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Sample records for anthelmintic-resistant parascaris equorum

  1. Diagnosis and control of anthelmintic-resistant Parascaris equorum

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    Reinemeyer Craig R

    2009-09-01

    Full Text Available Abstract Since 2002, macrocyclic lactone resistance has been reported in populations of Parascaris equorum from several countries. It is apparent that macrocyclic lactone resistance developed in response to exclusive and/or excessively frequent use of ivermectin or moxidectin in foals during the first year of life. The development of anthelmintic resistance was virtually inevitable, given certain biological features of Parascaris and unique pharmacologic characteristics of the macrocyclic lactones. Practitioners can utilize the Fecal Egg Count Reduction Test to detect anthelmintic resistance in Parascaris, and the same technique can be applied regularly to confirm the continued efficacy of those drugs currently in use. In the face of macrocyclic lactone resistance, piperazine or anthelmintics of the benzimidazole or pyrimidine classes can be used to control ascarid infections, but Parascaris populations that are concurrently resistant to macrocyclic lactones and pyrimidine drugs have been reported recently from Texas and Kentucky. Compared to traditional practices, future recommendations for ascarid control should feature: 1 use of only those anthelmintics known to be effective against indigenous populations, 2 initiation of anthelmintic treatment no earlier than 60 days of age, and 3 repetition of treatments at the longest intervals which prevent serious environmental contamination with Parascaris eggs. In the interest of decreasing selection pressure for anthelmintic resistance, horse owners and veterinarians must become more tolerant of the passage of modest numbers of ascarid eggs by some foals. Anthelmintic resistance is only one of several potential responses to genetic selection. Although still only theoretical, changes in the immunogenicity of ascarid isolates or reduction of their prepatent or egg reappearance periods could pose far greater challenges to effective control than resistance to a single class of anthelmintics.

  2. The efficacy of ivermectin, pyrantel and fenbendazole against Parascaris equorum infection in foals on farms in Australia.

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    Armstrong, S K; Woodgate, R G; Gough, S; Heller, J; Sangster, N C; Hughes, K J

    2014-10-15

    This study was performed to estimate the prevalence of patent Parascaris equorum infections and determine the efficacy of ivermectin, pyrantel and fenbendazole against P. equorum infection in foals on farms in southern Australia. Foals aged >3 months on five farms in the south-western slopes region of New South Wales were used. Faeces were collected from each foal and foals with a P. equorum faecal egg count (FEC) of >100 eggs per gram (EPG) were used to measure anthelmintic efficacy using the FEC reduction (FECR) test, after random allocation to a control group or an ivermectin, pyrantel embonate or fenbendazole treatment group. Treatment was administered on day 0 and faeces were collected on day 14 and a FEC was performed. For determination of anthelmintic efficacy, FECRs and lower 95% confidence intervals (LCL) were calculated using previously described methods, based on individual or group FECRs. P. equorum populations were considered susceptible when FECR was >90% and LCL >90%, suspected resistant when FECR was FECR was 80-90% and LCL Fenbendazole was effective on two farms, equivocal on one farm and ineffective on one farm. Pyrantel embonate was effective on three farms and ineffective on one farm. These data indicate that anthelmintic-resistant P. equorum populations are present on farms in Australia and multiple drug resistance may occur on individual farms.

  3. Anthelmintic efficacy on Parascaris equorum in foals on Swedish studs

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    Christensson Dan

    2009-11-01

    Full Text Available Abstract Background In the last few years stud farms have experienced increasing problems with Parascaris equorum infections in foals despite intensive deworming programs. This has led to the question as to whether the anthelmintic drugs used against this parasite are failing. This study aimed to investigate the efficacy of ivermectin, fenbendazole and pyrantel on the faecal output of ascarid eggs of foals. Methods A Faecal Egg Count Reduction Test (FECRT was performed on nine large studs in Sweden. Anthelmintic drugs were given orally and faecal samples were examined for ascarid eggs on the day of deworming and 14 days later. Faecal Egg Count Reductions (FECRs were calculated on arithmetic means of transformed individual FECRs and on arithmetic means of individual FECRs. Results Seventy-nine (48% out of a total of 165 foals sampled were positive for P. equorum eggs before deworming and 66 of these met the criteria for being used in the efficacy assessment. It was shown that there was no, or very low activity of ivermectin on the output of ascarid eggs in the majority of the foals, whereas for fenbendazole and pyrantel it was >90%. Conclusion Ivermectin resistance was shown in 5 out of 6 farms. Therefore, ivermectin should not be the drug of choice in the control of P. equorum infections in foals. According to the results of this study, fenbendazole or pyrantel are still effective and should be used against this parasite.

  4. Viability of Rhodococcus equi and Parascaris equorum eggs exposed to high temperatures.

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    Hébert, Laurent; Cauchard, Julien; Doligez, Pauline; Quitard, Lola; Laugier, Claire; Petry, Sandrine

    2010-01-01

    There is great concern about the potential pathogen contamination of horse manure compost spread in the same fields horses graze in. To ensure that pathogen destruction occurs, temperatures need to be sufficiently high during composting. Here, we investigated the survival rate of two marker organisms, Rhodococcus equi and Parascaris equorum eggs, exposed to temperatures potentially encountered during horse manure composting. Our results show that the time required to achieve a 1 log10 reduction in R. equi population (D-value) are 17.1 h (+/-1.47) at 45 degrees C, 8.6 h (+/-0.28) at 50 degrees C, 2.9 h (+/-0.04) at 55 degrees C and 0.7 h (+/-0.04) at 60 degrees C. For P. equorum eggs we show that at 45 and 50 degrees C, 2 log10 reduction of viability is reached between 8 and 24 h of incubation and that it takes less than 2 h at 55 and 60 degrees C to achieve a viability reduction of 2 log10. These results are useful for identifying composting conditions that will reduce the risk of environmental contamination by R. equi and P. equorum eggs.

  5. The Effectiveness of Cinnamomum zeylanicum, Punica granatum Flower and Capsicum annuum Extracts Against Parascaris equorum Infective Larvae

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    Ehsan RAKHSHANDEHROO

    2016-07-01

    Full Text Available Recent investigations have shown that plants with medicinal peculiarities as good alternative to anthelmintics for livestock. In this study, the anthelmintic effects of three medicinal herbs (Cinnamomum zeylanicum, Punica granatum flower and Capsicum annuum were screened in vitro against the infective larvae of Parascaris equorum. The recovered larvae of the parasite were exposed to four concentrations (50, 75, 100 and 125 mg/mL of the extracts and then they examined for the viability at 0, 10, 20, 30 and 40 minutes after the challenge. The results revealed that all the concentrations of each plant extract had anthelmintic effects on P. equorum larvae. Also, the statistics indicated that there were significant interactions between the concentration of the extracts and time of exposure on the number of viable larvae. In addition, C. annuum extract seemed to be a strong potency to kill larvae at all concentrations from the beginning of the experiment. These results confirmed that those herbal extracts possess good antiparasitic effects against infective larvae of P. equorum and thus could be considered in anthelminth treatment strategies.

  6. Determination of ivermectin efficacy against cyathostomins and Parascaris equorum on horse farms using selective therapy

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    Larsen, Mette L.; Ritz, Christian; Petersen, Stig L.;

    2011-01-01

    cyathostomins and P. equorum in Danish horses. A total of 196 animals were selected from 52 farms, all of which were using a selective anthelmintic treatment strategy. ERP was investigated with weekly samples from 96 horses from nine farms. Horses were treated with ivermectin oral paste by their owners...... resistance were found in either cyathostomins or P. equorum in the studied horses....

  7. Anthelmintic resistance in equine nematodes

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    Matthews, Jacqueline B.

    2014-01-01

    Anthelmintics have been applied indiscriminately to control horse nematodes for over 40 years. Three broad-spectrum anthelmintic classes are currently registered for nematode control in horses: benzimidazoles (fenbendazole, oxibendazole), tetrahydropyrimidines (pyrantel) and macrocyclic lactones (ivermectin, moxidectin). Generally, control strategies have focused on nematode egg suppression regimens that involve the frequent application of anthelmintics to all horses at intervals based on strongyle egg reappearance periods after treatment. The widespread use of such programmes has substantially reduced clinical disease, especially that associated with large strongyle species; however, high treatment frequency has led to considerable selection pressure for anthelmintic resistance, particularly in cyathostomin species. Field studies published over the last decade indicate that benzimidazole resistance is widespread globally in cyathostomins and there are also many reports of resistance to pyrantel in these worms. Cyathostomin resistance to macrocyclic lactone compounds is emerging, principally measured as a reduction in strongyle egg reappearance time observed after treatment. Ivermectin resistance is a further concern in the small intestinal nematode, Parascaris equorum, an important pathogen of foals. These issues indicate that horse nematodes must now be controlled using methods less dependent on anthelmintic use and more reliant on management practices designed to reduce the force of infection in the environment. Such strategies include improved grazing management integrated with targeted anthelmintic administration involving faecal egg count (FEC)-directed treatments. The latter require that the supporting diagnostic tests available are robust and practically applicable. Recent research has focused on maximising the value of FEC analysis in horses and on optimizing protocols for anthelmintic efficacy testing. Other studies have sought to develop diagnostics

  8. Anthelmintic resistance in equine nematodes

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    Jacqueline B. Matthews

    2014-12-01

    Full Text Available Anthelmintics have been applied indiscriminately to control horse nematodes for over 40 years. Three broad-spectrum anthelmintic classes are currently registered for nematode control in horses: benzimidazoles (fenbendazole, oxibendazole, tetrahydropyrimidines (pyrantel and macrocyclic lactones (ivermectin, moxidectin. Generally, control strategies have focused on nematode egg suppression regimens that involve the frequent application of anthelmintics to all horses at intervals based on strongyle egg reappearance periods after treatment. The widespread use of such programmes has substantially reduced clinical disease, especially that associated with large strongyle species; however, high treatment frequency has led to considerable selection pressure for anthelmintic resistance, particularly in cyathostomin species. Field studies published over the last decade indicate that benzimidazole resistance is widespread globally in cyathostomins and there are also many reports of resistance to pyrantel in these worms. Cyathostomin resistance to macrocyclic lactone compounds is emerging, principally measured as a reduction in strongyle egg reappearance time observed after treatment. Ivermectin resistance is a further concern in the small intestinal nematode, Parascaris equorum, an important pathogen of foals. These issues indicate that horse nematodes must now be controlled using methods less dependent on anthelmintic use and more reliant on management practices designed to reduce the force of infection in the environment. Such strategies include improved grazing management integrated with targeted anthelmintic administration involving faecal egg count (FEC-directed treatments. The latter require that the supporting diagnostic tests available are robust and practically applicable. Recent research has focused on maximising the value of FEC analysis in horses and on optimizing protocols for anthelmintic efficacy testing. Other studies have sought to develop

  9. Anthelmintic resistance of intestinal nematodes to ivermectin and pyrantel in Estonian horses.

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    Lassen, B; Peltola, S-M

    2015-11-01

    There is evidence of resistance in horses to anthelmintic treatment using ivermectin and pyrantel. However, little information is available about the parasites, treatment practices or anthelmintic resistance in the horse population in Estonia. In the present study, we examined 41 trotting and riding horses aged < 3 years from four stables in Estonia. Faecal samples were collected, and horses were selected for treatment if the nematode egg count per gram faeces exceeded 200. Horses (n= 32) that shed strongyle-type eggs were treated with pyrantel, whereas Parascaris equorum-positive animals received ivermectin. Up to 78% of horses required anthelmintic treatment and the efficiency of the anthelmintics was evaluated using a faecal egg count reduction test. Resistance of P. equorum was observed in 50% of horses treated with ivermectin and of strongyles in 27% of horses treated with pyrantel. Ivermectin treatment resulted in a mean reduction of 100% for strongyle eggs and an 89% reduction in P. equorum, and pyrantel-treated horses exhibited an 88% reduction in strongyle eggs. These results are considered to be the first indication of resistance to pyrantel, but further studies of ivermectin resistance are required. According to questionnaires completed by the owners of horses, resistance might be explained by a lack of evidence-based strategies, a strong preference for using ivermectin and possibly a subjective evaluation of the body weight of horses.

  10. Further evaluation in field tests of the activity of three anthelmintics (fenbendazole, oxibendazole, and pyrantel pamoate) against the ascarid Parascaris equorum in horse foals on eight farms in Central Kentucky (2009-2010).

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    Lyons, Eugene T; Tolliver, Sharon C; Kuzmina, Tetiana A; Collins, Sandra S

    2011-10-01

    The activity of three anthelmintics (fenbendazole-FBZ; oxibendazole-OBZ; and pyrantel pamoate-PRT) was ascertained against the ascarid Parascaris equorum in horse foals on eight farms in Central Kentucky (2009-2010) in field tests. A total of 316 foals were treated, and 168 (53.2%) were passing ascarid eggs on the day of treatment. Evaluation of drug efficacy was determined qualitatively by comparing the number of foals passing ascarid eggs in their feces before and after treatment. The main purpose was to obtain data on current activity of these compounds against ascarids. Additionally, the objective was to compare these findings with those from earlier data on the efficacy of these three compounds on nematodes in foals in this geographical area. Efficacies (average) for the foals ranged for FBZ (10 mg/kg) from 50% to 100% (80%), for OBZ (10 mg/kg) from 75% to 100% (97%), and for PRT at 1× (6.6 mg base/kg) from 0% to 71% (2%) and at 2× (13.2 mg base/kg) 0% to 0% (0%). Although the efficacy varied among the drugs, combined data for all farms indicated a significant reduction of ascarid infections for FBZ (p < 0.0001) and OBZ (p < 0.0001) but not for PRT (p = 0.0953).

  11. Anthelmintics Resistance; How to Overcome it?

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    Hatem A Shalaby

    2013-03-01

    Full Text Available Many parasitic helminthes of veterinary importance have genetic features that favor development of anthelmintic resistance, this becoming a major worldwide constrain in livestock production. The develop­ment of anthelmintic resistance poses a large threat to future production and welfare of graz­ing animals. Development of variable degrees of resistance among different species of gastrointes­tinal nematodes has been reported for all the major groups of anthelmintic drugs. It has been ob­served that frequent usage of the same group of anthelmintic; use of anthelmintics in sub-optimal doses, prophylactic mass treatment of domestic animals and frequent and continuous use of a single drug have contributed to the widespread development of anthelmintic resistance in helminthes. The degree and extent of this problem especially with respect to multidrug resistance in nematode popula­tions is likely to increase. Maintaining parasites in refugia and not exposed to anthelmintics, seems to be a key point in controlling and delaying the development of resistance, because the suscepti­ble genes are preserved. Targeted selective treatments attract the interest of scientists to­wards this direction. Additionally, adoption of strict quarantine measures and a combination drug strategy are two important methods of preventing of anthelmintic resistance. Experience from the development of anthelmintic resistance suggests that modern control schemes should not rely on sole use of anthelmintics, but employ other, more complex and sustainable recipes, including parasite resistant breeds, nutrition, pasture management, nematode-trapping fungi, antiparasitic vaccines and botanical dewormers. Most of them reduce reliance on the use of chemicals and are environmental friendly. Finally, if new anthelmintic products are released, an important question will be raised about how they should be used. It is suggested that slowing the development of resistance to a new

  12. Recent advances in diagnosing pathogenic equine gastrointestinal helminths

    DEFF Research Database (Denmark)

    Andersen, Ulla Vestergaard; Howe, D. K.; Olsen, Susanne Nautrup;

    2013-01-01

    Parasites infecting horses are ubiquitous and clinically important across the world. The major parasitic threats to equine health are cyathostomins, Parascaris equorum, Anoplocephala perfoliata, and Strongylus vulgaris. Increasing levels of anthelmintic resistance reported world wide in equine pa...

  13. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds

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    Holm, Signe A.; Sørensen, Camilla; Thamsborg, Stig M.;

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met the inclu...

  14. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds☆

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    Holm Signe A.

    2014-01-01

    Full Text Available The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR in 10 selected herds were investigated during April–September 2012. All Danish herds (n = 137 with 10 or more adult goats were invited to participate, and of these 27 herds met the inclusion criterion of more than 10 young kids never treated with anthelmintics. Questionnaire data on management were collected, and faecal samples from 252 kids were analysed by the McMaster technique. From all herds with a mean faecal egg count (FEC above 300 eggs per g of faeces, pooled samples were stained with peanut agglutinin (PNA for specific detection of Haemonchus contortus. Strongyle eggs were detected with an individual prevalence of 69%, including Nematodirus battus (3.6% and other Nematodirus species (15.0%. Eimeria spp. were observed in 99.6% of the kids. H. contortus was found in 11 of 12 (92% tested herds. Anthelmintics were used in 89% of the herds with mean treatment frequencies of 0.96 and 0.89 treatments per year for kids and adults, respectively. In 2011, new animals were introduced into 44% of the herds of which 25% practised quarantine anthelmintic treatments. In 10 herds the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg or fenbendazole (10.0 mg/kg. AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark.

  15. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds.

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    Holm, Signe A; Sörensen, Camilla R L; Thamsborg, Stig M; Enemark, Heidi L

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met the inclusion criterion of more than 10 young kids never treated with anthelmintics. Questionnaire data on management were collected, and faecal samples from 252 kids were analysed by the McMaster technique. From all herds with a mean faecal egg count (FEC) above 300 eggs per g of faeces, pooled samples were stained with peanut agglutinin (PNA) for specific detection of Haemonchus contortus. Strongyle eggs were detected with an individual prevalence of 69%, including Nematodirus battus (3.6%) and other Nematodirus species (15.0%). Eimeria spp. were observed in 99.6% of the kids. H. contortus was found in 11 of 12 (92%) tested herds. Anthelmintics were used in 89% of the herds with mean treatment frequencies of 0.96 and 0.89 treatments per year for kids and adults, respectively. In 2011, new animals were introduced into 44% of the herds of which 25% practised quarantine anthelmintic treatments. In 10 herds the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg) or fenbendazole (10.0 mg/kg). AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark.

  16. Evaluation of anthelmintic resistance in livestock parasites using observational data and hierarchical models

    DEFF Research Database (Denmark)

    Nielsen, Martin Krarup; Vidyashankar, Anand N.; Hanlon, Bret;

    Anthelmintic resistance is an increasing challenge in the control of parasites in livestock. The fecal egg count reduction test (FECRT) is the practical gold standard method for evaluating resistance, but the interpretation is complicated due to high levels of variability. Several factors...... to handle FECRT data obtained from other livestock species, drug types, and parasite species....

  17. First Report of Anthelmintic Resistance in Gastrointestinal Nematodes of Sheep from Costa Rica

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    Maroto, R.; Jiménez, A. E.; Romero, J. J.; Alvarez, V.; De Oliveira, J. B.; Hernández, J.

    2011-01-01

    As the prevalence and severity of anthelmintic resistance continue to rise, nematode infections in sheep correspondingly reduce the profitability of the sheep industry. In Costa Rica, sheep production systems are increasing in both number and importance. A field trial study was carried out to detect the level of anthelmintic resistance to albendazole and ivermectin in gastrointestinal nematodes (GIN) of sheep from seven farms in Costa Rica. Resistance was determined using the fecal egg count reduction test (FECRT). Three treatment groups were assessed on each farm: control, albendazole, and ivermectin. Haemonchus spp. (71%), Strongyloides sp. (57%), and Trichostrongylus spp. (43%) presented resistance levels to albendazole, whereas Strongyloides sp. (43%), Haemonchus spp. (29%), and Trichostrongylus spp. (29%) were resistant to ivermectin. Haemonchus spp., Strongyloides sp., and Trichostrongylus spp. were the most resistant GIN to both products. This study suggests that frequency of treatment, exclusive chemical control, and visual estimation of animal weight to calculate dosage may contribute to the high levels of anthelmintic resistance that were observed on the farms analyzed herein. PMID:21772962

  18. First Report of Anthelmintic Resistance in Gastrointestinal Nematodes of Sheep from Costa Rica

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    R. Maroto

    2011-01-01

    Full Text Available As the prevalence and severity of anthelmintic resistance continue to rise, nematode infections in sheep correspondingly reduce the profitability of the sheep industry. In Costa Rica, sheep production systems are increasing in both number and importance. A field trial study was carried out to detect the level of anthelmintic resistance to albendazole and ivermectin in gastrointestinal nematodes (GIN of sheep from seven farms in Costa Rica. Resistance was determined using the fecal egg count reduction test (FECRT. Three treatment groups were assessed on each farm: control, albendazole, and ivermectin. Haemonchus spp. (71%, Strongyloides sp. (57%, and Trichostrongylus spp. (43% presented resistance levels to albendazole, whereas Strongyloides sp. (43%, Haemonchus spp. (29%, and Trichostrongylus spp. (29% were resistant to ivermectin. Haemonchus spp., Strongyloides sp., and Trichostrongylus spp. were the most resistant GIN to both products. This study suggests that frequency of treatment, exclusive chemical control, and visual estimation of animal weight to calculate dosage may contribute to the high levels of anthelmintic resistance that were observed on the farms analyzed herein.

  19. A survey on anthelmintic resistance in nematode parasites of sheep in the Slovak Republic.

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    Cernanská, D; Várady, M; Corba, J

    2006-01-15

    The prevalence of anthelmintic resistance on 27 sheep farms in Slovakia was investigated in 2003 and 2004 using the faecal egg count reduction test (FECRT) according to the WAAVP guidelines. Resistance to albendazole was detected on one farm (3.7%) and suspected on two farms (7.4%) out of 27 sheep flocks. Resistance to ivermectin was tested on 26 farms. On six (23.1%) farms, results indicated the presence of ivermectin resistance. Resistance to ivermectin was suspected on eight farms (30.8%). However, it is also possible that generic ivermectin anthelmintics used in survey have a lower efficacy against sheep nematodes.

  20. Comparison of two versions of larval development test to detect anthelmintic resistance in Haemonchus contortus.

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    Várady, Marián; Corba, Július; Letková, Valéria; Kovác, Gabriel

    2009-03-23

    Larval development (LDT) and micro-agar larval development tests (MALDT) were used to compare the reliability and sensitivity of two methods for detecting anthelmintic resistance in Haemonchus contortus. The tests were conducted using three resistant and four susceptible isolates of H. contortus. Both versions of the tests provided comparable results with regard to the characterization of benzimidazole and levamisole susceptibility but neither test was sufficiently sensitive to discrimination between an ivermectin (IVM) susceptible and an IVM resistant isolate. Each test has its own merits with the LDT having the advantage of being less time-consuming.

  1. Anthelmintic resistance of nematodes in communally grazed goats in a semi-arid area of South Africa

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    F.R. Bakunzi

    2003-07-01

    Full Text Available A survey was conducted on the occurrence of anthelmintic resistance of nematodes in communally grazed goats in a semi-arid area in SouthAfrica. In herds belonging to 10 smallholder goat farmers, the efficacies of fenbendazole, levamisole and rafoxanide were tested by faecal egg count reduction (FECR tests. Efficacies of 80 % were considered a threshold for anthelmintic resistance. The FECR tests showed that all drugs tested more than 80 % effective in most instances, but there were notable exceptions. In 1 case, rafoxanide was only 31 % effective and in another case fenbendazole was only 47 % effective. The occurrence of anthelmintic resistance in this farming sector is of concern. Steps should be taken to prevent its further spread and to avoid the development of a situation as onnumerous commercial sheep farms in South Africa where resistance is very common.

