two variants of this parasite were recognized based on the number of chromosomes in the 1870s and suggested to be two species in 1890, one of these, P. univalens, appears to have been largely forgotten in the veterinary scientific literature over the past 100 years. We describe how this omission has had a century-long effect on nomenclature and data analysis in the field, highlighting the importance of proper specimen identification in public repositories. A summary of important basic biology, including life cycle, in vitro maintenance, and immunology, is given, and areas of future research for the improvement of knowledge and development of new systems are given. Finally, the limited knowledge regarding anthelmintic resistance in Parascaris spp. is summarized, along with caution regarding assumptions that resistance mechanisms can be applied across clades.

Study on Gastrointestinal Nematodes of Equines in and around Bekoji, South Eastern Ethiopia

Parasitic infections can cause a variety of respiratory, intestinal, and other problems in horses, as well as contribute to some performance issues. A cross-sectional study was undertaken in and around Bekoji, South Eastern Ethiopia, from November 2020 to June 2021 to identify species and evaluate the prevalence of gastrointestinal parasites in donkeys and horses, using direct fecal smear, floatation methods, and larval cultures. In this study, the overall prevalence of gastrointestinal nematode parasites was 94.5% (363 out of 384), with donkeys accounting for 95.8% and horses accounting for 90.5%. The coprological study indicated that an overall prevalence of gastrointestinal nematode parasites was 87%, 8.3%, 2.5%, 1.4%, and 0.8% for mixed parasite infection, nonmigratory strongylids, migratory strongylids, Parascaris equorum, and Oxyuris equi, respectively. Among mixed infections, nonmigratory strongylids+migratory strongylids (51.5%) occurred most frequently. The odds of male horses being infected by GIT nematodes were 1.59 times higher than male donkeys. Horses which have poor body condition were 2.94 times more infected than donkeys. The odds of old-aged donkeys were 3.11 times more infected than horses. A statistically significant difference (p < 0.05) was observed in the prevalence of gastrointestinal nematodes with species and body conditions of the animals. However, no statistically significant difference (p > 0.05) was seen in the prevalence of gastrointestinal nematode parasites between the sex and age of the Equidae. The mean fecal egg count of nematodes revealed that horses (1364.4 ± 483.5) had a more severe infection than donkeys with a statistically significant difference (p < 0.05). The current study determined there was a high prevalence of gastrointestinal nematode parasites in Equidae. Regular deworming, improved housing and nutrition management systems, increased animal owner awareness, and prevention techniques should all be undertaken to minimize the disease's economic burden in the area.

Diversity of gastrointestinal parasites in sympatric mammals in Moukalaba-Doudou National Park, Gabon

Background and Aim: Gastrointestinal parasites identified in the wild can negatively affect host fitness, lower performance, and growth. On the other side, sympatric mammals that share habitat and resources may also cross-transmit parasites, which are often zoonotic and can contribute to morbidity and mortality. This study aimed to characterize the diversity of gastrointestinal parasites circulating in mammalian hosts in Moukalaba-Doudou National Park. Materials and Methods: We screened a total of 25 fecal samples collected from nine wild mammalian species, namely, western gorilla (Gorilla gorilla gorilla), chimpanzee (Pan troglodytes), putty-nosed monkey (Cercopithecus nictitans), African forest elephant (Loxodonta cyclotis), African buffalo (Syncerus caffer), blue duiker (Philantomba monticola), bay duiker (Cephalophus dorsalis), and red river hog (Potamochoerus porcus) as well as people working as trackers (Homo sapiens) using direct microscopic observations following a sedimentation technique to concentrate the fecal material. Results: Of the total 25 fecal samples screened, 15 (60%) were positive for parasitic gastrointestinal infection. Based on the morphology of parasite eggs and cysts, we identified a rich diversity of nematodes, protozoans, trematodes, and cestodes, including unidentified strongyles (73%), Oesophagostomum spp. (53%), Ancylostoma spp. (27%), Trichuris spp. (13%), Ascaris spp. (13%), Mammomonogamus spp. (13%), Strongyloides spp. (47%), Balantidium coli (20%), Entamoeba coli (20%), Endolimax nana (6%), Fasciola hepatica (6%), Paramphistomum spp. (13%), and Taenia spp. (6%). Conclusion: All parasites were found at least once in one of the hosts, and most were potentially zoonotic and responsible for several diseases of public health concern. Because of the small sample size, our findings should not be considered conclusive. Nevertheless, they highlight the diversity of gastrointestinal parasites in this area.

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.

Helminth infections in Italian donkeys: Strongylus vulgaris more common than Dictyocaulus arnfieldi

Donkeys have been used as working animals for transport and farm activities worldwide. Recently, in European countries, there has been an increasing interest in donkeys due to their use as pets, onotherapy or milk production. During 2014-2016, a countrywide survey was conducted to determine prevalence and risk factors of principal helminth infections in 1775 donkeys in 77 Italian farms. A questionnaire on management and parasite control practices was filled out for each farm. Faecal samples were examined using a modified McMaster technique, a centrifugation/flotation method and a sedimentation technique. Pooled coprocultures were performed for differentiation of strongylid eggs. Strongyles were the most common parasites detected (84.9%), followed by Dictyocaulus arnfieldi (6.9%), Oxyuris equi (5.8%), Parascaris spp. (3.6%), Anoplocephala spp. (1.0%), Strongyloides westeri (0.3%). Coprocultures revealed an omnipresence of cyathostomins (100%), followed by Strongylus vulgaris (31.0%), Poteriostomum spp. (25.0%), Triodontophorus spp. (9.0%), Strongylus edentatus (7.0%), Strongylus equinus (5.0%). Logistic regression analysis identified breed, co-pasture with horses, living area, herd size and number of treatments as significantly associated with strongyles. Sex, age, living area and herd size were significantly associated with Parascaris spp. Dictyocaulus arnfieldi was significantly associated with sex, grass, co-pasture with horses, living area and herd size. Strongylus vulgaris was significantly associated with living area and herd size. The mean number of anthelmintic treatments/year was 1.4; most of the donkeys (71.8%) were dewormed using an ivermectin drug. It is important to design parasite programs to specifically address both D. arnfieldi and S. vulgaris in donkeys, and this is especially important if donkeys co-graze with horses.

