TitleAbstractYear(sorted ascending)
survival and development of larvae of the common nematodes of ruminants after long-term cryopreservation and investigation of different routes of infestation.exsheathed infective larvae (l3) of 16 species of nematodes were tested for infectivity in either sheep or cattle after they had been frozen and stored in 0,09% nacl solution in the gas phase of liquid nitrogen for periods of up to 59 months. a mean of greater than 90% of the l3 of haemonchus contortus, ostertagia circumcincta, trichostrongylus axei, trichostrongylus colubriformis, nematodirus spathiger, oesophagostomum columbianum and chabertia ovina of sheep and haemonchus placei, ostertagia o ...19807465164
influence of plasma a esterase on anthelmintic action of haloxon in sheep.controlled trials were conducted to evaluate the anthelmintic action of haloxon in 2 phenotypes of lambs, 1 having an a esterase in plasma which rapidly hydrolyzes di-(2-chloroethyl)aryl phosphates and the other without this enzyme. a total of 116 lambs, 57 with and 59 without the plasma a esterase, 6 to 9 months old, harboring naturally acquired nematode infections were used in 3 trials. haloxon was administered orally at 20, 25, and 35 mg/kg of body weight. nematodes against which haloxon was ...19807212415
[diffusion of helminth parasites of the digestive system and respiratory system in deer (cervus elaphus) of the la mandria regional park (piedmont)].a study was carried out on the diffusion of helminth parasites of liver, gastrointestinal system and bronchial system in 68 red deer (cervus elaphus) from regional park "la mandria" (piedmont, italy). the following species of nematodes were identified: trichostrongylus axei, spiculopteragia spiculoptera, rinadia mathevossiani, cooperia oncophora, cooperia pectinata, cooperia punctata, cooperia zurnabada, oesophagostomum venulosum, dictyocaulus eckerti, varestrongylus sagittatus. studies on some ...19807312394
efficacy of avermectin b1a for treatment of experimentally induced nematode infections in cattle.two formulations of avermectin b1a, c-076 and mk-933, were examined for anthelmintic activity in two trials, each using 20 calves with experimentally produced nematode infections. in one trial, c-076 was given orally, and in the other trial, mk-933 was given by injection at dosages of 50, 100, and 200 micrograms/kg of body weight. treated calves were held for 7 to 8 days and then, together with nontreated controls, were euthanatized and were examined for nematodes in their gastrointestinal tract ...19806449894
anthelmintic efficiency of ivermectin against naturally acquired bovine gastrointestinal nematodes.ivermectin, one of the new avermectin group of anthelmintics, was more than 99 per cent effective in removing all stages of ostertagia ostertagi including inhibited larvae, and adult trichostrongylus axei when administered to cattle orally at 100 microgram/kg body-weight or subcutaneously at 100 and 200 microgram/kg body-weight. high efficacy (> 98.6 per cent) was also obtained against adults and inhibited larvae of cooperia oncophora at 100 microgram/kg orally or 200 microgram/kg by subcutaneou ...19806893775
efficacy of ivermectin (22,23-dihydroavermectin b1) against gastrointestinal parasites in ponies.the controlled test method was used to evaluate the antiparasitic efficacy of im inoculated 22,23-dihydroavermectin b1 (ivermectin) against gastrointestinal parasites of horses (ponies). parasite infections were naturally acquired in southern louisiana. dose levels of the drug tested were 0.2 mg/kg, 0.3 mg/kg, and 0.5 mg/kg. ivermectin at all dose levels tested had an efficacy greater than 97% (p less than 0.05) against gasterophilus intestinalis larvae, trichostrongylus axei, oxyuris equi larva ...19806894221
anthelmintic activities of ivermectin against gastrointestinal nematodes of cattle.the anthelmintic efficacy of ivermectin, a combined solution of the b1a and b1b fractions of avermectin, was assessed in a controlled trial. twenty-four yearling calves experiencing naturally acquired, clinical gastrointestinal helminthiasis were evenly divided on the basis of weight into two 12-animal groups. the medicated group was given (subcutaneously) ivermectin at the dose rate of 200 microgram/kg of body weight. the control animals were given the vehicle alone, at an equivalent rate. all ...19816895007
anthelmintic efficacy of 22,23-dihydroavermectin b1 against gastrointestinal nematodes in calves.anthelmintic activities of 22,23-dihydroavermectin b1 (comprised to greater than or equal to 95% 22,23-dihydroavermectin b1a and less than or equal to 5% 22,23-dihydroavermectin b1b) against gastrointestinal nematodes in calves were evaluated in 2 controlled experiments. infective larvae of haemonchus contortus, ostertagia ostertagi, trichostrongylus axei, t colubriformis, cooperia oncophora, and c punctate were given to 11-week-old calves and oesophagostomum radiatum had been given 21 days earl ...19816895285
anthelmintic efficacy of ivermectin against immature gastrointestinal pulmonary nematodes of calves.anthelmintic efficacy of ivermectin (greater than or equal to 80% 22,23-dihydroavermectin b1a and less than or equal to 20% 22,23-dihydroavermectin b1b) was evaluated in a controlled experiment against immature nematodes. twenty calves raised to about 8 weeks of age under nematode-free conditions were allocated into 4 groups. infective larvae of haemonchus contortus, ostertagia ostertagi, trichostrongylus axei, t colubriformis, cooperia oncophora, c punctata, oesophagostomum radiatum, and dictyo ...19816896121
anthelmintic treatment of equids: capabilities and limitations. critical tests of nine anthelmintic agents on ponies.a number of good anthelmintic drugs are currently available which eliminate gastrointestinal nematodes of equids with over 90% success. this is shown by comparing results of critical tests conducted with 9 anthelmintic agents on ponies using the following dosages: 19 mg/kg for pyrantel embonate, 10 mg/kg for oxfendazole, 10 mg/kg for mebendazole, 5 mg/kg for albendazole, 40 mg/kg for dichlorvos, 44 mg/kg for thiabendazole, 7.5 mg/kg, for fenbendazole, 20 mg/kg for cambendazole and 7 mg/kg for pa ...19817046611
ivermectin: controlled test of anthelmintic activity in dairy calves with emphasis on dictyocaulus viviparus.twelve dairy calves, naturally infected with lungworms and gastrointestinal parasites, were selected for a controlled test with single doses of ivermectin, administered subcutaneously, at the dose rate of 200 micrograms/kg. specific interest was on efficacy of ivermectin against lungworms (dictyocaulus viviparus), with ancillary interest directed on abomasal parasites. ivermectin was administered to 6 calves, and the vehicle only, to 6 calves. at necropsy, 7 days after treatment, lungworms were ...19816455949
