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Sample records for cooperia curticei railliet

  1. Effect of sainfoin (Onobrychis viciifolia) silage and hay on established populations of Haemonchus contortus and Cooperia curticei in lambs.

    PubMed

    Heckendorn, Felix; Häring, Dieter Adrian; Maurer, Veronika; Zinsstag, Jakob; Langhans, Wolfgang; Hertzberg, Hubertus

    2006-12-20

    The objective of the study was to examine the effect of dried and ensiled sainfoin (Onobrychis viciifolia) on established populations of Haemonchus contortus (abomasum) and Cooperia curticei (small intestine) in lambs under controlled conditions. Twenty-four parasite naïve lambs were inoculated with a single dose of infective larvae of these parasites 28 days prior to the start of the feeding experiment. Twenty-four days post-infection, 4 days prior to the start of the feeding experiment, animals were allocated to four groups according to egg excretion, live weight and sex. Groups A and B received sainfoin hay and control hay, respectively, for 16 days. Groups C and D were fed on sainfoin silage or control silage for the same period. Feeds were offered ad libitum and on the basis of daily refusals were supplemented with concentrate in order to make them isoproteic and isoenergetic. Individual faecal egg counts on a dry matter basis (FECDM) were performed every 3-4 days and faecal cultures and packed cell volume (PCV) measurements were done weekly. After 16 days of experimental feeding, all animals were slaughtered and adult worm populations were determined. The consumption of conserved sainfoin was associated with a reduction of adult H. contortus (47% in the case of hay, P<0.05; 49% in the case of silage, P=0.075) but had little effect on adult C. curticei. Compared to the controls, H. contortus specific FECDM was reduced by 58% (P<0.01) in the sainfoin hay group and by 48% (P=0.075) in the sainfoin silage group. For both sainfoin feeds FECDM specific to C. curticei were significantly decreased when compared to the control feeds (hay 81% and silage 74%, both tests P<0.001). Our data suggest that different mechanisms were responsible for the reduction in FECDM in response to feeding tanniferous fodder. For H. contortus, the decrease seemed to be due to a nematocidal effect towards adult H. contortus. In contrast for C. curticei, the reduction in FECDM appeared to

  2. Individual administration of three tanniferous forage plants to lambs artificially infected with Haemonchus contortus and Cooperia curticei.

    PubMed

    Heckendorn, Felix; Häring, Dieter Adrian; Maurer, Veronika; Senn, Markus; Hertzberg, Hubertus

    2007-05-15

    We investigated direct anthelmintic effects associated with the feeding of fresh tanniferous forages against established populations of Haemonchus contortus and Cooperia curticei in lambs. Twenty-four parasite naive lambs were inoculated with a single dose of infective larvae of these two parasites 27 days prior to the start of the feeding experiment. Lambs were individually fed with either chicory (Cichorium intybus), birdsfoot trefoil (Lotus corniculatus), sainfoin (Onobrychis viciifolia) or a ryegrass/lucerne mixture (control) for 17 days. Animals where then united to one flock and subjected to control feeding for another 11 days to test the sustainability of potentially lowered egg excretion generated by tanniferous forage feeding. When compared to the control, administration of all tanniferous forages was associated with significant reductions of total daily faecal egg output specific to H. contortus (chicory: 89%; birdsfoot trefoil: 63%; sainfoin: 63%; all tests P<0.05) and a tendency of reduced H. contortus worm burden (chicory: 15%; birdsfoot trefoil: 49% and sainfoin: 35% reduction). Irrespective of the condensed tannin (CT) containing fodder, no anthelmintic effects were found against C. curticei. Cessation of CT-feeding followed by non-CT control feeding did not result in a re-emergence of faecal egg counts based on faecal dry matter (FECDM) in any group, suggesting that egg output reductions are sustainable. The moderate to high concentrations of CTs in birdsfoot trefoil (15.2 g CTs kg(-1) dry matter (DM)) and sainfoin (26.1 g CTs kg(-1) DM) were compatible with the hypothesis that the antiparasitic effect of these forages is caused by their content of CTs. For chicory (3 g CTs kg(-1) DM), however, other secondary metabolites need to be considered. Overall, birdsfoot trefoil and in particular sainfoin seem promising candidates in contributing to an integrated control strategy against H. contortus not only by mitigating parasite related health

  3. Experimentally induced photosensitization in cattle with Cooperia pedunculata.

    PubMed

    Casteel, S W; Rowe, L D; Bailey, E M; Fiske, R A; Bridges, C W

    1988-04-01

    Photosensitization was induced in 2 Charolais heifers following administration of a mixture of air-dried, ground, green (75%) and dead (25%) leaves of the south Texas forb, Cooperia pedunculata, and subsequent exposure to sunlight. Plant material used in this study was collected from a pasture where natural cases of primary bovine photosensitization were occurring. Signs of photosensitization were observed in one heifer after 2 doses of plant material--10 g/kg on day 1 and 5 g/kg on day 2. Continued administration of plant material at 5 g/kg/d on days 3, 4, 7, 8, and 9 resulted in severe signs and lesions of photosensitization and death on day 23. A second heifer developed signs of mild photosensitization following administration of plant material at 1.7 g/kg/d for 4 days. This heifer recovered by day 18. Clinical and pathologic findings of this trial were consistent with the primary form of photosensitization observed in natural cases seen in cattle of south Texas exposed to this plant. PMID:3381477

  4. Regulatory networks and pathways in the bovine small intestine during Cooperia oncophora infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cooperia oncophora is an important parasitic nematode of cattle with a wide distribution in temperate areas. Twenty Holstein nematode-naïve bull calves were experimentally infected with approximately 100,000 infective L3s and infection was allowed to progress for 7, 14, 28, 42 days, respectively. Th...

  5. Mucin biosynthesis in the bovine goblet cell induced by Cooperia oncophora infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mucin hypersecretion is considered to be one of the most common components of the immune response to gastrointestinal nematode infection. However, investigations have not been conducted in the Cattle-Cooperia oncophora system to verify the findings largely derived from murine models. In this study, ...

  6. [The taxonomic position of nematodes in the genus Trichinella Railliet, 1895].

    PubMed

    Bessonov, A S

    1998-01-01

    In the author's opinion, the recent taxonomic revision of the genus Trichinella Railliet, 1895 (Pozio et al., 1992 and others) seems to be hasty and insufficiently substantiated. The proposed criteria for identification of new species, such as production of new-born larvae (PNBL) by Trichinella females in vitro, periods of development of nurse cells (DNC), index of reproductive capacity (IRC), resistance to freezing (RF), firstly, have a sufficient dispersion and are frequently very close (PNBL) to T. britovi, T. nativa, T. nelsoni, and T. pseudospiralis, DNC for these species. Secondly, these criteria are not always precise (one cannot agree with the fact that T. spiralis are not resistant to freezing). And, finally, it is impossible to be guided seriously by such criteria as the low or high significance of IRC or RF. According to the fifth criterion--the number of unique allozymic markers--two species are obviously distinguished: T. spiralis (6 markers) and T. pseudospiralis (12 markers). If the absence of capsule formation in case of T. psuedospiralis and the participation of birds in the life cycle of this parasite will be added to the above-mentioned, two species are again clearly distinguished: T. spiralis and T. pseudospiralis. Presently, it is necessary to classify the remaining species as varieties of subspecies of T. spiralis and to designate T. spiralis nativa, T. spiralis nelsoni, T. spiralis britovi, as recommended by the "Guidelines on Surveillance, Prevention, and Control of Trichinellosis" published by the WHO in 1988. PMID:9608199

  7. The vitamin D receptor and inducible nitric oxide synthase associated pathways in the development of acquired resistance to Cooperia oncophora infection in cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cooperia oncophora is an economically important gastrointestinal nematode in ruminants. Acquired resistance to Cooperia oncophora infection in cattle develops rapidly resulting from prior infections. Naïve cattle, when given a primary infection of high-dose infective L3 larvae, develop a strong immu...

  8. Photosensitization of cattle in southeast Texas: identification of phototoxic activity associated with Cooperia pedunculata.

    PubMed

    Rowe, L D; Norman, J O; Corrier, D E; Casteel, S W; Rector, B S; Bailey, E M; Schuster, J L; Reagor, J C

    1987-11-01

    A microbiological assay (Candida albicans) was used to screen plants in southeast Texas where bovine photosensitization (PS) of unknown cause was a recurring problem. Phototoxic activity was identified associated with dead leaf tips of Cooperia pedunculata, a native, perennial forb of the Amaryllis family (Amaryllidaceae) from central, southeast, and south Texas and parts of Mexico. A syndrome compatible with naturally occurring PS in cattle was induced in laboratory mice after oral administration of dead leaf material from C pedunculata. Availability and phototoxic activity of dead leaf material of C pedunculata corresponded with occurrence of PS in cattle. Seemingly, C pedunculata was involved in recurring PS. PMID:3434912

  9. Modelling Cooperia oncophora: Quantification of key parameters in the parasitic phase.

    PubMed

    Verschave, Sien H; Rose, Hannah; Morgan, Eric R; Claerebout, Edwin; Vercruysse, Jozef; Charlier, Johannes

    2016-06-15

    Cooperia oncophora is one of the most common intestinal nematodes in cattle. It is also the dose-limiting species for the most frequently used anthelmintics, and consequently, the species usually involved in reports of anthelmintic resistance. However, little information is available on its population dynamics, hindering the parameterisation of transmission models to support understanding of the impact of anthelmintic resistance, climate change and alternative control strategies on nematode epidemiology. This systematic review and meta-analysis provides estimates for key life history traits of the parasitic phase of C. oncophora and investigates potential influences of acquired immunity on these traits. PMID:27198786

  10. Splice variants and regulatory networks associated with host resistance to the intestinal worm Cooperia oncophora in cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To elucidate the molecular mechanisms of host resistance, we characterized the jejunal transcriptome of Angus cattle selected for parasite resistance for over 20 years in response to infection caused by the intestinal worm Cooperia oncophora. The transcript abundance of 56 genes, such as that of muc...

  11. A temporal shift in regulatory networks and pathways in the bovine small intestine during Cooperia oncophora infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cooperia oncophora is an important parasitic nematode of ruminants with a worldwide distribution. Twenty Holstein nematode-naïve bull calves were experimentally infected with approximately 100,000 L3 stage infective larvae for 7, 14, 28, 42 days, respectively. The experiment was conducted in order t...

  12. Analysis of the protective immune response following intramuscular vaccination of calves against the intestinal parasite Cooperia oncophora

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthelmintic resistance in the bovine parasite Cooperia oncophora is developing and spreading rapidly worldwide. Vaccination is therefore often put forward as a cost-effective alternative for chemical drugs. Recently we reported the successful evaluation of a double domain activation-associated secr...

  13. Cytoskeleton remodling and alterations in smooth muscle contractility in the bovine jejunum during the early stage of Cooperia oncophora infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gastrointestinal nematodes of the genus Cooperia are arguably the most important parasites of cattle. We characterized the bovine jejunal transcriptome in response to C. oncophora infection using RNA-seq technology. Approximately 71% of the 25,670 bovine genes were detected in the jejunal transcript...

  14. Gene expression of ABC transporters in Cooperia oncophora after field and laboratory selection with macrocyclic lactones.

    PubMed

    Tydén, Eva; Skarin, Moa; Höglund, Johan

    2014-12-01

    The most widespread helminth parasites of grazing cattle in northern Europe are the gastrointestinal nematodes Ostertagia ostertagi and Cooperia oncophora. Heavy reliance on the use of macrocyclic lactone (ML) in cattle has led to world-wide emergence of resistance to this drug class in C. oncophora. There is evidence that members of the ATP-binding cassette (ABC) transporter family, such as P-glycoproteins (P-gp) and multidrug-resistant proteins (MRP), play a role in resistance to ML. In this study gene expression of Con-pgp9, Con-pgp11, Con-pgp12, Con-pgp16 and Con-mrp1 was examined in two isolates of C. oncophora sharing the same genetic background but exposed to ML differently. For isolate one (Laboratory-selected), adult worms were recovered before and after treatment with ML in vivo. For isolate two (Field-selected), adult worms were collected from tracer animals that had never received anthelmintics themselves. One group grazed together with untreated animals and one group grazed with animals that received suppressive prophylactic treatment with ML at monthly intervals for up to two consecutive grazing seasons. Real-time PCR data demonstrated differences in gene expression after ML selection, with the highest constitutive expression levels for Con-pgp16 and Con-mrp1. Remarkably, the same pattern of increasing expression levels of the ABC transport genes was observed in both Laboratory- and Field-selected isolates, despite the Field-selected isolate not being directly exposed to ML. The higher expression levels of ABC transporters observed in the Field-selected isolate was thus not a response to direct exposure to ML, but rather appeared to reflect a genetic characteristic inherited from worms in the previous generation which had survived exposure to ML in the co-grazing treated animals. PMID:25619799

  15. Redescriptions of genera Raphidascaris Railliet et Henry, 1915 and Paranisakis Baylis, 1923 (Nematoda: Heterocheilidae), and Paracamallanus Yorke and Maplestone, 1926 (Nematoda: Camallanidae) from fish of Andhra Pradesh.

    PubMed

    Lakshmi, I R; Rao, K H; Shyamasundari, K

    1989-01-01

    The present paper deals with the redescriptions of the species of a nematode of the families, Heterocheilidae Railliet et Henry, 1915 and Camallanidae Railliet et Henry, 1915 from the intestine and stomach of marine fishes, Epinephelus areolatus (Forskål), Tachysurus tenuispinis (Day), Johnius diacantus (Lecépède), Ilisha filigera (Valenciennes), Pomadasys maculatus (Blooch). Dasyatis (Himantura) uarnak (Forskål), Pterois russelli Bennett, Scoliodon sorrakowah (Cuvier) and Carangoides malabaricus Bloch and Schneider from Visakhapatnam and Kakinada (Andhra Pradesh). Most of the characters tally with Raphidascaris chirocentri Yamaguti, 1935, Paranisakis pastinacae (Rud., 1819) Baylis, 1936 and Paracamallanus theraponis Kalyankar, 1970, but differs from it body measurements, oesophagus length, location of the nerve ring, length of the tridents, possession of striations, shape and position of the vulvar process and size of the eggs. Except for these minor variations, in all other characters there is agreement with above species. Because of the non-availability of the male, it is not possible to assign the present specimens to any of the known species of the genus Raphidascaris, Paranisakis and Paracamallanus. Hence these are referred as Raphidascaris sp., Paranisakis sp. and Paracamallanus sp. Dasyatis uarnak, Pterois russelli, Scoliodon sorrakowah and Carangoides malabaricus are new host records. Visakhapatnam and Kakinada are the new locality records. PMID:2487509

  16. Vaccination of calves against Cooperia oncophora with a double-domain activation-associated secreted protein reduces parasite egg output and pasture contamination.

    PubMed

    Vlaminck, Johnny; Borloo, Jimmy; Vercruysse, Jozef; Geldhof, Peter; Claerebout, Edwin

    2015-03-01

    With the increasing incidence of anthelmintic resistance worldwide, immunological control of worm infections through vaccination is often put forward as a rational and cost-effective alternative for anthelmintic drugs. In this study we report on the evaluation of a double-domain activation-associated secreted protein purified from the excretory-secretory material of the adult stage of the small intestinal parasite Cooperia oncophora as a vaccine antigen against this parasite. In a first experiment, calves were vaccinated three times i.m. with activation-associated secreted protein and Quil A adjuvant or with adjuvant alone, and subsequently challenged with a trickle infection of 25,000 infective larvae in total over 25 days. Vaccinated calves showed a significant reduction of 91% in their cumulative faecal egg counts and a significantly higher number of inhibited L4s present in their intestine compared with control animals. Furthermore, both female and male adult worms were significantly smaller in the vaccinated group than in the control group. In a second experiment, the vaccine antigen was further evaluated under field conditions. Calves were immunised as described above, followed by a natural challenge infection on pasture. Cooperia oncophora faecal egg counts in the vaccinated animals were reduced during the entire grazing period, resulting in a significant reduction in the cumulative faecal egg counts of 58.5%. Numbers of infective C. oncophora larvae were lower on plots grazed by vaccinated calves, with a reduction in mean pasture larval counts of 65% at housing. A significant reduction of 81.6% in total numbers of C. oncophora worms was shown in the vaccinated group compared with the control group. Taken together, the data highlight the protective capacity of the double-domain activation-associated secreted protein and the possibility of controlling C. oncophora infections through vaccination. PMID:25513963

  17. Transcriptome analyses reveal protein and domain families that delineate stage-related development in the economically important parasitic nematodes, Ostertagia ostertagi and Cooperia oncophora

    PubMed Central

    2013-01-01

    Background Cooperia oncophora and Ostertagia ostertagi are among the most important gastrointestinal nematodes of cattle worldwide. The economic losses caused by these parasites are on the order of hundreds of millions of dollars per year. Conventional treatment of these parasites is through anthelmintic drugs; however, as resistance to anthelmintics increases, overall effectiveness has begun decreasing. New methods of control and alternative drug targets are necessary. In-depth analysis of transcriptomic data can help provide these targets. Results The assembly of 8.7 million and 11 million sequences from C. oncophora and O. ostertagi, respectively, resulted in 29,900 and 34,792 transcripts. Among these, 69% and 73% of the predicted peptides encoded by C. oncophora and O. ostertagi had homologues in other nematodes. Approximately 21% and 24% were constitutively expressed in both species, respectively; however, the numbers of transcripts that were stage specific were much smaller (~1% of the transcripts expressed in a stage). Approximately 21% of the transcripts in C. oncophora and 22% in O. ostertagi were up-regulated in a particular stage. Functional molecular signatures were detected for 46% and 35% of the transcripts in C. oncophora and O. ostertagi, respectively. More in-depth examinations of the most prevalent domains led to knowledge of gene expression changes between the free-living (egg, L1, L2 and L3 sheathed) and parasitic (L3 exsheathed, L4, and adult) stages. Domains previously implicated in growth and development such as chromo domains and the MADF domain tended to dominate in the free-living stages. In contrast, domains potentially involved in feeding such as the zinc finger and CAP domains dominated in the parasitic stages. Pathway analyses showed significant associations between life-cycle stages and peptides involved in energy metabolism in O. ostertagi whereas metabolism of cofactors and vitamins were specifically up-regulated in the parasitic

  18. The use of parasites as bioindicators of pesticide exposure

    PubMed Central

    Sabo, Rastislav; Sabová, Lucia; Legáth, Jaroslav

    2009-01-01

    Organisms used in risk assessment of pesticides must be the most sensitive ones to pesticides exposure. The aim of this study was to observe the effect of two commercial pesticide products (containing glyphosate and tolylfluanid) to larval stages of parasites Cooperia curticei, Ostertagia circumcincta, Haemonchus contortus and Trichostrongylus axei. There were two concentrations tested for each product vs. control group. Larvae (500 individuals/Petri dish) were incubated at 27 °C and observed daily for 42 days. We found out that T. axei larvae are the most resistant ones to tolylfluanid exposure – there was no statistical significance in any concentration tested after 42 days of tolylfluanid exposure. 100% of dead larvae were found on 33rd day of experiment at higher concentration, resp. on 37th day at lower tested concentration of glyphosate. C. curticei, O. circumcincta and H. contortus showed similar statistical significance in both pesticides tested (there was high statistical significance (p<0.0001) at both concentrations of glyphosate and only at higher tested concentration of tolylfluanid). C. curticei and H. contortus larvae were found dead, spiral shaped and without movement at all concentrations tested, spiral shape was not observed in other two tested larvae. O. circumcincta larvae reacted to pesticides exposure very quickly; rapid death was recorded on second day of experiment at both concentrations of glyphosate and at higher tested concentration of tolylfluanid. From four tested small ruminant parasites (L3), O. circumcincta larvae seem to be the most sensitive ones and need further research. PMID:21217852

  19. Lack of efficacy of monepantel against Trichostrongylus colubriformis in sheep in Brazil.

    PubMed

    Cintra, M C R; Teixeira, V N; Nascimento, L V; Sotomaior, C S

    2016-01-30

    Multiple drug resistance of nematodes against anthelmintics has become one of the most important economic problems in sheep production worldwide. The aim of this experiment was to evaluate the efficacy of monepantel (2.5mg/kg) against gastrointestinal nematodes in fecal egg count reduction test (FECRT) and controlled efficacy test (CT) in naturally infected sheep. We used 30 sheep for the FECRT and 20 sheep for the CT, equally divided into control and treated groups. In the FECRT, the reduction was 98%. Larval identification of pre-treatment coprocultures revealed 100% Haemonchus spp. for both control and treated groups. Post-treatment culture of treated sheep was 100% Oesophagostomum spp., but only few larvae were recovered. In the control group, they were 99% Haemonchus spp and 1% Oesophagostomum spp. larvae. Based on the FECRT, Haemonchus spp. was considered susceptible to monepantel. The efficacy of monepantel in the CT against Haemonchus contortus and Trichostrongylus axei was 100% and against Cooperia curticei was 99.7%. For Trichostrongylus colubriformis, the efficacy was -21.5%. In both treated and untreated animals, Oesophagostomum columbianum was recovered from the large intestines. Based on FECRT and CT and in accordance with WAAVP standards, monepantel was ineffective against T. colubriformis and O. columbianum, but effective against H. contortus, T. axei and C. curticei in the studied flock. PMID:26801587

  20. [CIRCULATION OF DIROFILARIA REPENS (RAILLIET ET HENRY, 1911) IN THE ARID ZONE OF SOUTHERN RUSSIA].

