| occurrence of gastrointestinal parasites in georgia cattle. | a survey of gastrointestinal nematodes in georgia cattle was conducted from 1968 through 1973 from actual worm counts from viscera of 145 slaughtered beef cattle or from egg counts made from fecal samples from 3,273 beef and 100 dairy cattle. beef cattle were grouped as calves, yearlings, and cows. dairy cattle were grouped as calves, replacement heifers, and cows. results of fecal examinations positive; 99.5, 99.3, 99.6, and 41.2% of the calves, yearlings, drylot calves, and cows, respectively, ... | 1975 | 123711 |
| controlled test of anthelmintic activity of levamisole administered to calves via drinking water, subcutaneous injection, or alfalfa pellet premix. | a controlled test of the activity of 3 formulations of levamisole, at the dose level of approximately 8 mg/kg, against naturally occurring infections of gastrointestinal parasites and lungworms was made in 24 calves allotted to 4 groups of 6 calves each. levamisole was administered to group i calves in the drinking water, to group ii calves by subcutaneous injection, and to group iii calves by feeding alfalfa pellets mixed in corn silage; group iv calves were nontreated controls. group i calves ... | 1975 | 125055 |
| effect of albendazole on gastrointestinal parasites of cattle. | the efficacy of albendazole in removing gastrointestinal nematodes and tapeworms was studied in 16 treated and 16 untreated (control) beef calves. the anthelmintic was administered as an oral drench at a dose level of 5 ml/45.5 kg of body weight (5 mg/kg). percentage of efficacy against the various genera was: trichostrongylus axei, oesophagostomum radiatum, and moniezia-100.0; haemonchus placei, cooperia spp, and trichostrongylus colubriformis - greater than 99.0; ostertagia ostertagi -98.3; an ... | 1977 | 145816 |
| anthelmintic efficacy of albendazole in cattle: comparison of critical and controlled tests. | twelve calves were experimentally inoculated with 6 species of gastrointestinal nematodes and the liver fluke, fasciola hepatica. six calves were administered albendazole at 10 mg/kg of body weight, and the drug efficacy was determined by critical and controlled tests. albendazole was only 74% effective against haemonchus contortus (cambendazole-resistant strain), 99 to 100% effective against ostertagia ostertagi, trichostrongylus colubriformis, cooperia oncophora, and oesophagostomum radiatum, ... | 1977 | 334003 |
| thyroxine and thyroxine-binding proteins in trichostrongylus colubriformis-infected sheep. | | 1977 | 409617 |
| [efficacy of mebendazole in sheep experimentally invaded with larvae of haemonchus contortus and trichostrongylus colubriformis in relation to the results of clinical examination]. | a group of six lambs at the age of two months and of the average weight of 13 kg were invaded with the larvae haemonchus contortus and trichostrongylus colubriformis; the course of invasion was compared with that in a group of four control lambs. in regular ten-day intervals, some hematological indices, proteinemia. sgot and sgpt activities, glucose level, sodium and potassium were studied in blood samples; at the same time egg elimination was observed in excrement samples. the invasion intensit ... | 1978 | 416548 |
| avermectins, new family of potent anthelmintic agents: efficacy of the b1a component. | when given to sheep as a single oral dose at 0.1 mg/kg, the b(1a) component of the avermectins caused a reduction of >95% in the numbers of haemonchus contortus, ostertagia circumcincta (including inhibited l(4) larvae), trichostrongylus axei, trichostrongylus colubriformis, cooperia oncophora, and oesophagostomum columbianum. when given to cattle as a single oral dose at 0.1 mg/kg, avermectin b(1a) was >95% effective in reducing the numbers of haemonchus placei, ostertagia ostertagi (including ... | 1979 | 464563 |
| the rate of recovery of intestinal morphology following anthelmintic treatment of parasitised sheep. | sixteen sheep which had previously been infected with ostertagia circumcincta were dosed with 4000 trichostrongylus colubriformis larvae/day for four weeks, then given anthelmintic and killed at intervals thereafter. histological examination of the small intestine showed that two to three weeks were required for restoration of a normal mucosal architecture. | 1979 | 472483 |
| the effect of single and divided dose administration on the efficacy of fenbendazole against adult stages of benzimidazole resistant sheep trichostrongylids. | sheep infected with benzimidazole resistant strains of haemonchus contortus and trichostrongylus colubriformis were used to compare the anthelmintic efficacy of fenbendazole given as a single dose or administered in a divided dose regime over five days. statistical analysis showed no significant difference between the two methods of administration for h contortus. on the other hand, divided dose fenbendazole was significantly less effective than single doses against adult t colubriformis at dose ... | 1979 | 472493 |
| the anthelmintic efficacy of albendazole against fasciola hepatica and benzimidazole resistant strains of haemonchus contortus and trichostrongylus colubriformis in sheep. | the anthelmintic efficacy of albendazole (methyl [5-(propylthio) - 1h - benzimidazole -2 -yl] carbamate) against immature and adult fasciola hepatica and against standardised strains of benzimidazole resistant haemonchus contortus and trichostrongylus colubriformis was evaluated in experimentally infected sheep. a single intrarumenal treatment of dose rates of 3.8 and 7.6 mg/kg was ineffective against immature (six weeks old) f hepatica. dose rates of 5.7 and 7.6 mg/kg reduced the number of matu ... | 1979 | 472494 |
| investigations of 'transfer factor' activity in immunity to ostertagia circumcincta and trichostrongylus colubriformis infections in sheep. | | 1979 | 489234 |
| the effect of antiserum to eosinophils and susceptibility and acquired immunity of the guinea-pig to trichostronglyus colubriformis. | there is much experimental evidence to suggest that eosinophils are important in resistance to parasitic infection. we tested this hypothesis by treating guinea-pigs with rabbit anti-eosinophil serum (aes) and determining the effect of treatment on susceptibility and acquired immunity to trichostrongylus colubriformis. the treatment markedly reduced the number of eosinophils in peripheral blood and in the small intestine. the number of t. colubriformis present after initial infection and after a ... | 1979 | 500132 |
