Displaying publications 1 - 20 of 33 in total

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  1. Anthelmintic resistance in sheep and goat farms on Peninsular Malaysia
    Chandrawathani P, Adnan M, Waller PJ
    Vet Parasitol, 1999 May;82(4):305-10.
    PMID: 10384906
    The faecal egg count reduction test (FECRT) was conducted on 39 sheep farms and 9 goat farms located in Peninsular Malaysia. The anthelmintic groups used in these tests were the benzimidazoles, levamisole, the benzimidazole/levamisole combination, macrocyclic lactones and closantel. Results indicated that the prevalence of resistance to the benzimidazole group was high, with approximately 50% of the sheep farms and 75% of the goat farms having resistant nematode parasite populations present. Resistance to levamisole, closantel and ivermectin was also detected. Differentiation of the infective larvae derived from faecal cultures indicated that by far the most predominant parasite species was Haemonchus contortus.
    Matched MeSH terms: Haemonchus/drug effects*
  2. Sympatric species distribution, genetic diversity and population structure of Haemonchus isolates from domestic ruminants in Pakistan
    Hussain T, Periasamy K, Nadeem A, Babar ME, Pichler R, Diallo A
    Vet Parasitol, 2014 Dec 15;206(3-4):188-99.
    PMID: 25468018
    Haemonchus species are major gastro-intestinal parasites affecting ruminants across the world. The present study aimed to assess the sympatric species distribution, genetic diversity, population structure and frequency of β-tubulin isotype 1 alleles associated with benzimidazole resistance. Internal transcribed spacer 2 (ITS2) sequences revealed three sympatric species of Haemonchus, H. contortus, H. placei and H. longistipes with 12 distinct genotypes circulating among ruminant hosts in Pakistan. High genetic variability was observed in Pakistani Haemonchus isolates at nicotine amide dehydrogenase subunit 4 (ND4) and cytochrome oxidase subunit 1 (COI) gene loci. Intra-population diversity parameters were higher in H. contortus isolates than H. placei. Phylogenetic analysis of ND4 and COI sequences did not reveal clustering of haplotypes originating from a particular host indicating high rate of gene flow among Haemonchus parasites infecting sheep, goat and cattle in Pakistan. ND4 and COI haplotypes from Pakistan were compared to sequences of Haemonchus isolates from 11 countries to elucidate the population structure. Multidimensional scaling (MDS) plot of pairwise FST derived from 531 ND4 haplotypes revealed clustering together of H. contortus from Pakistan, China, Malaysia and Italy while the isolates from Yemen and United States were found to be genetically distinct. With respect to H. placei, isolates from Pakistan were found to be genetically differentiated from isolates of other countries. The tests for selective neutrality revealed negative D statistics and did not reveal significant deviations in Pakistani Haemonchus populations while significant deviation (P < 0.05) was observed in Brazilian and Chinese H. contortus populations. Median Joining (MJ) network of ND4 haplotypes revealed Yemenese H. contortus being closer to H. placei cluster. β-tubulin isotype 1 genotyping revealed 7.86% frequency of Y allele associated with benzimidazole resistance at F200Y locus in Pakistani Haemonchus isolates.
    Matched MeSH terms: Haemonchus/genetics*
  3. Multiple and multigeneric anthelmintic resistance on a sheep farm in Malaysia
    Sivaraj S, Dorny P, Vercruysse J, Pandey VS
    Vet Parasitol, 1994 Oct;55(1-2):159-65.
    PMID: 7886917
    The anthelmintic efficacy of benzimidazoles, levamisole, closantel, ivermectin and moxidectin was evaluated on an institutional farm in Malaysia using faecal egg count reduction tests, controlled slaughter trials and an in vitro egg hatch assay. The results of this study indicated simultaneous resistance of Haemonchus contortus against benzimidazoles and ivermectin and of Trichostrongylus colubriformis against benzimidazoles and levaminsole on the same farm. Moxidectin was effective against the ivermectin resistant H. contortus.
    Matched MeSH terms: Haemonchus/drug effects
  4. Anthelmintic resistance in Haemonchus contortus from sheep in Malaysia
    Pandey VS, Sivaraj S
    Vet Parasitol, 1994 May;53(1-2):67-74.