    PubMed

    Varlamova, A I; Arkhipov, I A

    2016-01-01

    The prevalence of dirofilariasis was studied in dogs from the urban and rural areas in Southern Russia. The high prevalence of Dirofilaria repens infection were established among the dogs in the Republic of Kalmykia. The blood samples from 328 dogs were tested; D. repens infection was detected in 23.6 and 15.5% of the rural and urban dogs, respectively. The highest prevalence of D. repens infection was noted in of 4-6-year-old dogs. Dogs aged 0, 1-3, 4-6 7-9, and more 10 years were infected in 0, 26.3, 33.3, 29.4, and 28.5% of cases, respectively. PMID:27405212

  1. Real-time PCR/DNA melting curve-based assay to identify individual strongylid larvae recovered from ovine faecal cultures.

    PubMed

    Knight, Jacqueline S; Bisset, Stewart A

    2015-12-15

    A closed-tube real-time PCR (RT PCR) method was developed to identify individual strongylid nematode larvae recovered from ovine faecal cultures. The method builds on an earlier conventional PCR assay established by our group and similarly targets species-specific sequence motifs in the ITS-2 region of ribosomal DNA. The new procedure combines RT PCR with DNA melting curve analyses to identify species-specific amplicons, thus avoiding the need to undertake gel electrophoresis. As with the earlier method, it involves two sets of species-specific reactions. The first targets Haemonchus contortus, Teladorsagia circumcincta, Trichostrongylus colubriformis, Nematodirus spathiger and Oesophagostomum venulosum while the second targets Trichostrongylus axei, Trichostrongylus vitrinis, Cooperia curticei and Chabertia ovina. With two exceptions, all the DNA primers employed in the new assay were among those described and tested in developing the earlier assay. The exceptions are the forward "generic" primer, which was re-designed to generate smaller amplicon sizes more suitable for melting curve analyses, and the T. axei-specific primer, which was modified to achieve a higher amplicon melt temperature to enable larvae of this species to be more readily differentiated from those of C. curticei. The melt temperature range for amplicons representing each of the species targeted was determined using lysates derived from both microscopically identified adult male worms (2-12/species), as well as 30 larvae of each of the species which were derived from at least 6 different geographical locations throughout New Zealand. The new assay potentially provides a simpler, faster method to identify individual ovine strongylid larvae for downstream applications than was provided by the earlier conventional PCR assay. PMID:26526096

  2. An evaluation of ethyl-6-ethoxybenzothiazole-2-carbamate (Sch 18099) for anthelmintic activity in domestic animals.

    PubMed

    Panitz, E

    1977-03-01

    Ethyl-6-ethoxybenzothiazole-2-carbamate (Sch 18099) was evaluated for efficacy against natural helminth infections in ponies, pigs, lambs and chickens. Sixteen critical trials were conducted in ponies at dosages of 15 to 150 mg/kg. At 15 mg/kg, efficacy against adult and larval Oxyuris equi was 100% and 91% and against small strongyles it was 98%. Efficacy levels were 95% against Strongylus vulgaris and S. edentatus at the 20 mg/kg dosage. In two trials at 100 mg/kg efficacy against Parascaris equorum was 77%. No efficacy was observed against Gastrophilus spp. or Anoplocephala spp. In swine single oral doses of 10 to 100 mg/kg were not effective. 500 ppm Sch 18099 in the diet for seven days resulted in 100% efficacy against Ascaris suum and Trichuris suis but had no effect on Stongyloides ransomi. Efficacy at 250 ppm against A. suum was 77%. Efficacy at 200 mg/kg in lambs was greater than 90% for Haemonchus contortus, Trichostrongylus axei, Marshallagia marshalli, Bunostomum trignocephalum, Oesophagostomum columbianum, Trichuris ovis, and Chabertia spp. Efficacy was less than 80% for Trichostrongylus vitrinus, Nematodirus filicollis, Ostertagia circumcinta and Cooperia curticei. Except for O. circumcinta and C. curticei, drug efficacy was reduced for these worms in lambs treated at 100 mg/kg. Efficacies of 14.3-89% against Ascaridia galli were obtained with dietary levels of 125-1000 ppm Sch 18099 fed for 7 days. Efficacy of 100% was recorded against Heterakis gallinarum at the 1000 ppm dietary drug level. PMID:864223

  3. Experimental infection of selected arthropods with spirurid nematodes Spirocerca lupi Railliet & Henry, 1911 and Gongylonema ingluvicola Molin, 1857.

    PubMed

    Mukaratirwa, S; Pillay, E; Munsammy, K

    2010-12-01

    Gongylonema ingluvicola and Spirocerca lupi are spirurid nematodes that require arthropod intermediate hosts in order to complete their life cycle. Beetles of the family Scarabaeidae are reported to serve as intermediate hosts for both these parasites. In this study selected species of beetles of the family Scarabaeidae as well as other groups of arthropods were screened for susceptibility to infection with S. lupi and G. ingluvicola. Arthropods were exposed to infective eggs of both parasites for a determined period of time and dissected/digested to determine the presence or absence of pre-infective and infective larvae. All the five species of dung beetles exposed to infection with S. lupi, namely, Pachylomerus femoralis, Scarabaeus rugosus, Gymnopleurus humanus, Kheper nigroaeneus and Anachalcos convexus were susceptible and, of the two species exposed to G. ingluvicola, only Gy. humanus was susceptible. Spirocerca lupi eggs developed in millipede species, Daratoagonus cristulatus, and remained as encysted larvae, while in Orthoporoides kyrhocephalus no development was observed. Spirocerca lupi larvae were not detected in the cricket species Gryllus assimilis, or the cockroach species Periplaneta americana, and, similarly, G. ingluvicola larvae were not detected in the millipede species O. kyrhocephalus. The difference in the susceptibility of the arthropods to the two parasite species may depend on their feeding biology. PMID:20132587

  4. A multiplex PCR-based method to identify strongylid parasite larvae recovered from ovine faecal cultures and/or pasture samples.

    PubMed

    Bisset, S A; Knight, J S; Bouchet, C L G

    2014-02-24

    A multiplex PCR-based method was developed to overcome the limitations of microscopic examination as a means of identifying individual infective larvae from the wide range of strongylid parasite species commonly encountered in sheep in mixed sheep-cattle grazing situations in New Zealand. The strategy employed targets unique species-specific sequence markers in the second internal transcribed spacer (ITS-2) region of ribosomal DNA of the nematodes and utilises individual larval lysates as reaction templates. The basic assay involves two sets of reactions designed to target the ten strongylid species most often encountered in ovine faecal cultures under New Zealand conditions (viz. Haemonchus contortus, Teladorsagia circumcincta, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Cooperia curticei, Cooperia oncophora, Nematodirus spathiger, Chabertia ovina, and Oesophagostomum venulosum). Five species-specific primers, together with a pair of "generic" (conserved) primers, are used in each of the reactions. Two products are generally amplified, one by the generic primer pair regardless of species (providing a positive PCR control) and the other (whose size is indicative of the species present) by the appropriate species-specific primer in combination with one or other of the generic primers. If necessary, any larvae not identified by these reactions can subsequently be tested using primers designed specifically to detect those species less frequently encountered in ovine faecal cultures (viz. Ostertagia ostertagi, Ostertagia leptospicularis, Cooperia punctata, Nematodirus filicollis, and Bunostomum trigonocephalum). Results of assays undertaken on >5500 nematode larvae cultured from lambs on 16 different farms distributed throughout New Zealand indicated that positive identifications were initially obtained for 92.8% of them, while a further 4.4% of reactions gave a generic but no visible specific product and 2.8% gave no discernible

  5. Effects of age, sex, lactation and social dominance on faecal egg count patterns of gastrointestinal nematodes in farmed eland (Taurotragus oryx).

    PubMed

    Vadlejch, J; Kotrba, R; Čadková, Z; Růžičková, A; Langrová, I

    2015-10-01

    The eland is a large African antelope that can be bred in a temperate climate, under similar conditions and production systems as cattle. However, knowledge of parasites in farmed elands outside the area of their native habitat is still limited, and information concerning factors that influence these parasites is lacking. Therefore, faecal samples from an entire herd of elands, including calves and adult females and males, were examined monthly over a one year period. Almost 84% of the animals were found to be positive for gastrointestinal nematodes. Strongyle-type eggs were most frequently detected (prevalence 75%), followed by Capillaria sp., Nematodirus sp. and Trichuris sp. eggs. Following culturing eggs to infective larvae, Teladorsagia sp., Trichostrongylus sp., Nematodirus sp., Cooperia sp. and Oesophagostomum sp. were identified. Following necropsy of two calves that died during the study one abomasal nematode (Teladorsagia circumcincta), five small intestinal nematode species (Nematodirus helvetianus, N. spathiger, Cooperia oncophora, C. curticei and Capillaria bovis) and two large intestinal nematodes (Oesophagostomum venulosum and Trichuris ovis) were recovered. From these findings, it is evident that the eland harbours nematodes that are typical for domestic cattle and small ruminants. Morphological and morphometric analyses of recovered nematodes revealed that these parasites do not require any special morphological adaptation to establish infection in elands. The faecal output of strongyle-type and Nematodirus sp. eggs was seasonal, with the highest egg production taking place during spring and summer. Calves had higher faecal egg counts (for all the monitored nematode species) than adults did. Lactation in females was significantly (P<0.0001) associated with higher strongyle nematode egg shedding. Social dominance also affected faecal egg count patterns. The lower the hierarchical position among adults (regardless of sex), the higher the risk of

  6. Haemonchus longistipes Railliet & Henry, 1909 (Nematoda, Trichostrongylidae) from the Egyptian dromedary, Camelus dromedarius (Artiodactyla: Camelidae), first identification on the basis of light and ultrastructural data.

    PubMed

    Morsy, Kareem; Bashtar, Abdel-Rahman; Fol, Mona; Yehia, Salma

    2014-12-01

    Haemonchus longistipes is a gastrointestinal abomasal nematode which is one of the most prevalent and pathogenic parasites infesting the stomach of ruminants. On the basis of light and ultrastructural data, the objective of the present study was to introduce a first identification of the cameline haemonchosis caused by H. longistipes. Abomasa of 42 Egyptian camels Camelus dromedarius (Artiodactyla: Camelidae) were collected monthly from September 2013 to April 2014 from the main slaughter house of Cairo, Egypt. Adult male and female nematode worms were recovered from 26 (62%) specimens of the examined abomasa. The parasites were of yellow color; the body was filiform (slender) tapered towards the anterior end in male and towards both ends in female. Buccal capsules absent, the buccal cavity was small with a conspicuous dorsal lancet extended from dorsal wall. The cervical papillae were prominent and spine-like. The body length of the female worm was 16.6-20.5 (18.5 ± 0.3) mm. The anterior end to the cervical papillae was 3.19-4.30 (4.12 ± 0.5) mm. The vulva of the female had a linguiform process or flap, the tail is without a spine, and the anal pore at the posterior end of the body had a simple dorsal rim. The body of male was 10.4-14.7 (13.9 ± 2.0) mm in length. The male bursa had elongated lobes supported by long, slender rays. The small dorsal lobe was asymmetrical with Y-shaped dorsal rays. The spicules were long with a length of 0.52-0.54 (0.53 ± 0.05) mm, each provided with a small barb and pore near its extremity. Synlophe was bilaterally and dorsoventrally symmetrical; it extended from cephalic expansion over anterior 50% of prebursal or prevulvar body and consisted of a maximum of 42 ridges. The described species herein was compared with the three morphologically similar species Haemonchus mitchelli, Haemonchus okapiae, and H. longistipes with their synlophes consist of 42 ridges distributed over the anterior half of the body. These species can be separated by unique structural characteristics of their synlophes, spicules, and copulatory bursa. The most morphologically similar species to the recovered worm was H. longistipes. Also, some of the parameters with regard to morphology and morphometry of this parasite were described for the first time. PMID:25273629

  7. Development of a multiplex real-time PCR for differentiating and quantifying eggs of Haemonchus contortus, Ostertagia ostertagi, and Cooperia oncophora using fecal eggs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite recent assay development for both egg and larval stages of trichostrongyles nematodes, there is still a need for a quantitative assay which can differentiate the eggs of economically important trichostrongyles in a rapid manner. These morphologically identical eggs can be differentiated usin...

  8. Efficacy of a combined oral formulation of derquantel-abamectin against the adult and larval stages of nematodes in sheep, including anthelmintic-resistant strains.

    PubMed

    Little, Peter R; Hodge, Andrew; Maeder, Steven J; Wirtherle, Nicole C; Nicholas, David R; Cox, George G; Conder, George A

    2011-09-27

    and respiratory nematode parasites of sheep, as follows: ≥ 98.9% efficacy against Haemonchus contortus (adult and L4); Teladorsagia circumcincta (adult, L4 and hypobiotic L4); Teladorsagia trifurcata (L4); Trichostrongylus axei (adult and L4); Trichostrongylus colubriformis (adult and L4); Trichostrongylus falculatus (adult); Trichostrongylus rugatus (adult); Trichostrongylus vitrinus (adult and L4); Cooperia curticei (adult and L4); Cooperia oncophora (adult and L4); Nematodirus spathiger (adult); Nematodirus battus (adult); Nematodirus spp. (hypobiotic L4); Strongyloides papillosus (adult); Strongyloides spp. (L4); Chabertia ovina (adult); Oesophagostomum venulosum (adult); Dictyocaulus filaria (adult); and Protostrongylus rufescens (adult); ≥ 97.0% efficacy against Trichuris ovis (adult); and ≥ 95.9% efficacy against T. trifurcata (adult). Derquantel-abamectin is a highly effective combination anthelmintic, which will provide an important new tool for controlling helminths of sheep when used in conjunction with sustainable drenching practices. PMID:21684691

  9. 21 CFR 520.905c - Fenbendazole paste.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... lungworms (Dictyocaulus viviparus), stomach worms (Haemonchus contortus, Ostertagia ostertagi, Trichostrongylus axei), and intestinal worms (Bunostomum phlebotomum, Nematodirus helvetianus, Cooperia punctata,...

  10. 21 CFR 520.905c - Fenbendazole paste.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... lungworms (Dictyocaulus viviparus), stomach worms (Haemonchus contortus, Ostertagia ostertagi, Trichostrongylus axei), and intestinal worms (Bunostomum phlebotomum, Nematodirus helvetianus, Cooperia punctata,...

  11. 21 CFR 520.905c - Fenbendazole paste.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... lungworms (Dictyocaulus viviparus), stomach worms (Haemonchus contortus, Ostertagia ostertagi, Trichostrongylus axei), and intestinal worms (Bunostomum phlebotomum, Nematodirus helvetianus, Cooperia punctata,...

  12. 21 CFR 520.905c - Fenbendazole paste.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... lungworms (Dictyocaulus viviparus), stomach worms (Haemonchus contortus, Ostertagia ostertagi, Trichostrongylus axei), and intestinal worms (Bunostomum phlebotomum, Nematodirus helvetianus, Cooperia punctata,...

  13. 21 CFR 520.905c - Fenbendazole paste.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... lungworms (Dictyocaulus viviparus), stomach worms (Haemonchus contortus, Ostertagia ostertagi, Trichostrongylus axei), and intestinal worms (Bunostomum phlebotomum, Nematodirus helvetianus, Cooperia punctata,...

  14. 21 CFR 520.1192 - Ivermectin paste.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...): Dictyocaulus arnfieldi; Intestinal Threadworms (adults): Strongyloides westeri; Summer Sores caused by.... colubriformis, Cooperia oncophora, C. punctata, Nematodirus helvetianus, Bunostomum phlebotomum,...

  15. 21 CFR 520.1192 - Ivermectin paste.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...): Dictyocaulus arnfieldi; Intestinal Threadworms (adults): Strongyloides westeri; Summer Sores caused by.... colubriformis, Cooperia oncophora, C. punctata, Nematodirus helvetianus, Bunostomum phlebotomum,...

  16. 21 CFR 520.1192 - Ivermectin paste.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...): Dictyocaulus arnfieldi; Intestinal Threadworms (adults): Strongyloides westeri; Summer Sores caused by.... colubriformis, Cooperia oncophora, C. punctata, Nematodirus helvetianus, Bunostomum phlebotomum,...

  17. 21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms...

  18. 21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms...

  19. 21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms...

  20. 21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms...

  1. 21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms...

  2. Comparative analyses of transcriptomic profiles of the bovine small intestine in response to both a primary infection and a drug-attenuated reinfection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cooperia oncophora is an economically important gastrointestinal nematode in ruminants. Acquired resistance to Cooperia oncophora infection in cattle develops rapidly as a result of prior infections. Naïve cattle, when given a primary infection of high-dose infective L3 larvae, develop a strong immu...

  3. 21 CFR 520.1242a - Levamisole powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia); intestinal worms (Trichostrongylus... the following adult nematode infections: Stomach worms (Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei); intestinal worms (T. longispicularis, Cooperia oncophora, C. punctata,...

  4. 21 CFR 558.360 - Morantel tartrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (ii) Goats. For removal...

  5. 21 CFR 558.315 - Levamisole hydrochloride (equivalent).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... Treatment of the following gastrointestinal worms and lung worm infections; stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus Cooperia, Nematodirus, Bunostomum.... Treatment of the following nematode infections: large roundworms (Ascaris suum), nodular...

  6. 21 CFR 558.360 - Morantel tartrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (ii) Goats. For removal...

  7. 21 CFR 520.1242a - Levamisole powder for oral solution.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Indications for use—(A) Effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia); intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum...: Stomach worms (Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei); intestinal worms...

  8. 21 CFR 520.1450a - Morantel tartrate bolus.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (3) Limitations. Conditions...

  9. 21 CFR 520.1450a - Morantel tartrate bolus.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (3) Limitations. Conditions...

  10. 21 CFR 520.1242f - Levamisole hydrochloride gel.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... with the following nematodes: Large roundworms (Ascaris suum), nodular worms (Oesophagostomum...

  11. 21 CFR 558.360 - Morantel tartrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (ii) Goats. For removal...

  12. 21 CFR 520.1450a - Morantel tartrate bolus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (3) Limitations. Conditions...

  13. 21 CFR 520.1242f - Levamisole hydrochloride gel.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... with the following nematodes: Large roundworms (Ascaris suum), nodular worms (Oesophagostomum...

  14. 21 CFR 520.1242f - Levamisole hydrochloride gel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... with the following nematodes: Large roundworms (Ascaris suum), nodular worms (Oesophagostomum...

  15. 21 CFR 520.1242f - Levamisole hydrochloride gel.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... with the following nematodes: Large roundworms (Ascaris suum), nodular worms (Oesophagostomum...

  16. 21 CFR 522.1242 - Levamisole.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... is used as an anthelmintic in cattle for treatment of the following parasites: stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus... used as an anthelmintic in cattle for treatment of the following parasites: stomach worms...

  17. 21 CFR 520.1242a - Levamisole powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia); intestinal worms (Trichostrongylus... the following adult nematode infections: Stomach worms (Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei); intestinal worms (T. longispicularis, Cooperia oncophora, C. punctata,...

  18. 21 CFR 520.1242f - Levamisole hydrochloride gel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms... with the following nematodes: Large roundworms (Ascaris suum), nodular worms (Oesophagostomum...