epidemiological observations on stomach worms of horses in morocco.six to nine horses per month (total of 94 in a year) were examined for stomach worms in the settat region of morocco. all the animals were infected by at least one helminth species. habronema muscae occurred in 95.8%, h. majus in 75.6% and trichostrongylus axei in 80.9% of horses. polyparasitism was observed in 93.6% of horses. both for habronema sp. and t. axei the peak worm burden was observed in november and minimum in june. the infection pattern of habronema spp. was directly related to the ...19816456299
anthelmintic activity of paste and drench formulations of oxfendazole in horses.oxfendazole was administered in paste or drench formulations to groups of five horses carrying naturally acquired worm burdens. at a dose rate of 10 mg/kg the efficacy of either formulation appeared similar. one hundred per cent of the adult populations of the following genera was removed: parascaris, oxyuris, strongylus (s edentatus, s vulgaris), triodontophorus and trichostrongylus axei. efficacy against adult small strongyles, adult habronema microstoma and immature oxyuris equi was in the re ...19816461963
a survey of abomasal parasitism in dairy and beef cows in south-west scotland.abomasa were collected from 183 dairy and 186 beef cows in south-west scotland and examined for the presence of nematodes. one hundred and fifty-two of the dairy cows (83 per cent) and 154 of the beef cows (83 per cent) had ostertagia species worm burdens of less than 1000; 4 per cent of both dairy and beef animals had more than 10,000 ostertagia present. the only other nematode detected was trichostrongylus axei and this was present in low numbers in 23 cows (13 dairy and 10 beef). a marked sea ...19817324360
passive transfer of immunity to trichostrongyle species infections in sheep. investigations of specificity and limitations of 'transfer factor' activity with trichostrongylus axei infections.the ability of transfer factor (tf) preparations to transfer resistance to challenge with trichostrongylus axei in sheep and to correct partially the immune immaturity of young lambs was confirmed. non-dialysed tf consistently transferred resistance but dialysed tf frequently failed, perhaps demonstrating a loss of activity during tf preparation procedures. specificity of transfer was demonstrated when t. axei tf transferred resistance to t. axei challenge but haemonchus contortus tf failed to d ...19817342416
studies on haemonchus contortus. iv. the effect of trichostrongylus axei and ostertagia circumcincta on challenge with h. contortus.worm-free merino yearlings were dosed with either a mixture of infective larvae of trichostrongylus axei and ostertagia circumcincta or with o. circumcincta only, and challenged 90-93 days later with infective larvae of haemonchus contortus. neither of these methods protected sheep against challenged and slight protection was afforded sheep predosed with t. axei and o. circumcincta and challenged with a trickle dose of h. contortus.19817345390
efficacy of four anthelmintics in trichostrongylus axei or t. colubriformis infections in the gerbil, meriones unguiculatus. 19817229814
distribution of trichostrongylus axei, t. vitrinus, and t. colubriformis in the stomach and small intestine of the gerbil, meriones unguiculatus. 19817241280
further studies on the efficacy of fenbendazole against inhibited larvae of ostertagia ostertagi.fenbendazole, at low dosage levels, was evaluated for its efficacy against inhibited early fourth stage larvae of ostertagia ostertagi in naturally infected, yearling beef cattle in april. the mean number of inhibited larvae in 10 untreated control cattle was 51,500. at a dosage level of 1 mg per kg (pelleted fenbendazole) per day in feed over five days in 10 cattle, the percentage reduction in comparison to controls was: adults, 85.9 per cent; developing stages, 79.0 per cent; inhibited early f ...19817257120
anthelmintic efficacy of albendazole against inhibited larvae of ostertagia ostertagi.albendazole was evaluated for its efficacy against inhibited early 4th-stage larvae of ostertagia ostertagi for the 3rd consecutive year (april 1979) in naturally infected yearling beef cattle. mean numbers of o ostertagi developmental stages in 10 nontreated controls were: adults, 11,485; developing 4th-stage larvae, 1,370; and early 4th-stage larvae, 51,500. the mean proportion of inhibited early 4th-stage larvae was 76.8%. small numbers of haemonchus sp and trichostrongylus axei were uniforml ...19817258782
seasonal occurence of infective nematode larvae on irrigated pasture grazed by cattle in california.during the period extending from dec 1, 1975, to dec 22, 1976, 3 distinct peaks in the concentration of infective nematode larvae on pasture forage were detected by use of helminth-free tracer calves. two of these peaks, 1 occurring in the spring and 1 in the fall, consisted mainly of ostertagia ostertagi and cooperia sp. it is concluded that these 2 peaks can be anticipated annually and constitute unsafe periods of grazing. the 3rd peak was comprised largely of haemonchus placei and cooperia sp ...19817271041
haloxon: critical tests of antiparasitic activity in equids.critical tests were conducted in 14 naturally infected equids (13 horses and 1 pony) to evaluate the antiparasitic activity of haloxon. single doses were administered by stomach tube to 3 horses and 1 pony (60 mg/kg of body weight), by addition to the feed of 3 horses (60 mg/kg), and intraorally by powder gun to 7 horses (65 mg/kg). haloxon was efficacious (99% to 100%) against infections of parascaris equorum, oxyuris equi (mature and immature), and strongylus vulgaris at both dosage levels. pr ...19817283234
the natural regulation of trichostrongylus spp. populations in young grazing sheep.the dynamics of trichostrongylus axei and intestinal trichostrongylus spp. were studied in grazing lambs over a 2-year period. monthly comparisons were made between worm counts of experimental lambs continuously exposed to infection from 3 to 7 months of age, and tracer lambs which were allowed to graze on the experimental plots for successive 4-week periods. it was found that irrespective of the level of larval intake, experimental lambs were unable to regulate their worm burdens until at least ...19817201183
parasites of chamois in new zealand.abstract sir, - andrews'((2)) checklist of helminth parasites of wild ruminants in new zealand recorded the presence of 10 species of gastrointestinal nematodes in chamois (rupicapra rupicapra rupicapra l.) from "central south island". in october 1978 we examined 28 freshly-shot chamois cadavers from the harper-avoca watershed in the headwaters of the rakaia river. six of the nematode species reported by andrews were found again; viz. ostertagia ostertagi, o. circumcincta, o. trifurcata, nemat ...198122133071
