| occurrence and seasonal behavior of gastrointestinal nematodes infecting maine dairy cattle. | gastrointestinal tracts of 48 yearling maine dairy cattle were examined (8 animals every 2 months) for 1 year. adult and immature nematodes were identified and counted. species recovered were bunostomum phlebotomum, cooperia mcmasteri, cooperia oncophora, cooperia pectinata, cooperia punctata, haemonchus placei, nematodirus helvetianus, oesophagostomum radiatum, ostertagia circumcincta, ostertagia lyrata, ostertagia ostertagi, trichostongylus axei, and trichuris ovis. strongyle parasitism was ob ... | 1977 | 145192 |
| ostertagiosis in captive bison in new york state: report of nine cases. | type ii ostertagiosis was found at necropsy in 9 american bison (bison bison) from 3 farms in new york. clinical signs included severe diarrhea, emaciation, unthrifty coats, anemia, and weakness. in severely affected animals, the macroscopic abomasal changes consisted of irregular thickening and edema of the mucosa, resulting in a pebbly or morocco-leather appearance. microscopically, many gastric pits and glands were dilated, lined by hyperplastic epithelium, and contained nematode sections or ... | 1979 | 157257 |
| efficacy of albendazole for treatment of naturally acquired nematode infections in washington cattle. | albendazole, methyl 5-propylthio-1h-benzimidazol-2-yl carbamate, was given as a bolus (7.68 to 8.18 mg/kg of body weight) to cattle naturally infected with gastrointestinal nematodes and lungworms in a controlled trial. over 99% of adult ostertagia ostertagi, trichostrongylus longispicularis, cooperia oncophora, nematodirus helvetianus, and dictyocaulus viviparus were removed by the treatment. efficacy against immature o ostertagi, early fourth-stage o ostertagi, and oesophagostomum radiatum was ... | 1979 | 157705 |
| observations on the pathogenic effects of nematodirus helvetianus in dairy calves. | six holstein-friesian calves 3 to 5 months old, were used in a small-scale experiment to determine the pathogenic effects of the thread-necked strongyle nematodirus helvetianus. two calves were kept as controls and 4 were infected, 2 with single doses of 25,000, and 2 with 50,000 n helvetianus larvae. observations made during the 8 weeks of the experiment found that n helvetianus is capable of producing severe pathologic changes in the intestine of previously healthy calves. at 38 days after inf ... | 1979 | 453683 |
| observations on the resumption of development of inhibited ostertagia, cooperia and nematodirus infections in calves stabled overwinter. | two groups of three month old, parasite-free calves grazed a permanently infected pasture for 14 days, group a during the first two weeks of september and group b during early november. half of each group was killed 14 days after removal from the pasture and the remainder stabled overwinter before slaughter and parasitological examination. marked inhibition of development occurred for cooperia oncophora with a variable lower level of inhibition for ostertagia ostertagi and practically none for n ... | 1979 | 548165 |
| cryopreservation of the infective larvae of the common nematodes of ruminants. | exsheathed infective larvae (l 3) of 19 species of nematodes were tested for infectivity in either sheep or cattle after they had been frozen in 0,9% nacl solution, stored for a relatively short time in the gas phase of liquid nitrogen and subsequently thawed. in addition, 13 of these species were tested after similar storage for up to 18 months. in sheep, haemonchus contortus, ostertagia circumcincta, trichostrongylus axei, trichostrongylus colubriformis, nematodirus spathiger and oesophagostom ... | 1977 | 566412 |
| anthelmintic efficacy of oxfendazole in calves. | oxfendazole, methyl [5-(phenylsulfinyl)-1h-benzimidazol-2-yl]carbamate given to calves at dose level of 2.5 mg/kg as a paste, as a bolus, or as a drench resulted in excellent (97 to 100%) anthelmintic efficacy against mature ostertagia ostertagi, trichostrongylus axei, cooperia oncophora, c mcmasteri, c pectinata, c punctata, nematodirus helvetianus, trichostrongylus longispicularis, chabertia ovina, and oesophagostomum radiatum. against the early 4th stage larvage of o ostertagia and n helvetia ... | 1978 | 567947 |
| [distribution of nematode parasites of the digestive system in sheep (ovis aries) and goats (capra hircus) of the piedmontese and valdostano alpine arc]. | a survey, carried out on gastro-intestinal nematodes of sheep and goats of piemonte and of valle d'aosta (87 sheep and 12 goats) has shown the presence of the following species in sheep, bunostomum trigonocephalum, chabertia ovina, cooperia curticei, haemonchus contortus, marshallagia marshalli, nematodirus abnormalis, nematodirus filicollis, nematodirus helvetianus, nematodirus spathiger, oesophagostomum venulosum, ostertagia circumcincta, ostertagia lyrata, ostertagia trifurcata, skrjabinema o ... | 1977 | 572958 |
| anthelmintic activities of fenbendazole against nematodirus helvetianus in cattle: effect on egg production, embryogeny, and development of larval stages. | calves experimentally infected with nematodirus helvetianus were treated with a single dose of fenbendazole at the rate of 5 mg/kg of body weight. fenbendazole was found to have an efficacy of 97.4% against adult n helvetianus. additionally, eggs recovered 12 hours after calves were given the anthelmintic had fewer and frequently abnormal blastomeres. fewer eggs were evident at 36 hours after treatment, and none was found at 72 hours or later. on the culturing of eggs from manure passed at 12 ho ... | 1978 | 717880 |
| [the efficacy of fenbendazole against nematodirus helvetianus in cattle]. | | 1976 | 985309 |