| [helminth fauna of syrian cattle]. | in this work the stomach and the small intestine of 34 and the large intestine of 4 more cattle were examined. 91,17% of the examined cattle (31 in 34 animals) had infected the stomach and/or the small intestine by parasites. 14 kinds of nematodes were found. the average intensity of infection of the stomach was higher than that of the small intestine. with the exception of higher infection in 3 stomachs and 2 small intestines the intensity of infection in all other cases was from small to mediu ... | 1979 | 453633 |
| the activity of levamisole against benzimidazole resistant haemonchus contortus and trichostrongylus colubriformis. | | 1979 | 516343 |
| efficacy of febantel in sheep experimentally infected with five species of gastrointestinal nematodes. | the anthelmintic activity of the guanidine derivative febantel was tested in a total of 76 experimentally infected lambs in two control tests. doses of 5.0 and 7.5 mg per kg body-weight were administered orally against fourth and pre-adult fifth or adult stages of haemonchus contortus, ostertagia circumcincta, trichostrongylus colubriformis, b unostomum trigonocephalum and oesophagostomum columbianum. the efficacy was between 98.5 and 100 per cent. the drug was well tolerated. | 1978 | 155340 |
| the efficacy of fenbendazole and albendazole against immature and adult stages of benzimidazole-resistant sheep trichostrongylids. | the efficacy of two recently introduced benzimidazole anthelmintics, albendazole and fenbendazole, was determined for six-day, 10-day and adult stages of resistant strains of haemonchus contortus and trichostrongylus colubriformis. albendazole, at 3.8 mg/kg reduced h contortus worm counts by 92.4, 70.8 and 67.1 per cent while fenbendazole, at 5.0 mg/kg, reduced worm burdens by 51.7, 95.5 and 93.4 per cent against six-, 10- and 25-day-old parasites respectively. for t colubriformis, the correspon ... | 1979 | 504798 |
| 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 |
| trichostrongylus colubriformis and ostertagia circumcincta resistant to levamisole, morantel tartrate and thiabendazole: occurrence of field strains. | field strains of trichostrongylus colubriformis and ostertagia circumcincta, designated pf4 and pf5 respectively, were recovered from a farm on which the sole use of levamisole over a preceding 12 year period led to the development of anthelmintic resistance. the results of field observations and preliminary critical trials in both merino and crossbred sheep showed that both species have varying degrees of resistance to three major anthelmintics; levamisole, morantel tartrate and thiabendazole. ... | 1979 | 504797 |
| resistance of nematode eggs to the ovicidal activity of benzimidazoles. | eggs of benzimidazole-resistant haemonchus contortus and trichostrongylus colubriformis are resistant to the ovicidal activity of benzimidazoles. the possiblity is raised of using this as a simple screen for detection of resistance in nematodes of domesticated animals. | 1977 | 560037 |
| instability of benzimidazole resistance in nematode eggs. | the resistance of the eggs of benzimidazole resistant haemonchus contortus and trichostrongylus colubriformis is not stable and will decrease in the absence of drug challenge. dosing animals harbouring resistant h contortus with either thiabendazole or mebendazole selects for nematodes producing thiabendazole resistant eggs. the eggs of a thiabendazole selected strain of h contortus were more resistant to thiabendazole, parbendazole and oxibendazole but less resistant to cambendazole and mebenda ... | 1978 | 569353 |
| [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 |
| the effect of route of administration on the anthelmintic efficacy of benzimidazole anthelmintics in sheep infected with strains of haemonchus contortus and trichostrongylus colubriformis resistant or susceptible to thiabendazole. | observations of erratic anthelmintic activity of fenbendazole against known standardised thiabendazole-resistant strains of haemonchus contortus and trichostrongylus colubriformis in sheep were investigated. fenbendazole at a dose rate of 10 mg/kg body weight was administered by oral, intra-ruminal or intra-abomasal routes, and was most effective against both resistant strains following intra-ruminal administration. in addition thiabendazole, oxibendazole, fenbendazole, parbendazole and mebendaz ... | 1977 | 577045 |
| levels of benzimidazole resistance in haemonchus contortus and trichostrongylus colubriformis recorded from an egg hatch test procedure. | a method of using commercially available benzimidazole anthelmintics in an egg hatch test, to record levels of resistance is described. the test shows that a side-resistance is present to all the benzimidazole anthelmintics tested against both haemonchus contortus and trichostrongylus colubriformis after selection with thiabendazole. additional selection on the field resistant strain of h contortus with thiabendazole showed increased levels of resistance to all the compounds tested while similar ... | 1978 | 581912 |
| the dose response of several benzimidazole anthelmintics against resistant strains of haemonchus contortus and trichostrongylus colubriformis selected with thiabendazole. | dose response lines for eight benzimidazole anthelmintics and thiophanate were determined, using standardised strains of thiabendazole selected and resistant haemonchus contortus and trichostrongylus colubriformis. against h contortus, thiophanate, thiabendazole, parbendazole and oxibendazole were inactive. mebendazole was inactive at dose rates of 6.26 and 12.5 mg/kg, although significant activity occurred at 25 mg/kg. fenbendazole, cambendazole, oxfendazole and albendazole demonstrated signifi ... | 1978 | 581913 |
| cellular changes in the intestinal lymph of sheep infected with the enteric nematode, trichostrongylus colubriformis. | some changes produced in the cell populations of intestinal lymph by infection with the enteric nematode, trichostrongylus colubriformis, were studied in sheep regularly re-infused with all discharged lymph. lymphocyte traffic through the intestinal lymphatic duct was reduced until day 35 of primary infection, mainly due to the absence of lymphocytes with smaller cell volumes, but was increased two-fold after day 70 and in immune sheep. antigen-reactive lymphocytes in blood and lymph were assaye ... | 1977 | 564178 |
| parasites of domestic and wild animals in south africa. vii. helminths in pigs slaughtered at the pretoria municipal abattoir. | a total of 52 pigs slaughtered at the pretoria municipal abattoir over a period of 1 year was examined for parastitic helminths. twenty-six of these pigs were marketed by farmers and 26 by speculators. of the pigs marketed by farmers 73,1% were found to be infested:--30,8% with ascaris suum, 65,4% with ascarops strongylina, 3,8% with metastrongylus apri, 26,9% with oesophagostomum spp., 15,4% with trichostrongylus colubriformis and 15,4% with trichuris suis. all the pigs marketed by speculators ... | 1978 | 568230 |