Gastrointestinal Parasitism in Miranda Donkeys: Epidemiology and Selective Control of Strongyles Infection in the Northeast of Portugal

Simple Summary

In the northeast of Portugal, the Association for the Study and Protection of Donkeys (AEPGA) works to recuperate the autochthonous Miranda do Douro donkey breed. Donkeys living in the three rehabilitation centers of the association have been assessed since 2005 with regards to the parasite control, since parasitism is an important issue affecting their health. Firstly, a strategic approach was implemented for parasite control, but over the years, a lack of anthelmintic efficacy over cyathostomins was observed. Thus, a different strategy was designed, using a targeted selective treatment (TST), and the effects of this approach were studied through the evaluation of parasite dynamics in the animals. Generally, it was observed that TST promoted a rational use of resources, as well as a reduction of parasite prevalence, although with a reduction of parasite biodiversity.

Abstract

In Portugal, equine parasitism in pasture animals is characterized by high parasitic burden and high helminthic biodiversity; both factors are potentially pathogenic for their hosts. The decrease in the number of donkeys over the last years in Portugal, their importance in rural lowland and mountain ecosystems and pastures and the scarce information regarding their parasitism led to this research, which aimed to evaluate the parasitological status of a Miranda donkey breed population, a native breed mainly located in the northeast of Portugal. This study provides better knowledge of their gastrointestinal parasitism, particularly strongyles, and the assessment of a targeted selective treatment (TST) as an alternative control approach of their parasitism. A longitudinal observational study was developed during a period of five years in a population of 62 Miranda donkeys. At first, strategic deworming of these animals was performed every semester, but this was progressively replaced by a TST approach according to the levels of Eggs per Gram (EPG). This new deworming strategy was conducted in association with a regular parasitological monitoring of the animals every three months, being dewormed with ivermectin when egg shedding was higher than 500 EPG. Over the study period, a decrease of the annual prevalence rate of infection by gastrointestinal strongyles was observed, from 35.5% to 19.4%, as well as a negative binomial distribution of parasitic strongyles in donkeys submitted to selective anthelminthic control. The prevalence rate of infection was higher in females (39.5%), in individuals under four years (46.7%) and in those presenting a lower body condition (40.8%). The egg output was higher in animals younger than four years (589.3 EPG) than in those older than 10 years (533.6 EPG) (p < 0.05). However, no differences were observed according to sex during the study period. Results from this study allowed to note the influence of swampy pastures and of the weather changes in the epidemiology of strongylosis in Miranda donkeys. Moreover, it was possible to establish the annual epidemiological curve of strongyle egg shedding, with June being the month with the highest EPG, December having the lowest EPG and March and September showing intermediate numbers. Overall, a lower biodiversity of gastrointestinal parasites was observed. Cyathostomum sensu lato was the most prevalent genus and Strongylus vulgaris was the most observed large strongyle of the Strongylidae family. Trichostrongylus axei and Parascaris sp. were other nematodes with a minor frequency. The higher prevalence of strongyles at the beginning of the study showed a progressive decrease throughout the research period, and also for parasite biodiversity. Therefore, a targeted selective treatment seems to be a rational anthelminthic control approach in Miranda donkey strongyle infection and in other gastrointestinal parasites, since it reduces the antiparasitic treatments, the parasite’ prevalence and the EPG level. However, a loss of parasite biodiversity was noted at the end of the study period, as Cyathostominae were the only isolated strongyles. This can be a challenging situation in the long run, taking the ability of these nematodes to adapt easily to any deworming program, meaning that fecal EPG monitoring should be kept as a rule to a rational parasite control program.

Prevalence of endo- and ecto-parasites of equines in Iran: A systematic review

Equines are subject to infection with many parasites, which threaten their health. In the present study, we systematically reviewed existing literature on the prevalence of endo- and ectoparasites of equines in Iran. Major electronic databases, including PubMed, PubMed Central, Google Scholar, Science Direct and Scientific Information Database (SID), were searched (Last updated 11/05/2018) for relevant literature of parasites that have been identified from equines in Iran. Of the 1809 titles produced by bibliographic search, 38 were included in the review. Twenty-seven of the studies were on horses, six on donkeys, three on both horses and donkeys, and one study was on both horses and mules. Furthermore, 24 of the studies reported infections caused by protozoa, thirteen by helminths, two by ectoparasites, and one by both protozoa and helminths. The overall pooled prevalence of parasitic infection was 28.8% (95%CI: 22.9-35.7, I²  = 93.4%). Helminths were the most prevalent parasites 46.7% (95% CI: 24.1-70.7, I²  = 96.0%). Furthermore, donkeys were the most affected equine, with a prevalence of 70.7% (95% CI: 53.2-83.7, I²  = 92.5%). The protozoa frequently reported included nine species belonging to the genera: Neospora, Toxoplasma, Theileria, Babesia and Eimeria. Also, the helminths frequently reported included 21 species belonging to the genera: Strongylus, Dicrocoelium, Oxyuris, Habronema, Echinococcus, Dictyocaulus, Cyathostomum, Probstmayria, Anoplocephala, Setaria and Fasciola. Ticks were the only ectoparasites frequently reported. Parasitic fly species of the genera Gasterophilus were also reported. The study-level risk of bias was likely to be high because of differences in study design. Parasitic infections of equines in Iran are frequent and caused by a diversity of parasites, which threatens the health and well-being of these animals. Further research is needed in the area to identify the risk factors of infection for effective control of the parasites.

Prevalence and risk factors of gastrointestinal nematode infestation of horses, donkeys and mules in tropical, dry and temperate regions in Mexico

The aims of this study were to determine the prevalence of gastrointestinal nematodes (GIN) in horses, donkeys and mules and its associations with age, sex and climatic factors (derived from satellite data) to identify the potential risk factors of different climate regions in four Mexican states. From May 2017 to April 2018, a total of 560 farm owners or managers answered the questionnaire, and the data were used to establish three Köppen climate classes (tropical, dry, temperate). The overall prevalence of GIN parasites in equines was 77.9% (436 out of 560). The highest percentage of GIN was detected in mules (87.5%). In addition, the highest prevalence among the climate regions was found in the temperate climate (79.9%). The identified nematodes were strongyle type (77.9%), Parascaris equorum (5.7%), Strongyloides (0.7%) and Oxyuris equi (2.9%). The highest mean value of strongylid eggs per g faeces was found in the dry climate (632.6 ± 96.8), followed by that in the tropical climate (518.3 ± 49.7) and temperate climate (383.8 ± 30.2); however, a similar prevalence was observed between different climate regions. Age and sex were identified as risk factors for high shedding of strongyle eggs: the odds ratios for higher shedding intensities were 3.858 for geldings compared to mares, 2.602 for 6-10-year-old equines and 3.597 for ≤16-year-olds compared to young equines (≤5 years old).

