studies on haemonchus contortus. iv. the effect of trichostrongylus axei and ostertagia circumcincta on challenge with h. contortus.worm-free merino yearlings were dosed with either a mixture of infective larvae of trichostrongylus axei and ostertagia circumcincta or with o. circumcincta only, and challenged 90-93 days later with infective larvae of haemonchus contortus. neither of these methods protected sheep against challenged and slight protection was afforded sheep predosed with t. axei and o. circumcincta and challenged with a trickle dose of h. contortus.19817345390
seasonal changes in the structure of nematode populations of cattle in new south wales in relation to inhibited larval development.pasture plots in 3 climatic regions were contaminated with worm eggs of ostertagia ostertagi, trichostrongylus axei, haemonchus spp and cooperia spp in the autumn, winter and spring. successive pairs of parasite-free calves were grazed on the plots for 7 to 10 days at 4-week intervals and then killed for worm counts 14 days after their removal from pasture. on the northern tablelands of new south wales, irrespective of the season of pasture contamination, the degree of inhibition of o. ostertagi ...19807436895
critical tests of new benzothiazole anthelmintic tioxidazole in the horse.the basic-dose confirmation tests of tioxidazole for removal of susceptible populations of gastrointestinal parasites of the horse were made in 10 naturally infected horses, using the critical test method (experiment a). a single dose of toxidazole, given at the rate of 11 mg/kg of body weight, was administered to 5 horses by stomach tube and to 5 horses by mixing the drug with the daily grain ration. in the 5 horses given the drug by stomach tube, aggregate average removals were 90% or more for ...19807447131
studies on haemonchus contortus. iii. titration of trichostrongylus axei and explusion of h. contortus.groups of merino weaners were dosed with infective larvae of trichostrongylus axei in numbers ranging from 20 000-50 000 and challenged 3 months later with 50 000 infective larvae of haemonchus contortus. when the dose of infective larvae of t. axei was given on day 0 and the balance on day + 14, efficacy against h. contortus was > 60% in > 60% of sheep (p < 0, 1). a single dose of 40 000 or 50 000 infective larvae of t. axei was > 80% effective against h. contortus in > 80% of sheep (p < 0, 01) ...19807454233
parasitic infection of camelus dromedarius from iran.25 intestinal tract, 30 oesophagus and respiratory organs and 47 liver of arabian camel were examined. 35 species of nematodes two species of cestodes one immature trematode one cestodes larvae, one diptera larvae, one microfilaria of lung worm and two external parasites were found. this is a first report of helminths in camel from iran. the nematodes: physocephalus sexalatus, ascarops strongylina, haemonchus contortus, cooperia punctata, nematodirus oratianus, nematodirella longissimespiculata, ...19807460130
survival and development of larvae of the common nematodes of ruminants after long-term cryopreservation and investigation of different routes of infestation.exsheathed infective larvae (l3) of 16 species of nematodes were tested for infectivity in either sheep or cattle after they had been frozen and stored in 0,09% nacl solution in the gas phase of liquid nitrogen for periods of up to 59 months. a mean of greater than 90% of the l3 of haemonchus contortus, ostertagia circumcincta, trichostrongylus axei, trichostrongylus colubriformis, nematodirus spathiger, oesophagostomum columbianum and chabertia ovina of sheep and haemonchus placei, ostertagia o ...19807465164
efficacy of moxidectin pour-on against nematode infections in cattle.three groups of eight calves, naturally infected with gastrointestinal nematodes and artificially infected with dictyocaulus viviparus were used to evaluate the efficacy of moxidectin pour-on at dose rates of 0.35 mg/kg and 0.5 mg/kg bodyweight. with both doses the efficacy was 100 per cent against adult d viviparus, trichostrongylus axei, ostertagia species and nematodirus helvetianus. it was more than 99 per cent against ostertagia and nematodirus species fourth stage larvae. a small number of ...19957571270
comparative effects of nematode infection on bos taurus and bos indicus crossbred calves grazing on argentina's western pampas.breed differences in resistance or tolerance to naturally acquired gastrointestinal nematodes were compared between aberdeen angus (aa) and santa gertrudis (sg) weaned steer calves grazing in a temperate environment. within breeds, one half of the calves was untreated: aau (n = 17) and sgu (n = 18) while the other half was treated with moxidectin monthly: aat (n = 14) and sgt (n = 14). all calves were grazed on the same contaminated pasture from autumn to winter, when each group was separated to ...19957571331
the prevalence and epidemiology of gastrointestinal parasites of horses in victoria, australia.a quantitative post mortem study of 150 horses from victoria was conducted to determine the prevalence and epidemiology of gastrointestinal parasites. a total of 42 species of metazoan parasite was found. the following species of non-cyathostome parasite were found (% prevalence): trichostrongylus axei (51%); habronema muscae (13%); h. majus (2%); draschia megastoma (5%); gastreophilus intestinalis (81%); g. nasalis (29%); parascaris equorum (5%); anoplocephala perfoliata (29%); fasciola hepatic ...19957657457
seasonal changes and inhibited development of the abomasal nematodes of sheep and goats in saudi arabia.from august 1991 to july 1992, a total of 48 abomasa from sheep and 48 from goats were examined at the jeddah abattoir for the presence of adult and larval nematodes. twenty-three of the sheep (47.9%) and 21 of the goats (43.8%) were infected with nematodes, a total of eight species being found. haemonchus contortus and marshallagia marshalli appeared to be the most important parasites. other species were less prevalent: trichostrongylus axei, camelostrongylus mentulatus, parabronema skrjabini, ...19957676605
a middle-repetitive dna sequence element in the sheep parasitic nematode, trichostrongylus colubriformis.a novel repetitive dna sequence in the sheep parasitic nematode trichostrongylus colubriformis was cloned and sequenced. a 1.1 kb repetitive sequence (tc15) which hybridized with dna from t. colubriformis but not with dna from two other parasitic nematodes, haemonchus contortus and ostertagia circumcincta, or sheep was further characterized. southern blot analysis showed that the repeat hybridized to a range of fragments in restriction digested t. colubriformis dna and existed in multiple copy n ...19947970890
