Publications

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
efficacy of fenbendazole-medicated feed blocks against gastrointestinal nematode infections in calves.	an anthelmintic trial was conducted to determine the efficacy of fenbendazole (fbz) incorporated into two types of feed blocks given daily for 3 or 10 days to calves naturally parasitized with gastrointestinal nematodes. each treated calf consumed 5 mg of fbz/kg of body weight. the fbz was greater than 99% effective in removing adults of haemonchus contortus, ostertagia ostertagi, o lyrata, cooperia punctata, c pectinata, c onchophora, trichostrongylus axei, bunostomum phlebotomum, and oesophago ...	1987	3605803
[effects of various disinfectants on the development and survival possibilities of the pre-parasitic stages of ostertagia ostertagi, cooperia oncophora and ascaris suum].	eleven disinfectants varying in chemical composition and containing active chlorine, phenol, cresol, sodium or potassium hydroxide, quaternary ammonium compounds, glutaraldehydes or paraformaldehyde were tested for their lethal effect on eggs and infective larvae of ostertagia ostertagi and cooperia oncophora and non-embryonated and embryonated eggs of ascaris suum. suspensions of all tested stages were mixed with the disinfectants in the concentrations recommended by the manufacturer and with d ...	1987	3617021
the epidemiology of ostertagia ostertagi and other gastrointestinal nematodes of cattle in louisiana.	the epidemiology of ostertagia ostertagi and other gastrointestinal nematodes in yearling beef cattle was examined in each of 2 successive years. during each year 50 head of newly weaned beef calves were given a single dose of thiabendazole and then placed on experimental pastures. twenty-four of the animals were designated for monthly slaughter (n = 2) and analysis of worm population characteristics and 25 were designated for blood and faecal collection and for weighing. parasite-free tracer ca ...	1987	3670895
the regulation of ostertagia ostertagi populations in calves: the effect of past and current experience of infection on proportional establishment and parasite survival.	a mathematical model of the parasitic phase of the life-cycle of ostertagia ostertagi in calves is described. the model is used in the re-analysis of previously published data from a long-term trickle infection experiment in which groups of calves were infected daily with graded doses of 3rd-stage (l3) larvae. the results of the analysis are consistent with the hypothesis that the observed changes in the intensity of infection in the calves were the result of a decline in the proportional establ ...	1987	3696770
the regulation of ostertagia ostertagi populations in calves: density-dependent control of fecundity.	the decline in faecal egg counts, characteristic of calves which have been experimentally infected with ostertagia ostertagi, is analysed using a mathematical model in which parasite fecundity is assumed to be an inverse function of both the duration and intensity of infection. the model incorporates a description of the frequency distribution of mature parasites between hosts (which is less over-dispersed than is usual for many other helminth infections). the model provides a good overall descr ...	1987	3696771
a mathematical model of the population biology of ostertagia ostertagi in calves and yearlings.	a mathematical model of the population biology of ostertagia ostertagi is described. the model assumes that the natural control and regulation of parasite numbers is mediated by four processes: the effect of climate on the development and survival of the free-living stages; changes in the rate of establishment of the infective larvae, and density-dependent variations in parasite survival and fecundity. the model is used to compare the course of the infection in two groups of calves. one group is ...	1987	3696772
population biology of ostertagia ostertagi and anthelmintic strategies against ostertagiasis in calves.	five chemoprophylactic or chemotherapeutic strategies against bovine ostertagiasis are compared using a mathematical model of the population biology of ostertagia ostertagi. the model offers a means of screening novel strategies prior to their further investigation in the field. under conditions of climate and management typical of many regions in northern temperate europe, the model indicates that all of the tested prophylactic strategies will result in a profound reduction in the intensity of ...	1987	3696773
the development and mortality of the non-infective free-living stages of ostertagia ostertagi in the field and in laboratory culture.	a deterministic model of the population biology of the non-infective free-living phase of ostertagia ostertagi is described and tested. a comparison of field and laboratory studies indicates that the pre-infective larvae of o. ostertagi spend about twice as long in this phase in the field as in laboratory culture (13 days and 7 days respectively at 15 degrees c), and that the subsequent transition (i.e. second moult) to the infective phase also proceeds at a much slower rate (about 10 times less ...	1986	3714308