Intestinal Strongyle Genera in Different Typology of Donkey Farms in Tuscany, Central Italy

Intestinal strongyles are common helminths of donkeys, in which they may be responsible for disease and poor performance. This study aimed to identify intestinal strongyle genera in 55 naturally infected donkeys from three different farm typologies in Tuscany, central Italy, using morphological and metrical analysis of third stage larvae (L3) obtained from faecal cultures. Larvae were identified using two previous reported morphological identification keys. Moreover, eggs per gram (EPG) data were also evaluated to assess differences, if any, according to the farm typology, sex, and age of the examined donkeys. The results showed that small strongyles were prevalent in all donkey farms. In all examined farms, most (92–100%) of L3 were identified as cyathostomin species of the genera Cylicocyclus spp. and Cylicostephanus spp. Large strongyles of the genera Strongylus spp. and Triodontophorus spp., were identified at low percentage (8%), only in the single organic farm included in the study. A high agreement was observed between the two different morphometric keys used. No significant differences were found for EPG according to farm typology, and sex and age from the examined donkeys. This is the first report about genera identification of intestinal strongyles infecting donkeys in Tuscany, Italy.

Donkey Fascioliasis Within a One Health Control Action: Transmission Capacity, Field Epidemiology, and Reservoir Role in a Human Hyperendemic Area

A One Health initiative has been implemented for fascioliasis control in a human hyperendemic area for the first time. The area selected for this multidisciplinary approach is the Northern Bolivian Altiplano, where the highest prevalences and intensities in humans have been reported. Within the strategic intervention axis of control activities concerning animal reservoirs, complete experimental studies, and field surveys have been performed to assess the fascioliasis transmission capacity and epidemiological role of the donkey for the first time. Laboratory studies with altiplanic donkey-infecting Fasciola hepatica and altiplanic Galba truncatula snail vector isolates demonstrate that the donkey assures the viability of the whole fasciolid life cycle. Several aspects indicate, however, that F. hepatica does not reach, in the donkey, the level of adaptation it shows in sheep and cattle in this high altitude hyperendemic area. This is illustrated by a few-day delay in egg embryonation, longer prepatent period despite similar miracidial infectivity and shorter patent period in the intramolluscan development, lower cercarial production per snail, different cercarial chronobiology, shorter snail survival after shedding end, shorter longevity of shedding snails, and lower metacercarial infectivity in Wistar rats. Thus, the role of the donkey in the disease transmission should be considered secondary. Field survey results proved that liver fluke prevalence and intensity in donkeys are similar to those of the main reservoirs sheep and cattle in this area. Fasciolid egg shedding by a donkey individual contributes to the environment contamination at a rate similar to sheep and cattle. In this endemic area, the pronounced lower number of donkeys when compared to sheep and cattle indicates that the epidemiological reservoir role of the donkey is also secondary. However, the donkey plays an important epidemiological role in the disease spread because of its use by Aymara inhabitants for good transport, movements, and travel from one locality/zone to another, a repercussion to be considered in the present geographical spread of fascioliasis in the Altiplano due to climate change. Donkey transport of parasite and vector, including movements inside the zone under control and potential introduction from outside that zone, poses a problem for the One Health initiative.

Effects of life history stage and climatic conditions on fecal egg counts in plains zebras (Equus quagga) in the Serengeti National Park

In wildlife, endoparasite burden can be affected by host life history stage, environmental conditions, host abundance, and parasite co-infections. We tested the effects of these factors on gastrointestinal parasite infection in plains zebras (Equus quagga) in the Serengeti ecosystem, Tanzania, using fecal egg counts of two nematode families (Strongylidae and Ascarididae) and the presence/absence of cestode (Anoplocephalidae) eggs. We predicted higher egg counts of Strongylidae and Ascarididae, and increased likelihood of Anoplocephalidae infection in individuals (1) during energetically costly life history stages when resource allocation to immune processes may decrease and in young zebras after weaning because of increased uptake of infective stages with forage, (2) when climatic conditions facilitate survival of infective stages, (3) when large zebra aggregations increase forage contamination with infective stages, and (4) in individuals co-infected with more than one parasite group as this may indicate reduced immune competence. Strongylidae egg counts were higher, and the occurrence of Anoplocephalidae eggs was more likely in bachelors than in band stallions, whereas Ascarididae egg counts were higher in band stallions. Strongylidae and Ascarididae egg counts were not increased in lactating females. Strongylidae egg counts were higher in subadults than in foals. Regardless of sex and age, Ascarididae infections were more likely under wet conditions. Co-infections did not affect Strongylidae egg counts. Ascarididae egg counts in adult females were higher when individuals were co-infected with Anoplocephalidae. We present evidence that parasite burdens in plains zebras are affected by life history stage, environmental conditions, and co-infection.

Prevalence of gastrointestinal nematodes, parasite control practices and anthelmintic resistance patterns in a working horse population in Egypt

BACKGROUND

Anthelmintic resistance is commonly reported in horse populations in developed countries, but evidence in some working horse populations is either lacking or inconclusive.

OBJECTIVES

To estimate prevalence of GI nematode infections in working horses in Egypt and to evaluate strongyle resistance to ivermectin, doramectin and fenbendazole.

STUDY DESIGN

Cross-sectional study.

METHODS

Faecal egg count was performed on 644 working horses from 2 provinces in Egypt. A short questionnaire about horse signalment and worming history was completed for each horse. Horses identified with ≥50 strongyle type egg/g (n = 146) underwent faecal egg count reduction testing (FECRT) following treatment with ivermectin (n = 33), doramectin (n = 33) or fenbendazole (n = 30). Risk factors for strongyle (≥200 egg/g) and Parascaris equorum (>0 egg/g) infection were investigated using multivariable logistic regression analyses.

RESULTS

The prevalence of low (0-199 epg), medium (200-500 epg) and high (>500 epg) strongyle infection was 88.4%, 5.9% and 5.8%, respectively. P. equorum eggs were detected in 5.1% (n = 33) of horses. Strongyle FECR was 100%, 99.97% and 100% following treatment with ivermectin, doramectin and fenbendazole respectively. Anthelmintic treatment in the 12 months preceding examination was associated with reduced likelihood of strongyle infection (odds ratio [OR] = 0.26, 95% confidence interval [CI] = 0.14, 0.47, P < .001). The likelihood of P. equorum infection was significantly associated with horses' age (OR = 0.78, 95% CI = 0.69, 0.90; P < .001). Male horses were more likely to have P. equorum infection (OR = 2.86, 95% CI = 1.37, 5.93, P = .005).

