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1.
Borgsteede FH Tibben J Cornelissen JB Agneessens J Gaasenbeek CP 《Veterinary parasitology》2000,89(4):287-296
Abomasa, blood samples and faecal samples for examination of nematode infections were collected from 125 dairy cows during the period November 1997-October 1998. Of these, 12 had no grazing history and were, therefore, excluded from this study. From the remaining 113, 88.5% had nematode eggs in the faeces. Larval identification of the positive cultures showed that Ostertagia spp. larvae were most frequent (97%), followed by Trichostrongylus spp. (29%), Oesophagostomum spp. (23%), Cooperia punctata (20%), Cooperia oncophora (4%), Haemonchus contortus (2%) and Bunostomum phlebotomum (1%). The geometric mean EPG was 2.4. Two cows excreted larvae of Dictyocaulus viviparus (0.1 and 0.6 LPG resp.). Worms were found in the abomasa of 108 cows (96%). In all these abomasa Ostertagia spp. was present (100%). Trichostrongylus axei was found in 47 abomasa (43.5%) and two cows (2%) were infected with Capillaria bovis. The geometric mean of the total abomasal worm counts was 1743 and of Ostertagia spp. alone 1615. Almost all male worms were Ostertagia ostertagi, only occasionally Skrjabinagia lyrata10,000) total worm burden.Ostertagia specific antibodies were highest in late summer and autumn and lowest in spring and early summer. The same pattern, although not so pronounced, was observed for the serum pepsinogen values. No clear seasonal pattern was found for the Cooperia specific antibodies. Antibodies against D. viviparus were detected in seven cows (6%). 相似文献
2.
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 species involved, with the former accounting for 90% of all trichostrongyles recovered. For both worms a seasonal pattern was evident, with the highest worm counts in December-January. Between December and February greater than 97% of the Ostertagia spp. worm burden were EL4. For all animals the average pepsinogen level was 1391 +/- 494 mU tyrosine with no statistically significant relationship between pepsinogen levels and the total number of gastric nematodes. Only 45% of the faeces samples were positive for strongylid eggs with a mean of 43 eggs per gram. The percentage generic composition of L3 larvae collected from faeces was 62% Ostertagia, 18% Trichostrongylus, 6% Cooperia, 4% Oesophagostomum and 0.2% Bunostomum. 相似文献
3.
O M el-Azazy 《Veterinary parasitology》1990,37(1):55-60
A total of 96 abomasa from sheep and goats at the Zagazig abattoir, Sharkia Province, Egypt, were examined, during the four climatic seasons from April 1986 to March 1987, for the presence of adult and larval nematodes. Adults of Trichostrongylus axei were most numerous followed by adult Haemonchus contortus. Adult Ostertagia sp. and Parabronema skrjabini were less prevalent. There was no significant difference between sheep and goats in infection rates, but worm burdens of the nematodes other than Ostertagia sp. were significantly higher (P less than 0.05) in sheep than in goats. The animals were uniformly infected with these parasites throughout the year as there were no significant differences in the incidence or intensity of infections between the four seasons. The numbers of larvae recovered from the wall of the abomasa were small in relation to the total adult worm population throughout the year with a slight increase during the summer. Hypobiosis, therefore, seems not to be important in the life cycle of abomasal nematodes of sheep and goats in Sharkia Province, Egypt. 相似文献
4.
The number and species of helminth parasites from three gemsbok (Oryx gazella) were recorded, and their faecal nematode egg counts and the level of pasture contamination determined. Six nematode genera were recovered and four species identified, of which Trichostrongylus rugatus was the most prevalent. Other nematode species recovered were Cooperia sp., Agriostomum sp., Haemonchus contortus, Nematodirus spathiger and Ostertagia ostertagi. None of the worms were present in all animals studied, and no new host associations were found. Cysticerci were recovered from the mesenteries of one gemsbok and a further two unidentifiable helminths were recovered from the abomasum and the kidney fat layer of another antelope. 相似文献
5.