  2. Overview of anthelmintic resistance of gastrointestinal nematodes of small ruminants in Brazil.

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    Salgado, Jordana Andrioli; Santos, Clóvis de Paula

    2016-01-01

    Frequent and inappropriate use of all classes of antiparasitic drugs in small ruminants has led to failures in their effectiveness, culminating in a global problem of anthelmintic resistance. Brazil stands out as one of the world's leaders in publications about anthelmintic resistance, and for having the most numerous reports of this resistance in small ruminants in the Americas. These studies have involved mainly the fecal egg count reduction test (FECRT) and its correlation with field management practices. In vivoeffectiveness testing is conducted in areas where livestock is of greater economic significance, e.g., in the South (sheep) and Northeast (goats), or is important for research and economic centers, such as the Southeast (sheep). The most widely studied species is sheep, for which the widest range of drugs is also evaluated. Despite significant advances achieved in molecular research, laboratory analyses should include knowledge about the reality in the field so that they can become feasible for the producer. Moreover, molecular studies can be underpinned by the analysis of field studies, such as the maintenance of antiparasitic effectiveness over time and the mechanisms involved in this process. PMID:26982560

  3. Wild deer as potential vectors of anthelmintic-resistant abomasal nematodes between cattle and sheep farms.

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    Chintoan-Uta, C; Morgan, E R; Skuce, P J; Coles, G C

    2014-04-01

    Gastrointestinal (GI) nematodes are among the most important causes of production loss in farmed ruminants, and anthelmintic resistance is emerging globally. We hypothesized that wild deer could potentially act as reservoirs of anthelmintic-resistant GI nematodes between livestock farms. Adult abomasal nematodes and faecal samples were collected from fallow (n = 24), red (n = 14) and roe deer (n = 10) from venison farms and areas of extensive or intensive livestock farming. Principal components analysis of abomasal nematode species composition revealed differences between wild roe deer grazing in the areas of intensive livestock farming, and fallow and red deer in all environments. Alleles for benzimidazole (BZ) resistance were identified in β-tubulin of Haemonchus contortus of roe deer and phenotypic resistance confirmed in vitro by an egg hatch test (EC50 = 0.149 µg ml(-1) ± 0.13 µg ml(-1)) on H. contortus eggs from experimentally infected sheep. This BZ-resistant H. contortus isolate also infected a calf experimentally. We present the first account of in vitro BZ resistance in wild roe deer, but further experiments should firmly establish the presence of phenotypic BZ resistance in vivo. Comprehensive in-field studies should assess whether nematode cross-transmission between deer and livestock occurs and contributes, in any way, to the development of resistance on livestock farms.

  4. A survey of anthelmintic resistance on ten sheep farms in Mashonaland East Province, Zimbabwe : research communication

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    S. Mukaratirwa

    1997-07-01

    Full Text Available A survey to detect anthelmintic resistance in nematode parasites of sheep was conducted on 10 randomly-distributed farms in the Chivhu District, Mashonaland East Province, Zimbabwe. Before the survey, a questionnaire was circulated to the farmers concerning nematode parasite control. Results showed that parasite control using anthelmintic treatment was the only method practised and that the benzimidazoles were the most frequently used anthelmintic drugs. The faecal egg count reduction test was used to detect resistance. The anthelmintic groups tested were benzimidazoles, levamisole and ivermectin. Resistance to benzimidazoles was detected on 6 of 10 farms and levamisole resistance on 2 of 3 farms. Ivermectin resistance was not observed on the farms surveyed. Post-treatment larval cultures indicated that Haemonchus contortus survived administration of fenbendazole, albendazole, oxfendazole and levamisole. A Cooperia sp. strain resistant to albendazole was detected and this is the first report in Zimbabwe of a resistant parasite in this genus.

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

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    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

    2015-12-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Carlos M.B. Gárcia

    2016-03-01

    Full Text Available 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.

  7. Recent advances in candidate-gene and whole-genome approaches to the discovery of anthelmintic resistance markers and the description of drug/receptor interactions

    Science.gov (United States)

    Kotze, Andrew C.; Hunt, Peter W.; Skuce, Philip; von Samson-Himmelstjerna, Georg; Martin, Richard J.; Sager, Heinz; Krücken, Jürgen; Hodgkinson, Jane; Lespine, Anne; Jex, Aaron R.; Gilleard, John S.; Beech, Robin N.; Wolstenholme, Adrian J.; Demeler, Janina; Robertson, Alan P.; Charvet, Claude L.; Neveu, Cedric; Kaminsky, Ronald; Rufener, Lucien; Alberich, Melanie; Menez, Cecile; Prichard, Roger K.

    2014-01-01

    Anthelmintic resistance has a great impact on livestock production systems worldwide, is an emerging concern in companion animal medicine, and represents a threat to our ongoing ability to control human soil-transmitted helminths. The Consortium for Anthelmintic Resistance and Susceptibility (CARS) provides a forum for scientists to meet and discuss the latest developments in the search for molecular markers of anthelmintic resistance. Such markers are important for detecting drug resistant worm populations, and indicating the likely impact of the resistance on drug efficacy. The molecular basis of resistance is also important for understanding how anthelmintics work, and how drug resistant populations arise. Changes to target receptors, drug efflux and other biological processes can be involved. This paper reports on the CARS group meeting held in August 2013 in Perth, Australia. The latest knowledge on the development of molecular markers for resistance to each of the principal classes of anthelmintics is reviewed. The molecular basis of resistance is best understood for the benzimidazole group of compounds, and we examine recent work to translate this knowledge into useful diagnostics for field use. We examine recent candidate-gene and whole-genome approaches to understanding anthelmintic resistance and identify markers. We also look at drug transporters in terms of providing both useful markers for resistance, as well as opportunities to overcome resistance through the targeting of the transporters themselves with inhibitors. Finally, we describe the tools available for the application of the newest high-throughput sequencing technologies to the study of anthelmintic resistance. PMID:25516826

  8. Recent advances in candidate-gene and whole-genome approaches to the discovery of anthelmintic resistance markers and the description of drug/receptor interactions

    Directory of Open Access Journals (Sweden)

    Andrew C. Kotze

    2014-12-01

    Full Text Available Anthelmintic resistance has a great impact on livestock production systems worldwide, is an emerging concern in companion animal medicine, and represents a threat to our ongoing ability to control human soil-transmitted helminths. The Consortium for Anthelmintic Resistance and Susceptibility (CARS provides a forum for scientists to meet and discuss the latest developments in the search for molecular markers of anthelmintic resistance. Such markers are important for detecting drug resistant worm populations, and indicating the likely impact of the resistance on drug efficacy. The molecular basis of resistance is also important for understanding how anthelmintics work, and how drug resistant populations arise. Changes to target receptors, drug efflux and other biological processes can be involved. This paper reports on the CARS group meeting held in August 2013 in Perth, Australia. The latest knowledge on the development of molecular markers for resistance to each of the principal classes of anthelmintics is reviewed. The molecular basis of resistance is best understood for the benzimidazole group of compounds, and we examine recent work to translate this knowledge into useful diagnostics for field use. We examine recent candidate-gene and whole-genome approaches to understanding anthelmintic resistance and identify markers. We also look at drug transporters in terms of providing both useful markers for resistance, as well as opportunities to overcome resistance through the targeting of the transporters themselves with inhibitors. Finally, we describe the tools available for the application of the newest high-throughput sequencing technologies to the study of anthelmintic resistance.

  9. Variability in faecal egg counts – a statistical model to achieve reliable determination of anthelmintic resistance in livestock

    DEFF Research Database (Denmark)

    Nielsen, Martin Krarup; Vidyashankar, Anand N.; Hanlon, Bret;

    Anthelmintic resistance is an increasing challenge for the control of parasites in livestock. The faecal egg count reduction test (FECRT) is the practical gold standard method for evaluating resistance, but the interpretation is complicated due to high levels of variability. A hierarchical...... arithmetic calculations classified nine farms (14.1 %) as resistant and 11 farms (17.2 %) as suspect resistant. Using 10000 Monte Carlo simulated data sets, our methodology provides a reliable classification of farms into different resistance categories with a false discovery rate of 1.02 %. The methodology...

  10. Managing anthelmintic resistance--parasite fitness, drug use strategy and the potential for reversion towards susceptibility.

    Science.gov (United States)

    Leathwick, Dave M

    2013-11-15

    The rotation of different anthelmintic classes, on an approximately annual basis, has been widely promoted and adopted as a strategy to delay the development of anthelmintic resistance in nematode parasites. Part of the rationale for recommending this practice was the expectation that resistant genotype worms have a lower ecological fitness than susceptible worms, at least in the early stages of selection, and so reversion towards susceptibility could be expected in those years when an alternative class of anthelmintic was used. The routine use of combination anthelmintics might be expected to negate this opportunity for reversion because multiple classes of anthelmintic would be used simultaneously. A simulation model was used to investigate whether the optimal strategy for use of multiple drug classes (i.e. an annual rotation of two classes of anthelmintic or continuous use of two classes in combination) changed with the size of the fitness cost associated with resistance. Model simulations were run in which the fitness cost associated with each resistance gene was varied from 0% to 15% and the rate at which resistance developed was compared for each of the drug-use strategies. Other factors evaluated were the initial frequency of the resistance genes and the proportion of the population not exposed to treatment (i.e. in refugia). Increasing the proportion of the population in refugia always slowed the development of resistance, as did using combinations in preference to an annual rotation. As the fitness cost associated with resistance increased, resistance developed more slowly and this was more pronounced when a combination was used compared to a rotation. If the fitness cost was sufficiently high then resistance did not develop (i.e. the resistance gene frequency declined over time) and this occurred at lower fitness costs when a combination was used. The results, therefore, indicate that the optimal drug-use strategy to maximise the benefit of any fitness

  11. Anthelmintic-resistant strains of Haemonchus contortus and Trichostrongylus colubriformis isolated from an organic sheep and goat farm in Denmark

    DEFF Research Database (Denmark)

    Pena-Espinoza, Miguel Angel; Enemark, Heidi L.; Thansborg, Stig M.

    2013-01-01

    ) or 10 mg/kg closantel (CLO). Kids were treated with 10 mg/kg FBZ, 0.3 mg/kg MOX, 14 mg/kg LEV, 0.2 mg/kg IVM or 10 mg/kg CLO. FECs were performed at day of treatment and 14 days post treatment. In a subsequent investigation, faeces from adult goats were cultured to obtain 3rd-stage nematode larvae (L3......A suspected case of anthelmintic resistance (AR) was investigated in an organic dairy sheep and goat farm. The herd was established in 2007 by purchase of animals from a number of other farms. Selection for the study was based on history of anthelmintic-treatment failure. Forty-eight lambs and 48...... %. This is the first isolation of BZ-resistant H. contortus and T. colubriformis in Denmark and highlights the need for continuous surveillance of AR in conventional and organic farms....

  12. Use of two in vitro methods for the detection of anthelmintic resistant nematode parasites on Slovak sheep farms.

    Science.gov (United States)

    Várady, Marián; Cernanská, Dana; Corba, Július

    2006-02-18

    A survey of the prevalence of anthelmintic resistant nematode populations was conducted on 32 sheep farms in the Slovak Republic. In vitro egg hatch test and larval development tests were used for the detection of resistance to benzimidazole anthelmintics and they were compared with in vivo faecal egg count reduction tests. There was agreement in the declaration of resistance between the faecal egg count reduction test and both in vitro tests. The presence of resistant populations was determined on two farms using egg hatch test. In both farms, the LD(50) values were higher than 0.1 microg TBZ/ml, indicating resistance. By using LD(99) values it might be possible to reveal relatively small proportion of resistant larvae in the population. The prevalence of benzimidazole resistance has not change on Slovak sheep farms during last decade.

  13. A comparison of in vitro tests and a faecal egg count reduction test in detecting anthelmintic resistance in horse strongyles

    DEFF Research Database (Denmark)

    Craven, J.; Bjørn, H.; Barnes, E.H.;

    1999-01-01

    This study reports a comparison between faecal egg count reduction test (FECRT), egg hatch assay (EHA) and larval development assay (LDA) for detecting anthelmintic resistance in equine strongyles. Resistance to benzimidazoles was demonstrated in 33 of 42 (79%) farms tested by FECRT and in 32 (62......%) of the 52 farms tested by EHA. As the reference strain used was not fully susceptible to benzimidazoles it was not possible to determine the level of resistance by LDA. Pyrantel resistance was indicated on three of 15 farms by faecal egg count reduction. Resistance was also indicated by LDA for one...... of these farms. In addition resistance was indicated by LDA on two more farms that were not tested by FECRT. Further testing is needed to confirm if these findings are truly indicative of resistance. Generally, correlations between the tests were poor and it was not possible to use the outcome of one test...

  14. Managing anthelmintic resistance: is it feasible in New Zealand to delay the emergence of resistance to a new anthelmintic class?

    Science.gov (United States)

    Leathwick, D M; Hosking, B C; Bisset, S A; McKay, C H

    2009-08-01

    The recent registration in New Zealand of the first new class of broad-spectrum anthelmintic, for use against nematode parasites of ruminants, in nearly three decades has raised the possibility that parasite management practices could be improved to minimise the emergence of resistance to the new drug. A review of knowledge pertaining to the selection of anthelmintic resistance in nematode parasites of sheep highlights a number of management practices which could be altered to achieve this. A number of previously common practices such as whole-flock treatment of adult ewes around lambing, and treatment of lambs as they are moved onto pastures with low parasite contamination have been clearly identified as high risk for selecting resistant parasites. Once high-risk practices have been identified steps can be taken to either eliminate their use or mitigate the associated risk. Much of the focus on the management of resistance around the world is on the retention of susceptible genotypes in refugia. While approaches to retaining unselected parasites are likely to vary around the world, empirical studies indicate that the practice is likely to be effective at slowing the development of resistance. The challenge for farmers and advisors will be to strike a balance between retaining sufficient susceptible parasites to usefully delay the development of resistance while not unduly compromising animal performance and farm profitability. The merits of combining different classes of anthelmintic in order to slow the development of resistance remains somewhat contentious in some countries. However, the attributes of oral anthelmintics are such that they seem likely to meet most, if not all, of the criteria for combinations to be highly effective at slowing the build-up of resistance in nematode parasites. It is evident that considerable progress has been made in understanding the factors involved in selecting anthelmintic-resistant nematodes since the last broad

  15. Comparison of calculation methods used for the determination of anthelmintic resistance in sheep in a temperate continental climate.

    Science.gov (United States)

    Falzon, L C; van Leeuwen, J; Menzies, P I; Jones-Bitton, A; Sears, W; Jansen, J T; Peregrine, A S

    2015-04-01

    This study compared results obtained with five different fecal egg count reduction (FECR) calculation methods for defining resistance to ivermectin, fenbendazole, and levamisole in gastrointestinal nematodes of sheep in a temperate continental climate: FECR1 and FECR2 used pre-and posttreatment fecal egg count (FEC) means from both treated and control animals, but FECR1 used arithmetic means, whereas FECR2 used geometric means; FECR3 used arithmetic means for pre- and posttreatment FECs from treated animals only; FECR4 was calculated using only arithmetic means for posttreatment FECs from treated and control animals; and FECR5 was calculated using mean FEC estimates from a general linear mixed model. The classification of farm anthelmintic resistance (AR) status varied, depending on which FECR calculation method was used and whether a bias correction term (BCT, i.e., half the minimum detection limit) was added to the zeroes or not. Overall, agreement between all methods was higher when a BCT was used, particularly when levels of resistance were low. FECR4 showed the highest agreement with all the other FECR methods. We therefore recommend that small ruminant clinicians use the FECR4 formula with a BCT for AR determination, as this would reduce the cost of the FECRT, while still minimizing bias and allowing for comparisons between different farms. For researchers, we recommend the use of FECR1 or FECR2, as the inclusion of both pre- and posttreatment FECs and use of randomly allocated animals in treatment and control groups makes these methods mathematically more likely to estimate the true anthelmintic efficacy.

  16. F200Y polymorphism of the β-tubulin isotype 1 gene in Haemonchus contortus and sheep flock management practices related to anthelmintic resistance in eastern Amazon.

    Science.gov (United States)

    Chagas, Alexandre Moura; Sampaio Junior, Francisco Dantas; Pacheco, Adlilton; da Cunha, Amanda Batista; Cruz, Juliana Dos Santos; Scofield, Alessandra; Góes-Cavalcante, Gustavo

    2016-08-15

    The objective of the present study was to determine the frequency of the F200Y polymorphism in the β-tubulin isotype 1 gene of Haemonchus contortus from various sheep flocks in eastern Amazon, and to identify management practices that may favor the emergence of resistance to anthelmintic drugs in the same area. In total, 305 specimens of H. contortus were collected from sheep at 12 farms located in the state of Pará. An allele-specific PCR was performed to detect the F200Y polymorphism, and questionnaires were used to obtain information about the farms and flocks. All genotypes were detected as follows: 31% of the parasites were RR, 37% of the parasites were SR, and 32% were SS. The completed questionnaires revealed that all farms employed semi-intensive farming systems, performed suppressive anthelmintic treatment, and based their choice of drug on cost and availability rather than on any knowledge regarding drugs that remained effective on their property. It can thus be concluded that the SNP in codon 200 of the β-tubulin isotype 1 gene is present in the H. contortus populations from eastern Amazon, and that a series of management practices that favor the emergence of anthelmintic resistance are employed on these farms.

  17. F200Y polymorphism of the β-tubulin isotype 1 gene in Haemonchus contortus and sheep flock management practices related to anthelmintic resistance in eastern Amazon.

    Science.gov (United States)

    Chagas, Alexandre Moura; Sampaio Junior, Francisco Dantas; Pacheco, Adlilton; da Cunha, Amanda Batista; Cruz, Juliana Dos Santos; Scofield, Alessandra; Góes-Cavalcante, Gustavo

    2016-08-15

    The objective of the present study was to determine the frequency of the F200Y polymorphism in the β-tubulin isotype 1 gene of Haemonchus contortus from various sheep flocks in eastern Amazon, and to identify management practices that may favor the emergence of resistance to anthelmintic drugs in the same area. In total, 305 specimens of H. contortus were collected from sheep at 12 farms located in the state of Pará. An allele-specific PCR was performed to detect the F200Y polymorphism, and questionnaires were used to obtain information about the farms and flocks. All genotypes were detected as follows: 31% of the parasites were RR, 37% of the parasites were SR, and 32% were SS. The completed questionnaires revealed that all farms employed semi-intensive farming systems, performed suppressive anthelmintic treatment, and based their choice of drug on cost and availability rather than on any knowledge regarding drugs that remained effective on their property. It can thus be concluded that the SNP in codon 200 of the β-tubulin isotype 1 gene is present in the H. contortus populations from eastern Amazon, and that a series of management practices that favor the emergence of anthelmintic resistance are employed on these farms. PMID:27514894

  18. Unique Characteristics of Recombinant Hybrid Manganese Superoxide Dismutase from Staphylococcus equorum and S. saprophyticus.

    Science.gov (United States)

    Retnoningrum, Debbie S; Rahayu, Anis Puji; Mulyanti, Dina; Dita, Astrid; Valerius, Oliver; Ismaya, Wangsa T

    2016-04-01

    A recombinant hybrid of manganese dependent-superoxide dismutase of Staphylococcus equorum and S. saprophyticus has successfully been overexpressed in Escherichia coli BL21(DE3), purified, and characterized. The recombinant enzyme suffered from degradation and aggregation upon storage at -20 °C, but not at room temperature nor in cold. Chromatographic analysis in a size exclusion column suggested the occurrence of dimeric form, which has been reported to contribute in maintaining the stability of the enzyme. Effect of monovalent (Na(+), K(+)), divalent (Ca(2+), Mg(2+)), multivalent (Mn(2+/4+), Zn(2+/4+)) cations and anions (Cl(-), SO4 (2-)) to the enzyme stability or dimeric state depended on type of cation or anion, its concentration, and pH. However, tremendous effect was observed with 50 mM ZnSO4, in which thermostability of both the dimer and monomer was increased. Similar situation was not observed with MnSO4, and its presence was detrimental at 200 mM. Finally, chelating agent appeared to destabilize the dimer around neutral pH and dissociate it at basic pH. The monomer remained stable upon addition of ethylene diamine tetraacetic acid. Here we reported unique characteristics and stability of manganese dependent-superoxide dismutase from S. equorum/saprophyticus.

  19. Unique Characteristics of Recombinant Hybrid Manganese Superoxide Dismutase from Staphylococcus equorum and S. saprophyticus.

    Science.gov (United States)

    Retnoningrum, Debbie S; Rahayu, Anis Puji; Mulyanti, Dina; Dita, Astrid; Valerius, Oliver; Ismaya, Wangsa T

    2016-04-01

    A recombinant hybrid of manganese dependent-superoxide dismutase of Staphylococcus equorum and S. saprophyticus has successfully been overexpressed in Escherichia coli BL21(DE3), purified, and characterized. The recombinant enzyme suffered from degradation and aggregation upon storage at -20 °C, but not at room temperature nor in cold. Chromatographic analysis in a size exclusion column suggested the occurrence of dimeric form, which has been reported to contribute in maintaining the stability of the enzyme. Effect of monovalent (Na(+), K(+)), divalent (Ca(2+), Mg(2+)), multivalent (Mn(2+/4+), Zn(2+/4+)) cations and anions (Cl(-), SO4 (2-)) to the enzyme stability or dimeric state depended on type of cation or anion, its concentration, and pH. However, tremendous effect was observed with 50 mM ZnSO4, in which thermostability of both the dimer and monomer was increased. Similar situation was not observed with MnSO4, and its presence was detrimental at 200 mM. Finally, chelating agent appeared to destabilize the dimer around neutral pH and dissociate it at basic pH. The monomer remained stable upon addition of ethylene diamine tetraacetic acid. Here we reported unique characteristics and stability of manganese dependent-superoxide dismutase from S. equorum/saprophyticus. PMID:26960678

  20. Characterization of Mobile Staphylococcus equorum Plasmids Isolated from Fermented Seafood That Confer Lincomycin Resistance.

    Directory of Open Access Journals (Sweden)

    Jong-Hoon Lee

    Full Text Available The complete nucleotide sequences of lincomycin-resistance gene (lnuA-containing plasmids in Staphylococcus equorum strains isolated from the high-salt-fermented seafood jeotgal were determined. These plasmids, designated pSELNU1-3, are 2638-bp long, have two polymorphic sites, and encode typical elements found in plasmids that replicate via a rolling-circle mechanism including the replication protein gene (rep, a double-stranded origin of replication, a single-stranded origin of replication, and counter-transcribed RNA sequence, as well as lnuA. Plasmid sequences exhibit over 83% identity to other Staphylococcus plasmids that harbor rep and lnuA genes. Further, three pairs of identified direct repeats may be involved in inter-plasmid recombination. One plasmid, pSELNU1, was successfully transferred to other Staphylococcus species, Enterococcus faecalis, and Tetragenococcus halophilus in vitro. Antibiotic susceptibility of the transconjugants was host-dependent, and transconjugants maintained a lincomycin resistance phenotype in the absence of selective pressure over 60 generations.

  1. Characterization of Mobile Staphylococcus equorum Plasmids Isolated from Fermented Seafood That Confer Lincomycin Resistance.

    Science.gov (United States)

    Lee, Jong-Hoon; Jeong, Do-Won

    2015-01-01

    The complete nucleotide sequences of lincomycin-resistance gene (lnuA)-containing plasmids in Staphylococcus equorum strains isolated from the high-salt-fermented seafood jeotgal were determined. These plasmids, designated pSELNU1-3, are 2638-bp long, have two polymorphic sites, and encode typical elements found in plasmids that replicate via a rolling-circle mechanism including the replication protein gene (rep), a double-stranded origin of replication, a single-stranded origin of replication, and counter-transcribed RNA sequence, as well as lnuA. Plasmid sequences exhibit over 83% identity to other Staphylococcus plasmids that harbor rep and lnuA genes. Further, three pairs of identified direct repeats may be involved in inter-plasmid recombination. One plasmid, pSELNU1, was successfully transferred to other Staphylococcus species, Enterococcus faecalis, and Tetragenococcus halophilus in vitro. Antibiotic susceptibility of the transconjugants was host-dependent, and transconjugants maintained a lincomycin resistance phenotype in the absence of selective pressure over 60 generations. PMID:26448648

  2. Anthelmintic resistance in Swedish sheep flocks based on a comparison of the results from the faecal egg count reduction test and resistant allele frequencies of the beta-tubulin gene.