MAIN LIMITATIONS

Nonrandomised selection of study areas and larval cultures was unsuccessful for some samples.

CONCLUSIONS

There were low prevalence of strongyle and P. equorum infection and no evidence of macrocyclic lactones or benzimidazole resistance in strongyles in the studied working horse population.

Fasciola hepatica and Fasciola gigantica coexistence in domestic ruminants in Nigeria: application of a PCR-based tool

The distinction between Fasciola hepatica and Fasciola gigantica has been traditionally based on morphological criteria, although accurate recognition of the two flukes is usually difficult because of substantial variations in morphological features. The main aim of this study was to develop a PCR-based assay for discrimination between both species collected in sheep and cattle from Nigeria. A total of 47 animals, 33 cattle and 14 sheep, were sampled, and a single adult fluke was collected from each animal. DNA was extracted from flukes, and primers were designed based on mitochondrial DNA sequences to amplify a 304 bp fragment for the identification of F. hepatica and 752 bp for F. gigantica. PCR products from 12 flukes were sequenced for phylogenetic analysis. A total of 29 out of 47 flukes were identified as F. hepatica and 18 as F. gigantica. Within each host, the percentage of each fluke species was as follows: In cattle, 18/33 (54.5%) and 15/33 (45.5%) were F. hepatica and F. gigantica, respectively. In sheep, 11/14 (78.6%) were F. hepatica and 3/14 F. gigantica (21.4%). The phylogenetic analysis confirmed these results. Although the number of flukes collected in sheep was limited, it seems that F. hepatica is more prevalent in sheep than F. gigantica, whereas the percentage of each species was similar in cattle. This study confirms the presence of F. hepatica in Nigeria.

In Vitro Inhibiting Effects of Three Fungal Species on Eggs of Donkey Gastrointestinal Strongyles

Recently, donkeys have gained popularity mainly due to the use of donkey milk by the cosmetic industry and for human consumption. Gastrointestinal strongyles (GIS) are considered a potential cause of disease and reduced production in infected donkeys. European laws limit the use of anthelmintic drugs for the control of GIS in dairy donkey farms, thus the need to develop alternative control methods. This study aimed to test the in vitro inhibiting effects of three chitin degrading fungi (Scopulariopsis brevicaulis, Metarhizium anisopliae, and Beauveria bassiana) on the hatch and viability of donkey GIS eggs by using the egg hatch test, and to compare their activity to that of Pochonia chlamydosporia. About 150 eggs were added to 0.5 mL of sterile saline solution containing about 1.4 × 10⁸ spores of each fungal species or with 0.5 mL of sterile saline solution only (untreated controls). After incubation, the percentage of egg hatch reduction was calculated, and data were statistically analyzed. All fungi were able to significantly reduce (p < 0.05) the hatch of GIS eggs compared to the untreated controls. Further studies that aim to investigate the efficiency of these fungi in reducing donkey GIS eggs in contaminated environments are encouraged.

Anthelmintic activity of crude powder and crude aqueous extract of Trachyspermum ammi on gastrointestinal nematodes in donkey (Equus asinus): An in vivo study

ETHNOPHARMACOLOGICAL RELEVANCE

Trachyspermum ammi has been used traditionally as a popular ethnobotanical plant in human and animal parasitic infestations. Few scientific studies have been conducted on in vitro anthelmintic activity of T. ammi against various helminths and there is no study on its in vivo/in vitro anthelmintic properties against equine helminths.

AIM OF THE STUDY

The present study aimed to evaluate in vivo anthelmintic activity of crude powder (CP) and crude aqueous extract (CAE) of T. ammi seeds against gastrointestinal nematodes in the donkey.

MATERIALS AND METHODS

Thirty donkeys, naturally and severely infected with Strongyle-type nematodes, were randomly divided into six groups and administered orally with graded doses of CP and CAE at single dose as follow: Two groups were treated with 1 and 3 gkg^-1 body weight of CP, two groups were treated with CAE at the equivalent dose rate 1 and 3 gkg^-1 bw of CP and one group was treated with 200 μgkg^-1 bw of Ivermectin 0.2% (Positive Control). One group received no medication (Negative Control). Efficacy was determined by faecal egg count reduction (FECR) test. The faecal samples were taken from the donkeys on days 7, 14 and 28 post-treatments (PT) and the egg per gram (EPG) of faeces was determined for each animal. FECR for donkeys treated with CP, CAE, and Ivermectin 0.2% was calculated on days 7, 14, and 28 PT. In the present study, CAE was analyzed using gas chromatography-mass spectrometry (GC-MS) to determine CAE chemical components. High-performance liquid chromatography (HPLC) using a marker (thymol) was applied to confirm the existence of thymol as an active principle.

RESULTS

Based on the FECR findings, the maximum FECR (71.2%) was observed in the group treated with CAE₃ on day 14 PT, while it was 66.2% for CP₃ on the same day. The effects of different treatments (P < 0.001), time (P < 0.001) and their interactions (P < 0.05) on EPG showed a significant difference. A dose-dependent response in the anthelmintic activity of CP and CAE was observed. GC-MS analysis indicated that thymol was the major component of CAE (Area = 45.01%) with the respective peak at retention times (Rt) 10.41 min. On HPLC analysis of CAE, thymol was found to be the major constituent of CAE (Area = 58.76%) with the same Rt at 13.233 min.

CONCLUSION

The present study indicated that both CP and CAE of T. ammi had the dose-dependent anthelmintic effects. Due to the development of drug resistance against synthetic anti-helminthics, T. ammi seems to be a promising alternative for the treatment and prevention of helminths in livestock.

Evaluation of a Marketed Polyherbal Dewormer Against Intestinal Strongyles in Naturally Infected Donkeys

The study evaluated the effectiveness of a commercially available polyherbal dewormer to control intestinal strongyles in naturally infected donkeys. The animals were allotted to two groups: treated with the herbal dewormer (n=8) according to manufacturer recommendations and untreated control group (n=6). Fecal samples were taken from each animal on days 0 (day of treatment), 14, 21 (day of second additional treatment), 35, and 42. Faecal egg count reduction tests showed very negligible or no reduction in number of strongyle eggs for donkeys in the phytotherapeutic treatment group compared to those in the control group. Thus, the herbal dewormer was mostly ineffective in reducing fecal egg counts in donkeys infected with intestinal strongyles. These findings can make equine practitioners aware of possible disadvantages of herbal dewormers.