    PMID: 8091619
    Albendazole, oxfendazole, fenbendazole, levamisole, closantel, ivermectin and febantel were administered to sheep on four farms and their efficacy assessed by faecal egg count reduction test. High level of resistance of Haemonchus contortus was found to benzimidazoles (albendazole, oxfendazole, fenbendazole) on all farms and to febantel on the one farm where it was tested. No resistance to closantel and levamisole was observed. Resistance to ivermectin was absent on the three farms examined under this study, but has been reported on the fourth farm in earlier work. It is concluded that anthelmintic resistance to benzimidazoles and the probenzimidazole, febantel, is a serious and widespread problem in H. contortus in sheep in Malaysia.
    Matched MeSH terms: Haemonchus/drug effects*
  5. Kinetics of IgA and eosinophils following a low-dose, predominantly Haemonchus contortus infection of Boer goats
    Hayyan BN, Sharma RSK, Raimy N, Nisha M, Hussain K, Busin VM, et al.
    Parasite Immunol., 2020 06;42(6):e12707.
    PMID: 32118305 DOI: 10.1111/pim.12707
    AIMS: Most breeds of goat are more susceptible to nematode infection than sheep, and this appears to be a consequence of less effective immune responses. Several papers have considered the effectiveness of eosinophils and immunoglobulin A (IgA) in goats but differences in the induction of responses have not been studied in the same detail. The aim of this study was to look at the induction of eosinophil and IgA responses in Boer goats reared indoors under intensive conditions.

    METHODS AND RESULTS: The goats were experimentally infected with a low dose of 2400 Haemonchus contortus, Trichostrongylus spp. and Oesophagostomum spp. at a 6:1:1 ratio. Faecal egg counts (FEC), packed cell volume (PCV), IgA activity against third-stage larvae and peripheral eosinophilia were measured twice a week for eight weeks. The infection generated an IgA response but did not significantly increase peripheral eosinophilia in the 25 infected kids compared with the 4 control animals. FEC was not associated with IgA activity or eosinophilia.

    CONCLUSION: A detailed analysis of IgA and eosinophil responses to deliberate nematode infection in Boer goats showed that there was an increase in nematode-specific IgA activity but no detectable eosinophil response. In addition, there was no association between increased IgA activity or eosinophilia with egg counts and worm burdens. These suggest that IgA and eosinophils do not act to control nematode infection in goats.

    Matched MeSH terms: Haemonchus/immunology*
  6. Fulltext Co-infection of Haemonchus contortus and Trichostrongylus spp. among livestock in Malaysia as revealed by amplification and sequencing of the internal transcribed spacer II DNA region
    Tan TK, Panchadcharam C, Low VL, Lee SC, Ngui R, Sharma RS, et al.
    BMC Vet Res, 2014;10:38.
    PMID: 24502557 DOI: 10.1186/1746-6148-10-38
    Haemonchus contortus and Trichostrongylus spp. are reported to be the most prevalent and highly pathogenic parasites in livestock, particularly in small ruminants. However, the routine conventional tool used in Malaysia could not differentiate the species accurately and therefore limiting the understanding of the co-infections between these two genera among livestock in Malaysia. This study is the first attempt to identify the strongylids of veterinary importance in Malaysia (i.e., H. contortus and Trichostrongylus spp.) by amplification and sequencing of the Internal Transcribed Spacer II DNA region.
    Matched MeSH terms: Haemonchus/isolation & purification*
  7. Sensitivity of two in vitro assays for evaluating plant activity against the infective stage of Haemonchus contortus strains
    Al-Rofaai A, Rahman WA, Abdulghani M
    Parasitol Res, 2013 Feb;112(2):893-8.
    PMID: 22961237 DOI: 10.1007/s00436-012-3113-5
    The sensitivity of larval paralysis assay (LPA) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide-formazan (MTT-formazan) assay was compared to evaluate the anthelmintic activity of plant extracts. In this study, the methanolic extract of Azadirachta indica (neem) was evaluated for its activity against the infective-stage larvae (L(3)) of susceptible and resistant Haemonchus contortus strains using the two aforementioned assays. In both in vitro assays, the same serial concentrations of the extract were used, and the median lethal concentrations were determined to compare the sensitivity of both assays. The results revealed a significant difference (P < 0.05) in the sensitivity of the LPA and the MTT-formazan assay. The MTT-formazan assay is more feasible for practical applications because it measured the L(3) mortality more accurately than LPA. This study may help find a suitable assay for investigating the anthelmintic activity of plant extracts against trichostrongylid nematodes.