| parasites of domestic and wild animals in south africa. viii. helminths in pigs kept under semi-intensive conditions. | the seasonal incidence of nematode infestations in pigs raised under semi-intensive conditions was determined by the monthly slaughter of 2--4 tracer pigs exposed to infestation in an earthernfloored pen for periods of 1 or 2 months. although worm burdens were generally small, ascarops strongylina appeared to be more prevalent from november to march than during the other months of the year. once ascaris suum became established in the pen nearly all the pigs became infested. the number of worms n ... | 1978 | 568231 |
| protein metabolism. 6. trichostrongylus colubriformis: skeletal protein catabolism in primary and secondary infections of the guinea pig. | | 1978 | 627280 |
| rehabilitation in lambs after infection with trichostrongylus colubriformis. | | 1977 | 606714 |
| protein metabolism. 5. trichostrongylus colubriformis: changes of host body mass and protein synthesis in guinea pigs with light to heavy infections. | | 1978 | 627277 |
| vaccination against the nematode trichostrongylus colubriformis. iii. some observations on factors influencing immunity to infection in vaccinated guinea-pigs. | | 1978 | 631977 |
| studies on the role of histamine and 5-hydroxytryptamine in immunity against the nematode trichostrongylus colubriformis. iv. inhibition of the expulsion of worms transplanted into the duodenum of immune guinea pigs. | significant numbers of fourth larval stage trichostrongylus colubriformis from sheep donors are expelled from the small intestine of t. colubriformis-immune guinea pigs within 8 h of transplantation into this organ. this model system for the immune expulsion of gastrointestinal nematode parasites was used in the current experiments to examine the effect of drugs recently shown to modify the release of histamine. the experiments showed that worm expulsion was inhibited by the beta-adrenergic agon ... | 1978 | 631916 |
| the anthelmintic efficacy of non-benzimidazole anthelmintics against benzimidazole resistant strains of haemonchus contortus and trichostrongylus colubriformis in sheep. | the anthelmintic efficacy of 6 non-benzimidazole compounds and thiabendazole against standardised, benzimidazole resistant strains of h. contortus and t. colubriformis in sheep was determined using a controlled test. all compounds were administered intraruminally at their recommended therapeutic dose rates and 4 of the compounds were also assessed at half their recommended therapeutic dose rates. levimisole at a dose of 6.4 mg/kg body weight, morantel at 4.4 mg/kg and 8.8 mg/kg, naphthalophos at ... | 1978 | 655966 |
| the response of lambs to vaccination at weaning with irradiated trichostrongylus colubriformis larvae: segregation into 'responders' and 'non-responders'. | | 1978 | 631981 |
| immunoglobulin metabolism in sheep infected with the small intestinal nematode trichostrongylus colubriformis. | radiotracer techniques were used to compare the kinetics of igg1 and igg2 metabolism in sheep (1) prior to parasite exposure, (2) during an initial patent infection with trichostrongylus colubriformis, and (3) during continuous exposure to the parasite when the animals were exhibiting resistance. plasma concentrations of igg1, igg2, iga and igm were also monitored throughout the experiment. plasma igg1 concentration increased significantly during the development of resistance and maintained this ... | 1978 | 678229 |
| flow and protein composition of intestinal lymph in sheep infected with the enteric nematode, trichostrongylus colubriformis. | a study of immunoglobulin and albumin concentrations and the flow of intestinal lymph was made in sheep during infection with the parasitic nematode, trichostrongylus colubriformis. observations were made on uninfected worm-free sheep, on worm-free sheep undergoing primary infection and on immune sheep undergoing challenge infection. the flow of intestinal lymph and the concentrations of igg1, igg2 and igm in intestinal lymph and igg2 and igm in blood plasma remained relatively constant during ... | 1978 | 678230 |
| trichostrongylus colubriformis infection of guinea pigs: genetic basis for variation in susceptibility to infection among outbred animals. | two lines of guinea-pigs, whose susceptibilities to infection with the parasitic nematode trichostrongylus colubriformis differ significantly, have been established. this difference is probably based on genetically determined differences between the ability of members of each line to bring about immune expulsion of the parasite. | 1978 | 652388 |
| recovery of nematodes from ruminants by migration from gastro-intestinal ingesta and mucosa gelled in agar: preliminary report. | when gastro-intestinal ingesta and mucosa containing larvae or adult haemonchus contortus, ostertagia circumcincta. trichostrongylus colubriformis, strongyloides papillosus, nematodirus spathiger, gaigeria pachyscelis, oesophagostomum columbianum or chabertia ovina were suspended in 0,75--1,00% agar gel and incubated in physiological saline, a mean of 93,6% of the helminths migrated from the agar-ingesta or agar-mucosa into the physiological saline. the lowest suitable concentration of agar was ... | 1978 | 704042 |
| immune responses of sheep to the parasitic nematode trichostrongylus colubriformis: infections in thiry-vella loops. | some aspects of the local immune response to nematode infection were examined by introducing fourth-stage trichostrongylus colubriformis larvae into thiry-vella loops in worm-free and t. colubriformis-resistant sheep. approximately 15% of the larvae introduced into the worm-free sheep survived and matured into adult worms, whereas less than 1% survival in resistant sheep. the amount of igg1, igg2, igm and albumin discharged from loops in worm-free but not resistant sheep all increased following ... | 1978 | 666677 |
| studies on the role of histamine and 5-hydroxytryptamine in immunity against the nematode trichostrongylus colubriformis. v. changes in amine levels in the intestine following infection of guinea pigs of different immune status. | a temporal relationship was established between the onset of expulsion of the parasitic nematode trichostrongylus colubriformis from the intestine of both vaccinated and adoptively immunized guinea pigs with a sudden increase in small intestinal mucosal histamine to two or three times pre-infection levels. however, in guinea pigs whose capacity to expel t. colubriformis was inhibited by treatment with anti-lymphocyte serum, mucosal histamine remained at pre-infection levels. the results support ... | 1978 | 640747 |
