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This investigation was aimed to evaluate the use of an oral bio-preparation containing Duddingtonia flagrans chlamydospores for the control of sheep gastrointestinal parasitic nematodes under the Mexican cold high plateau conditions. Two groups of gastrointestinal parasitic nematode naturally infected sheep, were randomly selected and located into two free-gastrointestinal nematode larvae paddocks. Group 1 received once a week a supplement containing D. flagrans chlamydospores mixed with oats and molasses. Group 2 received a similar supplement without any fungal material. After 5 months grazing animals were discarded from the experiment and two groups of free-nematode "tracer" sheep were located into the same paddocks to collect larvae from the contaminated pastures. Animals were slaughtered and necropsied and the nematodes were obtained and counted. A screening of the number of gastrointestinal nematode larvae present on the grass was performed and compared between the two grazing areas. The results showed 56% reduction in the Ostertagia (Teladorsagia) circumcincta and 94% reduction in the Nematodirus sp. population of the "tracer" sheep who grazed on the D. flagrans-treated sheep area, compared to the nematode population in animals grazed on the non-treated area. The results of the number of larvae on the grazing pastures showed a 51.1% reduction for H. contortus, and 100% for Cooperia sp. in the area with fungi. In the case of Trichostrongylus sp. no reduction was observed, when compared to the control group.

Feces from 62 captive African gazelles, including Mhorr gazelles (Gazella dama mhorr), Cuvier's gazelles (Gazella cuvieri), and Dorcas gazelles (Gazella dorcas neglecta), were examined over the course of a year to quantitate nematode egg excretion patterns. Strongyloides sp. eggs appeared only in G. dama during the rainy season. Trichostrongylidae egg excretion showed a marked seasonal variation, with very low levels during the dry and hot period, a finding that is probably attributable to hypobiosis of the predominant species (Camelostrongylus mentulatus). Eggs of the Nematodirus sp., predominantly Nematodirus spathiger, were excreted throughout the year. No seasonal pattern was observed in Trichuris sp. egg excretion.

Regulation of ungulate populations by parasites relies on establishing a density-dependent relationship between infection and vital demographic rates which may act through the effect of parasites on body condition. We examine evidence for parasite impacts in 285 red deer (Cervus elaphus) harvested during 1991 and 1992 on the Isle of Rum. In the abomasa, prevalence of nematodes was 100% and the most abundant genus observed wereOstertagiaspecies, however, mean intensity of infection was low (less than 1000) relative to other studies. Additional species, also present in low numbers, includedNematodirusspp.,Capillariaspp.,Cooperiaspp., Monieza expanza,Oesophagostomum venulosumandTrichuris ovis. Lungworm (Dictyocaulusspp.) and tissue worm (Elaphostronygylus cervi) larvae were also observed in faecal samples. There was no evidence for acquired immunity to abomasal nematodes. Despite low levels of infection, both adult male and female deer showed significant negative correlation between indices of condition (kidney fat index, dressed carcass weight and larder weight) and intensity ofOstertagiaspp. infection. However, there was no evidence that pregnancy rate in females was related to intensity of infection. For calves, there was no relationship between body condition and intensity of infection. The apparent subclinical effects of low-level parasite infection on red deer performance could alternatively be due to animals in poorer nutritional state being more susceptible to infection. Either way the results suggest that further studies of wild populations are justified, in particular where high local host densities exist or alternative ungulate hosts are present, and, where experimental treatments are tractable.

A coprological survey to know the presence of gastro-intestinal nematode parasites infecting sheep was done in Galicia (NW Spain), an area with Atlantic climate where sheep production is replacing cattle due to the Agricultural Community Politics of the European Union. From September 2001 to November 2002, 1710 faecal samples were randomly collected from 49 sheep farms and examined by using the flotation technique to determine the prevalence of gastro-intestinal nematode parasites. The sheep-level prevalence was 100%, and the genera identified were Chabertia, Cooperia, Haemonchus, Nematodirus, Oesophagostomum, Teladorsagia, Trichostrongylus and Trichuris spp. A questionnaire was distributed to the farmers (at the same time as sampling) about parasite-control practices during the year before sampling (2000). Ninety percent (95% CI 81%, 98%) of the farmers said they used antiparasitic drugs occasionally, but none of them asked for a coprological analysis prior to the treatment and the efficacy of the drugs was never evaluated. A higher median EPG was observed in the treated sheep (163) than in the untreated ones (26). Chemotherapy was the only parasite-control practice. Flocks that treated according to the farmer's previous experience had higher median EPG (236) than other flocks (185 following the prescription of their veterinary clinician and 232 based on the commercial agent's counsel). Typically, one benzimidazole-treatment per year was applied in autumn and non-veterinary counsel was used. Sheep treated with imidotiazoles had lower EPG (144) than other drugs (164 for the benzimidazoles and 166 for the macrocyclic lactones). We found a higher median EPG in the sheep receiving two treatments/year (175) than in those treated only once per year (156). These results suggest lack of knowledge about worm-control strategies and anthelmintic use or unwillingness to apply such knowledge.

In order to evaluate the epidemiology of parasitism in farmed ruminants in the changed agricultural context in Kazakhstan, 505 cattle, sheep and goats were surveyed for gastrointestinal parasitism using coprological examination, and a further thirty sheep and four goats using post mortem extraction of helminths. The dominant helminth genera were Marshallagia, Nematodirus and Trichostrongylus. Haemonchus was also present. Faecal egg counts were low (mean abundance 0-115 eggs per gram in different groups), and there was no relationship between faecal egg density and body condition score. Eggs of Nematodirus spp. were more common in sheep less than 1 yr of age, whereas those of the Trichostrongylidae were generally more common in adult sheep. Based on faecal egg counts, sheep grazing on common land close to permanent human settlements were generally no more heavily infected than those grazing the remote open plains. This could be due to a non-linear relationship between livestock numbers and stocking density. We suggest that cessation of strategic nematode control in the region following post-Soviet agricultural reform was offset by a general reduction in stocking density, such that parasite burdens remained low. However, recovery in livestock numbers is likely to lead to increased levels of infection and production loss unless sustainable control strategies are put in place.

This study aimed to identify quantitative trait loci associated with endoparasitic infection in Scottish Blackface sheep. Data were collected from 789 animals over a 3-year period. All of the animals were continually exposed to a mixed nematode infection by grazing. Faecal samples were collected in August, September and October each year at ca. 16, 20 and 24 weeks of age; Nematodirus spp. eggs were counted separately from the other species of nematodes. Blood samples were collected in October from which immunoglobulin A (IgA) activity was measured and DNA was extracted for genotyping. In total, 139 Microsatellite markers were genotyped across eight chromosomal regions (chromosomes 1, 2, 3, 5, 14, 18, 20 and 21) in the sires and progeny were genotyped for the markers that were polymorphic in their sire. Evidence was found for quantitative trait loci (QTL) on chromosomes 2, 3, 14 and 20. QTL associated with specific IgA activity were identified in chromosomes 3 and 20, in regions close to IFNG (chromosome 3) and the MHC (chromosome 20). QTL associated with Nematodirus FEC were identified on chromosomes 2, 3 and 14. Lastly, QTL associated with non-Nematodirus Strongyle FEC were identified on chromosomes 3 and 20. This study has shown that some aspects of host resistance to gastrointestinal parasites are under strong genetic control, therefore these QTL could be utilised in a marker-assisted selection scheme to increase host resistance to gastrointestinal parasites.