the effects of anthelmintics on ovine larval nematode parasite migration in vitro.the anthelmintics ivermectin, levamisole, morantel tartrate and thiabendazole all inhibited, in vitro, the motility of third stage larvae (l3) of trichostrongylus colubriformis. the bioassay, based on the inhibition of l3 migration from agar gels, yielded sigmoid dose-response curves for ivermectin, levamisole and morantel tartrate, but not thiabendazole. the concentration of levamisole giving 50% inhibition of migration (ec50) was determined for cooperia curticei, haemonchus contortus, nematodi ...19948070948
transmission of some species of internal parasites in horses born in 1990, 1991, and 1992 in the same pasture on a farm in central kentucky.studies were conducted on transmission of natural infections of several species of internal parasites in horses born and kept on the same pasture on a farm in central kentucky. data for the first year (1989) of a 4 year study on this farm have been published recently. the present research represents the second (1990), third (1991), and fourth (1992) years of the investigation. the number of animals (n = 28) examined varied from eight born in 1990 to ten each born in 1991 and 1992. for each year, ...19948073609
seasonal prevalence of gastrointestinal nematodes in communal land goats from the highveld of zimbabwe.on six occasions during a 1 year period, goats run on communal pastures by small-scale farmers, were purchased, housed indoors for 3 weeks and autopsied for examination of their gastrointestinal nematode burden. all of the 32 goats examined were infected. the four dominant species, haemonchus contortus, trichostrongylus axei, trichostrongylus colubriformis and oesophagostomum columbianum, were present in 88-97% of the animals. three other nematodes, strongyloides papillosus, bunostomum spp. and ...19948171826
efficacy of injectable abamectin against gastrointestinal tract nematodes and lungworms of cattle.efficacy of abamectin against gastrointestinal tract nematodes and lungworms of cattle was determined in 4 experiments. the first 2 experiments were controlled trials in which efficacy was determined at necropsy in calves with either experimentally induced (n = 14) or naturally acquired (n = 16) infections. half the calves in each experiment were treated with abamectin (200 micrograms/kg of body weight, sc), and half were left untreated as controls. efficacy was > 99% against adult stages of dic ...19948192257
[helminth parasites of capybaras (hydrochaeris hydrochaeris) on sub-region of nhecolândia, pantanal, mato grosso do sul].a sequence of 23 necropsies was carried out on capybaras (hydrochaeris hydrochaeris) from the central area of nhecolândia, pantanal region, state of mato grosso do sul, brazil, from december 1984 to december 1986. the helminths identified and their respective prevalences and mean intensity were: trichostrongylus axei--60.9 and 14, viannella hydrochoeri--95.6 and 1031, strongyloides chapini--47.8 and 1014, yatesia hydrochoerus--44.4 and 6, cruorifilaria tuberocauda--40.0 and 8, capillaria hydroch ...19948209035
activity of doramectin against nematode endoparasites of cattle.a series of 28 controlled anthelmintic studies, involving 634 cattle, was conducted throughout north america and europe to evaluate the efficacy of doramectin against a broad range of gastrointestinal parasitic nematode species and lungworms in naturally and experimentally infected animals. within each study, one or two groups were treated with doramectin at 200 micrograms kg-1 and another group received no drug treatment. worm burdens were estimated by standardised techniques, and efficacy asse ...19938236735
efficacy of doramectin against field nematode infections of cattle in latin america.two studies were conducted, one in argentina and one in brazil, to evaluate the therapeutic efficacy of doramectin administered subcutaneously at a dose rate of 200 micrograms kg-1 (1 ml per 50 kg) to cattle harboring mixed field infections of gastrointestinal nematodes. in each trial, 20 heifers were randomly allocated to a control or treated group of ten animals each, on the basis of fecal egg counts. animals in the treated and control groups received an injection of doramectin or saline in th ...19938236736
stomach parasites of donkeys in morocco: habitat and interspecific hundred and four donkeys originating from several regions of morocco were necropsied during 1 year. the parasites in their stomachs were counted and locations determined in the cardiac, fundic and pyloric portions. synergistic or antagonistic interactions between parasites were assessed by a principal component analysis. gasterophilus intestinalis was only found in the cardiac portion and g. nasalis was mostly found in the pyloric portion. habronema were principally encountered in the pylori ...19938249256
efficacy of abamectin against nematodes in cattle.eight controlled trials were conducted, using 96 cattle of european breeds, to evaluate the efficacy of abamectin against natural and artificially acquired infections of adult and fourth-stage larvae of all the economically important gastrointestinal nematodes and lungworms in germany and the united kingdom. half the animals were treated on one occasion with abamectin at a dose of 200 micrograms/kg bodyweight given subcutaneously while the other half remained untreated. worms were counted 14 or ...19938442334
parasitic gastritis in a llama (lama glama) associated with inhibited larval teladorsagia spp. (nematoda: trichostrongyloidea).a 7-year-old female llama was experimentally infected with 500 fasciola hepatica metacercariae then turned out onto pasture also grazed by domestic sheep. the llama was necropsied approximately 22 weeks post infection. routine examination of the gastrointestinal tract revealed diffusely coalescing, umbilicated nodules covering the caudal one-fifth of the third stomach compartment. microscopically, the mucosa was irregularly thickened. numerous nematode larvae were present in glandular lumens, of ...19938447076
epidemiology of ostertagia ostertagi in weaner-yearling cattle.epidemiologic events in the life cycle of ostertagia ostertagi are best known in the weaner-yearling phase of cattle development throughout the concentrated cattle-rising areas of the world. animal and pasture management demands placed on this age class are greater than for suckling calves and adult stock in either beef or dairy breeds. this fact alone would likely account for a higher prevalence of clinical and subclinical disease in weaner-yearlings. additionally, the developing immune respons ...19938484223