| thiophanate as a low daily dosage anthelmintic in sheep. | thiophanate administered daily at low dosages reduced nematode faecal egg output, egg hatchability and parasitic worm burdens in treated lambs and ewes. six daily doses of 1 or 3 mg per kg thiophanate (approximately 1/25th to 1/75th of the median therapeutic dose), given to lambs experimently infected with trichostrongylus colubriformis, were partially effective in suppressing faecal egg output and egg hatchability. six doses of 5 mg per kg per day were effective in lambs infected with haemonch ... | 1978 | 695254 |
| trichostrongylus colubriformis: cultivation of free-living stages. | successful cultivation of trichostrongylus colubriformis from hatched first-stage to third-stage larvae was achieved in media containing nctc 135, chick embryo extract, fetal calf serum, and either lactalbumin hydrolysate or freshly prepared baker's yeast extract. medium tc5, containing yeast extract, was the simplest medium with optimal results. cultured third-stage larvae were able to produce patent infections in guinea pigs. | 1978 | 739295 |
| [helminths of birds and mammals from israel. vi. the taxonomy and ecology of trichostrongylid nematodes (author's transl)]. | thirteen species of trichostronglyloid nematodes have so far been recorded from wild birds and mammals in israel and surrounding territories. three species were found in birds: amidostomum fulicae (rudolphi, 1819) in fulica atra l., 1758, a. acutum (lundahl, 1848) in anas crecca l., 1758 and amidostomum sp. in ceryle rudis l., 1758. ten species, 3 of which are new, were found in small mammals: trichostrongylus colubriformis (giles, 1892) in hystrix indica kerr, 1792; tenorastrongylus josephi n. ... | 1975 | 776059 |
| [clinical examination of the blood of roe deer (capreolus capreolus l.) and fallow deer (dama dama l.) naturally invaded by parasites]. | roe-deer (capreolus capreolus l. -- five animals) and fallow deer (dama dama l. -- eleven animals) of both sexes and at different age were subject to blood examination. the deer were killed in several preserves in bohemia during autumn and winter shootings in two years. the following blood values were determined: erythrocyte count, leucocyte count, hemoglobin content, hematocrit values, mcv, mch, mchc, white blood picture, total protein, its fractions (albumin, alpha-, beta-, and gamma-globulin) ... | 1975 | 809892 |
| failure to demonstrate involvement of prostaglandins in the immune expulsion of trichostrongylus colubriformis from the intestine of guinea pigs. | the intraduodenal injection of synthetic prostaglandins did not lead to the expulsion of trichostrongylus colubriformis from the intestine of guinea pigs. treatment of immune guinea pigs with aspirin and indomethacin failed to inhibit the expulsion of a challenge infection with this nematode. these results suggest that in this infection, unlike nippostrongylus brasiliensis infection in the rat, prostaglandins do not play an important role in the immune expulsion of the parasite from the intestin ... | 1977 | 838518 |
| in vitro and in vivo studies on the ovicidal activity of fenbendazole. | the in vitro ovicidal activity of fenbendazole against eggs of ostertagia ostertagi, haemonchus contortus and trichostrongylus colubriformis was observed using different concentrations of active principle. the optimum concentration for ovicidal activity is evidently 0.5 ppm fenbendazole. a further increase in concentration results in a decrease in activity which is probably due to physical causes. ovicidal activity of the product is assessed by the proportion of non embryonated eggs as well as e ... | 1978 | 749077 |
| parasitism (trichostrongylus colubriformis and eimeria ninakohlyakimovae) in sheep: relationship between wool fiber diameter changes and feed conversion efficiency. | twenty-five lambs, 5 months of age, were used to compare the infection pressure of trichostrongylus colubriformis with that of eimeria ninakohlyakimovae. effects of the parasitic infection pressure were assayed by determining body weight gains, feed conversion efficiencies, and wool fiber diameter changes (reflecting changes in protein metabolism) in lambs fed a good ration and those given a marginal diet (dehydrated alfalfa pellets). significant differences in weight grains or feed conversion e ... | 1977 | 879585 |
| comparison of the kinetics of expulsion of trichostrongylus colubriformis from previously uninfected, reinfected, and vaccinated guinea pigs. | | 1977 | 886417 |
| degree-day concept in development of infective larvae of haemonchus contortus and trichostrongylus colubriformis under constant and cyclic conditions. | | 1977 | 911077 |
| the efficacy of febantel on gastrointestinal nematodes in sheep. | febantel (bay h 5757, rintal) is a broad-spectrum anthelmintic of a new type. a single oral dose of 5 mg/kg is fully effective against larval and adult stages of haemonchus contortus, trichostrongylus colubriformis, oesophagostomum columbianum, ostertagia circumcincta and bunostomum trigonocephalum in sheep. | 1978 | 749080 |
| trichostrongylus colubriformis: host factors influencing the transfer of immunity in guinea pigs using mesenteric lymph node cells. | | 1977 | 862700 |
| the anthelmintic efficacy of fenbendazole against thiabendazole-resistant strains of haemonchus contortus and trichostrongylus colubriformis in sheep. | the anthelmintic efficacy of fenbendazole (methyl 5-(phenylthio)-2-benzimidazole carbamate) was tested in sheep against standardised strains of hcaemonchus contortus and trichostrongylus colubriformis, known to be resistant to thiabendazole (ld90 for thiabendazole against h ontortus was 200 mg/kg bodyweight and against t colubriformis was 150 mg/kg). fenbendazole at dose rates of 5, 10 and 20 mg/kg per os reduced total worm counts in h contortus infected sheep by 66, 90 and 100 per cent respecti ... | 1976 | 968192 |
| efficacy of albendazole against gastrointestinal nematodes of cattle. | forty-five calves with artificial and pasture-acquired nematode infections were medicated with albendazole at dose levels of 0, 2.5, 5.0, or 10 mg/kg of body weight. a dose level of 2.5 mg/kg removed at least 99% of adult trichostrongylus axei, trichostrongylus colubriformis, cooperia oncophora, and bunostomum phlebotomum. burdens of haemonchus contortus, strongyloides papillosus, and ostertagia ostertagi were reduced 79, 88, and 97%, respectively. at a dose level of 5.0 mg/kg, at least 95% of a ... | 1976 | 999077 |
| basophil leucocytes in cutaneous hypersensitivity reactions in nematode-infected guinea-pigs. | cutaneous hypersensitivity reactions were elicited in guinea-pigs infected with the parasitic nematode trichostrongylus colubriformis by injecting them with a crude extract of t. colubriformis fourth-stage larvae. the reaction was characterized by early oedema and pronounced cellular infiltration, initially with neutrophils but later with mononuclear cells, basophils and variable numbers of eosinophils. because basophils have been implicated as effector cells in the protective immune response of ... | 1976 | 1016128 |