Clinical Pharmacology in Donkeys and Mules

Donkeys and mules show several pharmacodynamic and pharmacokinetic idiosyncrasies that have to be fully considered by any clinician dealing with these species. Because they possess an increased metabolic rate and cellular water content compared with horses, higher doses (or shorter dosing intervals) are usually recommended for those drugs where pharmacologic studies have been performed. Nonetheless, owing to the lack of species-specific information, this assumption cannot be arbitrarily applied. Thus, when a drug protocol published for horses is extrapolated to a donkey or a mule, a close monitoring is required to detect any secondary effect or subdosing.

Determining factors and interspecific modeling for serum amyloid a concentrations in working horses, donkeys, and mules

Serum amyloid A (SAA) is an acute phase protein and α-globulin that is produced in the liver in response to inflammatory cytokines. Considered a major acute phase protein in most domestic species, its concentrations rapidly decrease after resolution of inflammation, making SAA measurement a useful tool for monitoring the course of inflammation in an individual animal. The objective of this study was to compare SAA values in working equids including mules, donkeys and horses as well as values for different diseases at various times of the year. Samples were collected from 77 equids; 13 mules, 17 donkeys and 47 horses from sick or injured animals who presented to the clinic. Twenty-eight disease clinical diagnoses were compared with most cases being acute colitis. A highly significant differences between species was found when comparing SAA concentrations of mules to horses (P < .001) using Dunn comparison pairwise test. A difference (P < .05) was found between donkeys and horses, but not donkeys to mules (P > .05). The study suggests that SAA can be a helpful tool for disease diagnosis in mules and donkeys and suggests that the inflammatory response of mules maybe less than that of horses and donkeys but future studies evaluating SAA in healthy mules compared to diseased should be conducted.

Text Mining Analysis to Evaluate Stakeholders' Perception Regarding Welfare of Equines, Small Ruminants, and Turkeys

Welfare of animals significantly depends on how stakeholders perceive their needs and behave in a way to favor production systems that promote better welfare outcomes. This study aimed at investigating stakeholders' perception of the welfare of equines, small ruminants, and turkeys using text mining analysis. A survey composed by open-ended questions referring to different aspects of animal welfare was carried out. Text mining analysis was performed. A total of 270 surveys were filled out (horses = 122, sheep = 81, goats = 36, turkeys = 18, donkeys = 13). The respondents (41% veterinarians) came from 32 different countries. To describe welfare requirements, the words "feeding" and "water" were the most frequently used in all the species, meaning that respondents considered the welfare principle "good feeding" as the most relevant. The word "environment" was considered particularly important for turkeys, as well as the word "dry", never mentioned for other species. Horses stakeholders also considered "exercise" and "proper training" important. Goat stakeholders' concerns are often expressed by the word "space", probably because goats are often intensively managed in industrialized countries. Although the sample was too small to be representative, text mining analysis seems to be a promising method to investigate stakeholders' perception of animal welfare, as it emphasizes their real perception, without the constraints deriving by close-ended questions.

The prevalence and intensity of external and internal parasites in working donkeys (Equus asinus) in Egypt

Aim

This study aims to record and update the prevalence and intensity of external and internal parasites in working donkeys (Equus asinus) in Egypt during the period from January to December 2017.

Materials and Methods

A total of 120 donkeys (10 donkeys each month) were examined at Giza zoo abattoir through bimonthly visits. The examined donkeys were obtained from five governorates (Giza [20], Fayoum [40], Beni Suef [30], Monofia [20], and Assiut [10]). The animals were grouped according to age and sex.

Results

All examined donkeys were positive with at least one internal or even external parasitic species. The overall prevalence rate was 100%. A total of 11 helminths species (10 nematodes and 1 metacestode); 7 protozoal and 7 arthropod species were collected. The number of each parasite and intensity of infection with regard to age and sex was recorded.

Conclusion

All examined donkeys were infected with parasites with an overall prevalence of 100%. So, we recommended following up and continuous treatment of such diseased animal.

Management practices associated with strongylid parasite prevalence on horse farms in rural counties of Kentucky

Anthelmintic resistance among cyathostomin parasites is a wide-spread problem. The parasite control guidelines written by the American Association of Equine Practitioners (AAEP) encourages the preservation of anthelmintic efficacy by reducing treatment frequency, using targeted deworming, and implementing environmental management practices. While there is knowledge regarding parasite management practices of affluent horse farms in the United States, surveys rarely explore the rural and underserved regions. The purpose of this study was to observe the management practices of horse farms in rural regions Kentucky, including working Amish farms, and determine factors associated with strongyle prevalence. A total of 160 horses among 38 owners from 28 different farms were enrolled in this study. A questionnaire survey regarding equine information, farm management, and deworming history was performed with each owner. Fecal samples were collected to determine fecal egg counts, perform coprocultures for subsequent strongyle larvae identification, and Strongylus vulgaris specific PCR. Serum samples were collected for the S. vulgaris antibody specific ELISA. The mean number of deworming treatments given in the last year was 2.1 with a 95% confidence interval of 1.9-2.3 with ivermectin being the most common active used. Statistical analysis showed horses treated within the last three months with a macrocylic lactone (ML) drug had significantly lower egg counts than horses treated with a ML 7-9 months ago (p = .0005). Despite the AAEP recommendations to reduce the overall number of treatments by using a surveillance-based approach and to no longer rotate treatments, only 17 horses reportedly had a fecal sample submitted for a fecal egg count and 65 horses were dewormed in a rotational manner. Horses whose owners utilized an informative deworming source (i.e., veterinarian, internet, magazine, local feed store) also had significantly lower counts (p = .0026). All coprocultures were negative for S. vulgaris while five horses were PCR positive. Interestingly, 95 horses tested ELISA positive for S. vulgaris. The strongyle egg counts of the working Amish horses were not significantly different from the other horses in this study and deworming practices including the use of efficacious drugs and low treatment frequencies were in accordance with the AAEP guidelines. This study was the first to summarize deworming management practices of rural regions in Kentucky, including a working Amish community. Overall, horse owners employed deworming practices recommended by the AAEP, however rotational deworming is still commonly implemented and fecal egg counts are rarely used.