    Matched MeSH terms: Haemonchus/drug effects*
  8. Resistance to benzimidazole anthelmintics by Haemonchus contortus in goats in peninsular Malaysia
    Rahman WA
    Vet Parasitol, 1994 Oct;55(1-2):155-7.
    PMID: 7886916
    A previous study had suggested that local strains of goat trichostrongyles, comprising largely Haemonchus contortus, might have developed resistance to benzimidazole anthelmintics. A trial involving 18 goats was conducted to confirm this. There was a significant (P < 0.01) reduction in worm burdens in goats given levamisole, but this was not so for those animals given albendazole, fenbendazole, oxfendazole and mebendazole (P > 0.05).
    Matched MeSH terms: Haemonchus/drug effects*
  9. Survey for drug-resistant trichostrongyle nematodes in ten commercial goat farms in west Malaysia
    Rahman WA
    Trop Anim Health Prod, 1994 Nov;26(4):235-8.
    PMID: 7900221
    The prevalence of drug-resistant parasites in goats in West Malaysia has rarely been reported. Ten commercial goat farms were surveyed for resistance to anthelminthics by measuring the reduction in faecal egg counts (FECs) after treatment with levamisole, pyrantel pamoate and fenbendazole. Resistance to fenbendazole was seen in most farms; there was no evidence of resistance to levamisole but some resistance to pyrantel pamoate was detected on one farm. The significance of the findings are discussed.
    Matched MeSH terms: Haemonchus/drug effects
  10. The kinetic properties of the glutamate dehydrogenase of Teladorsagia circumcincta and their significance for the lifestyle of the parasite
    Muhamad N, Simcock DC, Pedley KC, Simpson HV, Brown S
    Comp Biochem Physiol B Biochem Mol Biol, 2011 Jun;159(2):71-7.
    PMID: 21296180 DOI: 10.1016/j.cbpb.2011.01.008
    Like other nematodes, both L(3) and adult Teladosagia circumcincta secrete or excrete NH(3)/NH(4)(+), but the reactions involved in the production are unclear. Glutamate dehydrogenase is a significant source NH(3)/NH(4)(+) in some species, but previous reports indicate that the enzyme is absent from L(3)Haemonchus contortus. We show that glutamate dehydrogenase was active in both L(3) and adult T. circumcincta. The apparent K(m)s of the L(3) enzyme differed from those of the adult enzyme, the most significant of these being the increase in the K(m) for NH(4)(+) from 18mM in L(3) to 49mM in adults. The apparent V(max) of the oxidative deamination reaction was greater than that of the reductive reaction in L(3), but this was reversed in adults. The activity of the oxidative reaction of the L(3) enzyme was not affected by adenine nucleotides, but that of the reductive reaction was stimulated significantly by either ADP or ATP. The L(3) enzyme was more active with NAD(+) than it was with NADP(+), although the activities supported by NADH and NADPH were similar at saturating concentrations. While the activity of the oxidative reaction was sufficient to account for the NH(3)/NH(4)(+) efflux we have previously reported, the reductive amination reaction was likely to be more active.
    Matched MeSH terms: Haemonchus/enzymology
  11. Total anthelmintic failure to control nematode parasites of small ruminants on government breeding farms in Sabah, East Malaysia
    Chandrawathani P, Yusoff N, Wan LC, Ham A, Waller PJ
    Vet Res Commun, 2004 Aug;28(6):479-89.
    PMID: 15509022
    Government-owned small-ruminant breeding farms in Malaysia provide the source of sheep and goats to smallholder farmers in the country. In the eastern Malaysian state of Sabah, high-level stock losses have been recorded on these farms for several years, frequently accompanied by clinical signs indicating pathogenic levels of infections with the nematode parasite Haemonchus contortus. This suggests that their dependence on chemotherapy to control parasite infections had failed. Accordingly, tests for anthelmintic efficacy using the faecal egg count reduction test (FECRT) on the range of drugs used to control nematode parasites were carried out on the five government small-ruminant breeding farms in Sabah. These tests showed a total failure of the benzimidazole, imidothiazole, macrocyclic lactone and salicylanilide groups of anthelmintics to control H. contortus infections of sheep and goats on all farms. Drastic changes in animal management need to be made in an attempt to deal with this situation, for which suggestions are made.
    Matched MeSH terms: Haemonchus/drug effects
  12. Fulltext Genetic diversity of Haemonchus contortus isolated from sympatric wild blue sheep (Pseudois nayaur) and sheep in Helan Mountains, China
    Shen DD, Wang JF, Zhang DY, Peng ZW, Yang TY, Wang ZD, et al.