| subclinical trichostrongylosis in growing lambs produced by continuous larval dosing. the effect on performance and certain plasma constituents. | three groups of eight-four-month-old worm-free lambs were used to investigate the effect of trichostrongylus colubriformis infection on growth rate, food intake, and concentration of plasma constituents. groups alc and ali were fed ad libitum, the latter being dosed daily with 2500 infective larvae for 14 weeks. lambs in group pf were paired to individuals in group ali and offered the same quantity of food as the infected pair consumed. hypophosphataemia and hypoalbuminaemia developed in ali at ... | 1976 | 1030817 |
| studies on the kinetics of expulsion by guinea-pigs of primary infections with the intestinal nematode parasite trichostrongylus colubriformis. | | 1975 | 1112623 |
| the effect of continuous doses of trichostrongylus colubriformis larvae on the intestinal mucosa of sheep and on liver vitamin a concentration. | eight 7-month-old sheep were dosed continuously with trichostrongylus colubriformis larvae and 4 sheep were killed at 5 and 10 weeks from the commencement of infection. flattening of the mucosa and villous atrophy were commonly present at slaughter, and parasites were often found in superficial channels parallel with the luminal surface. at 10 weeks the mucosa was thickened and highly cellular. leucine aminopeptidase, alkaline phosphatase and maltase activity were reduced in the proximal third o ... | 1975 | 1118182 |
| intestinal pathology associated with trichostrongylus colubriformis infection in sheep: histology. | observations were made on the histology of tissues from the first 6-10 m of the small intestine from both sheep infected with trichostrongylus colubriformis and from uninfected controls. in uninfected animals, and in distal samples from infected lambs, villi were tall and covered by tall columnar epithelium, the intestinal crypts were convoluted and the lamina propria was only moderately cellular. in tissues with sub-total villus atrophy and a convoluted surface, the superficial epithelium was ... | 1975 | 1128919 |
| intestinal pathology associated with trichostrongylus colubriformis infection in sheep: vascular permeability and ultrastructure of the mucosa. | increased permeability of capillaries and venules, labelled with colloidal carbon, was observed in the superficial mucosa of the small intestine of sheep infected with trichostrongylus colubriformis. the labelled vessels were restricted to infected portions of the gut, and the intensity of labelling appeared to be related to density of the worm population. open junctions were seen between endothelial cells in permeable vessels. in moderately atrophic infected intestine, enterocytes were domed ... | 1975 | 1128920 |
| vaccination against the nematode trichostrongylus colubriformis. ii. attempts to protect guinea-pigs with worm acetylcholinesterase. | | 1975 | 1140883 |
| effectiveness of broad spectrum anthelmintics against selected strains of trichostrongylus colubriformis. | a field population of trichostrongylus columbriformis was divided into 4 lines for exposure to selection in the laboratory. the first line was selected with 50 mg/kg thiabendazole, the second with 4 mg/kg morantel tartrate, the third with 50 mg/kg thiabendazole followed by 4 mg/kg morantel tartrate and the fourth line was not selected for drug resistance. following at least 9 generations of selection there was no difference in ld50 or ld95 between the unselected and single selected strains of wo ... | 1978 | 753221 |
| studies of the responses of basophil and eosinophil leucocytes and mast cells to the nematode trichostrongylus colubriformis. i. observations during the expulsion of first and second infections by guinea-pigs. | during expulsion by guniea-pigs of both first and second infections with the intestinal nematode parasite trichostrongylus colubriformis, increased numbers of basophils and eosinophils were present in the bone marrow and blood. in addition, increased numbers of basophils, mast cells and eosinophils, many possessing reduced numbers of cytoplasmic granules, accumulated at the sites of infection. blood eosinophil counts, however, did not show significant changes during the early part of a first inf ... | 1975 | 1159576 |
| studies of the responses of basophil and eosinophil leucocytes and mast cells to the nematode trichostrongylus colubriformis. ii. changes in cell numbers following infection of thymectomised and adoptively or passively immunised guinea-pigs. | the role of the immune response in the generation of the basophilia and eosinophilia found during expulsion of the intestinal nematode parasite, trichostrongylus colubriformis, by guinea-pigs was investigated by studying cell numbers in animals whose immune responsiveness had been modified by thymectomy and adoptive or passive immunisation. basophilia, but not eosinophilia, was depressed in thymectomised guinea-pigs. bone marrow basophil numbers were significantly increased in t. colubriformis-i ... | 1975 | 1195052 |
| studies of the responses of basophil and eosinophil leucocytes and mast cells to the nematode trichostrongylus colubriformis. ultrastructural changes in basophils and eosinophils at the site of infection. | basophil and eosinophil leucocytes infiltrate the small intestinal lamina propria of guinea-pigs infected with the nematode trichostrongylus colubriformis. by comparing the morphology of both cell types at the site of infection with bone marrow and buffy coat cells, it was found that, after entering the lamina propria, basophils developed an electron lucent halo beneath the granule-limiting membrane while the characteristic orderly periodicity of the granules changed to a fibrillar or amorphous ... | 1975 | 1230142 |
| location and distribution of trichostrongylus colubriformis in the small intestine of sheep during the prepatent period, and the development of villus atrophy. | | 1975 | 1141473 |
| haematological changes caused by trichostrongylus colubriformis in lambs fed a dystrophogenic diet. | the effect of trichostrongylus colubriformis on lambs maintained on a ration containing a low level of selenium and on animals receiving vitamin e and se supplementation was investigated. the pathological changes seen in control animals slaughtered at the start of the experiment and in the animals which died during the course of the investigation revealed a high level of nutritional muscular dystrophy (nmd) in the lambs. there were no marked haematological changes in the control or infested shee ... | 1977 | 915893 |