serum antibody response to soluble extract of the third-larval stage of ostertagia ostertagi in cattle.	serum igg, igm, and iga antibody responses against l3 antigens of ostertagia ostertagi were monitored by enzyme-linked immunosorbent assay (elisa) after one, two or multiple sequential inoculations of this nematode in calves. following the first infection, antibody levels did not change. after a second inoculation, igg increased significantly (p less than 0.05) after 2 months. igg was not significantly increased 1 month after challenge inoculation. igm and iga antibody levels did not change foll ...	1986	3716175
maximum-likelihood estimates of the mortality and migration rates of the infective larvae of ostertagia ostertagi and cooperia oncophora.	we present an analysis of the survival and migration rates of the infective (l3) stages of ostertagia ostertagi and cooperia oncophora. although the majority of laboratory studies show that the survival of the l3 stage depends upon temperature, moisture and the age of the larvae, a simple mathematical model of larval demography, in which their mortality and migration rates are held constant, provides as good agreement between observed and predicted larval counts as models in which these rate pro ...	1986	3737245
response to transplanted adult ostertagia ostertagi in calves.	plasma pepsinogen levels became elevated in groups of recipient calves immediately after transplant with adult ostertagia ostertagi. these rises occurred in both previously parasite-naive calves and in calves which had experienced prior infection terminated with an anthelmintic either seven or 21 days before transplant. from the results it appears that adult o ostertagi play a significant role in the elevated plasma pepsinogen levels associated with bovine ostertagiasis.	1986	3738234
effects of transfer of ostertagia ostertagi between northern and southern u.s.a. on the pattern and frequency of hypobiosis.		1986	3744677
strategic deworming for spring-calving beef cow/calf herds.	strategic application of an anthelmintic was tested during the 1982 grazing season as part of the continued study of the epidemiology of beef cattle parasitism in central missouri. forty hereford and hereford x simmental cow/calf pairs were assigned to 2 treatment groups. the 20 cow/calf pairs in group 1 were nonmedicated controls. after calving in mid-march, the 20 cows in group 2 were drenched with a 10% suspension of the anthelmintic fenbendazole (10 mg/kg of body weight). ten cow/calf pairs ...	1986	3759614
lymphocyte blastogenic responses of calves experimentally infected with ostertagia ostertagi.	twelve 9-week-old calves were divided into four groups; two groups were maintained helminth-free as controls and the other groups were given ostertagia ostertagi infective-stage larvae (l3) orally. one group received 100,000 l3 as a single inoculum and the other group received l3 in increasing dosages at weekly intervals for 8 consecutive weeks. the blastogenic responses to concanavalin a (con a), phytohemagglutinin (pha), and a soluble larval antigen from o. ostertagi (sla) of peripheral blood ...	1986	3788025
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
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
ostertagiosis in a white-tailed deer due to ostertagia ostertagi.		1987	3820419
further studies on the response to transplanted adult ostertagia ostertagi in calves.	calves infected by surgical transplantation of adult ostertagia ostertagi had raised levels of plasma pepsinogen and those in which the largest number of worms established also had elevated plasma gastrin concentrations. despite the elevated plasma pepsinogen values, the abomasal ph of the animals did not change significantly, and there was no significant difference in the percentage establishment of adult parasites in calves previously infected with o ostertagi third stage larvae and those whic ...	1987	3823628
pathogenesis of simulated natural infections with ostertagia ostertagi in calves.	the possibility of a mucosal hypersensitivity reaction and its relationship to the pathogenesis of simulated natural infections with ostertagia ostertagi were studied in calves. four groups of 4 calves each were used. one group was used as noninfected control; a 2nd group was given increasing doses of infective larvae; a 3rd group was given increasing doses of larvae and these were removed by succeeding treatment with an anthelmintic; and a 4th group was given an initial dose of larvae which was ...	1987	3826866
persistence of dead ostertagia ostertagi in the abomasal mucosa following anthelmintic treatment.	anthelmintic trails, conducted with albendazole, fenbendazole and ivermectin for efficacy against gastrointestinal nematodes, principally inhibited early fourth larval stages of ostertagia ostertagi in naturally infected cattle. cattle wee slaughtered seven to 20 days after treatment. o ostertagi was the predominant abomasal nematode recovered with occasional small numbers of haemonchus species and trichostrongylus axei. control calves uniformly had very large o ostertagi infections, primarily e ...	1985	3838393