  19. 21 CFR 558.360 - Morantel tartrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (ii) Goats. For removal...

  20. 21 CFR 520.1450a - Morantel tartrate bolus.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (3) Limitations. Conditions...

  1. 21 CFR 558.360 - Morantel tartrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (ii) Goats. For removal...

  2. 21 CFR 520.1450a - Morantel tartrate bolus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... control of mature gastrointestinal nematode infections of cattle including stomach worms (Haemonchus spp., Ostertagia spp., Trichostrongylus spp.), worms of the small intestine (Cooperia spp., Trichostrongylus spp., Nematodirus spp.), and worms of the large intestine (Oesophagostomum radiatum). (3) Limitations. Conditions...

  3. 21 CFR 520.2380c - Thiabendazole bolus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Trichostrongylus spp., Haemonchus spp., Nematodirus spp., Ostertagia spp., and Oesophagostomum radiatum). (b...., Nematodirus spp., Ostertagia spp., and Oesophagostomum radiatum). Control of infections with Cooperia spp. (b...., Nematodirus spp., Bunostomum spp., Strongyloides spp., Chabertia spp., and Oesophagostomum spp. ); also...

  4. 21 CFR 520.2380c - Thiabendazole bolus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Trichostrongylus spp., Haemonchus spp., Nematodirus spp., Ostertagia spp., and Oesophagostomum radiatum). (b.... Control of severe infections of gastrointestinal roundworms (genera Trichostrongylus spp., Haemonchus spp... sheep and goats (general Trichostrongylus spp., Haemonchus spp., Ostertagia spp., Cooperia...

  5. 21 CFR 520.2380a - Thiabendazole top dressing and mineral protein block.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Thiabendazole top dressing and mineral protein... § 520.2380a Thiabendazole top dressing and mineral protein block. (a) Chemical name. 2-(4-Thiazolyl..., Ostertagia and Cooperia). (iv) Limitations. Administer to cattle on pasture or range accustomed to...

  6. 21 CFR 520.2380a - Thiabendazole top dressing and mineral protein block.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Thiabendazole top dressing and mineral protein... § 520.2380a Thiabendazole top dressing and mineral protein block. (a) Chemical name. 2-(4-Thiazolyl..., Ostertagia and Cooperia). (iv) Limitations. Administer to cattle on pasture or range accustomed to...

  7. 21 CFR 520.2380a - Thiabendazole top dressing and mineral protein block.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Thiabendazole top dressing and mineral protein... § 520.2380a Thiabendazole top dressing and mineral protein block. (a) Chemical name. 2-(4-Thiazolyl..., Ostertagia and Cooperia). (iv) Limitations. Administer to cattle on pasture or range accustomed to...

  8. 21 CFR 520.2380a - Thiabendazole top dressing and mineral protein block.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Thiabendazole top dressing and mineral protein... § 520.2380a Thiabendazole top dressing and mineral protein block. (a) Chemical name. 2-(4-Thiazolyl..., Ostertagia and Cooperia). (iv) Limitations. Administer to cattle on pasture or range accustomed to...

  9. 21 CFR 520.2380a - Thiabendazole top dressing and mineral protein block.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Thiabendazole top dressing and mineral protein... § 520.2380a Thiabendazole top dressing and mineral protein block. (a) Chemical name. 2-(4-Thiazolyl..., Ostertagia and Cooperia). (iv) Limitations. Administer to cattle on pasture or range accustomed to...

  10. Nitroxynil. Anthelmintic activity in cattle following subcutaneous injection.

    PubMed

    Wellington, A C

    1978-07-01

    Nitroxynil injected subcutaneously at 10 mg/kg live mass achieved Class A efficacy when evaluated by the non parametric method against adult Fasciola gigantica. Haemonchus placei, Bonustomum phlebotomum and Oesophagostomum radiatum in cattle. The compound was not effective against adult Cooperia spp. at the same dosage. PMID:569707

  11. New Aspidoderidae species parasite of Didelphis aurita (Mammalia: Didelphidae): a light and scanning electron microscopy approach.

    PubMed

    Chagas-Moutinho, V A; Sant'anna, V; Oliveira-Menezes, A; De Souza, W

    2014-02-01

    Nematodes of the family Aspidoderidae (Nematoda: Heterakoidea) Skrjabin and Schikobalova, 1947, are widely distributed in the Americas. The family Aspidoderidae includes the subfamilies Aspidoderinae Skrjabin and Schikobalova, 1947, and Lauroiinae Skrjabin and Schikobalova, 1951. These two subfamilies are delineated by the presence or absence of cephalic cordons at the anterior region. The nematodes in the subfamily Aspidoderinae, which includes the genus AspidoderaRailliet and Henry, 1912, are represented by nematodes with anterior cephalic cordons at the anterior end. The nematodes of the genus AspidoderaRailliet and Henry, 1912, are found in the cecum and large intestine of mammals of the orders Edentata, Marsupialia and Rodentia. Species within this genus have many morphological similarities. The use of scanning electron microscopy allows the specific characterization of the species within this genus. In the present work, we describe a new species of Aspidodera parasite of the large intestine of Didelphis aurita (Mammalia: Didelphidae) Wied-Neuwied, 1826, collected from Cachoeiras de Macacu, Rio de Janeiro. The combination of light and scanning electron microscopy allowed us a detailed analysis of this nematode. PMID:24129095

  12. Seasonal variations in the numbers of trichostrongylid nematode eggs and their larvae in the faeces of farmed goats in Malaysia.

    PubMed

    Rahman, W A

    1992-04-01

    Faecal worm egg counts of goats from two farms in Penang Island, West Malaysia, were monitored over a period of 14 months. The faecal egg count pattern followed that of total rainfall. The humid tropical environment was favourable for the development of various species of trichostrongylid nematodes, namely Haemonchus contortus, Trichostrongylus spp., Oesophagostomum spp. and Cooperia spp. Generally, H. contortus was observed to be the predominant species, more so in the monsoon months of the year. PMID:1615628

  13. Further description of Aspidodera raillieti (Nematoda: Aspidoderidae) from Didelphis marsupialis (Mammalia: Didelphidae) by light and scanning electron microscopy.

    PubMed

    Chagas-Moutinho, V A; Oliveira-Menezes, A; Cárdenas, M Q; Lanfredi, R M

    2007-10-01

    Nematodes of the family Aspidoderidae (Nematoda: Heterakoidea) Freitas 1956 are widely distributed from Americas. The species of the genus Aspidodera Railliet and Henry 1912 are parasites of mammals of the orders Edentata, Marsupialia, and Rodentia. In the present work, Aspidodera raillieti (L. Travassos, Mem Inst Oswaldo Cruz 5(3):271-318, 1913), collected from the large intestine of Didelphis marsupialis (Mammalia: Didelphidae) from Valle del Cauca, Colombia, is redescribed. The association of light and scanning electron microscopy (SEM) allowed a detailed analysis of the morphology and ultrastructure of this nematode. Some taxonomic features, such as cephalic region, topography of the cuticle, sucker, spicules, posterior end of males, localization of vulva, the anus, and posterior end of females were observed. Important structures such as amphid, details of cephalic region, phasmid, and number and localization of caudal papillae are documented by SEM, for the first time adding characters to identify this species. Colombia is a new geographical record for A. raillieti. PMID:17622560

  14. Human intestinal sarcosporidiosis: report of six cases.

    PubMed

    Bunyaratvej, S; Bunyawongwiroj, P; Nitiyanant, P

    1982-01-01

    Specimens of resected small intestine from six patients aged 3 to 70 years with acute enteritis contained sexual forms of sarcosporidia. Histopathologically, the diagnoses were either segmental eosinophilic enteritis or segmental necrotizing enteritis. The presence of sarcosporidia in market beef (Bos indicus), and the patients' habit of eating the beef uncooked in the form of chili-hot dishes, suggest that the species is an ox-man parasite similar to Sarcocystis hominis (Railliet and Lucet, 1891) Dubey, 1976. Presence of numerous Gram-positive bacilli in segmental necrotizing enteritis suggests an interplay between two etiological agents in producing the hosts' inflammatory responses. Five patients recovered after resection, but one died due to extensive necrosis of the intestinal wall and leakage at the site of anastomosis. Only conventional antibiotics were given after the operations. None of the five surviving patients has had recurrent enteritis for at least 1 year. PMID:6800273

  15. Aspidoderidae from North America, with the description of a new species of Aspidodera (Nematoda: Heterakoidea).

    PubMed

    Jiménez-Ruiz, F Agustín; Gardner, Scott L; Varela-Stokes, Andrea S

    2006-08-01

    Aspidodera sogandaresi n. sp. (Heterakoidea: Aspidoderidae) from Dasypus novemcinctus Linnaeus, 1758 is herein described. This nematode occurs in armadillos from as far south as the canal zone of Panama, north through central Mexico, and into the southern United States. Previously identified as Aspidodera fasciata (Schneider, 1866), this new species has blunt projections on the lips and lateral expansions at the distal tips of the spicules, whereas A. fasciata has conspicuous digitiform projections on the lips, and a terminal round expansion at the tips of the spicules. Other species of the family present in North America include Aspidodera binansata Railliet and Henry, 1913; Aspidodera vazi Proença, 1937; and Lauroia trinidadensis Cameron, 1939. PMID:16995403

  16. Larvae of Contracaecum sp. (Nematoda: Anisakidae) in the threatened freshwater fish Sandelia capensis (Anabantidae) in South Africa.

    PubMed

    Moravec, Franti Ek; van Rensburg, Candice Jansen; Van As, Liesl L

    2016-08-01

    Third-stage larvae of the nematode genus Contracaecum Railliet et Henry, 1912 (Contracaecum sp.) were, for the first time, recorded from the abdominal cavity of the threatened endemic freshwater fish Sandelia capensis (Cuvier) in South Africa. The larval morphology indicated that they belong to a species of which the adults are parasitic in fish-eating birds. Although the nematode seems to be a common parasite of S. capensis in the locality under study (prevalence 23%), the low intensity of infection recorded (1 to 4) and the generally known low pathogenicity of Contracaecum larvae in fish indicate that this parasite probably does not represent a danger to the local population of this threatened fish species. PMID:27503922

  17. Redescription, generic allocation and synonymy of Decorataria magnilabiata (Molin, 1860) n. comb. (Nematoda: Spirurida: Acuariidae), a parasite of the roseate spoonbill Platalea ajaja L. (Aves: Threskiornithidae) in South America.

    PubMed

    Mutafchiev, Yasen; Georgiev, Boyko B

    2011-09-01

    Decorataria magnilabiata (Molin, 1860) n. comb. is proposed for Dispharagus magnilabiatus Molin, 1860 [= Acuaria (Cheilospirura) magnilabiata (Molin, 1860) Railliet, Henry & Sisoff, 1912; Cheilospirura magnilabiata (Molin, 1860) Stiles & Hassall, 1920; Dispharynx magnilabiata (Molin, 1860) Gendre, 1920] (Nematoda, Spirurida, Acuariidae), a parasite of the roseate spoonbill Platalea ajaja L. (Ciconiiformes, Threskiornithidae) known from Brazil, France (bird in captivity), Argentina and Cuba. The species is redescribed and illustrated on the basis of the type-series (from Brazil) in the Helminthological Collection of the Naturhistorisches Museum, Vienna. Syncuaria diacantha Petter, 1961 [= Decorataria diacantha (P.) Skryabin, Sobolev & Ivashkin, 1965], originally described from Platalea ajaja in France (bird in captivity), is recognised as a junior synonym of Decorataria magnilabiata (new synonymy). PMID:21805387

  18. Molecular phylogenetic studies on filarial parasites based on 5S ribosomal spacer sequences.

    PubMed

    Xie, H; Bain, O; Williams, S A

    1994-06-01

    This paper is the first large-scale molecular phylogenetic study on filarial parasites (family Onchocercidae) which includes 16 species of 6 genera: Brugia beaveri Ash et Little, 1962, B. buckleyi Dissanaike et Paramananthan, 1961; B. malayi (Brug, 1927) Buckley, 1960; B. pahangi (Buckley et Edeson, 1956) Buckley, 1960; B. patei (Buckley, Nelson et Heisch, 1958) Buckley, 1960; B. timori Partono et al, 1977; Wuchereria bancrofti (Cobbold, 1877) Seurat, 1921: W. kalimantani Palmieri. Purnomo, Dennis and Marwoto, 1980: Mansonella perstans (Manson, 1891) Eberhard et Orihel, 1984; loa loc, Stiles, 1905; Onchocerca volvulus (Leuckart, 1983) Railliet er Henry, 1910; O. ochengi Bwangamoi, 1969; O. gutturosa Neumann, 1910; Dirofilaria immitis (Leidy, 1856) Railliet e Henry, 1911; Acanthocheilonema viteae (Krepkogorskaya, 1933) Bain, Baker et Chabaud, 1982 and Litomosoides sigmodontis Chandler, 1931. 5S rRNA gene spacer region sequence data were collected by PCR, cloning and dideoxy sequencing. The 5S rRNA gene spacer region sequences were aligned and analyzed by maximum parsimony algorithms, distance methods and maximum likelihood methods to construct phylogenetic trees. Bootstrap analysis was used to test the robustness of the different phylogenetic reconstructions. The data indicated that 5S spacer region sequences are highly conserved within species yet differ significantly between species. Spliced leader sequences were observed in all of the 5S rDNA spacers with no sequence variation, although flanking region sequence and length heterogeneity was observed even within species. All of the various tree-building methods gave very similar results. This study identified four clades which are strongly supported by bootstrap analysis the Brugia clade; the Wuchereria clade; the Brugia-Wuchereria clade and the Onchocerca clade. The analyses indicated that L. sigmodontis and A. viteae may be the most primitive among the 16 species studied. The data did not show any close

  19. The efficacy and plasma profiles of abamectin plus levamisole combination anthelmintics administered as oral and pour-on formulations to cattle.

    PubMed

    Leathwick, D M; Miller, C M; Sauermann, C W; Candy, P M; Ganesh, S; Fraser, K; Waghorn, T S

    2016-08-30

    In phase I, faecal egg count reduction tests (FECRT) were conducted on six commercial cattle farms to compare the performance of two pour-on and one oral combination anthelmintic. Groups of 12-15 calves were sampled for faecal nematode egg count (FEC) before treatment with either abamectin oral, levamisole oral, an abamectin+levamisole oral combination or one of two abamectin+levamisole combination pour-ons. Samples were collected again 14days after treatment to calculate the percentage reduction in FEC. The proportions of infective stage larvae (L3) in faecal cultures were used to apportion egg counts to, and calculate efficacy against, the main parasite genera. Abamectin oral was effective against Ostertagia except on one farm where resistance was indicated, but had reduced efficacy against Cooperia on four farms. Levamisole oral was effective against Cooperia on all farms, but had variable efficacy against Ostertagia. The abamectin+levamisole oral was effective against both species on all farms. The abamectin+levamisole pour-ons were effective on some farms but not on others. In particular, pour-on 2 failed to achieve 95% efficacy in 45% of evaluations, 4/6 against Cooperia and 1/5 against Ostertagia. On some farms the combination pour-ons were less effective than their constituent actives administered alone as orals. In phase II, 8 groups of 6 calves, grazing parasite-free pasture, were infected with putatively ML-resistant isolates of Cooperia oncophora and Ostertagia ostertagi. Once infections were patent groups were treated with oral or pour-on formulations of abamectin alone, levamisole alone, abamectin+levamisole (two pour-ons) or remained untreated. Blood samples were collected for analysis and after 8days all calves were euthanized and abomasa and intestines recovered for worm counts. All treatments were effective against O. ostertagi and all treatments containing levamisole were effective against C. oncophora. Animals treated with the oral combination

  20. Helminth parasites of gemsbok (Oryx gazella) in the Klein Karoo.

    PubMed

    Ellis, M B; Boomker, J

    2006-12-01

    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. PMID:17283732

  1. The anthelmintic efficacy of albendazole against gastrointestinal roundworms, tapeworms, lungworms and liverflukes in sheep.

    PubMed

    van Schalkwyk, P C; Geyser, T L; Récio, M; Erasmus, F P

    1979-03-01

    Anthelmintic trials were carried out to evaluate the efficacy of albendazole against helmi of 2,5 to 3,8 mg/kg administered orally, resulted in a 98,8 to 100% reduction of adult parasites of the genera Haemonchus, Ostertagia, Trichostrongylus, Nematodirus, Gaigeria, Oesophagostomum, Chabertia, Marshallagia and Cooperia. Against the immature stages of these genera, except for Marshallagia and Cooperia, which were not tested, a dose level of 2,5 to 3,8 mg/kg was 83,9-100% effective. Albendazole at 2,5 mg/kg was 99,0% effective against adult stages of Dictyocaulus; its activity at a dose of 3,8 mg/kg against the immature stages of D. filaria was 89,3%. In sheep naturally infested with Moniezia, 100% elimination was obtained at a dose level of 2,5 mg/kg. Dose levels of 3,8 mg/kg and higher were more than 76% effective against adult Fasciola hepatica, while a dose of 4,8 mg/kg was 63% effective against adult Fasciola gigantica. PMID:551183

  2. Prevalence of internal parasites in beef cows in the United States: Results of the National Animal Health Monitoring System's (NAHMS) beef study, 2007-2008.

    PubMed

    Stromberg, Bert E; Gasbarre, Louis C; Ballweber, Lora R; Dargatz, David A; Rodriguez, Judith M; Kopral, Christine A; Zarlenga, Dante S

    2015-10-01

    During the United States Department of Agriculture (USDA) National Animal Health Monitoring System's (NAHMS) 2007-2008 beef study, 567 producers from 24 US States were offered the opportunity to collect fecal samples from weaned beef calves and have them evaluated for the presence of parasite eggs (Phase 1). Participating producers were provided with instructions and materials for sample collection. Up to 20 fresh fecal samples were collected from each of the 99 participating operations. Fresh fecal samples were submitted to one of 3 randomly assigned laboratories for evaluation. Upon arrival at the laboratories, all samples were processed for the enumeration of strongyle, Nematodirus, and Trichuris eggs using the modified Wisconsin technique. The presence or absence of coccidian oocysts and tapeworm eggs was also noted. In submissions where the strongyle eggs per gram exceeded 30, aliquots from 2 to 6 animals were pooled for DNA extraction. Extracted DNA was subjected to genus level polymerase chain reaction (PCR) identification for the presence of Ostertagia, Cooperia, Haemonchus, Oesophagostomum, and Trichostrongylus. In this study, 85.6% of the samples had strongyle type, Nematodirus, and Trichuris eggs. Among the samples evaluated, 91% had Cooperia, 79% Ostertagia, 53% Haemonchus, 38% Oesophagostomum, 18% Nematodirus, 7% Trichuris, and 3% Trichostrongylus. The prevalence of coccidia and tapeworm eggs was 59.9% and 13.7%, respectively. PMID:26424909

  3. Anthelmintic activity of albendazole against gastrointestinal nematodes in calves.

    PubMed

    Benz, G W; Ernst, J V

    1977-09-01

    Anthelmintic activities of albendazole were evaluated in a controlled experiment. Forty calves experimentally infected with gastrointestinal nematodes were allotted to 4 groups. Calves in group 1 were used as nonmedicated controls; calves in groups 2, 3, and 4 were given (by oral route) a suspension containing albendazole at dose concentrations of 2.5, 5.0, and 7.5 mg/kg of body weight on the 35th day after administration of infective nematode larvae. In groups 2, 3, and 4 calves, average overall reductions (based on geometric means) were 77.1, 93.6, and 98.1%, respectively. These reductions were highly significant (P less than 0.01) in calves given doses of 5.0 and 7.5 mg/kg, and were significant (P less than 0.05) in calves given the 2.5-mg/kg dose. Ostertagia ostertagi, Trichostrongylus axei, Cooperia onchophora, Cooperia punctata, and Oesophagostomum radiatum removals at the 5.0- and 7.5-mg/kg dose levels were all highly significant (P less than 0.01); whereas, removals of Haemonchus contortus were not significant, even at the 7.5-mg/kg dose level. PMID:921039

  4. The morphology and systematics of Rhabdochona paski Baylis, 1928 (Nematoda: Rhabdochonidae), a widespread parasite of freshwater fishes in Africa.