    Parasit Vectors, 2017 Sep 19;10(1):437.
    PMID: 28927469 DOI: 10.1186/s13071-017-2377-0
    BACKGROUND: Haemonchus contortus is known among parasitic nematodes as one of the major veterinary pathogens of small ruminants and results in great economic losses worldwide. Human activities, such as the sympatric grazing of wild with domestic animals, may place susceptible wildlife hosts at risk of increased prevalence and infection intensity with this common small ruminant parasite. Studies on phylogenetic factors of H. contortus should assist in defining the amount of the impact of anthropogenic factors on the extent of sharing of agents such as this nematode between domestic animals and wildlife.

    METHODS: H. contortus specimens (n = 57) were isolated from wild blue sheep (Pseudois nayaur) inhabiting Helan Mountains (HM), China and additional H. contortus specimens (n = 20) were isolated from domestic sheep that were grazed near the natural habitat of the blue sheep. Complete ITS2 (second internal transcribed spacer) sequences and partial sequences of the nad4 (nicotinamide dehydrogenase subunit 4 gene) gene were amplified to determine the sequence variations and population genetic diversities between these two populations. Also, 142 nad4 haplotype sequences of H. contortus from seven other geographical regions of China were retrieved from database to further examine the H. contortus population structure.

    RESULTS: Sequence analysis revealed 10 genotypes (ITS2) and 73 haplotypes (nad4) among the 77 specimens, with nucleotide diversities of 0.007 and 0.021, respectively, similar to previous studies in other countries, such as Pakistan, Malaysia and Yemen. Phylogenetic analyses (BI, MP, NJ) of nad4 sequences showed that there were no noticeable boundaries among H. contortus populations from different geographical origin and population genetic analyses revealed that most of the variation (94.21%) occurred within H. contortus populations. All phylogenetic analyses indicated that there was little genetic differentiation but a high degree of gene flow among the H. contortus populations among wild blue sheep and domestic ruminants in China.

    CONCLUSIONS: The current work is the first genetic characterization of H. contortus isolated from wild blue sheep in the Helan Mountains region. The results revealed a low genetic differentiation and high degree of gene flow between the H. contortus populations from sympatric wild blue sheep and domestic sheep, indicating regular cross-infection between the sympatrically reared ruminants.

    Matched MeSH terms: Haemonchus/genetics*
  13. Seasonal variations in the populations of infective larvae on pasture and the numbers of nematode eggs in the faeces of farmed goats
    Rahman WA, Collins GH
    J Helminthol, 1990 Sep;64(3):263-70.
    PMID: 2230037
    The levels of nematode egg production in goats and the availability of infective larvae (L3) on pasture were investigated on a dairy unit in New South Wales, Australia. The output of eggs by adult goats was always above 300 epg. The profile of the graph of larval availability in herbage paralleled those for temperature and rainfall, suggesting that larval peaks occurred when the temperature and availability of moisture were optimal. The dominant genus was Trichostrongylus, followed by Haemonchus, then Ostertagia. A larger proportion of Haemonchus larvae in the cultures of faeces were collected during the summer months.
    Matched MeSH terms: Haemonchus/growth & development
  14. Fulltext The prevalence of parasitic infestation of small ruminant farms in perak, malaysia
    Zainalabidin FA, Raimy N, Yaacob MH, Musbah A, Bathmanaban P, Ismail EA, et al.
    Trop Life Sci Res, 2015 Apr;26(1):1-8.
    PMID: 26019746 MyJurnal
    Helminthiasis due to strongyles such as Haemonchus contortus, coccidiosis caused by Eimeria sp. and blood parasite diseases such as theileriosis by Theileria sp. have been reported to cause severe morbidity and mortality annually in small ruminants in Malaysia. The aims of this study were to investigate the prevalence of helminthiasis, coccidiosis and theileriosis and to determine the packed cell volume (PCV) value of small ruminants in Perak, Malaysia. Blood and faecal samples were obtained from a total of 175 animals from 7 small ruminant farms in Kampar, Larut Matang and Selama, Kuala Kangsar and Manjung districts in Perak; the samples were examined for parasitic infestations from April to July 2011. The results of this study show that H. contortus was found in 152 (86.86%) animals, Eimeria sp. was found in 162 (92.57%) animals and the blood protozoa Theileria sp. was found in 25 (14.30%) animals. The PCV values of all of these animals were recorded between 7% and 44%. A total of 42 (24%) animals were anaemic, with a PCV of less than 21%. Continuous monitoring of small ruminant farms will provide important information for assisting farmers with managing the spread of parasitic infections and maintaining the productivity of animals.
