Oesophagostomum stephanostomum causing parasitic granulomas in wild chimpanzees (Pan troglodytes verus) of Taï National Park, Côte d'Ivoire.

Nematodes belonging to the genus Oesophagostomum frequently infect wild chimpanzees (Pan troglodytes) across widely separated field sites. Nodular lesions (granulomas) containing Oesophagostomum are commonly seen in the abdomen of infected chimpanzees post-mortem. At Taï National Park, Côte d'Ivoire, previous studies have identified larvae of a variety of Oesophagostomum spp. in wild chimpanzee stool, based on sequencing of larval DNA, and nodular lesions associated with Oesophagostomum, identified morphologically to the genus level but not sequenced. Here we present three recent cases of parasitic granulomas found post-mortem in chimpanzees at Taï. We complement descriptions of gross pathology, histopathology and parasitology with PCR and sequencing of DNA isolated from the parasitic nodules and from adult worms found inside the nodules. In all three cases, we identify Oesophagostomum stephanostomum as the causative agent. The sequences from this study were identical to the only other published sequences from nodules in nonhuman primates-those from the wild chimpanzees of Gombe, Tanzania.

Novel insight into the genetic diversity of strongylid nematodes infecting South-East and East Asian primates.

With many non-human primates (NHPs) showing continued population decline, there is an ongoing need to better understand their ecology and conservation threats. One such threat is the risk of disease, with various bacterial, viral and parasitic infections previously reported to have damaging consequences for NHP hosts. Strongylid nematodes are one of the most commonly reported parasitic infections in NHPs. Current knowledge of NHP strongylid infections is restricted by their typical occurrence as mixed infections of multiple genera, which are indistinguishable through traditional microscopic approaches. Here, modern metagenomics approaches were applied for insight into the genetic diversity of strongylid infections in South-East and East Asian NHPs. We hypothesized that strongylid nematodes occur in mixed communities of multiple taxa, dominated by Oesophagostomum, matching previous findings using single-specimen genetics. Utilizing the Illumina MiSeq platform, ITS-2 strongylid metabarcoding was applied to 90 samples from various wild NHPs occurring in Malaysian Borneo and Japan. A clear dominance of Oesophagostomum aculeatum was found, with almost all sequences assigned to this species. This study suggests that strongylid communities of Asian NHPs may be less species-rich than those in African NHPs, where multi-genera communities are reported. Such knowledge contributes baseline data, assisting with ongoing monitoring of health threats to NHPs.

Factors associated with strongylida infections in sheep on farms in peri-urban Nairobi, Kenya.

Gastrointestinal parasite infections are among the major limitations to production in sheep in many parts of the world. It is important to continually assess their levels of infection in order to institute control measures and reduce the impact. This study determined the factors associated with the strongylida egg counts in sheep on selected farms in peri-urban Nairobi, Kenya. This was a cross-sectional study in which farm and animal-level data, including faecal samples, were collected from 1640 sheep from 30 purposively selected farms in Ruai, and Kamulu wards in Kasarani sub-county and Utawala and Mihango wards in Embakasi East Sub-County, in Nairobi County Kenya. The faecal samples were subjected to coprological examination using a modified McMaster technique to determine counts of strongylida eggs and coccidia oocysts with a detection level of 100 egg or oocyst per gram (EPG or OPG) of faeces. The positive faecal samples for strongylida eggs were pooled per farm and cultured for morphological identification of larval stage three. Descriptive statistics and multilevel mixed-effect logistic regression analyses were used to determine factors associated with strongylida egg count ≥600 EPG (p < 0.05). The receiver operating characteristics curve was used to assess the overall diagnostic performance in the final model. Strongylida eggs were detected in 45.5% (746/1640) of the sheep, and the mean EPG was 486.0± 858.9 with a median of 200 and a range of 0-16,700. The coccidia oocysts were detected in 49.4% (810/1640) of the sheep with a mean OPG was 341.7± 1782.4, a median of 0 and a range of 0-60,000. In the coprocultures, the nematode genera identified (% differential count of L3) were Haemonchus (90%), Trichostrongylus (5%) and Oesophagostomum (5%). In the final multivariable regression model, the odds of detecting EPG ≥ 600 was 1.44 times higher for sheep shedding coccidia oocysts than those that did not. The odds for detecting EPG ≥ 600 was 4.01 times for sheep in Ruai ward compared with those in the combined Kamulu, Utawala and Mihango wards. The receiver operating characteristic curve area was 73.1%, suggestive of good model performance. The results suggest that gastrointestinal strongylida and coccidia infections are common in sheep and farmers should be educated on the importance of appropriate control measures.