International audience; Benzimidazole resistance is common amongst many ovine trichostrongylid nematodes species globally. Although anthelmintics have been used for over half a century in some areas of the world for the control of Nematodirus battus, resistance has never been detected. Veterinary investigations conducted in 2010 demonstrated reduced efficacy in a flock that had been treated previously with fenbendazole (FBZ), suggesting probable resistance in N. battus. Infective larvae (L3; designated MNba2) were generated from the original material to conduct a controlled efficacy test (CET). Faecal egg counts showed an average of 37% reduction in the FBZ treated group 7 days post treatment compared to the untreated lambs. Average worm burden results showed no reduction after FBZ treatment compared to the untreated group (3850 and 3850 worms respectively). A molecular assay to assess the frequency of the commonly associated single nucleotide polymorphisms (SNP) in the β-tubulin isotype 1 gene, F200Y and E198A, was developed. Larval genotypes were predominantly homozygous resistant at codon 200 SNP, ranging from 56%-83% and remained stable at 70% for adult worm populations taken from treated and control lambs in the CET. Only susceptible genotypes were found at codon 198. The allele frequency for F200Y ranged between 80-83% in adult worms taken from the CET from treated and control lambs. The results confirmed initial findings and demonstrated the first report of FBZ resistance in N. battus whilst providing evidence that the P200 point mutation in the β-tubulin isotype 1 gene is a potential mechanism of resistance in the species.

International audience; Gastrointestinal nematode infections are one of the main health/economic issues in sheep industries, worldwide. Indicator traits for resistance such as faecal egg count (FEC) are commonly used in genomic studies; however, published results are inconsistent among breeds. Meta (or joint)-analysis is a tool for aggregating information from multiple independent studies. The aim of this study was to identify loci underlying variation in FEC, as an indicator of nematode resistance, in a joint analysis using data from three populations (Scottish Blackface, Sarda × Lacaune and Martinik Black-Belly × Romane), genotyped with the ovine 50k SNP chip. The trait analysed was the average animal effect for Strongyles and Nematodirus FEC data. Analyses were performed with regional heritability mapping (RHM), fitting polygenic effects with either the whole genomic relationship matrix or matrices excluding the chromosome being interrogated. Across-population genomic covariances were set to zero. After quality control, 4123 animals and 38 991 SNPs were available for the analysis. RHM identified genome-wide significant regions on OAR4, 12, 14, 19 and 20, with the latter being the most significant. The OAR20 region is close to the major histocompatibility complex, which has often been proposed as a functional candidate for nematode resistance. This region was significant only in the Sarda × Lacaune population. Several other regions, on OAR1, 3, 4, 5, 7, 12, 19, 20 and 24, were significant at the suggestive level.

Helminth infection acquired by lambs grazing on pastures fertilised either by urban sewage sludge or cattle slurry were studied in temperate Central Western France. The aim was to assess the risk of larval cestodoses in lambs after sewage application and of digestive tract nematode infection following the slurry application. Twenty-six sheep were allocated on two paddocks of 0.7 ha, one fertilised with sludge and the other with cattle slurry. The delay between application and actual grazing was 6 weeks; grazing on these paddocks extended from mid July to beginning of November 2002. The herbage biomass was slightly increased in the sludge paddock but it did not result in an increase of lamb live weight, compared with the slurry paddock. The lambs did not acquire cysticercosis or any other larval cestodoses in the sewage sludge group and only very limited infections with Cooperia spp. and Nematodirus spp. were observed in the slurry group. It was concluded that in our conditions the helminth risk was extremely low and was not a cause of restriction of the use of these biowastes.

Monophyly for the Nematodirinae, with 5 genera, Murielus, Rauschia, Nematodiroides, Nematodirus, and Nemato- dirella was confirmed based on comparative morphology and phylogenetic analysis of structural characters. This concept for the nematodirines excludes the monotypic Lamanema chavezi, but otherwise corroborates generic-level diversity as defined in prior studies. Exhaustive analysis resulted in 1 most parsimonious tree (36 steps; consistency index (CI) 5 0.94; retention index (RI) 5 0.93; excluding phylogenetically uninformative characters, CI 5 0.92). As an inclusive or monophyletic group, Nematodirinae was diagnosed by 8 synapomorphies (7 are unequivocal): (1) large eggs, (2) long filiform spicules, (3) basal division of the dorsal ray, (4) symmetrical membrane enveloping the spicule tips, (5) fused structure of the spicule tips, (6) absence of the gubernaculum, (7) development of the third-stage larva within the egg, and (8) ornamentation in the form of discrete bosses on the bursa. Exclusion of Lamanema will require new assessments of historical biogeography and the evolution of host associations for the nematodirines. Nematodirine nematodes globally represent serious patho- gens in wild mammals and domestic stock. The speciose genus Nematodirus Ransom, 1907, contains an array of helminth path- ogens that infect ruminants throughout the world, and species such as Nematodirus battusCrofton and Thomas, 1951, contin- ue to be regarded as among the most economically significant parasites in domestic sheep, Ovis aries Linnaeus, across the Northern Hemisphere (e.g., Thomas and Stevens, 1956; Ho- berg, Zimmerman, and Rickard, 1985; Hoberg, 1997). Although there has been considerable effort and research to define epi- zootiology, and the host-parasite interface for species of Nem

Genetic analyses were carried out on Nematodirus spp. egg counts (NEM) of lambs from a set of Romney breeding lines. The lines had been under selection for 22 seasons (1979 to 2000) for divergence in resistance to infection by strongyle nematodes other than NEM, using faecal egg count (FEC) as the selection criterion. Heritabilities and genetic correlations for NEM were estimated using residual maximum likelihood procedures. Correlated responses in NEM were also determined. Heritability estimates for loge(NEM + 100) in lambs at 4 months of age (NEM1) or 6 months of age (NEM2) were 0·15 (s.e. 0·03) and 0·26 (s.e. 0·04) respectively (c.f. 0·28 (s.e. 0·02) and 0·35 (s.e. 0·02) for loge(FEC + 100)). The genetic correlation between loge(NEM1 + 100) and loge(NEM2 + 100) was 0·85 (s.e. 0·08), while the genetic correlations between measurements of loge(NEM + 100) and loge(FEC + 100) on both sampling occasions had a weighted average of 0·43, with estimates ranging from 0·30 (s.e. 0·08) to 0·52 (s.e. 0·07). Divergence in loge(NEM + 100) between the high and low FEC lines, estimated over both sampling times combined, was 1·07 phenotypic standard deviations, compared with 3·6 phenotypic standard deviations for loge(FEC + 100). Expressed in terms of back-transformed eggs per g, the high and low FEC lines differed by factors of 7·6 and 32·2 for NEM and FEC, respectively. The results support earlier parasitological data indicating that the genetic mechanisms in sheep which are responsible for resistance to other strongyle nematodes probably also influence resistance to Nematodirus infection.