a key to the identification of arrested gastrointestinal nematode larvae of sheep in britain.a simple key is presented for the identification of arrested larval nematodes recovered from the gastrointestinal tract of sheep slaughtered in britain. the parasites included in this key are those species which are most commonly seen to undergo arrested development in sheep. they include teladorsagia (ostertagia) spp., haemonchus contortus, trichostrongylus axei, intestinal trichostrongylus spp., nematodirus battus, nematodirus filicollis, and cooperia spp. easily identifiable morphological fea ...19938493769
pattern of abomasal helminths in fallow deer farming in umbria (central italy).five helminth species were seen in the abomasa of 29 farmed fallow deer. spiculopteragia asymmetrica was most common in both prevalence (96.6%) and abundance (166.2). ostertagia drozdzi, ostertagia arctica and spiculopteragia quadrispiculata were also recovered with high prevalence (79.3-93.1%); trichostrongylus axei was sporadic (3.4%). yearlings had worm counts of 496-1480, adult males of 168-1720 and females of 18-2008. for nine of 13 deer, the faecal egg counts were negative and post-mortem ...19938493770
the reappearance of eggs in faeces of horses after treatment with ivermectin.the reappearance of nematode eggs in faeces after ivermectin treatment was studied in 104 horses on 10 farms during the stabling period. faecal samples were taken at weekly intervals. sampling was discontinued when the mean egg output per farm was > 10% of the pre-treatment egg output. this point was reached after 63 days, when the mean output of eggs had decreased to 70.3%. before treatment, 95.9% of the cultured larvae were of the cyathostome type, the others belonged to gyalocephalus capitatu ...19938498011
immunodiagnosis of taenia saginata in cattle using hydrophobic antigens from t. hydatigena metacestode cyst fluid.hydrophobic fractions isolated from cyst fluid of taenia hydatigena metacestodes, obtained from naturally infected goats from tanzania, were used in an indirect elisa and in immunoblot (western or dot blot) procedures. the use of the most hydrophobic fractions of the cyst fluid proved to result in a better diagnostic discrimination in elisa than the more hydrophilic fractions. best diagnostic ratio between responses from t. saginata infected and non-infected cattle was achieved when using horse- ...19958541896
persistence of the effect of a moxidectin pour-on against naturally acquired cattle a controlled trial with 32 calves on the persistence of the effect of a 0.5 mg/kg moxidectin pour-on against cattle nematodes the following periods of persistence were observed: virtually 100 per cent efficacy for more than five weeks against dictyocaulus viviparus (total numbers and juveniles) and ostertagia species (total numbers, inhibited early fourth stage larvae [l4] and juveniles); over 97 per cent for more than four weeks against trichostrongylus axei (total numbers, inhibited early t ...19958560714
genetic markers for closely-related parasitic species of closely-related nematode parasite (trichostrongylus axei, t. colubriformis, t. probolurus, t. retortaeformis, t. rugatus, t. vitrinus and t. tenuis) were characterized using a polymerase chain reaction-linked restriction fragment length polymorphism technique (pcr-rflp). the rdna region spanning the first and second internal transcribed spacers as well as the 5.8s rdna gene (its+) was amplified from isolates of each of the seven species, digested separately with six restriction ...19958569771
natural infection by gastrointestinal and bronchopulmonary nematodes in mouflons (ovis musimon) and their response to netobimin treatment.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 c ...19968627934
helminth parasites and hypobiosis of nematodes in n'dama cattle during the dry season in the gambia.three series of necropsies of cattle were performed, corresponding to early dry season, approximately 1 month after the last rains (november, n = 6), mid dry season (february, n = 6) and end dry season (april, n = 3). eggs per gram of faeces (epg) were determined just before necropsy. three trematodes (fasciola gigantica, schistosoma spp. and paramphistomatids) and 11 nematodes were identified from cattle, with the prevalence rate varying from 6.7% to 100%. haemonchus contortus was the most abun ...19958644452
[helminth burden of slaughter sheep in upper bavaria. 1: species spectrum, infestation extent and infestation intensity].the helminth fauna of 136 slaughtered sheep (99 lambs < 1 year, and 37 sheep > or = 1 year) from upper bavaria, germany, was examined. in all 2 species of trematodes, 3 species of cestodes and 24 species of nematodes were found. all the animals harboured gastrointestinal nematodes, 9 of them liver flukes, 33 moniezia spp., 19 cysticercus tenuicollis, and one sheep setaria sp. lungworms were not seen. the most prevalent species were cooperia curticei (74.3%), trichuris ovis (69.1%), ostertagia ci ...19968694743
dietary protein for young grazing sheep: interactions with gastrointestinal parasitism.effects of protein supplementation and of nematode control on production responses in young grazing sheep and on nematode population dynamics were assessed. young merino wether sheep (n = 270) were allocated to one of three supplementation (su) treatments and one of three regimes of nematode control (drench, dr) in a factorial design. each of the nine treatments was replicated three times in a randomised complete block. animals received no supplement (su0) or were given supplements at a level eq ...19958747911
immune responsiveness of nematode-resistant or susceptible romney line-bred sheep to continuous infection with trichostrongylus axei.two divergent lines of romney sheep have been selected on the basis of differences in faecal egg counts (fec) to natural poly-generic parasite challenge in new zealand. however, it is not known if the expression of resistance or susceptibility extends to parasitic nematodes that were not a major part of the selection challenge. to examine this, the immune response to infection with trichostrongylus axei was examined in these sheep lines. changes in the proportions of cd5+, cd4+, cd8+, t19+ and c ...19968797283
observations on the epidemiology of gastrointestinal nematodes of farmed red deer in central southern england.the epidemiology of the gastrointestinal nematodes of farmed red deer was followed over three years on two farms in north hertfordshire. worm counts on 10 animals (four months to 10 years old) between november and march showed that mixed ostertagid infections were dominant with very small numbers of trichostrongylus axei, cooperia punctata and oesophagostomum species also present in some individuals. an increase in the faecal nematode egg count of the hinds in summer was followed by an increase ...19968883346