Occurrence of gastrointestinal parasites in wild animals in State of Paraná, Brazil

The objective of this study was to determine the prevalence and diversity of gastrointestinal parasites in fecal samples from wild birds and mammals from the State of Paraná. In total, 220 stool samples were sent to Parasitic Diseases Laboratory of the Federal University of Paraná during 13 months (Jan/2013-Jan/2014). A total of 52.7% (116/220) of the animals were positive for cysts, oocysts, eggs and/or trophozoites. In birds, the positivity rate was 37.9% (25/66) and mammals was 59.1% (91/154). Strongyloidea superfamily eggs were observed in 37.3% (82/220) of the samples, Eimeria spp. in 10% (22/220), and Trichuris spp. in 4.5% (10/220). The most frequent mammal species were llamas (Lama glama), and dromedaries (Camelus bactrianus) with infection rate of 70.1% (54/77) and 60.8% (14/23), respectively. In other hand, cockatiels (Nymphicus hollandicus) and ring necks (Psittacula krameri), were the most researched birds, with infection rate of 20% (40/50) and 100% (6/6), respectively. A high prevalence of gastrointestinal parasites was observed in most of wildlife animals. Further investigations should be conducted focusing on parasite control strategies and the conservation measurements for harmonizing the human-animal interaction on the long-term, reducing associated health risks.

P-glycoproteins play a role in ivermectin resistance in cyathostomins

Anthelmintic resistance is a global problem that threatens sustainable control of the equine gastrointestinal cyathostomins (Phylum Nematoda; Superfamily Strongyloidea). Of the three novel anthelmintic classes that have reached the veterinary market in the last decade, none are currently licenced in horses, hence current control regimens focus on prolonging the useful lifespan of licenced anthelmintics. This approach would be facilitated by knowledge of the resistance mechanisms to the most widely used anthelmintics, the macrocyclic lactones (ML). There are no data regarding resistance mechanisms to MLs in cyathostomins, although in other parasitic nematodes, the ABC transporters, P-glycoproteins (P-gps), have been implicated in playing an important role. Here, we tested the hypothesis that P-gps are, at least in part, responsible for reduced sensitivity to the ML ivermectin (IVM) in cyathostomins; first, by measuring transcript levels of pgp-9 in IVM resistant versus IVM sensitive third stage larvae (L3) pre-and post-IVM exposure in vitro. We then tested the effect of a range of P-gp inhibitors on the effect of IVM against the same populations of L3 using the in vitro larval development test (LDT) and larval migration inhibition test (LMIT). We demonstrated that, not only was pgp-9 transcription significantly increased in IVM resistant compared to IVM sensitive L3 after anthelmintic exposure (p < 0.001), but inhibition of P-gp activity significantly increased sensitivity of the larvae to IVM in vitro, an effect only observed in the IVM resistant larvae in the LMIT. These data strongly implicate a role for P-gps in IVM resistance in cyathostomins. Importantly, this raises the possibility that P-gp inhibitor-IVM combination treatments might be used in vivo to increase the effectiveness of IVM against cyathostomins in Equidae.

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Pgp-9 transcript levels were higher in ivermectin resistant versus susceptible cyathostomin populations.

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P-gp inhibitors increased ivermectin effect against cyathostomins in vitro.

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P-gp activity may play a role in ivermectin resistance in cyathostomins.

Seasonal variation of strongylosis in working donkeys of Ethiopia: a cross-sectional and longitudinal studies

Helminths are one of the major health problems of working donkeys, often with heavy worm burden and contributing to their early demise and/or reduction in their work output. Cross-sectional and longitudinal studies were conducted to investigate the current infection prevalence and level of strongyles infection donkeys would acquire through different seasons in the mid-lowland agro-ecological zones of Ethiopia. For this purpose, faecal samples from 206 (cross-sectional study) and 102 (longitudinal study) randomly selected donkeys were directly collected from the rectum and analysed. For the longitudinal study, the 102 donkeys dewormed at the end of main rainy season, beginning of October, were monitored for the level of strongyle infection they would acquire during subsequent dry and short rainy seasons. The cross-sectional study of 206 donkey has revealed an overall infection prevalence of 89.3% (95% confidence interval (CI) = 84.4, 92.9). Donkeys in the lowland zone showed a significantly higher strongyle infection prevalence (P = 0.0126) and mean eggs per gramme of faces (EPG) (P = 0.001; 2775 EPG) compared to donkeys in the midland zone (980.8 EPG). Age, sex and body condition did not have any significant effect on either the infection prevalence or level of infection (P > 0.05). The longitudinal study has shown a significantly lower strongyle infection prevalence (P = 0.003) and level of infection donkeys acquired (P = 0.001) in the subsequent dry and short rainy seasons compared to the main rainy season following October deworming. However, these values were not significantly different between the two agro-ecological zones (P > 0.05). This study clearly showed that parasitic infections are primarily acquired during the main rainy season when pasture/herbage coverage is relatively better, and the environment is conducive for parasites survival and development. On the other hand, the finding of majority of donkeys shedding low or no eggs during the dry and short rainy seasons showed that October deworming was effective, and donkeys acquire low or no parasitic infection during the subsequent dry and short rainy seasons. Therefore, the practice of anthelmintic treatment of donkeys at the end of short rain in May may not be necessary, and October deworming once a year is sufficient.

Anthelmintic Resistance of Strongyle Nematodes to Ivermectin and Fenbendazole on Cart Horses in Gondar, Northwest Ethiopia

A study was conducted from November 2015 to April 2016 to determine fenbendazole and ivermectin resistance status of intestinal nematodes of cart horses in Gondar, Northwest Ethiopia. Forty-five strongyle infected animals were used for this study. The animals were randomly allocated into three groups (15 horses per group). Group I was treated with fenbendazole and Group II with ivermectin and Group III was left untreated. Faecal samples were collected from each cart horse before and after treatment. Accordingly, the reduction in the mean fecal egg count at fourteen days of treatment for ivermectin and fenbendazole was 97.25% and 79.4%, respectively. It was significantly different in net egg count between treatment and control groups after treatment. From the study, resistance level was determined for fenbendazole and suspected for ivermectin. In addition, a questionnaire survey was also conducted on 90 selected cart owners to assess their perception on anthelmintics. In the survey, the most available drugs in the study area used by the owners were fenbendazole and ivermectin. Most respondents have no knowledge about drug management techniques. Hence, animal health extension services to create awareness regarding anthelmintic management that plays a key role in reducing the anthelmintic resistance parasites.