WE would like to report the identification of Nematodirus lamae in an 18-month-old alpaca ( Vicugna pacos ) submitted for postmortem examination to the Animal and Plant Health Agency (APHA) Carmarthen Veterinary Investigation Centre in January 2016. To the authors' knowledge, this parasite has not previously been reported outside South America. The animal, initially one of eight on the holding, had been found dead on the morning of submission. Another animal, an adult female from the same group, had died two weeks previously after a period of recumbency, but had not been submitted for investigation. They had last received an anthelmintic treatment 14 months previously. All the alpacas on the holding had been bred in the UK. One was known to have been born to an imported dam. On necropsy, examination of the third stomach compartment (C3) detected …

Exotic wildlife can introduce new diseases or act as reservoirs of endemic diseases. On White Sands Missile Range, New Mexico (USA), significant declines in populations of native ungulates generally correspond to increases in range and population density of the exotic gemsbok (Oryx gazella gazella), introduced beginning in 1969. We surveyed gemsbok in 2001 for exposure to a variety of diseases potentially important for native ungulates. High seroprevalence was found for malignant catarrhal fever virus (49 [98%] of 50 sera; 43 [96%] of 45 plasma samples), blue-tongue virus (48 [96%] of 50), bovine respiratory syncytial virus (33 [66%] of 50), and parainfluenza-3 virus (10 [20%] of 50). Low numbers of Nematodirus spp. eggs in a few individuals were the only parasites detected in gemsbok. Exposure to the above diseases in gemsbok is of interest to managers because of potential implications for recovery of desert bighorn sheep (Ovis canadensis mexicana) and desert mule deer (Odocoileus hemionus crooki) in the White Sands area because each has been implicated in mortality in these species either in the White Sands area or elsewhere in the western/southwestern United States.

A parasitologic survey for internal parasites was done at routine necropsy of cattle (N = 142) and horses (N = 190, including 1 donkey) at the Livestock Disease Diagnostic Center, University of Kentucky, in 2000 and 2001. The eyes, esophagus, lungs, rumen, and feces were examined from the cattle, and the small intestine was scrutinized from the horses. Endoparasites recovered from the cattle (percent infected) were Thelazia skrjabini (13%) and Thelazia gulosa (8%) from the eyes. One or both Thelazia species were recovered from 16% of the cattle, and Gongylonema pulchrum (2%) was recovered from the esophagus. The types of eggs present in the feces of cattle (percent positive) were Haemonchus–Ostertagia–Trichostrongylus (53%), Nematodirus (13%), Strongyloides (3%), Trichuris (3%), Capillaria (1%), and Moniezia (4%). Lungworm (Dictyocaulus viviparus) larvae were not detected in cattle feces. No parasite was found in the lungs or rumen of necropsied cattle. Parasites found in the small intestine of t...

Objective To compare two strategies for the preparation of pastures that have reduced trichostrongylid infections during winter and spring for Merino weaners. Design A replicated field experiment was conducted over two successive years. A ‘standard’ strategy, comprising set-stocked wethers given anthelmintic treatments in late October and early February, was compared with a ‘new’ one in which intensive grazing for 1 month after each treatment and destocking for 1 or 2 months was integrated with the anthelmintic treatments. Paddocks prepared according to these strategies were set-stocked at 15 Merino weaners/ha from April to October inclusively. Results Contamination of pastures prepared according to the new strategy was substantially reduced compared to those of the standard strategy. Worm counts showed that on new strategy paddocks the numbers of trichostrongylid larvae, except Nematodirus spp, were reduced by 50 to 95% compared to standard strategy paddocks. Worm egg counts from the set-stocked weaners were reduced by about 50% on new strategy paddocks from April to October. Weaners grazing the new strategy paddocks grew significantly more clean wool (254 g, P=0.01) and were significantly heavier in October (3.2 kg, P = 0.01) than weaners in the standard strategy paddocks. The improved production was attributable partially to better pasture growth early in winter and partially to reduced parasitism. Conclusion The new strategy is a simple, practical and widely applicable example of the integration of grazing management with strategically timed anthelmintic treatments to reliably reduce trichostrongylid infections in weaners grazing during winter and spring.

Objective To relate trichostrongylid infections acquired by sheep during summer to prevailing weather conditions. Procedure Groups of worm-free ‘tracer’ sheep were put onto pastures, previously contaminated with trichostrongylid eggs, for successive periods of 2 weeks from December to March. After grazing the sheep were housed for 6 weeks. Weekly worm egg counts and worm counts were used to estimate the numbers of worms acquired and related to weather conditions during the grazing period. Results No worm eggs were detected in the faeces of sheep that grazed at the end of January when only 7 mm of rainfall was recorded. At other times rainfall between 12 and 24 mm occurred and strongyle egg counts were generally either 150 eggs per g (epg). Mean counts of 1100 Ostertagia and Trichostrongylus adults gave rise to mean counts of about 350 epg whereas about 6000 Nematodirus spp were associated with mean egg counts of about 200 Nematodirus spp epg. Conclusions Rainfall events during summer determine the numbers of trichostrongylid larvae acquired by sheep in summer but further studies are necessary before the implications for strategic control programs in southern Australia can be fully assessed.

The aim of the present study was to compare the effectiveness of the concentration techniques of flotation-centrifugation with zinc chloride (FZn) (δ = 1.45) with the spontaneous sedimentation (SSed) and the sucrose flotation-centrifugation (FSuc) (δ = 1.2) to recuperate gastrointestinal parasites from camelid fecal samples. The technique with more positive results for the detection of Nematodirus sp., Trichuris sp., strongyle-type eggs and Eimeria macusaniensis oocysts was the FZn. For Trichuris sp. and Eimeria macusaniensis, the higher coverglass counts were detected by FZn procedure. No significant differences were registered among centrifugation flotation techniques for Nematodirus spp. Coverglass count for strongyle-type eggs was significantly higher for FSuc than FZn (p = 0.0005) or SSed (p = 0.0005), being also significantly higher for FZn than for SSed (p = 0.008). FZn is a sensitive technique that allows the recovery of parasite elements with high density and it exerts low osmotic pressure avoiding parasite deformation. Fil: Taglioretti, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Sardella, Norma Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Fugassa, Martín Horacio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina

Background Nematodirus spp. are among the most common nematodes of ruminants worldwide. N. oiratianus and N. spathiger are distributed worldwide as highly prevalent gastrointestinal nematodes, which cause emerging health problems and economic losses. Accurate identification of Nematodirus species is essential to develop effective control strategies for Nematodirus infection in ruminants. Mitochondrial DNA (mtDNA) could provide powerful genetic markers for identifying these closely related species and resolving phylogenetic relationships at different taxonomic levels. Methods In the present study, the complete mitochondrial (mt) genomes of N. oiratianus and N. spathiger from small ruminants in China were obtained using Long-range PCR and sequencing. Results The complete mt genomes of N. oiratianus and N. spathiger were 13,765 bp and 13,519 bp in length, respectively. Both mt genomes were circular and consisted of 36 genes, including 12 genes encoding proteins, 2 genes encoding rRNA, and 22 genes encoding tRNA. Phylogenetic analyses based on the concatenated amino acid sequence data of all 12 protein-coding genes by Bayesian inference (BI), Maximum likelihood (ML) and Maximum parsimony (MP) showed that the two Nematodirus species (Molineidae) were closely related to Dictyocaulidae. Conclusions The availability of the complete mtDNA sequences of N. oiratianus and N. spathiger not only provides new mtDNA sources for a better understanding of nematode mt genomics and phylogeny, but also provides novel and useful genetic markers for studying diagnosis, population genetics and molecular epidemiology of Nematodirus spp. in small ruminants.

The aim of this study was to estimate the occurrence of intestinal parasites in groups of mammals kept in the Warsaw zoological garden (Poland). 71 pools of fecal samples were analyzed using the FLOTAC techniques. 48% of animals were positive and 47% of positivities showed multiple infections. Toxocara cati (71.4%) was found in felines; marsupials were infected with Coccidia (90%). Giardia spp. (24.0%), Blastocystis spp. (12.3%), Iodamoeba spp. (10.0%), Enterobius vermicularis (6.0%) and Entamoeba coli (3.3%) were found in primates. Gastrointestinal strongyles (60.5%) were prevalent in ruminants which resulted positive also to Coccidia (Eimeria spp. = 50.0%), Trichuris spp. (25.0%) and Nematodirus (14.0%). Strongyles (34.0%) were the most frequent parasites in monogastric herbivores, followed by Parascaris equorum (17.0%). None of the animals showed any symptom associated with gastrointestinal parasitic infections. According to our results the need to prevent, diagnose, control, and treat intestinal parasitism trough specific control programs is mandatory for animal welfare in order to limit the spread of parasitic infections in animals and humans.

A study was conducted to evaluate the therapeutic efficacy of doramectin administered intramuscularly at a dose rate of 200 microg/kg to sheep harbouring naturally acquired infections of gastrointestinal nematodes and Oestrus ovis in the southwestern region of France. On day 0, 24 sheep were selected on the basis of positive faecal egg counts (>100 EPG) and positive assessment of O. ovis infection (including positive O. ovis antibody level and positive clinical score). The sheep were randomly allocated to a non-medicated control group (T1) or a doramectin-treated group (T2) of 12 animals each. On day 0, sheep in group T2 received a single intramuscular injection of doramectin (200 microg/kg), whereas those in group T1 received an intramuscular injection of saline solution (sodium chloride, 0.02ml/kg). Individual faecal egg counts were performed on days 0, 1, 2, 3, 4, 5, 6, 7, and 14. Between days 14 and 16, all sheep were slaughtered, and worm and O. ovis burdens were determined. In doramectin-treated sheep, faecal egg counts had decreased to zero by day 4 for all recovered types of nematode eggs: strongyles, Nematodirus sp., Trichuris sp., and Rhabditidae sp. For strongyles, Nematodirus sp., and Rhabditidae, the percentage reductions in faecal egg counts (geometric means) of doramectin-treated sheep, compared to the non-medicated control sheep were 100% from days 4-7. For Trichuris sp., they were 100, 99.7, 99.9, and 100% on days 4, 5, 6, and 7, respectively. On day 14, percentage reductions were 100% for Nematodirus sp. and Rhabditidae, and 99.8 and 99.1% for strongyles and Trichuris sp., respectively. At necropsy, only adult nematodes and mainly first-stage O. ovis larvae were recovered. Doramectin was highly efficacious against the adult stages of Teladorsagia circumcincta (100%), Nematodirus battus (100%), Nematodirus filicollis (99.9%), Oesophagostomum venulosum (99.8%), and Trichuris sp. (99.3%). It was also 100% efficacious against first-stage larvae of O. ovis. No abnormal clinical signs or adverse reactions in any of the sheep treated with doramectin were observed.

Ten 4-month-old female sheep of the Karagouniko dairy breed were used to monitor the seasonal fluctuations of strongyle infections in sheep during the first year of grazing under the traditional production system in the region of Trikala, Greece, where control of nematodes is currently based exclusively on the frequent use of anthelmintics which might contribute to the appearance of anthelmintic resistance. The sheep grazed communal pasture plots and did not receive any anthelmintic treatment during the entire study period. Faecal egg counts (epg), plasma pepsinogen levels, blood values, and genera of parasitic strongyles recovered from coprocultures were recorded monthly. Mean epg for strongyle-type eggs were significantly higher during summer. Mean plasma pepsinogen levels were significantly higher during spring and summer. The genera of parasitic strongyles recovered from the faecal cultures were Haemonchus, Ostertagia, Trichostrongylus, Cooperia, Nematodirus, Oesophagostomum, and Chabertia. The percentages of larvae for Haemonchus, Ostertagia, Cooperia, and Oesophagostomum were significantly higher during winter. The percentages of larvae for Trichostrongylus were significantly higher during summer. During summer, levels of RBC, HGB, and HCT were depressed and levels of MCV, MCH, and MCHC were elevated. Mean epg for strongyle-type eggs had a significant inverse correlation with RBC, HGB, HCT, and positive correlation with MCH, MCHC, and percentages of eosinophils in differential leucocyte counts. The seasonal pattern of infection observed in the present study indicates that it is possible to decrease the number of treatments to one per year, thus, reducing the possibility for the appearance of anthelmintic resistance.

Llamas or South American Camelids (SACs) are increasingly popular in the United States, as a source of fiber, livestock guard, and pack animals. Gastrointestinal parasites have been identified as a major health problems in all classes of livestock including llamas. Currently there are no approved anthelmintics available for use in llamas. In this study, fenbendazole was evaluated for its clinical efficacy in the control of gastrointestinal parasitism in llamas. Twelve, healthy, young adult llamas of both sexes naturally infested with Nematodirus, Strongyloides, Trichuris, and Capillaria were randomly divided into two groups. One group received a single oral dose of fenbendazole paste at 5 mg/kg. The second group received a comparable dose of water as a placebo. Fecal samples were obtained per rectum from each animal prior to administration of either the drug or placebo treatment and weekly thereafter. These samples were analyzed for total fecal egg burden using a modified Wisconsin sugar floatation technique. The fenbendazole treated group had a significant reductions in total fecal egg counts of 95%, 84%, 89% and 76%, respectively, for each week of the four-week sampling period. Nematodirus, Strongyloides, and Trichuris all had significant reductions in egg counts during the study period All animals were observed twice daily during the experiment. All animals remained healthy and showed no adverse effects related to treatment. These results indicate that fenbendazole is a safe and an effective anthelmintic for the treatment of naturally occurring gastrointestinal parasite infestations of Nematodirus, Strongyloides, and Trichuris in llamas. # 2000 Published by Elsevier Science B.V. All rights reserved.