| the significane of nematodirus helvetianus eggs which have survived on a pasture throughout the winter in the transmission of infection to calves. | a field experiment was carried out to determine the significance of nematodirus helvetianus eggs which had survived throughout the winter in the transmission of infection to calves turned on to a pasture in the early summer. the calves became infected but did not exhibit symptoms of clinical disease. it was concluded that eggs which survive the winter are unlikely to be associated with outbreaks of disease. | 1975 | 1168935 |
| anthelmintic activity of paraherquamide in calves. | paraherquamide, an oxindole alkaloid metabolite of penicillium paraherquei and penicillium charlesii, was tested against the adult stages of nine common gastrointestinal and lung nematodes of calves at single, oral dosages of 0.5, 1.0, 2.0 or 4.0 mg kg-1. at dosages 1.0-4.0 mg kg-1 there was 95% or more removal of haemonchus placei, ostertagia ostertagi, trichostrongylus axei, trichostrongylus colubriformis, cooperia oncophora, nematodirus helvetianus, oesophagostomum radiatum, and dictyocaulus ... | 1992 | 1413457 |
| efficacy of moxidectin against naturally acquired nematode infections in cattle. | the efficacy of moxidectin, a new endectocide against natural nematode infections, was evaluated. twenty-five calves were divided into two groups of eight calves each and a third group of nine calves. moxidectin was administered s.c. to two groups (i, 0.2 mg kg-1 body weight (bw); ii, 0.3 mg kg-1 bw) and the third group (iii) received the vehicle (placebo) s.c. two pre-treatment and one post-treatment faecal nematode egg count determinations were made from all calves, and they were necropsied 2 ... | 1992 | 1502785 |
| nematodirus helvetianus epidemiology. | | 1991 | 1801412 |
| parasites of south african wildlife. ix. helminths of kudu, tragelaphus strepsiceros, in the eastern cape province. | the helminths of 25 kudu, tragelaphus strepsiceros, from 3 localities in the eastern cape province were collected, counted and identified. the majority of kudu harboured no worms, and the burdens of those infected were small. a race of cooperia rotundispiculum, a dictyocaulus sp., a haemonchus sp., nematodirus helvetianus and ostertagia ostertagi were recovered. two parasites, nematodirus helvetianus and ostertagia ostertagi can be added to the list of helminth parasites of kudu in south africa. | 1991 | 1923383 |
| effects of tactical late-season treatments with ivermectin on calves naturally exposed to trichostrongyles. | this study was conducted to evaluate the effects of tactical treatments with ivermectin against trichostrongyles in first-season grazing heifer calves in the danish marshland. a group of black-pied friesian calves was turned out in early may on a permanent pasture naturally infected with trichostrongyle larvae. in late july, when high herbage infectivity started to appear, the pasture was divided into two plots of equal size, which from then and until housing in late october were each grazed by ... | 1990 | 2251746 |
| cryopreservation of some common nematodes of ruminants for up to 11,3 years. | infective larvae of selected batched of the following nematode species from sheep and cattle were examined for survival and infectivity (by injection into either the abomasum, the duodenum, or the jugular vein) after having been stored in liquid nitrogen for 103-136 months: haemonchus contortus, haemonchus placei, ostertagia circumcincta, ostertagia ostertagi, marshallagia marshalli, cooperia spp., trichostrongylus axei, trichostrongylus colubriformis, trichostrongylus falculatus, nematodirus sp ... | 1990 | 2338992 |
| [the helminth fauna of the gastrointestinal tract of young cattle in northwest germany]. | ten unmedicated animals of a controlled anthelmintic trial were used to analyse the present gastrointestinal helminth fauna of young cattle from the northwest of germany. this survey done in august revealed ostertagia ostertagi to represent the most prevalent and abundant species followed by cooperia oncophora and nematodirus helvetianus. o. lyrata, o. leptospicularis, c. zurnabada, c. punctata, trichostrongylus axei, haemonchus contortus, bunostomum phlebotomum, capillaria bovis and trichuris d ... | 1989 | 2598802 |
| comparison of egg excretion and serum pepsinogen levels as measures of nematode worm burdens in calves with limited pasture exposure. | four- to 6-mo-old calves raised on clean pastures were allowed to graze for about 30 days on pastures naturally contaminated with ostertagia ostertagi, cooperia spp., haemonchus placei, and nematodirus helvetianus. the calves were then housed on concrete for 3 wk before slaughter. at necropsy the eggs per gram of feces (epg) and the total worm burdens from the abomasum and small intestine were determined. blood samples were also obtained for serum pepsinogen (pep) assays. a total of 44 calves wa ... | 1989 | 2723922 |
| prophylactic efficacy of an ivermectin sustained-release bolus against challenge exposure with gastrointestinal and pulmonary nematode infective larvae in calves. | twelve holstein calves were used to determine the prophylactic efficacy of ivermectin against challenge exposure with gastrointestinal and pulmonary nematodes. two groups of 6 calves (mean body weight, 205 kg) each were formed by restricted randomization according to body weight. group-1 calves served as nonmedicated controls. each calf of group 2 was orally given one prototype sustained-release bolus designed to deliver ivermectin at a continuous daily dose of 8 mg. third-stage nematode infecti ... | 1988 | 3189987 |
| the prophylactic effect of ivermectin treatments on gastrointestinal helminthiasis of calves turned out early on pasture or late on mown pasture. | a study was undertaken to ascertain the prophylactic effect on gastrointestinal helminthiasis of (1) a single ivermectin treatment of calves 3 weeks after a late turnout on mown pasture and (2) two ivermectin treatments of calves 3 and 8 weeks after an early turnout. the single ivermectin treatment after a late turnout on mown pasture appeared to be an effective control measure for infections of cooperia and, in particular, ostertagia. the two treatments after an early turnout were also effectiv ... | 1988 | 3369082 |