Papaya latex supernatant has a potent effect on the free-living stages of equid cyathostomins in vitro

The control of equid gastrointestinal nematodes in developed countries, in particular the cyathostomins, is threatened by high levels of anthelmintic resistance. In recent years, there has been increasing interest in the evaluation of traditional 'ethnoveterinary' medicines as alternatives to chemical anthelmintics. The cysteine proteinases (CPs), a group of enzymes derived from fruits such as papaya (Carica papaya), pineapple (Ananas comosus) and figs (Ficus spp.), have shown good efficacy against adult stages of a range of parasitic nematodes, in vitro and in vivo. The efficacy of CPs against cyathostomins remains to be explored. In this study, the efficacy of a crude preparation of CPs, papaya latex supernatant (PLS), against the free-living stages of cyathostomins was evaluated using two in vitro tests, the egg hatch test (EHT) and the larval migration inhibition test (LMIT). It was demonstrated that PLS had a potent effect in the EHT, with EC-50 values in the range of 0.12-0.22μM. At concentrations above 6.25μM the eggs did not develop, below this concentration the L1 developed but they lost integrity of the cuticle upon hatching. These effects were inhibited by pre-incubation of PLS with the CP inhibitor L-trans-epoxysuccinyl-l-leucylamido-(4-guanidino butane) (E64), indicating that CPs were responsible for the anti-parasitic activity. A dose-dependent inhibition of migration of third stage larvae (L3) in the LMIT was demonstrated at higher concentrations of PLS, with EC-50 values in the range of 67.35-106.31μM. Incubation of PLS with E64 prior to use in the LMIT did not reverse the anti-migratory effect, suggesting that CPs were not responsible for the reduced migration of cyathostomin L3 and that PLS also contains an additional active compound. This is the first report of PLS and/or CPs showing activity against the free-living stages of a parasitic helminth. In addition, it suggests that cyathostomins are highly sensitive to the effects of CPs and further evaluation of their efficacy against parasitic stages and in vivo are strongly indicated.

Monthly variations of Rhinoestrus spp. (Diptera: Oestridae) larvae infesting donkeys in Egypt: Morphological and molecular identification of third stage larvae

This study was carried out to investigate the prevalence and monthly intensity of Rhinoestrus (R) spp. among donkeys slaughtered at Giza Zoo abattoir, Egypt. A total of 144 donkeys were examined at postmortem through two visits per month from January 2010 to December 2010. All donkeys were infested with one or more larval stages during all months of the examination period (100%). The 1st and 2nd stage larvae (L1 and L2) were mostly observed in the turbinate bones and seldom in the nasal passages, whereas the 3rd stage larvae (L3) were observed mostly in ethmoid and lamina cribrosa and rarely in nasal passages and pharynx. The highest monthly intensity of infestation with the total number of larval stages was recorded in January and August, while the lowest occurred in September. L1 was observed during all months with two peaks in January and June. L2 occurred from February to April, July, and August. L3 was present from March to May, August, and September. The ranked size of infestation with the total number of the 3 larval stages of Rhinoestrus spp. showed that a total of 107 donkeys had 1-10 larvae; 34 had 11-30 larvae; and 3 harbored 31-50 larvae. The morphology and molecular characterization of the third stage larvae of Rhinoestrus spp. were investigated. Morphologically, two morphotypes (1 and 2) of Rhinoestrus spp. (R. usbekistanicus like and the other R. purpureus like) were reported. Whereas molecular sequencing of mitochondrial cytochrome-oxidase subunit I showed 99% homology with those of R. usbekistanicus. In conclusion, Rhinoestrus spp. present in Egypt is mainly R. usbekistanicus, which includes two morphotypes, R. usbekistanicus like and R. purpureus like.

Prevalence, intensity and risk factors of infestation with major gastrointestinal nematodes in equines in and around Shashemane, Southern Ethiopia

Prevalence, intensity and risk factors of major gastrointestinal nematode infestation in equines were studied through a cross-sectional survey in 384 equids from October 2013 to April 2014 in and around Shashemane, southern Ethiopia. Three hundred and fifteen equids (82 %) were demonstrated harbouring one or more gastrointestinal (GIT) nematodes using the faecal flotation technique. The prevalence of GIT nematode infestation was 73.4, 85 and 86.5 % for horses, mules and donkeys, respectively. The identified nematodes were strongyle type (73.4 %), Parascaris equorum (21.4 %) and Oxyuris equi (4.4 %). Species of equines had a significant (χ (2) = 9.35, P < 0.01) association with the occurrence of GIT nematode infestation. Donkeys were two times (OR = 2.3, 95 % CI 1.27-4.28, P < 0.01) more likely getting GIT nematode infestation than horses. Moreover, donkeys had the highest mean faecal egg counts (1831.2 egg per gram (EPG)) followed by mules (915.7 EPG) and horses (772.5 EPG). There was a significant association (P < 0.05) between mean EPG and body condition score in each equine species. In conclusion, this study provides information which might help in designing upcoming control strategies to control nematode infestation in equines. Moreover, suitable tropical climatic conditions, low level of management and owners' awareness, and poor animal health services are expected to contribute for high nematode infestation. Therefore, emphasis should be given to awareness creation about the strategic deworming, animal welfare and management.

Larval cyathostominosis in a working donkey

Parasitic infections are one of the most common factors that threaten the health and working performance of donkeys. One of the life threatening parasites is the small strongyles that encyst or burrow into the large intestine and their larvae can initiate severe damage in the lining of the intestine. A 6 years old female donkey with clinical signs of diarrhea and emaciation was necropsied and gross examination of gastro-intestinal tract revealed thin-walled, hyperemic and hemorrhagic cecum. Multifocal petechial hemorrhages were particularly prominent in the submucosa of cecum. Parasitological examination revealed two cyathostomin species included Cylicocyclus elongatus and Cyathostomum pathratum. At microscopic examination, cross sections of cyathostomins larvae associated with parasitic granuloma were observed in the submucosa of cecum. The lesions were associated with non-suppurative enteritis with infiltration of eosinophils, plasma cells, lymphocytes and macrophages in the intestinal mucosa, submucosa and lamina propria.