Faecal samples were collected from 348 yaks(Bos poephagus) in and around Gurudogmer Plateau, a cold desert area in North Sikkim, India. The prevalence of gastrointestinal parasitic infection was recorded at 10.05% in both the organized and traditionally managed farms of yak. The pattern of infection was either single (2.58%) or mixed (7.47%) with a faecal egg count range of 100-200 eggs per gram of faeces in positive animals. Among the helminths, Haemonchus spp. infection was predominant (6.89%) followed by Nematodirus spp. (1.72%), Cooperia spp. (1.43%) and Dicrocoelium spp. (0.29%).

The sequence of the second internal transcribed spacer of ribosomal DNA was determined for four species of Nematodirus (Nematodirus rupicaprae, Nematodirus oiratianus, Nematodirus davtiani alpinus and Nematodirus europaeus) from roe deer or alpine chamois. The second internal transcribed spacer of the four species varied in length from 228 to 236 bp, and the G + C contents ranged from 41 to 44%. While no intraspecific sequence variation was detected among multiple samples representing three of the taxa, sequence differences of 5.9-9.7% were detected among the four species, Nematodirus davtiani alpinus and N. rupicaprae were genetically most similar (94.1%), followed by N. oiratianus, N. europaeus and N. rupicaprae (91.1-91.5%), whereas N. oiratianus was genetically most different from N. davtiani alpinus. The interspecific sequence differences were exploited for the delineation of the four species by PCR-based restriction fragment length polymorphism (using two enzymes) and single-strand conformation polymorphism. The results have implications for diagnosis, epidemiology and for studying the systematics of the Nematodirinae.

Using sequences of the ribosomal second internal transcribed spacer (ITS2), PCR primers were designed for the differentiation of the gastrointestinal nematode genera Ostertagia, Cooperia, Nematodirus, Haemonchus and Trichostrongylus. Single eggs or larvae from faeces could be differentiated without previous DNA extraction. Quantification of the PCR result proved to be difficult because the DNA content between eggs from fresh or 24-h-old faeces varied considerably.

Three field trials were conducted in Germany, Slovakia and UK to evaluate the anthelmintic efficacy and productivity responses attributable to treatment of lambs with an intra-ruminal controlled-release capsule which is designed to deliver ivermectin at 0.8 mg/day for 100 days to lambs weighing 20-40 kg at treatment. Sixty Merino Landrace, 60 Valaska or 52 Suffolk cross lambs weighing between 24.0 and 40.0 kg at the time of treatment were used. Lambs were either untreated (or subjected to salvage treatment) or they received an ivermectin controlled-release capsule. Faecal egg and larval counts of various nematodes, body weights and scores of the faecal soiling of the breech area (formation of dags) were determined before treatment and at 28, 56, 84, 98 and 112 days after treatment. Before treatment, faecal strongyle, Nematodirus and Trichuris egg counts and Dictyocaulus filaria larval counts were not significantly different (P > 0.05 or P > 0.1) between groups, but at each point of time thereafter, egg and larval counts of the ivermectin controlled-capsule treated lambs were significantly reduced compared to the untreated controls. Lambs treated with the ivermectin controlled-release capsule gained significantly more weight (10.9, 11.1 or 11.1 kg, respectively) over the 112 days of the trials compared to untreated lambs (8.2, 9.7 or 5.5 kg, respectively). The mean scores of faecal soiling were not different at the start of the trials (P > 0.05 or P > 0.1), but at the end of the trials, the ivermectin controlled-release capsule treated lambs had significantly lower scores of faecal soiling than the controls. # 1999 Elsevier Science B.V. All rights reserved.

Examination of 270 deer (of both sexes and aged from 3 months to 7 years old) belonging to different Egyptian zoo gardens between January and December 1996 revealed the presence of Trichuris, Trichostrongylus, Nematodirus, Strongyloid and Dectyocoulus eggs in 109 out of 270 deer. The highest rate of infestation occurred in winter (59.385) and on the contrary, summer season showed a low rate of infestation (33.59%). Infestation with internal parasites resulted in reduction in total erythrocytic count, haemoglobin concentration and packed cell volume, in addition to higher MCV and lower MCHC indicating macrocytic hypochromic anaemia. Moreover, leucocytosis, neutrophilia and eosinophilia, while lymphopenia were observed. Marked reducation in total serum protein, albumin, calcium, sodium, potassium, chlorides, and iron were noted in infested deer, while blood urea concentraton and the activity of serum enzyme alkaline phosphatase appeared to be elevated in infested deer versus those apparently healthy ones. An improved towards the normal level in previously mentioned parameters was observed after treatment with Albendazole and Fenbendazole drugs.

Moghaddar, N. 2008. Seasonal variation in the incidence of gastro-intestinal nematodes in sheep in Iran. J. Appl. Anim. Res., 34: 153–155. To record the seasonal variations in the incidence of gastro-intestinal nematodes of sheep around Shiraz, Fars Province of Iran, 1114 sheep in different age groups were examined. Adult sheep showed higher (P

Genetic differences among Nematodirus spathiger, Nematodirus filicollis, Nematodirus helvetianus and Nematodirus battus in the nucleotide sequence of the second internal transcribed spacer (ITS-2) of ribosomal DNA ranged from 3.9 to 24.7%. Pairwise comparisons of their ITS-2 sequences indicated that the most genetically similar species were N. spathiger and N. helvetianus. N. battus was the most genetically distinct species, with differences ranging from 22.8 to 24.7% with respect to the other three species. Some of the nucleotide differences among species provided different endonuclease restriction sites that could be used in restriction fragment length polymorphism studies. The ITS-2 sequence data may prove useful in studies of the systematics of molineid nematodes.

The efficacies of pyrethrum marc and of albendazole against experimental sheep gastrointestinal nematode infection were compared. Sheep were infected orally with 10000 larvae (Haemonchus spp. (60.1%), Oesophagostomum spp. (13.9%), Trichostrongylus spp. (13.2%), Cooperia spp. (8.3%), Nematodirus spp. (3.5%), Strongyloides spp. (0.8%) and Ostertagia spp. (0.2%)). Faecal egg count reduction in albendazole-treated sheep was 100% by day 4 following treatment, compared to 37.03%, 31.3%, 38.9% and 51.8% on days 4, 6, 8 and 10 in pyrethrum marc-treated sheep. These reductions were statistically significant on days 8 and 10 post-treatment (p