    PubMed

    Moravec, František; Charo-Karisa, Harrison; Jirků, Miloslav

    2013-05-01

    Nematodes of the genus Rhabdochona Railliet, 1916, identified as R. paski Baylis, 1928, were collected from the intestine of Hydrocynus forskahlii (Cuvier) (Characiformes: Alestidae), Oreochromis niloticus (Linnaeus) and Tilapia zillii (Gervais) (both Perciformes: Cichlidae) from Lake Turkana, Kenya during 2007-2009. Their morphology was studied in detail using light and scanning electron microscopy. Paratypes of R. paski and museum specimens of R. congolensis Campana-Rouget, 1961 from six other host species were examined for comparison. Based on these studies and the available literature data, Rhabdochona congolensis, R. aegyptiaca El-Nafar & Saoud, 1974 (emend.) and R. vesterae Boomker & Petter, 1993 are considered to be junior synonyms of R. paski. The occurrence of this widely distributed African nematode in many fish species belonging to different families and orders suggests that most of them are probably not definitive hosts of this parasite, but only serve as paratenic, paradefinitive or postcyclic hosts (sensu Odening, 1976). True definitive hosts of R. paski appear to be characiform species belonging to some genera (e.g., Alestes, Brycinus, Hydrocynus) of the family Alestidae. PMID:23595492

  5. A new species of Atriotaenia (Cestoda: Anoplocephalidae) from the hog-nosed skunk Conepatus chinga (Carnivora: Mephitidae) in Peru.

    PubMed

    Gomez-Puerta, Luis A; Ticona, Daniel S; Lopez-Urbina, Maria T; Gonzalez, Armando E

    2012-08-01

    Atriotaenia sanmarci n. sp. (Cestoda: Anoplocephalidae) is described as a parasite of the Andean hog-nosed skunk, Conepatus chinga (Carnivora: Mephitidae), from Cusco, Perú. The new species is primarily distinguished from related species by the distribution, and greater number, of testes, i.e., 194-223 versus 40-60 in Atriotaenia sandgroundi (Sandground, 1926) Baer, 1935, 47-73 in Atriotaenia procyonis (Chandler, 1942) Spasskii, 1951, and 21-84 in Atriotaenia incisa Railliet, 1899. Also, there are differences with respect to the larger dimensions of suckers (300-371 µm vs. 140 in A. sandgroundi, 83-134 in A. procyonis, 70-140 in A. incisa, and 155-192 in Atriotaenia hastati Vaucher, 1982) and in the cirrus pouch length (204-732 µm vs. 90 in A. sandgroundi, 200-220 in A. procyonis, 100-180 in A. incisa, and 150-205 in A. hastati). The new species differs from A. sandgroundi and A. hastati in having a larger body size (122-133 mm vs. 10.6 and 10, respectively). This cestode is the fifth species of Atriotaenia Sandground, 1926. PMID:22339059

  6. Effects of treatments with endectocide on the weight gain of grazing cattle in a warm temperate climate.

    PubMed

    Mercier, P; Steffan, P E; White, C R

    2001-09-01

    Five groups of 20 weaned beef calves were injected subcutaneously with either an ivermectin, a doramectin, an abamectin long-acting formulation, an ivermectin long-acting formulation or a saline control, at turnout and 60 and 120 days later. The animals grazed the same pasture and were sampled and weighed at turnout and 30, 60, 90, 120, 150 and 180 days later. At turnout the mean bodyweights of all the groups were similar and faecal culture showed that they had a mixed strongyle infection of Cooperia, Haemonchus, Ostertagia, Oesophagostomum and Trichostrongylus species. After 180 days, the mean bodyweight gains of each group were respectively 62.1 kg, 102.2 kg, 106.4 kg, 107.3 kg and 110.1 kg for the control, ivermectin, doramectin, ivermectin long-acting and abamectin long-acting groups. All the products significantly improved the weight gains of the cattle, and significantly reduced their faecal egg counts. PMID:11558661

  7. Efficacy of two cyclooctadepsipeptides, PF1022A and emodepside, against anthelmintic-resistant nematodes in sheep and cattle.

    PubMed

    von Samson-Himmelstjerna, G; Harder, A; Sangster, N C; Coles, G C

    2005-03-01

    Resistance against the major currently available anthelmintics has reached a critical level in many small ruminant herds world-wide, and is increasingly becoming a problem in horses and cattle. Therefore, new products with different modes of action are urgently needed. Recently, such a new class of compounds, the anthelmintically active cyclooctadepsipeptides, was described. Here, the effects of cyclooctadepsipeptides on benzimidazole-, levamisole- and ivermectin-resistant populations of Haemonchus contortus in sheep as well as an ivermectin-resistant Cooperia oncophora population in cattle were studied. Experimentally infected sheep and cattle were used. Animals were treated orally, subcutaneously, or intravenously with cyclooctadepsipeptides. The anthelmintic effects were assessed by means of fecal egg count reductions and/or worm count reductions. Both, PF1022A and emodepside were found to be fully effective against these parasite populations. These findings confirm that this new class of compounds acts by a different mode of action compared to the above-mentioned anthelmintics. PMID:15796017

  8. Efficacy of an albendazole feed formulation against bovine gastrointestinal nematodes including arrested larvae of Ostertagia ostertagi.

    PubMed

    Courtney, C H; Greiner, E C; Whitten, R D

    1986-01-01

    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, Ostertagia ostertagi, Trichostrongylus axei, Cooperia punctata, and C pectinata. There was no significant effect against arrested 4th-stage larvae of O ostertagi. Adverse effects of albendazole treatment were not observed, and the premix formulation was readily consumed by cattle. PMID:3946888

  9. Effectiveness of current anthelmintic treatment programs on reducing fecal egg counts in United States cow-calf operations

    PubMed Central

    Gasbarre, Louis C.; Ballweber, Lora R.; Stromberg, Bert E.; Dargatz, David A.; Rodriguez, Judy M.; Kopral, Christine A.; Zarlenga, Dante S.

    2015-01-01

    During the United States Department of Agriculture (USDA) National Animal Health Monitoring System’s (NAHMS) 2007–2008 beef study, producers from 24 states were offered the opportunity to evaluate their animals for internal parasites and for overall responses to treatment with anthelmintics. A lapse of 45 d was required between initial sampling and any previous treatments. Choice of anthelmintic (oral benzimidazoles, and both injectable and pour-on endectocides) was at the discretion of the producer so as not to alter the local control programs. Fresh fecal samples were collected from 20 animals, or from the entire group if less than 20, then randomly assigned to 1 of 3 participating laboratories for examination. Analyses consisted of double centrifugation flotation followed by enumeration of strongyle, Nematodirus, and Trichuris eggs (the presence of coccidian oocysts and tapeworm eggs was also noted). Where strongyle eggs per gram (epg) exceeded 30, aliquots from 2 to 6 animals were pooled for egg isolation and polymerase chain reaction (PCR) analysis for the presence of Ostertagia, Cooperia, Haemonchus, Oesophagostomum, and Trichostrongylus. Results from 72 producers (19 States) indicated that fecal egg count reductions were < 90% in 1/3 of the operations. All operations exhibiting less than a 90% reduction had used pour-on macrocyclic lactones as the anthelmintic treatment. While some of these less than expected reductions could have been the result of improper drug application, PCR analyses of the parasite populations surviving treatment, coupled with follow-up studies at a limited number of sites, indicated that less than expected reductions were most likely due to anthelmintic resistance in Cooperia spp. and possibly Haemonchus spp. PMID:26424910

  10. The epidemiology of nematode and fluke infections in cattle in the Red River Delta in Vietnam.

    PubMed

    Holland, W G; Luong, T T; Nguyen, L A; Do, T T; Vercruysse, J

    2000-11-10

    Over a period of 13 months, faecal samples were collected monthly from approximately 45 cattle over 3 months of age. Additionally, 74 calves of 1-2 months were sampled to determine the presence of Toxocara vitulorum eggs. Individual egg counts and infective strongyle larvae from pooled faecal samples were examined. Post-mortem worm counts were carried out on six groups of tracer calves (n=12) that had been kept for 4 weeks on pasture in and around the village studied. The following helminths were identified: T. vitulorum, Cooperia punctata, C. pectinata, C. oncophora, Oesophagostomum radiatum, Trichostrongylus axei, T. colubriformis, Haemonchus spp., Fasciola spp. and Paramphistomum spp. In 8% of the samples collected from young calves, individual egg counts for T. vitulorum were found indicative for pathogenic worm burdens. Strongyle egg counts and worm counts indicated that transmission is low without a distinct seasonality. In animals of 3-9 months old, a strongyle egg count peak can be demonstrated which at a higher age steadily and significantly decreased. In faecal cultures Cooperia spp. were most prominent in all age groups throughout the year with the exception of the period September-November when Haemonchus spp. and Oesophagostomum spp. were most prevalent. Fasciola spp. eggs were found in 22% of the collected faecal samples and the egg counts were low indicating that the intensity of Fasciola spp. infection is mild. Based on the present data, regular anthelmintic treatments seem not to be justified, except for a single treatment at the age of 2 weeks against toxocariosis. PMID:11035232

  11. Effectiveness of current anthelmintic treatment programs on reducing fecal egg counts in United States cow-calf operations.

    PubMed

    Gasbarre, Louis C; Ballweber, Lora R; Stromberg, Bert E; Dargatz, David A; Rodriguez, Judy M; Kopral, Christine A; Zarlenga, Dante S

    2015-10-01

    During the United States Department of Agriculture (USDA) National Animal Health Monitoring System's (NAHMS) 2007-2008 beef study, producers from 24 states were offered the opportunity to evaluate their animals for internal parasites and for overall responses to treatment with anthelmintics. A lapse of 45 d was required between initial sampling and any previous treatments. Choice of anthelmintic (oral benzimidazoles, and both injectable and pour-on endectocides) was at the discretion of the producer so as not to alter the local control programs. Fresh fecal samples were collected from 20 animals, or from the entire group if less than 20, then randomly assigned to 1 of 3 participating laboratories for examination. Analyses consisted of double centrifugation flotation followed by enumeration of strongyle, Nematodirus, and Trichuris eggs (the presence of coccidian oocysts and tapeworm eggs was also noted). Where strongyle eggs per gram (epg) exceeded 30, aliquots from 2 to 6 animals were pooled for egg isolation and polymerase chain reaction (PCR) analysis for the presence of Ostertagia, Cooperia, Haemonchus, Oesophagostomum, and Trichostrongylus. Results from 72 producers (19 States) indicated that fecal egg count reductions were < 90% in 1/3 of the operations. All operations exhibiting less than a 90% reduction had used pour-on macrocyclic lactones as the anthelmintic treatment. While some of these less than expected reductions could have been the result of improper drug application, PCR analyses of the parasite populations surviving treatment, coupled with follow-up studies at a limited number of sites, indicated that less than expected reductions were most likely due to anthelmintic resistance in Cooperia spp. and possibly Haemonchus spp. PMID:26424910

  12. Molecular survey of trichostrongyle nematodes in a Bison bison herd experiencing clinical parasitism, and effects of avermectin treatment.

    PubMed

    Eljaki, A A; Al Kappany, Y M; Grosz, D D; Smart, A J; Hildreth, M B

    2016-08-30

    North American bison (Bison bison) producers face many challenges, including the potential clinical and economics problems caused by trichostrongyle nematodes within their herds. Little is known about the prevalence, intensity, geographical distribution and clinical significance of these parasites in commercial bison herds, even from regions where bison production has become popular. This study involved a large herd of bison from eastern South Dakota that was experiencing clinical parasitism due to a temporary over-stocking problem. After documenting fecal egg counts (FECs) and trichostrongyle genera present among the 3 main age-categories (i.e. adults, yearlings, calves) of bison during this heavily infected grazing season, the effects of doramectin treatment on the different age groups was also evaluated. This is the first bison study using PCR to identify genera of trichostrongyles in fecal samples. Virtually all 103 bison fecal samples from all 3 age classes were shedding trichostrongyle eggs by the end of the season, and the mean FECs were 34 eggs/g (EPG) among the cows, 125 EPG in the yearlings, and 186 EGP among calves. Based upon this heavily-infected herd, there is evidence that the susceptibility of bison to trichostrongyles is more similar to beef cattle than to sheep. Other parasites such as Moniezia, Nematodirus, Trichuris, and coccidians were also identified in these samples. All but 3 of the 51 samples analyzed with PCR shown at least 1 trichostrongyle genera. Ostertagia was detected in 68.6% of the samples, Cooperia in 80.39%, Haemonchus in at least 73% and Trichostrongylus in 16% of the herd. Most commonly, bison were infected with combinations of Haemonchus/Ostertagia/Cooperia. After treatment with doramectin, the mean FECs dropped by 99.9% for all of the bison age classes. PMID:27523937

  13. Levels of infection of gastric nematodes in a flock of great cormorants (Phalacrocorax carbo) from Lake Biwa, Japan.

    PubMed

    El-Dakhly, Kh M; El-Nahass, E; Uni, S; Tuji, H; Sakai, H; Yanai, T

    2012-03-01

    A high prevalence (86.7%) of various species of nematodes was observed in the stomach of great cormorants living in Lake Biwa, Japan. There were varying numbers of adults belonging to two common genera, Eustrongylides Jagerskiold 1909 (Nematoda: Dioctophymatidae) and Contracaecum Railliet & Henry 1912 (Nematoda: Anisakidae). The first included common adenophorean nematodes comprising a single species, Eustrongylides tubifex and the second comprised ascaroid nematodes that contained four named species: Contracaecum rudolphii Hartwich, 1964, Contracaecum microcephalum Yamaguti, 1961, Contracaecum multipapillatum Drasche, 1882 and Contracaecum chubutensis Garbin, 2008. After the prevalence and intensity of the infection had been noted, both types of nematodes were frequently observed to penetrate the mucosa and intrude into the wall of the glandular stomach, where they caused gross haemorrhage and ulceration. The Eustrongylides sp. was predominantly found in a nodular lesion of the proventricular wall, while Contracaecum spp. were observed either free in the lumen of the proventriculus or, on occasion, deeply penetrating its wall. Of the Contracaecum spp., C. rudolphii was the most prevalent. Grossly, large numbers of nematodes were present in infected stomachs (for C. rudolphii intensity was 1-34 and 3-57 nematodes in male birds and 1-21 and 1-32 in females; for C. microcephalum 1-2 and 1 in male birds and 1-2 in females; for C. multipapillatum 2 in male cormorants and no infection in females; for C. chubutensis 1-2 and 1 in male birds and 1-5 and 1 in females and for E. tubifex 1-5 nematodes in male birds and 2-8 in females). Ulcerative inflammation and hyperaemia were the most common pathological presentations, especially in areas that had been invaded by parasites. Microscopically, varying degrees of granulomatous inflammatory reactions were seen, in addition to degenerated nematodes which appeared to have deeply penetrated mucosal surfaces and were surrounded by

  14. The ecology of Echinococcus multilocularis (Cestoda: Taeniidae) on St. Lawrence Island, Alaska. II. Helminth populations in the definitive host.

    PubMed

    Rausch, R L; Fay, F H; Williamson, F S

    1990-01-01

    The helminths of 1,579 arctic foxes from St. Lawrence Island were investigated by standard methods. The foxes, obtained mainly during the winter from fur trappers, harbored 22 species of helminths. Four of those were trematodes, viz., Maritrema afanassjewi Belopol'skaia, 1952, Orthosplanchnus pygmaeus Iurakhno, 1967, Plagiorchis elegans (Rudolphi, 1802) and Alaria marcianae (LaRue, 1917), each of which occurred in a single host. Two species of cestodes, Diphyllobothrium dendriticum (Nitzsch, 1824) and Mesocestoides kirbyi Chandler, 1940, were uncommon (in 2.7 and 1.3% of the foxes, respectively). Taenia polyacantha Leuckart, 1856 and Echinococcus multilocularis Leuckart, 1863 were present in about 80% of the foxes, and Taenia crassiceps (Zeder, 1800) in less than 10%. The specimens of Taenia spp. from the autumn-winter sample were usually destrobilate. In about 2% of the foxes, acanthocephalans of six species occurred. Four of those, of the genus Corynosoma Lühe, 1904, were common in marine mammals of the region; a fifth, Corynosoma clavatum Goss, 1940, has been reported previously only from marine birds of the Southern Hemisphere; and the sixth, Polymorphus cf. minutus (Goeze, 1782), has been found widely in waterfowl of the Northern Hemisphere. Of the nematodes, Sobolophyme baturini Petrov, 1930, Cylicospirura felineus (Chandler, 1925), and Physaloptera sp. were rare (with each in only one to three foxes). Trichinella nativa Boev et Britov, 1972 and Crenosoma vulpis (Dujardin, 1844) were uncommon (1.5 and 4%, respectively). The nematodes most often present were Toxascaris leonina (von Linstow, 1902) (89%) and Uncinaria stenocephala (Railliet, 1884) (40%). Several of the rare to uncommon helminths probably were transported to the island by foxes immigrating from the adjacent continents via the pack ice. PMID:2080830

  15. Biodiversity of trematodes in their intermediate mollusc and fish hosts in the freshwater ecosystems of Europe.

    PubMed

    Faltýnková, Anna; Sures, Bernd; Kostadinova, Aneta

    2016-03-01

    We analysed two novel databases containing 2,380 and 8,202 host-parasite-locality records for trematode parasites of molluscs and fishes, respectively, to assess the biodiversity of trematodes in their intermediate mollusc and fish hosts in the freshwater environment in Europe. The "mollusc" dataset covers large numbers of pulmonate (29 spp.), "prosobranch" (15 spp.) and bivalve (11 spp.) molluscs acting as first intermediate hosts for 171 trematode species of 89 genera and 35 families. Of these, 23 and 40 species utilise freshwater fishes as definitive and second intermediate hosts, respectively. The most frequently recorded families are the Echinostomatidae Looss, 1899, Diplostomidae Poirier, 1886 and Schistosomatidae Stilles & Hassal, 1898, and the most frequently recorded species are Diplostomum spathaceum (Rudolphi, 1819), D. pseudospathaceum Niewiadomska, 1984 and Echinoparyphium recurvatum (von Linstow, 1873). Four snail species harbour extremely rich trematode faunas: Lymnaea stagnalis (L.) (41 spp.); Planorbis planorbis (L.) (39 spp.); Radix peregra (O.F. Müller) (33 spp.); and R. ovata (Draparnaud) (31 spp.). The "fish" dataset covers 99 fish species of 63 genera and 19 families acting as second intermediate hosts for 66 species of 33 genera and nine families. The most frequently recorded families are the Diplostomidae Poirier, 1886, Strigeidae Railliet, 1919 and Bucephalidae Poche, 1907, and the most frequently recorded species are Diplostomum spathaceum (Rudolphi, 1819), Tylodelphys clavata (von Nordmann, 1832) and Posthodiplostomum cuticola (von Nordmann, 1832). Four cyprinid fishes exhibit the highest species richness of larval trematodes: Rutilus rutilus (L.) (41 spp.); Abramis brama (L.) (34 spp.); Blicca bjoerkna (L.) (33 spp.); and Scardinius erythrophthalmus (L.) (33 spp.). Larval stages of 50 species reported in fish are also reported in freshwater molluscs, thus indicating a relatively good knowledge of the life-cycles of fish trematodes in

  16. The zoophilic fruitfly Phortica variegata: morphology, ecology and biological niche.

    PubMed

    Otranto, D; Brianti, E; Cantacessi, C; Lia, R P; Máca, J

    2006-12-01

    Flies belonging to the subfamily Steganinae (Drosophilidae) display unusual zoophilic feeding habits at the adult and/or larval stage. Phortica variegata (Fallén) feeds on tears or eye liquid around the eyes of humans and carnivores. When feeding it is a potential vector of Thelazia callipaeda (Railliet and Henry) eyeworms. Adult and larval stages of this fly may be easily confused with other species belonging to the same genus, and little is known on the biology and ecology of P. variegata. In April-November 2005, a total of 969 P. variegata were collected in an area with a high prevalence of canine thelaziosis. The number of flies collected weekly was then related to climatic and environmental parameters (e.g. temperature, relative humidity and total rainfall) recorded daily at the collection site. The highest number of Phortica were collected during July-August. The sex ratio (number of males : females) rose from approximately 0.5 during May-July, to approximately 3.0 in August and 181 during September-October. Distributional data, representing 242 sites at which P. variegata has been collected in Europe, were analysed using a desktop implementation of the genetic algorithm for rule-set prediction (GARP) to model ecological requirements across Europe, as well as in Italy. P. variegata is shown to be mainly active at 20-25 degrees C and 50-75% RH. The ecological niche model suggests with a high degree of confidence that large areas of Europe are likely to represent suitable habitat for this species, mostly concentrated in central Europe. The results reported here contribute basic knowledge on the ecology and geographical distribution of P. variegata flies, which will be fundamental to gaining a better understanding of their role as vectors of human and animal pathogens. PMID:17199746

  17. Biological control of gastrointestinal parasitic nematodes using Duddingtonia flagrans in sheep under natural conditions in Mexico.