worm burdens of dairy heifers in england and wales.the size and composition of abomasal worm burdens from 143 casualty and cull dairy heifers were estimated. over 60 per cent had totals of less than 10,000, only four exceeded 100,000 and the overall mean was 16,285. ostertagia ostertagi was almost always present and usually formed the major proportion of the total. trichostrongylus axei was recorded in 83 heifers and was the most common species on 17 occasions. the numbers of arrested early fourth stage worms were highest in winter and declined ...19817197843
ivermectin as an antiparasitic agent in horses.ivermectin, described as 22,23-dihydroavermectin b1, was the compound chosen from the avermectin group of compounds for development as an antiparasitic agent in horses. a review of the literature indicates that parenteral administration in horses at 200 microgram/kg body mass is highly effective against the strongyles strongylus vulgaris, strongylus edentatus and triodontophorus spp., and adult and immature cyathostomes, including strains resistant to benzimidazole anthelmintics. other nematodes ...19826750120
worm burdens in cows. ii. an analysis of the population of nematodes in the abomasa of adult dairy cows.over a period of one year, from february 1979-february 1980, the abomasa of four dairy cows were examined each week for the presence of parasitic nematodes. based on the identification of adult male worms, ostertagia ostertagi (94%) and trichostrongylus axei (75%) were the most prevalent species, and haemonchus contortus was absent. total worm burdens varied from zero (one cow) to 100,890. the geometric mean total number was 3011. the geometric mean number of arrested larval stages was 685. of t ...19826890273
gastro-intestinal nematodes in sheep in kashmir.examination at necropsy of the abomasum and intestinal tract of 62 sheep (including both sexes) of karnah breed, aged one to two years over a period of one year was conducted at handwara, situated in the north-west of kashmir valley. the following species of nematodes were found: haemonchus contortus, trichostrongylus axei, trichostrongylus colubriformis, bunostomum trigonocephalum, chabertia ovina, nematodirus spathiger, skrjabinema ovis and trichuris ovis. infections with trichostrongylus axei ...19826891858
studies on haemonchus contortus. vi. attempts to stimulate immunity to abomasal trichostrongylids in merino sheep.two doses of infective larvae of 20 000 trichostrongylus axei, dosed to merino lambs at an interval of 14 days and subsequently challenged with ostertagia circumcincta, caused a significant reduction (p less than 0.01) in the establishment of 5th and adult stages of the latter. t. axei was unable to protect merino sheep against homologous challenge nor was haemonchus contortus a successful vaccine against challenge with the same species. the vaccinated group showed a reduction (p less than 0,025 ...19827122063
evaluation of albendazole in cattle naturally infected with nematodes.albendazole (7.5 mg/kg of body weight) was given to 10 calves naturally infected with gastrointestinal nematodes. ten similar calves served as controls. the compound provided 99% to 100% efficacy in removing haemonchus placei, ostertagia ostertagi, trichostrongylus axei, t colubriformis, nematodirus spathiger, n helvetianus, n filicollis, cooperia oncophora, c punctata, and oesophagostomum radiatum.19827073074
studies on haemonchus contortus. vii. the effect of treatment of trichostrongylus axei prior to challenge with h. contortus.four-month-old worm-free merino lambs were dosed with 20 000 infective larvae of trichostrongylus axei on day 0 and again on day +14. on day +83 they were treated with mebendazole at 15 mg/kg. all lambs in this group and a further group of 11 worm-free merino control lambs were challenged with 50 000 infective larvae of haemonchus contortus dosed from day +90-day +92. at necropsy 27 and 28 days later there was no significant difference between the worm burdens of the 2 groups. t. axei must be pr ...19827122068
helminth and arthropod parasites of springbok, antidorcas marsupialis, in the transvaal and western cape province.the helminth burdens of 17 springbok from 2 localities in the transvaal and of 4 springbok from the western cape province were determined. eight of the animals from the transvaal and the 4 from the cape province were also examined for arthropod parasites. in all, 26 helminth species, 5 species of ixodid ticks and 4 species of lice were recovered from the springbok. of the helminths dictyocaulus magnus, trichostrongylus axei, t. falculatus and agriostomum equidentatum were recovered from animals ...19827122069
anthelmintic efficacy of febantel against gastrointestinal helminths in calves.three dosage levels of febantel were tested for anthelmintic activities in calves under field conditions. a total of 20 feeder calves affected with naturally occurring gastrointestinal parasites were used in the controlled test. the calves were allotted to 4 groups of 5 each on the basis of degree of parasitism, body weight, age, and sex. calves in groups ii through iv were treated with febantel paste formulation at dosage levels of 5, 7.5, and 10 mg/kg of body weight; calves in group i were use ...19827165174
the trichostrongyloid parasites of sheep in south australia and their regional distribution.the species of trichostrongyloid nematodes present in 376 sheep from different agricultural regions of the state of south australia were determined. parasites encountered in the abomasum were teladorsagia circumcincta, t. trifurcata, t. davtiani, camelostrongylus mentulatus, haemonchus contortus and trichostrongylus axei. t. circumcincta was the species most commonly encountered, but c. mentulatus was widespread in arid areas. h. contortus was present in a small number of sheep only, mainly in s ...19827168719
helminth and arthropod parasites of blesbok, damaliscus dorcas phillipsi, and of bontebok, damaliscus dorcas dorcas.the helminth burdens of 8 blesbok shot in the north-eastern orange free state, 8 from the eastern cape province, 28 from the eastern transvaal and 3 from the central transvaal were determined. in addition, the arthropod burdens of 11 of these animals were ascertained. twenty-one nematode species, 2 cestode species, 6 ixodid ticks, 2 lice and the larvae of 5 oestrid flies were recovered. three of the nematode species, 2 of the oestrid flies and 4 of the tick species had apparently not previously ...19827177591