efficacy of ivermectin against gastrointestinal nematodes in cattle in south africa.	the efficacy of ivermectin administered at 200 micrograms/kg was evaluated against induced infestations of 5 gastrointestinal nematode species in cattle. results were analysed by the modified non-parametric method and a "a" class (more than 80% effective in more than 80% of the treated animals) was achieved with an oral drench and subcutaneous injection against the third and fourth larval and adult stages of bunostomum phlebotomum, cooperia spp. (c. pectinata and c. punctata), haemonchus placei, ...	1985	3839020
efficacy of the tris-salt of 2 [(methoxycarbonylamino)-[2-nitro-5-(n-propylthio) phenylimimo] methylamino] ethane sulfonic acid against inhibited larvae of ostertagia ostertagi.	the tris-salt of 2-[(methoxy-carbonylamino) - [2-nitro-5-(n-propylthio) phenylimimo] methylamino] ethane sulfonic acid (mca) was evaluated against naturally acquired gastrointestinal parasitism in cattle during spring in louisiana to determine efficacy of the compound against inhibited early 4th-stage larvae (el4) of ostertagia ostertagi. forty-three crossbred yearling beef heifers were grazed together on contaminated pastures between mar 1 and apr 18, 1984. on april 17, 3 of the 43 heifers were ...	1985	3917240
ostertagia ostertagi: excretory secretory chemotactic substance from infective larvae as cause of eosinophil locomotion.	the infective (third stage) larva of ostertagia ostertagi produced an excretory secretory substance that is chemotactic for bovine eosinophils. the eosinophil chemotactic substance was present in supernatants of larval cultures within 6 hr of incubation in eagle's minimum essential medium containing 25 mm n-2-hydroxyethylpiperazine-n'-2-ethanesulfonic acid. the substance responsible for eosinophil chemotaxis has activity in small amounts, a molecular weight (mw) greater than 2000, and is heat la ...	1986	3943588
seasonal comparisons of anthelmintic activity of levamisole pour-on in cattle in the usa.	anthelmintic activity of a pour-on formulation of levamisole, applied during warm weather (16 degrees to 36 degrees c) at 10 mg/kg bodyweight, was evaluated in groups of naturally parasitised calves. this activity was compared to that obtained in similar groups of calves treated in the winter (-4 degrees to +7 degrees c). controlled efficacy of the pour-on formulation was determined for each season by comparing mean worm burdens in treated calves sacrificed seven to nine days after treatment to ...	1986	3946069
efficacy of an albendazole feed formulation against bovine gastrointestinal nematodes including arrested larvae of ostertagia ostertagi.	the efficacy of an albendazole feed premix formulation was compared with that of an albendazole drench suspension for control of gastrointestinal nematodes in 31 beef cattle. the premix (11 cattle) and drench suspension (9 cattle) were found to have similar efficacies at a dosage of 7.5 mg/kg of body weight. when compared with controls (11 cattle), both formulations caused significant (p less than 0.05) reductions in worm counts with an efficacy of 98% or greater against adult haemonchus placei, ...	1986	3946888
immunosuppression of lymphocyte blastogenesis in cattle infected with ostertagia ostertagi and/or trichostrongylus axei.	twenty 4-month-old calves were infected with o ostertagi and/or t axei and the responses to phytolectins were evaluated. whole blood cultures were incubated with phytohemagglutinin (pha), concanavalin a (con a) and pokeweed mitogen (pwm). the blastogenic response was determined by tritiated thymidine uptake with results presented as counts per minute (cpm), stimulation indices (si) and a mononuclear cell responsive index determined by dividing the phytomitogen induced cpm by the absolute mononuc ...	1986	3962170
the effect of experimental ostertagia ostertagi infections in stabled milking cows on egg output, serum pepsinogen levels, antibody titres and milk production.	two trials with stabled milking cows were carried out. in the first trial, cows were either experimentally infected with ostertagia ostertagi larvae or served as naturally-infected controls. in the second trial, cows were treated the same as in the first trial, but in addition half of the number of cows of each group were treated with oxfendazole before the trial started. the results showed that experimental infection influenced ostertagia egg output, host serum pepsinogen levels and anti-ostert ...	1985	4002600