    Science.gov (United States)

    Höglund, Johan; Gustafsson, Katarina; Ljungström, Britt-Louise; Engström, Annie; Donnan, Alison; Skuce, Philip

    2009-04-01

    A faecal egg count reduction test (FECRT) survey was conducted during the grazing season 2006 and 2007 to provide an updated indication of the prevalence of anthelmintic resistance in sheep flocks in Sweden. A total of 1330 faecal samples from 90 flocks on 45 farms, with a minimum of 20 ewes each, was collected by local sheep veterinarians. Per treatment group, approximately 15 lambs were dewormed either with oral suspensions of ivermectin (Ivomec vet.) or albendazole (Valbazen vet.). The efficacy on each farm was investigated either in 2006 or 2007 by faecal egg counts collected on the day of treatment and in a new sample from the same animals 7-10 days later. Third-stage larvae (L3) were initially identified morphologically from pooled cultures. These were then used as the source of genomic DNA template for two molecular tests. The first was a PCR-based test for specific identification of Haemonchus contortus, and the second was a Pyrosequencing assay for the analysis of benzimidazole (BZ) resistance targeting the P200 mutation in the parasite's beta-tubulin gene. Larval cultures indicated that Teladorsagia and Trichostrongylus were the predominant genera, but Haemonchus was diagnosed in 37% of the flocks. The PCR results revealed an almost 100% agreement with those farms that had previously been shown to have Haemonchus present, even when the % prevalence was low (approximately 3%). Only two (4%) of the surveyed farms showed evidence of BZ-resistant worm populations, with H. contortus being the species implicated according to post-treatment larval culture results. The Pyrosequencing assay detected BZ resistant allele frequencies of >40% in the Haemonchus-positive farms and 100% resistant alleles in the clinically most resistant farms. These preliminary results suggest that the FECRT is less sensitive than the molecular test at detecting BZ resistance. However, both tests need to be interpreted carefully, bearing in mind the relative proportions of species

  3. RESISTÊNCIA ANTI-HELMÍNTICA EM REBANHOS OVINOS DA REGIÃO DA ASSOCIAÇÃO DOS MUNICÍPIOS DO ALTO IRANI (AMAI, OESTE DE SANTA CATARINA ANTHELMINTIC RESISTANCE ON SHEEP FLOCKS FROM ASSOCIATION OF THE MUNICIPALITIES OF THE ALTO IRANI REGION (AMAI, WEST OF SANTA CATARINA STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Ingrid Kelly Zanchet

    2007-09-01

    Full Text Available

    Para conhecer a situação da resistência anti-hel-míntica em ovinos de propriedades localizadas nos mu-nicípios da Associação dos Municípios do Alto Irani (AMAI, oeste de Santa Catarina, Brasil, foram avalia-dos nove rebanhos pelo teste de redução da OPG (ovos por grama de fezes. Este teste consiste na comparação da média da OPG de um grupo de animais quatorze dias após o tratamento com a média de um grupo controle não-medicado. Consideraram-se efetivas as drogas capazes de reduzir a OPG em 95%. Os princípios ativos utilizados foram: levamisol (7,5 mg/kg, closantel (7,5 mg/Kg, al-bendazol (10 e 5 mg/Kg, ivermectin e moxidectin (0,2 mg/Kg. Detectou-se resistência dos nematódeos gastrin-testinais a todos os grupos anti-helmínticos testados, sen-do que 100% das propriedades apresentam resistência ao ivermectin; 66,7% ao moxidectin, 44,4% ao levamisol e 75% aos benzimidazóis. Para as lactonas macrocíclicas e benzimidazóis, tanto o gênero Haemonchus sp. quanto Trichostrongylus sp. apresentaram resistência. Para o le-vamisol, a resistência está restrita a Trichostrongylus sp. Também foi detectada a presença de uma população de Haemonchus sp. resistente ao closantel e uma de Nema-todirus sp. resistente ao albendazol. Estes dados mostram a urgência de difundir medidas de controle integrado de parasitoses, visando prolongar a vida  útil dos princípios ativos ainda disponíveis para uso.

    PALAVRAS-CHAVES: Ovinos, resistência anti-helmíntica, Santa Catarina.

    In order to know the situation of the anthelmintic resistance in sheep farms in the municipalities of Asso-ciation of the municipalities of the High Irani Region - AMAI, West of Santa Catarina State, Brazil, nine flocks were submitted to the faecal egg counts reduction test (FECRT. This test consists in comparing the mean FEC of a group of sheep, 14 days after treatment with the mean FEC of a non-treated control group. Only drugs that could

  4. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds

    DEFF Research Database (Denmark)

    Holm, Signe A.; Sørensen, Camilla; Thamsborg, Stig M.;

    2014-01-01

    the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg) or fenbendazole (10.0 mg/kg). AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion...

  5. Jälle need ussid / Reet Lätti

    Index Scriptorium Estoniae

    Lätti, Reet, 1983-

    2012-01-01

    Hobustel esinevad parasiitide - askariidid e varsasolkmed (Parascaris equorum), väikesed ümarussid (Cyathostominae), suured strongüliidid (Strongylus vulgaris, S. edentatus), väikesed ümarussid (Strongyloides westeri), paeluss (Anoplocephala perfoliata) - tõrjest ning nakatumise kontrollimisest

  6. Anthelmintic resistance in Northern Ireland. II: Variations in nematode control practices between lowland and upland sheep flocks.

    Science.gov (United States)

    McMahon, C; Barley, J P; Edgar, H W J; Ellison, S E; Hanna, R E B; Malone, F E; Brennan, G P; Fairweather, I

    2013-02-18

    A questionnaire to obtain information on nematode control practices and sheep management was sent to over 1000 farmers in Northern Ireland. Replies were received from 305 flock owners, and data from 252 of them were analysed. Farms were divided into lowland and upland areas. Sizes of pasture and stocking rates on lowland and upland farms were 59.5 hectares, 6.99 sheep/hectare and 62.9 hectares and 10.01 sheep/hectare, respectively. Mean drenching rates for lambs and adults were 2.33 and 2.44, respectively, in lowland flocks and 2.73 and 2.71, respectively, in upland flocks. Between 2008 and 2011, the most frequently identified compounds in use were benzimidazoles and moxidectin in lowland flocks, and benzimidazoles and avermectins in upland flocks. Over the same period the most frequently identified commercial formulations were Tramazole(®), Panacur(®) and Allverm(®) (white drench), Levacide(®) (yellow drench), Oramec(®) (clear drench; avermectin), Cydectin(®) (clear drench; moxidectin) and Monepantel(®) (orange drench). Most respondents (56.35%) treated their lambs at weaning and the most common time to treat ewes was identified to be pre-mating (67.86% of respondents). The results of the questionnaire survey revealed that lowland annual drench frequency was 2.33 and 2.44 in lambs and ewes, respectively, although drench frequencies were higher in upland flocks: 2.73 and 2.71 for lambs and ewes, respectively. Annual drench rotation was practiced by 43.96% of flock owners, but whether this was true rotation or pseudo-rotation (i.e., substitution of one anthelmintic product by another product belonging to the same chemical group of anthelmintics) could not be explicitly determined. PMID:23228496

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

    Directory of Open Access Journals (Sweden)

    Fernanda Ramos

    2016-04-01

    Full Text Available 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 against multi-drug resistant gastrointestinal nematodes.

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

    Science.gov (United States)

    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 were effective against multi-drug resistant gastrointestinal nematodes. PMID:27054068

  9. Use of P-glycoprotein gene probes to investigate anthelmintic resistance in Haemonchus contortus and comparison with Onchocerca volvulus

    NARCIS (Netherlands)

    Kwa, M.S.G.; Okoli, M.N.; Schulz-Key, H.; Okongkwo, P.O.; Roos, M.H.

    1998-01-01

    A P-glycoprotein gene probe from the sheep parasitic nematode Haemonchus contortus was developed and used to analyse restriction fragment length polymorphisms between susceptible isolates and isolates resistant to either benzimidazole; levamisole and benzimidazole; or benzimidazole, ivermectin and c

  10. Eliminated chromatin of Ascaris contains a gene that encodes a putative ribosomal protein.

    OpenAIRE

    Etter, A; Aboutanos, M; Tobler, H; Müller, F.

    1991-01-01

    Chromatin diminution in the nematodes Parascaris equorum and Ascaris lumbricoides leads to the formation of somatic cells that contain less DNA than the germ-line cells. We present molecular evidence for the coding potential of germ-line-specific DNA. We report on a cDNA clone that codes for a putative ribosomal protein (ALEP-1, for A. lumbricoides eliminated protein 1). That the corresponding gene is located in the eliminated portion of the genome indicates a difference in germ-line and soma...

  11. Climatic influences on development and survival of free-living stages of equine strongyles: implications for worm control strategies and managing anthelmintic resistance.

    Science.gov (United States)

    Nielsen, Martin K; Kaplan, Ray M; Thamsborg, Stig M; Monrad, Jesper; Olsen, Susanne N

    2007-07-01

    Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, parasite control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a parasite population that is not exposed to anthelmintic treatment is described as being "in refugia" and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these parasites are not selected by treatment and so provide a pool of sensitive genes in the population. Accordingly, treatment should be avoided when pasture refugia are small because such treatments will place significant selection pressure for resistance on worm populations. Given this new paradigm for parasite control, it has become important to identify seasons and circumstances wherein refugia are diminished. Free-living stages of equine strongyles are highly dependent on climatic influences, and this review summarises studies of strongyle development and survival under laboratory and field conditions in Northern (cool) temperate, Southern (warm) temperate and subtropical/tropical climates. In Northern temperate climates, refugia are smallest during the winter. In contrast, refugia are lowest during the summer in warm temperate and subtropical/tropical climates. Although adverse seasonal changes clearly have significant effects on the ability of free living stages of strongyle nematode parasites to survive and develop, available data suggest that climatic influences cannot effectively "clean" pastures from one grazing season to the next. PMID:16815051

  12. Selection for anthelmintic resistant Teladorsagia circumcincta in pre-weaned lambs by treating their dams with long-acting moxidectin injection.

    Science.gov (United States)

    Leathwick, D M; Miller, C M; Fraser, K

    2015-12-01

    Administration of long-acting anthelmintics to pregnant ewes prior to lambing is a common practice in New Zealand. Today, most of these products contain macrocyclic lactone (ML) actives, which because of their lipophilic nature, are detectable in the milk of treated animals and in the plasma of their suckling offspring. This study was conducted to confirm the transfer of ML actives to lambs in the ewe's milk, and to assess whether this could result in selection for ML resistant nematodes in the lamb. Ninety, twin bearing Romney ewes were treated before lambing with a long-acting injectable formulation of moxidectin, a 100-day controlled release capsule (CRC) containing abamectin and albendazole, or remained untreated. After lambing, seven ewes from each treatment group were selected for uniformity of lambing date and, along with their twin lambs, relocated indoors. At intervals, all ewes and lambs were bled, and samples of ewe's milk were collected, for determination of drug concentrations. Commencing 4 weeks after birth all lambs were dosed weekly with 250 infective larvae (L3) of either an ML-susceptible or -resistant isolate of Teladorsagia circumcinta. At 12 weeks of age all lambs were slaughtered and their abomasa recovered for worm counts. Moxidectin was detected in the plasma of moxidectin-treated ewes until about 50 days after treatment and in their lambs until about day 60. Abamectin was detected in the plasma of CRC-treated ewes until the last sample on day 80 and in the plasma of their lambs until about day 60. Both actives were detectable in milk of treated ewes until day 80 after treatment. Establishment of resistant L3 was not different between the treatment groups but treatment of ewes with moxidectin reduced establishment of susceptible L3 by 70%, confirming the potential of drug transfer in milk to screen for ML-resistance in the suckling lamb. PMID:27120068

  13. Determining the Degree of Anthelmintic Resistance against Macrocyclic Lactones in Small Strongylus, Based on the Larvae Development Analysis (LDA in Horses from Grasslands in the Department of Casanare

    Directory of Open Access Journals (Sweden)

    Germán Alonso Prada

    2011-06-01

    Full Text Available This study was conducted in the grasslands of the Department of Casanare, seeking to determine the degree of anthelmintic susceptibility or resistance against macrocyclic lactones in small populations of Strongylus in this region of the country. Samples were taken from four municipalities in the department: Aguazul, Paz de Ariporo, Maní and El Yopal, between June, 2006 and April, 2007, where ten fresh fecal samples were collected in each municipality, directly from the field and in a completely random way. The samples were processed using the MacMaster coprological technique, thus determining the highest count of fecal epg by municipality. L3 larvae were extracted from each of the six samples with the highest count of fecal epg through the coprological and Baermann-Wetzel tests with which the Larvae Development Analysis (LDA test was run, detecting Small Strongylus highly susceptible to the action of macrocyclic lactones (ivermectin.

  14. A single amino acid substitution in isozyme GST mu in Triclabendazole resistant Fasciola hepatica (Sligo strain) can substantially influence the manifestation of anthelmintic resistance.

    Science.gov (United States)

    Fernández, V; Estein, S; Ortiz, P; Luchessi, P; Solana, V; Solana, H

    2015-12-01

    The helminth parasite Fasciola hepatica causes fascioliasis in human and domestic ruminants. Economic losses due to this infection are estimated in U$S 2000-3000 million yearly. The most common method of control is the use of anthelmintic drugs. However, there is an increased concern about the growing appearance of F. hepatica resistance to Triclabendazole (TCBZ), an anthelmintic with activity over adult and young flukes. F. hepatica has eight Glutathione S-Transferase (GST) isozymes, which are enzymes involved in the detoxification of a wide range of substrates through chemical conjugation with glutathione. In the present work we identified and characterized the GST mu gene isolated from the TCBZ-susceptible and TCBZ-resistant F. hepatica strains. Total RNA was transcribed into cDNA by reverse transcription and a 657 bp amplicon corresponding to the GST mu gene was obtained. The comparative genetic analysis of the GST mu gene of the TCBZ susceptible strain (Cullompton) and TCBZ resistant strain (Sligo) showed three nucleotide changes and one amino acid change at position 143 in the GST mu isozyme of the TCBZ-resistant strain. These results have potential relevance as they contribute better understand the mechanisms that generate resistance to anthelmintics.

  15. PREVALENCE AND ANTHELMINTIC EFFICACY OF ABAMECTIN AGAINST GASTROINTESTINAL PARASITES IN HORSES

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    A. MAHFOOZ, M. Z. MASOOD, A. YOUSAF, N. AKHTAR AND M. A. ZAFAR

    2008-06-01

    Full Text Available The prevalence and anthelmintic efficacy of Abamectin against gastrointestinal parasites under field conditions in Faisalabad (Punjab, Pakistan was studied in 100 horses. The overall prevalence of gastrointestinal parasites was 75%, including Strongylus spp. (50%, Oxyuris equi (12%, Parascaris equorum (8% and mixed infection (5%. Among these naturally infected animals, 15 were selected. These horses were assigned to three groups on the basis of prevalent species of gastrointestinal parasites. Each group had five animals, comprising four treatment horses and a control horse. Abamectin was evaluated against these gastrointestinal parasites with a single shot at the dose rate of 0.2 mg/kg body weight administered through subcutaneous route which resulted in 98% reduction in faecal egg count after day 14 post-treatment. Non-treated horses remained positive for gastrointestinal parasites. No adverse reactions were observed during the experimental period. It was concluded that Abamectin is highly effective against gastrointestinal parasites in horses.

  16. Endoparasites of horses from the Formiga city, located in center-west region of the state of Minas Gerais, Brazil

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    Weslen Fabricio Pires Teixeira

    2014-12-01

    Full Text Available With the aim of studying the endoparasite fauna of horses from the Formiga city, located in center-west region of the state of Minas Gerais, 25 animals that were naturally infected with helminths were evaluated. By means of parasitological necropsies, different endoparasites were found. The subfamily Cyathostominae presented the highest incidence, followed by Trichostrongylus axei, Oxyuris equi, Triodontophorus serratus, Strongyloides westeri, Strongylus edentatus, Habronema muscae, Parascaris equorum, Probstmayria vivipara, Strongylus vulgaris, Gasterophilus nasalis, Anoplocephala magna and Anoplocephala perfoliata. In the present study, if the species Probstmayria vivipara was not considered in the prevalence, the frequency of Cyathostominae was equivalent to 94.85%. The results obtained in this study allowed us to detect and identify different species of helminths in horses, and confirmed the high incidence of nematodes belonging to the subfamily Cyathostominae in the center-west region of Minas Gerais.

  17. Incidence of gastro-intestinal parasites in horses of Shimoga region, Karnataka state.

    Science.gov (United States)

    Adeppa, J; Ananda, K J; Krishna Murthy, C M; Satheesha, G M

    2016-09-01

    A study was conducted to ascertain the incidence of gastrointestinal parasites in horses of Shimoga region, to generate the data regarding status of parasitic infections of equines in Karnataka state due to paucity of information. A total of 100 fresh fecal samples of equines were collected and examined by direct and sedimentation method for the detection of parasitic egg/ova. Among 100 samples examined, 84 (84.0 %) were found positive for various gastrointestinal helminths. Out of 84 positive cases, 44 (52.38 %) were found positive for Strongylus spp. eggs, 09 (10.71 %) showed Parascaris equorum eggs, 06 (7.14 %) had Gastrodiscus spp. eggs, 04 (4.76 %) harbored Oxyuris equi and the remaining 21 (25.0 %) had a mixed infection of Strongylus spp., Strongyloides spp. and Gastrodiscus spp. PMID:27605810

  18. Functional Characterization of a Novel Class of Morantel-Sensitive Acetylcholine Receptors in Nematodes.

    Science.gov (United States)

    Courtot, Elise; Charvet, Claude L; Beech, Robin N; Harmache, Abdallah; Wolstenholme, Adrian J; Holden-Dye, Lindy; O'Connor, Vincent; Peineau, Nicolas; Woods, Debra J; Neveu, Cedric

    2015-12-01

    Acetylcholine receptors are pentameric ligand-gated channels involved in excitatory neuro-transmission in both vertebrates and invertebrates. In nematodes, they represent major targets for cholinergic agonist or antagonist anthelmintic drugs. Despite the large diversity of acetylcholine-receptor subunit genes present in nematodes, only a few receptor subtypes have been characterized so far. Interestingly, parasitic nematodes affecting human or animal health possess two closely related members of this gene family, acr-26 and acr-27 that are essentially absent in free-living or plant parasitic species. Using the pathogenic parasitic nematode of ruminants, Haemonchus contortus, as a model, we found that Hco-ACR-26 and Hco-ACR-27 are co-expressed in body muscle cells. We demonstrated that co-expression of Hco-ACR-26 and Hco-ACR-27 in Xenopus laevis oocytes led to the functional expression of an acetylcholine-receptor highly sensitive to the anthelmintics morantel and pyrantel. Importantly we also reported that ACR-26 and ACR-27, from the distantly related parasitic nematode of horses, Parascaris equorum, also formed a functional acetylcholine-receptor highly sensitive to these two drugs. In Caenorhabditis elegans, a free-living model nematode, we demonstrated that heterologous expression of the H. contortus and P. equorum receptors drastically increased its sensitivity to morantel and pyrantel, mirroring the pharmacological properties observed in Xenopus oocytes. Our results are the first to describe significant molecular determinants of a novel class of nematode body wall muscle AChR.

  19. Functional Characterization of a Novel Class of Morantel-Sensitive Acetylcholine Receptors in Nematodes.

    Directory of Open Access Journals (Sweden)

    Elise Courtot

    2015-12-01

    Full Text Available Acetylcholine receptors are pentameric ligand-gated channels involved in excitatory neuro-transmission in both vertebrates and invertebrates. In nematodes, they represent major targets for cholinergic agonist or antagonist anthelmintic drugs. Despite the large diversity of acetylcholine-receptor subunit genes present in nematodes, only a few receptor subtypes have been characterized so far. Interestingly, parasitic nematodes affecting human or animal health possess two closely related members of this gene family, acr-26 and acr-27 that are essentially absent in free-living or plant parasitic species. Using the pathogenic parasitic nematode of ruminants, Haemonchus contortus, as a model, we found that Hco-ACR-26 and Hco-ACR-27 are co-expressed in body muscle cells. We demonstrated that co-expression of Hco-ACR-26 and Hco-ACR-27 in Xenopus laevis oocytes led to the functional expression of an acetylcholine-receptor highly sensitive to the anthelmintics morantel and pyrantel. Importantly we also reported that ACR-26 and ACR-27, from the distantly related parasitic nematode of horses, Parascaris equorum, also formed a functional acetylcholine-receptor highly sensitive to these two drugs. In Caenorhabditis elegans, a free-living model nematode, we demonstrated that heterologous expression of the H. contortus and P. equorum receptors drastically increased its sensitivity to morantel and pyrantel, mirroring the pharmacological properties observed in Xenopus oocytes. Our results are the first to describe significant molecular determinants of a novel class of nematode body wall muscle AChR.

  20. Functional Characterization of a Novel Class of Morantel-Sensitive Acetylcholine Receptors in Nematodes.

    Science.gov (United States)

    Courtot, Elise; Charvet, Claude L; Beech, Robin N; Harmache, Abdallah; Wolstenholme, Adrian J; Holden-Dye, Lindy; O'Connor, Vincent; Peineau, Nicolas; Woods, Debra J; Neveu, Cedric

    2015-12-01

    Acetylcholine receptors are pentameric ligand-gated channels involved in excitatory neuro-transmission in both vertebrates and invertebrates. In nematodes, they represent major targets for cholinergic agonist or antagonist anthelmintic drugs. Despite the large diversity of acetylcholine-receptor subunit genes present in nematodes, only a few receptor subtypes have been characterized so far. Interestingly, parasitic nematodes affecting human or animal health possess two closely related members of this gene family, acr-26 and acr-27 that are essentially absent in free-living or plant parasitic species. Using the pathogenic parasitic nematode of ruminants, Haemonchus contortus, as a model, we found that Hco-ACR-26 and Hco-ACR-27 are co-expressed in body muscle cells. We demonstrated that co-expression of Hco-ACR-26 and Hco-ACR-27 in Xenopus laevis oocytes led to the functional expression of an acetylcholine-receptor highly sensitive to the anthelmintics morantel and pyrantel. Importantly we also reported that ACR-26 and ACR-27, from the distantly related parasitic nematode of horses, Parascaris equorum, also formed a functional acetylcholine-receptor highly sensitive to these two drugs. In Caenorhabditis elegans, a free-living model nematode, we demonstrated that heterologous expression of the H. contortus and P. equorum receptors drastically increased its sensitivity to morantel and pyrantel, mirroring the pharmacological properties observed in Xenopus oocytes. Our results are the first to describe significant molecular determinants of a novel class of nematode body wall muscle AChR. PMID:26625142

  1. Molecular and biochemical mining of heat-shock and 14-3-3 proteins in drug-induced protoscolices of Echinococcus granulosus and the detection of a candidate gene for anthelmintic resistance.

    Science.gov (United States)

    Pan, D; Das, S; Bera, A K; Bandyopadhyay, S; Bandyopadhyay, S; De, S; Rana, T; Das, S K; Suryanaryana, V V; Deb, J; Bhattacharya, D

    2011-06-01

    Cystic echinococcosis (CE) caused by the larval stage of Echinococcus granulosus is a disease that affects both humans and animals. In humans the disease is treated by surgery with a supplementary option of chemotherapy with a benzimidazole compound. During the present study heat-shock protein 60 (HSP 60) was identified as one of the most frequently expressed biomolecules by E. granulosus after albendazole treatment. Data were correlated with 14-3-3 protein signature, and overexpression of this molecule after albendazole induction was an indicator of cell survival and signal transduction during in vitro maintenance of E. granulosus for up to 72 h. This observation was further correlated with a uniform expression pattern of a housekeeping gene (actin II). Out of three β-tubulin gene isoforms of E. granulosus, β-tubulin gene isoform 2 showed a conserved point mutation indicative of benzimidazole resistance.