    PubMed

    Mendoza-De Gives, Pedro; Zapata Nieto, Claudia; Hernández, Enrique Liébano; Arellano, María Eugenia López; Rodríguez, David Herrera; Garduño, Roberto González

    2006-10-01

    This investigation was aimed to evaluate the use of an oral bio-preparation containing Duddingtonia flagrans chlamydospores for the control of sheep gastrointestinal parasitic nematodes under the Mexican cold high plateau conditions. Two groups of gastrointestinal parasitic nematode naturally infected sheep, were randomly selected and located into two free-gastrointestinal nematode larvae paddocks. Group 1 received once a week a supplement containing D. flagrans chlamydospores mixed with oats and molasses. Group 2 received a similar supplement without any fungal material. After 5 months grazing animals were discarded from the experiment and two groups of free-nematode "tracer" sheep were located into the same paddocks to collect larvae from the contaminated pastures. Animals were slaughtered and necropsied and the nematodes were obtained and counted. A screening of the number of gastrointestinal nematode larvae present on the grass was performed and compared between the two grazing areas. The results showed 56% reduction in the Ostertagia (Teladorsagia) circumcincta and 94% reduction in the Nematodirus sp. population of the "tracer" sheep who grazed on the D. flagrans-treated sheep area, compared to the nematode population in animals grazed on the non-treated area. The results of the number of larvae on the grazing pastures showed a 51.1% reduction for H. contortus, and 100% for Cooperia sp. in the area with fungi. In the case of Trichostrongylus sp. no reduction was observed, when compared to the control group. PMID:17135538

  18. The parasitic fauna of the European bison (Bison bonasus) (Linnaeus, 1758) and their impact on the conservation. Part 1. The summarising list of parasites noted.

    PubMed

    Karbowiak, Grzegorz; Demiaszkiewicz, Aleksander W; Pyziel, Anna M; Wita, Irena; Moskwa, Bożena; Werszko, Joanna; Bień, Justyna; Goździk, Katarzyna; Lachowicz, Jacek; Cabaj, Władysław

    2014-09-01

    During the current century, 88 species of parasites have been recorded in Bison bonasus. These are 22 species of protozoa (Trypanosoma wrublewskii, T. theileri, Giardia sp., Sarcocystis cruzi, S. hirsuta, S. hominis, S. fusiformis, Neospora caninum, Toxoplasma gondii, Cryptosporidium sp., Eimeria cylindrica, E. subspherica, E. bovis, E. zuernii, E. canadensis, E. ellipsoidalis, E. alabamensis, E. bukidnonensis, E. auburnensis, E. pellita, E. brasiliensis, Babesia divergens), 4 trematodes species (Dicrocoelium dendriticum, Fasciola hepatica, Parafasciolopsis fasciolaemorpha, Paramphistomum cervi), 4 cestodes species (Taenia hydatigena larvae, Moniezia benedeni, M. expansa, Moniezia sp.), 43 nematodes species (Bunostomum trigonocephalum, B. phlebotomum, Chabertia ovina, Oesophagostomum radiatum, O. venulosum, Dictyocaulus filaria, D.viviparus, Nematodirella alcidis, Nematodirus europaeus, N. helvetianus, N. roscidus, N. filicollis, N. spathiger, Cooperia oncophora, C. pectinata, C. punctata, C. surnabada, Haemonchus contortus, Mazamastrongylus dagestanicus, Ostertagia lyrata, O. ostertagi, O. antipini, O. leptospicularis, O. kolchida, O. circumcincta, O. trifurcata, Spiculopteragia boehmi, S. mathevossiani, S. asymmetrica, Trichostrongylus axei, T. askivali, T. capricola, T. vitrinus, Ashworthius sidemi, Onchocerca lienalis, O. gutturosa, Setaria labiatopapillosa, Gongylonema pulchrum, Thelazia gulosa, T. skrjabini, T. rhodesi, Aonchotheca bilobata, Trichuris ovis), 7 mites (Demodex bisonianus, D. bovis, Demodex sp., Chorioptes bovis, Psoroptes equi, P. ovis, Sarcoptes scabiei), 4 Ixodidae ticks (Ixodes ricinus, I. persulcatus, I. hexagonus, Dermacentor reticulatus), 1 Mallophaga species (Bisonicola sedecimdecembrii), 1 Anoplura (Haematopinus eurysternus), and 2 Hippoboscidae flies (Lipoptena cervi, Melophagus ovinus). There are few monoxenous parasites, many typical for cattle and many newly acquired from Cervidae. PMID:25119348

  19. Efficacy of doramectin in the prevention of gastrointestinal nematode infections in grazing cattle.

    PubMed

    Vercruysse, J; Dorny, P; Hong, C; Harris, T J; Hammet, N C; Smith, D G; Weatherley, A J

    1993-07-01

    Two studies were performed to investigate the efficacy of doramectin in the prevention of infection with Ostertagia ostertagi and Cooperia oncophora in grazing calves. In each study, 24 parasite-naive calves were randomly allotted to two equal groups and treated with either doramectin at 200 micrograms kg-1 or saline prior to mid-season turnout (Day 0) onto contaminated pasture. Faecal egg counts were carried out twice weekly from 15 to 64 days after turnout and the cumulative faecal egg count was calculated for each group of calves. In the doramectin-treated animals, eggs first appeared in the faeces 19 days and 22 days later than in controls for Studies 1 and 2, respectively. Mean cumulative faecal egg counts over the 64 days were reduced in the doramectin-treated groups by 71% and 87% for Studies 1 and 2, respectively (P < 0.01). The potential utility of injectable doramectin in the seasonal control of gastrointestinal nematode infestations in relation to these findings is discussed. PMID:8236739

  20. Impact of chemical structure of flavanol monomers and condensed tannins on in vitro anthelmintic activity against bovine nematodes.

    PubMed

    Desrues, Olivier; Fryganas, Christos; Ropiak, Honorata M; Mueller-Harvey, Irene; Enemark, Heidi L; Thamsborg, Stig M

    2016-04-01

    Plants containing condensed tannins (CT) may have potential to control gastrointestinal nematodes (GIN) of cattle. The aim was to investigate the anthelmintic activities of four flavan-3-ols, two galloyl derivatives and 14 purified CT fractions, and to define which structural features of CT determine the anti-parasitic effects against the main cattle nematodes. We used in vitro tests targeting L1 larvae (feeding inhibition assay) and adults (motility assay) of Ostertagia ostertagi and Cooperia oncophora. In the larval feeding inhibition assay, O. ostertagi L1 were significantly more susceptible to all CT fractions than C. oncophora L1. The mean degree of polymerization of CT (i.e. average size) was the most important structural parameter: large CT reduced larval feeding more than small CT. The flavan-3-ols of prodelphinidin (PD)-type tannins had a stronger negative influence on parasite activity than the stereochemistry, i.e. cis- vs trans-configurations, or the presence of a gallate group. In contrast, for C. oncophora high reductions in the motility of larvae and adult worms were strongly related with a higher percentage of PDs within the CT fractions while there was no effect of size. Overall, the size and the percentage of PDs within CT seemed to be the most important parameters that influence anti-parasitic activity. PMID:26888630

  1. Faecal egg output, contamination of pastures and serum pepsinogen concentrations in heifers with natural gastrointestinal nematode infections in north-west Spain.

    PubMed

    Mezo-Menéndez, M; Díez-Baños, P; Morrondo-Pelayo, P; Díez-Baños, N

    1995-03-01

    In 1988, 1989 and 1990 second year grazing heifers, naturally infected with gastrointestinal nematodes, were separated into two groups, one of which was treated orally with albendazole. In 1988 and 1989 treatment was administered immediately after parturition (February), and in 1990 during the last term of pregnancy (December). Both treated and control animals were grazed on separate plots in a rotational system. Maximum faecal egg counts were observed around parturition, except in 1990, when treatment was given at the end of gestation. The main genera identified were Cooperia, Trichostrongylus, Ostertagia and Oesophagostomum. The number of Ostertagia larvae in the treated groups increased from 1989 to 1990, while the others decreased. Pasture contamination with third stage larvae (L3) was lower on the plots grazed by treated heifers. Maximum numbers of L3 were found in autumn, at the end of winter, and at the beginning of spring. Mean serum pepsinogen concentrations were significantly higher in the untreated groups. This concurs with the pattern for L3 on pasture. The trial shows that if a single treatment against gastrointestinal nematodes is carried out, and the animals remain on contaminated pastures, the parasitic load tends to level out after 4-5 months under favourable climatic conditions. However, the percentages of nematode genera occurring in the new populations may differ from those in the original infection. PMID:7622791

  2. Gastrointestinal nematode infection in small ruminants in Ethiopia: A systematic review and meta-analysis.

    PubMed

    Asmare, Kassahun; Sheferaw, Desie; Aragaw, Kassaye; Abera, Mesele; Sibhat, Berhanu; Haile, Aynalem; Kiara, Henry; Szonyi, Barbara; Skjerve, Eystein; Wieland, Barbara

    2016-08-01

    Gastrointestinal (GI) nematode infections are a major health challenge affecting productive and reproductive performance of sheep and goats in Ethiopia. However, there is no comprehensive summary on the occurrence and distribution of the infection at national level. This systematic review provides pooled prevalence estimates and assesses potential predictors of the nematode infections in small ruminants, i.e. helpful in planning interventions or control strategies. The review used 50 animal level datasets retrieved from 24 manuscripts. The studies used data collected from 9407 sheep and 3478 goats. A meta-analytical approach was employed to analyze Effect size (ES). The reported GI nematodes represented eleven genera affecting sheep and goats including: Haemonchus, Trichostrongylus, Teladorsagia/Ostertagia, Strongyloides, Bunostomum, Nematodirus, Chabertia, Trichuris, Cooperia, Skrjabinema and Oesophagostomum. The GI nematodes pooled prevalence estimate in the random effect model was 75.8% (95% CI: 69.6, 80.8). The subgroup analysis revealed significant (p<0.05) differences in the prevalence between different regions and type of diagnostic methods used. 'Postmortem technique' and 'eastern part of the country' were associated with higher GI nematode prevalence and accounted for 68.1% of the between studies heterogeneity. In light of the high parasitic prevalence in all agro-ecologies, the need for strategic intervention is recommended. Meanwhile, data need to be generated for some of the regions where dependable survey reports are lacking. PMID:27154584

  3. Anthelmintics for cattle.

    PubMed

    Prichard, R K

    1986-07-01

    A number of anthelmintics are available for the control of gastrointestinal nematodes in cattle. In North America, O. ostertagi, Cooperia spp., lung worm, and F. hepatica probably cause the greatest losses in production. The older anthelmintics are often deficient in their action against some of these parasites. Recently, the Paratect morantel tartrate slow-release bolus has provided a mechanism for the prevention of infections with gastrointestinal nematodes and lung worm, to some extent, and this has been shown to produce considerable economic benefits. Fenbendazole removes arrested O. ostertagi larvae; thus, its availability is an important step in the prevention of type-2 ostertagiasis. It also has a very broad spectrum of activity that includes most other nematodes and tapeworms and is a very safe anthelmintic. Ivermectin is highly effective against almost all cattle nematodes and also has great value for the control of arthropod ectoparasites. In addition, it and levamisole are the only anti-nematode drugs that can be administered to cattle by injection. Clorsulon is a new, safe anthelmintic that provides good control of liver fluke and, thus, fills a gap in the control of helminths of cattle in North America. The efficient use of anthelmintics in association with management based on a knowledge of parasite epidemiology can ensure that cattle do not rapidly become re-infected. In this way, the benefits from the use of anthelmintics can be very considerable and far greater than the costs of control. PMID:3488116

  4. Differences in susceptibility to gastrointestinal nematode infection between Angus and Brangus cattle in south Louisiana.

    PubMed

    Peña, M T; Miller, J E; Wyatt, W; Kearney, M T

    2000-03-28

    Breed susceptibility to nematode infection was evaluated in Angus (Bos taurus) and Brangus (B. indicus crossbreed) cattle. A cow-calf herd and a yearling replacement heifer herd were monitored during one grazing season. Calves were born in March and were weaned in October. Individual rectal fecal samples were collected monthly from the two herds and processed for fecal egg counts (FEC) and coprocultures. Cow and calf FEC increased from April, reaching maximum values during the summer. Angus cows and calves had significantly (p<0.05) greater FEC than Brangus cows and calves, and Haemonchus and Cooperia were the predominant genera. Replacement heifer FEC showed a similar pattern with maximum levels during late summer/fall, and Haemonchus was the predominant genus. No significant differences were seen between breeds, however, infection levels were consistently lower in Brangus heifers. Ostertagia was present in cows and heifers only in fall/winter, which is consistent with summer inhibition. The data suggested that cows were an important source of pasture contamination for their susceptible calves and that the Brangus breed was relatively more resistant to infection. The use of B. indicus crossbreeds may help in alleviating reliance on chemical control by reducing the rate of pasture contamination and subsequent infection losses. PMID:10729645

  5. First report of multiple anthelmintic resistance in nematodes of sheep in Colombia.

    PubMed

    Gárcia, Carlos M B; Sprenger, Lew K; Ortiz, Efraín B; Molento, Marcelo B

    2016-03-01

    This study aimed to report the presence of parasites resistant to the most used anthelmintic drugs in sheep in Colombia. Four farms (denominated farm 1, 2, 3 and 4) were selected where the animals were not treated with anthelmintics for two months before the trial. Animals with faecal egg count (FEC) above 150 and of different ages were allocated into six groups, each consisting of at least 5 animals. The drugs and dosages used were: ivermectin 1% (0.2 mg/kg), albendazole 25% (5 mg/kg), fenbendazole 10% (5 mg/kg), levamisole 10% (5 mg/kg), and moxidectin 1% (0.2 mg/kg). Anthelmintic efficacy was determined by the FEC reduction test (FECRT) with a second sampling 14 days post-treatment. The efficacy of albendazole and fenbendazole at farm 1 was above 95%, which was different from the others farms. The FECRT indicated the presence of multidrug resistance in the other farms where no tested drugs showed activity higher than 79% (albendazole: 0 to 55%, fenbendazole: 51.4 to 76.6%, ivermectin: 67.3 to 93.1%, levamisole: 0 to 78.1%, and moxidectin: 49.2 to 64.1%).Haemonchus contortus was the predominant (96%) species, followed by a small presence of Trichostrongylus sp. (3%) andCooperia sp. (1%). Therefore, we report for the first time the existence of multiple anthelmintic resistance in gastrointestinal nematodes of sheep in Colombia. PMID:26871489

  6. Use of fluorescent lectin binding to distinguish eggs of gastrointestinal nematode parasites of sheep.

    PubMed

    Umair, S; McMurtry, L W; Knight, J S; Simpson, H V

    2016-02-15

    The binding of a panel of 19 lectins to carbohydrates on the eggs of economically important nematode parasites of sheep has been assessed as the basis of a rapid test to distinguish parasite eggs, at least at the genus level. A total of six lectins can be used to identify eggs of six nematode parasites: peanut agglutinin (PNA) for Haemonchus contortus; Lens culinaris agglutinin (LCA) for Teladorsagia sp; Aleuria aurantia agglutinin (AAL) for Trichostrongylus sp; Psophocarpus tetragonolobus‑II (PTLII) for Nematodirus sp; Lotus tetragonolobus lectin (LTL) for Cooperia sp and wheat germ agglutinin (WGA) for Chabertia ovina. For WGA, LCA and LTL, weak binding was also observed to H. contortus and Teladorsagia sp, Trichostrongylus sp and C. ovina eggs, respectively. Nematode eggs in two faecal samples were identically identified by both lectin binding and PCR, except for PCR identification of the eggs of Nematodirus sp, as these did not lyse. Lectins bound best to H. contortus eggs extracted from fresh faecal samples or after storage at room temperature or 4 °C for up to 24 h, but eggs stored at -20 °C or -80 °C did not bind PNA. PMID:26827865

  7. Gastrointestinal nematodes in grazing dairy cattle from small and medium-sized farms in southern Poland.

    PubMed

    Piekarska, J; Płoneczka-Janeczko, K; Kantyka, M; Kuczaj, M; Gorczykowski, M; Janeczko, K

    2013-11-15

    This study aimed to estimate the prevalence of gastrointestinal nematodes and the intensity of infection in grazing dairy cattle from small and medium-sized farms in southern Poland. The level of antibodies against Ostertagia ostertagi in the bulk tank milk (BTM) from the animals was also assessed. Rectal fecal samples collected from 361 cows on 20 farms were examined using Willis-Schlaaf flotation and the McMaster method. BTM samples were tested for the presence of O. ostertagi antibodies using ELISA. Multiplex PCR was used to identify the third-stage larvae (L3) of gastrointestinal nematodes derived from the culture of pooled fecal samples from sampled farms. Gastrointestinal nematode eggs were found in the samples from 18 of the 20 herds with a prevalence range from 20.4 to 94.5%. The average number of eggs excreted in the feces of the herds was 200 eggs per gram (EPG). Antibodies to O. ostertagi were found in 20 of the examined herds (100%), of which 6 had optical density ratios (ODR) greater than 0.5. PCR results showed the presence of three nematode species: Ostertagia ostertagi, Cooperia oncophora and Oesophagostomum radiatum. PMID:23958284

  8. Assessment of the impact of plant species composition and drought stress on survival of strongylid third-stage larvae in a greenhouse experiment.

    PubMed

    Knapp-Lawitzke, Friederike; Küchenmeister, Frank; Küchenmeister, Kai; von Samson-Himmelstjerna, Georg; Demeler, Janina

    2014-11-01

    Grazing livestock is always exposed to infective parasite stages. Depending on the general health status of the animal, the farm management, environmental conditions and pasture exposure, the impact ranges from non-affected to almost moribund animals. The greenhouse experiment was performed to investigate how climatic changes and plant composition influence the occurrence/survival of strongylid third-stage larvae (L3) on pasture. Ten different types of plant species compositions (eight replicates for each) were inoculated with approximately 10,000 Cooperia oncophora L3. The different plant compositions can be assorted to two groups: without legume content and with legume content (52-62% legume content). Half of the replicates were watered adequately, while the other half was hold under drought stress (DS), mimicking longer dry periods. During the DS cycles, the respective containers were not watered until they reached the wilting point. Grass samples were taken 1, 4 and 6 weeks after inoculation, soil samples were taken only once after 6 weeks and all samples were examined for occurrence of L3. After the second DS cycle, the number of L3 present on herbage samples was reduced significantly. The higher the legume content of the pasture composition, the higher is the L3 occurrence on pasture. Independent of the watering scheme, the soil served as the most important reservoir with consistently higher numbers of L3 in the soil compared to herbage. PMID:25164273

  9. Morphological variability and molecular identification of Uncinaria spp. (Nematoda: Ancylostomatidae) from grizzly and black bears: new species or phenotypic plasticity?