effects of season and physical condition on the gastrointestinal helminth community of white-tailed deer from the texas edwards plateau.	eighty-six adult female white-tailed deer, odocoileus virginianus (zimmermann), collected over a 12-mo period in the texas edwards plateau, harbored six species of nematodes (haemonchus contortus, gongylonema pulchrum, oesophagostomum venulosum, ostertagia ostertagi, cooperia sp., and apteragia odocoilei), and two cestodes (moniezia sp. and taenia hydatigena). the patterns of distribution of the three common species of gastrointestinal helminths (h. contortus, o. venulosum, and g. pulchrum) were ...	1985	4032624
trichostrongyle larval populations on herbage from grazed and ungrazed cattle pastures in south west scotland.	in the course of studies on the control of bovine parasitic gastroenteritis in south west scotland using a morantel sustained release bolus the populations of trichostrongyle infective larvae on herbage were monitored over a two-year period. from the results of the herbage analysis and the worm burdens in parasite naive tracer calves introduced at the end of 18 months, it was clear that considerable numbers of infective larvae of ostertagia ostertagi and cooperia oncophora survived for at least ...	1985	4035086
synergistic influence of ostertagia ostertagi and trichostrongylus axei on ostertagia ostertagi larval inhibition and abomasal lesions in cattle.	parasite-free 4-month-old calves were inoculated with ostertagia ostertagi and/or trichostrongylus axei followed 6 weeks later by increasing doses of o ostertagi for 8 weeks. clinical signs of parasitism, fecal egg counts, and plasma pepsinogen concentrations were monitored, and gross lesions and parasite burdens were determined postmortem. clinical signs of parasitism were not observed and weight gains were not affected in experimentally infected calves. in calves infected with o ostertagi, mea ...	1985	4037502
experimentally induced ostertagiosis in rabbits inoculated with ostertagia ostertagi of bovine origin.	weanling specific-pathogen-free rabbits were orally inoculated with 50,000 ostertagia ostertagi 3rd-stage infective larvae cultured from bovine feces and were killed 42 days after inoculation. two preliminary trials were done, using conventionally reared weanling rabbits inoculated with 2,500, 5,000, and 50,000 o ostertagi 3rd-stage larvae and dexamathasone in 1 of the trials; the rabbits were killed 14 and 28 days after inoculation. fecal egg counts were monitored, and worm burdens were determi ...	1985	4062028
chemotactic factors for eosinophils in soluble extracts of l3 stages of ostertagia ostertagi.		1985	4066145
effect of ostertagia ostertagi on lamb performance and cross resistance to o circumcincta.	fifteen worm-free lambs (two-and-a-half to three months or four to four-and-a-half months old) were infected with 3500 or 4000 ostertagia ostertagi larvae on five days each week for six weeks, and their performance compared to that of controls. eleven lambs were killed after eight weeks and four were challenged with o circumcincta to determine whether any cross resistance had developed. a feature of the o ostertagi infection was the considerable variation in response. overall liveweight gain was ...	1985	4070787
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
the effects of age and previous infection on the development of gastrointestinal parasitism in cattle.	an age resistance in cattle to establishment of infection with cooperia oncophora was not demonstrated. cattle exposed to a heavy infection for the first time at approximately 15 months of age were as susceptible to establishment of infection as 3 to 4 month old calves, but stunting of worms and inhibition of ovulation did occur in the older animals, possibly due to a rapid development of resistance as a result of sensitization by a previous extremely light infection. an age resistance in cattle ...	1968	4234780
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 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
the development, clinical signs and economic losses of gastrointestinal parasitism in feeder cattle on irrigated and non-irrigated dikeland and upland pastures.	investigations were carried out over three grazing seasons with parasitized and treated (control) steers on irrigated and non-irrigated upland and dikeland pastures. the stocking rate in each paddock was adjusted by either adding or removing animals so as to maintain as uniform a sward and rate of grazing as possible. animals were weighed on and off the pastures and fortnightly during the grazing seasons. during the first grazing season clinically normal steers shedding low numbers of gastrointe ...	1972	4263919
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
abomasal nematodes in cattle in ontario.	during 1970, 93 abomasa from cattle in ontario were examined, and from 63 of these abomasa nematode species of the genera ostertagia, haemonchus and/or trichostrongylus axei were recovered. the abomasa were from cattle six months to two years of age and were collected either from the postmortem room at the ontario veterinary college or from two abattoirs near guelph. the numbers of worms per abomasum were estimated and their genera were identified from a one-twentieth volume of the washings and ...	1974	4272952
