Helminths of roe deer (Capreolus capreolus) in the Middle Black Sea Region of Turkey

Fifteen roe deer were examined at necropsy from Northern Turkey in the period 2006-2010 for the helminth infections. Totally 6470 helminth specimens were collected and identified by morphological criteria. Twenty-five helminth species were identified (1 of the Class Trematoda, 1 of Cestoda and 23 of Nematoda). Dicrocoelium dendriticum (Prevalence 20%) was found in liver. Cysticercus tenuicollis (6.6%) was found in mesentery. Haemonchus contortus (53.3%), Ostertagia leptospicularis (73.3%), O. leptospicularis (minor morph: kolchida) (53.3%), Ostertagia ostertagi (26.6%), Spiculopteragia spiculoptera (66.6%), S. spiculoptera (minor morph: mathevossiani) (6.6%), Teladorsagia circumcincta (40.0%), T. circumcincta (minor morph: davtiani) (6.6%), T. circumcincta (minor morph: trifurcata) (6.6%), Trichostrongylus axei (66.6%) were found in abomasum. Trichostrongylus andreevi (6.6%), T. colubriformis (6.6%), T. longispicularis (26.6%), T. vitrinus (40.0%), T. capricola (6.6%), Cooperia oncophora (26.6%), C. punctata (6.6%), Nematodirus filicollis (66.6%), and Capillaria bovis (26.6%) were found in small intestine. Oesophagostomum venulosum (46.6%), Chabertia ovina (26.6%), and Trichuris ovis (13.3%) were found in large intestine. Dictyocaulus capreolus (6.6%) was found in lungs.     

The comparative efficacy of oxfendazole administered as bolus and suspension to naturally infected sheep in Greece

In a flock of 20 ewes naturally infected with those parasites of sheep most common in Greece, and kept indoors during the whole trial, oxfendazole at the dose rate of approximately 2.9 and 2.8 mg/kg body-weight was tested as a 4 g bolus containing 112 mg active ingredient and a 2.265% suspension. The evaluation of its efficacy was based on the necropsy findings which were also supported by faecal egg counts. No differences in efficacy were noticed between the two formulations of the drug. Both bolus and suspension proved to be 100% effective against Haemonchus contortus, Ostertagia circumcincta, Trichostrongylus axei, T. colubriformis and Chabertia ovina. The efficacy against Cooperia oncophora, Nematodirus spathiger, Bunostomum trigonocephalum, Oesophagostomum columbianum and Moniezia expansa could not be evaluated, because these species, though not found in any of the treated animals, were found in fewer than three controls.     

First sign in Italy of Nematodirus roscidus, Apteragia quadrispiculata and Ostertagia drozdzi, found in Dama dama

The authors refer the first report in Italy of Nematodirus roscidus Railliet, 1911, Apteragia quadrispiculata Jansen, 1958 and Ostertagia drozdzi Jancev, 1977 from Dama dama. In fallow deer they found also: Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Spiculopteragia asymmetrica, Skrjabinagia arctica, Oesophagostomum venulosum, Trichuris ovis. Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus and Skrjabinagia arctica were not found before in Dama dama in Italy.     

Efficacy of p-Toluoyl chloride phenylhydrazone against gastrointestinal helminths in ovines.

A new anthelmintic candidate, p-toluoyl chloride phenlylhydrazone, was administered to lambs in a paste formulation. The efficacy of this drug was determined at dose rates of 20, 30, 40, and 50 mg of active ingredient per kilogram of body weight. Helminths expelled by these dosages included Haemonchus contortus, Ostertagia circumcicta, Trichostrongylus colubriformis, T. axei, Nematodirus filicollis, Cooperia curticei, Strongyloides papillosus, Oesophagostomum columbianum, Bunostomum trigoncephalum, Chabertia ovina, Moniezia expansa, and M. benedeni.     

Differences in the second internal transcribed spacer (ITS-2) of eight species of gastrointestinal nematodes of ruminants.