Multiple species of nematodes resistant to ivermectin and a benzimidazole-levamisole combination on a sheep farm in New Zealand 总被引：1，自引：0，他引：1
AIM: To confirm the presence of multiple anthelmintic resistance on a sheep farm in New Zealand. METHODS: Three groups of 10 weaned Romney-cross lambs were treated either with an oral dose of ivermectin (0.2 mg/kg), or a benzimidazole/levamisole (BZ/LEV) combination (4.75 albendazole and 7.5 mg/kg levamisole), or were left untreated. Ten days later, animals were necropsied, and adult worms recovered and identified from the abomasa and small intestines. Pre- and post-treatment faecal nematode egg counts (FEC) were recorded, and larval cultures were performed. RESULTS: In a faecal egg count reduction test (FECRT), adjusted to reflect pre- and post-treatment larval culture results, ivermectin resistance was detected in Teladorsagia (Ostertagia), Trichostrongylus and Haemonchus spp, while BZ/LEV combination- resistant Teladorsagia and Trichostrongylus spp were also present. Adult worm counts confirmed these results, and identified the species involved as Teladorsagia circumcincta, Trichostrongylus colubriformis and H. contortus. CONCLUSION: Multiple, multi-generic anthelmintic resistance was confirmed on a sheep property in New Zealand. This included the first confirmed case of ivermectin resistance in T. colubriformis from sheep in New Zealand. 相似文献
6.
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 removals were 98% to 100% for Haemonchus contortus, Ostertagia circumcincta male, O trifurcata male, Ostertagia spp female, and Trichostrongylus axei. For controlled test B, removals were 99% to 100% for Haemonchus spp (immature), H contortus (mature), Ostertagia spp (immature), O circumcincta male (mature), O trifurcata male (mature), Ostertagia spp female (mature), Trichostrongylus spp (immature), and T axei (mature). Toxicosis was not evident in treated lambs. 相似文献
7.
J Boomker I G Horak J R Flamand 《The Onderstepoort journal of veterinary research》1991,58(4):275-280
The helminths of 77 nyala, Tragelaphus angasii, from 4 game reserves in Natal, were collected, counted and identified. Ten nematode species and 4 nematode genera, a trematode species and paramphistomes, and 2 cestode genera were recovered from the antelope. Of these, a Cooperia rotundispiculum race, Gaigeria pachyscelis, a Gongylonema sp., Haemonchus vegliai, Impalaia tuberculata, an Oesophagostomum sp., a Setaria sp., Trichostrongylus deflexus, Trichostrongylus falculatus, the larval stage of a Taenia sp., a Thysaniezia sp. and Schistosoma mattheei are new parasite records for this host. Individual nematode helminth burdens varied from 3 to 13 493 and the total mean nematode burden was 700. The mean burdens of nyala from Mkuzi were the largest and those from animals from the Umfolozi Game Reserve and the False Bay Park the smallest. Ostertagia harrisi was the most prevalent nematode, and it was also the most numerous in nyala from Umfolozi, Mkuzi and False Bay. A race of Cooperia rotundispiculum was the most numerous in nyala from Ndumu. No clear-cut trends in the seasonal abundance could be discerned for any of the worm species recovered in this study. 相似文献
8.