| seasonal prevalence of gastrointestinal nematodes of beef calves grazed on irrigated pastures in the lower sacramento valley of california. | two worm-free calves were allowed to graze on irrigated pasture with a naturally infected herd for each of 34 one-month periods from november 1979 to august 1982. after each grazing period, the calves were transferred to a cement-floored pen for 3 weeks and then were euthanatized and necropsied. ostertagia ostertagi and cooperia oncophora were the most prevalent species of nematodes recovered. adults and larvae of ostertagia spp and cooperia spp were most numerous in winter and spring and least ... | 1988 | 3377319 |
| anthelmintic efficacy of netobimin against naturally acquired gastrointestinal nematodes in yearling heifers. | the efficacy of netobimin (coded sch 32481, schering corporation) in removing naturally acquired gastrointestinal nematode infections was evaluated in 10 treated and 10 untreated (control) yearling beef heifers. the anthelmintic was administered as an oral drench at a dose level of 7.5 mg kg-1 body weight. fecal egg per gram (epg) counts were reduced with netobimin by 98% (p less than or equal to 0.01) at both 1 and 2 weeks post-treatment (pt). the compound was highly effective in removing oesop ... | 1987 | 3439007 |
| efficacy of morantel sustained release bolus against gastrointestinal nematodes in first season grazing holstein calves. | the efficacy of the morantel sustained release bolus (msrb) in reducing gastrointestinal parasitism in first season grazing calves was evaluated during the summer--autumn grazing seasons of 1982 and 1983 in western oregon. each of 38 calves (1982) and 40 calves (1983) were randomly assigned to either control or treatment groups which were given msrb on the day of turnout onto pasture. mean worm burdens from tracer calves grazed with treated animals in 1982 and 1983 showed overall reductions of 8 ... | 1987 | 3564351 |
| strains of cattle parasites in the netherlands with different propensities for inhibited development. | a field study was undertaken of the possible differences in propensity for inhibited development in strains of cattle nematodes from two different locations in the netherlands. in one location (lelystad) the strains were thought to lack the ability for inhibited development as a result of environmental stimuli on the infective larvae, while in the other location (utrecht) this ability was presumed to be present. the lelystad strains were kept at the original location and were also transferred to ... | 1987 | 3590614 |
| prophylaxis of nematode infections in cattle with an indwelling rumino-reticular ivermectin sustained release bolus. | ivermectin delivered continuously from a rumino-reticular sustained release device was prophylactically effective in preventing establishment of nine nematode parasite species in multiply-exposed cattle. ivermectin dosages which permitted less than or equal to 1% of infected control calf worm populations to establish ranged from less than 2.5 micrograms kg-1 day-1, which totally prevented infection with dictyocaulus viviparus and oesophagostomum radiatum, to approximately equal to 30 micrograms ... | 1986 | 3788027 |
| the prophylactic effect of ivermectin treatment of calves, three weeks after turnout, on gastro-intestinal helminthiasis. | in two grazing experiments carried out in 1982 and 1983 the prophylactic effect on gastro-intestinal helminthiasis of a single ivermectin treatment of calves 3 weeks after turnout was studied in animals which were turned out early on contaminated pasture and in calves which were turned out late on mown pasture. a single ivermectin treatment 3 weeks after early turnout did not prevent heavy helminth infections. however, such single treatment of calves 3 weeks after a late turnout on mown pasture ... | 1986 | 3788029 |
| efficacy of ivermectin in a topical formulation against induced gastrointestinal and pulmonary nematode infections, and naturally acquired grubs and lice in cattle. | efficacy of ivermectin in a topical formulation was evaluated in cattle against adult gastrointestinal and pulmonary nematode infections (experiment 1, n = 24), the 2nd- and 3rd-stage larvae of hypoderma spp (experiment 2, n = 12), and the biting louse damalinia bovis (experiment 3, n = 12). nematode infections were induced and grubs and lice were naturally acquired. treatments consisted of a single dose of ivermectin in a topical formulation of 200, 500, or 1,000 micrograms/kg of body weight in ... | 1986 | 3789500 |
| efficacy of oxfendazole as administered by intraruminal injection to naturally infected calves. | oxfendazole, formulated into a 22.5% suspension, was administered by intraruminal injection to cattle at the rates of 0, 1.125, 2.25, 4.50, and 6.75 mg/kg of body weight. in total, 50 naturally infected calves were used, with 10 animals being allocated to each of the 5 treatment groups on the basis of pretreatment counts of nematode eggs per gram of feces. all animals were necropsied 7 days after treatment. the trial was done between december 1983 and january 1984, with the animals kept on concr ... | 1986 | 3954213 |
| serological studies of parasitized cattle. i. complement--fixing activity of serial serum samples. | complement-fixation (cf) tests with sonicated aqueous extracts of adult forms of five species of gastrointestinal nematodes as antigens have been made on serial biweekly bleedings from two groups of parasitized calves grazing on infected pastures during the 1963 or 1964 seasons. three of these nematode species, cooperia oncophora, ostertagia ostertagi and nematodirus helvetianus, were found in large numbers in most of these animals. the calves were negative serologically before being placed on p ... | 1966 | 4226342 |