efficacy of moxidectin pour-on against gastrointestinal nematodes and dictyocaulus viviparus in cattle.twenty crossbred beef heifer calves were used for an efficacy evaluation of 0.5% moxidectin pour-on against gastrointestinal nematodes and dictyocaulus viviparus. the latter parasite and bunostomum phlebotomum were the target species. the calves were exposed to natural infection on pasture from late september to december 22. additionally, all calves were experimentally infected with b. phlebotomum at 71 and 29 days before treatment and with d. viviparus at 29 days before treatment. the 20 calves ...19968893482
prevalence and epidemiology of trichostrongylids in wyoming cattle with consideration of the inhibited development of ostertagia ostertagi.during 1988, monthly collections of abomasa and the cranial portion of the small intestine of 208 native wyoming cattle were examined for adult and larval helminth parasites. egg counts were performed on colonic faecal specimens. the animals ranged from 7 months to 8 years of age and were sampled at slaughter houses or diagnostic laboratories from five different counties in the state. most of the cattle had ranged for a long time on non-irrigated, high altitude grass plains from about 1250 to 25 ...19968893483
sequential cellular and humoral responses in the abomasal mucosa and blood of romney sheep dosed with trichostrongylus axei.abomasal cannulae were surgically placed in 7 2-year-old new zealand romney sheep which had been maintained parasite-free from birth. four of these sheep were randomly selected and dosed orally with 10,000 infective trichostrongylus axei larvae per week for 8 weeks, while the remaining 3 sheep served as uninfected controls. abomasal biopsy, blood and faecal samples were obtained from all sheep at regular intervals from 5 days before and until 58 days after the first infection. the sheep were the ...19968894768
efficacy of moxidectin 0.5% pour-on against naturally acquired nematode infections in cattle.the efficacy of 0.5% moxidectin pour-on at two dosages was evaluated in 30 cattle with naturally acquired gastrointestinal nematode infections. the cattle were ranked according to pretreatment fecal egg counts and body weights, and were randomly assigned from replicates to three treatment groups. the mean number of trichostrongyle eggs in pretreatment fecal samples did not differ among the groups. groups i and ii received 0.5% moxidectin pour-on at dosages of 0.25 mg moxidectin per kg body weigh ...19968916402
digital image analysis and identification of eggs from bovine parasitic microscopy and multivariate statistics were used to establish and evaluate a procedure for identification of bovine strongylid eggs. ostertagia ostertagi, cooperia oncophora, haemonchus placei, trichostrongylus axei, and oesophagostomum radiatum eggs were obtained from faeces voided by monospecifically infected calves. images of single eggs (400 x magnification) were recorded by a ccd camera fitted onto a microscope and digitized on a pc. after separation of eggs from the image ...19968960211
comparison of moxidectin oral gel and ivermectin oral paste against a spectrum of internal parasites of ponies with special attention to encysted cyathostome larvae.two dosages of moxidectin oral gel were evaluated and compared to a therapeutic dose of ivermectin oral paste in the control of a spectrum of gastrointestinal parasites of ponies naturally infected in southern louisiana or mississippi. thirty-two mixed-breed ponies ranging in age from one to 21 years were used in this controlled test. eight weeks prior to the experiment, ponies grazing on contaminated pasture were moved to a paddock and fed a pelleted ration, thus reducing or eliminating the pot ...19968966989
seasonal pattern of inhibition of ostertagia ostertagi in calves in northeast mississippi.the composition of, and seasonal changes in, populations of gastrointestinal parasites of calves in northeast mississippi were determined for 10 months post-weaning. after weaning on 15 october, 20 mixed breed beef steers were grazed together on a 4 ha fescue/bermudagrass pasture. from november through august of the following year, two of the calves were removed each month for necropsy and counting of gastrointestinal nematodes. eight species of worms were found: haemonchus placei, ostertagia os ...19968983154
[endoparasites of donkeys and horses kept in communal housing in upper bavaria; species spectrum and incidence].in this epidemiological study of endoparasites 37 donkeys and 23 horses were included, which were examined coproscopically in regular intervals over a 15 month period. the animals derived from ten farms, in which regular prophylactic treatments with anthelmintics had been practiced at least for two years before this investigation. this study revealed the presence of at least twelve parasite species in donkeys, eimeria leuckarti, gasterophilus intestinalis, fasciola hepatica, anoplocephala perfol ...19968999593
the epidemiology of gastrointestinal nematode infections in communal cattle and commercial beef cattle on the highveld of epidemiological study of gastrointestinal nematode infections of cattle was conducted on the highveld of zimbabwe from june 1993 to may 1995. the study was carried out in two communal areas, two conventional beef farms and two commercial beef farms with irrigated pastures. on all farms/areas, faecal egg counts were low (< 500 eggs per g faeces) during the dry season. during the rainy season faecal egg counts were highest in communal areas and lowest in conventional beef farms. those of irriga ...19969011020
monthly fluctuations of worm burdens and hypobiosis of gastrointestinal nematodes of calves in extensive management systems in the pyrenees (spain).monthly fluctuations of worm burdens and arrested development of gastrointestinal nematodes in cattle from a mountainous region of spain were studied. fourteen previously helminth-naive calves grazed together with a herd of 120 cattle from may to november following the traditional extensive grazing system used in mountainous regions of spain (permanent calves). each month, throughout the grazing season, two helminth-naive calves (tracer calves) were added to the herd and allowed to graze for 4 w ...19969017870
eprinomectin: a novel avermectin for use as a topical endectocide for cattle.eprinomectin (mk-397 or 4"-epi-acetylamino-4"-deoxy-avermectin b1) is a novel avermectin selected for development as a topical endectocide for all cattle, including lactating dairy cows. herein, we show its anthelmintic, insecticidal and miticidal activity. to determine its anthelmintic capabilities, eprinomectin was tested topically on jersey calves at 0.08, 0.2, or 0.5 mg kg-1 in a probe formulation against experimental infections of adult haemonchus placei, ostertagia ostertagi, trichostrongy ...19969024867