Genetic differences in the nucleotide sequence of the second internal transcribed spacers (ITS-2) among Trichostrongylus axei, Trichostrongylus colubriformis, Ostertagia ostertagi, Cooperia oncophora, Cooperia punctata, Nematodirus helvetianus, Nematodirus filicollis, and Haemonchus contortus are described. The ITS-2 sequences of the 8 species ranged between 230 and 241 base pairs in length. Sequence similarities between the different genera varied between 60% and 80%. Identities between the different species within a genus varied between 99% for C. oncophora and C. punctata, 95% for T. axei and T. colubriformis, and 89% for N. helvetianus and N. filicollis. The ITS-2 sequences proved to be useful for species differentiation. Except for the species of Cooperia (2.07% intraspecific variations for C. oncophora and 0.83% for C. punctata) the degree of intraspecific variations (N. filicollis 0.85%, T. colubriformis 1.26%, T. axei 1.27%, H. contortus 2.60%, O. ostertagi, and N. helvetianus no variation) was markedly lower than the interspecific variations allowing a reliable differentiation within the ITS-2 region between single species.     

Abomasal and small intestinal nematodes from captive gazelles in Spain

The abomasal and small intestinal helminth fauna of three species of captive gazelles (Gazella dama mhorr, G. cuvieri and G. dorcas neglecta) kept in captivity in Almería (southeast Spain) have been studied, and the following species were identified: Nematodirus spathiger, N. filicollis, N. helvetianus, Camelostrongylus mentulatus, Trichostrongylus vitrinus, T. probolurus, T. colubriformis, Ostertagia ostertagi, O. harrisi, Teladorsagia (Ostertagia) circumcincta, and T. (Ostertagia) davtiani. Camelostrongylus mentulatus and N. spathiger were the most prevalent and abundant parasites. Ostertagia ostertagi, O. harrisi, N. helvetianus, and T. (Ostertagia) davtiani were identified for the first time in the genus Gazella. In addition, O. harrisi and Trichostrongylus probolurus are new records for Spain.     

Studies on the presence and release of proteolytic enzymes (proteinases) in gastro-intestinal nematodes of ruminants

The proteolytic activity of worm homogenates prepared from the third stage larval (L3) and adult stages of the ovine gastro-intestinal nematodes, Nematodirus battus, Ostertagia circumcincta, Trichostrongylus colubriformis, Trichostrongylus vitrinus and Haemonchus contortus, and the rodent intestinal nematode, Nippostrongylus brasiliensis, has been examined using the protein substrates azocasein, azocoll and elastin-orcein. Activity detected in third stage larvae was usually higher than that observed in the adult. Species and stage differences were demonstrated. The in vitro release of proteolytic activity, detected using protein substrates and specific low molecular weight peptide substrates, was, similarly, shown to exhibit a degree of species and stage specificity. Acetylcholinesterase and lactate dehydrogenase activities were determined as reference 'secretory' and 'non-secretory' enzymes, respectively. Three separate peaks of 'tryptic' activity were detected following anion-exchange chromatography of culture fluids derived from adult Ostertagia circumcincta. These peaks could be ascribed to different proteinase classes on the basis of inhibitor sensitivity.     

Microecological characterization of parasitic nematoda present in goats of arid zones of Venezuela

Goats from the Venezuelan northern arid zones were found infested by the following nematodes: Haemonchus contortus, Trichostrongylus axei, T. colubriformis, Cooperia curticei, Oesophagostomum columbianum, Skrjabinema ovis y Trichuris globulosa. The Shannon-Weaver index of diversity values oscillated between 0.045 and 1.73 bits (means = 1.16 +/- 0.24 bits). The maximum value of montly diversity ranged from 1 to 2.80 bits (means = 2.49 +/- 0.28 bits) and the equitability ranged from 0.045 to 0.67 (means = 0.44 +/- 0.09). Parasitic associations were found among 1) T. axei, T. colubriformis and H. contortus, 2) T. colubriformis, H. contortus and O. columbianum and 3) T. colubriformis, S. ovis and T. globulosa. The above results suggest that in months when the diversity index is close to the maximum value and the equitability index is near unity, wide spectrum antihelmintic treatment should be used for poly-parasitized animals.     