| anthelmintic efficiency of oxfendazole in california lambs. | oxfendazole, methyl 5(6)-phenylsulfinyl-2-benzimidazole carbamate, was given by oral drench (5 mg/kg) to california lambs harboring natural infections of gastrointestinal nematodes. ninety-nine percent of adult ostertagia circumcincta, ostertagia trifurcata, trichostrongylus axei, trichostrongylus vitrinus, trichostrongylus colubriformis, nematodirus filicollis, and nematodirus spathiger were removed by the anthelmintic. | 1977 | 921025 |
| micrometeorological factors involved in development and survival of free-living stages of the sheep nematodes haemonchus contortus and trichostrongylus colubriformis. a review. | | 1975 | 1232063 |
| the survival of ostertagia circumcincta and trichostrongylus colubriformis in faecal culture as a source of bias in apportioning egg counts to worm species. | when cultured alone or concurrently with trichostrongylus colubriformis in sheep faeces, ostertagia circumcincta produced fewer infective larvae per 100 eggs than did t. colubriformis. averaged over five trials 60% of t. colubriformis eggs were recovered as infective larvae while for o. circumcincta the figure was only 39%. this result was observed for two strains of o. circumcincta and was independent of when larvae were harvested from culture (days 6-10 at 25 degrees c). the mortalities of bot ... | 1992 | 1459776 |
| association of blood eosinophilia with the expression of resistance in romney lambs to nematodes. | the dynamics of blood eosinophilia was studied in romney lambs dosed twice weekly with 5000 infective larvae of trichostrongylus colubriformis. a marked rise in blood eosinophil counts of the dosed lambs coincided with the start of the decline of faecal egg counts (fec). eosinophilia was also studied in grazing romney lambs from a breeding programme, based on selection for high or low fec. comparison of the sire groups suggested that the magnitude of the eosinophil response was under genetic con ... | 1992 | 1459790 |
| the effect of adjuvant and specific or non-specific vaccination on development of protective immunity of rabbits against trichostrongylus colubriformis infection. | adult new zealand rabbits were vaccinated subcutaneously with one dose of 100 micrograms adult nematode phosphate buffered saline-soluble proteins (pbs-asp, groups i and ii), a detergent-soluble fraction of adult somatic proteins (ds-asp, group iii) or three doses of 1 mg normal rabbit serum proteins (group iv). injections of the immunogens in groups ii, iii and iv were accompanied with beryllium hydroxide, be(oh)2 as an adjuvant. vaccinated rabbits and also those of group v (naive) were challen ... | 1992 | 1459793 |
| population dynamics of trichostrongylus colubriformis and ostertagia circumcincta in single and concurrent infections. | twenty-one-week-old worm-free pen-reared lambs were infected weekly with either 10,000 t. colubriformis larvae, 5000 o. circumcincta larvae, or with both species (15,000 larvae per week). larval establishment and total worm burdens were estimated after 4, 7, 10 and 13 weeks of infection. faecal egg counts and lamb bodyweights were measured weekly, and numbers of eosinophils in blood were estimated before infection and at weeks 5, 8 and 14. for both species of worms, the dynamics of infection (es ... | 1992 | 1459794 |
| comparison of an indirect haemagglutination assay and an elisa for diagnosing fasciola hepatica in experimentally and naturally infected sheep. | an enzyme-linked immunosorbent assay (elisa) with somatic (s) or excretory-secretory antigens (es) was compared with an indirect haemagglutination assay (iha) for ability to detect antibodies against fasciola hepatica in sheep. the specificity of both assays was determined by testing sera collected from sheep experimentally or naturally mono-infected with fasciola hepatica, haemonchus contortus, ostertagia circumcincta, cooperia curticei, taenia ovis, eimeria spp., trichostrongylus vitrinus, tri ... | 1992 | 1485406 |
| gastrointestinal helminths and lungworms of french dairy goats: prevalence and geographical distribution in poitou-charentes. | a study was conducted on 81 dairy-goat farms in western france. faecal samples were collected once and 31 culled goats were necropsied in order to assess their gastrointestinal and respiratory helminth species, their prevalences and the intensities of infection as well as their geographical distribution in six subregions of the surveyed area. fifteen species of helminth were recovered. the most frequent were muellerius capillaris, trichostrongylus colubriformis and teladorsagia circumcincta with ... | 1992 | 1494857 |
| evaluation of ivermectin against experimental infections of haemonchus contortus and trichostrongylus colubriformis in goats. | fourteen nematode parasite-naïve kids were given a mixed larval inoculum (approximately 17,250 infective larvae) via stomach tube. twenty-two days after infection, the kids were randomly assigned to control and treatment groups of seven animals each. mean eggs per gram for control and treatment groups were 4304 and 5315, respectively. kids in the treatment group were given ivermectin (0.2 mg kg-1) administered by subcutaneous injection. at necropsy, the mean numbers of haemonchus contortus and t ... | 1992 | 1496785 |
| a new anthelmintic assay using rats infected with trichostrongylus colubriformis. | a new anthelmintic assay is described which uses immunosuppressed (60 ppm hydrocortisone acetate in diet) rats infected with the nematode trichostrongylus colubriformis. immunosuppressed rats were infected with 1500 t. colubriformis larvae, treated either orally or subcutaneously on day 14 post-infection and necropsied 4 days after treatment. the worm counts in immunosuppressed control animals averaged 775 worms per rat. a range of benzimidazoles, levamisole hydrochloride, morantel tartrate, 22, ... | 1992 | 1496787 |
| anthelmintic activity of dioxapyrrolomycin. | dioxapyrrolomycin, pyrrolomycin c, pyrrolomycin d, and piericidin c2 produced by uc 11065 were evaluated as anthelmintics. assays used to examine these compounds included effects on the free-living nematode caenorhabditis elegans, ability to clear target nematodes (haemonchus contortus and trichostrongylus colubriformis) from jirds, and clearance of haemonchus contortus from lambs. a crude extract of uc 11065 containing dioxapyrrolomycin, pyrrolomycin c, pyrrolomycin d, and piericidin c2 was act ... | 1992 | 1500366 |