MOLECULAR CHARACTERIZATION OF ORNITHOSTRONGYLUS QUADRIRADIATUS ISOLATED FROM A RACING PIGEON (COLUMBA LIVIA DOMESTICA).

An infestation of Ornithostrongylus quadriradiatus, has been found in a racing pigeon Columba livia domestica). In addition, this individual had a mild infection with Trichomonas spp. and Eimeria spp. The bird showed symptoms of increased appetite; unformed, dark- green feces; and lack of typical male behavior, but the general condition of this pigeon was good. The pigeon was euthanized because of a permanent inability to fly due to an injury to the wing. A postmortem examination revealed the presence of very small dark-pink twisted nematodes with the morphology of O. quadriradiatus in the small intestine, mainly the duodenum. Histopathology showed segmental inflammatory changes in the intestines caused by both blood-sucking nematodes and Eimeria spp. The 5.8S ribosomal ribonucleic acid polymerase chain reaction amplicons from deoxyribonucleic acid extracted from O. quadriradiatus had 82.40% identity with Australostrongylus victoriensis and 81.20% with Travassostrongylus spp. This is the first molecular characterization of O. quadriradiatus-a relatively rare pigeon parasite.

Occurrence and risk factors associated with gastrointestinal parasitism in horses reared in different systems.

To facilitate exploration of the immense range of gastrointestinal parasites in horses and the impact of parasitism on equine health, the present study aimed to evaluate the occurrence and risk factors associated with these infections in horses reared in different management systems in the state of Santa Catarina, Brazil. Samples were collected from 208 horses: 91 from extensive, 64 from semi-extensive, and 53 from intensive rearing systems. The identified helminths included those of the Strongylida order (80.29%), Parascaris equorum (3.36%), Oxyuris equi (4.33%), and Anoplocephala spp. (1.92%). By analyzing the coproculture results to differentiate among Strongylida order parasites, species such as Strongylus vulgaris, S. edentatus, S. equinus, Triodontophorus spp., and Trichostrongylus axei, in addition to members of the Cyathostominae subfamily, which include Gyalocephalus capitatus and Poteriostomum spp., were identified. The only positive sample of protozoa was that of Cryptosporidium spp. (13%). Regarding the rearing system, animals in the extensive system had a higher proportion of infected horses and a higher chance of infection than those in the other systems. For the variable co-grazing with cattle, only cyathostomins showed a significant difference with relatively low infection risk in co-grazing. Overall, the present study demonstrated a high occurrence of equine gastrointestinal parasites, especially those of the Strongylida order, with emphasis on small strongylids. In addition, analyzing factors associated with infection showed that management variables are important for controlling parasitism in horses.

Gastrointestinal parasitic infections in intensive dairy cattle breeding: Update on the epidemiology and associated risk factors in northern Italy.

Parasitic infections such as Strongylida and Eimeria still represent a major health problem of dairy cattle impacting their health, welfare, and productivity. In view of the scarcity of data on risk factors contributing to the spread of parasitic infections in cattle breeding, an epidemiological study in intensive dairy farms in northern Italy was planned. 495 animals (lactating and dry cows, heifers, and calves) from 19 farms were enrolled in the study. Individual fecal samples were analyzed by a quantitative copromicroscopic analysis to detect the number of Strongylida eggs or Eimeria oocysts per gram of faeces (EPG/OPG). Data concerning management, sanitary and biosecurity measures were collected using a questionnaire; a management measures score (MMS) was also calculated. The possible influence of risk factors on Strongylida and Eimeria was thus assessed by statistical analysis using generalized linear mixed models (GLMMs). Eimeria spp. was the most frequently detected parasitic taxon (herd and individual prevalence: 89.5% and 46.2%, respectively), followed by Strongylida (herd and individual prevalence: 63.1% and 16.6%, respectively). The presence of Strongylida resulted associated to the productive category (p-value = 0.028), with heifers and dry cows at higher risk of infection than lactating cows and calves, and to the MMS (p-value = 0.007). Higher prevalence values were recorded in farms with intermediate or low MMS compared to those with optimal MMS. As regard Eimeria infection, a greater effect of MMS on OPG was recorded in calves when compared to those recorded in heifers (OR = 0.228, p-value = 0.003) and dry cows (OR = 0.241, p-value = 0.009). Gastrointestinal parasitic infections still remain an underestimated problem in intensive dairy cattle breeding. MMS may help in the choice of strategies aimed at minimizing the impact of parasites on animal health, thus improving the productivity of the entire herd.