studies on haemonchus contortus. viii. attempts to protect suckling lambs against infestation with h. contortus.a group of 12 merino lambs, 3,5 months of age, which were still suckling, were each dosed with 40 000 infective larvae of trichostrongylus axei on day 0. from day +62-day 64 each of these lambs and those of a 2nd group of 11 controls were dosed with 30 000 infective larvae of haemonchus contortus, and all the lambs of both groups were killed on day +90. attempts to use t. axei to protect them against subsequent challenge with h. contortus were unsuccessful.19827177593
the effect of predosing calves with trichostrongylus axei on subsequent challenge with haemonchus placei.twelve calves were dosed with 40 000 and a further 12 with 80 000 infective larvae of trichostrongylus axei respectively. these 2 groups and a control group were subsequently dosed with 50 000 infective larvae of haemonchus placei. predosing with t. axei had no effect on the establishment of h. placei. it is postulated that the numbers of t. axei worms present were below the 'threshold' value necessary to protect the calves against challenge with h. placei.19827177596
anthelmintic efficacy of ivermectin given intramuscularly in horses.the anthelmintic activity of ivermectin was evaluated in 18 female horses with naturally acquired parasitic infections. horses were treated once (im) with vehicle only (n = 6), 200 microgram/kg of body weight (n = 6), and 300 microgram/kg (n = 6). efficacy of both dosages of ivermectin was greater than 99% against gasterophilus spp, 100% against trichostrongylus axei, habronema muscae, h majus, and draschia megastoma, 98% to 99% against adult cyathostomes, 86% to 97% against 4th-stage cyathostom ...19826896407
ivermectin: activity against larval strongylus vulgaris and adult trichostrongylus axei in experimental infections in ponies.activity of ivermectin, administered im at the dosage rate of 200 micrograms/kg of body weight, was evaluated in controlled tests against migrating larvae of strongylus vulgaris and adult trichostrongylus axei in experimental infections in 6 ponies raised worm-free. ponies were given 2,190 or 2,400 infective 3rd-stage larvae of s vulgaris at 7 days before treatment and 22,000 or 22,750 infective 3rd-stage larvae of t axei at 42 or 45 days before treatment. three ponies were given ivermectin plus ...19826896612
efficacy of injectable and oral paste formulations of ivermectin against gastrointestinal parasites in ponies.a controlled test was used in ponies to compare the antiparasitic efficacy of ivermectin (22,23-dihydro-avermectin b1) in an injectable micelle solution administered im with the efficacy of the same drug in an oral paste formulation. parasite infections were naturally acquired in southern louisiana. the drug was tested in both formulations at a dosage level of 0.2 mg/kg of body weight. ivermectin in both formulations tested had an efficacy greater than 98% against gasterophilus intestinalis and ...19826896613
[human infestations by trichostrongylus axei, t. capricola and t. vitrinus: 1st report in italy].the authors refer the first report in italy of human infection with trichostrongylus axei and trichostrongylus vitrinus. further studies are in progress on 68 male specimens identified as belonging to trichostrongylus capricola group.19826926930
efficacy of ivermectin against naturally acquired and experimentally induced nematode infections in sheep.the activity of ivermectin against common nematode parasites of sheep was examined in 2 experiments. in the 1st experiment, 14 sheep with naturally acquired infections were assigned to 2 groups of 7 sheep each. sheep in 1 group were treated with 200 micrograms of ivermectin/kg of body weight and the remainder served as nontreated controls. in the 2nd experiment, 15 sheep with experimentally supplemented infections (including a benzimidazole-resistant strain of haemonchus contortus) were assigned ...19827041712
[first sign in italy of nematodirus roscidus, apteragia quadrispiculata and ostertagia drozdzi, found in dama dama].the authors refer the first report in italy of nematodirus roscidus railliet, 1911, apteragia quadrispiculata jansen, 1958 and ostertagia drozdzi jancev, 1977 from dama dama. in fallow deer they found also: trichostrongylus axei, trichostrongylus colubriformis, trichostrongylus vitrinus, spiculopteragia asymmetrica, skrjabinagia arctica, oesophagostomum venulosum, trichuris ovis. trichostrongylus axei, trichostrongylus colubriformis, trichostrongylus vitrinus and skrjabinagia arctica were not fo ...19836543932
further tests of activity of levamisole on ostertagia ostertagi in dairy calves with notes on overwinter survival of gastrointestinal helminths on pasture.two controlled tests were conducted in 1981 and 1982 in dairy calves on the university of kentucky research farm to determine activity of the bolus formulation of levamisole given at the dose rate of 8 mg/kg against naturally occurring infections of ostertagia ostertagi. removal efficacies of mature o ostertagi were 98% in the 1981 test (3 treated and 3 nontreated calves) and 94% in the 1982 test (7 treated and 8 nontreated calves). against immature ostertagia spp, removal efficacies were 100% a ...19836625330
some helminth and arthropod parasites of the grey duiker, sylvicapra grimmia.sixteen grey duikers were culled on the farm riekert 's laager in the central transvaal at irregular intervals from may 1979-march 1981. one trematode species, 3 cestode species and 16 nematode species were recovered from these animals. of these the following are new helminth records for this antelope: cooperia hungi , cooperia neitzi , cooperia pectinata , trichostrongylus axei, trichostrongylus colubriformis, trichostrongylus falculatus , trichostrongylus instabilis , impalaia tuberculata , ne ...19836676685
alternate grazing of horses and sheep as control for gastro-intestinal helminthiasis in horses.gastro-intestinal helminth infections of a group of three yearling mare shetland ponies, which were set-stocked on a small pasture from february until september, were compared with those of a similar group of ponies, which grazed a similar pasture from february to july and subsequently was removed to a pasture which had been grazed by sheep from april to july. in addition both groups were treated with cambendazole when the latter group was removed to the sheep pasture. pasture larval counts and ...19836686382