| efficacy of ivermectin delivered from a sustained-release bolus against inhibited early fourth-stage larvae of ostertagia ostertagi and other nematodes in cattle. | the anthelmintic efficacy of ivermectin (ivm) delivered from a sustained-release (sr) bolus was evaluated against natural infections with gastrointestinal tract nematodes in 12 crossbred beef heifers in spring. the 12 calves were randomly allotted to 2 groups of 6 calves each. group-1 calves were treated with an sr bolus designed to deliver 8 mg of ivermectin/d. group-2 calves were nontreated controls. cattle groups were kept in separate concrete-floored pens (grass hay nutrition) and slaughter ... | 1992 | 1524310 |
| the isolation, characterization and cloning of a globin-like, host-protective antigen from the excretory-secretory products of trichostrongylus colubriformis. | an 18-kda component from the excretory-secretory (es) products of adults of trichostrongylus colubriformis was isolated and characterized, and was shown to induce 60-84% protection of guinea pigs from challenge infection following a single intraperitoneal injection. amino-terminal sequence analysis of gel-purified protein enabled oligonucleotides to be synthesized and used to screen a lambda gt10 cdna library made from young adult worm mrna, and to synthesize full-length clones from cdna using t ... | 1992 | 1542314 |
| studies of stage-specific immunity against trichostrongylus colubriformis in sheep: immunization by normal and truncated infections. | sheep immunized with multiple normal infections of 30,000 trichostrongylus colubriformis larvae (t.c. l3) suppressed the fecundity, establishment and survival of adoptively transferred adult worms, showing that these parasites were susceptible to the effects of host immunity. when sheep were immunized by four 'truncated' larval infections of 4, 7 or 10 days' (d) duration with 10(5) t.c. l3, animals given 4 x 4d infections were susceptible to challenge, whereas sheep given 4 x 7d and 4 x 10d infe ... | 1992 | 1587686 |
| studies of stage-specific immunity against trichostrongylus colubriformis in sheep: immunization with adult parasites. | merino sheep immunized by the adoptive transfer of adult t. colubriformis for 8 weeks were significantly protected against a challenge infection of 20,000 larvae. two additional groups of sheep received a primary infection of 9000 adult worms which were allowed to persist for 14 weeks before one group was drenched. when both groups were challenged 10 days later with 30,000 larvae, serial necropsies of these and naive sheep revealed that worm rejection did not occur until 7-10 days after challeng ... | 1992 | 1587687 |
| a serial study of rejection of trichostrongylus colubriformis by immune sheep. | host responses and the rejection of worms were measured at intervals following challenge of immune and susceptible sheep with t. colubriformis infective larvae. immune sheep rejected most of their larvae within the first day after infection. this early rejection was associated with local appearance of globule leucocytes and increased concentration of t. colubriformis-specific igg1 and igg2 in intestinal mucus. rejection of the remaining worms occurred between 3 and 14 days after infection and wa ... | 1992 | 1587688 |
| induction of tissue eosinophilia by platelet-activating factor in merino sheep. | a study was undertaken on the capacity of platelet-activating factor (paf) to induce eosinophil accumulation in the mammary glands of non-lactating sheep. platelet-activating factor induced dose-dependent accumulation of eosinophils in mammary exudates 24 h after infusion. infection, by intraruminal injection of 20,000 infective trichostrongylus colubriformis larvae, did not modify the responsiveness of outbred sheep to intramammary infusion of paf. mature ewes from high and low responder lines ... | 1992 | 1604802 |
| experimental production of osteoporosis in growing lambs by continuous dosing with trichostrongylus colubriformis larvae. | | 1975 | 1237505 |
| differential stability of the benzimidazole (bz)-tubulin complex in bz-resistant and bz-susceptible isolates of haemonchus contortus and trichostrongylus colubriformis. | the binding of [3h]mebendazole ([3h]mbz) to tubulin from bz-susceptible (bz-s) and bz-resistant (bz-r) isolates of haemonchus contortus and trichostrongylus colubriformis was investigated using charcoal extraction and gel filtration techniques. the amount of [3h]mbz bound at infinite free ligand concentration (bmax) was significantly reduced for the bz-r isolate compared with the bz-s isolate in both species when assayed by charcoal extraction. however, bmax was increased to comparable levels fo ... | 1992 | 1639577 |
| efficacy of p-toluoyl chloride phenylhydrazone against gastrointestinal helminths in ovines. | a new anthelmintic candidate, p-toluoyl chloride phenlylhydrazone, was administered to lambs in a paste formulation. the efficacy of this drug was determined at dose rates of 20, 30, 40, and 50 mg of active ingredient per kilogram of body weight. helminths expelled by these dosages included haemonchus contortus, ostertagia circumcicta, trichostrongylus colubriformis, t. axei, nematodirus filicollis, cooperia curticei, strongyloides papillosus, oesophagostomum columbianum, bunostomum trigoncephal ... | 1976 | 1263040 |
| 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 |
| demonstration of a range of inflammatory mediators released in trichostrongylosis of sheep. | the levels of inflammatory mediators in the intestinal contents of sheep immunized with trichostrongylus colubriformis larvae increased in the first 6 days after challenge. these mediators were histamine, leukotriene c4, 6-keto-prostaglandin f1 alpha (from prostacyclin) and thromboxane b2. leukotriene c4 was released in the greatest quantities. leukotriene b4 was present but its concentration remained unchanged after challenge. the presence of these particular mediators in the intestinal content ... | 1991 | 1680110 |
| the distribution and localization of the stage-specific gp31 antigen from infective ostertagia circumcincta larvae. | the 31,000 mol. wt glycoprotein (gp31) antigen of infective third-stage (l3) ostertagia circumcincta larvae was shown, by surface labelling experiments and immunofluorescent antibody staining of whole larvae and larval sections, to be distributed internally. when transverse sections of l3 o. circumcincta, taken from the anterior pharyngeal region, were further examined by electron microscopy, after immunogold staining with rabbit anti-gp31 antiserum, the gp31 antigen was found to be specifically ... | 1990 | 1690183 |
| gut hypersensitivity reactions in guinea pigs following vaccination or infection with trichostrongylus colubriformis. | a quantitative approach to measuring gut hypersensitivity responses to parasite antigens is described. guinea pigs exposed to infection with trichostrongylus colubriformis, were sensitised to excretory-secretory products and homogenates of third-stage larvae (l3), fourth-stage larvae (l4) and adult worms. the nature of these responses and their modification by pharmacological agents were typical of immediate-type hypersensitivity reactions. gut sensitivity was greatest in the anterior half of th ... | 1990 | 1700768 |