    PubMed

    Catalano, Stefano; Lejeune, Manigandan; van Paridon, Bradley; Pagan, Christopher A; Wasmuth, James D; Tizzani, Paolo; Duignan, Pádraig J; Nadler, Steven A

    2015-04-01

    The hookworms Uncinaria rauschi Olsen, 1968 and Uncinaria yukonensis ( Wolfgang, 1956 ) were formally described from grizzly ( Ursus arctos horribilis) and black bears ( Ursus americanus ) of North America. We analyzed the intestinal tracts of 4 grizzly and 9 black bears from Alberta and British Columbia, Canada and isolated Uncinaria specimens with anatomical traits never previously documented. We applied morphological and molecular techniques to investigate the taxonomy and phylogeny of these Uncinaria parasites. The morphological analysis supported polymorphism at the vulvar region for females of both U. rauschi and U. yukonensis. The hypothesis of morphological plasticity for U. rauschi and U. yukonensis was confirmed by genetic analysis of the internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA. Two distinct genotypes were identified, differing at 5 fixed sites for ITS-1 (432 base pairs [bp]) and 7 for ITS-2 (274 bp). Morphometric data for U. rauschi revealed host-related size differences: adult U. rauschi were significantly larger in black bears than in grizzly bears. Interpretation of these results, considering the historical biogeography of North American bears, suggests a relatively recent host-switching event of U. rauschi from black bears to grizzly bears which likely occurred after the end of the Wisconsin glaciation. Phylogenetic maximum parsimony (MP) and maximum likelihood (ML) analyses of the concatenated ITS-1 and ITS-2 datasets strongly supported monophyly of U. rauschi and U. yukonensis and their close relationship with Uncinaria stenocephala (Railliet, 1884), the latter a parasite primarily of canids and felids. Relationships among species within this group, although resolved by ML, were unsupported by MP and bootstrap resampling. The clade of U. rauschi, U. yukonensis, and U. stenocephala was recovered as sister to the clade represented by Uncinaria spp. from otariid pinnipeds. These results support the absence of strict

  10. Coccidian oöcysts as type-specimens: long-term storage in aqueous potassium dichromate solution preserves DNA.

    PubMed

    Williams, R B; Thebo, P; Marshall, R N; Marshall, J A

    2010-05-01

    Preservation of the exogenous oöcyst stage of coccidian parasites (phylum Apicomplexa N.D. Levine, 1970) as type-specimens of newly described species has long been problematical. Conventional fixatives have proved unsatisfactory, and compromises such as embedding oöcysts in resin or photographing them are not entirely appropriate for various reasons. As an alternative, chilled potassium dichromate solution (normally used in the laboratory to prevent putrefaction of temporary preparations of live oöcysts) has been tested as a long-term preservative of sporulated oöcysts of Eimeria brunetti P.P. Levine, 1942, E. maxima Tyzzer, 1929, E. mitis Tyzzer, 1929, E. necatrix Johnson, 1930, E. praecox Johnson, 1930 and E. tenella (Railliet & Lucet, 1891) (suborder Eimeriorina Léger, 1911; family Eimeriidae Minchin, 1903). Oöcysts from faeces of chickens Gallus gallus (Linnaeus) were placed in 2.5% w/v aqueous potassium dichromate solution (PDS) and stored in the dark at 4 +/- 2 degrees C. After 23 years in storage, oöcysts of each species were administered orally to chickens and failed to initiate infections, indicating that the oöcysts were dead. Nevertheless, after about 24 years, DNA was still recoverable from the oöcysts, and the original species identifications made by classic parasitological methods were confirmed by polymerase chain reaction assays. Furthermore, after almost 25 years, microscopical examination revealed that the walls and internal structures remained well preserved in 83-98% of the oöcysts of the six species investigated. Hence, PDS is potentially suitable for the long-term preservation of sporulated coccidian oöcysts as type-specimens for taxonomic purposes. The samples used in this study are now in the care of the Natural History Museum, London, UK. It is recommended that they be monitored in like manner, by suitably qualified scientists, at intervals of about 5 years to assess their state of preservation and the recoverability of DNA

  11. [Ecology of Thelazia spp. in cattle and their vectors in Italy].

    PubMed

    Giangaspero, A; Traversa, D; Otranto, D

    2004-06-01

    The genus Thelazia (Spirurida, Thelaziidae) includes a cosmopolitan group of eyeworm spirurids responsible for ocular infections in domestic and wild animals and transmitted by different species of muscids. Bovine thelaziosis is caused by Thelazia rhodesi Desmarest 1828, Thelazia gulosa Railliet & Henry 1910, and Thelazia skrjabini Erschow 1928, which occur in many countries; T. gulosa and T. skrjabini have been reported mainly in the New World, while T. rhodesi is particularly common in the Old World. In Italy, T. rhodesi was reported in southern regions a long time ago and, recently, T. gulosa and T. skrjabini have been identified in autochthonous cattle first in Apulia and then in Sardinia. Thirteen species of Musca are listed as intermediate hosts of eyeworms, but only Musca autumnalis and Musca larvipara have been demonstrated to act as vectors of Thelazia in the ex-URSS, North America, ex-Czechoslovakia and more recently in Sweden. In Italy, after the reports of T. gulosa and T. skrjabini in southern regions, the intermediate hosts of bovine eyeworms were initially only suspected as the predominant secretophagous Muscidae collected from the periocular region of cattle with thelaziosis were the face flies, M. autumnalis and M. larvipara, followed by Musca osiris, Musca tempestiva and Musca domestica. The well-known constraints in the identification of immature eyeworms to species by fly dissection and also the time-consuming techniques used constitute important obstacles to epidemiological field studies (i.e. vector identification and/or role, prevalence and pattern of infection in flies, etc.). Molecular studies have recently permitted to further investigations into this area. A PCR-RFLP analysis of the ribosomal ITS-1 sequence was developed to differentiate the 3 species of Thelazia (i.e. T. gulosa, T. rhodesi and T. skrjabini) found in Italy, then a molecular epidemiological survey has recently been carried out in field conditions throughout five seasons of

  12. Anthelmintic resistance to ivermectin and moxidectin in gastrointestinal nematodes of cattle in Europe

    PubMed Central

    Geurden, Thomas; Chartier, Christophe; Fanke, Jane; di Regalbono, Antonio Frangipane; Traversa, Donato; von Samson-Himmelstjerna, Georg; Demeler, Janina; Vanimisetti, Hima Bindu; Bartram, David J.; Denwood, Matthew J.

    2015-01-01

    Anthelmintic resistance has been increasingly reported in cattle worldwide over the last decade, although reports from Europe are more limited. The objective of the present study was to evaluate the efficacy of injectable formulations of ivermectin and moxidectin at 0.2 mg per kg bodyweight against naturally acquired gastro-intestinal nematodes in cattle. A total of 753 animals on 40 farms were enrolled in Germany (12 farms), the UK (10 farms), Italy (10 farms), and France (8 farms). Animals were selected based on pre-treatment faecal egg counts and were allocated to one of the two treatment groups. Each treatment group consisted of between 7 and 10 animals. A post-treatment faecal egg count was performed 14 days (±2 days) after treatment. The observed percentage reduction was calculated for each treatment group based on the arithmetic mean faecal egg count before and after treatment. The resistance status was evaluated based on the reduction in arithmetic mean faecal egg count and both the lower and upper 95% confidence limits. A decreased efficacy was observed in half or more of the farms in Germany, France and the UK. For moxidectin, resistance was confirmed on 3 farms in France, and on 1 farm in Germany and the UK. For ivermectin, resistance was confirmed on 3 farms in the UK, and on 1 farm in Germany and France. The remaining farms with decreased efficacy were classified as having an inconclusive resistance status based on the available data. After treatment Cooperia spp. larvae were most frequently identified, though Ostertagia ostertagi was also found, in particular within the UK and Germany. The present study reports lower than expected efficacy for ivermectin and moxidectin (based on the reduction in egg excretion after treatment) on European cattle farms, with confirmed anthelmintic resistance on 12.5% of the farms. PMID:26448902

  13. Elevated temperatures and long drought periods have a negative impact on survival and fitness of strongylid third stage larvae.

    PubMed

    Knapp-Lawitzke, Friederike; von Samson-Himmelstjerna, Georg; Demeler, Janina

    2016-04-01

    In grazing cattle, infections with gastrointestinal nematodes pose some of the most important health threats and subclinical infections result in considerable production losses. While there is little doubt that climate change will affect grazing ruminants directly, mean temperature increases of ∼3°C and longer drought stress periods in summer may also influence the free-living stages of parasitic nematodes. Hostile climatic conditions reduce the number of L3s on pasture and therefore the refugium, which is expected to result in a higher selection pressure, accelerating development of resistance against anthelmintic drugs. The aim of the current experiments was to investigate the effects of drought stress and different temperature/humidity ranges over time on the survival and fitness of Cooperia oncophora L3s and their distribution in grass and soil under controlled conditions using a climate chamber. Grass containers inoculated with L3s were analysed after 1-6weeks using descriptive statistics as well as linear models. A large proportion of L3s was recovered from soil where fitness was also better preserved than on grass. Numbers and fitness of recovered L3s declined with duration in the climate chamber under both temperature profiles. However, the results of the linear models confirmed that higher temperatures (20-33°C versus 17-22.6°C) significantly impaired survival, distribution and fitness of L3s. Application of drought stress, known as another important factor, had a surprisingly smaller impact than its duration or higher temperatures. The climate chamber enabled exclusion of confounding factors and therefore accurate interpretation of the investigated climatic aspects. The obtained results highlight the relative importance of those factors, and will help to design better models for the population dynamics of L3s on pasture in the future. Additionally, the outcomes of these investigations may offer explanations regarding interdependencies of development

  14. Prevalence and risk factors associated with gastrointestinal nematode infection in goats raised in Baybay city, Leyte, Philippines

    PubMed Central

    Rupa, Ariel Paul M.; Portugaliza, Harvie P.

    2016-01-01

    Aim: Gastrointestinal parasitism is a serious constraint affecting goat production in the Philippines. This study aimed to determine the prevalence and associated risk factors of gastrointestinal nematode infection in goat-populated barangays of Baybay City, Leyte. Materials and Methods: A total of 81 households or farms were interviewed, and 450 goats were sampled for fecalysis. Fecal egg count along with egg morphological identification and coproculture for third stage larvae identification were conducted. Descriptive statistics and logistic regression analyses were carried out to determine the farm- and animal-level prevalence and risk factors. Results: Fecalysis revealed the presence of strongyle and Trichuris spp. with a farm-level prevalence of 100% and 4.94%, respectively; and animal-level prevalence of 96.22% and 4.44%, respectively. The identified strongyle genera per barangay were Haemonchus spp. (34.79%), Trichostrongylus spp. (33.29%), Oesophagostomum spp. (24.21%), Cooperia spp. (6.93%), and Chabertia spp. (0.79%). Goats older than 12 months were four times more likely to present high strongyle burden when compared to goats <6 months. With each month increase in goat’s age, the odds of acquiring strongyle infection also increased by 1.07 times. Animals kept in goat house with cemented flooring have lower odds of acquiring strongyle (odds ratio=0.12). Goats raised for leisure purposes and fed with carabao grass (Paspalum conjugatum) were 8.12 and 5.52 times more likely to acquire Trichuris, respectively. Conclusion: Most of the backyard goat raisers in Baybay City, Leyte, do not practice sound helminth control measures as shown by the high prevalence of gastrointestinal nematodes. The most relevant risk factors for gastrointestinal nematode infection were the age of the goat, type of goat house’s flooring, purpose of raising goats, and feeding practices. PMID:27536034

  15. Lymphocyte reactivity to Ostertagia ostertagi L3 antigen in type I ostertagiasis.

    PubMed

    Klesius, P H; Washburn, S M; Ciordia, H; Haynes, T B; Snider, T G

    1984-02-01

    To better understand the immune response of calves infected with Ostertagia ostertagi, studies were conducted to examine cell-mediated immune responses to L3 antigen and phytohemagglutinin (PHA) by lymphocyte reactivity assay. The L3 antigen was prepared by freeze-thawing and sonication of exsheathed O ostertagi L3. Antigen preparations contained 40 to 60 micrograms of protein/ml and no detectable endotoxin. Cell-mediated immune responses of peripheral blood lymphocytes were determined in 3 groups of 12 calves each: (i) calves given consecutive multiple dose inoculations with L3; (ii) noninfected controls. Consecutive multiple-dose-inoculated calves showed marked increases in stimulation indices (SI) to L3 antigen over the SI of naturally inoculated calves (56.5 and 25.8, respectively). Negative SI were obtained in calves of the noninoculated control group (-1.0). No significant difference (P greater than or equal to 0.05) in response to PHA was obtained between lymphocytes from calves inoculated with O ostertagi and lymphocytes obtained from noninoculated control calves. There was significant (P less than or equal to 0.01) agreement between positive SI and evidence of patent infection (development of type I ostertagiasis). Specificity of lymphocyte reactivity was determined, using lymphocytes from 4 O ostertagi- and 2 Cooperia punctata-infected calves after challenge inoculation. Positive SI to L3 antigen were obtained, using lymphocytes from either O ostertagi- or C punctata-infected calves, indicating that there may be a lack of genus specificity for O ostertagi L3 antigen in lymphocyte reactivity assay. Kinetic studies of lymphocyte reactivity to L3 antigen and PHA showed that responses were briefly suppressed to both of these stimuli in prepatent calves.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6608886

  16. Endoparasites of the fallow deer (Dama dama) of the Antheringer Au in Salzburg, Austria.

    PubMed

    Rehbein, Steffen; Visser, Martin; Jekel, Ilse; Silaghi, Cornelia

    2014-04-01

    Although the annual harvest of fallow deer increased markedly in Austria in the past two decades, only little is known about the parasites of fallow deer in Austria. To add current faunistic knowledge on the endoparasites of fallow deer in the country, viscera from six adult males and one male fawn from the game preserve Antheringer Au, Salzburg, were examined in 2009-2010 using standard techniques, and spleen samples were screened for DNA of tick-borne pathogens (polymerase chain reaction). Infections with sarcocysts (Sarcocystis spp.) and gastrointestinal nematodes (range: 379-1,294 worms) were demonstrated in all deer; four and three bucks had Dictyocaulus eckerti (range: two to seven worms) and Varestrongylus sagittatus lungworms, respectively; Fasciola hepatica (9 and 18 flukes) were isolated from the liver of two bucks, and DNA of Babesia capreoli was isolated from the spleen of one buck. In addition, Eimeria sordida oocysts were identified in the faeces of the fawn that harboured also one Setaria sp., presumably Setaria altaica, in its mesentery. Fifteen species (morphs for the ostertagians) of gastrointestinal nematodes were identified: Ostertagia leptospicularis, Ostertagia drozdzi/Skrjabinagia ryjikovi, Spiculopteragia asymmetrica, Spiculopteragia boehmi/Rinadia mathevossiani, Trichostrongylus askivali, Trichostrongylus capricola, Cooperia pectinata, Nematodirus battus, Nematodirus roscidus, Capillaria bovis, Oesophagostomum sikae, Oesophagostomum venulosum and Trichuris globulosa. Two and four bucks had high individual burdens of more than 500 and more than 1,000 worms, respectively. As the nematode counts of the five bucks harvested during the mating season were associated with unusual high faecal egg counts, and four of the bucks had Dictyocaulus lungworms in addition, these findings may suggest a reduced resistance to parasites related with high levels of androgens and experience of stress during rut. PMID:24535173

  17. Anthelmintic resistance in gastrointestinal nematodes of beef cattle in the state of Rio Grande do Sul, Brazil

    PubMed Central

    Ramos, Fernanda; Portella, Luiza Pires; Rodrigues, Fernando de Souza; Reginato, Caroline Zamperete; Pötter, Luciana; Cezar, Alfredo Skrebsky; Sangioni, Luís Antônio; Vogel, Fernanda Silveira Flores

    2016-01-01

    Gastrointestinal nematodes resistant to anthelmintics have been reported in several regions of Brazil, and they may be associated with economic losses for the cattle industry. This study aimed to evaluate the resistance status of gastrointestinal nematodes from naturally infected beef cattle to several commercially available anthelmintics, as well as to test the efficacy of combinations of anthelmintics against multi-resistant gastrointestinal nematodes. Ten farms located in Rio Grande do Sul state were selected by: farmers' consent; extensive raising system; availability of calves aged from 7 to 9 months naturally infected by gastrointestinal nematodes; absence of anthelmintic treatment for 60 days before the study; and presence of 70–100 calves or more of both genders with ≥200 eggs per gram of feces (EPG) (sensitivity of 50 EPG). These calves were distributed into 10 groups (of 7–10 animals) per farm and treated with ivermectin, doramectin, eprinomectin, fenbendazole, closantel, nitroxynil, disophenol, levamisole, albendazole, or moxidectin. Feces were collected 2 days before treatment and 14 days after treatment. Additional groups of 7–10 calves were used to test six different two-drug combinations at four of the studied farms. In general terms, fenbendazole was the most effective drug, followed by levamisole, disophenol, and moxidectin. However, parasite resistance to multiple drugs was found in all herds, especially in the genera Cooperia spp., Trichostrongylus spp., and Haemonchus spp.. Some of the two-drug combinations were effective against nematode populations identified as resistant to the same compounds when used as single drugs. The most effective combinations were moxidectin + levamisole, doramectin + fenbendazole, and levamisole + closantel. In this study, parasites resistant to the main commercially available anthelmintics were found in all herds, and some combinations of two active components belonging to different chemical groups

  18. Persistent efficacy of doramectin against experimental nematode infections in calves.

    PubMed

    Weatherley, A J; Hong, C; Harris, T J; Smith, D G; Hammet, N C

    1993-07-01

    Three studies were conducted involving cattle exposed to experimental nematode infections. These studies were designed to investigate the prophylactic activity of a single subcutaneous treatment of doramectin at 200 micrograms kg-1 body weight against infections of Ostertagia ostertagi, Cooperia oncophora and Dictyocaulus viviparus. For each study, parasite-naive calves were randomly allocated to either a treated or a matched control group. One group received doramectin and the other received doramectin and the other received either no treatment or an injection of saline at 1 ml per 50 kg body weight by the subcutaneous route. Thereafter, all calves received a daily oral challenge of infective larvae of the particular parasite species on test in each study. Challenge of each pair of treatment/control groups continued for periods of 14, 21 or 28 days. An interval of 14-21 days was then allowed to permit the parasites which had established to mature, after which all animals were slaughtered and their worm burdens determined using standard techniques. Geometric mean worm burdens were calculated from the log worm counts and used to estimate percentage efficacy. Accumulated burdens of C. oncophora in doramectin-treated cattle resulting from a daily challenge infection for 14 or 21 days were reduced by 99.2% and 90.7% respectively, in comparison with those of non-treated control animals. For D. viviparus, burdens were reduced by 100% and 99.9% after a 21 or 28 day challenge, respectively. The corresponding figures for O. ostertagi were 99.9% after a 21 day challenge and 93.7% after a 28 day challenge. PMID:8236737

  19. Gastrointestinal nematodes in rotationally grazing ewes in the mountainous region of central Mexico.

    PubMed

    Acevedo-Ramírez, P M C; Quiroz-Romero, H; Cruz-Mendoza, I; Ulloa-Arvizu, R; Ibarra-Velarde, F

    2013-03-01

    The aims of this study were to determine the frequency of egg shedding (percentage of egg-positive faecal samples) and faecal egg counts (FEC) over 13 months in two different breeds of ewes, both pregnant and non-pregnant, in a mountainous region of central Mexico. Additionally, the effect of ivermectin and albendazole treatments on FEC reduction was recorded. The study also aimed to relate temperature and rainfall to FEC. The gastrointestinal nematode (GIN) third-stage larvae genera recovered from both faeces and grassland pastures in a temperate region were also assessed. Faecal samples were collected from ewes at monthly intervals for 13 months to investigate the FEC population of GIN larvae, their concentration and genera in grass samples collected from grazed and rested pastures. Egg-shedding frequency ranged from 0 to 92% and FEC from 0 to 12,000 eggs per g faeces (epg), with counts in Suffolk higher than in Dorset ewes. The identified genera were Haemonchus, Trichostrongylus, Teladorsagia, Cooperia, Oesophagostomum, Bunostomum, Nematodirus and Strongyloides. Haemonchus and Trichostrongylus were the most common genera. The number of L3 was higher in grazing lands than in those at rest. The highest FEC were recorded in the dry season due to peripartum, but the highest L3 counts were recorded in the rainy season. The coexistence of species of different geographical distributions at this site may be because there is a confluence of Nearctic and Neotropical geographic regions; thus, despite the temperate climate, tropical species can be found. Additionally, this study suggests that increasing temperatures could favour the presence of different tropical GIN species together with typical temperate-zone GIN species. PMID:22380595

  20. Dynamics of infestation of tracers lambs by gastrointestinal helminths under a traditional management system in the North of Tunisia

    PubMed Central

    Akkari, H.; Gharbi, M.; Darghouth, M.A.