persistent efficacy of abamectin and doramectin against gastrointestinal nematodes of assess the persistent activity of injectable formulations of abamectin and doramectin against gastrointestinal nematodes of cattle.19979034496
efficacy of doramectin for treatment of experimentally induced infection with gastrointestinal nematodes in determine the efficacy of injectable doramectin against experimentally induced infections with adult and larval (l4) stages of gastrointestinal nematodes in calves.19979055975
hypobiosis in the ostertagids of red deer and the efficacy of ivermectin and fenbendazole against abattoir survey was carried out during the 1991 to 1992 slaughter season to examine the structure of the ostertagid populations in red deer. most of the animals were 15- to 22-month-old stags, but there were also hinds on two occasions and calves on one. ostertagids of mixed species were present in all of the animals, and 43 of 120 (35.8 per cent) stags and 10 of 17 (58.8 per cent) hinds, but no calves, also carried small numbers of trichostrongylus axei. most animals carried adult and develo ...19979061873
evaluation of the persistence of the effect of ivermectin and abamectin against gastrointestinal and pulmonary nematodes in cattle.the persistence of the effect of ivermectin and abamectin against gastrointestinal nematodes and lungworm in cattle was evaluated in two trials, each involving 28 animals. groups of seven cattle either remained untreated, or were treated topically with ivermectin at 500 micrograms/kg bodyweight or subcutaneously with either ivermectin or abamectin at 200 micrograms/kg bodyweight. starting on the day of treatment the cattle were given daily trickle infections with various infective nematode larva ...19979090034
efficacy of a pour-on formulation of eprinomectin (mk-397) against nematode parasites of cattle, with emphasis on inhibited early fourth-stage larvae of ostertagia evaluate efficacy of topically applied eprinomectin against inhibited early fourth-stage larvae (il4) of ostertagia spp in calves.19979099383
nematocidal efficacy of eprinomectin, delivered topically, in naturally infected assess the nematocidal efficacy of eprinomectin in naturally infected cattle.19979185967
epidemiological observations on gastrointestinal nematode infections in grazing cow-calf pairs in belgium.the epidemiology of gastrointestinal helminth infections in beef cows and calves on pasture was studied in belgium during the 1990 and 1992 grazing seasons. weight gain, faecal egg counts, generic differentiation of infective larvae, serum pepsinogen levels, herbage larval counts and worm burdens of tracer calves were used as parameters. in study 1 two groups of ten cows with their spring-born calves grazing on separate pastures (a and b) were monitored during the 1990 grazing season. ostertagia ...19979187031
effect of simulated rain, coat length and exposure to natural climatic conditions on the efficacy of a topical formulation of eprinomectin against endoparasites of cattle.a series of five controlled studies involving 114 cattle were conducted in australia, north america and the united kingdom to examine the effect of simulated rain, coat length and exposure to natural climatic conditions, on the efficacy of a topical formulation of eprinomectin against nematode parasites of cattle. in all trials infections were induced with a range of bovine nematode species and treatment was applied when the majority of nematodes were mature. in one study, simulated rain was app ...19979187034
controlled dose confirmation study of a 2% moxidectin equine gel against equine internal parasites in the netherlands.the efficacy of a 2% moxidectin equine gel at a dosage rate of 0.4 mg kg-1 was evaluated in a controlled trial at utrecht university. twelve yearling castrated male shetland ponies grazed a pasture of 2 ha from may 1994 until housing in november. six ponies were treated with moxidectin, whereas the others served as non-treated controls. necropsy was carried out 35 days after treatment. greater than 99% efficacy of moxidectin was observed on faecal egg output. no effect of moxidectin was observed ...19979195720
abomasal nematodes in goats from the subtropical island of grand canary (spain).the prevalence of gastric nematodes in 151 goats on grand canary island is around 56%, with a mean burden of 691 worms/animal. no significant differences of prevalence and intensity were found between the four isoclimatic areas of the island [dry-desert (dd); dry-steppe (ds); temperate-mild (tm); temperate-cold (tc)]. five nematode species were identified, the most commonly-occurring being teladorsagia circumcincta (observed in 65.8% of parasitized animals) and trichostrongylus axei (51.9%). the ...19979208446
occurrence of gasterophilus intestinalis and some parasitic nematodes of horses in sweden.a survey was performed on the occurrence of some internal parasites in 461 horses (1-30 years old) slaughtered from october 1992 to september 1993 at the linköping abattoir in central sweden. macroscopical examination was carried out specifically for parasites of the tear ducts and conjunctival sacs of the eyes, and of selected parts of the alimentary tract and cardio-vascular system. the following parasites were found in selected parts of the large intestine: encapsulated cyathostome larvae (in ...19979257451
quantification of total sheep ige concentration using anti-ovine ige monoclonal antibodies in an enzyme immunoassay.monoclonal antibodies (mabs) which recognize separate epitopes on ovine immunoglobulin e (ige) have been used to develop a non-competitive antibody sandwich enzyme immunoassay (eia) for quantitating ovine ige. purified anti-ige mab (yd3) coated onto polystyrene microtitre plates was used to capture ige in serum samples. biotinylated anti-ige mab (xb6) followed by streptavidin conjugated with horseradish peroxidase were used to detect captured ige. tetramethylbenzidine and h2o2 were used as enzym ...19979261963
therapeutic and prophylactic efficacy of the ivomec sr bolus against nematodes and psoroptes ovis in cattle weighing more than 300 kg at the time of treatment.three trials using 50 european breed cattle were conducted to evaluate the therapeutic and prophylactic efficacy of the ivomec sr bolus against nematodes (2 trials) and psoroptes ovis (1 trial) in cattle weighing more than 300 kg at the time of treatment. the ivomec sr bolus proved to be highly effective against economically important gastrointestinal and pulmonary nematodes (ostertagia ostertagi, trichostrongylus axei, cooperia punctata, oesophagostomum radiatum, dictyocaulus viviparus) and imp ...19979272566