Gastrointestinal symbiont diversity in wild gorilla: A comparison of bacterial and strongylid communities across multiple localities.

Western lowland gorillas (Gorilla gorilla gorilla) are Critically Endangered and show continued population decline. Consequently, pressure is mounting to better understand their conservation threats and ecology. Gastrointestinal symbionts, such as bacterial and eukaryotic communities, are believed to play vital roles in the physiological landscape of the host. Gorillas host a broad spectrum of eucaryotes, so called parasites, with strongylid nematodes being particularly prevalent. While these communities are partially consistent, they are also shaped by various ecological factors, such as diet or habitat type. To investigate gastrointestinal symbionts of wild western lowland gorillas, we analysed 215 faecal samples from individuals in five distinct localities across the Congo Basin, using high-throughput sequencing techniques. We describe the gut bacterial microbiome and genetic diversity of strongylid communities, including strain-level identification of amplicon sequence variants (ASVs). We identified strongylid ASVs from eight genera and bacterial ASVs from 20 phyla. We compared these communities across localities, with reference to varying environmental factors among populations, finding differences in alpha diversity and community compositions of both gastrointestinal components. Moreover, we also investigated covariation between strongylid nematodes and the bacterial microbiome, finding correlations between strongylid taxa and Prevotellaceae and Rikenellaceae ASVs that were consistent across multiple localities. Our research highlights the complexity of the bacterial microbiome and strongylid communities in several gorilla populations and emphasizes potential interactions between these two symbiont communities. This study provides a framework for ongoing research into strongylid nematode diversity, and their interactions with the bacterial microbiome, among great apes.

Abdominal angiostrongyliasis, report of two cases and analysis of published reports from Colombia. / Abdominal angiostrongyliasis, report of two cases and analysis of published reports from Colombia

Abdominal angiostrongyliasis is a parasitic zoonosis, endemic in the American continent. Its etiological agent is Angiostrongylus costaricensis, a nematode whose definitive hosts are rats and other rodents and the intermediate hosts, slugs. Mammals acquire the infection by consuming vegetables contaminated with L3 larvae. The disease shows a heterogeneous clinical spectrum and given its low incidence its diagnosis is a great challenge. In Colombia, the first case was reported in 1979 and until 1998, only five additional cases have been reported. However, in the last two decades, no new cases were reported. Here we discuss two cases of children from Huila and Caquetá departments who developed the disease. Both cases required long in-patient care and multiple surgical interventions. The diagnosis was achieved by histopathological observation of parasitic elements inside the mesenteric arteries. One of the children died while the other fully recovered. We discuss the epidemiology, pathogenic cycle, clinical presentation, diagnosis, and prevention strategies of this disease paying particular attention to our patients' features and the Colombian context.

La angiostrongiloidiasis abdominal es una zoonosis parasitaria endémica en el continente americano. Su agente etiológico es el nematodo Angiostrongylus costaricensis, cuyos huéspedes definitivos son los roedores y, los intermediarios, los caracoles y las babosas, por lo que se adquiere al consumir vegetales contaminados con larvas en estadio 3. La presentación clínica es muy variada y, dada su rareza, su diagnóstico es un desafío. En Colombia el primer caso se reportó en 1979 y, desde entonces hasta 1998, se han informado cinco casos más, aunque en las últimas dos décadas no se había reportado ningún caso. Se describen aquí dos casos de angiostrongiloidiasis en niños provenientes de los departamentos de Huila y Caquetá que requirieron una larga hospitalización y múltiples intervenciones quirúrgicas. El diagnóstico se logró al observar en los especímenes quirúrgicos larvas and huevos cuya morfología sugería una infección por nematodos; uno de los pacientes murió y el otro se recuperó satisfactoriamente. Se discuten la epidemiología, la patogenia, la presentación clínica, el diagnóstico y las estrategias de prevención de esta parasitosis, con énfasis en las características particulares de los casos descritos y en el contexto colombiano.