Biomorphology of gastrointestinal nematodes of small ruminants

Under the term gastrointestinal nematodes are included numerous parasites species of livestock belonging to the families Strongyloididae (Strongyloides), Strongylidae (Chabertia, Oesophagostomum) Trichostrongylidae (Trichostrongylus, Ostertagia, Teladorsagia, Cooperia, Marshallagia), Molineidae (Nematodirus), Ancylostomatidae (Bunostomum) and Trichuridae (Trichuris). This paper reviews the biomorphology aspects of these parasites as well as the controversy by the taxonomists in the classifications.     

Examination of gastrointestinal helminth in livestock grazing in grassland of Bangladesh

To determine association of grassland with parasitic diseases of livestock in Bangladesh, the 'Tracer' animals (two cow calves and two goats) were released for a month in a grassland used for communal grazing of livestock near school premise in Kanthal, Trishal, Mymensingh, Bangladesh. After slaughtering of the tracer animals, their gastrointestinal tract examination revealed six species of nematode and one cestode. The nematode species were Haemonchus contortus, Trichostrongylus axei, Mecistocirrus digitatus, Oesophagostomum spp., Trichuris spp. and Bunostomum sp. The cestode was one of the genus Moniezia. With this preliminary study, grasslands are thought to be one of the main sources of gastrointestinal parasitic diseases of livestock in Bangladesh.     

Nematoda: Aerobic respiratory pathways of adult parasitic species

Aerobic respiratory pathways have been compared in adult parasitic nematodes, including Trichostrongylus colubriformis, Nippostrongylus brasiliensis, Ostertagia ostertagi, Cooperia oncophora, Haemonchus contortus, Oesophagostomum venulosum, Chabertia ovina, Dictyocaulus filaria, Dictyocaulus viviparus, and Ascaridia galli. Respiration was measured in both whole worm or tissue homogenates and isolated mitochondrial fractions, and delineated into the mammalian type or alternative respiratory pathways on the basis of their inhibition by antimycin A. The alternative, antimycin A-insensitive respiratory pathway was of comparable activity in all parasitic nematodes studied, irrespective of the body diameter or habitat of the worm. The mammalian-type, antimycin A-sensitive respiratory pathway showed variations; the extent of this pathway correlated with both the body diameter and habitat of the worm, being greater in thinner worms and those worms whose habitat is supposedly more aerobic.     

Gastro-intestinal helminths in white-tailed deer (Odocoileus virginianus) of Illinois.

Two deer populations, one in northern Illinois the other in southern Illinois, were examined by necropsy (n = 44 and 40 respectively) for helminth parasites of the gastro-intestinal tract and abdominal cavity. Both herds were parasitized by Apteragia odocoilei, Haemonchus contortus, Gongylonema pulchrum, Setaria yehi, Trichuris ovis, and Moniezia benedeni. Nematodirus sp. was found only in deer of northern Illinois. Ostertagia mossi, Capillaria sp., Cooperia sp., and Oesophagostomum sp. were found only in deer of southern Illinois.     

A comparison of superoxide dismutase (SOD, EC:1.15.1.1) distribution in gastro-intestinal nematodes.

An examination of the distribution of superoxide dismutase (SOD) activities in whole worm homogenates from six gastro-intestinal nematodes, at different life-cycle stages, demonstrated that the third larval stages of each species contained notably more activity than the corresponding adults. Significant SOD activities were detected in culture fluids following in vitro maintenance of third and fourth larval stage and adult Trichostrongylus vitrinus and Teladorsagia circumcincta (formerly Ostertagia circumcincta). Marked interspecies variation was observed when SOD isoenzyme profiles of adult and third larval stage Nippostrongylus brasiliensis, Trichostrongylus vitrinus, Teladorsagia circumcincta and Haemonchus contortus were compared. In addition, SOD activity and isoenzyme polymorphism were greater in Nippostrongylus brasiliensis harvested from primed rats compared to parasites recovered from naive rats.     

Effect of genetic type, lactation and management on helminth infection of ewes in an intensive grazing system on irrigated pasture.