some aspects of inhibited development of trichostrongylids in ruminants.inhibited development is an important aspect of the biology of some gastrointestinal nematodes of ruminants, particularly species of the subfamily ostertagiinae and haemonchus spp. there is a seasonality in the occurrence of the phenomenon. it tends to occur predominantly during the unfavourable season for the free-living stages. thus 'winter' and 'summer-dry season' patterns of inhibition can be observed. furthermore, the phenomenon is influenced by immunity of the host and by management factor ...19979460202
host specificity of sheep and cattle nematodes in são paulo state, brazil.the trial was carried out to investigate parasite host specificity and to analyse the dynamics of infection with nematodes parasitizing sheep and cattle raised together or separately in são paulo state, brazil, and, also to clarify doubts about the systematics of species of the genus haemonchus on the basis of cytological and morphological studies. ten steers and 32 ewes were randomly assigned to three paddocks (p), as follows: p1, 5 steers; p2, 5 steers and 16 ewes; and p3, 16 ewes. the animals ...19979477496
the efficacy of eprinomectin against induced infections of immature (fourth larval stage) and adult nematode parasites in cattle.eprinomectin is a new endectocide of the avermectin chemical group developed for use in cattle. to establish its effectiveness against cooperia spp., dictyocaulus viviparus, haemonchus contortus, nematodirus helvetianus, oesophagostomum radiatum, ostertagia ostertagi, trichostrongylus axei and trichostrongylus colubriformis (immature infections only), six trials were conducted in europe at two trial sites. in each trial, animals were artificially infected with a number of nematode species and tr ...19979477498
parasites of stomach and small intestine of 70 horses slaughtered in the netherlands.the prevalence of metazoan parasites in the stomach and small intestine was investigated in 70 horses slaughtered in the period february 1994-july 1994. most horses were young (1.5-3 years) and in good condition. trichostrongylus axei was the most prevalent parasite species in the stomach (51.4%), followed by gasterophilus intestinalis (41.4%) and habronema spp. (4.3%). in the small intestine, parascaris equorum (28.6%) and paranoplocephala mamillana (1.4%) were found. the mean worm burden of t. ...19989477534
epidemiology of mecistocirrus digitatus and other gastrointestinal nematode infections in cattle in mindanao, philippines.over a period of 14 months, faecal and serum samples were collected monthly from cattle of 1 to 30 months old on three ranches (20-25 animals ranch-1 sample-1) in mindanao, philippines. individual faecal egg counts, serum pepsinogen levels and mecistocirrus digitatus specific antibodies were determined, and infective larvae from pooled faecal samples were examined. post mortem worm counts were carried out on tracer calves (n = 16) that had been kept for 30 days with the herds on two of the ranch ...19989493308
efficacy of moxidectin 2% equine gel against natural nematode infections in ponies.the efficacy of moxidectin 2% oral gel (equest, fort-dodge) against european worm strains was studied through post-mortem worm counts and feacal egg counts (fecs) in 12 young ponies naturally infected. the animals were allocated in two groups of six ponies each: the first one was treated at 0.4 mg/kg b.w. and the second one received a placebo and served as control. all the ponies were necropsied 14 days post-treatment. the efficacy of moxidectin in reducing strongyle fecs ranged from 99.8% to 10 ...19989493313
efficacy of an ivermectin controlled-release capsule against nematode and arthropod endoparasites in sheep.five controlled trials were conducted in germany or in the united kingdom, using 74 female sheep of merino or dorset horn breeds, to evaluate the efficacy of an ivermectin controlled-release capsule against naturally acquired or induced infections of gastrointestinal nematodes, lungworms and nasal bot larvae and against incoming infections with gastrointestinal and pulmonary nematodes. half of the animals were treated with one ivermectin controlled-release capsule that delivered ivermectin at th ...19989571756
comparative analysis of two methods used to show interspecific associations in naturally acquired parasite nematode communities from the abomasum of ewes.the aim of our study was to compare a multivariate and a univariate method to evaluate the associations between nematode species in natural infections. we used a data set based on the 3-year study of the community of abomasal nematodes in ewes of the middle-atlas region of morocco. frequency data (percentage of each species in the individual host community) were processed by principal component analysis. euclidean distances between species (d2) were calculated from projections of principal compo ...19989650865
a comparison of the first internal transcribed spacer of ribosomal dna in seven species of trichostrongylus (nematoda: trichostrongylidae).the first internal transcribed spacer (its-1) of the ribosomal dna of seven species of trichostrongylus was sequenced. the length of its-1 in the different species varied from 387 to 390 bases. the g + c content of the its-1 sequences were approximately 42%. little or no intraspecific variation was detected in the three species. trichostrongylus axei, trichostrongylus colubriformis and trichostrongylus vitrinus, for which multiple isolates from different geographical regions were sequenced. in c ...19989762572
comparative efficacy evaluation of moxidectin gel and ivermectin paste against internal parasites of equines in brazil.a total of 24 male and female equines of mixed breed, 10-20 months of age and naturally infected with internal parasites was utilized in a controlled test to evaluate the efficacy of a moxidectin 2% gel formulation at the dosage of 0.4 mg moxidectin per kg of live weight and an ivermectin 1.87% commercial paste formulation at the dosage 0.2 mg ivermectin per kg applied orally. animals were allocated into three groups of eight horses each based on pre-treatment eggs per gram (epg) counts and trea ...19989877068
[helminth species of goats in germany].the helminth fauna of the gastrointestinal tract of 25 and the respiratory organs and the livers of 6 german goats was qualitatively and quantitatively examined. one trematode species (dicrocoelium dendriticum), 2 species of cestodes (moniezia expansa and metacestodes of taenia hydatigena) and 28 species of nematodes (24 in the gastrointestinal tract and 4 in the lungs) were recorded. two goats were infested with oestrus ovis larvae. the most prevalent species were ostertagia circumcincta and ch ...19989880938
efficacy of topically administered doramectin against eyeworms, lungworms, and gastrointestinal nematodes of evaluate efficacy of topically administered doramectin against eyeworms, lungworms, and gastrointestinal nematodes of cattle.199910376888