| on the survival of overwintering bovine gastrointestinal nematode larvae during the subsequent grazing season. | large numbers of overwintering nematodirus helvetianus were shown to survive on maritime marshland pastures throughout the ensuing grazing season, while the numbers of ostertagia ostertagi and cooperia oncophora declined rapidly after the first few weeks. it was concluded that pastures carrying heavy overwintering residual infections, particularly of n. helvetianus, may be unsafe for susceptible cattle at any time during the following grazing season. | 1969 | 4237295 |
| on the development of gastrointestinal parasitism in bovine yearlings. | a comparative study on the development of osteragia ostertagi, cooperia oncophora and nematodirus helvetianus in 15-month-old yearlings and three-month-old calves demonstrated that yearlings have considerably greater resistance to gastrointestinal parasitism than calves. this was manifested by the establishment of smaller worm burdens, marked stunting of worms and a markedly lower worm egg output in the yearlings. the characteristic marked rise in egg counts observed in calves a few weeks after ... | 1970 | 4249092 |
| on the persistence of infective ostertagia ostertagi, cooperia oncophora and nematodirus helvetianus on pastures. | by grazing parasite-free susceptible calves on naturally infected paddocks for eighteen day periods, nematodirus helvetianus was shown to survive over two winters on marshland pastures under maritime climatic conditions in three successive years although the numbers surviving the second winter in two of the three years were low. climatic conditions of below normal temperatures and little snowfall would appear to have a detrimental effect on the survival of nematodirus over a second winter althou ... | 1972 | 4263911 |
| on the immunological response of young calves to light nematodirus helvetianus infection. | infecting parasite-free eight week old calves with 8,000 infective nematodirus helvetianus larvae did not modify appreciably their response to a later heavy field challenge with n. helvetianus, ostertagia ostertagi and cooperia oncophora, although two of six animals did have smaller nematodirus burdens. | 1973 | 4270440 |
| overwintering of bovine gastrointestinal nematodes in southwestern ontario. | several steers, reared in isolation until approximately six months of age, were placed on a small isolated enclosed pasture from late spring to late fall of 1970, 1971 and 1972. the pasture was left vacant and unused during the winters and early springs. the pasture had been used in previous years by cattle, and in the late spring of 1970 was grazed by cattle know to be passing gastrointestinal nematode eggs in their feces. the steers were slaughtered periodically, and the prevalence of nematode ... | 1974 | 4272963 |
| the effects of anthelmintic treatments on the development of gastrointestinal parasitism in calves. | fortnightly treatment of susceptible calves with 1-tetramisole during the first two months of continuous exposure to pastures residually heavily-infected with ostertagia ostertagi, cooperia oncophora and nematodirus helvetianus did not prevent the development of clinical parasitic gastroenteritis, although the infections were not as severe as in nontreated calves. development of resistance in treated calves was manifested by significantly smaller numbers of cooperia eggs in utero (which were ref ... | 1974 | 4274819 |
| on the natural seeding of marshland pastures with bovine gastrointestinal parasites. | by placing parasite-free calves in paddocks grazed by infected animals for 18 day periods at various times during the previous season it was shown that eggs of ostertagia ostertagi, cooperia oncophora and nematodirus helvetianus deposited on pastures from early july to october of one year were able to survive in the maritime area of canada over winter either as eggs and/or larvae and contribute to residual infections on these pastures the following spring. the greatest deposition and/or survival ... | 1974 | 4274825 |
| efficacy of cambendazole against naturally occurring nematodirus helvetianus and cooperia oncophora infections in calves. | | 1974 | 4429241 |
| inhibited development of ostertagia ostertagi, cooperia oncophora, and nematodirus helvetianus in parasite-free calves grazing fall pastures. | | 1974 | 4842852 |
| observations on the transmission of nematodirus helvetianus to calves at pasture. | | 1972 | 5072577 |
| critical trials on the efficacy of thiabendazole against ostertagia ostertagi, cooperia oncophora, and nematodirus helvetianus. | | 1968 | 5650475 |
| variability of resistance of calves to acquisition of infection by nematodirus helvetianus. | | 1966 | 5915323 |
| investigations into the free-living phase of the life-cycle of nematodirus helvetianus. | | 1966 | 6008294 |
| efficacy of ivermectin in oral paste formulation against immature gastrointestinal and pulmonary nematodes in cattle. | the anthelmintic efficacy of ivermectin in oral paste formulation was evaluated against the 4th-stage larvae of 8 gastrointestinal nematodes and the common lung-worm in 14 experimentally inoculated calves. two groups consisting of 7 calves each were formed by restricted randomization on body weight. the infective larvae were given orally to the animals on a staggered schedule so that the parasites were in the 4th larval stage when the animals were treated. one group was given vehicle paste, and ... | 1984 | 6547278 |
| further tests of activity of levamisole on ostertagia ostertagi in dairy calves with notes on overwinter survival of gastrointestinal helminths on pasture. | two controlled tests were conducted in 1981 and 1982 in dairy calves on the university of kentucky research farm to determine activity of the bolus formulation of levamisole given at the dose rate of 8 mg/kg against naturally occurring infections of ostertagia ostertagi. removal efficacies of mature o ostertagi were 98% in the 1981 test (3 treated and 3 nontreated calves) and 94% in the 1982 test (7 treated and 8 nontreated calves). against immature ostertagia spp, removal efficacies were 100% a ... | 1983 | 6625330 |