    Matched MeSH terms: Haemonchus
  15. Nematode control failure due to anthelmintic resistance in a sheep farm in Malaysia: First identification of the F200Y mutation in the isotype 1 β-tubulin gene
    Khadijah S, Wahaf ANS, Syahmi MI, Tan TK, Low VL, Azrul LM, et al.
    Trop Biomed, 2018 Dec 01;35(4):999-1006.
    PMID: 33601847
    This paper reports total nematode anthelmintic resistance towards albendazole, fenbendazole, levamisole and ivermectin in a commercial sheep farm located in Terengganu, Malaysia. Faecal Egg Count Reduction Test (FECRT) was conducted on 25 sheep, where five sheep in each group were treated with the respective four anthelmintics based on live bodyweight. The balance of five sheep placed in the control group were not treated with any anthelmintics. At day 13 post-treatment, faecal egg count was conducted and nematode worm egg count reduction percentage was calculated to determine the resistance status towards the respective anthelmintics tested. Results showed that nematodes were resistant to all the anthelmintics tested, namely albendazole, fenbendazole, levamisole and ivermectin with reduction percentage of 87%, 46%, 94% and 68%, respectively. Subsequently, the third stage larvae of Haemonchus contortus and Trichostrongylus colubriformis recovered from post-treatment faecal cultures were subjected to allele-specific polymerase chain reaction (AS-PCR) assay to determine the presence of the benzimidazole resistance gene. This study reports the occurrence of the classical F200Y mutation in the isotype 1 βtubulin gene, for the first time in Malaysia.
    Matched MeSH terms: Haemonchus
  16. Genetic variation of Haemonchus contortus (Trichostrongylidae) in sheep and goats from Malaysia and Yemen
    Gharamah AA, Azizah MN, Rahman WA
    Vet Parasitol, 2012 Sep 10;188(3-4):268-76.
    PMID: 22538095 DOI: 10.1016/j.vetpar.2012.04.003
    The large stomach worm, Haemonchus contortus, commonly known as "the barber's pole worm", is a blood-sucking nematode found in the abomasa of sheep and goats. This work is the first documentation on the ND4 sequences of H. contortus from sheep and goats in Malaysia and Yemen and the results provide a preliminary insight on the genetic differences of H. contortus found in the two countries. In general, this study showed a high degree of diversity and low population structure of this species within the same country in comparison with higher genetic structuring at a wider geographical scale. The results also showed that the majority of genetic variance was within H. contortus populations. The Malaysian sheep and goat populations investigated appeared to share the same isolate of H. contortus while different isolates may be found in Yemen which must be taken into account in the design of an effective control strategy. Analysis of the internal transcribed spacer-2 (ITS-2) confirmed that all samples investigated in this study belonged to H. contortus. However presence of other Haemonchus species parasitizing these two hosts can only be confirmed by further detailed studies.
    Matched MeSH terms: Haemonchus/classification; Haemonchus/genetics*
  17. Epidemiology of gastro-intestinal nematodes of sheep in wet tropical conditions in Malaysia
    Cheah TS, Rajamanickam C
    Trop Anim Health Prod, 1997 Aug;29(3):165-73.
    PMID: 9316233
    A study on the seasonal variations in the population structure of Haemonchus contortus and Trichostronglyus colubriformis was conducted for a period of 12 months in a typical large scale sheep farm on improved pasture in Peninsular Malaysia which has a wet tropical climate. Successive groups of helminth-free tracer lambs were grazed for 4 weeks together with naturally infected sheep and were necropised for worm counts 2 weeks after their removal from the pasture. The monthly populations of H. contortus fluctuated slightly except in May and August during which more worms were found in the tracer animals. The numbers of T. colubriformis were comparatively high from October to December 1992 and again in March 1993, low during April and June 1992. Small numbers of hypobiotic larvae of H. contortus were detected in the tracer animals. Development and survival of infective larvae of H. contortus and T. colubriformis on pasture were investigated by spreading faeces containing eggs on grass plots in October 1993, February and May 1994. Development of the eggs to the infective larvae occurred within one week and their survival times were 7 weeks in the 3 experiments. The potential for control by rotational grazing is discussed.