  2. Resistência parasitária em helmintos de eqüídeos e propostas de manejo Parasite resistance on helminths of equids and management proposal’s

    Directory of Open Access Journals (Sweden)

    Marcelo Beltrão Molento

    2005-12-01

    Full Text Available Os eqüinos apresentam uma grande variedade de parasitas em sua fauna helmíntica, e algumas espécies/gêneros são de relevada importância, como: Parascaris equorum, Anoplocephala perfoliata, Oxyuris equi, Cyathostomum spp. e Strongylus spp. O controle destas infecções depende principalmente da utilização de produtos antiparasitários de forma supressiva ou estratégica e, em menor escala, de forma curativa. O tratamento supressivo é o fator mais importante na promoção da seleção de organismos resistentes, prejudicando a sustentabilidade de qualquer programa sanitário. As formas de detecção da resistência parasitária são onerosas e as mais comuns expressam resultados imprecisos. Entretanto, estas técnicas servem para monitorar a evolução e determinar os organismos envolvidos. A combinação de drogas é uma ferramenta que deve ser utilizada com muita cautela, pois esta alternativa não garante uma redução significativa de organismos resistentes aos compostos envolvidos. O objetivo deste artigo é apresentar formas de planejamento que auxiliem a melhorar a condição sanitária, o bem-estar dos animais e preserve o efeito tóxico dos produtos antiparasitários.Equines harbour a variety of parasitic organisms on their helminth fauna and there are a few species/genus of interest, such as: Parascaris equorum, Anoplocephala perfoliata, Oxyuris equi, Cyathostomum spp. and Strongylus spp. The control of these infections relies mostly on the suppressive or strategic usage of antiparasitic compounds, and to a less extent on curative/salvage treatments. Suppressive treatment is the most important factor regarding the selection of resistant organisms, causing the impairment of sanitary programs. Detection methods of parasite resistance are expensive and the most common ones express variable results. Although, these techniques allow monitoring the evolution and the determination of which organisms are involved. Drug combination is a

  3. Duplex quantitative real-time PCR assay for the detection and discrimination of the eggs of Toxocara canis and Toxocara cati (Nematoda, Ascaridoidea in soil and fecal samples

    Directory of Open Access Journals (Sweden)

    Durant Jean-Francois

    2012-12-01

    Full Text Available Abstract Background Toxocarosis is a zoonotic disease caused by Toxocara canis (T. canis and/or Toxocara cati (T. cati, two worldwide distributed roundworms which are parasites of canids and felids, respectively. Infections of humans occur through ingestion of embryonated eggs of T. canis or T. cati, when playing with soils contaminated with dogs or cats feces. Accordingly, the assessment of potential contamination of these areas with these roundworms eggs is paramount. Methods A duplex quantitative real-time PCR (2qPCR targeting the ribosomal RNA gene internal transcribed spacer (ITS2 has been developed and used for rapid and specific identification of T. canis and T. cati eggs in fecal and soil samples. The assay was set up on DNA samples extracted from 53 adult worms including T. canis, T. cati, T. leonina, Ascaris suum (A. suum and Parascaris equorum (P. equorum. The assay was used to assess the presence of T. cati eggs in several samples, including 12 clean soil samples spiked with eggs of either T. cati or A. suum, 10 actual soil samples randomly collected from playgrounds in Brussels, and fecal samples from cats, dogs, and other animals. 2qPCR results on dogs and cats fecal samples were compared with results from microscopic examination. Results 2qPCR assay allowed specific detection of T. canis and T. cati, whether adult worms, eggs spiked in soil or fecal samples. The 2qPCR limit of detection (LOD in spiked soil samples was 2 eggs per g of soil for a turnaround time of 3 hours. A perfect concordance was observed between 2qPCR assay and microscopic examination on dogs and cats feces. Conclusion The newly developed 2qPCR assay can be useful for high throughput prospective or retrospective detection of T.canis and/or T. cati eggs in fecal samples as well as in soil samples from playgrounds, parks and sandpits.

  4. Parasitic infections detected by FLOTAC in zoo mammals from Warsaw, Poland.

    Science.gov (United States)

    Maesano, Gianpaolo; Capasso, Michele; Ianniello, Davide; Cringoli, Giuseppe; Rinaldi, Laura

    2014-06-01

    The aim of this study was to estimate the occurrence of intestinal parasites in groups of mammals kept in the Warsaw zoological garden (Poland). 71 pools of fecal samples were analyzed using the FLOTAC techniques. 48% of animals were positive and 47% of positivities showed multiple infections. Toxocara cati (71.4%) was found in felines; marsupials were infected with Coccidia (90%). Giardia spp. (24.0%), Blastocystis spp. (12.3%), Iodamoeba spp. (10.0%), Enterobius vermicularis (6.0%) and Entamoeba coli (3.3%) were found in primates. Gastrointestinal strongyles (60.5%) were prevalent in ruminants which resulted positive also to Coccidia (Eimeria spp. = 50.0%), Trichuris spp. (25.0%) and Nematodirus (14.0%). Strongyles (34.0%) were the most frequent parasites in monogastric herbivores, followed by Parascaris equorum (17.0%). None of the animals showed any symptom associated with gastrointestinal parasitic infections. According to our results the need to prevent, diagnose, control, and treat intestinal parasitism trough specific control programs is mandatory for animal welfare in order to limit the spread of parasitic infections in animals and humans. PMID:24827109

  5. Aneurysm of the cranial mesenteric artery as a site of carriage of Salmonella enterica subsp. enterica serovar Abortusequi in the horse.

    Science.gov (United States)

    Niwa, Hidekazu; Hobo, Seiji; Kinoshita, Yuta; Muranaka, Masanori; Ochi, Akihiro; Ueno, Takanori; Oku, Kazuomi; Hariu, Kazuhisa; Katayama, Yoshinari

    2016-07-01

    Salmonella enterica subsp. enterica serovar Abortusequi is a pathogen restricted to horses. Our investigation targeted 4 draft horses (9-10 months old) kept on a Japanese farm that had suffered an outbreak of S. Abortusequi abortion. The 4 horses were suspected to be carriers of the bacterium owing to their high agglutination titers (≥1:2,560) in tube agglutination testing. The owners' on-farm observations confirmed that the horses had no apparent abnormalities, and S. Abortusequi was not isolated from their blood, rectal swabs, or sternal bone marrow fluid at antemortem investigation. However, at autopsy, all horses displayed the following: suppurative aneurysm of the cranial mesenteric artery with heavy infection with Strongylus vulgaris larvae; heavy intestinal parasitic infection with Gasterophilus intestinalis, Parascaris equorum, Anoplocephala perfoliata, and S. vulgaris; and enlargement of the systemic lymph nodes. In each case, large numbers of S. Abortusequi were isolated from the anterior mesenteric artery thrombus. The thrombus isolates harbored a single virulence plasmid, and the pulsed-field gel electrophoresis profiles of the isolates were identical not only to each other but also to those of Japanese enzootic strains of S. Abortusequi. These results reveal that parasitic aneurysms of the cranial mesenteric artery should be considered an important possible site of carriage of S. Abortusequi in horses. The results also suggest high clonality of the isolated serovar in the horse population in Japan. PMID:27271985

  6. Prevalence, intensity and risk factors of infestation with major gastrointestinal nematodes in equines in and around Shashemane, Southern Ethiopia.

    Science.gov (United States)

    Seyoum, Zewdu; Tesfaye, Mulualem; Derso, Samuel

    2015-12-01

    Prevalence, intensity and risk factors of major gastrointestinal nematode infestation in equines were studied through a cross-sectional survey in 384 equids from October 2013 to April 2014 in and around Shashemane, southern Ethiopia. Three hundred and fifteen equids (82 %) were demonstrated harbouring one or more gastrointestinal (GIT) nematodes using the faecal flotation technique. The prevalence of GIT nematode infestation was 73.4, 85 and 86.5 % for horses, mules and donkeys, respectively. The identified nematodes were strongyle type (73.4 %), Parascaris equorum (21.4 %) and Oxyuris equi (4.4 %). Species of equines had a significant (χ (2) = 9.35, P nematode infestation. Donkeys were two times (OR = 2.3, 95 % CI 1.27-4.28, P nematode infestation than horses. Moreover, donkeys had the highest mean faecal egg counts (1831.2 egg per gram (EPG)) followed by mules (915.7 EPG) and horses (772.5 EPG). There was a significant association (P nematode infestation in equines. Moreover, suitable tropical climatic conditions, low level of management and owners' awareness, and poor animal health services are expected to contribute for high nematode infestation. Therefore, emphasis should be given to awareness creation about the strategic deworming, animal welfare and management.

  7. Innovative molecular diagnosis of Trichinella species based on β-carbonic anhydrase genomic sequence.

    Science.gov (United States)

    Zolfaghari Emameh, Reza; Kuuslahti, Marianne; Näreaho, Anu; Sukura, Antti; Parkkila, Seppo

    2016-03-01

    Trichinellosis is a helminthic infection where different species of Trichinella nematodes are the causative agents. Several molecular assays have been designed to aid diagnostics of trichinellosis. These assays are mostly complex and expensive. The genomes of Trichinella species contain certain parasite-specific genes, which can be detected by polymerase chain reaction (PCR) methods. We selected β-carbonic anhydrase (β-CA) gene as a target, because it is present in many parasites genomes but absent in vertebrates. We developed a novel β-CA gene-based method for detection of Trichinella larvae in biological samples. We first identified a β-CA protein sequence from Trichinella spiralis by bioinformatic tools using β-CAs from Caenorhabditis elegans and Drosophila melanogaster. Thereafter, 16 sets of designed primers were tested to detect β-CA genomic sequences from three species of Trichinella, including T. spiralis, Trichinella pseudospiralis and Trichinella nativa. Among all 16 sets of designed primers, the primer set No. 2 efficiently amplified β-CA genomic sequences from T. spiralis, T. pseudospiralis and T. nativa without any false-positive amplicons from other parasite samples including Toxoplasma gondii, Toxocara cati and Parascaris equorum. This robust and straightforward method could be useful for meat inspection in slaughterhouses, quality control by food authorities and medical laboratories. PMID:26639312

  8. DETECTING THE ALBENDAZOLUM ANTHELMINTIC RESISTANCE FOR NEMATODES IN DIGESTIVE CANAL OF SHEEP IN BASHANG ALTIPLANO AREA,HEBEI PROVINCE%河北省坝上地区绵羊消化道线虫对丙硫苯咪唑抗药性的检测

    Institute of Scientific and Technical Information of China (English)

    赵月兰; 冯雪领; 秦建华; 张华莹; 包永占; 崔平

    2004-01-01

    目的为了查明绵羊消化道线虫对丙硫苯咪唑的抗药性.方法应用粪便虫卵减少试验(FECRT)对河北省坝上地区绵羊消化道线虫的抗药性进行了检测.结果应用5mg/kg丙硫苯咪唑对5组绵羊进行驱虫的虫卵减少率分别为43.9%,38.46%,49.09%,37.63%和43.35%,驱净率分别为20%,15%,15%,25%和10%.结论根据FECRT 95%置信域小于90%,表明试验羊对该药有抗药性.

  9. 新疆阿勒泰富蕴县马自然感染消化道线虫情况初报%PRELIMINARY REPORT OF NATURAL INFECTION OF GASTROINTESTINAL NEMATODES IN HORSES IN FUYUN COUNTY, ALETAI CITY, XINJIANG UYGUR AUTONOMOUS REGION

    Institute of Scientific and Technical Information of China (English)

    图尔荪·萨迪尔; 卡丽比努尔·尔肯; 朱玉涛; 木合牙提·沙得别克; 恰布旦·阿仔拜; 巴音查汗

    2015-01-01

    In order to gather information on gastrointestinal nematode infection in house-raised and pasteurized horses, 74 fecal samples were randomly collected from horses in Fuyun County, Altay, Xinjiang Uygur Autonomous Region and examined using conventional parasitological method. Total infection rate was 94.59% (70/74) in the tested samples. The major parasite species (infection rates) were Strongylus equines (83.78%),Trichostrongylu (83.78%),Nematodirus spp (24.32%),Parascaris equorum (4.05%). These results could provided reference for the government to expel parasites in local horse and offer a basis for animal health work.%为了解新疆维吾尔自治区阿勒泰地区富蕴县马匹在舍饲和放牧2种饲养条件下感染的消化道线虫情况,随机采集样品74份,采用常规寄生虫病原学检查方法进行调查.调查结果显示,当地马总感染率为94.59%,主要感染的虫种为马圆线虫、毛线虫、细颈三齿线虫、马副蛔虫,感染率分别为83.78%、83.78%、24.32%、4.05%.本次调查数据可为当地马寄生虫病的计划性驱虫保健提供科学依据.

  10. Characterization of the Ca2+-gated and voltage-dependent K+-channel Slo-1 of nematodes and its interaction with emodepside.

    Science.gov (United States)

    Kulke, Daniel; von Samson-Himmelstjerna, Georg; Miltsch, Sandra M; Wolstenholme, Adrian J; Jex, Aaron R; Gasser, Robin B; Ballesteros, Cristina; Geary, Timothy G; Keiser, Jennifer; Townson, Simon; Harder, Achim; Krücken, Jürgen

    2014-12-01

    The cyclooctadepsipeptide emodepside and its parent compound PF1022A are broad-spectrum nematicidal drugs which are able to eliminate nematodes resistant to other anthelmintics. The mode of action of cyclooctadepsipeptides is only partially understood, but involves the latrophilin Lat-1 receptor and the voltage- and calcium-activated potassium channel Slo-1. Genetic evidence suggests that emodepside exerts its anthelmintic activity predominantly through Slo-1. Indeed, slo-1 deficient Caenorhabditis elegans strains are completely emodepside resistant. However, direct effects of emodepside on Slo-1 have not been reported and these channels have only been characterized for C. elegans and related Strongylida. Molecular and bioinformatic analyses identified full-length Slo-1 cDNAs of Ascaris suum, Parascaris equorum, Toxocara canis, Dirofilaria immitis, Brugia malayi, Onchocerca gutturosa and Strongyloides ratti. Two paralogs were identified in the trichocephalids Trichuris muris, Trichuris suis and Trichinella spiralis. Several splice variants encoding truncated channels were identified in Trichuris spp. Slo-1 channels of trichocephalids form a monophyletic group, showing that duplication occurred after the divergence of Enoplea and Chromadorea. To explore the function of a representative protein, C. elegans Slo-1a was expressed in Xenopus laevis oocytes and studied in electrophysiological (voltage-clamp) experiments. Incubation of oocytes with 1-10 µM emodepside caused significantly increased currents over a wide range of step potentials in the absence of experimentally increased intracellular Ca2+, suggesting that emodepside directly opens C. elegans Slo-1a. Emodepside wash-out did not reverse the effect and the Slo-1 inhibitor verruculogen was only effective when applied before, but not after, emodepside. The identification of several splice variants and paralogs in some parasitic nematodes suggests that there are substantial differences in channel properties among

  11. Characterization of the Ca2+-gated and voltage-dependent K+-channel Slo-1 of nematodes and its interaction with emodepside.

    Directory of Open Access Journals (Sweden)

    Daniel Kulke

    2014-12-01

    Full Text Available The cyclooctadepsipeptide emodepside and its parent compound PF1022A are broad-spectrum nematicidal drugs which are able to eliminate nematodes resistant to other anthelmintics. The mode of action of cyclooctadepsipeptides is only partially understood, but involves the latrophilin Lat-1 receptor and the voltage- and calcium-activated potassium channel Slo-1. Genetic evidence suggests that emodepside exerts its anthelmintic activity predominantly through Slo-1. Indeed, slo-1 deficient Caenorhabditis elegans strains are completely emodepside resistant. However, direct effects of emodepside on Slo-1 have not been reported and these channels have only been characterized for C. elegans and related Strongylida. Molecular and bioinformatic analyses identified full-length Slo-1 cDNAs of Ascaris suum, Parascaris equorum, Toxocara canis, Dirofilaria immitis, Brugia malayi, Onchocerca gutturosa and Strongyloides ratti. Two paralogs were identified in the trichocephalids Trichuris muris, Trichuris suis and Trichinella spiralis. Several splice variants encoding truncated channels were identified in Trichuris spp. Slo-1 channels of trichocephalids form a monophyletic group, showing that duplication occurred after the divergence of Enoplea and Chromadorea. To explore the function of a representative protein, C. elegans Slo-1a was expressed in Xenopus laevis oocytes and studied in electrophysiological (voltage-clamp experiments. Incubation of oocytes with 1-10 µM emodepside caused significantly increased currents over a wide range of step potentials in the absence of experimentally increased intracellular Ca2+, suggesting that emodepside directly opens C. elegans Slo-1a. Emodepside wash-out did not reverse the effect and the Slo-1 inhibitor verruculogen was only effective when applied before, but not after, emodepside. The identification of several splice variants and paralogs in some parasitic nematodes suggests that there are substantial differences in

  12. Anti-parasitic activity of pelleted sainfoin (Onobrychis viciifolia) against Ostertagia ostertagi and Cooperia oncophora in calves

    DEFF Research Database (Denmark)

    Desrues, O.; Pena-Espinoza, Miguel Angel; Hansen, T. V.;

    2016-01-01

    BACKGROUND: Increasing anthelmintic-resistance in nematodes of ruminants emphasises the need for sustainable parasite control. Condensed tannin-containing legume forages such as sainfoin (Onobrychis viciifolia) have shown promising anthelmintic properties in small ruminants but this has never been...

  13. The economic effects of whole-herd versus selective anthelmintic treatment strategies in dairy cows

    NARCIS (Netherlands)

    Charlier, J.; Levecke, B.; Devleesschauwer, B.; Vercruysse, J.; Hogeveen, Henk

    2012-01-01

    Current control practices against gastrointestinal nematodes in dairy cows rely strongly on anthelmintic use. To reduce the development of anthelmintic resistance or disposition of drug residues in the environment, novel control approaches are currently proposed that target anthelmintic treatment to

  14. Restrictions of anthelmintic usage

    DEFF Research Database (Denmark)

    Nielsen, Martin Krarup

    2009-01-01

    Given the increasing levels of anthelmintic resistance in equine parasites, parasitologists now recommend traditional treatment approaches to be abandoned and replaced by more sustainable strategies. It is of crucial importance to facilitate veterinary involvement to ensure that treatment decisio...

  15. Dicty_cDB: Contig-U13538-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 50764_1( AY350764 |pid:none) Parascaris univalens ribosomal pro... 95 2e-18 AE016817_243( AE016817 |pid:none...5e-17 EU125004_1( EU125004 |pid:none) Eurythoe complanata ribosomal prot... 91 5e-17 AY350763_1( AY350763 |pid:none) Parascaris

  16. AcEST: BP914944 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ntromere-associated protein OS=Parascaris univalens Align length 142 Score (bit) 48.1 E-value 2.0e-05 Report...nd centromere-associated protein OS=Parascaris univalens GN=PUMA1 PE=2 SV=1 Lengt

  17. AcEST: BP915100 [AcEST

    Lifescience Database Archive (English)

    Full Text Available t : Swiss-Prot sp_hit_id O61308 Definition sp|O61308|PUMA_PARUN 227 kDa spindle- and centromere-associated protein OS=Parascaris...dle- and centromere-associated protein OS=Parascaris univalens GN=PUMA1 PE=2 SV=1 Length = 1955 Score = 44.7

  18. Growth and aroma production by Staphylococcus xylosus, S- carnosus and S-equoum - a comparative study in model systems

    DEFF Research Database (Denmark)

    Søndergaard, A.K.; Stahnke, Louise Heller

    2002-01-01

    . equorum, S. xylosus and S. equorum formed more diacetyl, 2-butanone and acetoin and also more of the methyl-branched ketones arising from degradation of leucine, isoleucine and valine. S. carnosus produced more methyl-branched aldehydes, acids and corresponding esters from leucine, isoleucine and valine...

  19. Garlic exhibits lack of control over gastrointestinal nematodes in goats

    Science.gov (United States)

    Gastrointestinal nematodes (GIN) continue to hinder small ruminant production because of anthelmintic resistance and lack of effective products for GIN control in organic production. The objective of this study was to examine the effectiveness of a commercially available certified organic garlic pr...

  20. Detection and semi-quantification of Strongylus vulgaris DNA in equine faeces by real-time quantitative PCR

    DEFF Research Database (Denmark)

    Nielsen, Martin Krarup; Peterson, David S.; Monrad, Jesper;

    2008-01-01

    Strongylus vulgaris is an important strongyle nematode with high pathogenic potential infecting horses world-wide. Several decades of intensive anthelminitic use has virtually eliminated clinical disease caused by S. vulgaris, but has also causes high levels of anthelmintic resistance in equine...

  1. Standardization of the egg hatch test for the detection of benzimidazole resistance in parasitic nematodes

    NARCIS (Netherlands)

    Samson-Himmelstjerna, von G.; Coles, G.; Jackson, F.; Bauer, C.; Borgsteede, F.H.M.; Cirak, V.; Demeler, J.; Donnan, A.; Dorny, P.; Epe, C.; Harder, A.; Hoglund, J.; Kaminsky, R.; Kerboeuf, D.; Kuttler, U.; Papadopoulos, E.; Posedi, J.; Small, J.; Varady, M.; Verscruysse, J.; Wirtherle, N.

    2009-01-01

    The ability to reliably detect anthelmintic resistance is a crucial part of resistance management. If data between countries are to be compared, the same test should give the same results in each laboratory. As the egg hatch test for benzimidazole resistance is used for both research and surveys, th

  2. Haemonchus contortus as a paradigm and model to study anthelmintic drug resistance.

    Science.gov (United States)

    Gilleard, John S

    2013-10-01

    Anthelmintic resistance is a major problem for the control livestock parasites and a potential threat to the sustainability of community-wide treatment programmes being used to control human parasites in the developing world. Anthelmintic resistance is essentially a complex quantitative trait in which multiple mutations contribute to the resistance phenotype in an additive manner. Consequently, a combination of forward genetic and genomic approaches are needed to identify the causal mutations and quantify their contribution to the resistance phenotype. Therefore, there is a need to develop genetic and genomic approaches for key parasite species identified as relevant models. Haemonchus contortus, a gastro-intestinal parasite of sheep, has shown a remarkable propensity to develop resistance to all the drugs used in its control. Partly because of this, and partly because of its experimental amenability, research on this parasite has contributed more than any other to our understanding of anthelmintic resistance. H. contortus offers a variety of advantages as an experimental system including the ability to undertake genetic crosses; a prerequisite for genetic mapping. This review will discuss the current progress on developing H. contortus as a model system in which to study anthelmintic resistance. PMID:23998513

  3. Modelling nematode infections in sheep and parasite control strategies

    OpenAIRE

    Laurenson, Yan Christian Stephen Mountfort

    2012-01-01

    Gastrointestinal parasitism in grazing lambs adversely affects animal performance and welfare, causing significant production losses for the sheep industry. Control of gastrointestinal parasitism using chemotherapeutic treatment is under threat due to the emergence of anthelmintic resistance, thus stimulating research into alternative control strategies. Whilst investigating control strategies experimentally can be costly and time consuming, using a mathematical modelling appro...

  4. EVALUATION OF ANTHELMINTIC ACTIVITY OF PLUMBAGO ZEYLANICA LINN.

    OpenAIRE

    H.P. Desai*, M.D. Kapadia and A.R. Kharat

    2012-01-01

    Development of anthelmintic resistance and high cost of conventional anthelmintic drugs lead to the evaluation of medicinal plants which acts as an alternative source of anthelmintics. The present study has been undertaken to perform the evaluation of anthelmintic activity of Plumbago zeylanica belonging to family Plumbaginaceae. In the current study, experiments were conducted to evaluate the possible anthelminitic effects of various extracts of the roots of Plumbago zeylanica. Various conce...

  5. A preliminary proteomic characterisation of extracellular vesicles released by the ovine parasitic nematode, Teladorsagia circumcincta

    OpenAIRE

    Tzelos, Thomas; Matthews, Jacqueline B; Amy H Buck; Simbari, Fabio; Frew, David; Inglis, Neil F.; Mclean, Kevin; Nisbet, Alasdair J; Whitelaw, C. Bruce A.; Knox, David P.; Tom N. McNeilly

    2016-01-01

    Teladorsagia circumcincta is a major cause of ovine parasitic gastroenteritis in temperate climatic regions. The development of high levels of anthelmintic resistance in this nematode species challenges its future control. Recent research indicates that many parasite species release extracellular vesicles into their environment, many of which have been classified as endocytic in origin, termed exosomes. These vesicles are considered to play important roles in the intercellular communication b...

  6. The host immune response to gastrointestinal nematode infection in sheep

    OpenAIRE

    McRae, K. M.; Stear, M. J.; Good, B.; Keane, O. M.

    2015-01-01

    Summary Gastrointestinal nematode infection represents a major threat to the health, welfare and productivity of sheep populations worldwide. Infected lambs have a reduced ability to absorb nutrients from the gastrointestinal tract, resulting in morbidity and occasional mortality. The current chemo‐dominant approach to nematode control is considered unsustainable due to the increasing incidence of anthelmintic resistance. In addition, there is growing consumer demand for food products from an...