parasites in kentucky thoroughbreds at necropsy: emphasis on stomach worms and tapeworms.a total of 363 thoroughbreds (62 males, 292 females, and 9 geldings), 1 to 26 years of age, were examined at necropsy for internal parasites for about a 12-month period from february 1981 through february 1982. emphasis was on examining the stomach for nematodes and the small intestine and cecum for tapeworms. parasites recovered from the stomach and infection rates were: habronema spp--immature (24%), h muscae--adult (38%), draschia megastoma--immature (13%), d megastoma--adult (62%), and trich ...19836869991
studies on haemonchus contortus. xii. effect of trichostrongylus axei in dorper lambs on natural pasture lightly infested with h. contortus.weaned dorper lambs on natural pasture were predosed with 40 000 infective larvae (l3) of trichostrongylus axei, irradiated (0,3 kgy) l3 of t. axei or closantel at 10 mg/kg either in september or november 1978 and were compared with merino yearlings predosed with 40 000 l3 of t. axei in november 1977. the following summer (december-march) only 178,6 mm of rain fell and very few h. contortus were present on pastures. artificial challenge with 20 000 l3 of haemonchus contortus with the local strai ...19846462635
studies on haemonchus contortus. xi. the effect of a bovine strain of trichostrongylus axei in merinos on natural pastures heavily infested with h. contortus.sheep grazed on natural pastures heavily infested with infective larvae of haemonchus contortus. sixty-eight weaned merinos were divided into 6 groups on day 0 (23 november 1977), and on day +14 (7 december) 79 merinos were divided into 7 groups. there were 2 groups of undosed controls and other groups were either dosed with infective larvae of trichostrongylus axei (bovine strain) only on days 0 and +14, or in combination with h. contortus, or with subsequent doses of h. contortus, 28 days late ...19846462634
studies on haemonchus contortus. ix. the effect of trichostrongylus axei in merinos on natural pasture.four groups of 6-7-month-old merino lambs were each dosed with 40 000 infective larvae of trichostrongylus axei on 2 november 1976 and subsequently exposed to challenge with haemonchus contortus on natural grazing at the university of pretoria's experimental farm in the eastern suburbs of pretoria. one of these groups and one group of controls were killed every 8 weeks from the end of december 1976-june 1977. predosing with t. axei was greater than 50% effective against 5th stage and adult h. co ...19846462631
studies on haemonchus contortus. x. the effect of trichostrongylus axei in merinos on artificial pastures.a recently established eragrostis curvula pasture 1,1 ha in size at hennops river in the transvaal highveld was contaminated from 6 october 1976 until 20 may 1977 by 30 weaned merinos, each infested with 7 000 infective larvae of h. contortus. on 2 november 1976 3 groups of weaned merinos and again on 10 january 1977 a further group of merinos were infested with 40 000 infective larvae of trichostrongylus axei. from 19 november a single group of sheep, predosed with t. axei, and a control group ...19846462632
leukokinesis in bovine ostertagiasis: stimulation of leukocyte migration by ostertagia.a blind-well chemotaxis chamber method was used to indicate migration stimulation of bovine neutrophil and eosinophil polymorphonuclear leukocytes and macrophages as related to ostertagiasis. live exsheathed ostertagia ostertagi 3rd-stage larvae (l3) and soluble l3 antigen (sla), prepared by freeze thawing and sonic disruption of l3, enhanced cellular migration for eosinophils, but not for neutrophils and macrophages. products of lymphocytes cultured with sla for 3 to 6 hours were also examined, ...19846742569
efficacy of ivermectin in oral paste formulation against immature gastrointestinal and pulmonary nematodes in cattle.the anthelmintic efficacy of ivermectin in oral paste formulation was evaluated against the 4th-stage larvae of 8 gastrointestinal nematodes and the common lung-worm in 14 experimentally inoculated calves. two groups consisting of 7 calves each were formed by restricted randomization on body weight. the infective larvae were given orally to the animals on a staggered schedule so that the parasites were in the 4th larval stage when the animals were treated. one group was given vehicle paste, and ...19846547278
efficacy of fenbendazole against inhibited larvae of ostertagia ostertagi in yearling cattle.efficacy of fenbendazole, at doses of 7.5 and 10.0 mg/kg of body weight, against inhibited early 4th-stage larvae of ostertagia ostertagi and other nematodes of the abomasum and intestinal tract, was investigated in naturally infected yearling heifers in late may 1982. in louisiana, this is near the end of the period (march to may) in which maximal numbers of inhibition-prone larvae are acquired. the mean numbers of o ostertagi in 10 untreated control cattle were: adults, 4,880; developing 4th-s ...19846497097
an epidemiological study of trichostrongylidiasis in dairy cattle grazing irrigated pastures.trichostrongylid burdens in 1 to 2-year-old dairy heifers were estimated after they grazed with a dairy herd for up to 12 months. ostertagia ostertagi, trichostrongylus axei and cooperia oncophora represented 79.5, 12.7 and 7.8% respectively of all trichostrongylids recovered. the largest burden was 97,000 trichostrongyles with less than 20,000 being the typical burden. clinical disease was not observed. the strain of o. ostertagi present was capable of inhibition and was not necessarily control ...19846497788
stocking rate effects on the worm burdens of angora goats and merino sheep.worm egg counts of yearling angora or merino wethers grazing in mixed flocks at either 4/ha or 8/ha were observed over a 5 month period. based on faecal egg counts infection levels in the sheep increased for the first 3 months and then decreased as the animals developed resistance. egg counts in the goats did not decrease during the experiment. post mortem worm counts indicated that there was a significant host species--stocking rate interaction on worm burdens of haemonchus contortus adults and ...19846517775
seasonal changes in the abomasal nematodes of naturally infected ewes in moulay-bouazza (morocco).the nematode populations of 93 abomasa of ewes from middle-atlas (morocco) were studied over a period of 3 years. the main species present were ostertagia circumcincta, marshallagia marshalli, trichostrongylus axei and t. vitrinus; less frequent species were o. ostertagi and o. trifurcata. two peaks of infection were recorded, 1 at the end of winter or the beginning of spring (february--march), and another in autumn (september). the first population peak consisted mostly of o. circumcincta and t ...19846541394
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, ...19846377988