A survey on the prevalence of strongyles species in working donkeys in North-West of Iran

Faecal samples for detection of gastrointestinal parasites were collected from 60 donkeys from 6 villages in Marand, North-West of Iran. Faecal samples of 2 donkeys (3.33 %) were negative for parasite eggs. 48 positive donkeys (81.66 %) were infected with a single parasite type, 9 (15.51 %) and 1 (1.66 %) of donkeys had multiple infections with two and three parasites, respectively. The highest prevalence and intensity rate belonged to small strongyles. The overall prevalence of intestinal parasites eggs in the positive donkeys were: strongyles 100 %, Parascaris equorum (15.51 %), Habronema spp. 1.72 %. Larval identification showed that small strongyle larvae were most frequent (100 %) followed by Strongylus edentatus (5.17 %), S. equinus (35.71 %) and S. vulgaris (26.66 %). This study revealed that donkeys in Iran are infected with a range of helminths, which are representatives of the important pathogenic parasites found in equids worldwide.

Using physical and emotional parameters to assess donkey welfare in Botswana

INTRODUCTION

Working donkeys in Maun, Botswana contribute to people's livelihoods substantially through the provision of transport, ploughing and income generating activities. However, working donkeys suffer from various welfare issues that were investigated in this study to provide preliminary insights on their health and well-being.

MATERIALS AND METHODS

An assessment protocol involving direct observations of the donkeys was developed and operationalised to assess physical and emotional welfare. Physical welfare parameters such as body condition score, abnormal limbs, impeded gait, eye abnormalities, sore and scar locations, hoof and coat condition were recorded. Emotional welfare parameters such as eyes, tail movement, ear position, neck position, posture and vocalisation were recorded. In addition, donkey-owner interactions were recorded and scored, as well as the donkey's response to environmental factors. A total cross-section of 100 donkeys sub-stratified by roles of riding, cart pulling and resting were randomly selected in eight villages and three urban wards and assessed during the period of May to August 2012.

RESULTS

The findings reveals that the 100 adult working donkeys assessed were physically afflicted by poor BCSs of two (66 per cent), long and cracked hooves (50 per cent), sores on at least two locations on their body (53 per cent), scars on at least two locations on their body (86 per cent), and poor coat conditions (58 per cent). Emotionally, donkeys displayed unresponsiveness (35 per cent), avoidance (31 per cent), disinterest in hand sniffing (59 per cent), dull facial expression (33 per cent), tail stillness (89 per cent), neck stiffness and/or raised head (13 per cent) or head hanging low (32 per cent visibly withdrawn), and tense ears pointing back or to the side (69 per cent). By contrast, the remaining donkeys (31 per cent) exhibited a happy demeanour of curiosity, interest, alert facial expression, tail swishing, relaxed ears pointed to the side or forward and neck relaxed and/or level.

CONCLUSIONS

This study offers preliminary findings from an investigation into the welfare of working donkeys in Greater Maun, Botswana, and provides baseline research to inform future research and strategies to enhance donkey well-being.

Infectious diseases of working equids

Most working equids reside in low-income countries where they have an essential role in the livelihoods of their owners. Numerous infectious diseases negatively impact the health and productivity of these animals. There are considerable technical, social-behavioral, and institutional impediments globally to reducing the burden of infectious diseases on working equids. One the greatest remaining challenges is the lack of funding for research, resulting from the low priority assigned to working equids by funding bodies. Changing the attitudes of decision makers will require data-driven advocacy, and global networks of collaborators have a vital role in building this more robust evidence base.

Helping working Equidae and their owners in developing countries: monitoring and evaluation of evidence-based interventions

There are an estimated 112 million Equidae (horses, donkeys, mules) in the developing world, providing essential resources for their owners' livelihoods and well-being. The impoverished situation of their owners and the often harsh conditions in which they work mean that the animals' welfare is a cause for concern. A number of equine non-governmental organisations (NGOs) operate within working equid communities providing veterinary care, education and training programmes aimed at improving equine welfare. However, there is little published information available that describes monitoring and evaluation (M&E) of such interventions using objective outcome-based indicators and where baseline data are available. The aim of this paper is to summarise the peer-reviewed reports of M&E in this sector and identify the key issues which need to be addressed in ensuring that such evaluations provide useful information on the work of these organisations. A rigorous evidence base for designing future interventions will provide an opportunity for enhancing the effectiveness of working equid NGO operations. Increased availability of M&E reports in the peer-reviewed literature will enable NGOs to learn from one another and disseminate to a wider audience information on the role of working Equidae and the issues they face.

Participatory study of medicinal plants used in the control of gastrointestinal parasites in donkeys in Eastern Shewa and Arsi zones of Oromia region, Ethiopia

Background

Gastrointestinal nematode infections constitute a threat to the health and welfare of donkeys worldwide. Their primary means of control is via anthelmintic treatments; however, use of these drugs has constraints in developing countries, including cost, limited availability, access to cheaper generic forms of variable quality and potential anthelmintic resistance. As an alternative, bioactive plants have been proposed as an option to treat and control gastrointestinal helminths in donkeys. This study aimed to use participatory methodology to explore donkey owner knowledge, attitudes and beliefs relating to the use of plant-based treatments for gastrointestinal parasites of donkeys in Ethiopia.

Results

In focus groups, 22/29 groups stated they knew of plants used for the treatment of gastrointestinal parasites in donkeys. All groups volunteered plants that were used in cattle and/or small ruminants. In total, 21 plants were named by participants. ‘Koso’ (Hagenia abyssinica) ‘Grawa’ (Vernonia amygdalina) and a mixed roots and leaves preparation were the most frequently named plant preparations. ‘Enkoko’ (Embelia shimperi) and ‘a mixture of roots and leaves’ were ranked highly for effectiveness in donkeys. However, ‘Grawa’ and ‘Koso’ were the highest ranked when taking into account both the rank position and the number of groups ranking the plant.

Thematic analysis of participants’ current attitudes and beliefs surrounding traditional plant-based remedies for gastrointestinal parasites revealed that anthelmintics obtained from clinics were generally favoured due to their ease of administration and perceived higher effectiveness. There was doubt surrounding the effectiveness of some plant-based treatments, but there were also perceived advantages including their low cost, ease of cultivation and availability. However, plant-based treatments were considered a “past trend” and people favoured “modern” medicine, particularly among the younger generation.

Conclusions

There was extensive knowledge of plant-based treatments for gastrointestinal parasites in livestock in Ethiopia. In donkeys, Koso (Hagenia abyssinica), Grawa (Vernonia amygdalina), Enkoko (Embelia shimperi) and ‘mixed roots and leaves’ were the most frequently named and/or highest ranked plants with reported efficacy against gastrointestinal parasites. Further in vitro and in vivo investigation of these plants is now required to determine viable alternatives for the treatment and control of gastrointestinal parasites in Ethiopia.