J C Williams K S Marbury C S Eddi E R Willis D G Luther 《American journal of veterinary research》1988,49(12):2085-2089
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 acquired, and infection risk with D viviparus may remain high. Three of 4 calves that died of lungworm infection during the pasture-exposure period were necropsied. Large numbers of abomasal nematodes, including inhibited O ostertagi larvae, and large numbers of D viviparus were recovered. Twenty-five calves were randomly allotted by equal distribution of body weight to 2 groups and treated on April 4: placebo-treated calves (n = 13) and febantel-treated calves (n = 12). Equal numbers of treated and control calves were killed at 6 and 7 days, respectively, after treatment. Mean numbers of O ostertagi in control cattle were: adults, 4,931; developing 4th-stage larvae (DL4), 1,119; and inhibited EL4, 3,410. Ostertagia lyrata, Trichostrongylus axei, Haemonchus sp, and D viviparus were well distributed in nearly all control calves. Percentage reduction of O ostertagi in treated calves, when compared with controls, was: adults, 83.6%; DL4, 57.8%; and inhibited EL4, 34.8%. Percentage reductions of other species were: O lyrata, 92.6%; T axei adults, 99.3% and 4th-stage larvae (L4), 100%; Haemonchus sp adults, 66.7%, and L4, 64%; D viviparus adults 90.6%, and immature forms, 97.1%.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Type II ostertagiosis was found at necropsy in 9 American bison (Bison bison) from 3 farms in New York. Clinical signs included severe diarrhea, emaciation, unthrifty coats, anemia, and weakness. In severely affected animals, the macroscopic abomasal changes consisted of irregular thickening and edema of the mucosa, resulting in a pebbly or morocco-leather appearance. Microscopically, many gastric pits and glands were dilated, lined by hyperplastic epithelium, and contained nematode sections or debris. Parasites recovered included Ostertagia ostertagi, Trichostrongylus axei, Trichostrongylus lerouxi, Cooperia oncophora, Haemonchus contortus, Nematodirus helvetianus, Trichuris discolor, Setaria labiato-papillosa, Dictyocaulus viviparus, Hypoderma lineatum, and Sarcocystis sp. Nodules in the small and large intestine were attributed to Oesophagostomum sp. Trichostrongylus lerouxi, Trichuris discolor, and Nematodirus helvetianus are reported from bison for the first time. 相似文献
10.
B B Fakae 《Veterinary parasitology》1990,36(1-2):123-130
A survey was conducted in the Nigerian derived savanna (from August 1987 to July 1988) on the seasonal fluctuations in the composition of Haemonchus contortus burden of naturally infected West African Dwarf sheep and goats. During this period 117 abomasa collected from locally slaughtered animals were processed. Male, female as well as immature worms were enumerated. The incidence of Haemonchus infection was high (77.8-100%) with no definite seasonal distinction. There was however, a clear seasonal trend in the worm burden of animals; higher burdens were evident during the rainy rather than the dry season. There was no significant hypobiosis; Haemonchus contortus survived in the host during the unfavourable dry season (November to March) as adults. 相似文献
11.
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 for 10 bulls fed on silage all animals were parasitized. The results indicate that in Austria inhibited early fourth stage larvae of Ostertagia accumulate during the winter. Pastured animals showed a higher intensity of infection than stabled animals. Cows less than 3 and greater than 5 years of age had higher worm counts than those between these ages. There was a simultaneous accumulation of third stage larvae and adult worms of Trichostrongylus axei in autumn in steers and heifers. In bulls fed on green forage a higher adult worm burden was seen in winter. No significant correlation existed between the number of worm nodules in the abomasal mucosa and the various developmental stages of the worms. The count of in-utero immature eggs was higher in stabled than in pastured animals. No significant correlation between the number of in-utero eggs and that of female worms was noticeable. Numbers of mature Ostertagia eggs rose in spring, while in fall and winter the immature eggs predominated. An increase in the uterine egg count was observed in Trichostrongylus in autumn. Statistical analyses of our data show that the most decisive factor influencing the numbers of inhibited and adult Ostertagia as well as in-utero eggs is the system of animal management. 相似文献
12.