A study was conducted to investigate reinfection with nematodes in calves following treatment with doramectin or ivermectin administered subcutaneously at a dose rate of 200 micrograms kg-1 of body weight under conditions of natural challenge. Thirty calves were allocated to three groups of 10 calves each based on body weight, sex, breed and pre-treatment faecal egg counts (FEC) after grazing together on a common pasture for three months. Treatments were doramectin, ivermectin and no treatment. Calves were returned to the same pasture for 56 days, placed on dry lot from days 56 to 63 and then necropsied over days 64-66. Faecal egg counts were done at days -1 and 0, then bi-weekly from day 14 to 56 and day 63. Mean FEC in control calves continued to rise throughout the grazing period. Trichostrongyle FEC were significantly (P < 0.05) greater in the control group compared to either treated group at each sample time following treatment. At necropsy, a total geometric mean of 19,847 nematodes per calf was recovered from untreated controls, of which eight genera were identified. The predominant nematode genera were Ostertagia (8749), Nematodirus (3702) and Cooperia (1927). In the ivermectin-treated calves, geometric mean worm burden was similar to that of the untreated controls: A total of 20,349 nematodes per calf was present including the genera Nematodirus (8633), Ostertagia (4700) and Cooperia (1740). In contrast, the geometric mean worm burden in doramectin-treated calves was 12,173, including Ostertagia (4310), Cooperia (1141) and Nematodirus (1667). Doramectin was more effective than ivermectin in protecting calves from reinfection over a 56-day post-treatment grazing period under conditions of natural challenge as measured by accumulated mean worm burdens.

The number of nematode eggs in the faeces was estimated in Polish Wrzosowka sheep, in the spring and autumn of 1993 and again in 1994. The sheep had been naturally infected. The dominant species were Haemonchus contortus and Teladorsagia circumcincta, but Trichostrongylus spp., Cooperia curticei, Nematodirus spp. and Chabertia ovina were also present. Anthelmintics were not used. Egg counts were skewed, with a range of 0–4100 eggs g−1 (EPG); most sheep had egg counts below 100 EPG. Egg counts were approximately four times higher in spring than in autumn. Repeatability values within a season were all significant and positive. The repeatability of egg counts between seasons was estimated from the correlation between the mean transformed value in spring and in autumn, and was 0.52 in 1993 (P < 0.001) and 0.41 in 1994 (P < 0.05). The results show that animals with higher than average values in spring are likely to have higher than average values in autumn, and suggest that similar mechanisms regulated egg counts in both seasons even though egg counts were much lower in autumn.

Summary The pattern of pasture contamination and the influence of some climatic factors on the development of ovine Trichostrongyles have been studied in dry pastures of Castilla-La Mancha (central Spain) during a 3-year period (1986–1988). The main identified genera were Ostertagia and Trichostrongylus, followed by Haemonchus, Cooperia and Nematodirus. Two peaks of pasture contamination were detected: from mid-winter to early-spring and from mid-autumn to early-winter. No significant differences in this pattern were observed during the 3 years except Haemonchus (1986–1988, P < 0.05; 1987–1988, P < 0.001). Seasons differed significantly (spring-autumn, P < 0.05; summer-the rest of the year, P < 0.001). The temperature was negatively correlated with the level of pasture infectivity (except for Trichostrongylus); however, the rainfall was positively correlated with pasture infectivity.

Nematodirosis in lambs Jejunal haemorrhagic syndrome in a heifer Epitheliogenesis imperfecta in a bovine fetus Plant poisoning in cattle and sheep Abomasal emptying defect in a ewe Cholangiocellular carcinoma in a duck These are among matters discussed in the Northern Ireland animal disease surveillance quarterly report for April to June 2013.

The genetic architecture underlying nematode resistance and body weight in Blackface lambs was evaluated comparing genome-wide association (GWA) and regional heritability mapping (RHM) approaches. The traits analysed were faecal egg count (FEC) and immunoglobulin A activity against third-stage larvae from Teladorsagia circumcincta, as indicators of nematode resistance, and body weight in a population of 752 Scottish Blackface lambs, genotyped with the 50k single-nucleotide polymorphism (SNP) chip. FEC for both Nematodirus and Strongyles nematodes (excluding Nematodirus), as well as body weight were collected at approximately 16, 20 and 24 weeks of age. In addition, a weighted average animal effect was estimated for both FEC and body weight traits. After quality control, 44 388 SNPs were available for the GWA analysis and 42 841 for the RHM, which utilises only mapped SNPs. The same fixed effects were used in both analyses: sex, year, management group, litter size and age of dam, with day of birth as covariate. Some genomic regions of interest for both nematode resistance and body weight traits were identified, using both GWA and RHM approaches. For both methods, strong evidence for association was found on chromosome 14 for Nematodirus average animal effect, chromosome 6 for Strongyles FEC at 16 weeks and chromosome 6 for body weight at 16 weeks. Across the entire data set, RHM identified more regions reaching the suggestive level than GWA, suggesting that RHM is capable of capturing some of the variation not detected by GWA analyses.

Winter supplementary feeding of wildlife is controversial because it may promote parasite and disease transmission by host aggregation. We investigated the effect of winter supplemental feeding of Scandinavian moose (Alces alces) on gastrointestinal (GI) parasite infection in two counties of southern Norway by comparing fecal egg counts of moose using, and not using, feeding stations between January 2007 and March 2010. We identified three different GI nematodes based on egg morphology. All three were found in Hedmark county while in Telemark county we found only Trichuris sp. (prevalence 33%). Prevalence of Trichostrongylidae (65%) and Nematodirus sp. (26%) in Hedmark was not affected by feeding station use. However, the probability of infection varied significantly between years sampled (Trichostrongylidae) and age class (Nematodirus sp.). Fecal egg counts (FEC), a proxy for intensity of infection, of Trichostrongylidae were higher in the year when winter weather conditions were more challenging and prevalence was higher, and decreased with increasing body mass. Adult moose had higher FECs than did juvenile moose, and female juveniles had lower abundances than did male juveniles. Use of feeding stations did not affect probability of infection with any of the nematodes or intensity of infection with Trichostrongylidae. We discuss our findings in terms of parasite life histories and recommend that parasitologic surveillance be included in the monitoring of feeding programs.

The aim of this study was to obtain up-to-date information on the presence and distribution of helminths in grazing sheep from the Basilicata region of southern Italy. A cross-sectional coprological survey was conducted on 98 sheep farms and the FLOTAC dual technique was used to detect and count parasitic elements. The most frequent nematodes found were gastrointestinal (GI) strongyles (91.8 %), in particular Haemonchus (76.9 %), Trichostrongylus (91.8 %), Teladorsagia (88.8 %), Cooperia (77.6 %), and Oesophagostomum (72.5 %). They were followed by lungworms (50.0 %), including Muellerius (37.8 %), Neostrongylus (13.3 %), Protostrongylus (4.4 %), Cystocaulus (2 %), and Dictyocaulus (2 %). We also found Trichuris (39.8 %), Nematodirus (24.5 %), Strongyloides (4.1 %), and Skrjabinema (2.0 %). Trematoda were also found with the following prevalence: Calicophoron daubneyi (10.2 %), Dicrocoelium dendriticum (61.2 %), and Fasciola hepatica (1.0 %). Moniezia was found on 35.7 % of farms. Interestingly, the spatial analysis showed clusters for C. daubneyi and D. dendriticum.