| the effects of the use of the morantel sustained release bolus system on calves grazing a highly contaminated pasture in the netherlands. | the efficacy of the morantel sustained release bolus system for the control of parasitic gastroenteritis in calves was evaluated in the netherlands. the effect of bolus administration to calves, either on may 1 at the beginning of the summer grazing season or on june 12 after the pasture was mown for silage, was determined in respect of liveweight gain, faecal worm egg output, serum pepsinogen values and worm burdens. in addition, pairs of tracer calves were turned out with each group every four ... | 1983 | 6684356 |
| anthelmintic efficiency of ivermectin against naturally acquired bovine gastrointestinal nematodes. | ivermectin, one of the new avermectin group of anthelmintics, was more than 99 per cent effective in removing all stages of ostertagia ostertagi including inhibited larvae, and adult trichostrongylus axei when administered to cattle orally at 100 microgram/kg body-weight or subcutaneously at 100 and 200 microgram/kg body-weight. high efficacy (> 98.6 per cent) was also obtained against adults and inhibited larvae of cooperia oncophora at 100 microgram/kg orally or 200 microgram/kg by subcutaneou ... | 1980 | 6893775 |
| population build up of gastrointestinal nematode infections in ewes and lambs on pasture grazed by calves in the previous year. | the development of trichostrongylid infections was studied in ewes, lambs and tracer lambs grazing a pasture which has been used by calves in the previous year. treatment with fenbendazole of the ewes two days before they were turned out to pasture virtually prevented infections with trichostrongylid species characteristic for sheep. significant burdens of ostertagia leptospicularis, cooperia oncophora and nematodirus helvetianus were found. an increased pasture infectivity level compared to spr ... | 1982 | 7079602 |
| the seasonal incidence of helminth parasites of cattle in the eastern transvaal lowveld. | two helminth-free tracer calves were exposed to natural helminth infestation of a farm in the eastern transvaal lowveld for one month. on a nearby farm calves grazed with the herd for at least 3 months before slaughter so that the cumulative worm burden could be determined. the gastro-intestinal parasites increased markedly after rain. the major species and order or prevalence were: cooperia pectinata, cooperia punctata, haemonchus placei and oesophagostomum radiatum; minor species were bunostom ... | 1982 | 7175905 |
| persistence on pasture of the infective larvae of nematodes parasitizing maine dairy cattle. | yearling calves infected with ostertagia ostertagi, cooperia oncophora, and nematodirus helvetianus were allowed to graze on a 0.8 ha pasture plot contaminated during june and august 1977. in june 1978, the plot was subdivided into 10 subplots of equal size. grazing in 5 of these plots was allowed, each for 1 month, during june, july, august, september, and october by groups of 2 parasite-free 16-week-old calves. the procedure was repeated in 1979 with the remaining 5 subplots. each group of cal ... | 1980 | 7224300 |
| seasonal occurence of infective nematode larvae on irrigated pasture grazed by cattle in california. | during the period extending from dec 1, 1975, to dec 22, 1976, 3 distinct peaks in the concentration of infective nematode larvae on pasture forage were detected by use of helminth-free tracer calves. two of these peaks, 1 occurring in the spring and 1 in the fall, consisted mainly of ostertagia ostertagi and cooperia sp. it is concluded that these 2 peaks can be anticipated annually and constitute unsafe periods of grazing. the 3rd peak was comprised largely of haemonchus placei and cooperia sp ... | 1981 | 7271041 |
| 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 ... | 1980 | 7465164 |
| 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 ... | 1995 | 7571270 |
| nematode burdens and productivity of grazing cattle treated with a prototype sustained-release bolus containing ivermectin. | one hundred and twenty four-month-old hereford-friesian cross heifers weighing from 88 to 130 kg were divided into two equal groups. one group acted as a control with each animal receiving one placebo bolus, the other animals received one prototype intraruminal sustained-release bolus designed to deliver approximately 8 mg ivermectin/day for 100 to 120 days. the boluses were administered the day before turnout in mid-may. each group was grazed separately for 167 days on pastures contaminated wit ... | 1994 | 7871690 |
| identification and isolation of a 19.7 kda ostertagia ostertagi specific antigen and evaluation of its potential for immunodiagnosis. | ostertagia ostertagi adult worm extracts were analysed by western blotting using sera from calves experimentally infected with o. ostertagi and cooperia oncophora. strong differences in antigen recognition were noticed, even between animals from the same group. two ostertagia specific antigens with apparent molecular mass of 19.7 (ooa19.7) and 20.7 kda (ooa20.7) were identified. one of them (ooa19.7) was purified by three subsequent chromatographic steps, i.e. gelfiltration, ion-exchange and rev ... | 1994 | 7928070 |
| effectiveness of doramectin for treatment of experimentally induced gastrointestinal tract larval nematode infections in calves. | anthelmintic efficacy of doramectin, a macrocyclic lactone of the avermectin family, was evaluated against larval parasitic nematodes in calves. the investigational product was given sc at a dosage of 0.2 mg/kg of body weight to 10 calves infected 6 days previously with third-stage larvae of the genera haemonchus, ostertagia, cooperia, and nematodirus. ten additional calves with identical larval exposure were given saline solution sc also at 6 days after inoculation, and served as the nonmedicat ... | 1994 | 7944021 |