  7. Restrictions of anthelmintic usage: perspectives and potential consequences

    OpenAIRE

    Nielsen, Martin K

    2009-01-01

    Given the increasing levels of anthelmintic resistance in equine parasites, parasitologists now recommend traditional treatment approaches to be abandoned and replaced by more sustainable strategies. It is of crucial importance to facilitate veterinary involvement to ensure that treatment decisions are based on parasitic knowledge. Despite recommendations given for the past two decades, strategies based on the selective therapy principle have not yet been implemented on a larger scale in equi...

  8. Controlling internal parasites without anthelmintics (a review) OF0132

    OpenAIRE

    KEATINGE, Ray

    1996-01-01

    1.0 Executive summary 1. Internal parasites are a major source of economic loss in grazing ruminants. To a greater or lesser degree, most farms in the UK rely on anthelmintics for control. In most situations these products continue to be highly effective, but anthelmintic resistance is increasing to the limited range of products available, raising serious concerns over the future of worm control. 2. Internal parasites are also of concern on organic farms, where the prophylactic us...

  9. The effect of triflumuron (SIR8514) on the free-living stages of sheep nematodes.

    Science.gov (United States)

    Waller, P J; Lacey, E

    1986-06-01

    Studies both in vitro and in vivo showed that the insect growth regulator, triflumuron, exhibited potent larvacidal effects against the free-living stages of Trichostrongylus colubriformis. Effects were not as marked on the closely related nematodes, Haemonchus contortus and Ostertagia circumcincta. Nevertheless, these findings suggest that growth regulators may be used to develop novel methods of nematode control, and thus offer alternatives or adjuncts to conventional anthelmintic therapy and at the same time reduce the selection for anthelmintic resistance. PMID:3739204

  10. The emergence of resistance to the benzimidazole anthlemintics in parasitic nematodes of livestock is characterised by multiple independent hard and soft selective sweeps.

    Directory of Open Access Journals (Sweden)

    Elizabeth Redman

    2015-02-01

    Full Text Available Anthelmintic resistance is a major problem for the control of parasitic nematodes of livestock and of growing concern for human parasite control. However, there is little understanding of how resistance arises and spreads or of the "genetic signature" of selection for this group of important pathogens. We have investigated these questions in the system for which anthelmintic resistance is most advanced; benzimidazole resistance in the sheep parasites Haemonchus contortus and Teladorsagia circumcincta. Population genetic analysis with neutral microsatellite markers reveals that T. circumcincta has higher genetic diversity but lower genetic differentiation between farms than H. contortus in the UK. We propose that this is due to epidemiological differences between the two parasites resulting in greater seasonal bottlenecking of H. contortus. There is a remarkably high level of resistance haplotype diversity in both parasites compared with drug resistance studies in other eukaryotic systems. Our analysis suggests a minimum of four independent origins of resistance mutations on just seven farms for H. contortus, and even more for T. circumincta. Both hard and soft selective sweeps have occurred with striking differences between individual farms. The sweeps are generally softer for T. circumcincta than H. contortus, consistent with its higher level of genetic diversity and consequent greater availability of new mutations. We propose a model in which multiple independent resistance mutations recurrently arise and spread by migration to explain the widespread occurrence of resistance in these parasites. Finally, in spite of the complex haplotypic diversity, we show that selection can be detected at the target locus using simple measures of genetic diversity and departures from neutrality. This work has important implications for the application of genome-wide approaches to identify new anthelmintic resistance loci and the likelihood of anthelmintic

  11. Nematode parasites of animals are more prone to develop xenobiotic resistance than nematode parasites of plants

    Directory of Open Access Journals (Sweden)

    Silvestre A.

    2004-06-01

    Full Text Available In this paper, we concentrate on a comparison of plant and animal-parasitic nematodes, to gain insight into the factors that influence the acquisition of the drug resistance by nematodes. Comparing nematode parasite of domestic animals and cultivated plants, it appears that drug resistance threatens only domestic animal production. Does the paucity of report on nematicide field resistance reflect reality or, is nematicide resistance bypassed by other management practices, specific to cultivated plants (i.e. agricultural control ? First, it seems that selection pressure by treatments in plants is not as efficient as selection pressure in ruminants. Agronomic practices (i.e. sanitation, early planting, usage of nematodes resistant cultivar and crop rotation are frequently used to control parasitic-plant nematodes. Although the efficiency of such measures is generally moderate to high, integrated approaches are developing successfully in parasitic-plant nematode models. Secondly, the majority of anthelmintic resistance cases recorded in animal-parasitic nematodes concern drug families that are not used in plant-parasitic nematodes control (i.e. benzimidazoles, avermectines and levamisole. Thirdly, particular life traits of parasitic-plant nematodes (low to moderate fecundity and reproductive strategy are expected to reduce probability of appearance and transmission of drug resistance genes. It has been demonstrated that, for a large number of nematodes such as Meloidogyne spp., the mode of reproduction by mitotic parthenogenesis reduced genetic diversity of populations which may prevent a rapid drug resistance development. In conclusion, anthelmintic resistance develops in nematode parasite of animals as a consequence of an efficient selection pressure. Early detection of anthelmintic resistance is then crucial : it is not possible to avoid it, but only to delay its development in farm animal industry.

  12. Gastrointestinal parasites in Danish goats - prevalence and risk factors

    DEFF Research Database (Denmark)

    Sörensen, C.; Holm, S. A.; Thamsborg, S. M.;

    2012-01-01

    , and herds with a mean EPG>150 were offered a faecal egg count reduction test (FECRT). All herds were asked to complete a questionnaire about management and risk factors concerning parasites, particularly nematodes. Faecal egg counts were generally low; 2 out of 25 herds had a mean EPG>150. Herd prevalence......The aims were to examine prevalence of gastrointestinal parasites in Danish goats, based on faecal examination, in relation to geographical distribution and risk factors, and to investigate the occurrence of anthelmintic resistance in nematodes in selected farms. In April 2012 all Danish goat farms...

  13. The in vitro motility response to various anthelmintics of third-stage larvae of Oesophagostomum spp. from pigs.

    Science.gov (United States)

    Várady, M; Corba, J; Hrcková, G

    1998-07-01

    The in vitro activities of thiabendazole, levamisole, pyrantel, morantel and ivermectin against Oesophagostomum spp., the nodular worm of pigs, were determined and compared. The study was carried out using isolates of O. dentatum and O. quadrispinulatum, which had been defined in vivo. Infective larvae were exposed to the anthelmintics for 24 h and then placed in a micromotility meter. All the treatments significantly reduced the motility of the ensheathed L3 larvae, but the micromotility meter was not able to differentiate between anthelmintic resistant and anthelmintic susceptible isolates.

  14. Reduced field efficacy of ivermectin against Ostertagia ostertagi and Cooperia oncophora in Danish cattle

    DEFF Research Database (Denmark)

    Peña-Espinoza, Miguel; Drag, Markus; Hansen, Tina Vicky Alstrup;

    Field reports of anthelmintic resistance against the widely-used macrocyclic lactones (ML) in gastrointestinal nematodes (GIN) of cattle have appeared in NW-Europe in recent years. Objective: The aim of this study was to assess the efficacy of ivermectin (IVM) against field infections with GIN...... in larval cultures from treated groups in all six farms. At day 14 p.t. in treated animals, O. ostertagi L3 were found in 1 farm and C. oncophora L3 in 3 farms. On day 21 p.t., O. ostertagi L3 and C. oncophora L3 were detected in treated animals of 2 and 4 farms, respectively. Discussion: Reduced field...

  15. Resistance to benzimidazoles and levamisole in nematode parasites of sheep in Nyandarua district of Kenya

    DEFF Research Database (Denmark)

    Maingi, N.; Bjørn, H.; Gichohi, V.M.;

    1998-01-01

    The occurrence of anthelmintic resistance on 25 sheep farms in the Nyandarua District of Kenya was investigated, using the faecal egg count reduction test (FECRT), the egg hatch assay (EHA) and a larval development assay (LDA). In the FECRT, resistance to both benzimidazoles (BZs) and levamisole....... The LD50 values for TBZ in the LDA for four of the six isolates with BZ resistance in the FECRT were higher than 0.5 mu M (0.59-2.07) TBZ. There were disagreements in ascribing resistance for various farms, between methods of calculating and interpreting the faecal egg count reduction percentages (FECR...

  16. AcEST: BP919431 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ts) Value sp|Q7Z7B0|FLIP1_HUMAN Filamin-A-interacting protein 1 OS=Homo sa... 46 1e-04 sp|O61308|PUMA_PARUN ...E+ S+ +EC + E EK + L E+ V+ +R+ ELE SR Sbjct: 435 LEKLEEAFSKSKSECTQ-LHLNLEKEKNL------TKDLLNELEVVKSRVKELECSESR 486 >sp|O61308|PUMA..._PARUN 227 kDa spindle- and centromere-associated protein OS=Parascaris univalens GN=PUMA

  17. AcEST: DK961336 [AcEST

    Lifescience Database Archive (English)

    Full Text Available .. 37 0.069 sp|Q9PW73|SOJO_XENLA Cytoskeletal protein Sojo OS=Xenopus laevis... 37 0.090 sp|O61308|PUMA_PARU...LEAKADAQENALRTTEDQLEHSRHILAEKERILQMFKDEMKAL 215 Query: 546 KEEL 557 KEEL Sbjct: 216 KEEL 219 >sp|O61308|PUMA..._PARUN 227 kDa spindle- and centromere-associated protein OS=Parascaris univalens GN=PUMA1 PE=2 SV=1 Length

  18. AcEST: DK947480 [AcEST

    Lifescience Database Archive (English)

    Full Text Available NDC80 OS=Cand... 32 2.6 sp|O61308|PUMA_PARUN 227 kDa spindle- and centromere-associated ... 32 3.3 sp|P40460...LVKFQKYVDSMKAKSEEWPIKLSKIEDELNEKKENIKLITEEISQIQDSLQRKGLS 438 Query: 289 EEQ 297 EQ Sbjct: 439 VEQ 441 >sp|O61308|PUMA..._PARUN 227 kDa spindle- and centromere-associated protein OS=Parascaris univalens GN=PUMA

  19. Activity of autoinducer two (AI-2) in bacteria isolated from surface ripened cheeses

    DEFF Research Database (Denmark)

    Gori, Klaus; Jespersen, Lene

    ). Corynebacterium casei, Microbacterium barkeri, Microbacterium gubbeenense and S. equorum subsp. linens (all isolated from the smear of surface ripened cheeses) using the AI-2 bioluminescence assay. This indicates that AI-2 signaling could take place between bacteria found in the smear of surface ripened cheeses....

  20. Activity of autoinducer two (AI-2) in bacteria isolated from surface ripened cheeses

    DEFF Research Database (Denmark)

    Gori, Klaus; Jespersen, Lene

    2007-01-01

    ). Corynebacterium casei, Microbacterium barkeri, Microbacterium gubbeenense and S. equorum subsp. linens (all isolated from the smear of surface ripened cheeses) using the AI-2 bioluminescence assay. This indicates that AI-2 signaling could take place between bacteria found in the smear of surface ripened cheeses....

  1. Anthelmintic efficacy in captive wild impala antelope (Aepyceros melampus) in Lusaka, Zambia.

    Science.gov (United States)

    Nalubamba, King S; Mudenda, Ntombi B

    2012-05-25

    There has been an increase in the number of wild ungulates kept in captivity for ecotourism and conservation in Zambia and these animals are susceptible to a number of diseases including gastrointestinal helminth infections. Surveys to determine anthelmintic efficacy to gastrointestinal nematodes in captive-wildlife are not common and there have been no reports of anthelmintic resistance in captive-wildlife in Zambia. This study was carried out to determine the efficacy of the benzimidazole anthelmintic fenbendazole in captive wild impala (Aepyceros melampus) in Zambia. During the month of April 2011, at the end of the rainy season, the faecal egg count reduction test was performed at a private game facility for assessing anthelmintic efficacy of oral fenbendazole and the anthelmintic treatment showed an efficacy of 90%. Haemonchus spp. and Trichostrongylus spp. were the predominant genera present before treatment, but Haemonchus spp. larvae were the only genus recovered from the faecal cultures after anthelmintic treatment. This represents the first documentation of anthelmintic treatment failure in captive wild-antelopes in Zambia. It also demonstrated the ineffectiveness of the common traditional practice of deworming captive-wild antelopes at the end of the rainy season due to the rapid re-infection of impala that occurs due to high pasture infectivity. Suggestions on changes to current anthelmintic use/practices that will make them more efficacious and reduce the possibility of development of anthelmintic resistance in captive wild game in Zambia are also made.

  2. Sustainable helminth control of ruminants in developing countries.

    Science.gov (United States)

    Waller, P J

    1997-07-31

    Widespread anthelmintic resistance, at least amongst the important nematode parasites of small ruminants, threatens the sustainability of these livestock industries throughout both the developed and developing world. The exacerbation of this problem over the last decade or so, has provided the impetus for research into non-chemotherapeutic parasite control alternatives, such as host genetic resistance, grazing management, worm vaccines and biological control. Although some of these options provide practical benefits if currently adopted, or exciting prospects for the future, collectively they are unlikely to dispense with the need for the timely intervention of effective anthelmintic treatment. The issue of sustainability of helminth control practices therefore rests with the preservation of anthelmintic effectiveness through the implementation of principles of integrated pest management. Herein lies the difficulty-putting the principles into practice. Much of the research into sustainable nematode parasite control of ruminants has been done in the developed rather than the developing world, and the efforts to transfer this information to livestock owners has also been commensurately greater in the former. However the need for research and technology transfer is much more urgent in the developing world because of the lack of scientific and financial resources, the greater dependence on livestock industries and the much greater severity of the problem of anthelmintic resistance. This will require a major philosophical change in the affluent western world to the funding of national and international aid organisations who are largely responsible for these activities.

  3. Benzimidazole resistance in equine cyathostomes in Slovakia.

    Science.gov (United States)

    Várady, M; Königová, A; Corba, J

    2000-12-20

    The present study included 19 stud farms, including 243 horses, that were investigated for the occurrence of anthelmintic resistant cyathostomes. The number of horses on the farms varied from nine to more than 100, and horses of all ages were included. A minimum of seven horses were used for faecal egg count reduction (FECR) tests. The anthelmintics included were: fenbendazole (paste formulation), ivermectin (paste formulation) and pyrantel (powder). Resistance to benzimidazoles was detected on 14 farms, with FECR values ranging from 65.1 to 86.3%. Larval cultures after fenbendazole treatment revealed exclusively cyathostome larvae. Ivermectin was tested on eight farms and proved to be effective on all. Pyrantel was tested on two farms and FECR test indicated high efficacy (92-97%). Egg hatch assay (EHA) results showed that mean concentrations of thiabendazole that inhibited hatching in 50% of the eggs (ED(50)) in resistant populations were over 0.1 microg ml(-1). The results of our study suggest widespread resistance to fenbendazole in equine cyathostomes in Slovakia, and possible strategies to delay anthelmintic resistance are discussed briefly.

  4. Safety assessment of coagulase-negative staphylococci used in food production

    OpenAIRE

    Seitter, Marion

    2015-01-01

    Coagulase-negative staphylococci (CNS) are used in starter cultures for the production of fermented meat products due to their involvement in the development of desired red color, characteristic flavor as well as ensuring stability. But also other CNS species like S. condimenti, S. piscifermentans, S. equorum and S. succinus have a potential for future use in starter cultures. The safety of fermented food products is principally proven by long-term experience as traditional methods are consid...

  5. The efficacy of a slow-release albendazole capsule against Haemonchus contortus with known resistance to albendazole

    Directory of Open Access Journals (Sweden)

    Alan D. Fisher

    2013-02-01

    Full Text Available Controlled-release albendazole capsules (CRCs are currently registered for use in Australia and New Zealand as anthelmintic treatment in sheep. However, reports on the efficacy of such products on resistant parasite populations are sometimes controversial. This is the first study to report on the efficacy of such products under South African field conditions in sheep harbouring a population of Haemonchus contortus with known multiple anthelmintic resistance, including to albendazole. Treatment groups were comprised of CRC-treated and single dose albendazole-treated sheep, as well as negative controls. Groups were compared by using faecal egg count reduction tests, FAMACHA© anaemia scoring, conception rates and comparative weight gains over three and a half months. Based on a comparison of faecal egg counts, no advantage could be found using CRCs. Moreover, the use of the product actually decreased weight gain when compared with the control group animals.

  6. Atypical (RIO) protein kinases from Haemonchus contortus--promise as new targets for nematocidal drugs.

    Science.gov (United States)

    Campbell, Bronwyn E; Boag, Peter R; Hofmann, Andreas; Cantacessi, Cinzia; Wang, Conan K; Taylor, Paul; Hu, Min; Sindhu, Zia-Ud-Din; Loukas, Alex; Sternberg, Paul W; Gasser, Robin B

    2011-01-01

    Almost nothing is known about atypical kinases in multicellular organisms, including parasites. Supported by information and data available for the free-living nematode, Caenorhabditis elegans, and other eukaryotes, the present article describes three RIO kinase genes, riok-1, riok-2 and riok-3, from Haemonchus contortus, one of the most important parasitic nematodes of small ruminants. Analyses of these genes and their products predict that they each play critical roles in the developmental pathways of parasitic nematodes. The findings of this review indicate prospects for functional studies of these genes in C. elegans (as a surrogate) and opportunities for the design of a novel class of nematode-specific inhibitors of RIO kinases. The latter aspect is of paramount importance, given the serious problems linked to anthelmintic resistance in parasitic nematode populations of livestock. PMID:21262337

  7. Serological diagnosis of Strongylus vulgaris infection: use of a recombinant protein

    DEFF Research Database (Denmark)

    Andersen, Ulla Vestergaard; Howe, Daniel K.; Olsen, Susanne Nautrup;

    infarction of intestinal segments. Developing anthelmintic resistance in equine parasites has put emphasis on less intensive treatment regimens to maintain efficacy of current anthelmintics. This has been associated with apparent re-emergence of S. vulgaris. Currently there are no methods for diagnosing......Strongyle parasites are ubiquitous in grazing horses, with cyathostomins being the most prevalent, but the large strongyles having larger clinical impact. Strongylus vulgaris is considered most pathogenic nematode, with migrating larvae causing verminous endarteritis and potentially ischaemic...... the pathogenic migrating larval stages of S. vulgaris ante mortem. A cDNA library was constructed from RNA extracted from migrating S. vulgaris larvae. Excretory-secretory antigens from S. vulgaris adult specimens were used to immunise a rat. Hyperimmune serum was used to immunoscreen the cDNA library...

  8. Performance of conventional pcr for screening for strongylus vulgaris on horse farms

    DEFF Research Database (Denmark)

    Nielsen, Marianne K.; Wøhlk, Chamilla B.M.; Petersen, Stig L.;

      Strongyle parasites are ubiquitous in grazing horses. Of these, the bloodworm Strongylus vulgaris is regarded most pathogenic. Increasing levels of anthelmintic resistance in strongyle parasites has lead to recommendations of decreased treatment intensities, and there is now a pronounced need...... for reliable tools for detection of parasite burdens in general and S. vulgaris in particular. The only method currently available is the larval culture, which is laborious and time-consuming, so veterinary practitioners most often pool samples from several horses together in one culture to save time...... the performance of pooled versus individual PCR for farm screening purposes. Fecal samples were obtained from 331 horses on 18 different farms. Farm size ranged from 6 to 56 horses, and horses aged between 2 months and 31 years. Larval cultures and individual PCRs were performed from all horses. In addition, PCR...

  9. The efficacy of 30% FENBENDAZOLE anthelmintic paste in cyathostominosis in horses

    Directory of Open Access Journals (Sweden)

    Corina Badea

    2015-06-01

    Full Text Available Horse cyathostominosis is a large intestine helminthosis caused by parasites belonging to the family Strongylidae, subfamily Cyathostominae. The cyathostomins (small strongyles represent a challenge for the parasitologists and animal owners due to the different ontogenesis, the high number of parasite species and their ability to develop anthelmintic resistance. The faeces were examined by flotation (Willis method and the infestation level was determined by McMaster method in day 0, 7 and 14 post treatments. The product Vanbendazol (30% fenbendazole had a 97.7% efficacy in the treated horses from Şofronea, Arad County, using the Faecal egg count reduction test (FECRT. Also were performed Presidente and Borgsteede relations and the anthelmintic efficacy was 98.2% for the both relations.

  10. EVALUATION OF ANTHELMINTIC ACTIVITY OF PLUMBAGO ZEYLANICA LINN.

    Directory of Open Access Journals (Sweden)

    H.P. Desai*, M.D. Kapadia and A.R. Kharat

    2012-11-01

    Full Text Available Development of anthelmintic resistance and high cost of conventional anthelmintic drugs lead to the evaluation of medicinal plants which acts as an alternative source of anthelmintics. The present study has been undertaken to perform the evaluation of anthelmintic activity of Plumbago zeylanica belonging to family Plumbaginaceae. In the current study, experiments were conducted to evaluate the possible anthelminitic effects of various extracts of the roots of Plumbago zeylanica. Various concentrations (5, 10, 15, 20mg/ml of water and methanol extracts were tested and results were expressed in terms of time for paralysis and time for death of worms. Piperazine citrate was taken as a reference standard drug.The anthelmintic activity was observed by gradually increasing the dose of extract. Methanolic extract of Plumbago zeylenica showed higher activity as compared to water extract.

  11. Current Status for Gastrointestinal Nematode Diagnosis in Small Ruminants: Where Are We and Where Are We Going?

    Directory of Open Access Journals (Sweden)

    Sarah Jane Margaret Preston

    2014-01-01

    Full Text Available Gastrointestinal nematode (GIN parasites pose a significant economic burden particularly in small ruminant production systems. Anthelmintic resistance is a serious concern to the effective control of GIN parasites and has fuelled the focus to design and promote sustainable control of practices of parasite control. Many facets of sustainable GIN parasite control programs rely on the ability to diagnose infection both qualitatively and quantitatively. Diagnostics are required to determine anthelmintic efficacies, for targeted treatment programs and selection of animals for parasite resistant breeding. This review describes much of the research investigated to date to improve the current diagnostic for the above practices which is based on counting the number of parasite eggs in faeces.

  12. Anti-parasitic activity of pelleted sainfoin (Onobrychis viciifolia) against Ostertagia ostertagi and Cooperia oncophora in calves

    DEFF Research Database (Denmark)

    Desrues, O.; Pena-Espinoza, Miguel Angel; Hansen, T. V.;

    2016-01-01

    ) or concentrate and grass-clover hay (Group CO; n = 6, two pens). After 16 days of adaptation, all animals were experimentally infected with 10,000 and 66,000 third-stage larvae of Ostertagia ostertagi and Cooperia oncophora, respectively. Egg excretion, blood parameters and bodyweights were recorded throughout...... nematodes corroborates results from studies with small ruminants and encourages further investigations of the use of this crop for control of cattle nematodes.......BACKGROUND: Increasing anthelmintic-resistance in nematodes of ruminants emphasises the need for sustainable parasite control. Condensed tannin-containing legume forages such as sainfoin (Onobrychis viciifolia) have shown promising anthelmintic properties in small ruminants but this has never been...