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 dif ...199910386433
predatory behaviour of trapping fungi against srf mutants of caenorhabditis elegans and different plant and animal parasitic nematodes.the initial infection process of nematode-trapping fungi is based on an interaction between the trapping structure of the fungus and the surface of the nematode cuticle. a bioassay was designed to investigate the predatory response of several isolates of nematode-trapping fungi against 3 mutants of caenorhabditis elegans (at6, at10 and cl261), which have been reported to differ in the reaction of their cuticle to antibodies and lectins. the bioassay was also applied to infective larvae of animal ...199910446708
parasite diversity and anthelmintic resistance in two herds of horses.diversity of parasite populations was compared between two herds of horses, one a regularly treated herd the other a feral herd which has bad no anthelmintic treatment for at least 25 years. eggs obtained from fecal samples of both herds were tested for anthelmintic resistance by use of an in-vitro larval hatch/development assay (lda), drenchrite. a fecal egg reduction test was also performed with the domesticated herd using fenbendazole, pyrantel pamoate and ivermectin. cyathostomes were the pr ...199910485366
gastro-intestinal parasites of cattle in the communal grazing system of botshabelo in the free state.twelve bonsmara tracer calves (aged 6-12 months) were used to monitor helminth infections in the communal farming system of botshabelo in the free state. one calve was slaughtered each month from december 1995 to november 1996 and processed for helminth recovery. all the calves harboured worms, but the numbers were always low. the order of prevalence of the major parasites was trichostrongylus axei, haemonchus placei, cooperia punctata and cooperia pectinata.199910486833
dose confirmation of moxidectin pour-on against natural nematode infections in lactating dairy cows.the nematocidal effectiveness of moxidectin, administered topically at the rate of 500 mcg/kg bw, was determined for lactating dairy cows. naturally infected animals were given either topical vehicle or moxidectin (cydectin pour-on fort dodge animal health) at the rate of 1 ml/10 kg bw (10 animals per treatment group), and sacrificed 14-18 days post-treatment for nematode enumeration. 100% efficacies were recorded for ostertagia lyrata males, cooperia punctata males and oesophagostomum radiatum ...199910536978
a comparison of the infectivity of cryopreserved versus unfrozen infective larvae of haemonchus contortus, trichostrongylus colubriformis and trichostrongylus axei. results of the onderstepoort veterinary institute and collaborators from 1977 to the present.the infectivity for sheep of cryopreserved infective larvae (l3) of various strains of haemonchus contortus, trichostrongylus colubriformis and trichostrongylus axei is compared using previously published results of trials conducted at the onderstepoort veterinary institute laboratories, and of collaborators. the means and ranges of development were similar for both frozen and unfrozen larvae of two of the three worm species reviewed. a mean of 33.4% (range, 12.7-63.0%) of cryopreserved h. conto ...199910689701
the helminths of ranch calves in the north-eastern mountain grassland of south africa.the cumulative total helminth parasite burdens of ranch calves during their first seven months of life on the north-eastern mountain grassland of south africa were determined during two consecutive years. trichostrongylus axei was the most abundant nematode parasite followed by cooperia spp. and ostertagia ostertagi. haemonchus spp. occurred in relatively low numbers and its development was significantly inhibited. the total helminth parasite burdens of the calves ranged from 681 to 7,269 with a ...199910689707
parenterally administered gastrointestinal nematode infective larvae viable after more than 15 years in liquid nitrogen.after cryopreservation for 13.3-15.8 years, the viability of the infective larvae (l3) of trichostrongylus axei, t. colubriformis, oesophagostomum columbianum, haemonchus contortus, ostertagia circumcincta, t. falculatus, nematodirus spathiger, chabertia ovina and dictyocaulus filaria was assessed in sheep, by being deposited at their predilection sites. d. filaria was, however, an exception, in that the l3 were injected into the jugular vein. the mean development of all the species was 22.8%, b ...200010714461
nematode parasites of adult dairy cattle in the netherlands.abomasa, blood samples and faecal samples for examination of nematode infections were collected from 125 dairy cows during the period november 1997-october 1998. of these, 12 had no grazing history and were, therefore, excluded from this study. from the remaining 113, 88.5% had nematode eggs in the faeces. larval identification of the positive cultures showed that ostertagia spp. larvae were most frequent (97%), followed by trichostrongylus spp. (29%), oesophagostomum spp. (23%), cooperia puncta ...200010799842
host specificity of abomasal nematodes in free ranging alpine ruminants.abomasums from 641 alpine wild ruminants representing five different species (cervus elaphus, capreolus capreolus, rupicapra rupicapra, capra ibex, ovis musimon) and from 19 domestic sheep (ovis aries) from alpine areas were examined in order to investigate the host-specificity of abomasal helminths. nine out of 20 helminth species were found in at least five different host species. a discriminant analysis was able to significantly discriminate the hosts on the basis of their helminth community ...200010842002
examination of gastrointestinal helminth in livestock grazing in grassland of 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, mecistoci ...200011002657
the epidemiology of nematode and fluke infections in cattle in the red river delta in vietnam.over a period of 13 months, faecal samples were collected monthly from approximately 45 cattle over 3 months of age. additionally, 74 calves of 1-2 months were sampled to determine the presence of toxocara vitulorum eggs. individual egg counts and infective strongyle larvae from pooled faecal samples were examined. post-mortem worm counts were carried out on six groups of tracer calves (n=12) that had been kept for 4 weeks on pasture in and around the village studied. the following helminths wer ...200011035232