We examined the efficacy of an anthelmintic agent (ivermectin, Merck–Agvet) on the parasitic nematodes of free-ranging snowshoe hares (Lepus americanus) during 27 months in southern Manitoba. Marked hares on six 25-ha sites were injected bimonthly with ivermectin (treatment, n = 134) or propylene glycol (control; n = 149) and carcasses were necropsied to determine prevalence and intensity of Obeliscoides cuniculi, Nematodirus triangularis, Trichuris leporis, Dirofilaria scapiceps, and Protostrongylus boughtoni. We supplemented the control sample with hares (n = 175) captured off the study sites and not given propylene glycol. Mean prevalence (percentage of hosts infected) and intensity (number of parasites among infected hosts) of each nematode species decreased after treatment and were 35 – 85% lower than controls after 20–40 days. Treatment significantly reduced prevalence of D. scapiceps and P. boughtoni for about 50 days and of O. cuniculi and N. triangularis for longer periods. Overall intensity of O. cuniculi, N. triangularis, and P. boughtoni was significantly lower in treated than in control hares, and intensity of D. scapiceps was marginally (P

OBJECTIVE To investigate the relative efficacy and safety of the anthelmintic naphthalophos in sheep, either given alone or in combination with benzimidazole (fenbendazole and albendazole) or levamisole anthelmintics. DESIGN A parasitological study using faecal egg count reduction tests, a validating slaughter trial and field safety trials. PROCEDURE Faecal egg count reduction tests were carried out on 13 farms. Naphthalophos and combinations of naphthalophos with levamisole and fenbendazole were included in the drench tests. On one property a controlled efficacy study was carried out to validate faecal egg count reduction test findings. In this trial, sheep were slaughtered 10 days after treatment and the remaining parasites recovered from the gastro-intestinal tract. Safety trials were carried out on eight farms where approximately 50,000 sheep were treated with naphthalophos and albendazole that were tank mixed in the backpack. RESULTS The efficacy of naphthalophos alone in faecal egg count reduction tests ranged from 59 to 98% with one test showing > or = 95% reduction. The efficacy of naphthalophos and levamisole ranged from 74 to 100%, with 5 farms showing > or = 95% reduction. The efficacy of naphthalophos and fenbendazole ranged between 88 and 100% with > or = 95% reduction achieved on 10 farms. The controlled efficacy study showed a good correlation between the faecal egg count reduction tests and numbers of parasites recovered, except for Nematodirus where the faecal egg count reduction test overestimated efficacy. The mortality rate in the safety trials was 0.05%, with most fatalities occurring on one farm. CONCLUSION The combination of naphthalophos and fenbendazole was more effective than a combination of naphthalophos and levamisole, and will provide a sufficiently safe drench rotation option.

From July 1990 to February 1991, nematode numbers in free-ranging snowshoe hares (Lepus americanus) at Kluane Lake, southwestern Yukon, Canada, were manipulated by subcutaneous injection (0.4 mg/kg) of ivermectin. Three field experiments were conducted to determine the degree of helminth loss associated with a single administration of ivermectin; the length of time that ivermectin was effective in reducing worm numbers; and the effect of repeated ivermectin administration in reducing worm numbers. Numbers of the nematodes, Protostrongylus boughtoni and Nematodirus triangularis were reduced by approximately 80% 2 wk after treatment with a single dose of ivermectin, and were still significantly lower than controls at 4 wk. However, beyond 2 wk, ivermectin did not affect the rate of acquisition of new worms of either species. All treated groups contained one or more hares in which numbers of P. boughtoni and N. triangularis were not reduced. In addition, ivermectin had no effect on numbers of Trichuris leporis or Passalurus sp. Overall, ivermectin was not as effective against the nematodes of free-ranging hares as has been reported for nematodes of domestic and laboratory animals.

Gastrointestinal and bronchopulmonary nematode infections and the efficacy of netobimin (Hapasil) were analyzed by way of fecal examination in 10 female mouflons (Ovis musimon), in central Spain, February 1993. Before treatment all 10 mouflons had Trichostrongylus axei, Teladorsagia circumcincta and Marshallagia spp.; sic had Nematodirus spp., two had Trichuris sp., one had Capillaria sp., seven had bronchopulmonary Dictyocaulus filaria and 10 mouflons had protostrongylid lungworms (Muellerius capillaris, Protostrongylus rufescens, Cystocaulus ocreatus or Neostrongylus linearis). Netobimin (7.5 mg/kg) was 100% effective against T. axei, T. circumcincta, Marshallagia spp., and D. filaria infections whereas one animal continued eliminating Nematodirus spp. eggs. The drug also was effective against Capillaria spp. but not against Trichuris spp. or protostrongylid infections.

We tested the hypothesis that helminth parasitism is demographically significant to a noncyclic population of snowshoe hares (Lepus americanus) near the species' geographic boundary in central Wisconsin (U.S.A.). During November 1988 to December 1991, we injected 93 individuals (≥760 g, aged ≥2 months) with anthelmintics: Ivermectin for nematode and Droncit for cestode infections. We injected 98 control hares with propylene glycol, the common vehicle for both drugs. All treated and control hares were radio-collared with mortality-sensing transmitters and monitored daily to weekly from the ground or air. Prevalence and intensity of lungworms (Protostrongylus boughtoni), intestinal worms (Nematodirus triangularis), and stomach worms (Obeliscoides cuniculi) were markedly reduced by Ivermectin treatment. No other nematodes were found to be present. Treatment with Droncit to remove intestinal cestodes was apparently unnecessary, as prevalence among necropsied untreated hares and controls was just 10%. We compared body-condition indices (mass changes, response to trap stress, and bone-marrow fat), reproduction (pregnancy rate and litter size), home-range sizes, and time-specific survival rates of anthelmintic-treated versus control hares. None of these demographic variables differed significantly between treated and control cohorts, nor was there any evidence that parasitism increased the risk of death from predation, which was the proximate cause of 96% of all natural mortalities. We conclude that helminth parasitism played no detectable role in the dynamics of this Wisconsin snowshoe hare population.