seasonal occurrence of infective nematode larvae in california high sierra pastures grazed by cattle.worm-free holstein calves were used to assess the seasonal variation in numbers of nematode infective larvae on herbage at 2 commercial cow-calf ranches in the sierra nevada mountains. both ranches used herefords as their basic breed. one ranch near sattley, california, is at an elevation of approximately 1,500 m above sea level, whereas the study area on the 2nd ranch near susanville is at an elevation of approximately 1,250 m above sea level. worm-free tracer calves were allowed to graze for a ...198424049905
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 ...19853838393
anthelmintic activity of ivermectin against immature gastrointestinal nematodes of sheep.twenty-four lambs of mixed breeding with mixed experimental infections of haemonchus contortus, ostertagia circumcincta, trichostrongylus axei, and t colubriformis were allotted to 4 groups. one group (control) was given the vehicle propylene glycol, and the others were given 100, 200, or 300 micrograms of ivermectin/kg of body weight by mouth. twelve days after treatment, the sheep were necropsied. the compound was greater than 99% effective against immature stages of 4 nematode species at all ...19853840965
prevalence of some internal parasites recovered at necropsy of thoroughbreds born in 1982 in kentucky.a total of 89 thoroughbreds, 14 to 333 days old (born in 1982), were examined at necropsy for certain internal parasites during a 1-year-period, mar 1, 1982, to feb 28, 1983. the eyes of 73 of the horses and the cranial mesenteric arteries of 71 were examined. specific interest was on prevalence of parasites according to month of the year and age of the horses at necropsy. parasites recovered (first month-last month infected horse found) were as follows: thelazia lacrymalis (eyes) immature and m ...19853994134
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 ...19854037502
first record of trichostrongylus axei infection of man in the caribbean region. 19854082271
peripheral blood white cell responses during concurrent copper deficiency and gastro-intestinal nematodiasis in sheep.sheep experimentally depleted of copper (cu) and infected with trichostrongylus axei and trichostrongylus colubriformis were studied for changes in white blood cell (wbc) populations, anti-parasite antibody responses and in vitro proliferative response to phytohaemagglutinin (pha), lipopolysaccharide (lps) and trichostrongylus spp. antigens. increases in circulating total wbc, lymphocyte, monocyte and neutrophil leucocyte numbers had a bimodal distribution which was related to the different deve ...19854062699
effects of concurrent copper deficiency and gastro-intestinal nematodiasis on circulating copper and protein levels, liver copper and bodyweight in sheep.sheep were rendered hypocupraemic using parenteral ammonium tetrathiomolybdate (atm). fifteen thousand third stage larvae of trichostrongylus axei and t. colubriformis in the ratio 1:1 were administered three times per week for six weeks, starting four weeks after cessation of atm treatment. the changes in liver and plasma copper (cu), caeruloplasmin activity, serum proteins, faecal nematode egg counts and total nematode counts were measured in the sheep for 10 weeks after infection. decreases i ...19863962164
the comparative efficacy of oxfendazole administered as bolus and suspension to naturally infected sheep in a flock of 20 ewes naturally infected with those parasites of sheep most common in greece, and kept indoors during the whole trial, oxfendazole at the dose rate of approximately 2.9 and 2.8 mg/kg body-weight was tested as a 4 g bolus containing 112 mg active ingredient and a 2.265% suspension. the evaluation of its efficacy was based on the necropsy findings which were also supported by faecal egg counts. no differences in efficacy were noticed between the two formulations of the drug. both b ...19863745877
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 ...19863946069
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, ...19863946888
control of strongylosis in horses by alternate grazing of horses and sheep and some other aspects of the epidemiology of strongylidae infections.alternate grazing of horses and sheep as a control measure for gastrointestinal helminthiasis was studied in three grazing experiments in 1981, 1982 and 1983. each year a group of three mare yearling shetland ponies, which were kept on a small pasture from spring to autumn, were compared with a similar group which grazed a similar or the same pasture until july and were subsequently removed to a similar pasture which had been grazed by sheep from april to july. in addition both groups were treat ...19863962151
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 ...19863962170
abomasal parasitism in dairy cows in belgium.over a period of one year, from march 1984 to april 1985, the abomasa of 157 dairy cows in east flanders (belgium) were collected and examined for the presence of nematodes. faeces and blood were also collected from the animals. no worms were recovered from 18 cows (11.5%), 118 cows (75%) had a low to moderate worm burden (10-10,000) and 21 cows (13.5%) a high worm burden (greater than 10,000). the geometric mean total number was 2171. ostertagia ostertagi and trichostrongylus axei were the main ...19863564332
[microecological characterization of parasitic nematoda present in goats of arid zones of venezuela].goats from the venezuelan northern arid zones were found infested by the following nematodes: haemonchus contortus, trichostrongylus axei, t. colubriformis, cooperia curticei, oesophagostomum columbianum, skrjabinema ovis y trichuris globulosa. the shannon-weaver index of diversity values oscillated between 0.045 and 1.73 bits (means = 1.16 +/- 0.24 bits). the maximum value of montly diversity ranged from 1 to 2.80 bits (means = 2.49 +/- 0.28 bits) and the equitability ranged from 0.045 to 0.67 ...19863587000
the helminth parasites of various artiodactylids from some south african nature reserves.the helminth species composition and helminth burdens of 4 grey duikers, 12 bushbuck, 2 nyala, 2 giraffe, a steenbok, an oribi, a waterbuck and a tsessebe from the kruger national park (knp); of a steenbok and a greater kudu from the farm riekerts laager, transvaal; of a single blue duiker from the tsitsikama forest national park, and of a blue wildebeest, a red hartebeest, a gemsbok and 2 springbok from the kalahari gemsbok national park (kgnp) were collected, counted and identified. new parasi ...19863725333