| antigenic analysis of dictyocaulus viviparus by use of test-positive bovine sera. | an antigen extract of dictyocaulus viviparus was analyzed by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the antigen-recognition patterns of serum antibody from cattle not infected, cattle infected with d viviparus, and cattle with unknown history of d viviparus were analyzed by the use of elisa and western blotting techniques. cross-reactive antibody-recognition patterns were determined by comparing western blots of d viviparus-positive sera with blots of d viviparus-n ... | 1994 | 7998700 |
| 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 ... | 1994 | 8192257 |
| 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 ... | 1993 | 8236735 |
| 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 ... | 1993 | 8236736 |
| comparison of three enzyme immunoassays for diagnosis of dictyocaulus viviparus infection. | three enzyme-linked immunosorbent assays (elisa) that detect antibodies against dictyocaulus viviparus in cattle were compared for sensitivity, specificity and seroconversion after primary infection. these assays were (i) an indirect elisa with crude somatic antigens from adult d. viviparus (ca-elisa), (ii) an indirect elisa with purified antigens (sa-elisa) isolated from somatic antigens of adult d. viviparus and (iii) a competition elisa with antigen purified with anion chromatography in combi ... | 1993 | 8249247 |
| 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 ... | 1993 | 8442334 |
| epizootiology of ostertagia ostertagi in cow-calf production systems in the american midwest. | the most common gastrointestinal nematodes found in cattle in the midwest are ostertagia ostertagi and cooperia oncophora. other parasites include haemonchus placei, bunostomum phlebotomum and nematodirus helvetianus. parasite numbers are generally low in this region, as indicated by fecal egg counts and tracer calf worm recoveries, and the numbers of parasites decrease as one travels farther north. this decrease in parasite numbers also corresponds to a similar reduction in the prevalence of cl ... | 1993 | 8484220 |
| 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 ... | 1996 | 8916402 |
| 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 ... | 1996 | 9017870 |
| 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 ... | 1996 | 9024867 |
| efficacy of doramectin for treatment of experimentally induced infection with gastrointestinal nematodes in calves. | to determine the efficacy of injectable doramectin against experimentally induced infections with adult and larval (l4) stages of gastrointestinal nematodes in calves. | 1997 | 9055975 |
| nematocidal efficacy of eprinomectin, delivered topically, in naturally infected cattle. | to assess the nematocidal efficacy of eprinomectin in naturally infected cattle. | 1997 | 9185967 |
| 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 ... | 1997 | 9187034 |
| evaluation of an elisa for the routine diagnosis of dictyocaulus viviparus infections in cattle. | an enzyme-linked immunosorbent assay (elisa) that detects antibodies against dictyocaulus viviparus in experimentally and naturally infected cattle was evaluated for its sensitivity, specificity, the moment of seroconversion and persistence of the anti-d. viviparus response and precision. the first three parameters were compared with those of an indirect haemagglutination assay (iha). specificity and sensitivity of both assays were assessed in sera collected from calves experimentally infected w ... | 1997 | 9195719 |
| use of cloned excretory/secretory low-molecular-weight proteins of cooperia oncophora in a serological assay. | the potential of cooperia oncophora excretory/secretory (es) proteins as antigens in a serological assay which aims to establish exposure levels in cattle was assessed. es proteins were analyzed by one- and two-dimensional polyacrylamide gel electrophoresis and immunoblotting. the n-terminal domains of two es proteins were sequenced, and the corresponding cdnas were cloned. two cdnas, designated coes14.0 and coes14.2, were expressed in escherichia coli. the recombinant proteins were tested in an ... | 1997 | 9196182 |
| isoelectric focusing of soluble proteins in the characterization of species and isolates of nematodirus (nematoda: trichostrongyloidea). | isoelectric focusing was performed on extracts from nematodirus spathiger, nematodirus filicollis, nematodirus helvetianus, and 3 geographic isolates of nematodirus battus. gender-specific differences were noted within species; however, the overall protein profile of each species and isolate was distinct and reproducible and allowed unequivocal differentiation. a coefficient of similarity (sm) for males of each species and isolate was calculated, and a dendrogram, based on evaluation of sm by th ... | 1997 | 9379295 |
| 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 ... | 1997 | 9477498 |
| differences in the second internal transcribed spacer of four species of nematodirus (nematoda: molineidae). | 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 t ... | 1998 | 9512998 |
| an abattoir survey of gastrointestinal nematode infections in cattle in the central highlands of kenya. | the gastrointestinal tracts of 672 crossbred cattle were obtained from various abattoirs in kiambu district, kenya from august 1992 to july 1993, and examined for the presence of gastrointestinal nematodes. eight nematode species were found in 583 (86.8%) of the animals. the nematodes were, in order of prevalence: haemonchus placei (67.0%), cooperia pectinata (53.0%), cooperia punctata (41.7%), oesophagostomum radiatum (38.4%), trichostronglyus axei (24.3%), nematodirus helvetianus (19.6%), tric ... | 1998 | 9778778 |
| 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 ... | 1999 | 10386433 |