Abdominal angiostrongyliasis, report of two cases and analysis of published reports from Colombia / Angiostrongiliasis abdominal, reporte de dos casos y análisis de los casos publicados en Colombia

Abdominal angiostrongyliasis is a parasitic zoonosis, endemic in the American continent. Its etiological agent is Angiostrongylus costaricensis, a nematode whose definitive hosts are rats and other rodents and the intermediate hosts, slugs. Mammals acquire the infection by consuming vegetables contaminated with L3 larvae. The disease shows a heterogeneous clinical spectrum and given its low incidence its diagnosis is a great challenge. In Colombia, the first case was reported in 1979 and until 1998, only five additional cases have been reported. However, in the last two decades, no new cases were reported. Here we discuss two cases of children from Huila and Caquetá departments who developed the disease. Both cases required long in-patient care and multiple surgical interventions. The diagnosis was achieved by histopathological observation of parasitic elements inside the mesenteric arteries. One of the children died while the other fully recovered. We discuss the epidemiology, pathogenic cycle, clinical presentation, diagnosis, and prevention strategies of this disease paying particular attention to our patients' features and the Colombian context.

La angiostrongiloidiasis abdominal es una zoonosis parasitaria endémica en el continente americano. Su agente etiológico es el nematodo Angiostrongylus costaricensis, cuyos huéspedes definitivos son los roedores y, los intermediarios, los caracoles y las babosas, por lo que se adquiere al consumir vegetales contaminados con larvas en estadio 3. La presentación clínica es muy variada y, dada su rareza, su diagnóstico es un desafío. En Colombia el primer caso se reportó en 1979 y, desde entonces hasta 1998, se han informado cinco casos más, aunque en las últimas dos décadas no se había reportado ningún caso. Se describen aquí dos casos de angiostrongiloidiasis en niños provenientes de los departamentos de Huila y Caquetá que requirieron una larga hospitalización y múltiples intervenciones quirúrgicas. El diagnóstico se logró al observar en los especímenes quirúrgicos larvas and huevos cuya morfología sugería una infección por nematodos; uno de los pacientes murió y el otro se recuperó satisfactoriamente. Se discuten la epidemiología, la patogenia, la presentación clínica, el diagnóstico y las estrategias de prevención de esta parasitosis, con énfasis en las características particulares de los casos descritos y en el contexto colombiano.

Molecular characterization of nodule worm in a community of Bornean primates.

Strongyles are commonly reported parasites in studies of primate parasite biodiversity. Among them, nodule worm species are often overlooked as a serious concern despite having been observed to cause serious disease in nonhuman primates and humans. In this study, we investigated whether strongyles found in Bornean primates are the nodule worm Oesophagostomum spp., and to what extent these parasites are shared among members of the community. To test this, we propose two hypotheses that use the parasite genetic structure to infer transmission processes within the community. In the first scenario, the absence of parasite genetic substructuring would reflect high levels of parasite transmission among primate hosts, as primates' home ranges overlap in the study area. In the second scenario, the presence of parasite substructuring would suggest cryptic diversity within the parasite genus and the existence of phylogenetic barriers to cross-species transmission. By using molecular markers, we identify strongyles infecting this primate community as O. aculeatum, the only species of nodule worm currently known to infect Asian nonhuman primates. Furthermore, the little to no genetic substructuring supports a scenario with no phylogenetic barriers to transmission and where host movements across the landscape would enable gene flow between host populations. This work shows that the parasite's high adaptability could act as a buffer against local parasite extinctions. Surveys targeting human populations living in close proximity to nonhuman primates could help clarify whether this species of nodule worm presents the zoonotic potential found in the other two species infecting African nonhuman primates.

Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (Lepilemur edwardsi and Avahi occidentalis)?

BACKGROUND: Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward's sportive lemur (Lepilemur edwardsi) and the Western woolly lemur (Avahi occidentalis). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. RESULTS: Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these lemurs, limiting their contact with infective parasite stages. L. edwardsi, which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis, which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes' life cycle. Males and females of both lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals' body condition remains unaffected by the detected gastrointestinal parasites. CONCLUSIONS: The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.