activity of ivermectin against natural infections by abomasal nematodes in lambs in controlled tests: evaluation of equine and bovine injectable formulations administered intraorally.the efficacy of 2 injectable formulations of ivermectin, administered intraorally at the dosage of 200 micrograms/kg of body weight, was evaluated against naturally occurring infections by abomasal nematodes in lambs in 2 controlled tests. one test (a) included 17 lambs treated with the equine formulation and 16 nontreated lambs. for the other test (b), 14 lambs were treated with the bovine formulation, and 12 were nontreated. in controlled test a, only mature nematodes were recovered, and remov ...19863755309
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 ...19863788027
epidemiology and control of equine strongylosis at newmarket.seasonal rises in mean faecal egg output were observed in grazing ponies in spring (578 eggs per gram) and in summer (930 epg) on 30 april and 2 september, respectively, in untreated ponies. pasture infectivity reached a peak of 18,486 third stage larvae (l3)/kg on 17 september, two weeks after peak egg counts, coincidental with abundant september rainfall (103.0 mm). differentiation of infective larvae from pasture showed the cyathostomes (small strongyles) to be predominant, but trichostrongyl ...19863803357
serum protein changes in ponies on different parasite control programmes.serum protein responses were examined in 52 ponies divided into five groups and subjected to various control strategies that resulted in pasture infectivity ranging from 706 to 18,486 infective third stage, cyathostome and trichostrongylus axei larvae per kilogram of herbage (l3/kg) by 17 september 1984. major protein changes occurred only in young ponies (groups 4 and 5) and were observed before exposure to maximum numbers of pasture larvae (group 4; 10,210 l3/kg, group 5: 10,042 l3/kg) on 17 s ...19863803358
serum pepsinogen concentrations of ponies naturally infected with trichostrongylus axei. 19863803365
oxfendazole resistance in trichostrongylus axei in cattle in australia. 19863811178
the occurrence and abundance of helminth parasites of the mountain hare lepus timidus (l.) and the wild rabbit oryctolagus cuniculus (l.) in aberdeenshire, scotland.mountain hares were collected each month between april 1984 and march 1985 and their intestines examined for helminths. 26 rabbits were also collected between july and december 1984 and examined for gastro-intestinal helminths. three nematode and two cestode species were found in the hares while only two nematode and one cestode species were found in the rabbits. trichostrongylus retortaeformis was recorded from 88% of the 193 hares and 92% of the rabbits while comparable figures for passalurus ...19863734402
parasites in sheep grazing on kikuyu (pennisetum clandestinum) pastures in the winter rainfall region.regular worm counts were done post-mortem on sheep that had grazed on kikuyu pastures at the elsenburg research station near stellenbosch, a winter rainfall region. major species were trichostrongylus colubriformis, trichostrongylus axei, while ostertagia circumcincta was usually present in large numbers. minor species were haemonchus contortus, nematodirus spathiger, dictyocaulus filaria, oesophagostomum venulosum, trichuris spp., chabertia ovina and larvae of the arthropod oestrus ovis. muelle ...19873587925
efficacy of fenbendazole-medicated feed blocks against gastrointestinal nematode infections in 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 ...19873605803
parasites of south african wildlife. i. helminths of bushbuck, tragelaphus scriptus, and grey duiker, sylvicapra grimmia, from the weza state forest, natal.thirteen bushbuck, tragelaphus scriptus, and 13 grey duikers, sylvicapra grimmia, were culled in the weza state forest, natal, from may 1983-may 1984. the maximum number of worms recovered from a single bushbuck was 393. of the total number of worms recovered from all the bushbuck, paracooperia devossi were the most numerous, followed by ostertagia harrisi, a cooperia sp. and haemonchus vegliai. p. devossi and o. harrisi were more numerous during winter and the cooperia sp. more numerous during ...19873627728
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 ...19873670895
monthly and seasonal fluctuations in abomasal nematode worm burden of naturally infected cattle in austria.from october 1980 until september 1981, 191 abomasa of naturally infected cattle were obtained from the slaughter-houses of mürzhofen and graz in the province of styria, and of wiener neustadt in the province of lower austria and examined to study the monthly and seasonal occurrence of hypobiosis in ostertagia ostertagi and trichostrongylus axei. infections in pastured animals (cows, steers and heifers) were compared with those in stabled animals (bulls fed on green forage and silage). except fo ...19873564352
prevalence of internal parasites in horses in critical tests of activity of parasiticides over a 28-year period (1956-1983) in kentucky.the prevalence and number of naturally acquired gastrointestinal parasites were compiled for horses used in critical tests of activity of parasiticides over a 28-year period (1956-1983). data are presented as follows: n = number of horses examined; % = mean prevalence; number in parentheses after % = aggregate mean number of parasites in infected horses. parasites found were: bots (n = 513) - gasterophilus intestinalis, 2nd instar, 61%(58); 3rd instar, 94%(168); g. nasalis, 2nd instar, 36%(28); ...19873564356
common internal parasites found in the stomach, large intestine, and cranial mesenteric artery of thoroughbreds in kentucky at necropsy (1985 to 1986).a total of 278 thoroughbreds (less than 1 to 31 years old) were examined at necropsy (july 9, 1985, to feb 2, 1986) in kentucky for various internal parasites. examination was not made of all the horses for each of the parasites. specific parasites recovered from the stomach of foals (n = 30) and yearlings and older horses (n = 96) and percentage (in parentheses) of each age category infected, respectively, were as follows: gasterophilus intestinalis 2nd instar (53% and 32%) and 3rd instar (37% ...19872950814
efficacy of ivermectin against the abomasal nematode mecistocirrus digitatus in naturally infected zebu calves.anthelmintic efficacy of ivermectin against mecistocirrus digitatus was evaluated in 10 naturally infected zebu calves. group 1 (n = 5) was not treated, and group 2 (n = 5) was treated sc with 200 micrograms of ivermectin/kg of body weight. calves were euthanatized 14 or 15 days after treatment. there was 100% overall reduction of m digitatus in treated calves, which was significant (p = 0.0079) compared with reduction in controls. cooperia punctata, haemonchus similis, and trichostrongylus axei ...19873434907