| use of a pre-selected epitope of cathepsin-l1 in a highly specific peptide-based immunoassay for the diagnosis of fasciola hepatica infections in cattle. | a peptide-based indirect elisa to detect cattle antibodies against fasciola hepatica was developed and evaluated for its sensitivity and specificity. an immunogenic antigen released in vitro by f. hepatica was purified. after purification the sequence of the first 20 n-terminal aa of this protein showed considerable homology with cathepsin l-like proteinase. based on its homology with cathepsin-l1, we further focused on this protein for diagnostic purpose. predicted b-cell epitopes of cathepsin- ... | 1999 | 10404262 |
| efficacy of an ivermectin controlled-release capsule against some rarer nematode parasites of sheep. | a controlled trial was conducted to evaluate the efficacy of the intraruminal ivermectin controlled-release capsule (crc) (ivomec maximizer cr capsule for sheep, merial ltd.) against induced incoming third-stage larvae and established adult infections with some rarer gastrointestinal nematode parasites of sheep. twenty-one worm-free lambs were allocated by restricted randomisation based on body weight within sex to one of the following treatments: unmedicated control, ivermectin crc given on day ... | 2000 | 10714467 |
| relationships of nematodirus species and nematodirus battus isolates (nematoda: trichostrongyloidea) based on nuclear ribosomal dna sequences. | nuclear ribosomal sequence data from the internal transcribed spacers (its-1 and its-2), 5.8s subunit, and regions of the 18s and 28s genes were used to investigate sequence diversity among geographic samples of nematodirus battus, and to infer phylogenetic relationships among nematodirus species. phylogenetic analysis of these data yielded strong support for relationships among species, depicting nematodirus helvetianus and nematodirus spathiger as sister-taxa and a clade of these 2 species and ... | 2000 | 10864259 |
| 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 ... | 2000 | 11097305 |
| 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 ... | 2001 | 11780839 |
| [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 ... | 2003 | 12592928 |
| experimental infections of calves with the nematode, nematodirus helvetianus. | | 1953 | 13050880 |
| the effect of hephenium embonate on egg production in nematodirus helvetianus and other gastrointestinal nematodes in catle. | | 1960 | 14439896 |
| therapeutic and persistent efficacy of moxidectin 1% nonaqueous injectable formulation against natural and experimentally induced lung and gastrointestinal nematodes in cattle. | four controlled trials were conducted to evaluate the therapeutic and persistent efficacy of a new moxidectin formulation (moxidectin 1% nonaqueous injectable) against nematode parasites in cattle. this injectable moxidectin formulation, given as a single subcutaneous injection at a dose rate of 0.02 ml/kg bw to provide 0.2 mg moxidectin/kg bw, was highly efficacious (>90-100%) against larval and/or adult stages of many species of nematodes in cattle including, dictyocaulus viviparus, ostertagia ... | 2004 | 15063941 |
| parasites of domestic and wild animals in south africa. xlv. helminths of dairy calves on dry-land kikuyu grass pastures in the eastern cape province. | successive pairs of approximately 4-month-old friesland bull calves, raised under worm-free conditions, were exposed to helminth infection for 14 days on dry-land kikuyu grass pastures at 28-day to monthly intervals, on a coastal farm in a non-seasonal rainfall region of the eastern cape province. with the exception of one pair of calves exposed for 28 days, this procedure was repeated for 28 consecutive months from december 1982 to march 1985. the day after removal from the pastures one calf of ... | 2004 | 15732456 |
| efficacy of a topical formulation of eprinomectin against endoparasites of cattle in new zealand. | two controlled studies involving 24 cattle were conducted in new zealand to determine the efficacy of a topical, non-flammable formulation of eprinomectin against induced and naturally acquired nematode infections. in trial 1, nematode infections were induced on day -5 with third-stage larvae of cooperia spp., haemonchus contortus, ostertagia ostertagi and trichostrongvlus colubriformis so that the nematodes would be at the fourth larval stage when the cattle were treated. in trial 2, cattle had ... | 1997 | 16031938 |
| the efficacy of an ivermectin/closantel injection against experimentally induced infections and field infections with gastrointestinal nematodes and liver fluke in cattle. | three studies were performed to test the efficacy of an ivermectin/closantel injection (200 microg/kg(-1) ivermectin and 5 mg/kg(-1) closantel) in cattle. two were experimentally induced infections of ostertagia ostertagi, cooperia oncophora and fasciola hepatica in calves, and the third had natural field infections in cattle with several species of gastrointestinal nematodes and f. hepatica. in the two studies with artificial infections, four groups of 8 calves were used. all calves were infect ... | 2008 | 18562120 |
| autumn nematodirus helvetianus infections in calves. | | 2011 | 21257567 |
| comparative efficacy of trichlorphon and trichlorphon/ivermectin combination treatment against anthelmintic-resistant cattle nematodes in argentina. | twenty-four holando argentino male calves were treated orally with 50 mg/kg body weight trichlorphon (tcf); 0.2 mg/kg body weight subcutaneous ivermectin (ivm); a combination of tcf+ivm at the same doses and administration routes; or remained untreated (control group). all calves were necropsied at day 14 post treatment for counting and identification of worms from abomasum, small and large intestines and lungs to determine the absolute efficacy (controlled efficacy test) for each treatment. usi ... | 2011 | 21739380 |