First report of Nematodirus filicollis natural infection in a sheep from the mexican sub-humid tropics / Primer reporte de infección natural de Nematodirus filicollis en un ovino del trópico sub-húmedo mexicano

ABSTRACT Objective. The aim of the present study is to report for the first time the natural infection of a sheep with Nematodirus filicollis in the sub-humid tropics of Mexico. Materials and methods. Faecal samples were processed to identify and quantify faecal nematode eggs per gram of feces (EPG) using the flotation and modified McMaster techniques. Also, faecal cultures were made using the Corticelli-Lai technique. Results. The ewe showed a mixed infection with Trichuris spp. (100 EPG), Nematodirus (100 EPG) and other strongylida nematodes (1500 EPG). The egg size of Nematodirus spp. was 202±3 µ long and 97±2 µ wide. Larvae of Haemonchus, Trichostrongylus, Oesophagostomum and Nematodirus genera were identified from de faecal cultures. Nematodirus larvae averaged 955±8.0 µ long and 28±0.5 µ wide. Whereas, the average length of the sheath tail was 233.4±41.6 µ. Conclusions. According to the morphological traits of eggs and larvae, it is concluded that the infection of the sheep corresponded to Nematodirus filicollis. It is concluded that N. filicollis is able to survive in the sub-humid tropics of Mexico and for the first time an acquired natural infection of this nematode in a sheep is reported.

RESUMEN Objetivo. El presente estudio tiene por objetivo reportar por primera vez el caso de un ovino que adquirió la infección natural con Nematodirus filicollis en condiciones de clima tropical sub-húmedo. Materiales y métodos. Se tomó una muestra de heces que fue procesada para identificar y cuantificar la excreción de huevos de nematodos por gramo de heces (h/gh) mediante las pruebas de Flotación Centrifugada y McMaster. Asimismo, se realizó un cultivo de larvas mediante la prueba de Corticelli-Lai. Resultados. El ovino presentó una nematodiasis mixta por Trichuris spp. (100 h/gh), Nematodirus spp. (100 h/gh) y otros nematodos del orden strongylida (1500 h/gh). El tamaño de los huevos del Nematodirus fue de 202±3 µ de largo y 97±2 µ de ancho. En el cultivo de larvas se identificaron los géneros Haemonchus, Trichostrongylus, Oesophagostomum y Nematodirus. La longitud promedio de las larvas de Nematodirus fue de 955±8.0 µ y ancho de 28±0.5 µ, mientras que la longitud promedio de la cola de la vaina fue de 233.4±41.6 µ. Conclusiones. Con base en las dimensiones de las larvas y sus características morfológicas se reporta que la infección del ovino fue por Nematodirus filicollis. Se concluye que N. filicollis es capaz de sobrevivir en las condiciones del clima tropical sub-húmedo en México y se reporta por primera vez el caso de un ovino que adquirió la infección natural con este nematodo.

Reliability of different methods of diagnosing intestinal parasites in horses

Parasitism by intestinal nematodes may cause serious injuries to equines affecting their performance, given that the parasites compete for food and cause irritation, internal bleeding and anaemia. The diagnostic methods currently available are not efficient in detecting all the species of parasites simultaneously, hampering reliable diagnosis. Therefore, the purpose of this study was to evaluate four diagnostic methods for detecting equine intestinal parasites in the southern hinterland of Pernambuco, Brazil. Fecal samples (n = 87) were collected and examined through flotation based methods (Willis-Mollay, modified centrifugal flotation and EPG/OPG) and sedimentation (Hoffman). Of the total number of samples examined, 77.0% (67/87) were positive by modified centrifugal flotation; 44.8% (39/87) were positive by the Willis-Mollay method; 34.5% (30/87) by the Hoffman method and 28.7% (25/87) by the EPG/ OPG method. The Kappa index indicated moderate concordance between the Willis-Mollay and modified centrifugal flotation techniques (K= 0.477); Willis-Mollay and EPG/OPG (K= 0.466); EPG/OPG and Hoffman (K= 0.425). In conclusion, modified centrifugal flotation presented high sensitivity for detection of parasites of the Strongylida order and Parascaris spp. It may, therefore, be used in association with the Willis-Mollay technique as a safe and accurate method of diagnosis.

Speciation in the genus Cloacina (Nematoda: Strongylida): species flocks and intra-host speciation.