parasites of the stomach in donkeys of the highveld of zimbabwe.fourteen donkeys from a communal area of the zimbabwean highveld were examined for stomach parasites during july and november of 1986 and january and april of 1987. all 14 animals were infected. habronema muscae occurred in 12, draschia megastoma in 11, h. majus in 9, trichostrongylus axei in 9, gasterophilus intestinalis in 14 and g. nasalis in 1 donkey. the lowest level of infection was in january for the helminths and in april for gasterophilus larvae. the peak burdens of parasites were in ju ...19882975414
efficacy of febantel against abomasal nematodes and lungworms in cattle.the efficacy of febantel at a dosage of 5 mg/kg (45.5% paste formulation) against inhibited early 4th-stage larvae (el4) of ostertagia ostertagi, other nematodes of the abomasum, and dictyocaulus viviparus was investigated in 4- to 6-month-old holstein calves that grazed on pasture heavily contaminated with parasites from february 24 to april 1, 1986 (36 days). in louisiana, this is the first month of a 3-month period in which increasing numbers of inhibition-prone o ostertagi larvae are acquire ...19882977070
prophylactic efficacy of an ivermectin sustained-release bolus against challenge exposure with gastrointestinal and pulmonary nematode infective larvae in calves.twelve holstein calves were used to determine the prophylactic efficacy of ivermectin against challenge exposure with gastrointestinal and pulmonary nematodes. two groups of 6 calves (mean body weight, 205 kg) each were formed by restricted randomization according to body weight. group-1 calves served as nonmedicated controls. each calf of group 2 was orally given one prototype sustained-release bolus designed to deliver ivermectin at a continuous daily dose of 8 mg. third-stage nematode infecti ...19883189987
high concentration of serum gastrin immunoreactivity and abomasal mucosal hyperplasia in calves infected with ostertagia ostertagi and/or trichostrongylus axei.parasite-free, 4-month-old-calves were inoculated with ostertagia ostertagi and/or trichostrongylus axei, followed 6 weeks later by inoculation with increasing doses of o ostertagi for 8 weeks in the 2 groups (n = 4) of calves that had been given o ostertagi. gastrin immunoreactivity concentration in serum was measured before and after infection and was correlated with changes in mucosal thickness. gastrin immunoreactivity concentration in preinoculation control sera ranged from 95.2 to 287.1 pg ...19883239847
prophylactic efficacy of sustained-release ivermectin against induced nematode infestations in cattle.the efficacy of sustained-release ivermectin was evaluated against challenge infestations of gastro-intestinal nematodes in a laboratory study involving 12 treated and 12 untreated control cattle. a weighted, orally administered osmotically activated device designed to lodge in the rumeno-reticulum and to deliver ivermectin at a dosage rate of approximately 8 mg/day for a 120-day period, was administered to treated cattle. animals were challenged with infective larvae of bunostomum phlebotomum a ...19883361567
seasonal prevalence of gastrointestinal nematodes of beef calves grazed on irrigated pastures in the lower sacramento valley of california.two worm-free calves were allowed to graze on irrigated pasture with a naturally infected herd for each of 34 one-month periods from november 1979 to august 1982. after each grazing period, the calves were transferred to a cement-floored pen for 3 weeks and then were euthanatized and necropsied. ostertagia ostertagi and cooperia oncophora were the most prevalent species of nematodes recovered. adults and larvae of ostertagia spp and cooperia spp were most numerous in winter and spring and least ...19883377319
effect of strategic anthelmintic treatment and pasture management on productivity and control of nematode parasites in weaner-yearling beef cattle.three groups of 17 beef calves were used to evaluate effects of strategic anthelmintic treatment on safe (group 1) and contaminated (group 2) pasture in comparison with minimal treatment at weaning and contaminated pasture (group 3). the investigation extended from weaning in november 1982 to the following august. results of faecal egg counts, herbage larval counts, plasma pepsinogen and tracer calf worm counts in autumn and spring indicated minimal levels of infection on safe pastures provided ...19883222550
persistent anthelmintic activity of topically administered ivermectin in cattle.the persistent anthelmintic effect of ivermectin as a topical treatment at 500 microg/kg was evaluated against induced infections of ostertagia ostertagi, trichostrongylus axei and dictyocaulus vivparus in calves. the results showed a highly significant (p<0.001) anthelmintic activity for at least 14 days against o. ostertagi and t.axei (>99 per cent efficacies) and for at least 28 days (98 per cent efficacy) against d. viviparus.198916031549
the relation between the natural worm burden of steers and the faecal egg count differentiated to species.the relation between the faecal egg count and the worm burden was investigated in 104 steers of three breeds, 9-24 months of age, which were subjected to natural infection with nematode larvae from pasture at the national cattle breeding station near rockhampton in central queensland. the worm species found were cooperia spp., haemonchus placei, trichostrongylus axei, oesophagostomum radiatum and small numbers of bunostumum phlebotumum. the faecal egg count was found to be a reliable measure of ...19892728323
[the helminth fauna of the gastrointestinal tract of young cattle in northwest germany].ten unmedicated animals of a controlled anthelmintic trial were used to analyse the present gastrointestinal helminth fauna of young cattle from the northwest of germany. this survey done in august revealed ostertagia ostertagi to represent the most prevalent and abundant species followed by cooperia oncophora and nematodirus helvetianus. o. lyrata, o. leptospicularis, c. zurnabada, c. punctata, trichostrongylus axei, haemonchus contortus, bunostomum phlebotomum, capillaria bovis and trichuris d ...19892598802
controlled test and clinical evaluation of dienbendazole against naturally acquired gastrointestinal parasites in ponies.a controlled test was performed to titrate the anthelmintic dosage of dienbendazole in 24 mixed-breed ponies naturally infected with strongylus vulgaris, s edentatus, and small strongyle species, as determined by parasitic egg and larval counts in feces. comparison of results of treatment was made among 3 dienbendazole dosages--2.5, 5, and 10 mg/kg of body weight--and a gum (excipient) mixture given by nasogastric intubation. all ponies were euthanatized and necropsied at 7 or 8 days after treat ...19892619127
Displaying items 101 - 200 of 395