    Matched MeSH terms: Haemonchus/growth & development; Haemonchus/isolation & purification
  18. Field studies on the biological control of nematode parasites of sheep in the tropics, using the microfungus Duddingtonia flagrans
    Chandrawathani P, Jamnah O, Adnan M, Waller PJ, Larsen M, Gillespie AT
    Vet Parasitol, 2004 Mar 25;120(3):177-87.
    PMID: 15041093
    Long-term field studies were conducted on two government managed small ruminant research farms, located in different geo-climatic regions and approximately 300 km separate from each other, on Peninsula Malaysia. The Infoternak trial (48 weeks) and the Chalok trial (43 weeks) each compared nematode parasite control in separately managed groups of young sheep, either short-term rotationally grazed around a suite of 10 paddocks in addition to receiving a daily supplement of Duddingtonia flagrans spores (Fungus Group); or similar groups of sheep being rotationally grazed alone (Control Group). The prevailing weather conditions at Infoternak farm were of below average rainfall conditions for the most of the trial. As a consequence, only very low worm infections (almost exclusively Haemonchus contortus) were acquired by the 17 sets of tracer lambs that grazed sequentially with the experimental lambs. However on all except 2 occasions in the early part of the trial, the mean tracer worm burdens were significantly lower (P < 0.05) and the experimental lambs grew significantly better (P = 0.054) in the Fungus Group. Rainfall at Chalok farm during the course of the trial was also below average. As a consequence infectivity of pastures was assumed to be relatively low based on faecal egg counts (epg) of the experimental sheep, which following an anthelmintic treatment prior to allocation, remained very low in both treatment groups. Faecal egg counts of undosed replacement lambs in the latter half of the Chalok study, showed a progressive increase in the Control Group to levels exceeding 3000 epg, whereas the Fungus Group remained static at approximately 500 epg. These results show that the deployment of the nematophagous fungus, D. flagrans, can improve the level of parasite control of sheep in the tropics above that which can be achieved by the short-term rotational grazing strategy alone.
    Matched MeSH terms: Haemonchus/growth & development*; Haemonchus/microbiology
  19. Anthelmintic resistance in goats in peninsular Malaysia
    Dorny P, Claerebout E, Vercruysse J, Sani R, Jalila A
    Vet Parasitol, 1994 Dec;55(4):327-42.
    PMID: 7725626
    Ninety-six randomly selected farms, located throughout peninsular Malaysia, were surveyed for goat nematodes resistant to benzimidazoles (BZ). On 33 farms BZ resistance was demonstrated by means of an egg hatch assay. Haemonchus contortus was found to be the main species involved in anthelmintic resistance. There was a positive association between the frequency of anthelmintic treatments on a farm and the presence of benzimidazole resistance. To assess the value of the egg hatch assay, faecal egg count reduction (FECR) tests were also performed on 20 farms. On six farms the LD50 of thiabendazole (TBZ) was less than 0.10 micrograms ml-1 and the FECR higher than 95% and on ten farms with an LD50 TBZ of over 0.10 micrograms ml-1 a FECR of less than 95% was measured. On four farms the FECR was less than 95%, although the egg hatch assay showed LD50 TBZ values of less than 0.10 micrograms ml-1 and on two of these three farms a controlled efficacy test confirmed the presence of BZ resistant H. contortus. From these results it can be concluded that the egg hatch assay underestimated the true incidence of benzimidazole resistance. Levamisole resistance was detected with a FECR test on two of ten farms investigated.
    Matched MeSH terms: Haemonchus/drug effects*
  20. The establishment and development of Haemonchus contortus in goats
    Rahman WA, Collins GH
    Vet Parasitol, 1990 Mar;35(3):189-93.
    PMID: 2343536
    Twelve goats were inoculated with 40,000 third-stage Haemonchus contortus larvae and two were killed on each of Days 4, 7, 11, 14, 18 and 21 after inoculation (DAI). The number of worms that established, and the site of development were recorded. More worms established in the fundic, than in the middle or pyloric thirds of the abomasum. Early development occurred within the mucosa; emergence into the lumen started between 7 and 11 days after infection. By 4 DAI, all worms had completed the third moult to the L4 stage. At 11 DAI the majority of the worms were adults. A mean of 13.2% of the female worms had eggs in their uteri at 18 DAI; by 21 DAI more than half of the female worms had eggs in their uteri. The development of H. contortus was essentially similar to that described in sheep.
    Matched MeSH terms: Haemonchus/growth & development*
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