Sequences of the first and second internal transcribed spacers (ITS1 + ITS2) of nuclear ribosomal DNA were employed to determine whether the congeneric assemblages of species of the strongyloid nematode genus Cloacina, found in the forestomachs of individual species of kangaroos and wallabies (Marsupialia: Macropodidae), considered to represent species flocks, were monophyletic. Nematode assemblages examined in the black-striped wallaby, Macropus (Notamacropus) dorsalis, the wallaroos, Macropus (Osphranter) antilopinus/robustus, rock wallabies, Petrogale spp., the quokka, Setonix brachyurus, and the swamp wallaby, Wallabia bicolor, were not monophyletic and appeared to have arisen by host colonization. However, a number of instances of within-host speciation were detected, suggesting that a variety of methods of speciation have contributed to the evolution of the complex assemblages of species present in this genus.

Gender and developmental specific N-glycomes of the porcine parasite Oesophagostomum dentatum.

BACKGROUND: The porcine nodule worm Oesophagostomum dentatum is a strongylid class V nematode rather closely related to the model organism Caenorhabditis elegans. However, in contrast to the non-parasitic C. elegans, the parasitic O. dentatum is an obligate sexual organism, which makes both a gender and developmental glycomic comparison possible. METHODS: Different enzymatic and chemical methods were used to release N-glycans from male and female O. dentatum as well as from L3 and L4 larvae. Glycans were analysed by MALDI-TOF MS after either 2D-HPLC (normal then reversed phase) or fused core RP-HPLC. RESULTS: Whereas the L3 N-glycome was simpler and more dominated by phosphorylcholine-modified structures, the male and female worms express a wide range of core fucosylated N-glycans with up to three fucose residues. Seemingly, simple methylated paucimannosidic structures can be considered 'male', while methylation of fucosylated glycans was more pronounced in females. On the other hand, while many of the fucosylated paucimannosidic glycans are identical with examples from other nematode species, but simpler than the tetrafucosylated glycans of C. elegans, there is a wide range of phosphorylcholine-modified glycans with extended HexNAc2-4PC2-4 motifs not observed in our previous studies on other nematodes. CONCLUSION: The interspecies tendency of class V nematodes to share most, but not all, N-glycans applies also to O. dentatum; furthermore, we establish, for the first time in a parasitic nematode, that glycomes vary upon development and sexual differentiation. GENERAL SIGNIFICANCE: Unusual methylated, core fucosylated and phosphorylcholine-containing N-glycans vary between stages and genders in a parasitic nematode.

Detection of cryptic species of Rugopharynx (Nematoda: Strongylida) from the stomachs of Australian macropodid marsupials.

Sequences of the internal transcribed spacers of nuclear ribosomal DNA (ITS-1 and ITS-2) were determined for species of the genus Rugopharynx and Rugonema labiatum, nematodes from the stomachs of macropodid marsupials. Phylogenetic analyses of the aligned sequence data were conducted. The relationships provided molecular support for all species currently recognised, some of which are based on minor morphological differences and on multilocus enzyme electrophoretic data, but also indicated that additional, cryptic species exist within the genus. In addition, the genus Rugonema is placed as a synonym of Rugopharynx, its sole species becoming Rugopharynx labiatum n. comb. The molecular data provided some insights into the evolution of complex buccal capsule morphologies within the genus, but there was no evidence of co-evolution between the macropodid hosts and their parasites.

Understanding Haemonchus contortus Better Through Genomics and Transcriptomics.

Parasitic roundworms (nematodes) cause substantial mortality and morbidity in animals globally. The barber's pole worm, Haemonchus contortus, is one of the most economically significant parasitic nematodes of small ruminants worldwide. Although this and related nematodes can be controlled relatively well using anthelmintics, resistance against most drugs in common use has become a major problem. Until recently, almost nothing was known about the molecular biology of H. contortus on a global scale. This chapter gives a brief background on H. contortus and haemonchosis, immune responses, vaccine research, chemotherapeutics and current problems associated with drug resistance. It also describes progress in transcriptomics before the availability of H. contortus genomes and the challenges associated with such work. It then reviews major progress on the two draft genomes and developmental transcriptomes of H. contortus, and summarizes their implications for the molecular biology of this worm in both the free-living and the parasitic stages of its life cycle. The chapter concludes by considering how genomics and transcriptomics can accelerate research on Haemonchus and related parasites, and can enable the development of new interventions against haemonchosis.

Effect of zinc supplementation on ecto-adenosine deaminase activity in lambs infected by Haemonchus contortus: highlights on acute phase of disease.