persistent efficacy of topical eprinomectin against nematode parasites in cattle.six studies were conducted to evaluate the persistent efficacy of eprinomectin pour-on against experimental challenges with infective nematode larvae in calves. in each study, calves were randomly assigned to one untreated group and up to four test groups, which were treated with eprinomectin at 500 microg/kg body weight at weekly intervals before single bolus challenge. the calves were necropsied approximately 4 weeks after challenge infection for nematode recovery. eprinomectin pour-on provide ...200011097305
a study to evaluate the field efficacy of ivermectin, fenbendazole and pyrantel pamoate, with preliminary observations on the efficacy of doramectin, as anthelmintics in horses.the efficacy of ivermectin, fenbendazole, pyrantel pamoate and doramectin was evaluated under field conditions at 2 sites in the free state province of south africa. the study involved 25 horses at each site, divided into 5 groups of equal size. ivermectin, fenbendazole and pyrantel pamoate were administered orally at doses of 0.2, 10 and 19 mg/kg respectively. doramectin was administered by intramuscular injection at a dose of 0.2 mg/kg. treatment efficacy was based on the mean faecal egg count ...200011205161
cross-protection studies with gut membrane glycoprotein antigens from haemonchus contortus and teladorsagia circumcincta.gel profiles of the peanut and cona lectin binding integral membrane glycoproteins of teladorsagia circumcincta and haemonchus contortus were compared and found to be considerably different. however, some of the teladorsagia polypeptides were recognized by antisera specific for haemonchus amino-, metallo- or aspartyl peptidases, enzymes which are known to be protective antigens for that parasite. as expected, an experimental vaccine containing these haemonchus proteases was extremely effective a ...200111298297
the epidemiology of gastrointestinal nematodes of dairy cattle in central kenya.the epidemiology of h. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in kiambu district, central kenya during each of 13 one-month periods from april 1993 to april 1994. on each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. twelve of the animals were designated for bimonthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood an ...200111360797
a multiplex pcr assay for differentiating economically important gastrointestinal nematodes of cattle.a multiplex polymerase chain reaction (pcr) test was developed for identifying gastrointestinal (gi) nematodes that commonly infect cattle. this assay was developed using adult-derived genomic dna and shown capable of discriminating parasite eggs from the feces of experimentally-infected animals at both the species and genus levels. sequence data from internal (its) and external (ets) transcribed spacers of the ribosomal dna (rdna) repeats as well as the 3'-end of the small subunit rdna and 5'-e ...200111390072
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 ha ...200111780839
helminth intensity and diversity in organic meat sheep farms in centre of france.a helminthological study was undertaken at five sheep meat organic farms in the centre of france. the data obtained were compared with two extensive (contemporary of present study) or semi-intensive (literature data) conventional sheep meat farms. the nematode fauna of the region could be characterised by the presence of trichostrongylus axei alongside with the dominant species recorded in other areas (teladorsagia circumcincta and trichostrongylus colubriformis with few haemonchus contortus). t ...200211879965
the dynamics, prevalence and impact of nematode infections in organically raised sheep in sweden.a three-year survey (1997-99) was carried out on organically reared sheep flocks throughout sweden. the aim was to determine the prevalence and intensity of nematode infections and to establish relationships between sheep management practices and parasite infections. faecal samples from ewes and lambs were collected from 152 organic flocks around lambing-time and during the grazing-period for analysis. results were compared with the different management practices that farmers use to prevent para ...200111887398
kinetics of exsheathment of infective ovine and bovine strongylid larvae in vivo and in vitro.the aim of the study was to investigate the longitudinal changes of exsheathment of ovine and bovine 3rd-stage strongylid larvae in an artificial rumen (rusitec) and to compare the results with in vivo data obtained from rumen-fistulated sheep. infective larvae were incubated in nylon mesh bags in the sheep rumen or the rusitec apparatus for periods of 1, 6 and 12 h, respectively. the 12 h exsheathment rates in the rumen and the rusitec apparatus (in parentheses) were as follows: haemonchus cont ...200212166522
diagnosis of gastrointestinal nematodes infecting sheep in qalubia governorate by infective thrid stage larvae.a total of 300 faecal samples obtained from living sheep in qalubia governorate, 128 (42.66%) harboured eggs of nematodes. the gastrointestinal nematodes had been differentiated through the infective third stage larvae. details of the general and differential categories of each were given. the recovered species were trichostrongylus axei, t. colubriformis, ostertagia circumcincta, haemonchus contortus, bunostomum trigonocephalum and oesophagostomum venulosum.199912561888
[helminth infection in cattle from schleswig-holstein (germany) after one grazing season].fifteen holstein-friesian bulls which grazed together for one season (april to november) in schleswig-holstein were necropsied after housing for 2 to 6 weeks. the approximately 12-month old bulls weighed 378 to 491 kg at slaughter and did not receive any anthelmintic on pasture. the most prevalent species of the gastrointestinal tract was ostertagia ostertagi (prevalence; geometric mean worm count; minimum-maximum) (100%; 1,355; 130-4,590) followed by cooperia (c.) oncophora (86.7%; 343; 20-14,8 ...200312592928
the toxic effect of phenothiazine on cattle of the gulf coastal plain area of texas, and its efficacy in removing ostertagia ostertagi and trichostrongylus axei. 195313031001
studies on trichostrongylosis. i. the pathogenesis of trichostrongylus axei in sheep maintained on a low plane of nutrition. 195413163245
studies on trichostrongylus axei. ii. the pathogenesis of t. axei in sheep maintained on a high plane of nutrition. 195413211864
the course of infection and pathogenic effect of trichostrongylus axei in calves. 195513238744
studies on trichostrongylus axei. iv. factors in the causation of pathogenic effects by t. axei. 195513263451
studies on trichostrongylus axei (cobbold, 1879). ii. some quantitative aspects of experimental infections in rabbits. 195713429440
the effect of experimental infection with ostertagia ostertagi and trichostrongylus axei in calves on weight gain, feed consumption, and feed utilization. 195813583360
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