  13. Diagnosis, Treatment and Management of Haemonchus contortus in Small Ruminants.

    Science.gov (United States)

    Besier, R B; Kahn, L P; Sargison, N D; Van Wyk, J A

    2016-01-01

    Haemonchus contortus is a highly pathogenic, blood-feeding nematode of small ruminants, and a significant cause of mortalities worldwide. Haemonchosis is a particularly significant threat in tropical, subtropical and warm temperate regions, where warm and moist conditions favour the free-living stages, but periodic outbreaks occur more widely during periods of transient environmental favourability. The clinical diagnosis of haemonchosis is based mostly on the detection of anaemia in association with a characteristic epidemiological picture, and confirmed at postmortem by the finding of large numbers of H. contortus in the abomasum. The detection of impending haemonchosis relies chiefly on periodic monitoring for anaemia, including through the 'FAMACHA' conjunctival-colour index, or through faecal worm egg counts and other laboratory procedures. A range of anthelmintics for use against H. contortus is available, but in most endemic situations anthelmintic resistance significantly limits the available treatment options. Effective preventative programmes vary depending on environments and enterprise types, and according to the scale of the haemonchosis risk and the local epidemiology of infections, but should aim to prevent disease outbreaks while maintaining anthelmintic efficacy. Appropriate strategies include animal management programmes to avoid excessive H. contortus challenge, genetic and nutritional approaches to enhance resistance and resilience to infection, and the monitoring of H. contortus infection on an individual animal or flock basis. Specific strategies to manage anthelmintic resistance centre on the appropriate use of effective anthelmintics, and refugia-based treatment schedules. Alternative approaches, such as biological control, may also prove useful, and vaccination against H. contortus appears to have significant potential in control programmes. PMID:27238006

  14. Analysis of Constraints of Chemoprophylactic Control of Livestock Helminthosis in Kenya

    International Nuclear Information System (INIS)

    Three studies were carried out to find out how livestock anthelmintics are used in Kenya. Using questioners in the first study, 342 farms were surveyed. In the second study a survey on anthelmintic resistance was carried out in 42 farms comprising of small and large scale concerns. The third study was carried out on 9 commonly used anthelmintic brands sold in Kenya. These were brought from agrochemical shops and pharmacies with the aim of determining their pharmaceutical quality. The results indicated that, farmers were ignorant of good anthelmintic practice. They either under or overdose their livestock. Few farmers recognized the value of drenching suckling or weaned animals. A prevalence of 75% of anthelmintic resistance was recorded. This was mainly against levamisoles and benzimidazoles in sheep and goats. Resistance was associated with increased dosing rates on both smallholder and large-scale farms. An analysis of the pharmaceutical quality of the drugs showed that there were some substandard drugs available on the market. Four out of seven brand names claiming to contain levamisole had the concentration at a much lower level than claimed on the label. Indeed two products did not contain any trace of levamisole. One product supposed to contain mebendazole had a drug at a substandard level. Two products supposed to contain oxyclosanide had the drug concentration at a satisfactory level although one had the concentration ata much higher level. The concentration of levamisole in two substandard drugs varied significantly between different batch products. These varied from 0% to 73.6%-85.4% of the concentration shown on the labels

  15. Experiences with integrated concepts for the control of Haemonchus contortus in sheep and goats in the United States.

    Science.gov (United States)

    Terrill, Thomas H; Miller, James E; Burke, Joan M; Mosjidis, Jorge A; Kaplan, Ray M

    2012-05-01

    The generally warm, moist environmental conditions in the southern United States (U.S.) are ideal for survival and growth of the egg and larval stages of Haemonchus contortus and other gastrointestinal nematodes (GIN) of sheep and goats. Consequently, infection with GIN is the greatest threat to economic small ruminant production in this region. With anthelmintic resistance now reaching epidemic proportions in small ruminants in the U.S., non-chemical control alternatives are critically needed. The Southern Consortium for Small Ruminant Parasite Control (SCSRPC) was formed in response to this crisis and over the last decade has successfully validated the use of several novel control technologies, including FAMACHA(©) for the implementation of targeted selective treatments (TST), copper oxide wire particles (COWP), nematode-trapping fungi, and grazing or feeding hay of the high-tannin perennial legume sericea lespedeza [Lespedeza cuneata (Dum.-Cours. G. Don)]. Producer attitudes toward GIN control in the U.S. have been shifting away from exclusive dependence upon anthelmintics toward more sustainable, integrated systems of parasite control. Some novel control technologies have been readily adopted by producers in combination with appropriate diagnostic tools, such as FAMACHA(©). Others techniques are still being developed, and will be available for producer use as they are validated. Although new drugs will likely be available to U.S. goat and sheep producers in the future, these will also be subject to development of anthelmintic resistance. Therefore, the adoption and implementation of sustainable GIN control principles will remain important. With emerging markets for grass-fed or organic livestock, there will continue to be a critical need for research and outreach on development and on-farm application of integrated GIN control systems for small ruminants in the U.S. for the foreseeable future. PMID:22178411

  16. Diagnosis, Treatment and Management of Haemonchus contortus in Small Ruminants.

    Science.gov (United States)

    Besier, R B; Kahn, L P; Sargison, N D; Van Wyk, J A

    2016-01-01

    Haemonchus contortus is a highly pathogenic, blood-feeding nematode of small ruminants, and a significant cause of mortalities worldwide. Haemonchosis is a particularly significant threat in tropical, subtropical and warm temperate regions, where warm and moist conditions favour the free-living stages, but periodic outbreaks occur more widely during periods of transient environmental favourability. The clinical diagnosis of haemonchosis is based mostly on the detection of anaemia in association with a characteristic epidemiological picture, and confirmed at postmortem by the finding of large numbers of H. contortus in the abomasum. The detection of impending haemonchosis relies chiefly on periodic monitoring for anaemia, including through the 'FAMACHA' conjunctival-colour index, or through faecal worm egg counts and other laboratory procedures. A range of anthelmintics for use against H. contortus is available, but in most endemic situations anthelmintic resistance significantly limits the available treatment options. Effective preventative programmes vary depending on environments and enterprise types, and according to the scale of the haemonchosis risk and the local epidemiology of infections, but should aim to prevent disease outbreaks while maintaining anthelmintic efficacy. Appropriate strategies include animal management programmes to avoid excessive H. contortus challenge, genetic and nutritional approaches to enhance resistance and resilience to infection, and the monitoring of H. contortus infection on an individual animal or flock basis. Specific strategies to manage anthelmintic resistance centre on the appropriate use of effective anthelmintics, and refugia-based treatment schedules. Alternative approaches, such as biological control, may also prove useful, and vaccination against H. contortus appears to have significant potential in control programmes.

  17. Community dynamics of coagulase-negative staphylococci during spontaneous artisan-type meat fermentations differ between smoking and moulding treatments.

    Science.gov (United States)

    Janssens, M; Myter, N; De Vuyst, L; Leroy, F

    2013-08-16

    Coagulase-negative staphylococci (CNS) that are naturally present in the raw meat batter of fermented sausages or that originate from the addition of a starter culture play a role in flavour development. A wide species diversity of CNS can be present in fermented meats, but it is not fully clear yet how specific process parameters select for specific CNS by affecting their community dynamics. Therefore, the influence of smoking and moulding treatments on the CNS community dynamics in spontaneously fermented, artisan-type sausages was investigated. During the fermentation stage, the meat batter was in all cases dominated by Staphylococcus saprophyticus, in addition to Lactobacillus sakei as governing lactic acid bacterium. Following fermentation, the bacterial communities were not perturbed by the smoking treatment, since both L. sakei and S. saprophyticus remained dominant throughout the ripening stage and prevailed in the end-products. Yet, when fermentation was followed by a moulding step with Penicillium nalgiovense, a shift of the CNS communities towards dominance by Staphyloccocus equorum was seen, despite a similar evolution of L. sakei. This effect was possibly due to a pH rise caused by the mould, a hypothesis which was reinforced by the finding that the isolated strain S. equorum DBX-S-17 was more sensitive to low pH than the isolated strain S. saprophyticus DFL-S-12 during growth experiments in brain heart infusion (BHI). Differences in CNS communities may affect sausage flavour, due to intraspecies variations in metabolic conversions of, for instance, amino acids. The fact that 3-methyl-butanal was only found in the moulded sausage, which was dominated by S. equorum, may be related to the finding that the isolated strain of this species was able to produce this compound in BHI medium, whereas the isolated strain of S. saprophyticus was not.

  18. Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

    Directory of Open Access Journals (Sweden)

    Vatn Synnøve

    2011-05-01

    Full Text Available Abstract Background Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR, representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in Norway. Methods A questionnaire survey regarding worm control practices was performed in small ruminant flocks in Norway. Flocks were selected from the three main areas of small ruminant farming, i.e. the coastal, inland and northern areas. A total of 825 questionnaires, comprising 587 sheep flocks (return rate of 51.3% and 238 goat flocks (52.6% were included. Results The results indicated that visual appraisal of individual weight was the most common means of estimating the anthelmintic dose used in sheep (78.6% and goat (85.1% flocks. The mean yearly drenching rate in lambs and ewes were 2.5 ± 1.7 and 1.9 ± 1.1, respectively, whereas it was 1.0 (once a year in goats. However, these figures were higher in sheep in the coastal area with a rate of 3.4 and 2.2 in lambs and ewes, respectively. Benzimidazoles were the predominant anthelmintic class used in sheep flocks (64.9% in 2007, whereas benzimidazoles and macrocyclic lactones were both equally used in dairy goat flocks. In the period of 2005-2007, 46.3% of the sheep flocks never changed the anthelmintic class. The dose and move strategy was practiced in 33.2% of the sheep flocks. Conclusions The present study showed that inaccurate weight calculation gives a risk of under-dosing in over 90% of the sheep and goat flocks in Norway. Taken together with a high treatment frequency in lambs, a lack of anthelmintic class rotation and the common use of a dose-and-move strategy, a real danger for development of

  19. Benzimidazole-resistant gastrointestinal nematodes in indigenous Chiapas and Pelibuey sheep breeds from Chiapas, Mexico.

    Science.gov (United States)

    Liébano-Hernández, E; González-Olvera, M; Vázquez-Peláez, C; Mendoza-de-Gives, P; Ramírez-Vargas, G; Peralta-Lailson, M; Reyes-García, M E; Osorio, J; Sánchez-Pineda, H; López-Arellano, M E

    2015-01-01

    Because of the natural adaptation of Mexican sheep, the aim of the present study was to identify the presence or absence of gastrointestinal parasitic nematodes (GIN) resistant to benzimidazole (BZ) in both Chiapas and Pelibuey sheep breeds on local farms. Both male and female GIN-infected grazing sheep of the two breeds were selected. Sheep faecal samples were collected to obtain infective larvae (L3). This evolving stage of the parasite was used for taxonomic identification of the genus, based on its morphological characteristics. BZ anthelmintic resistance was evaluated using a nematode-compound in vitro interaction bioassay and the allele-specific polymerase chain reaction technique to detect mutations of residues 198 and 200 on isotype 1 of the β-tubulin gene. Three BZ-based compounds (febendazole (FBZ), tiabendazole (TBZ) and albendazole (ABZ)) at concentrations of 1, 0.5, 0.25, 0.125, 0.062 and 0.03 mg/ml were used to estimate the anthelmintic efficacy and lethal dose (LD50, LD90 and LD99) of the drugs. Two parasitic nematodes, Haemonchus and Teladorsagia, were identified in both isolates. Also, the proportions of anthelmintic resistance identified in GIN of the two sheep breeds were 68% in isolates from the Chiapas breed and 71.8% in the Pelibuey breed. The specific lethal activity obtained with FBZ was higher than 90%. However, TBZ and ABZ showed a lethal activity lower than 50%. High variability in the discriminating dose values was found among the BZ drugs. For example, FBZ LD ranged from 0.01 to 1.20 mg/ml; on the other hand, TBZ and ABZ required a dose ranging from 0.178 to 759 mg/ml. In addition, amino acid changes of Phe (TTC) to Tyr (TAC) at codon 200 of the β-tubulin gene, showing resistance to BZ, and no changes at codon 198 Glu (GAA) to Ala (GCA) were observed for both isolates. These results confirmed the presence of a genetic mutation associated with BZ in both Chiapas and Pelibuey nematode isolates.

  20. Field efficacy of four anthelmintics and confirmation of drug-resistant nematodes by controlled efficacy test and pyrosequencing on a sheep and goat farm in Denmark.

    Science.gov (United States)

    Peña-Espinoza, Miguel; Thamsborg, Stig M; Demeler, Janina; Enemark, Heidi L

    2014-12-15

    We describe a case of anthelmintic resistance on one of the largest organic small ruminant farms in Denmark. The flock was established in 2007 by purchase of animals from other Danish farms and had history of clinical parasitism, high mortality of young stock and anthelmintic treatment failure. In October 2011, 40 lambs and 40 kids were selected for a faecal egg count reduction test (FECRT) with fenbendazole (FBZ), ivermectin (IVM), moxidectin (MOX) and levamisole (LEV). Lambs were treated with the recommended sheep dose of each product while kids received the sheep dose of IVM, 1.5× sheep dose of MOX and 2× sheep dose of FBZ and LEV. Untreated lambs and kids were also included and three methods for calculating faecal egg count (FEC) reduction were compared. In a subsequent investigation, a controlled efficacy test (CET) with FBZ and IVM was performed in lambs infected with Haemonchus contortus and Trichostrongylus colubriformis isolated from adult goats on the farm. Recovered specimens of H. contortus were subjected to pyrosequencing for detection of single nucleotide polymorphisms (SNPs) related to benzimidazole (BZ) resistance. During the FECRT, FECs in untreated lambs dropped significantly by 47%. No FEC reduction was detected in untreated kids. After FBZ treatments, FEC reductions in lambs and kids ranged from 15 to 54% and 49-56%, respectively, according to the different calculation methods. Post IVM treatments, FEC reductions in lambs and kids varied between 71-90% and 81-83%, correspondingly. LEV and MOX reduced FECs by 98-100% in both species. In the CET, FBZ reduced H. contortus worm counts by 52-56% and no reduction in T. colubriformis counts were detected after treatment. IVM eliminated 100% of H. contortus and reduced T. colubriformis counts by 84-92%, according to different calculation methods. Pyrosequencing of isolated H. contortus revealed increased frequencies of the BZ resistance-related SNP in codon 200 of the β-tubulin isotype 1 gene

  1. Three-year evaluation of best practice guidelines for nematode control on commercial sheep farms in the UK.

    Science.gov (United States)

    Learmount, Jane; Stephens, Nathalie; Boughtflower, Valerie; Barrecheguren, Alba; Rickell, Kayleigh; Massei, Giovanna; Taylor, Mike

    2016-08-15

    Anthelmintics are commonly used on the majority of UK commercial sheep farms to reduce major economic losses associated with parasitic diseases. With increasing anthelmintic resistance worldwide, several countries have produced evidence-based, best practice guidelines with an example being the UK's Sustainable Control of Parasites in Sheep (SCOPS) initiative. In 2012, a pilot study demonstrated that SCOPS-managed farms used fewer anthelmintic treatments than traditionally managed farms, with no impact on lamb productivity and worm burden. Building on these results, we collected data for three consecutive years (2012-2014) with the following aims: (1) To compare the effects of traditional and SCOPS-based parasite management on lamb productivity and worm burden; (2) To evaluate the effect of region and farm type on lamb productivity and worm burden; (3) To compare the frequency and patterns of use of anthelmintic treatment on traditional and SCOPS-managed farms. The study was carried out on 16 farms located in the North east and the South west of England and Wales. Lamb productivity was assessed by quantifying birth, mid-season and finish weights and calculating daily live-weight gains and time to finish in a cohort of 40-50 lambs on each farm. Five annual faecal egg counts were carried out on each farm to assess worm burden. No differences in lamb productivity and worm burdens were found between farms that adopted SCOPS guidelines and traditional farms across the three years. However, mean infection levels increased for both the SCOPS and the traditional groups. Lamb production was not significantly different for farm type and region but the effect of region on infection was significant. For both ewes and lambs, SCOPS farms carried out significantly fewer anthelmintic treatments per year, and used fewer anthelmintic doses/animal than traditional farms. The data suggest a trend to increasing use of anthelmintics in ewes on traditional but not on the SCOPS farms and a

  2. Parasite management extension - challenging traditional practice through adoption of a systems approach.

    Science.gov (United States)

    Wilson, L; Rhodes, A P; Dodunski, G

    2015-11-01

    The drivers for anthelmintic use today are substantial and anthelmintic use has become an embedded normalised behaviour. The cheapness and easy availability of anthelmintic products has meant that New Zealand farmers have had access to easy "solutions" for dealing with parasites and minimal forward planning or system redesign has been required. Despite 30 years of messaging about the emerging issue of anthelmintic resistance, management to reduce parasitism and the need to change behaviour, farmer practice has largely remained unchanged. Traditional approaches to extension, particularly around parasite management, appear to have been quite ineffective, apart from encouraging change in anthelmintic products and a switch to use of anthelmintics in combination. More effective approaches are required. The evolving nature of anthelmintic resistance and sustainable management of parasitism require attitudes, knowledge and behaviour to change. This is a challenge for all players in the industry; researchers, manufacturers and sellers, advisors and farmers. Looking beyond agriculture to the health sector provides some insight into models of decision making and behaviour change that can inform future strategies. Features in the health belief model including concepts of self-efficacy and cues to action appear to align with the issues, challenges and culture prevailing in farming, and parasite management in particular. Programmes through which farmers have made substantial beneficial behaviour change and the lessons learnt are discussed. Effecting consistent behaviour change around parasite management will involve new approaches by all participants in the process. And the process itself also needs to change. It requires an understanding of whole-farm systems, and the consideration of all the sources of influence on the farmer and the other participants in the process. The process of knowledge sharing involving the farmer should be based on equality; each person in the process

  3. Genetic evidence for the spread of a benzimidazole resistance mutation across southern India from a single origin in the parasitic nematode Haemonchus contortus.

    Science.gov (United States)

    Chaudhry, Umer; Redman, Elizabeth M; Raman, Muthusamy; Gilleard, John S

    2015-09-01

    It is important to understand how anthelmintic drug resistance mutations arise and spread in order to determine appropriate mitigation strategies. We hypothesised that a molecular genetic study of Haemonchus contortus in southern India, a region where resistance may be less advanced than in western Europe and North America, might provide some important insights into the origin and spread of anthelmintic resistance. The F200Y (TAC) isotype-1 β-tubulin benzimidazole resistance mutation is common in H. contortus throughout the world and the F167Y (TAC) and E198A (GCA) mutations, although less common, have been reported in a number of different countries. We have investigated the haplotypic diversity and phylogenetic relationship of isotype-1 β-tubulin benzimidazole resistance alleles for 23 H. contortus populations from small ruminants across southern India. The F200Y (TAC) mutation was most common, being detected in 18/23 populations at frequencies between 9% and 84% and the E198A (GCA) mutation was also detected in 8/23 populations at frequencies between 8% and 18%. The F167Y (TAC) mutation was not detected in any of the 23 populations. Phylogenetic haplotype network analysis suggested that the F200Y (TAC) mutation has arisen multiple independent times in the region with at least three independent origins of resistance alleles across the populations surveyed. In contrast, the E198A (GCA) mutation was present on a single haplotype which, given the high level of haplotypic diversity of the susceptible alleles in the region, suggests this particular mutation has spread from a single origin, likely by anthropogenic animal movement. Population genetic analysis of 12 of the H. contortus populations, using a panel of eight microsatellite markers, revealed extremely low genetic differentiation between populations, consistent with the hypothesis of high gene flow among sites. Additionally, there was no significant genetic differentiation between H. contortus taken from

  4. Biodiversity and characterization of Staphylococcus species isolated from a small manufacturing dairy plant in Portugal.

    Science.gov (United States)

    Soares, José C; Marques, M Rosário; Tavaria, Freni K; Pereira, Joana O; Malcata, F Xavier; Pintado, Manuela M

    2011-03-30

    The level and the diversity of the staphylococcal community occurring in the environment and dairy products of a small manufacturing dairy plant were investigated. Species identification was performed using different molecular methods, viz. Multiplex-PCR, amplified ribosomal DNA restriction analysis (ARDRA), and sodA gene sequencing. The main species encountered corresponded to Staphylococcus equorum (41 isolates, 39.0%), S. saprophyticus (28 isolates, 26.7%) and S. epidermidis (15 isolates, 14.3%). Additionally, low incidence of enterotoxin genes was obtained, with only 9 strains (8.6%) being positive for one or more toxin genes. With regard to antimicrobial resistance, 57.1% of the isolates showed at least resistance against one antibiotic, and 28.6% were multi-resistant, which might accomplish resistance for up to 6 antibiotics simultaneously. These results provided evidence that the presence of Staphylococcus species in dairy environment are mostly represented by S. equorum and S. saprophyticus, and illustrate that carrying antimicrobial resistance genes has become reasonably widespread in cheese and dairy environment.

  5. Species of Staphylococcus and Bacillus isolated from traditional sausages as producers of biogenic amines.

    Directory of Open Access Journals (Sweden)

    Roberto eBermúdez

    2012-04-01

    Full Text Available Histidine, lysine, ornithine and tyrosine decarboxylase activities were tested in 38 strains of Staphylococcus (15 of Staph. equorum, 11 of Staph. epidermidis, 7 of Staph. saprophyticus, and 5 of Staph. pasteuri and 19 strains of Bacillus (13 of B. subtilis and 6 of B. amyloliquefaciens isolated from two Spanish traditional sausage varieties.The four decarboxylase activities were present in most of the strains studied, but some variability was observed between strains within each microbial species.Accumulation of putrescine and cadaverine was assessed in the culture media of the strains that displayed ornithine and lysine decarboxylase activities. The aminogenic potential of the strains was low, with amounts accumulated lower than 25 mg/L for the putrescine and than 5 mg/L for the cadaverine, with the exception of a strain of Staph. equorum that produced 1415 mg/L of putrescine, and of a strain of Staph. epidermidis that accumulated 977 mg/L of putrescine and 36 mg/L of cadaverine.

  6. Binding to extracellular matrix proteins and formation of biogenic amines by food-associated coagulase-negative staphylococci.

    Science.gov (United States)

    Seitter, Marion; Geng, Bettina; Hertel, Christian

    2011-02-28

    In connection with a study on the DNA microarray based detection of genes involved in safety and technologically relevant properties (Seitter (née Resch) et al., 2011), food-associated coagulase-negative staphylococci (CNS) were investigated phenotypically with regard to their ability to bind to the extracellular matrix proteins (ECM) and to produce biogenic amines. The properties have been shown to be involved in the colonization of injured tissue and invasion into host cells as well as in pharmacologic effects on humans, respectively. The CNS exhibited a low, but nevertheless clearly measurable ECM binding capacity, except for strains of Staphylococcus equorum and Staphylococcus succinus, which show a comparable or even higher binding to fibrinogen and fibronectin than that of the control strain Staphylococcus aureus Cowan. Formation of biogenic amines could be often detected in S. carnosus, S. condimenti and S. strains, but rarely in S. equorum and not in S. succinus and S. xylosus strains. Mostly, 2-phenylethylamine, tyramine and tryptamine were formed by resting cells in amounts 100 mg/l) of 2-phenylethylamine and putrescine. This study confirmed the need of consideration of ECM binding and biogenic amine formation in the safety assessment of CNS used in the production of fermented foods.

  7. Production trials involving use of the FAMACHA© system for haemonchosis in sheep : preliminary results

    Directory of Open Access Journals (Sweden)

    J.A. Van Wyk

    2008-09-01

    Full Text Available In three trials conducted on two separate farms the production of sheep treated for naturally acquired haemonchosis using the FAMACHA© system of targeted selective treatment (TST (i.e. to treat only those animals unable to manage unaided in the face of heavy Haemonchus challenge was compared to that of suppressively drenched sheep in the same flock. As expected by the research team who developed and evaluated the FAMACHA© system, TST did result in some loss in production. However, despite high levels of worm challenge in two of the trials and the fact that the comparison was with suppressive drenching which is not sustainable, the total effect was relatively small in relation to the important advantage of using the TST as regards reduced selection for anthelmintic resistance (AR. Concerning the sustainability of worm control, it is concluded that the development of drug resistance to anthelmintics leaves sheep and goat farmers in South Africa no choice but to use methods of TST such as FAMACHA©. The FAMACHA© system can also be a useful clinical aid for early on-farm detection of AR by farmers; the degree of improvement in the colour of the ocular mucous membrane from pale to red in individually drenched anaemic animals over a period of 7-14 days can give a good indication of the efficacy of the compound(s used.

  8. Automated parasite faecal egg counting using fluorescence labelling, smartphone image capture and computational image analysis.