T M Craig 《Journal of the American Veterinary Medical Association》1979,174(8):844-847
Sentinel calves were placed in pastures for 1 month in two environmentally dissimilar areas of the Texas Gulf Coast to determine the seasonal transmission of various gastrointestinal nematodes. Transmission was determined for Cooperia spp, Haemonchus placei, Ostertagia ostertagi, and Trichostrongylus axei. Large numbers of Cooperia spp were acquired from May through November, with the peak of transmission occurring in July and August. Haemonchus placei was encountered on both field sites but was transmitted in large numbers only at one site, during August. Ostertagia ostertagi was acquired primarily from November through May, with the peak of transmission occurring in January and February. January through March was the period when the greatest numbers of Ostertagia larvae undergoing arrested development were acquired. Trichostrongylus axei was abundance in December and January at one field site. In general, trends of transmission were the same in both areas, indicating that weather conditions were most important than vegetation type in larval transmission. 相似文献
13.
J Boomker W H Du Plessis E A Boomker 《The Onderstepoort journal of veterinary research》1983,50(4):233-241
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 , Nematodirus sp. and Paramphistomum sp. In addition, 6 species of ixodid ticks were collected. These, in order of abundance, were Amblyomma hebraeum (55,9%), Rhipicephalus appendiculatus (36,6%), Rhipicephalus evertsi evertsi (5,1%), Boophilus decoloratus (2,3%), Boophilus microplus (0,05%) and Haemaphysalis sp. (0,05%). Only 60 (2,8%) of the 2 118 ticks that were collected were adults. Of the 3 species of lice that were recovered, Linognathus zumpti zumpti was most abundant (58,9%), but, out of a total of 1 498 collected, 1 496 occurred on 1 animal only. Linognathus breviceps constituted 29,5% and Damalinia lerouxi 11,6% of the total. A total of 277 specimens of the hippoboscid fly Lipoptena paradoxa were collected from 12 of the 16 animals examined. Trends in the seasonal fluctuation of Haemonchus, Trichostrongylus, Impalaia , Lipoptena and the immature stages of Amblyomma and R. appendiculatus are graphically illustrated. 相似文献
14.
J C Williams 《Veterinary parasitology》1991,40(1-2):59-71
An experiment was conducted to compare the anthelmintic efficacy of albendazole (ABZ), levamisole (LEV) and fenbendazole (FBZ) against inhibited early fourth stage larvae (EL4) of Ostertagia ostertagi during April in Louisiana. Forty cross-bred beef heifers (average weight 165 kg) were acquired during winter and grazed on pastures contaminated with O. ostertagi and other nematodes until early April. The cattle were weighed and randomly allotted into four groups of ten animals on 6 April and treatments were administered on 7 April. Experimental groupings were: Group 1, non-treated controls; Group 2, ABZ by oral drench at 10 mg kg-1; Group 3, LEV by topical, pour-on administration to back midline at 10 mg kg-1; Group 4, FBZ by oral drench at 10 mg kg-1. Equal numbers of cattle from each group were slaughtered daily between 10 and 13 days after treatment. Mean numbers of O. ostertagi developmental stages present in untreated controls were: adults, 13,714; developing L4 (DL4), 6487; inhibited EL4, 21,719. The mean percentage of inhibited EL4 was 51.8. Smaller numbers of Haemonchus placei, Trichostrongylus axei and Cooperia spp. were recovered uniformly in control cattle. Percentage reduction values for the three compounds against O. ostertagi adults, DL4 and EL4, respectively, were: ABZ, 99.0, 95.3, 84.9; LEV, 1.0, 21.8, 32.1; FBZ, 99.2, 97.2, 97.5. Differences between ABZ and LEV EL4 counts were not significant, but in all other cases worm counts in ABZ and FBZ-treated cattle were significantly lower (P less than or equal to 0.05) than in LEV-treated and control cattle. Both ABZ and FBZ were 98-100% effective against Haemonchus adults and L4, T. axei adults, and Cooperia spp. adults and L4. LEV was 100% effective against Haemonchus adults and L4, 85.6% against T. axei, and 94.6% and 89.59% effective against Cooperia spp. adults and L4, respectively. 相似文献
15.