A cross sectional, coprological survey on gastrointestinal (GI) parasites of captive mammals in the Dehiwala National Zoological Gardens was carried out in 2014. Fresh faecal samples from all the mammal species belonging to nine orders: Primates, Carnivora, Perissodactyla, Artiodactyla, Proboscidea, Erinaceomorpha, Lagomorpha, Rodentia and Diprotodontia were analyzed. Intensity of parasite infections was determined using the McMaster technique. Of the 70 samples, 44 (62.9%) were positive for one or more GI parasites. A total of 13 types of GI parasite eggs, cysts and/or oocysts of Trichuris sp., Strongyloides sp., Toxocara sp., Spirometra sp., Moniezia sp., Nematodirus sp., Giardia sp., Blastocystis sp., Balantidium sp., Entamoeba spp., strongyle type eggs, hookworm, and coccidian oocyts were observed. The most common stage was strongyle type egg (17.1%) followed by cysts of Entamoeba spp. (14.3%). Of the infected individuals, 25% had mixed infections. A higher prevalence of helminths (81.8%) compared to protozoans (47.7%) was observed but this difference was not statistically significant (Chi square test; p>0.05). There was no significant difference in the prevalence of infection among the captive bred, imported or wild caught individuals (Chi square test; p>0.05). Mammals of seven orders were infected with GI parasites but lagomorphs and diprotodonts did not have any parasites. Among the herbivores, strongyle type, Moneizia, Entamoeba and coccidian infections were common while Nematodirus sp. in a porcupine and Spirometra sp. in a flying squirrel were rare. Common parasites of carnivores were, Toxocara and Entamoeba but Blastocystis sp. in coati was a rare infection. Trichuris and Giardia infections were common in Primates. High worm burden was evidenced in silver leaf monkey, Hamadryas baboon, African lion, black rhino, pony, porcupine and flying squirrel. Although regular deworming is carried out, results of this survey highlight the importance of faecal analysis before administering deworming and applying a more targeted approach to manage the pathogenic species. This study provides baseline data on the GI parasites of all the mammal orders at Dehiwala Zoological Gardens.

Seasonal population trends of helminth parasites of growing lambs were investigated over 4 years. Successive worm-free lambs were grazed together with untreated lambs for 20–30 days and then slaughtered for helminth counts 2 weeks after their removal from pasture. Likewise untreated lambs from the same flock were slaughtered from 2 to 15 months of age for worm counts in the same way as tracer lambs. The predominant parasites were Haemonchus, Nematodirus and Trichostrongylus. Haemonchus contortus was found to be of major importance and the flock aquired massive worm burdens from summer to mid-autumn. Minimum burdens were seen from winter to early spring and maximum L4 stages were found from mid-autumn to early winter. Nematodirus burdens increased from December with a peak in late summer and then decreased to low values. Maximum larval availability was in autumn to early winter. Trichostrongylus (mainly T. colubriformis ) populations increased in autumn and peaked in June–July, while the highest larval availability was in autumn. The minor genera recovered were Ostertagia, Cooperia, Trichuris, Oesophagostomum and Moniezia. Dictyocaulus, Chabertia and Teladorsagia were noted occasionally and liver flukes were not detected. No important and pathogenic numbers of L4 stages were seen and all predominant species were able to survive over summer or winter in pasture.

The nematocidal effect of doramectin was assessed by subcutaneous injection of 200 micrograms/kg (single dosage) in cattle with naturally acquired gastrointestinal nematode infection in Japan. This study consisted of two experiments. In experiment 1, animals were randomly divided into a doramectin group (n = 21) and a non-treated control group (n = 21) by fecal egg count. In experiment 2, another group of ivermectin treatment (n = 12) was prepared in addition to doramectin (n = 23) and control (n = 10) groups, by random assignment as in study 1. After doramectin or ivermectin treatment, the egg count/5 g of feces was measured by the sucrose centrifugal flotation method at intervals of 7 days until Day 21 in experiment 1 and at Days 7, 14, 21, 35, 42, 49 and 63 in experiment 2. Coproculture was also carried out using some of the fecal samples. In the 2 doramectin-treated groups, 96.1%-100% egg reduction rates were obtained for Haemonchus, Cooperia, Mecistocirrus, Trichostrongylus, Ostertagia, Bunostomum, Strongyloides and Trichuris from the 7th day until the 49th day after treatment. Thus doramectin was confirmed to be highly effective against those species of adult nematoda. The effect against Mecistocirrus has not been previously determined. The nematocidal effect against Nematodirus was lower (egg reduction rate approximately 50%) than other species. No adverse reactions to treatment were seen in any animal during either study.

Out of various diseases affecting sheep, parasitic gastroenteritis caused by gastro-intestinal nematodes, mainly Haemonchus contortus, is very important for the sheep in India and is responsible for high mortality and morbidity (Yadav, 1997). The gastrointestinal nematodes of sheep include H. contortus, Telodorsagia circumcinta, Trichostrongylus axei, Nematodirus spp. and Cooperia spp. The proportions of each of these nematodes in sheep populations vary according to geographic location. H. contortus and T circumcincta represent most of the parasite burdens seen in sheep, with H. contortus being present in highest numbers. Anthelmintic resistance is present in all of these parasites, but the prevalence is highest for H. contortus, making it the most economically important gastrointestinal nematodes of sheep (Fleming et al., 2006).

Goats, called “the cow of the poor”, are the livestock species with the most significant population growth worldwide in recent years. Gastrointestinal parasitism constitutes one of the main constraints to its outdoor and extensive breeding in temperate and tropical countries. Despite a Creole goat population of nearly 4 million heads, local reports on parasitological prevalence are scarce, and while Fasciola hepatica infection is spread all over Argentina, the goat is usually neglected as a reservoir and economic losses are not considered. To evaluate gastrointestinal parasitism prevalence and associations between parasite genera and species, with emphasis on fascioliasis, Creole goats from the plateau and Andean regions from western Argentina were investigated by coprological techniques, and associations were statistically assessed. Eighty-five percent (85%) of the animals harbored one or more parasite types, while 46% showed mixed infections. Significant positive associations between F. hepatica + Strongyle eggs, Eimeria sp. + Nematodirus sp. andNematodirus sp. + Trichuris oviswere detected. Further studies are required to define the causality of these associations and their relevance in epidemiology. F. hepaticais rarely considered as goat parasite in the country, but a 33% prevalence poses an interrogation on the role goats play on the transmission and dissemination of this zoonotic trematode. As cabras, nomeadas como “a vaca dos pobres”, são as espécies de gado com o crescimento populacional mais significativo nos últimos anos em todo o mundo. O parasitismo gastrintestinal constitui uma das principais limitações à sua criação extensiva em clima temperado e tropical. Na Argentina, apesar de uma população de caprinos crioulos de cerca de quatro milhões de cabeças, são escassos os relatórios locais de prevalências parasitológicas. Embora a infecção porFasciola hepatica esteja espalhada em todo o país, as cabras são geralmente negligenciadas como um reservatório, e as perdas econômicas não são consideradas. Para avaliar a prevalência do parasitismo gastrintestinal e associações entre os gêneros e espécies de parasitos, com ênfase na fasciolose, caprinos crioulos da região andina e do planalto do oeste de Argentina foram avaliados por meio de técnicas coprológicas. Oitenta e cinco por cento dos animais hospedaram um ou mais tipos de parasitos, enquanto 46% hospedaram infecções mistas. Foram encontradas associações significativas entre F. hepatica+ ovos de estrongilídeos, Eimeria sp. +Nematodirus sp. e Nematodirus sp. +Trichuris ovis. Mais estudos são necessários para definir a causalidade dessas associações e sua relevância na epidemiologia. Raramente F. hepaticaé considerada como um parasito de cabra no país, mas uma prevalência de 33% suscita uma interrogação sobre o papel dos caprinos na transmissão e disseminação desse trematódeo zoonótico.