A survey of helminth infection was conducted in a flock of 290 ewes distributed into Romanov (R), Merinos d'Arles (M) and Romanov x Merinos (R x M) genetic types, grazing irrigated pasture in the south of France. Faecal egg and larval counts were done seven times per year from 1981 to 1984 on homogeneous groups of ewes and then individually once to four times every autumn from 1985 to 1988. Helminth fauna was diverse and more abundant during autumn. High levels of strongyle infection occurred in the ewes that remained on the same irrigated pastures during summer. Moving to Alpian pastures during the summer lowered autumnal infection. Significant differences between genotypes in intensity of infection were observed in the order R > R x M > M for strongyles (Teladorsagia circumcincta and/or Trichostrongylus vitrinus, Chabertia ovina and/or Oesophagostomum venulosum, Nematodirus spp.), Moniezia spp. and Dictyocaulus filaria. The hierarchy was reversed for Fasciola hepatica infection and not consistent from one year to another for protostrongylid infections. The effect of lactation intensity on the postparturient rise was studied by equilibrating number of ewes according to reproductive status (zero, one or two lambs in lactation). Merino ewes with two lambs in lactation, as well as primiparous Romanov ewes, had significantly higher strongyle infections than the others. The repeatabilities of the larval and egg counts between the four trial years were 0.24, 0.23 and 0.16, respectively, for protostrongyles, Nematodirus and strongyles, with higher intra-annual values for protostrongyles and inconsistently significant results for strongyles due to the presence of several species.     

Titration of subcutaneously administered eprinomectin against mature and immature nematodes in cattle.

Eprinomectin has been approved for use as a topically applied endectocide for beef and dairy cattle. To determine if eprinomectin has utility as an injectable anthelmintic, it was titrated at 0.05, 0.1, and 0.2 mg/kg s.c. against adult (Trial 1) and at 0.05, 0.1, 0.14, and 0.2 mg/kg s.c. against immature (Trial 2) stages of lung and gastrointestinal nematodes in cattle. In Trial 1, every dose of subcutaneously delivered eprinomectin showed maximal or near-maximal (> or = 99%) efficacy against Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei, T colubriformis, Cooperia punctata, Nematodirus helvetianus, Oesophagostomum radiatum, and Dictyocaulus viviparus. Adult C. oncophora was the only exception. However, even against this species, the lowest dose of 0.05 mg/kg showed 93% efficacy, and the efficacious dose necessary to kill 95% (ED95) of adults was 0.056 mg/kg. In Trial 2, every dose of subcutaneously delivered eprinomectin showed maximal or near-maximal (> or = 99%) efficacy against the immature stages of all of the above species of endoparasites. As a result, ED95 values could not be calculated. Consequently, the exquisite potency against endoparasites through parenteral administration suggests that eprinomectin may also have potential utility as an injectable product for cattle.     

In vitro variation of glycogen content in three sheep nematodes.

In vitro variation of glycogen content under aerobic conditions was measured on fresh weight basis in 3 sheep nematodes inhabiting different niches; Haemonchus contortus, Oesophagostomum columbianum and Trichuris ovis. The parasites were saparated into species and then sexes and starved for varying periods of time up to 24 h in glucose-free physiological saline. The differences between females and males and among the species with respect to glycogen content and its rate of change with time are discussed.     

Toxicity of Bacillus thuringiensis to parasitic and free-living life-stages of nematode parasites of livestock

A collection of Bacillus thuringiensis (Bt) strains (Bts) were screened for activity against the free-living larval stages of nematode parasites of livestock. Two strains were identified with significant activity in inhibiting larval development of Haemonchus contortus, Trichostrongylus colubriformis and Ostertagia circumcincta. These strains were also toxic to the adult parasitic stages of these nematode species in vitro. Adult H. contortus and O. circumcincta showed complete cessation of movement within 2 and 4 days, respectively. Trichostrongylus colubriformis adults were less affected, however, movement was still significantly reduced compared with controls. The in vitro activity against the larval stages was of a magnitude similar to or greater than that seen with the anthelmintic drugs thiabendazole and levamisole. N-terminal amino acid sequencing indicated that the two Bts contained either Cry5A and Cry5B proteins, or a Cry13 protein, and the presence of the corresponding cry5A, cry5B and cry13 genes was confirmed by PCR and sequencing. Bacillus thuringiensis spore-crystal suspensions exposed to acidic pH conditions (pH相似文献   