On the basis of worm counts in naturally infected Angora-X goats, albendazole at either 3.8 mg/kg repeated after 24 hours or as a single dose at 7.6 mg/kg, was >99% effective in removing adult Ostertagia and Trichostrongylus spp. Small numbers of adult Haemonchus contortus, Cooperia sp. and Chabertia ovina were present in control but not treated animals. The single dose of 7.6 mg/kg removed >99% of adult Oesophagostomum venulosum whereas the repeated dose of 3.8 mg/kg removed only 96%. 相似文献
16.
The effectiveness of anthelmintics was evaluated in four herds of captive ruminants, wapiti (Cervus elaphus), Armenian red sheep (Ovis orientalis), giraffe (Giraffa camelopardalis), and pronghorn (Antilocapra americana), by the use of fecal egg reduction tests (FERTs) and a commercial larval development assay (LDA) designed to evaluate susceptibility or resistance of nematodes to anthelmintics. Haemonchus sp. was the predominant nematode in the red sheep, giraffe, and pronghorn herds, whereas Ostertagia sp. and Trichostrongylus sp. were predominant in the wapiti. The LDA data indicated susceptibility by the worms to benzimidazoles except in the red sheep flock, which showed a high level of resistance. High levels of resistance to levamisole were seen in the worm populations from the wapiti and red sheep, moderate resistance in the pronghorn herd, and susceptibility in the giraffe herd. Worms were susceptible in all four herds to a combination of benzimidazole/levamisole. There was suspected avermectin resistance by Trichostrongylus sp. in the wapiti herd and by Haemonchus sp. in the giraffe. The FERTs agreed with the LDA in showing the Haemonchus in the giraffe was susceptible to fenbendazole and had suspected resistance to ivermectin, whereas Haemonchus in the red sheep and pronghorn were susceptible to ivermectin. There was correlation between the tests evaluating anthelmintics. The LDA is useful as a screening test in the selection of an anthelmintic for use in grazing ruminants, but the effectiveness of a drug in a host species may depend as much on the dose used, and the method of administration, as it does on the parasite's sensitivity to the anthelmintic. 相似文献
17.
A study was made to compare the numbers of infective ovine nematode parasite larvae on an open pastured block and an adjacent block forested with Pinus radiata at 200 stems per hectare. Each block consisted of two paddocks which had similar nematode parasite egg contamination. Infective larvae of six genera were recovered over a 12 month period viz., Trichostrongylus spp., Ostertagia spp., Cooperia spp., Nematodirus spp., Chabertia/Oesophagostomum spp. and Haemonchus sp. A significantly higher recovery of Trichostrongylus spp. (p<0.01) and Ostertagia spp. (p<0.05) from the pine forested block was probably due to the more favourable climatic environment under the pines. The lower mean body weights of sheep grazing the pine block was considered to be due to the greater exposure to infective larvae and marginal under-nutrition. 相似文献
18.
19.
Infective larvae of selected batched of the following nematode species from sheep and cattle were examined for survival and infectivity (by injection into either the abomasum, the duodenum, or the jugular vein) after having been stored in liquid nitrogen for 103-136 months: Haemonchus contortus, Haemonchus placei, Ostertagia circumcincta, Ostertagia ostertagi, Marshallagia marshalli, Cooperia spp., Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus falculatus, Nematodirus spathiger, Nematodirus helvetianus, Oesophagostomum columbianum, Oesophagostomum radiatum, Chabertia ovina and Dictyocaulus filaria. Excluding D. filaria, a mean of 97.7% of the ovine and 96.0% of the bovine nematode larvae were alive when thawed. Compared with previous investigations in this series, little or no reduction occurred with time in either the survival or the viability of the nematodes from cattle, or in the survival of those from sheep. In contrast, the larvae developed poorly in sheep, possibly owing to parenteral treatment of the animals with ivermectin at a dosage of 0.4 mg kg-1, either 6 or 8 days before they were infected. 相似文献