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
inhibited development in ostertagia ostertagi infections--a diapause phenomenon in a nematode.		1974	4418146
the survival of infective larvae of ostertagia ostertagi and cooperia oncophora in hayloft-dried grass.		1974	4432682
trichostrongylus askivali dunn, 1964, and ostertagia ostertagi (stiles, 1892) in white-tailed deer (odocoileus virginianus) of the southeastern united states.		1974	4436752
studies on the survival of eggs and infective larvae of ostertagia ostertagi and cooperia oncophora in herbage.		1974	4475530
studies on arrested development of ostertagia ostertagi and cooperia oncophora.		1974	4478097
the survival of eggs and infective larvae of ostertagia ostertagi and cooperia oncophora in solid cattle manure and urine.		1974	4478790
effect of temperature on development of the free-living stages of ostertagia ostertagi.		1972	4641869
the development and symmetry of the vulval flap of ostertagia ostertagi.		1972	4661361
host induced effects on the vulval flap of ostertagia ostertagi.		1972	4661362
effect of temperature on survival of the free-living stages of ostertagia ostertagi.		1972	4674485
ostertagia ostertagi: protective immunity in calves. the development in calves of a protective immunity to infection with ostertagia ostertagi.		1973	4691928
inhibition of development: variation within a population of ostertagia ostertagi.		1973	4727894
predatory activity of nematode trapping fungi against the larvae of trichostrongylus axei and ostertagia ostertagi: a possible method of biological control.		1973	4735716
distribution of ostertagia ostertagi infective larvae on pasture herbage.		1973	4748245
first report of human infection with haemonchus contortus, ostertagia ostertagi, and marshallagia marshalli (family trichostrongylidae) in iran.		1973	4760647
studies on the influence of lime, formalin, formic acid, and ammonium persulphate on the eggs and larvae of ostertagia ostertagi and cooperia oncophora in liquid cattle manure.		1973	4798421
ostertagia ostertagi: establishment of patent infections in calves by intravenous inoculation.		1974	4813202
nonenzymic histochemistry of bovine abomasal tissue infected with ostertagia ostertagi.		1974	4821117
the effect of corticosteroid treatment on the development of inhibited ostertagia ostertagi larvae.		1974	4830990
inhibited development of ostertagia ostertagi, cooperia oncophora, and nematodirus helvetianus in parasite-free calves grazing fall pastures.		1974	4842852
studies on the survival of infective larvae of ostertagia ostertagi and cooperia oncophora in silage grass containing formic acid.		1974	4844325
studies on the survival of eggs and infective larvae of ostertagia ostertagi and cooperia oncophora in liquid cattle manure.		1974	4858506
studies on the bionomics of eggs and infective larvae of ostertagia ostertagi and cooperia oncophora in soil.		1974	4858507
develpoment and survival of infective larvae of the cattle nematode, ostertagia ostertagi.		1971	5102817
functional morphology and histochemistry of structural proteins of the genital cone of ostertagia ostertagi, with a comparison of the genital cones of other ostertagia common in cattle in the united states.		1971	5105969
on experimental transmission of ostertagia ostertagi (stiles, 1892) ransom, 1907, to sheep.		1971	5145205
host-induced effects on the size and body proportions of ostertagia ostertagi (stiles, 1892) ransom, 1907, a nematode parasite of cattle.		1971	5157152
adult worms as a factor in the inhibition of development of ostertagia ostertagi in the host.		1971	5161202
inhibition of ostertagia ostertagi at the early fourth larval stage. i. the seasonal incidence.		1969	5348694
inhibition of ostertagia ostertagi at the early fourth larval stage. ii. the influence of environment on host or parasite.		1969	5348695
the development of the parasitic stages of ostertagia ostertagi.		1969	5381123
the effect of cortisone on populations of ostertagia ostertagi of uniform age.		1969	5386283
the regulation of egg output by ostertagia ostertagi in calves infected once only.		1969	5390574
observations on the faecal egg count of calves naturally infected with ostertagia ostertagi.		1969	5390577
some observations on the worm burdens of calves infected daily with ostertagia ostertagi.		1969	5393715
the effect of cortisone on the worm burdens of calves infected daily with ostertagia ostertagi.		1969	5393716
the regulation of egg output by ostertagia ostertagi in calves infected once only.		1969	5393717
observations on the faecal egg count of calves naturally infected with ostertagia ostertagi.		1969	5393718
the effect of oral parbendazole against ostertagia ostertagi and cooperia punctata in experimentally infected calves.		1970	5411561
the regulation of population of ostertagia ostertagi in calves.		1970	5534089
the effect of host resistance on the development of the vulval flap in ostertagia ostertagi.		1967	5625912