Effects of season and physical condition on the gastrointestinal helminth community of white-tailed deer from the Texas Edwards Plateau

Eighty-six adult female white-tailed deer, Odocoileus virginianus (Zimmermann), collected over a 12-mo period in the Texas Edwards Plateau, harbored six species of nematodes (Haemonchus contortus, Gongylonema pulchrum, Oesophagostomum venulosum, Ostertagia ostertagi, Cooperia sp., and Apteragia odocoilei), and two cestodes (Moniezia sp. and Taenia hydatigena). The patterns of distribution of the three common species of gastrointestinal helminths (H. contortus, O. venulosum, and G. pulchrum) were overdispersed. When analyzed for the main and interactive effects of the extrinsic and intrinsic variables of season and physical condition, respectively, aggregated abundances in H. contortus and O. venulosum appeared to result from the main effect of seasonal changes operating over the collective populations of these two species rather than from the intrinsic factor of physical condition operating within selected subpopulations. Abomasal parasite counts do not appear to be a useful index for monitoring herd condition of white-tailed deer from this geographic region.     

Metazoan-protozoan parasite co-infections and host body weight in St Kilda Soay sheep

For hundreds of years, the unmanaged Soay sheep population on St Kilda has survived despite enduring presumably deleterious co-infections of helminth, protozoan and arthropod parasites and intermittent periods of starvation. Important parasite taxa in young Soay sheep are strongyles (Trichostrongylus axei, Trichostrongylus vitrinus and Teladorsagia circumcincta), coccidia (11 Eimeria species) and keds (Melophagus ovinus) and in older animals, Teladorsagia circumcincta. In this research, associations between the intensity of different parasite taxa were investigated. Secondly, the intensities of different parasite taxa were tested for associations with variation in host weight, which is itself a determinant of over-winter survival in the host population. In lambs, the intensity of strongyle eggs was positively correlated with that of Nematodirus spp. eggs, while in yearlings and adults strongyle eggs and coccidia oocysts were positively correlated. In lambs and yearlings, of the parasite taxa tested, only strongyle eggs were significantly and negatively associated with host weight. However, in adult hosts, strongyles and coccidia were independently and negatively associated with host weight. These results are consistent with the idea that strongyles and coccidia are exerting independent selection on Soay sheep.     

Resistance of field isolates of Trichostrongylus colubriformis and Ostertagia circumcincta to ivermectin.

Twelve Romney lambs and 10 Angora goats were infected with 7000 infective third-stage larvae (89% Trichostrongylus, 11% Ostertagia) collected from goats suspected of harbouring ivermectin-resistant nematodes. On 28 days p.i., the lambs and goats were divided into treatment and control groups of six and five animals, respectively. The animals in the treatment groups were treated with ivermectin (0.2 mg/kg) and necropsied 35 days p.i. Faecal egg counts were estimated on days 28 and 35 p.i. and larval development assays (LDAs) were conducted on 22, 24, 26, 28, 30, 32, 34 and 35 days p.i. The ivermectin treatment reduced Trichostronglus colubriformis burdens by 39% and 13% and Ostertagia circumcincta by 33% and 0% in lambs and goats, respectively. When compared with a susceptible strain, the LDAs indicated a resistance factor before treatment in lambs for T. colubriformis of 2.6 and 1.5 with ivermectin and avermectin B2, respectively, which rose to 3.4 and 2.0 after treatment. The LD50 values of the two control groups were relatively constant throughout the experiment. Prior to ivermectin treatment the LD50 values of the treated groups were similar (P > 0.05) to the control groups but following ivermectin treatment their LD50 values increased steadily until the animals were killed on 35 days p.i. The LD50 values for ivermectin and avermectin B2 of sheep were always slightly higher and significantly different (P < 0.01) than those of goats indicating a host effect on this parameter. The greater reduction in worm counts in goats suggests a difference in the efficacy of ivermectin between lambs and goats. This is the first confirmed report of ivermectin resistance in a field strain of T. colubriformis.