    Science.gov (United States)

    Slusarewicz, Paul; Pagano, Stefanie; Mills, Christopher; Popa, Gabriel; Chow, K Martin; Mendenhall, Michael; Rodgers, David W; Nielsen, Martin K

    2016-07-01

    Intestinal parasites are a concern in veterinary medicine worldwide and for human health in the developing world. Infections are identified by microscopic visualisation of parasite eggs in faeces, which is time-consuming, requires technical expertise and is impractical for use on-site. For these reasons, recommendations for parasite surveillance are not widely adopted and parasite control is based on administration of rote prophylactic treatments with anthelmintic drugs. This approach is known to promote anthelmintic resistance, so there is a pronounced need for a convenient egg counting assay to promote good clinical practice. Using a fluorescent chitin-binding protein, we show that this structural carbohydrate is present and accessible in shells of ova of strongyle, ascarid, trichurid and coccidian parasites. Furthermore, we show that a cellular smartphone can be used as an inexpensive device to image fluorescent eggs and, by harnessing the computational power of the phone, to perform image analysis to count the eggs. Strongyle egg counts generated by the smartphone system had a significant linear correlation with manual McMaster counts (R(2)=0.98), but with a significantly lower coefficient of variation (P=0.0177). Furthermore, the system was capable of differentiating equine strongyle and ascarid eggs similar to the McMaster method, but with significantly lower coefficients of variation (Psmartphones as relatively sophisticated, inexpensive and portable medical diagnostic devices. PMID:27025771

  9. Serine/threonine phosphatases in socioeconomically important parasitic nematodes--prospects as novel drug targets?

    Science.gov (United States)

    Campbell, Bronwyn E; Hofmann, Andreas; McCluskey, Adam; Gasser, Robin B

    2011-01-01

    Little is known about the fundamental biology of parasitic nematodes (=roundworms) that cause serious diseases, affecting literally billions of animals and humans worldwide. Unlocking the biology of these neglected pathogens using modern technologies will yield crucial and profound knowledge of their molecular biology, and could lead to new treatment and control strategies. Supported by studies in the free-living nematode, Caenorhabditis elegans, some recent investigations have provided improved insights into selected protein phosphatases (PPs) of economically important parasitic nematodes (Strongylida). In the present article, we review this progress and assess the potential of serine/threonine phosphatase (STP) genes and/or their products as targets for new nematocidal drugs. Current information indicates that some small molecules, known to specifically inhibit PPs, might be developed as nematocides. For instance, some cantharidin analogues are known to display exquisite PP-inhibitor activity, which indicates that some of them could be designed and tailored to specifically inhibit selected STPs of nematodes. This information provides prospects for the discovery of an entirely novel class of nematocides, which is of paramount importance, given the serious problems linked to anthelmintic resistance in parasitic nematode populations of livestock, and has the potential to lead to significant biotechnological outcomes. PMID:20732402

  10. CONTROLE DE VERMINOSE EM EQUINOS NO NORTE DE MINAS GERAIS COM ASSOCIAÇÃO DE PAMOATO DE PIRANTEL E IVERMECTINA

    Directory of Open Access Journals (Sweden)

    Eduardo Robson Duarte

    2008-01-01

    Full Text Available In the North of Minas Gerais the equineculture is an important activity because it corroborates the success in the breeding of beef cattle. The equine verminosis control in this region has not been applied considering the anthelmintic resistances of nematodes and this resistance has been observed in some equine herds in Brazil. The present study has the objective to evaluate the effectiveness of pyrantel pamoate and ivermectin association in mare verminosis in the North of Minas Gerais, during the peripatum. After fourteen days of the first faecal egg count (FEC and treatment of the animals with these respective bases, the FEC reduction test indicated 98.1% effectiveness and the coprocultures were negative. After the worm identification from the control group, was observed 30% of filariod worms of Strongyloides spp., 30% of the genus Haemonchus, 20% were worms of Cyathosminae, 10% of the genus Trichostrongylgys and 10% of the genus Oesophagodontus. The results observed suggest that the use of pyrantel pamoate associated with ivermectin was safe during the peripartum and efficient in the FEC reduction of naturally infected mares raised in pastures of the North of Minas Gerais.

  11. Benzimidazole resistance in Haemonchus contortus recovered from farmed red deer.

    Science.gov (United States)

    Nagy, Gábor; Csivincsik, Ágnes; Zsolnai, Attila; Sugár, László

    2016-09-01

    Thirty Haemonchus contortus male worms were collected from farmed red deer yearlings in order to determine whether routine administration of albendazole for a long-term period (17 years) could select anthelmintic resistance. PCR-RFLP method based on single-nucleotide polymorphism of codon 200 in isotype 1 ß-tubulin gene (Phe200Tyr) was applied. The results showed a significant frequency of either the resistant allele (85 %) or the homozygous resistant genotype (70 %). By chi-square test, Hardy-Weinberg equilibrium of the population was accepted (p = 0.334, power of test 0.01). True prevalence of the resistant genotype (RR) was estimated to be 46.5-87.2 % (confidence interval 95 %) calculated by Sterne's exact method. These results confirmed that long-term use of benzimidazoles could change the relative allele frequency of genes associated with drug resistance and may cause a large-scale spread of the resistant allele. To our knowledge, this study supported benzimidazole resistance in Haemonchus contortus in red deer for the first time. PMID:27249966

  12. The host immune response to gastrointestinal nematode infection in sheep.

    Science.gov (United States)

    McRae, K M; Stear, M J; Good, B; Keane, O M

    2015-12-01

    Gastrointestinal nematode infection represents a major threat to the health, welfare and productivity of sheep populations worldwide. Infected lambs have a reduced ability to absorb nutrients from the gastrointestinal tract, resulting in morbidity and occasional mortality. The current chemo-dominant approach to nematode control is considered unsustainable due to the increasing incidence of anthelmintic resistance. In addition, there is growing consumer demand for food products from animals not subjected to chemical treatment. Future mechanisms of nematode control must rely on alternative, sustainable strategies such as vaccination or selective breeding of resistant animals. Such strategies take advantage of the host's natural immune response to nematodes. The ability to resist gastrointestinal nematode infection is considered to be dependent on the development of a protective acquired immune response, although the precise immune mechanisms involved in initiating this process remain to be fully elucidated. In this study, current knowledge on the innate and acquired host immune response to gastrointestinal nematode infection in sheep and the development of immunity is reviewed. PMID:26480845

  13. Cross-resistance to moxidectin and ivermectin on a meat sheep farm in France.

    Science.gov (United States)

    Paraud, C; Marcotty, T; Lespine, A; Sutra, J F; Pors, I; Devos, I

    2016-08-15

    Resistance to ivermectin and moxidectin was explored by a faecal egg count reduction test in two sheep flocks with suspected anthelmintic resistance. The FECRT confirmed one suspicion, with a mean percentage of reduction in egg excretion within the treated groups of 0% for ivermectin (CI 95%: -228 to 58) and 13% for moxidectin (CI 95%: -152 to 70). This was further explored by a controlled efficacy test. An experimental infection of 18 naïve lambs was set up using infective larvae isolated from this flock (5000 L3/lamb). Compared to the control group, abomasal worm burdens (Teladorsagia circumcincta) were reduced by 90% [CI 95%: 81.5-94.8] and 85% [CI 95%: 72.4-92.2] after ivermectin (p<0.05) and moxidectin (p<0.05) treatment respectively. Again, compared to the control group, there was a reduction for intestinal strongyles (Trichostrongylus colubriformis) of 100% and 99% [CI 95%: 97.5-99.7] for ivermectin and moxidectin respectively. No difference was found between the efficacy of moxidectin and ivermectin. Pharmacokinetic values indicated that the strongyles were submitted to anthelmintic concentrations usually lethal to them. This trial demonstrated the first multiple resistance of ovine strongyles in France. PMID:27514891

  14. Lack of Cyathostomin sp. reduction after anthelmintic treatment in horses in Brazil.

    Science.gov (United States)

    Canever, Ricardo J; Braga, Pollyana R C; Boeckh, Albert; Grycajuck, Marcelly; Bier, Daniele; Molento, Marcelo B

    2013-05-01

    The increase of anthelmintic resistance in the last years in the nematode population of veterinary importance has become a major concern. The objective of the present study was to evaluate the efficacy of the main anthelmintic drugs available in the market against small strongyles of horses in Brazil. A total of 498 horses from 11 horse farms, located in the states of Paraná, São Paulo, Rio de Janeiro and Minas Gerais, in Brazil, were treated with ivermectin, moxidectin, pyrantel and fenbendazole, orally at their recommended doses. The fecal egg count reduction test (FECRT) was used to determine the product's efficacy and fecal culture was used to determine the parasite genus. Reduction on anthelmintic efficacy was found for fenbendazole in all horse farms (11/11), pyrantel in five yards (5/11) and ivermectin had low efficacy in one of the yards studied (1/11). Multidrug resistance of up to 3 drugs classes was found in one of the tested farms (1/11). Cyathostomin were the most prevalent parasite. The results showed that resistance to fenbendazole is widespread; the efficacy of pyrantel is in a critical situation. Although the macrocyclic lactones compounds still showed high efficacy on most farms, suspected resistance to macrocyclic lactones is of great concern.

  15. In vitro anthelmintic activity of three medicinal plants against Haemonchus contortus

    Directory of Open Access Journals (Sweden)

    Eguale Tadesse

    2009-01-01

    Full Text Available The development of anthelmintic resistance and the high cost of conventional anthelmintic drugs led to the evaluation of medicinal plants as an alternative source of anthelmintics. In the current study, in-vitro experiments were conducted to determine the possible anthelmintic effects of crude aqueous and hydroalcoholic extracts of the leaves of Chenopodium ambrosioides, Lawsonia inermis and seeds of Jatropha curcas, on eggs and adult Haemonchus contortus. Both extracts of C. ambrosioides and J. curcas inhibited the hatching of eggs at a concentration less than or equal to 2mg/ml, while the effect of L. inermis was not dose-dependent and did not inhibit the hatching of eggs of H. contortus, significantly, at all tested concentrations. Based on their ED 50 , the two most potent extracts using egg hatch assay were the hydroalcoholic extract of C. ambrosioides (0.09mg/ml and the aqueous extract of J. curcas (0.1mg/ml in a decreasing order of potency. With regard to the effect of extracts on the survival of adult parasites, extracts from C. ambrosioides have shown a moderate effect, while J. curcas and L. inermis have shown no statistically significant effect on the survival of adult parasites at the concentrations tested, and the few mortality cases recorded were not dose-dependent ( P < 0.05. The overall findings of the present study have shown that C. ambrosioides and J. curcas contain possible anthelmintic compounds and further evaluation of these plants should be carried out.

  16. Origanum vulgare (Lamiaceae OVICIDAL POTENTIAL ON GASTROINTESTINAL NEMATODES OF CATTLE

    Directory of Open Access Journals (Sweden)

    Luciana Laitano Dias de Castro

    2013-12-01

    Full Text Available Due to anthelmintic resistance in nematodes, several research studies have been developed seeking control alternatives to these parasites. This study evaluated the in vitro action of Origanum vulgare on gastrointestinal nematode eggs of cattle. In order to evaluate the ability to inhibit egg hatch, different dried leaves extracts of this plant were tested, such as dye, hydroalcoholic and aqueous extracts at concentrations varying from 0.62 to 80 mg/mL. Each assay was accompanied by control containing levamisole hydrochloride (0.2 mg/mL, distilled water and 70 ºGL grain alcohol at the same concentration of the extracts. Test results showed that the different O. vulgare extracts inhibited egg hatch of cattle gastrointestinal nematodes at a percentage that varied from 8.8 to 100%; dye and hydroalcoholic extract were the most promising inhibitors. In view of this ovicidal property, O. vulgare may be an important source of viable antiparasitic compounds for nematodiosis control in ruminants.

  17. Larvicidal activity of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus.

    Science.gov (United States)

    DE Lara, Ana Paula DE Souza Stori; Lorenzon, Lucas Bigolin; Vianna, Ana Muñoz; Santos, Francisco Denis Souza; Pinto, Luciano Silva; Aires Berne, Maria Elisabeth; Leite, Fábio Pereira Leivas

    2016-10-01

    Effective control of gastrointestinal parasites is necessary in sheep production. The development of anthelmintics resistance is causing the available chemically based anthelmintics to become less effective. Biological control strategies present an alternative to this problem. In the current study, we tested the larvicidal effects of Bacillus thuringiensis var. israelensis Cry11Aa toxin against Haemonchus contortus larvae. Bacterial suspensions [2 × 108 colony-forming units (CFU) g-1 of the feces] of B. thuringiensis var. israelensis and recombinant Escherichia coli expressing Cry11Aa toxin were added to naturally H. contortus egg-contaminated feces. The larvae were quantified, and significant reductions of 62 and 81% (P < 0·001) were, respectively observed, compared with the control group. A 30 mL bacterial suspension (1 × 108 CFU mL-1) of B. thuringiensis var. israelensis and recombinant E. coli expressing Cry11Aa toxin were then orally administered to lambs naturally infected with H. contortus. Twelve hours after administration, feces were collected and submitted to coprocultures. Significant larvae reductions (P < 0·001) of 79 and 90% were observed respectively compared with the control group. The results suggest that the Cry11Aa toxin of B. thuringiensis var. israelensis is a promising new class of biological anthelmintics for treating sheep against H. contortus.

  18. FAMACHA©: A potential tool for targeted selective treatment of chronic fasciolosis in sheep.

    Science.gov (United States)

    Olah, Sophie; van Wyk, Jan A; Wall, Richard; Morgan, Eric R

    2015-09-15

    The liver fluke Fasciola hepatica causes considerable damage to the health, welfare and productivity of ruminants in temperate areas, and its control is challenged by anthelmintic resistance. Targeted selective treatment (TST) is an increasingly established strategy for preserving anthelmintic efficacy in grazing livestock, yet no practical indicators are available to target individuals for treatment against fluke infection. This paper evaluates the FAMACHA(©) system, a colour chart for the non-invasive detection of anaemia in small ruminants, for this purpose. FAMACHA(©) scores were collected from 288 sheep prior to slaughter during the winter period, when fluke infections were largely mature, and condemned livers were recovered and adult flukes extracted. Average FAMACHA(©) score was significantly higher (=paler conjunctivae) in animals whose livers were condemned (3.6, n=62) than in those whose livers were not condemned (2.1). The number of adult flukes recovered ranged from 2 to 485, and was positively correlated with FAMACHA(©) score (r(2)=0.54, ptreatment of individual sheep with FAMACHA(©) scores above 2 or 3 would have preserved between 27 and 100% of nematodes in refugia on the basis of FEC, depending on group and the threshold used for treatment. FAMACHA(©) holds promise as a tool for selective treatment of sheep against adult F. hepatica, in support of refugia-based control of fluke and nematode infections, and further field evaluation is warranted. PMID:26223154

  19. A model to assess the efficacy of vaccines for control of liver fluke infection.

    Science.gov (United States)

    Turner, Joanne; Howell, Alison; McCann, Cathy; Caminade, Cyril; Bowers, Roger G; Williams, Diana; Baylis, Matthew

    2016-01-01

    Fasciola hepatica, common liver fluke, infects cattle and sheep causing disease and production losses costing approximately $3 billion annually. Current control relies on drugs designed to kill the parasite. However, resistance is evident worldwide and widespread in some areas. Work towards a vaccine has identified several antigens of F. hepatica that show partial efficacy in terms of reducing worm burden and egg output. A critical question is what level of efficacy is required for such a vaccine to be useful? We have created the first mathematical model to assess the effectiveness of liver fluke vaccines under simulated field conditions. The model describes development of fluke within a group of animals and includes heterogeneity in host susceptibility, seasonal exposure to metacercariae and seasonal changes in temperature affecting metacercarial survival. Our analysis suggests that the potential vaccine candidates could reduce total fluke burden and egg output by up to 43% and 99%, respectively, on average under field conditions. It also suggests that for a vaccine to be effective, it must protect at least 90% of animals for the whole season. In conclusion, novel, partial, vaccines could contribute substantially towards fasciolosis control, reducing usage of anthelmintics and thus delaying the spread of anthelmintic resistance. PMID:27009747

  20. Substitution of benzimidazole-resistant nematodes for susceptible nematodes in grazing lambs.

    Science.gov (United States)

    Moussavou-Boussougou, M-N; Silvestre, A; Cortet, J; Sauve, C; Cabaret, J

    2007-04-01

    Multi-drug-resistant gastrointestinal nematode parasite populations are becoming more and more prevalent. Since anthelmintic treatments are of limited effectiveness, one solution could be to replace the anthelmintic-resistant population by a susceptible population, in order to re-establish the possibility of drug-based anthelmintic control. We investigated this substitution strategy in 4 paddocks of 0.7 ha, each of which was seeded with a benzimidazole-resistant Teladorsagia circumcincta population. The proportion of benzimidazole-resistant worms in these paddocks ranged from 20% to 89%. A 2-step replacement was performed: first, the paddocks were not grazed for 6 months (from December to July), and then the grass was cut to eliminate any residual infective larvae, before contaminating each of the paddocks with 10 seeder lambs experimentally infected with a benzimidazole-susceptible strain of T. circumcincta (from July to November). At the end of the experiment, all the populations on the 4 paddocks were phenotypically benzimidazole-susceptible, but genotyping indicated that 2 populations harboured 1% and 3% resistant worms respectively. This study demonstrates that nematode replacement is feasible in temperate areas, using semi-intensive stock management, even when the initial levels of benzimidazole-resistance are very high. Further research should next assess replacing the whole community to cope with the species diversity observed under field conditions. PMID:17096872

  1. Anthelmintic activity of Cymbopogon martinii, Cymbopogon schoenanthus and Mentha piperita essential oils evaluated in four different in vitro tests.

    Science.gov (United States)

    Katiki, L M; Chagas, A C S; Bizzo, H R; Ferreira, J F S; Amarante, A F T

    2011-12-29

    Anthelmintic resistance is a worldwide concern in small ruminant industry and new plant-derived compounds are being studied for their potential use against gastrointestinal nematodes. Mentha piperita, Cymbopogon martinii and Cymbopogon schoenanthus essential oils were evaluated against developmental stages of trichostrongylids from sheep naturally infected (95% Haemonchus contortus and 5% Trichostrogylus spp.) through the egg hatch assay (EHA), larval development assay (LDA), larval feeding inhibition assay (LFIA), and the larval exsheathment assay (LEA). The major constituent of the essential oils, quantified by gas chromatography for M. piperita oil was menthol (42.5%), while for C. martinii and C. schoenanthus the main component was geraniol (81.4% and 62.5%, respectively). In all in vitro tests C. schoenanthus essential oil had the best activity against ovine trichostrongylids followed by C. martini, while M. piperita presented the least activity. Cymbopogon schoenanthus essential oil had LC(50) value of 0.045 mg/ml in EHA, 0.063 mg/ml in LDA, 0.009 mg/ml in LFIA, and 24.66 mg/ml in LEA. The anthelmintic activity of essential oils followed the same pattern in all in vitro tests, suggesting C. schoenanthus essential oil could be an interesting candidate for nematode control, although in vivo studies are necessary to validate the anthelmintic properties of this oil.

  2. Domestication of ruminant livestock and the impact of nematode parasites:possible implications for the reindeer industry

    Directory of Open Access Journals (Sweden)

    Peter J. Waller

    2005-04-01

    Full Text Available In a balanced ecological system, both host and nematode parasite populations are firmly controlled by a complex array of interacting factors. However domestication of livestock has tipped the balance in favour of the parasites. This is due to increasing the proportion of susceptible animals in the herd or flock (lactating females and weaned young animals, increasing stocking rate, increasing productivity demands and decreasing the movement of the animals. In contrast with microbial infections, where multiplication takes place entirely within the host, metazoan parasites have both a parasitic phase and a free-living phase. Every worm present has been separately acquired by the ingestion of free-living stages on pasture. Immunity to nematodes develops slowly, it is labile, and its maintenance is dependent upon a good nutritional state of the animal. Consequently, worm parasites are ubiquitous wherever livestock are kept and they impose a constant and often a high infectious pressure on grazing animals. Nematode infections in grazing livestock are almost always a mixture of species. All have deleterious effects and collectively lead to chronic ill thrift. Economic evaluations repeatedly show that the major losses due to parasites are on animal production, rather than on mortality. This paper focuses on the problems of nematode parasites; problems associated with drug use (anthelmintic resistance, environmental impact and costs of nematode infections for the common ruminant livestock industries (cattle, sheep, goats, with possible analogies for the semi-domesticated reindeer industry.

  3. In vitro activity of neem (Azadirachta indica) and cassava (Manihot esculenta) on three pre-parasitic stages of susceptible and resistant strains of Teladorsagia (Ostertagia) circumcincta.

    Science.gov (United States)

    Al-Rofaai, A; Rahman, W A; Sulaiman, S F; Yahaya, Z S

    2012-08-13

    Anthelmintic resistance of gastrointestinal nematodes is considered as one of the main limiting factors causing significant economic losses to the small ruminant industry. The anthelmintic properties of some plants are among the suggested alternative solutions to control these parasitic worms. The present study investigated the anthelmintic activity of neem (Azadirachta indica) and cassava (Manihot esculenta) leaf extracts against the susceptible and resistant strains of one of the most important nematodes in small ruminants, Teladorsagia (Ostertagia) circumcincta. Three different in vitro tests: egg hatch test, larval development assay, and larval paralysis assay were used to determine the efficiency of neem and cassava extracts on three pre-parasitic stages of T. circumcincta. The LC(50) was determined for the most potent extract in each plant as well as the phytochemical tests, total tannin quantification and cytotoxicity on peripheral blood mononuclear cells of goats. The results revealed a high anthelmintic activity of neem methanol extract (NME) and cassava methanol extract (CME) on both strains of T. circumcincta without significant differences between the strains. The first stage larvae were more sensitive with the lowest LC(50) at 7.15 mg/ml and 10.72 mg/ml for NME and CME, respectively, compared with 44.20mg/ml and 56.68 mg/ml on eggs and 24.91 mg/ml and 71.96 mg/ml on infective stage larvae.

  4. Estimation of genetic parameters for resistance to gastro-intestinal nematodes in pure blood Arabian horses.

    Science.gov (United States)

    Kornaś, Sławomir; Sallé, Guillaume; Skalska, Marta; David, Ingrid; Ricard, Anne; Cabaret, Jacques

    2015-03-01

    Equine internal parasites, mostly cyathostomins, affect both horse welfare and performance. The appearance of anthelmintic-resistant parasites creates a pressing need for optimising drenching schemes. This optimization may be achieved by identifying genetic markers associated with host susceptibility to infection and then to drench carriers of these markers. The aim of our study was to characterise the genetics of horse resistance to strongyle infection by estimating heritability of this trait in an Arabian pure blood population. A population of 789 Arabian pure blood horses from the Michałów stud farm, Poland were measured for strongyle egg excretion twice a year, over 8 years. Low repeatability values were found for faecal egg counts. Our analyses showed that less than 10% of the observed variation for strongyle faecal egg counts in this population had a genetic origin. However, additional analyses highlighted an age-dependent increase in heritability which was 0.04 (±0.02) in young horses (up to 3 years of age) but 0.21 (±0.04) in older ones. These results suggest that a significant part of the inter-individual variation has a genetic origin. This paves the way to a genomic dissection of horse-nematode interactions which might provide predictive markers of susceptibility, allowing individualised drenching schemes. PMID:25592965

  5. In vivo assessment of closantel ovicidal activity in Fasciola hepatica eggs.

    Science.gov (United States)

    Solana, María Victoria; Mera y Sierra, Roberto; Scarcella, Silvana; Neira, Gisela; Solana, Hugo Daniel

    2016-01-01

    Anthelmintic resistance in livestock parasites is currently a worldwide problem. Fasciola hepatica is a cosmopolitan parasite which causes considerable loss in sheep and cattle production systems all over the world. Chemotherapy is currently the main tool available for its control. The intensive use of triclabendazole, the drug of choice for more than 20 years, has resulted in the development of resistant strains. The therapeutic options are adulticides such as closantel (salicylanilide anthelmintic that binds extensively to plasma albumin) to treat chronic fascioliasis in sheep, and cattle. In the present work, an Egg Hatch Assay (EHA) and morphometric studies were used to evaluate in vivo the ovicidal activity and morphology F. hepatica eggs, recovered from closantel treated sheep collected at different time intervals post treatment. Statistically significant differences (p < 0.0001) were observed in egg morphometry between the control and the treated groups in all the parameters studied. Eggs recovered from treated animals tend to be narrower and longer. Significant differences were found in the embryonation and hatching of eggs between 36 h post treatment (32, 5%) vs. approximately 85% in control, 12 h and 24 h post treatment. Our results confirm that closantel affects in vivo the normal development of the eggs. As one of the first effects, this drug affects the performance of the trematode's reproductive physiology. Even though closantel treated animals may still eliminate eggs in the first days post treatment, these are not viable.