    2012-01-01

    The authors present a survey of gastrointestinal helminths of sheep on permanent pastures in the extreme north region of Tunisia (Mediterranean climate). Dynamic infestation of animals has been monitored by using batches of three tracer lambs introduced each two months during 2004 and 2005. These lambs were kept in the pens of veterinary school of Sidi Thabet (Tunisia) during three months and then necropsied. Faecal and blood samples were took from tracer lambs each two months during the whole period, and from animal flock only during 2004. The main helminth genera encountered were Trichostrongylus spp., Teladorsagia spp., Strongyloides papillosus and Anoplocephalidea; occasionaly were found Nematodirus, Oesophagostomum, Chabertia, Cooperia, Trichuris and Paramphistomum. The egg count of the ewes and lambs in the flock showed two peaks. For both ewes and lambs there is a gradual increase from January with a peak in May-June. This first peak is considered to be due to acquisition of infective larvae during the rainy and cold season, as evident from the worm burdens of tracer lambs. The second peak was exclusively observed in ewes during late autumn-early winter (November-December); it has two origins: infestation by third larvae stage and the periparturient rise. The worm burdens of tracer lambs showed that there was a gradual accumulation of nematodes from September- October, reaching a peak in March-April; a very low or naught infection is reported during the dry period (July-August). Infection by Anoplocephalidea was higher during the dry season. This study is primordial for a comprehensive control programme implementation against gastrointestinal helminths. PMID:23193526

  1. Parasite control in transhumant situations.

    PubMed

    Eckert, J; Hertzberg, H

    1994-08-01

    Transhumance is defined as 'seasonal moving of livestock to regions of different climate'. It is an integral part of livestock production in many parts of the world and takes several forms including moving of livestock from lowland to mountainous pastures or from dry to humid areas. The impact of transhumance on parasite populations of livestock and on parasite control is described, mainly using examples from Europe. The epidemiology of trichostrongylidosis of cattle, mainly caused by Ostertagia ostertagi and Cooperia oncophora, is characterised by prolonged survival of overwintered infective larvae until the end of June. Cattle moved to such contaminated pastures in a transhumant grazing system are exposed to these larvae and may be protected, during the second half of the grazing season until autumn, by a late application (June/July) of an intraruminal drug-release device. Community pastures used in a transhumant system with mixed grazing of young cattle originating from various farms may enhance transmission of dictyocaulosis. Therefore, specific prophylactic measures are required. Hill sheep nematode populations may differ from those in lowland sheep in that Haemonchus contortus generally plays a minor role in hill sheep in which Ostertagia circumcincta and Nematodirus spp. predominate. Infections with Fasciola hepatica and Dicrocoelium dendriticum can be acquired on mountainous pastures by cattle, sheep and other livestock grazing in a transhumant system as intermediate hosts of these parasites may find suitable habitats in these regions. There is evidence that in the prealpine and alpine area both parasites are mainly transmitted in two-season cycles. Further examples for the impact of transhumance on parasite-host inter-relationships include cysticercosis in cattle, echinococcosis, psoroptic manage in sheep, tick-borne fever of cattle, and hypodermosis in cattle. These are described and discussed. PMID:7846845

  2. Efficacy of concomitant early summer treatment with fenbendazole and clorsulon against Fasciola hepatica and gastrointestinal nematodes in calves in Louisiana.

    PubMed

    Malone, J B; Williams, J C; Lutz, M; Fagan, N; Jacocks, M; Jones, E; Marbury, K; Willis, E

    1990-01-01

    The efficacy, safety, and compatibility of fenbendazole (FBZ) and clorsulon (CLN) were tested after oral administration of label recommended and of higher (5x) dosage rates to calves naturally infected with gastrointestinal nematodes and Fasciola hepatica. Results for 42 calves allotted to 4 treatment groups indicated a similar efficacy against mature F hepatica by FBZ (5 mg/kg of body weight) and CLN (7 mg/kg) in a combined oral suspension, compared with CLN (7 mg/kg) alone (100 vs 99% reduction). A lesser efficacy was observed against immature flukes (88.6 and 84.9% reduction, respectively). Calves given 25 mg of FBZ/kg and 35 mg of CLN/kg had nearly complete reduction of both mature (99.6%) and immature flukes (99.1%). Fasciola egg counts were reduced by greater than 99.5% in all treated groups. Against Ostertagia ostertagi, the percentage of efficacy of the combined FBZ (5 mg/kg) and CLN (7 mg/kg) treatment was 94.3% against adults and 81.3% against inhibited larvae. Efficacy against all other nematodes was 100%, except against Cooperia spp adults (98.3%) and immature Oesaphagostomum radiatum (88.0%). At 5 x dosage rates for FBZ and CLN, percentage of removal of adults and inhibited larvae of O ostertagi was 99.3 and 99.0%, respectively, and 99 to 100% for other nematodes. Results indicate that FBZ and CLN are compatible when mixed together and administered as an oral suspension to cattle and that the efficacy is similar to that of the drugs individually. On the basis of further results, we suggest that summer treatment may be superior in preventive value for gastrointestinal nematodes and F hepatica, compared with spring treatment, because of seasonal infection dynamics of the major cattle parasites in Louisiana. PMID:2301813

  3. Utilization of computer processed high definition video imaging for measuring motility of microscopic nematode stages on a quantitative scale: “The Worminator”

    PubMed Central

    Storey, Bob; Marcellino, Chris; Miller, Melissa; Maclean, Mary; Mostafa, Eman; Howell, Sue; Sakanari, Judy; Wolstenholme, Adrian; Kaplan, Ray

    2014-01-01

    A major hindrance to evaluating nematode populations for anthelmintic resistance, as well as for screening existing drugs, new compounds, or bioactive plant extracts for anthelmintic properties, is the lack of an efficient, objective, and reproducible in vitro assay that is adaptable to multiple life stages and parasite genera. To address this need we have developed the “Worminator” system, which objectively and quantitatively measures the motility of microscopic stages of parasitic nematodes. The system is built around the computer application “WormAssay”, developed at the Center for Discovery and Innovation in Parasitic Diseases at the University of California, San Francisco. WormAssay was designed to assess motility of macroscopic parasites for the purpose of high throughput screening of potential anthelmintic compounds, utilizing high definition video as an input to assess motion of adult stage (macroscopic) parasites (e.g. Brugia malayi). We adapted this assay for use with microscopic parasites by modifying the software to support a full frame analysis mode that applies the motion algorithm to the entire video frame. Thus, the motility of all parasites in a given well are recorded and measured simultaneously. Assays performed on third-stage larvae (L3) of the bovine intestinal nematode Cooperia spp., as well as microfilariae (mf) of the filarioid nematodes B. malayi and Dirofilaria immitis, yielded reproducible dose responses using the macrocyclic lactones ivermectin, doramectin, and moxidectin, as well as the nicotinic agonists, pyrantel, oxantel, morantel, and tribendimidine. This new computer based-assay is simple to use, requires minimal new investment in equipment, is robust across nematode genera and developmental stage, and does not require subjective scoring of motility by an observer. Thus, the “Worminator” provides a relatively low-cost platform for developing genera- and stage-specific assays with high efficiency and reproducibility, low

  4. In vitro effects of extracts and purified tannins of sainfoin (Onobrychis viciifolia) against two cattle nematodes.

    PubMed

    Novobilský, A; Stringano, E; Hayot Carbonero, C; Smith, L M J; Enemark, H L; Mueller-Harvey, I; Thamsborg, S M

    2013-09-23

    Sainfoin (Onobrychis viciifolia) is a condensed tannin (CT)-containing legume and has anthelmintic potential against gastrointestinal nematodes of ruminants. This study investigated in vitro effects of acetone/water extracts and derived CT fractions from different types of sainfoin (i.e. accessions) against larvae of Cooperia oncophora and Ostertagia ostertagi by applying the larval feeding inhibition assay (LFIA). Seven sainfoin accessions were extracted and tested with L1 larvae at 10 and 40 μg extract/ml. In addition, CT in extracts from 4 accessions were fractionated according to polymer size and tested by LFIA at two concentrations (2 and 10 μg CT fraction/ml). All sainfoin extracts caused significant inhibition of L1-feeding of both C. oncophora and O. ostertagi with varying intensity compared to the control (phosphate buffered saline). For both nematode species the in vitro effect was positively correlated with CT content in the extracts, but not with any of the structural CT parameters. In contrast, the 16 CT fractions revealed significant correlations between in vitro effect and CT content, polymer size (mean degree of polymerisation, mDP) and monomeric composition (prodelphinidin percentage, % PD). These differences between crude extracts and purified fractions may stem from the fact that extracts contain complex CT mixtures, which may mask and thus suppress CT structural effects. This study provides the first indication that, apart from CT and % PD content, polymer size also contributes to anthelmintic activity of CTs. The results, therefore, suggest that the inter-accession variability in CT content and composition needs to be taken into account in future plant breeding programmes which seek to enhance the anthelmintic properties of sainfoin. PMID:23639199

  5. Efficacy and productive performance of moxidectin in feedlot calves infected with nematodes resistant to ivermectin.

    PubMed

    Fazzio, L E; Streitenberger, N; Galvan, W R; Sánchez, R O; Gimeno, E J; Sanabria, R E F

    2016-06-15

    Anthelmintic resistance (AR) of gastrointestinal nematodes to macrocyclic lactones is an increasingly common worldwide phenomenon limiting cattle production. This has motivated the search for alternatives, such as new active compounds, added drug synergisms, different doses, and alternate administration routes. The aim of this study was the assessment of moxidectin (MXD) performance in feedlot calves with a history of AR to ivermectin (IVM). Crossbred female calves aged 6-7 months and weighing 163kg (SD=34kg) were divided into 3 groups of 35 animals each. They were assigned to the following antiparasitic treatment groups: IVM group (0.2mg/kg IVM); MXD group (0.2mg/kg MXD), and ricobendazole+levamisole (RBZ+LEV) group (7.5mg/kg RBZ+8mg/kg LEV). On days 0, 26, and 47, fecal samples were taken and the weight of each animal was registered. Anthelmintic efficacy (by fecal egg count reduction), total weight gain (TWG) and average daily weight gain (AWG) were compared between the groups. A mixed SAS procedure was used for statistical analysis. Fecal egg count reduction 26 days post-treatment (PT) was calculated at 28% for the IVM group, 85% for the MXD group, and 99% for the RBZ+LEV group. AWGs (Standard Error) of 1.095g (56), 1.264g (49), and 1.340g (52) were registered for the IVM, MXD, and RBZ+LEV groups, respectively (p<0.05). Coprocultures revealed that MXD more effectively reduced Haemonchus spp. and Cooperia spp. egg counts than IVM. This resulted in higher AWGs and TWGs for this group; similar results were seen for the RBZ+LEV group as well. In this study, animals treated with MXD gained about 160 more g/day than animals treated with IVM. This represents a gain of 16 USD per animal over the 47 day trial. PMID:27198772

  6. Anthelmintic effects of forage chicory (Cichorium intybus) against gastrointestinal nematode parasites in experimentally infected cattle.

    PubMed

    Peña-Espinoza, Miguel; Thamsborg, Stig M; Desrues, Olivier; Hansen, Tina V A; Enemark, Heidi L

    2016-09-01

    Two experiments studied the effects of dietary chicory against gastrointestinal nematodes in cattle. In Experiment (Exp.) 1, stabled calves were fed chicory silage (CHI1; n = 9) or ryegrass/clover hay (CTL1; n = 6) with balanced protein/energy intakes between groups. After 16 days, all calves received 10 000 Ostertagia ostertagi and 66 000 Cooperia oncophora third-stage larvae (L3) [day (D) 0 post-infection (p.i.)]. In Exp. 2, calves were assigned to pure chicory (CHI2; n=10) or ryegrass/clover (CTL2; n = 10) pastures. After 7 days, animals received 20 000 O. ostertagi L3/calf (D0 p.i.) and were moved regularly preventing pasture-borne infections. Due to poor regrowth of the chicory pasture, CHI2 was supplemented with chicory silage. At D40 p.i. (Exp. 1) and D35 p.i. (Exp. 2) calves were slaughtered for worm recovery. In Exp.1, fecal egg counts (FEC) were similar between groups. However, O. ostertagi counts were significantly reduced in CHI1 by 60% (geometric mean; P < 0·01), whereas C. oncophora burdens were unaffected (P = 0·12). In Exp. 2, FEC were markedly lowered in CHI2 from D22 p.i onwards (P < 0·01). Ostertagia ostertagi adult burdens were significantly reduced in CHI2 by 66% (P < 0·001). Sesquiterpene lactones were identified only in chicory (fresh/silage). Chicory shows promise as an anti-Ostertagia feed for cattle and further studies should investigate its on-farm use. PMID:27173405

  7. Low-dosage phenothiazine in the prophylaxis of trichostrongylid infection in calves.

    PubMed

    Downey, N E; O'Shea, J

    1984-10-01

    Phenothiazine (PTZ) given indoors to calves artificially infected with Ostertagia ostertagi and Cooperia oncophora showed ovicidal activities of 100, 93, 98 and 85% respectively at daily doses of 9, 8, 7 and 6 mg kg-1. In a grazing study, one group of calves was treated with PTZ via the drinking water, using a "Profel" liquid dispenser. The dispenser was calibrated to add PTZ to the water at a daily dose of 7 mg kg-1, but in practice the dose far exceeded this amount. A dose of 7 mg kg-1 day-1 was given manually to a second group and a third group acted as control, receiving no PTZ. PTZ-induced photosensitivity was widespread in the first group due to over-dosage of medicament by the dispenser and was suspected in one calf in the manually dosed group. PTZ in both treated groups showed marked ovicidal activity and, apparently as a result of this, caused striking reductions in trichostrongylid infection on the pasture and in the calves as evidenced by pasture larval counts, calves' egg counts, pepsinogen levels and live weight gains. Necropsy worm counts showed that the PTZ medication prevented heavy infection by arrested as well as by adult Ostertagia. The reduced infection on the treated calves' pasture was carried over for a second grazing season. Untreated calves grazing the pasture in that season showed lower infection and improved weight gains up to mid-September compared with calves on the control pasture. These effects did not persist for the whole of the second season. PMID:6543053

  8. Anthelmintic resistance in gastrointestinal nematodes of beef cattle in the state of Rio Grande do Sul, Brazil.

    PubMed

    Ramos, Fernanda; Portella, Luiza Pires; Rodrigues, Fernando de Souza; Reginato, Caroline Zamperete; Pötter, Luciana; Cezar, Alfredo Skrebsky; Sangioni, Luís Antônio; Vogel, Fernanda Silveira Flores

    2016-04-01

    Gastrointestinal nematodes resistant to anthelmintics have been reported in several regions of Brazil, and they may be associated with economic losses for the cattle industry. This study aimed to evaluate the resistance status of gastrointestinal nematodes from naturally infected beef cattle to several commercially available anthelmintics, as well as to test the efficacy of combinations of anthelmintics against multi-resistant gastrointestinal nematodes. Ten farms located in Rio Grande do Sul state were selected by: farmers' consent; extensive raising system; availability of calves aged from 7 to 9 months naturally infected by gastrointestinal nematodes; absence of anthelmintic treatment for 60 days before the study; and presence of 70-100 calves or more of both genders with ≥ 200 eggs per gram of feces (EPG) (sensitivity of 50 EPG). These calves were distributed into 10 groups (of 7-10 animals) per farm and treated with ivermectin, doramectin, eprinomectin, fenbendazole, closantel, nitroxynil, disophenol, levamisole, albendazole, or moxidectin. Feces were collected 2 days before treatment and 14 days after treatment. Additional groups of 7-10 calves were used to test six different two-drug combinations at four of the studied farms. In general terms, fenbendazole was the most effective drug, followed by levamisole, disophenol, and moxidectin. However, parasite resistance to multiple drugs was found in all herds, especially in the genera Cooperia spp., Trichostrongylus spp., and Haemonchus spp.. Some of the two-drug combinations were effective against nematode populations identified as resistant to the same compounds when used as single drugs. The most effective combinations were moxidectin + levamisole, doramectin + fenbendazole, and levamisole + closantel. In this study, parasites resistant to the main commercially available anthelmintics were found in all herds, and some combinations of two active components belonging to different chemical groups were effective

  9. Sensitivity and efficiency of selected coproscopical methods-sedimentation, combined zinc sulfate sedimentation-flotation, and McMaster method.

    PubMed

    Becker, Ann-Christin; Kraemer, Amelie; Epe, Christian; Strube, Christina

    2016-07-01

    Coproscopical methods used in veterinary-parasitological diagnostics were validated according to their sensitivity (Se) and egg recovery rate [efficiency (Ef)]. Validation of the combined sedimentation-flotation method and the modified McMaster method was performed by using feces spiked with eggs of Ancylostoma caninum, Uncinaria stenocephala, Cooperia oncophora, cyathostomins, Ascaris suum, Toxascaris leonina, Toxocara canis, Trichuris vulpis, Moniezia expansa, and Anoplocephala perfoliata. For validation of the sedimentation method, Fasciola hepatica eggs were used. With the combined sedimentation-flotation method using ZnSO4 as flotation medium [specific gravity (SG) 1.30], 5 g fecal samples of all tested parasite species (concentration levels 1, 5, 10, 20, 40, 60, and 80 epg) were reproducibly detected "positive" (100 % Se) as of 80 epg. The Ef of the combined sedimentation-flotation method, defined as percentage of rediscovered eggs, revealed clear differences between parasites and showed the highest value for cyathostomins and the lowest for U. stenocephala and T. leonina eggs. The average Ef for all parasite species at 80 epg was 1.50 %. With the McMaster method (concentration levels 1, 30, 50, 80, 100, 500, and 1000 epg), all tested parasite species were detected reliably positive as of 500 epg with a mean Ef of 46.4 %. When evaluating the sedimentation method (concentration levels 1, 5, 10, 15, 20, 25, and 30 epg), F. hepatica eggs were reproducibly found in 5 g fecal samples as of 20 epg with 20.0 % Ef. The result that the combined zinc sulfate sedimentation-flotation method (SG 1.30) as flotation medium provides diagnostic certainty only as of 80 epg has to be considered at preventing zoonoses. If pet owners wish to prevent any zoonotic infection ("zero tolerance"), a monthly anthelminthic treatment should be advised instead of monthly fecal examinations. PMID:26997342

  10. Endectocide activity of a pour-on formulation containing 1.5 per cent ivermectin +0.5 per cent abamectin in cattle

    PubMed Central

    Silva, Heloisa Cristina; Prette, Nancy; Lopes, Welber Daniel Zanetti; Sakamoto, Cláudio Alessandro M; Buzzulini, Carolina; dos Santos, Thais Rabelo; Cruz, Breno Cayeiro; Teixeira, Weslen F Pires; Felippelli, Gustavo; Carvalho, Rafael Silveira; Maciel, Willian Giquelin; Soares, Vando Edésio; da Costa, Alvimar José

    2015-01-01

    The present work aimed to evaluate, through ten different studies, the therapeutic efficacy of a new pour-on formulation, containing 1.5 per cent ivermectin +0.5 per cent abamectin, against parasites of cattle. Results obtained on trials against Rhipicephalus (Boophilus) microplus showed that the pour-on combination of 1.5 per cent ivermectin +0.5 per cent abamectin obtained superior efficacy indexes against this ectoparasite, when compared with formulations containing 0.5 per cent ivermectin, 1 per cent ivermectin and the combination of 1 per cent abamectin +20 per cent levamisole. The results of efficacy of the ivermectin+abamectin and the 0.5 per cent ivermectin against Haematobia irritans were similar. Against Cochliomyia hominivorax larvae, all pour-on formulations tested (1.5 per cent ivermectin +0.5 per cent abamectin, 0.5 per cent ivermectin and 0.5 per cent abamectin), as well as 1 per cent doramectin administered subcutaneously, were considered ineffective. Cattle medicated with 1.5 per cent ivermectin +0.5 per cent abamectin, pour-on, remained free from parasitism by Dermatobia hominis larvae during 42 days (96 per cent efficacy), while values superior to 90 per cent were obtained by 0.5 per cent ivermectin (92 per cent) and 0.5 per cent abamectin (93 per cent) until the 42nd and 35th days post treatment, respectively. Against Haemonchus placei and Oesophagostomum radiatum, the pour-on of ivermectin+abamectin showed better efficacy than the 0.5 per cent ivermectin and 0.5 per cent abamectin. As to Cooperia punctata, there was no difference regarding efficacy results obtained by the avermectins combination and abamectin. The pour-on combination of 1.5 per cent ivermectin +0.5 per cent abamectin obtained high efficacy against R. (B.) microplus, D. hominis and some species of cattle gastrointestinal helminths when compared with formulations of 0.5 per cent ivermectin and 0.5 per cent abamectin administered through the same route. PMID:26392893