[biology and ecology of pre-parasitic development stages of ostertagia ostertagi and cooperia oncophora (nematoda, trichostrongylidae) in view of the epidemiology of trichostrongyloidiasis of cattle].		1967	5631855
[biology and ecology of the preparasitic development stages of ostertagia ostertagi and cooperia oncophora (nematoda, trichostrongyloidea) with reference to the epidemiology of cattle trichostrongyloidiasis].		1967	5632511
critical trials on the efficacy of thiabendazole against ostertagia ostertagi, cooperia oncophora, and nematodirus helvetianus.		1968	5650475
[experimental vaccination of calves with irradiated larvae of ostertagia ostertagi and cooperia oncophora].		1969	5796074
experimental ostertagia ostertagi infections in calves: parasitology and pathogenesis of a single infection.		1966	5961410
experimental infections of ostertagia ostertagi in calves: results of two regimens of multiple innoculations.		1967	6065936
some aspects of resistance to animal and human helminths. acquired resistance and its effect on populations of ostertagia ostertagi.		1967	6066882
regulation of egg output of populations of ostertagia ostertagi.		1967	6069727
controlled test of the efficacy of the feed premix formulation of crufomate on the parasites of the gastrointestinal tract and lungs of dairy calves.	activity of the feed premix formulation (m-1839) of crufomate against helminths of the gastrointestinal tract and lungs of cattle was determined in a controlled test. eight calves were treated and 7 were nontreated. the dosage rate of crufomate was 17 mg of active drug/kg of body weight daily for 3 consecutive days. removal activity was high against mature cooperia oncophora (99%) and c punctata (96%) and immature cooperia spp (87%). removal of mature ostertagia ostertagi was 68%. the removal of ...	1982	6213184
therapeutic and prophylactic efficacy of morantel when administered directly into the rumen of cattle on a continuous basis.	the efficacy of morantel tartrate when administered on a continuous basis directly into the rumen/reticulum of cattle, either by a cannula or from a specially designed device, was evaluated against gastrointestinal parasites under laboratory conditions. in two experiments the continuous infusion of morantel at rates between 0.26 and 1.04 mg/kg body weight per day using a peristaltic pump was highly efficacious in both preventing the establishment of infections and removing established infections ...	1983	6225238
experimental and natural infection of calves with bunostomum phlebotomum.	an experiment was conducted to determine the efficiency of a method of experimental infection of weaner beef calves with bunostomum phlebotomum and to compare such infection with that established by natural infection. six calves, maintained on a concrete-floored pen, were inoculated with b. phlebotomum l3 by placing the larval inocuulum, in small volume, in the outer chamber of the ear while the animal was restrained for 18 min. inoculation doses of 20, 30, 40, 50, 60, and 80 thousand l3 were us ...	1983	6229089
enzyme-linked immunosorbent assay for the detection of antibodies to hypoderma bovis in cattle.	an adaptation of the enzyme-linked immunosorbent assay has been shown to detect antibodies in the circulation of cattle infected with hypoderma bovis. strong positive reactions were obtained from all infected cattle, even those which harboured only one larva. a strong cross reaction was observed in sera taken from cattle infected with h lineatum, but not in cattle infected with fasciola hepatica or ostertagia ostertagi.	1983	6344168
[efficacy of albendazole as a pellet formulation against ostertagia ostertagi and cooperia oncophora in experimentally infected calves].		1984	6370654
controlled and clinical evaluations of the anthelmintic activity of a levamisole pour-on formulation against gastrointestinal nematodes in cattle.	beef-type calves (n = 107) with naturally occurring helminth infections were used in a series of 3 controlled experiments to study the anthelmintic activity of a new pour-on formulation of levamisole. in the 1st experiment, the efficacy of a single treatment of levamisole pour-on at a rate of 10 mg/kg of body weight was determined, using a placebo pour-on in a similar volume as a control. in the 2nd experiment, calves were treated with levamisole pour-on at doses 0 (nontreated control), 7.5, 10, ...	1984	6377988
experimental studies on the interaction between infections of ostertagia leptospicularis and other bovine ostertagia species.	experimental infections of calves were carried out with either isolates of predominantly ostertagia ostertagi, pure o. leptospicularis or a mixed isolate of equal numbers of both these species. the total worms established on day 21 for the mixed species from a total inoculum of 100 000 infective larvae, was 1.2 times greater than from 100 000 larvae of the o. ostertagi isolate and 3.3 times that of the pure o. leptospicularis isolate. the increased establishment in the mixed inoculum referred to ...	1984	6441374