| molecular characterisation of a protective, 11-kda excretory-secretory protein from the parasitic stages of trichostrongylus colubriformis. | an 11-kda protein occurring as a major component of the non-glycosylated fraction of 4th larval stage (l4) and adult trichostrongylus colubriformis excretory-secretory (es) fluid has been found to be highly protective in guinea pigs, an alternate host for t. colubriformis. the protein has been purified, characterised and partly sequenced. with a reverse-complement oligonucleotide based on the carboxy-terminal sequence of the protein, recombinant lambda gt11 clones were detected in an l4 cdna lib ... | 1991 | 1711154 |
| parasitological and immunological responses of genetically resistant merino sheep on pastures contaminated with parasitic nematodes. | one hundred and twenty lambs were grazed continuously from weaning until 9 months of age on 12 plots contaminated with larvae of three nematode species (haemonchus contortus, trichostrongylus colubriformis and ostertagia circumcincta). the lambs were sired by either a genetically resistant ram or susceptible rams (determined by the response of previous progeny to artificial h. contortus infection). half the resistant and half the susceptible lambs were given strategic anthelmintic treatment and ... | 1992 | 1644517 |
| nitrogen transactions along the digestive tract of lambs concurrently infected with trichostrongylus colubriformis and ostertagia circumcincta. | twelve lambs, paired on the basis of live weight, were cannulated in the abomasum, in the proximal jejunum approximately 4 m distal to the pylorus and in the terminal ileum. six were infected with 3000 trichostrongylus colubriformis and 3000 ostertagia circumcincta larvae each day for 18 weeks and the remainder were pair-fed to individual infected lambs. all animals were offered ryegrass (lolium perenne)-white clover (trifolium repens) pasture, cut daily. dry matter (dm) intake, live weight, fae ... | 1991 | 1760444 |
| isolation and degranulation of mucosal mast cells from the small intestine of parasitized sheep. | the isolation of mucosal mast cells and globule leucocytes from the small intestine of sheep immunized with trichostrongylus colubriformis is described. sheep mast cell protease was released from these cells in a dose-dependent fashion after incubation with soluble protein from t. colubriformis larvae. release also occurred with other t. colubriformis antigens whereas non-parasite antigens at comparable protein concentrations evinced only a minimal response. mucosal mast cells prepared from worm ... | 1992 | 1644527 |
| a microlarval development assay for the detection of anthelmintic resistance in sheep nematodes. | a microlarval development test for the detection of anthelmintic resistance in nematodes is described. haemonchus contortus, teladorsagia circumcincta and trichostrongylus colubriformis eggs were cultured to third stage larvae in the presence of earle's balanced salt solution, yeast extract and bacteria in a total volume of 150 microliters. good dose-response data were obtained with thiabendazole, levamisole, pyrantel tartrate and ivermectin allowing the determination of the 50 per cent lethal c ... | 1992 | 1621342 |
| the effect of specific immunization or infection with trichostrongylus colubriformis on production of eosinophil differentiation factors in guinea pigs. | the cultivation of bone marrow was used to quantitate the levels of eosinophil differentiation factors (edf) produced in conditioned medium (cm) by incubation of mesenteric lymph node cells (mlnc) with mitogens or specific antigens from the intestinal nematode parasite, trichostrongylus colubriformis. in liquid cultures with 20 units ml-1 recombinant murine interleukin-5 (il-5), bone marrow cells (bmc) from either normal or infected donors contained less than 5% eosinophils and differentiated to ... | 1991 | 1787028 |
| temperature dependent binding of mebendazole to tubulin in benzimidazole-susceptible and -resistant strains of trichostrongylus colubriformis and caenorhabditis elegans. | the binding of [3h]mebendazole ([3h]mbz) to tubulin in benzimidazole-susceptible (bz-s) and benzimidazole-resistant (bz-r) strains of trichostrongylus colubriformis and caenorhabditis elegans was examined in order to investigate the biochemical changes to tubulin that result in bz resistance in parasitic and free-living nematodes. in both species the extent of [3h]mbz binding to tubulin was significantly reduced in the bz-r strain compared with the bz-s strain. the decrease in [3h]mbz binding in ... | 1991 | 1787034 |
| effect of weaning on antibody responses and nematode parasitism in merino lambs. | lambs weaned at eight weeks old were compared with control lambs which remained with their dams; both groups grazed the same pasture. weaning significantly reduced the growth rate, control lambs being, on average, 6 kg heavier than weaned lambs at 15 weeks old. when contamination of pasture with larval parasites was light, both groups of lambs suffered only modest parasitic infections. when lambs were experimentally infected with 5000 haemonchus contortus and 10,000 trichostrongylus colubriformi ... | 1991 | 1788476 |
| freeze-substitution techniques for preparing nematodes for scanning electron microscopy. | the effect of different substitution times, temperatures and the incorporation of fixatives on the preservation of three species of nematode for scanning electron microscopy by freeze substitution with methanol, followed by critical point drying, is investigated. hammerschmidtiella diesingi adults and trichostrongylus colubriformis infective juveniles were successfully preserved using methanol at 253 k as the substitution medium. preservation deteriorated with long substitution times, suggesting ... | 1991 | 1795382 |
| concurrent infections with the ruminant nematodes haemonchus contortus and trichostrongylus colubriformis in jirds, meriones unguiculatus, and use of this model for anthelmintic studies. | haemonchus contortus- and trichostrongylus colubriformis-infected jirds (meriones unguiculatus) are useful for anthelmintic studies. with concurrent infections of these parasites established in the jird, questions of not only anthelmintic activity, but to some extent spectrum, could be assessed in a single model system. this report outlines a model using immunosuppressed (0.02% hydrocortisone in feed) jirds concurrently infected with h. contortus and t. colubriformis. immunosuppressed jirds were ... | 1991 | 1865271 |