  11. Anthelmintic resistance in cattle nematodes in the US.

    PubMed

    Gasbarre, Louis C

    2014-07-30

    The first documented case of macrocyclic lactone resistance in gastrointestinal (GI) nematodes of cattle was seen in the US approximately 10 years ago. Since that time the increase incidence of anthelmintic resistance has continued at an alarming rate. Currently parasites of the genera Cooperia and/or Haemonchus resistant to generic or brand-name macrocyclic lactones have be demonstrated in more than half of all operations examined. Both of these parasite genera are capable of causing economic losses by decreasing food intake and subsequently animal productivity. Currently, there are no easy and quick means to detect anthelmintic resistant GI nematodes. Definitive identification requires killing of cattle. The most commonly used field detection method is the fecal egg count reduction test (FECRT). This method can be adapted for use as a screening agent for Veterinarians and producers to identify less than desired clearance of the parasites after anthelmintic treatment. Further studies can then define the reasons for persistence of the egg counts. The appearance of anthelmintic resistance is largely due to the development of very effective nematode control programs that have significantly improved the productivity of the US cattle industry, but at the same time has placed a high level of selective pressure on the parasite genome. The challenges ahead include the development of programs that control the anthelmintic resistant nematodes but at the same time result in more sustainable parasite control. The goal is to maintain high levels of productivity but to exert less selective pressures on the parasites. One of the most effective means to slow the development of drug resistance is through the simultaneous use of multiple classes of anthelmintics, each of which has a different mode of action. Reduction of the selective pressure on the parasites can be attained through a more targeted approach to drug treatments where the producer's needs are met by selective

  12. A cross-sectional survey of gastrointestinal parasites with dispersal stages in feces from Costa Rican dairy calves.

    PubMed

    Jiménez, A E; Fernández, A; Alfaro, R; Dolz, G; Vargas, B; Epe, C; Schnieder, T

    2010-10-29

    A cross-sectional study was carried out to determine the prevalence of gastrointestinal parasites and lungworm nematodes in dairy calves from five different ecoclimatic areas of Costa Rica. Also intensity of infection of nematodes was determined. In order to describe management practices and anthelmintic control, a questionnaire was applied in 73 farms. The influence of area, farm, host (breed, age) and ecological factors (low and high rainfall period) upon eggs per gram feces (epg) of gastrointestinal nematodes (GIN) and first larval stage counts (L1) of Dictyocaulus viviparus were investigated. Furthermore, association of host, ecological and management risk factors to the prevalence of gastrointestinal parasites and D. viviparus were analyzed. The most prevalent GIN, cestodes and protozoan identified in dairy farms were similar in all areas studied. Strongylidae was the most prevalent parasite group detected, represented mainly by Haemonchus spp. and Cooperia spp., whereas Ostertagia spp. and Mecistocirrus digitatus were barely found. The most prevalent protozoan was Eimeria spp. The questionnaire applied to producers revealed the following management practices: weaning age of calves 1-4 months (52.1%), semi-confinement of calves upon 5-8 months of age (41.1%), number of paddocks used for calves <10 (57.5%), first deworming of calves at ages ≥15 days (74.70%) and deworming of calves at intervals >60 days (52.1%). Anthelmintic products were changed in 56.1% of the farms at intervals between 13 and 24 months. Although 91.8% of the farms had veterinary assistance, the majority performed parasite control regimes according to the criteria of the producers (66.7%). Common practices were the dispersion of animal feces on the pastures (64.4%) and use of disinfectant in the milking room (63.4%). The analyses of variance showed significant influence (p<0.05) of age, rainfall period, interaction of rainfall period on area (rainfall period×area) and nested effect of farm

  13. Endectocide activity of a new long-action formulation containing 2.25% ivermectin+1.25% abamectin in cattle.

    PubMed

    Borges, F A; Silva, H C; Buzzulini, C; Soares, V E; Santos, E; Oliveira, G P; Costa, A J

    2008-08-17

    The present work aimed to evaluate the endectocide activity of a new injectable long-action formulation, containing ivermectin (IVM) and abamectin (ABA). In each one of the four experiments performed, the following groups were formed: group I: 2.25% IVM (450 microg/kg)+1.25% ABA (250 microg/kg), group II: 3.15% IVM (630 microg/kg) and group III: control. Eighteen bovine naturally infected by gastrointestinal nematoda were selected for anthelmintic evaluation and necropsied on posttreatment day (PTD) 14 to estimate the total parasitic burden. For the Rhipicephalus (Boophilus) microplus field trial, 30 bovine were selected by means of counts of semi-engorged R. (B.) microplus and the therapeutic and residual efficacy evaluated by tick counts on PTDs 1, 3, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84 and 91. In the stall test, 15 calves were artificially infested with 5000 R. (B.) microplus (Mozzo strain) larvae three times a week and daily collections of all the engorged female ticks detached from each calf were performed until the PTD 80. Forty bovine naturally infected with Dermatobia hominis larvae were selected and the number of larvae was counted by visual and tactile inspection on PTDs 3, 7, 14, 28, 35, 49, 63, 77, 91 and 105. In this trial, a formulation containing 1% doramectin (200 microg/kg) was also used. IVM+ABA formulation and 3.15% IVM eliminated four of the eight species of nematode identified. The anthelmintic efficacy of the avermectins association against Haemonchus placei, Cooperia spatulata and C. punctata was 89.64%, 98.84% and 97.69%, while 3.15% IVM achieved 30.98%, 84.79% and 75.56%, respectively. The two formulations evaluated showed reduced acaricide action on the PTD 1 and 3, reaching high efficacy percentages from PTD 14 onward. The IVM+ABA showed efficacy above 95% in the period between PTDs 21 and 49. In the stall test, it observed no difference (P>0.05) between the two formulations regarding the R. (B.) microplus counts during the

  14. SLO-1-Channels of Parasitic Nematodes Reconstitute Locomotor Behaviour and Emodepside Sensitivity in Caenorhabditis elegans slo-1 Loss of Function Mutants

    PubMed Central

    Schniederjans, Monika; Miltsch, Sandra M.; Krücken, Jürgen; Guest, Marcus; Holden-Dye, Lindy; Harder, Achim; von Samson-Himmelstjerna, Georg

    2011-01-01

    The calcium-gated potassium channel SLO-1 in Caenorhabditis elegans was recently identified as key component for action of emodepside, a new anthelmintic drug with broad spectrum activity. In this study we identified orthologues of slo-1 in Ancylostoma caninum, Cooperia oncophora, and Haemonchus contortus, all important parasitic nematodes in veterinary medicine. Furthermore, functional analyses of these slo-1 orthologues were performed using heterologous expression in C. elegans. We expressed A. caninum and C. oncophora slo-1 in the emodepside-resistant genetic background of the slo-1 loss-of-function mutant NM1968 slo-1(js379). Transformants expressing A. caninum slo-1 from C. elegans slo-1 promoter were highly susceptible (compared to the fully emodepside-resistant slo-1(js379)) and showed no significant difference in their emodepside susceptibility compared to wild-type C. elegans (p = 0.831). Therefore, the SLO-1 channels of A. caninum and C. elegans appear to be completely functionally interchangeable in terms of emodepside sensitivity. Furthermore, we tested the ability of the 5′ flanking regions of A. caninum and C. oncophora slo-1 to drive expression of SLO-1 in C. elegans and confirmed functionality of the putative promoters in this heterologous system. For all transgenic lines tested, expression of either native C. elegans slo-1 or the parasite-derived orthologue rescued emodepside sensitivity in slo-1(js379) and the locomotor phenotype of increased reversal frequency confirming the reconstitution of SLO-1 function in the locomotor circuits. A potent mammalian SLO-1 channel inhibitor, penitrem A, showed emodepside antagonising effects in A. caninum and C. elegans. The study combined the investigation of new anthelmintic targets from parasitic nematodes and experimental use of the respective target genes in C. elegans, therefore closing the gap between research approaches using model nematodes and those using target organisms. Considering the still

  15. Changes in biochemical analytes in calves infected by nematode parasites in field conditions.

    PubMed

    de Cezaro, Marcela C; Tvarijonaviciute, Asta; Tecles, Fernando; Céron, José J; Eckersall, David P; Ferreira, João C P; Schmidt, Elizabeth M S

    2016-03-30

    Parasitic infections caused by nematodes are a major problem in bovines that resulting in losses in animal health and production. Thus, the aim of this study was to evaluate alterations in selected serum biochemical analytes in calves naturally infected with gastrointestinal (GI) and pulmonary nematodes without clinical signs. For this, samples of feces and blood of 86 calves were collected. Fecal egg counts (FEC) were determined using the modified McMaster technique with a sensitivity of 50 eggs per gram of feces (EPG). Positive nematode FEC was processed for coproculture using pooled samples to identify Strongylidae infective larvae (L3). First stage-larvae (L1) of Dictyocaulus viviparous were identified by a modified Baermann method. The biochemical analytes determined were: acute phase proteins such as haptoglobin and paraoxonase type 1; the enzymes acetylcholinesterase; butyrylcholinesterase; the lipid profile (triglycerides and total, HDL, and LDL-cholesterol); serum iron profile (iron and unsaturated iron-binding capacity); total protein and albumin; pancreatic profile (amylase and lipase); and minerals (phosphorus and calcium). The calves were divided into four groups according to the results of EPG and the modified Baermann method. Group 1: healthy control animals (n=16); Group 2: calves with only GI parasites (n=51): This group was sub-divided into sub-groups according to the EPG threshold: 2a-GI parasites with low EPG (n=23), and 2b-GI parasites with high EPG (n=28). Group 3: animals with only lungworms (n=5), and Group 4: calves with lung+GI parasites (n=14). The more prevalent genera in all coprocultures were: Cooperia spp., Haemonchus spp., Oesophagostomum spp., and Trichostrongylus spp. The nonparametric Kruskal-Wallis test was used to compare the groups and Dunn's post-test was used for multiple comparisons as the data was not normally distributed (P<0.05). The haptoglobin concentration increased in calves with GI and pulmonary parasites. A

  16. Effect of vacuum packing and temperature on survival and hatching of strongyle eggs in faecal samples.

    PubMed

    Sengupta, Mita E; Thapa, Sundar; Thamsborg, Stig M; Mejer, Helena

    2016-02-15

    Strongyle eggs of helminths of livestock usually hatch within a few hours or days after deposition with faeces. This poses a problem when faecal sampling is performed in the field. As oxygen is needed for embryonic development, it is recommended to reduce air supply during transport and refrigerate. The present study therefore investigated the combined effect of vacuum packing and temperature on survival of strongyle eggs and their subsequent ability to hatch and develop into L3. Fresh faecal samples were collected from calves infected with Cooperia oncophora, pigs infected with Oesophagostomum dentatum, and horses infected with Strongylus vulgaris and cyathostomins. The samples were allocated into four treatments: vacuum packing and storage at 5 °C or 20 °C (5 V and 20 V); normal packing in plastic gloves closed with a loose knot and storage at 5 °C or 20 °C (5 N and 20 N). The number of eggs per gram faeces (EPG) was estimated every fourth day until day 28 post set up (p.s.) by a concentration McMaster-method. Larval cultures were prepared on day 0, 12 and 28 p.s. and the larval yield determined. For C. oncophora, the EPG was significantly higher in vacuum packed samples after 28 days as compared to normal storage, regardless of temperature. However, O. dentatum EPG was significantly higher in samples kept at 5 °C as compared to 20 °C, irrespective of packing. For the horse strongyles, vacuum packed samples at 5 °C had a significantly higher EPG compared to the other treatments after 28 days. The highest larval yield of O. dentatum and horse strongyles were obtained from fresh faecal samples, however, if storage is necessary prior to setting up larval cultures O. dentatum should be kept at room temperature (aerobic or anaerobic). However, horse strongyle coprocultures should ideally be set up on the day of collection to ensure maximum yield. Eggs of C. oncophora should be kept vacuum packed at room temperature for the highest larval yield. PMID:26827855

  17. Endectocide activity of a pour-on formulation containing 1.5 per cent ivermectin +0.5 per cent abamectin in cattle.

    PubMed

    Silva, Heloisa Cristina; Prette, Nancy; Lopes, Welber Daniel Zanetti; Sakamoto, Cláudio Alessandro M; Buzzulini, Carolina; Dos Santos, Thais Rabelo; Cruz, Breno Cayeiro; Teixeira, Weslen F Pires; Felippelli, Gustavo; Carvalho, Rafael Silveira; Maciel, Willian Giquelin; Soares, Vando Edésio; da Costa, Alvimar José

    2015-01-01

    The present work aimed to evaluate, through ten different studies, the therapeutic efficacy of a new pour-on formulation, containing 1.5 per cent ivermectin +0.5 per cent abamectin, against parasites of cattle. Results obtained on trials against Rhipicephalus (Boophilus) microplus showed that the pour-on combination of 1.5 per cent ivermectin +0.5 per cent abamectin obtained superior efficacy indexes against this ectoparasite, when compared with formulations containing 0.5 per cent ivermectin, 1 per cent ivermectin and the combination of 1 per cent abamectin +20 per cent levamisole. The results of efficacy of the ivermectin+abamectin and the 0.5 per cent ivermectin against Haematobia irritans were similar. Against Cochliomyia hominivorax larvae, all pour-on formulations tested (1.5 per cent ivermectin +0.5 per cent abamectin, 0.5 per cent ivermectin and 0.5 per cent abamectin), as well as 1 per cent doramectin administered subcutaneously, were considered ineffective. Cattle medicated with 1.5 per cent ivermectin +0.5 per cent abamectin, pour-on, remained free from parasitism by Dermatobia hominis larvae during 42 days (96 per cent efficacy), while values superior to 90 per cent were obtained by 0.5 per cent ivermectin (92 per cent) and 0.5 per cent abamectin (93 per cent) until the 42nd and 35th days post treatment, respectively. Against Haemonchus placei and Oesophagostomum radiatum, the pour-on of ivermectin+abamectin showed better efficacy than the 0.5 per cent ivermectin and 0.5 per cent abamectin. As to Cooperia punctata, there was no difference regarding efficacy results obtained by the avermectins combination and abamectin. The pour-on combination of 1.5 per cent ivermectin +0.5 per cent abamectin obtained high efficacy against R. (B.) microplus, D. hominis and some species of cattle gastrointestinal helminths when compared with formulations of 0.5 per cent ivermectin and 0.5 per cent abamectin administered through the same route. PMID:26392893

  18. New approach for the strategic control of gastrointestinal nematodes in grazed beef cattle during the growing phase in central Brazil.

    PubMed

    Heckler, R P; Borges, D G L; Vieira, M C; Conde, M H; Green, M; Amorim, M L; Echeverria, J T; Oliveira, T L; Moro, E; Van Onselen, V J; Borges, F A

    2016-05-15

    ) and November (T5 and T6). Haemonchus, Cooperia, Trichostrongylus and Oesophagostomum were identified. Treatments in May and November, the most common practice in Brazil, did not increase the final weight gain, so an additional and intermediate treatment during the dry season (August) is recommended. PMID:27084483

  19. Impact of eprinomectin on grazing behaviour and performance in dairy cattle with sub-clinical gastrointestinal nematode infections under continuous stocking management.

    PubMed

    Forbes, A B; Huckle, C A; Gibb, M J

    2004-11-10

    Forty spring-calving cows and heifers (20 of each) were allowed to acquire infection with gastrointestinal (GI) nematodes naturally during grazing. The control group (10 cows and 10 heifers) were compared with 20 similar animals treated with eprinomectin in order to evaluate the effect of GI nematodes on grazing behaviour, milk production, body condition score and live weight. The animals were paired according to parity and milk yield during the week prior to treatment, then within replicate pair randomly allocated to a different treatment group. The grazing area was sub-divided into 20 replicated paddocks of equivalent size and topography. Grazing pairs of either control or treated animals were randomly assigned to each paddock over the duration of the study (one pair per paddock). Grazing behaviour was recorded for both groups over a 10-day period commencing 4 days after treatment with eprinomectin. Milk yield was recorded daily and milk quality was recorded weekly. Live weight and body condition score were recorded on the day of allocation, the day of initial treatment and thereafter at weekly intervals until the end of the 4-week trial. Faecal samples were collected from each animal prior to, and after, allocation and submitted for counts of nematode eggs. Additional faecal samples were taken at the end of the study for culture and nematode identification. Individual faecal samples were also analysed for residual digestibility. Pasture samples for nematode larval counts were taken at the same time as faecal sampling. The parasitological results showed low levels of faecal nematode egg output throughout the study, with the heifers having higher counts than the cows. Faecal culture yielded species of Ostertagia, Cooperia, and Trichostrongylus. Pasture larval levels were very low throughout with no value exceeding 68 larvae/kg dry matter (DM) of herbage. There were significant (P < 0.05) effects of treatment on grazing time, eating time, total bites, total grazing

  20. Effects of sequential treatments with eprinomectin on performance and grazing behaviour in dairy cattle under daily-paddock stocking management.

    PubMed

    Gibb, M J; Huckle, C A; Forbes, A B

    2005-10-10

    .8 epg. Faecal culture yielded predominantly larvae of the genus Ostertagia, but the following genera were also identified: Cooperia, Oesophagostomum and Trichostrongylus. Pasture larval levels were also low with peak values of 135 and 58 L3/kg DM herbage (7 August) in the paddocks grazed by the control and treated cattle, respectively. Thereafter, larval counts on paddocks grazed by treated cows declined to undetectable levels by October, while control paddocks remained at approximately 40 L3/kg DM. There was no effect of treatment on components of grazing or ruminating behaviour recorded over 24 h or on short-term intake rates. There were significant differences between components of short-term intake rates measured during the morning and afternoon grazing meals. The overall milk yield response to treatment with eprinomectin was +1.68 kg/day solids-corrected milk (SCM) (P=0.026). The overall response included significant (P<0.050) increases in mean daily SCM yield following each of the three treatments, indicating a positive response to repeated treatments at several different stages of lactation. There were no significant differences in the overall percentages of fat, protein or lactose between control and treated groups. The differences in live weight were not significant, although there was a consistent pattern throughout for the treated cows to be heavier than the controls. PMID:16129562

  1. Comparative efficacy of ivermectin pour-on, albendazole, oxfendazole and fenbendazole against Ostertagia ostertagi inhibited larvae, other gastrointestinal nematodes and lungworm of cattle.

    PubMed

    Williams, J C; DeRosa, A; Nakamura, Y; Loyacano, A F

    1997-12-15

    An experiment was conducted to evaluate the current efficacy of albendazole (ABZ), oxfendazole (OXF) and fenbendazole (FBZ) compared with ivermectin pour-on (IVM-PO) against inhibited early fourth-stage larvae (IEL4) of Ostertagia ostertagi, other gastrointestinal nematodes and lungworm of cattle during spring in Louisiana. Twenty-five crossbred beef heifer calves of 235 kg average weight and 10-12 months of age were acquired in late winter and grazed for 9 weeks on pasture contaminated with O. ostertagi and other nematodes until May 15. The cattle were weighed and randomly allotted into 5 groups of 5 calves on May 16 (day 0) and treatments were as follows: group 1, nontreated controls (CONT); group 2, IVM-PO on mid-backline at 500 micrograms/kg; group 3, ABZ suspension (oral) at 10 mg/kg; group 4, OXF suspension (oral) at 4.5 mg/kg; group 5, FBZ suspension (oral) at 5 mg/kg. After treatment and confinement in separate pens for each group, approximately equal numbers of cattle from each group were necropsied daily between days 29-31. Mean numbers of O. ostertagi developmental stages present in CONT were: adult, 5234; developing (DL4), 3130; IEL4, 44,077. The mean percentage of IEL4 was 84.1. Cooperia spp. were the second most prevalent in CONT (20,307) and smaller numbers of abomasal and intestinal species and Dictyocaulus viviparus were present in nearly all CONT. Percent reductions for the four compounds against O. ostertagi adult, DL4 and IEL4, respectively, were IVM-PO: 99.7, 98.3, 98.1; ABZ: 74.1, 76.5, 75.3; OXF: 78.5, 42.1, 32.0; FBZ: 63.6, 17.7, 39.7. Efficacy of IVM-PO was greater (P < 0.05) against all O. ostertagi stages than the benzimidazole (BZ) drugs, except for ABZ (DL4). There were no significant differences in group means (except for C. punctata adult males, P < 0.05 lower for IVM-PO) or wide variation in reduction percentages for other abomasal and intestinal species and D. viviparus between IVM-PO and BZ drugs. The low efficacy of all three BZ