Haemonchus contortus (order Strongylida) is a common parasitic nematode infecting small ruminants and causing significant economic losses worldwide. It induces innate and adaptive immune responses, which are essential for the clearance of this nematode from the host. Ecto-adenosine deaminase (E-ADA) is an enzyme that plays an important role in the immune system, while Zinc (Zn) has been found playing a critical role in E-ADA catalysis. Therefore, the aim of this study was to assess the effect of Zn supplementation on E-ADA activity in serum of lambs experimentally infected with H.contortus. To reach this purpose 28 male lambs (in average 25 kg) were used. The animals were divided into four groups: A and B composed of healthy animals (uninfected); C and D, infected with H.contortus. Groups B and D were supplemented with Zn Edetate, subcutaneously with 3 mg kg of live weight, on days 11 and 25 post-infection (PI). Blood and fecal samples were collected on the days 11, 25 and 39 PI, in order to assess hematocrit, seric E-ADA, and eggs per gram (EPG) counting, respectively. The animals of groups C and D showed severe hematocrit reduction (days 25 and 39 PI) and were EPG positive (days 11, 25 and 39 PI). On day 41 PI, three animals each group were subjected to necropsy. This procedure showed that animals of groups A and B did not have helminths in abomasum and intestines, while H.contortus were observed in groups C (5782.5 ± 810.9) and D (6185.0 ± 150.0). Infected and untreated animals (group C) showed a reduction in E-ADA activity, but this was not observed when the animals were supplemented with Zn (Group D). Therefore, based on our results, it was possible to observe that Zn supplementation exercised a positive effect on E-ADA activity in lambs infected with H.contortus, and did not allow a reduction in E-ADA activity, as occurred in the group infected and without supplementation. However, Zn supplementation was not able to prevent the worm burden.

Profiles of strongyle EPG values for Thoroughbred mares on 14 farms in Kentucky (2012-2013).

The main purpose of the research was to determine if three weekly samplings would produce consistent results for low strongyle egg shedders, generally associated with older horses. Strongyle egg counts per gram of feces (EPG) were done for 661 Thoroughbred mares on 14 farms in 2012-2013 once a week for three consecutive weeks. None of the mares had been treated with ivermectin or moxidectin for more than 90 days and with fenbendazole, oxibendazole, or pyrantel pamoate for more than 60 days. Strongyle EPG count data indicated that 38.3% of the mares were positive at first and second sampling, and 37.8%--at third sampling. There were 5.6-63.3% of horses positive per farm. Correlations between EPG count data in all three weeks are quite high (Rs = 0.84, p<0.001). Level of horse infection was found to be dependent on horse age, type of farm and individual characters of horse. This study documented that strongyle egg counts (EPGs) from individual horses did not differ significantly between weeks. Thus, a single strongyle EPG count can be interpreted as indicative of the level of egg shedding for a given horse. These data support the current trend of not deworming all adult horses on a farm, so that high shedders can be identified and treated. This saves horse owners money and reduces development of potential drug resistance of parasites because of less frequent usage of antiparasitic compounds. Information from this study helps to conclude recommendations for parasite control in horses globally.

Comparative morphology of the species of Libyostrongylus and Codiostomum, parasites from ostriches, Struthio camelus, with a identification key to the species / Morfologia Comparativa das espécies de Libyostrongylus e Codiostomum, parasitas de avestruzes, Struthio camelus, com uma chave para identificação das espécies

One of the most common problems in breeding of ostriches in captivity is the control of parasitic diseases. This work presents keys for the identification of adult nematodes and infective larvae by morphologic and morphometric characteristics. These keys will allow the scientific community to identify the species that infect the ostriches either based on the characteristics of the posterior end of the infective larvae found through a simple fecal exam or by observing the morphology and morphometry of adult worms recovered during necropsies. These keys will facilitate ecological and systematic studies, as well as increase the understanding of the epidemiology of these parasitosis in ostriches.

Um dos problemas mais comuns na criação de avestruzes em cativeiro é o controle das doenças parasitárias. Este trabalho apresenta chaves para a identificação de Nematoda adultos e larvas infectantes através de caracteres morfológicos e morfométricos. Essas chaves de identificação permitirão à comunidade científica o diagnóstico das espécies que infectam as avestruzes com base nas características da extremidade posterior das larvas infectantes encontradas por meio de simples exames fecais ou pela observação da morfologia e morfometria dos espécimes adultos recuperados durante necropsia. Dessa forma, as chaves de identificação facilitarão os estudos ecológicos e sistemáticos, bem como a melhor compreensão da epidemiologia dessas infecções em avestruzes.