| therapeutic efficacy of eprinomectin extended-release injection against induced infections of developing (fourth-stage larvae) and adult nematode parasites of cattle. | the therapeutic efficacy of eprinomectin in an extended-release injection (eri) formulation was evaluated against induced infections of developing fourth-stage larval or adult gastrointestinal and pulmonary nematodes of cattle in a series of six studies under two identical protocols (three each for developing fourth-stage larvae or adults) conducted in the usa, germany or the uk (two studies at each location, one per stage). each study initially included 16 nematode-free cattle. the cattle were ... | 2012 | 23273929 |
| nematode burdens of pastured cattle treated once at turnout with eprinomectin extended-release injection. | the efficacy of eprinomectin in an extended-release injection (eri) formulation was evaluated against infections with third-stage larvae or eggs of gastrointestinal and pulmonary nematodes in cattle under 120-day natural challenge conditions in a series of five studies conducted in the usa (three studies) and in europe (two studies). for each study, 30 nematode-free (four studies) or 30 cattle harboring naturally acquired nematode infections (one study) were included. the cattle were of various ... | 2012 | 23273928 |
| the efficacy of eprinomectin extended-release injection against naturally acquired nematode parasites of cattle, with special regard to inhibited fourth-stage ostertagia larvae. | the efficacy of eprinomectin in an extended-release injection (eri) formulation in the treatment of cattle harboring naturally acquired nematode populations (including inhibited nematodes) was evaluated. five studies were conducted under a similar protocol in the usa, the uk, and in germany. all study animals were infected by grazing naturally contaminated pastures. the adequacy of pasture infectivity was confirmed by examining tracer calves prior to allocation and treatment of the study animals ... | 2012 | 23273781 |
| nematodes of the large intestine of the european bison of the białowieza national park. | the present study was conducted on 31 males and females of the european bison, eliminated during the winter seasons 2007-2011 in the białowieza primeval forest, poland. the caeca of 14 free-ranging bison, aged from 3 months up to 16 years, the most favorable infection site for the large intestine nematodes, were investigated during the winter of 2007/2008. the parasitological autopsies of the large intestines of 9 free-ranging bison aged from 5 months up to 10 years as well as 9 bison kept in th ... | 2012 | 23094330 |
| reevaluation of efficacy against nematode parasites and pharmacokinetics of topical eprinomectin in cattle. | a study was conducted to confirm the efficacy of topical eprinomectin against nematodes and to evaluate the pharmacokinetics in cattle prevented from having physical contact with other cattle and from self-grooming. sixteen male brown swiss calves were infected with larvae of recently isolated nematode parasites. inoculation was scheduled so that the nematodes were expected to be adults at the time of treatment. animals were blocked based on pretreatment body weight and randomly allocated to the ... | 2012 | 22638921 |
| effects of age, sex, lactation and social dominance on faecal egg count patterns of gastrointestinal nematodes in farmed eland (taurotragus oryx). | the eland is a large african antelope that can be bred in a temperate climate, under similar conditions and production systems as cattle. however, knowledge of parasites in farmed elands outside the area of their native habitat is still limited, and information concerning factors that influence these parasites is lacking. therefore, faecal samples from an entire herd of elands, including calves and adult females and males, were examined monthly over a one year period. almost 84% of the animals w ... | 2015 | 26277201 |
| control trial and fecal egg count reduction test determinations of nematocidal efficacies of moxidectin and generic ivermectin in recently weaned, naturally infected calves. | an anthelmintic efficacy study was performed with young, naturally infected beef-type calves obtained at local farms. presumably, the study calves had been recently weaned and had not been treated with a parasiticide prior to study acquisition. after blocking the 24 study calves in accordance with calculated cooperia spp epg counts, the calves were randomly allocated within each block to one of four treatment groups, resulting in 6 animals per treatment group (untreated controls, topical ivermec ... | 2013 | 23380250 |
| seasonal occurrence of infective nematode larvae in california high sierra pastures grazed by cattle. | worm-free holstein calves were used to assess the seasonal variation in numbers of nematode infective larvae on herbage at 2 commercial cow-calf ranches in the sierra nevada mountains. both ranches used herefords as their basic breed. one ranch near sattley, california, is at an elevation of approximately 1,500 m above sea level, whereas the study area on the 2nd ranch near susanville is at an elevation of approximately 1,250 m above sea level. worm-free tracer calves were allowed to graze for a ... | 1984 | 24049905 |
| towards finding effective indicators (diarrhoea and anaemia scores and weight gains) for the implementation of targeted selective treatment against the gastro-intestinal nematodes in lambs in a steppic environment. | the effective application of targeted selective treatment (tst) against gastro-intestinal nematodes depends on the accurate identification of those animals in need of anthelmintic treatment. finding cost and labour effective measures to identify such animals is paramount. this study tested the efficacy of three indicators on lambs in a farm in eastern algeria: anaemia score (famacha(©)), diarrhoea score (disco) and weight gain. these were contrasted against traditional parasitological infection ... | 2012 | 22270033 |