  6. Microbiota characterization of a Belgian protected designation of origin cheese, Herve cheese, using metagenomic analysis.

    Science.gov (United States)

    Delcenserie, V; Taminiau, B; Delhalle, L; Nezer, C; Doyen, P; Crevecoeur, S; Roussey, D; Korsak, N; Daube, G

    2014-10-01

    Herve cheese is a Belgian soft cheese with a washed rind, and is made from raw or pasteurized milk. The specific microbiota of this cheese has never previously been fully explored and the use of raw or pasteurized milk in addition to starters is assumed to affect the microbiota of the rind and the heart. The aim of the study was to analyze the bacterial microbiota of Herve cheese using classical microbiology and a metagenomic approach based on 16S ribosomal DNA pyrosequencing. Using classical microbiology, the total counts of bacteria were comparable for the 11 samples of tested raw and pasteurized milk cheeses, reaching almost 8 log cfu/g. Using the metagenomic approach, 207 different phylotypes were identified. The rind of both the raw and pasteurized milk cheeses was found to be highly diversified. However, 96.3 and 97.9% of the total microbiota of the raw milk and pasteurized cheese rind, respectively, were composed of species present in both types of cheese, such as Corynebacterium casei, Psychrobacter spp., Lactococcus lactis ssp. cremoris, Staphylococcus equorum, Vagococcus salmoninarum, and other species present at levels below 5%. Brevibacterium linens were present at low levels (0.5 and 1.6%, respectively) on the rind of both the raw and the pasteurized milk cheeses, even though this bacterium had been inoculated during the manufacturing process. Interestingly, Psychroflexus casei, also described as giving a red smear to Raclette-type cheese, was identified in small proportions in the composition of the rind of both the raw and pasteurized milk cheeses (0.17 and 0.5%, respectively). In the heart of the cheeses, the common species of bacteria reached more than 99%. The main species identified were Lactococcus lactis ssp. cremoris, Psychrobacter spp., and Staphylococcus equorum ssp. equorum. Interestingly, 93 phylotypes were present only in the raw milk cheeses and 29 only in the pasteurized milk cheeses, showing the high diversity of the microbiota

  7. Microbiological and physicochemical characterization of dry-cured Halal goat meat. Effect of salting time and addition of olive oil and paprika covering.

    Science.gov (United States)

    Cherroud, Sanâa; Cachaldora, Aida; Fonseca, Sonia; Laglaoui, Amin; Carballo, Javier; Franco, Inmaculada

    2014-10-01

    The objective of this work was to define a simple technological process for dry-cured Halal goat meat elaboration. The aims of this study were to analyze physicochemical parameters and to enumerate the microbial population at the end of the different manufacturing processes (two salting times and the addition of olive oil and paprika covering) on 36 units of meat product. A total of 532 strains were isolated from several selective culture media and then identified using classical and molecular methods. In general, salt effect and the addition of olive oil and paprika were significant for all the studied microbial groups as well as on NaCl content and water activity. Molecular analysis proves that staphylococci, especially Staphylococcus xylosus and Staphylococcus equorum, were the most common naturally occurring microbiota. The best manufacturing process would be obtained with a longer salting time and the addition of the olive oil and paprika covering. PMID:24950081

  8. HEALTH AND HYGIENIC CONDITIONS OF EWE'S MILK PROCESSING FROM THE ASPECT OF FOOD SAFETY

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    Jana Pukáčová

    2010-07-01

    Full Text Available Totally, 47 strains of S. aureus and 578 coagulase negative staphylococci were detected in samples from raw ewe milk. The 35 out 47 isolates of S. aureus from ewe milk were positive for the presence of staphylococcal enterotoxin genes: sea(4 %, sec (48 % a sed (48 %. Staphylococcus epidermis (33.04%, Staphylococcus caprae (21.28% were more prevalent. Staphylococcus chromogenes (7.44 %, Staphylococcus hominis (7.09%, Staphylococcus xylosus (6,92 %, a Staphylococcus warneri (6.40 % were isolated also in ewes milk. Staphylococcus haemolyticus (3.11 %, Staphylococcus capitis (2.94 %, Staphylococcus simulans (2.08 % and Staphylococcus saprophyticus (1.73 % were isolated very rarely from the taken individual milk ewe samples. Sporadically, only in few cases, the others coagulase negative staphylococci were isolated (Staphylococcus cohnii cohnii, Staphylococcus sciuri, Staphylococcus closii, Staphylococcus lugdunensis, Staphylococcus auricularis and Staphylococcus equorum.   doi:10.5219/24

  9. Further evidence for the existence of environmental and host-associated species of coagulase-negative staphylococci in dairy cattle.

    Science.gov (United States)

    De Visscher, Anneleen; Supré, Karlien; Haesebrouck, Freddy; Zadoks, Ruth N; Piessens, Veerle; Van Coillie, Els; Piepers, Sofie; De Vliegher, Sarne

    2014-08-27

    Coagulase-negative staphylococci (CNS) are abundantly present in the dairy farm environment and on bovine skin and mucosae. They are also the most prevalent bacteria causing bovine intramammary infections (IMI). Reservoirs and transmission routes of CNS are not yet fully unraveled. The objectives of this study were to explore the distribution of CNS in parlor-related extramammary niches and to compare it to the distributions of CNS causing IMI in those herds. Niches that were targeted in this study were cows' teat apices, milking machine unit liners, and milker's skin or gloves. Each of the three herds had its own CNS microbiota in those niches. The most prevalent species in the parlor-related extramammary niches were Staphylococcus cohnii, S. fleurettii, and S. equorum in the first, second, and third herd, respectively, whereas S. haemolyticus and S. sciuri were found in all herds. S. cohnii and S. fleurettii, as well as S. haemolyticus, which was present in each herd, were also frequently found in milk samples. By contrast, S. chromogenes, S. simulans, and S. xylosus favored the mammary gland, whereas S. equorum was more common in the parlor-associated niches. Within each herd, species distribution was similar between teat apices and milking machine unit liners. In conclusion, some of the extramammary niches related to the milking process might act as infection sources for IMI-causing CNS. This study provides further evidence that the group of CNS species is comprised of environmental, opportunistic and host-adapted species which differ in ecology. PMID:25008316

  10. Bacterial ecology of PDO Coppa and Pancetta Piacentina at the end of ripening and after MAP storage of sliced product.

    Science.gov (United States)

    Busconi, Matteo; Zacconi, Carla; Scolari, Gianluigi

    2014-02-17

    The objective of this study was to evaluate the microbiota of two typical Italian PDO delicatessens Coppa and Pancetta Piacentina, produced in Piacenza area (Italy). Classical and molecular approaches were employed, in order to acquire knowledge on their bacterial ecology and its evolution after slicing and MAP storing; thus, the biodiversity of characteristic bacterial community, already present or introduced during such procedures, was studied in both full ripened and sliced samples from two producers (A and B) of the PDO district, packaged under MAP and stored at 2 and 8 °C for 30 days. The microbiota of the two kinds of Italian delicatessen demonstrated peculiar differences, particularly regarding the staphylococci and lactic acid bacteria (LAB) ratio. Moreover, some species within these two groups appeared to be linked to the kind of product: Leuconostoc, Lactobacillus versmoldensis and Staphylococcus saprophyticus were found only in Pancetta while Lactobacillus pentosus, Staphylococcus equorum, Staphylococcus xylosus, Staphylococcus sciuri and Macrococcus caseolyticus occurred only in Coppa. Also, both delicatessens from producer A were richer in LAB compared to those of producer B and the opposite applied for staphylococci. Interestingly, Tetragenococcus halophilus was detectable in all the samples and its presence in the sausage environment has been reported only for Capocollo. Storage did not substantially modify the microbiota composition, the only changes being the relative abundance of same sequences; S. xylosus was prevalent before slicing process and S. equorum at the end of MAP storage at both 2 °C and 8 °C. Concerning microbial contamination during the slicing process, our results suggest that the adopted procedures assure high hygienic quality standard of these typical products, with exception of a contamination by Psychrobacter psychrophilus in Coppa B. The possible origin of species rarely or never reported in the sausage environment and

  11. Genetic classification and distinguishing of Staphylococcus species based on different partial gap, 16S rRNA, hsp60, rpoB, sodA, and tuf gene sequences.

    Science.gov (United States)

    Ghebremedhin, B; Layer, F; König, W; König, B

    2008-03-01

    The analysis of 16S rRNA gene sequences has been the technique generally used to study the evolution and taxonomy of staphylococci. However, the results of this method do not correspond to the results of polyphasic taxonomy, and the related species cannot always be distinguished from each other. Thus, new phylogenetic markers for Staphylococcus spp. are needed. We partially sequenced the gap gene (approximately 931 bp), which encodes the glyceraldehyde-3-phosphate dehydrogenase, for 27 Staphylococcus species. The partial sequences had 24.3 to 96% interspecies homology and were useful in the identification of staphylococcal species (F. Layer, B. Ghebremedhin, W. König, and B. König, J. Microbiol. Methods 70:542-549, 2007). The DNA sequence similarities of the partial staphylococcal gap sequences were found to be lower than those of 16S rRNA (approximately 97%), rpoB (approximately 86%), hsp60 (approximately 82%), and sodA (approximately 78%). Phylogenetically derived trees revealed four statistically supported groups: S. hyicus/S. intermedius, S. sciuri, S. haemolyticus/S. simulans, and S. aureus/epidermidis. The branching of S. auricularis, S. cohnii subsp. cohnii, and the heterogeneous S. saprophyticus group, comprising S. saprophyticus subsp. saprophyticus and S. equorum subsp. equorum, was not reliable. Thus, the phylogenetic analysis based on the gap gene sequences revealed similarities between the dendrograms based on other gene sequences (e.g., the S. hyicus/S. intermedius and S. sciuri groups) as well as differences, e.g., the grouping of S. arlettae and S. kloosii in the gap-based tree. From our results, we propose the partial sequencing of the gap gene as an alternative molecular tool for the taxonomical analysis of Staphylococcus species and for decreasing the possibility of misidentification.

  12. MICROBIOLOGICAL EVOLUTION OF DACIA SAUSAGE, A DRY CURED ROMANIAN SAUSAGE

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    Ana Maria Simion Ciuciu

    2011-09-01

    Full Text Available Selected starter cultures were used to produce the traditional Romanian dry cured sausage, Dacia. A control sausage was produced without starter culture (sausage A, one with L. sakei CECT 5964 and S. equorum SA25 (sausage B and one with L. sakei CECT 5964, S. equorum SA25 and L. acidophilus CECT 903 (sausage C. Samples from each batch of sausages were taken at 0 (mix before stuffing, and after 2, 4, 7, 14, 21 and 28 days of ripening. Counts of total aerobic mesophilic flora, lactic acid bacteria, salt tolerant flora, and Enterobacteriaceae and some physical-chemical parameters (moisture, NaCl, pH and aw values were determined. High microbial counts (log CFU were observed with values at the end of ripening period: for lactic acid bacteria 9.77 (A, 11.47 (B and 11.19 (C; for total aerobic mesophilic flora 9.89 (A, 11.38 (B and 11.30 (C; for salt tolerant flora 4.45 (A, 5.31 (B and 5.27 (C. The starter cultures had a significant inhibitory effect on Enterobacteriaceae counts (log CFU, values at the end of ripening period being 1.32 (A, 0.33 (B and not detected (C. A significant decrease in the pH values is observed until the seventh day of ripening, showing a slight, but progressive increase after the 14th day of ripening. Results show that the production and ripening process in a pilot scale chamber under controlled conditions contributes in obtaining safe and homogeneous products.

  13. L-methionine degradation potentialities of cheese-ripening microorganisms.

    Science.gov (United States)

    Bonnarme, P; Lapadatescu, C; Yvon, M; Spinnler, H E

    2001-11-01

    Volatile sulphur compounds are major flavouring compounds in many traditional fermented foods including cheeses. These compounds are products of the catabolism of L-methionine by cheese-ripening microorganisms. The diversity of L-methionine degradation by such microorganisms, however, remains to be characterized. The objective of this work was to compare the capacities to produce volatile sulphur compounds by five yeasts, Geotrichum candidum, Yarrowia lipolytica, Kluyveromyces lactis, Debaryomyces hansenii, Saccharomyces cerevisiae and five bacteria, Brevibacterium linens, Corynebacterium glutamicum, Arthrobacter sp., Micrococcus lutens and Staphylococcus equorum of technological interest for cheese-ripening. The ability of whole cells of these microorganisms to generate volatile sulphur compounds from L-methionine was compared. The microorganisms produced a wide spectrum of sulphur compounds including methanethiol, dimethylsulfide, dimethyldisulfide, dimethyltrisulfide and also S-methylthioesters, which varied in amount and type according to strain. Most of the yeasts produced methanethiol, dimethylsulfide, dimethyldisulfide and dimethyltrisulfide but did not produce S-methylthioesters, apart from G. candidum that produced S-methyl thioacetate. Bacteria, especially Arth. sp. and Brevi. linens, produced the highest amounts and the greatest variety of volatile sulphur compounds includling methanethiol, sulfides and S-methylthioesters, e.g. S-methyl thioacetate, S-methyl thiobutyrate, S-methyl thiopropionate and S-methyl thioisovalerate. Cell-free extracts of all the yeasts and bacteria were examined for the activity of enzymes possibly involved in L-methionine catabolism, i.e. L-methionine demethiolase, L-methionine aminotransferase and L-methionine deaminase. They all possessed L-methionine demethiolase activity, while some (K. lactis, Deb. hansenii, Arth. sp., Staph. equorum) were deficient in L-methionine aminotransferase, and none produced L-methionine deaminase

  14. Partial characterization of superoxide dismutase activity in the Barber pole worm-Haemonchus contortus infecting Capra hircus and abomasal tissue extracts

    Institute of Scientific and Technical Information of China (English)

    Sadia Rashid; Malik Irshadullah

    2014-01-01

    Objective: To determine the activity of superoxide dismutase (SOD) in the male and female haematophagous caprine worms, Haemonchus contortus infecting Capra hircus, and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD. Methods: The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method. Results: The adult females were found to have higher enzyme activity than the male worms. Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites. The SOD activity was negatively correlated to the worm burden. Statistically significant decrease in SOD activity (P Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery. The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack. SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world. The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential. One characteristic SOD band was found in the females which was not present in any other preparations and thus could be exploited for further studies on diagnostic/control measures.

  15. Familiarity with and uptake of alternative methods to control sheep gastro-intestinal parasites on farms in England.

    Science.gov (United States)

    Moore, Hope; Pandolfi, Fanny; Kyriazakis, Ilias

    2016-05-15

    A questionnaire was distributed electronically amongst sheep farmers in England; it aimed to provide a quantification of current anthelmintic practices, farmer awareness of the issue of anthelmintic resistance (AR) and the uptake, awareness and opinions surrounding conventional and alternative methods of nematode control. The majority of farmers relied on several anthelmintics and used faecal egg counts to identify worm problems. Although farmers were aware of the issue of AR amongst helminth parasites in the UK, there was a disconnection between such awareness and on farm problems and practice of nematode control. Grazing management was used by 52% of responders, while breeding for resistance and bioactive forages by 22 and 18% respectively. Farms with more than 500 ewes, and farmers who felt nematodes were a problem, had a higher probability of using selective breeding. Farmers who considered their wormer effective, had a qualification in agriculture and whose staff did not include any family members, were more likely to use bioactive forages; the opposite was the case if farmers dosed their lambs frequently. Amongst the alternatives, highest preference was for selective breeding and vaccination, if the latter was to become commercially available, with more respondents having a preference for breeding than actually using it. Several barriers to the uptake of an alternative were identified, the most influential factor being the cost to set it up and the length of time for which it would remain effective. The disconnection between awareness of AR and practice of nematode control on farm reinforces the need for emphasising the links between the causes of AR and the consequences of strategies to address its challenge. PMID:27084464

  16. Evaluation of resistance in a selected field strain of Haemonchus contortus to ivermectin and moxidectin using the Larval Migration on Agar Test

    Directory of Open Access Journals (Sweden)

    Fernanda S. Fortes

    2013-02-01

    Full Text Available Haemonchus contortus is one of the most common and economically significant causes of disease in small ruminants worldwide, and the control programs of parasitic nematodes - including H. contortus - rely mostly on the use of anthelmintic drugs. The consequence of the use of this, as the sole sanitary strategy to avoid parasite infections, was the reduction of the efficacy of all chemotherapeutic products with a heavy selection for resistance. The widespread of anthelmintic resistance and the difficulty of its early diagnosis has been a major concern for the sustainable parasite management on farms. The objective of this research was to determine and compare the ivermectin (IVM and moxidectin (MOX effect in a selected field strain of H. contortus with a known resistance status, using the in vitro larval migration on agar test (LMAT. Third stage larvae of the selected isolate were obtained from faecal cultures of experimentally infected sheep and incubated in eleven increasing diluted concentrations of IVM and MOX (6, 12, 24, 48, 96, 192, 384, 768, 1536, 3072 and 6144µg/mL. The dose-response sigmoidal curves were obtained using the R² value of >0.90 and the lethal concentration (LC50 dose for the tested anthelmintic drugs using a four-parameter logistic model. The LC50 value for MOX was significantly lower than IVM (1.253µg/mL and 91.06µg/mL, identifying the H. contortus isolate as considerably less susceptible to IVM compared to MOX. Furthermore, the LMAT showed a high consistency (p<0.0001 and provided to be a useful diagnostic tool for monitoring the resistance status of IVM and MOX in H. contortus field isolate, as well as it may be used for official routine drug monitoring programs under the Ministry of Agriculture (MAPA guidance.

  17. Phenotypic and genotypic characterisation of Haemonchus spp. and other gastrointestinal nematodes resistant to benzimidazole in infected calves from the tropical regions of Campeche State, Mexico.

    Science.gov (United States)

    Encalada-Mena, Lisandro; Tuyub-Solis, Henry; Ramirez-Vargas, Gabriel; Mendoza-de-Gives, Pedro; Aguilar-Marcelino, Liliana; López-Arellano, Ma Eugenia

    2014-09-15

    The aim of this study was to identify the presence of anthelmintic resistance to benzimidazole (BZ) in gastrointestinal nematodes (GIN) from naturally infected calves in the tropical regions of Campeche State of Mexico. The faecal egg count reduction test (FECRT) was conducted at 10 livestock farms localised in the Carmen, Candelaria, Champotón, Escárcega and Palizada municipalities of Campeche. The assessed anthelmintic was albendazole. The trial period was between August and November 2012. Infected calves were allocated into two groups, control and treated, on each farm. The number of eggs excreted per g of faeces was estimated by the McMaster technique at 0 and 14 days pre- and post- treatment, respectively. Recovered infective larvae (L3) (pre- and post-treatment) were identified using taxonomic keys and a genomic DNA (gDNA) template from a pool of L3 species prior to BZ treatment. Additionally, BZ-resistance polymorphisms in Haemonchus were determined by Allele Specific PCR (AS-PCR) at codon 200 and by end-point PCR at codons 200, 198 and 167 from isotype 1 of the β-tubulin gene. Morphological identification revealed Haemonchus, Cooperia, Trichostrongylus, Ostertagia and Oesophagostumum L3 species before BZ treatment, and Haemonchus and Cooperia L3 species after treatment. Additionally, of the GIN populations, three exhibited BZ resistance, and seven were BZ-susceptible by FECRT. Molecular analysis identified mutations in Haemonchus populations on nine farms at codon 200 (TTC to TAC) by AS-PCR, while no changes were observed at 167 (TTC to TAC) or 198 (GAA to GCA) codons in any population. In conclusion, resistance to BZ was determined in Haemonchus and Cooperia nematodes in infected cattle in five tropical regions of Campeche State.

  18. Mixed methods evaluation of targeted selective anthelmintic treatment by resource-poor smallholder goat farmers in Botswana.

    Science.gov (United States)

    Walker, Josephine G; Ofithile, Mphoeng; Tavolaro, F Marina; van Wyk, Jan A; Evans, Kate; Morgan, Eric R

    2015-11-30

    Due to the threat of anthelmintic resistance, livestock farmers worldwide are encouraged to selectively apply treatments against gastrointestinal nematodes (GINs). Targeted selective treatment (TST) of individual animals would be especially useful for smallholder farmers in low-income economies, where cost-effective and sustainable intervention strategies will improve livestock productivity and food security. Supporting research has focused mainly on refining technical indicators for treatment, and much less on factors influencing uptake and effectiveness. We used a mixed method approach, whereby qualitative and quantitative approaches are combined, to develop, implement and validate a TST system for GINs in small ruminants, most commonly goats, among smallholder farmers in the Makgadikgadi Pans region of Botswana, and to seek better understanding of system performance within a cultural context. After the first six months of the study, 42 out of 47 enrolled farmers were followed up; 52% had monitored their animals using the taught inspection criteria and 26% applied TST during this phase. Uptake level showed little correlation with farmer characteristics, such as literacy and size of farm. Herd health significantly improved in those herds where anthelmintic treatment was applied: anaemia, as assessed using the five-point FAMACHA(©) scale, was 0.44-0.69 points better (95% confidence interval) and body condition score was 0.18-0.36 points better (95% C.I., five-point scale) in treated compared with untreated herds. Only targeting individuals in greatest need led to similar health improvements compared to treating the entire herd, leading to dose savings ranging from 36% to 97%. This study demonstrates that TST against nematodes can be implemented effectively by resource-poor farmers using a community-led approach. The use of mixed methods provides a promising system to integrate technical and social aspects of TST programmes for maximum uptake and effect. PMID

  19. Characterization of Haemonchus contortus P-glycoprotein-16 and its interaction with the macrocyclic lactone anthelmintics.

    Science.gov (United States)

    Godoy, P; Che, H; Beech, R N; Prichard, R K

    2015-11-01

    Anthelmintic resistance in veterinary nematodes, including Haemonchus contortus, has become a limitation to maintaining high standards of animal health. Resistance in this parasite, to all drug families including the macrocyclic lactones (MLs) is a serious issue worldwide. Mechanisms of resistance to the MLs appear to be complex and to include the elimination of these compounds by ABC transporter-like proteins present in nematodes. In order to investigate the potential involvement of ABC transporters in ML resistance in H. contortus, we have characterized the functionality of the ABC transporter H. contortus P-glycoprotein-16 (Hco-PGP-16) expressed in mammalian cells. This has included a study of its interaction with different MLs, including the avermectins, abamectin (ABA) and ivermectin (IVM), and the milbemycin, moxidectin (MOX). Hco-PGP-16 transport activity was studied using the fluorophore Rhodamine 123 (Rho 123). Transfected cells expressing Hco-PGP-16 accumulated less than 50% of Rho 123 than control cells, suggesting an active transport of this tracer dye by Hco-PGP-16. The influence of the MLs on the Rho123 transport by Hco-PGP-16 was then investigated. A marked inhibition of Rho123 transport by ABA and IVM was observed. In contrast, MOX showed less effect on inhibition of Rho123 transport by Hco-PGP-16, and the inhibition was not saturable. The difference in the interaction of the avermectins and MOX with Hco-PGP-16 may help explain the slower rate of development of resistance to MOX compared with the avermectins in H. contortus.

  20. Prevalence of strongyles and efficacy of fenbendazole and ivermectin in working horses in El Sauce, Nicaragua.

    Science.gov (United States)

    Kyvsgaard, Niels C; Lindbom, Jenny; Andreasen, Line Lundberg; Luna-Olivares, Luz Adilia; Nielsen, Martin Krarup; Monrad, Jesper

    2011-09-27

    Horses, mules and donkeys are indispensable farming and working animals in many developing countries, and their health status is important to the farmers. Strongyle parasites are ubiquitous in grazing horses world-wide and are known to constitute a threat to equine health. This study determined the prevalence of strongyle infection, the efficacy of ivermectin and fenbendazole treatment, and strongyle re-infection rates of working horses during the dry months in Nicaragua. One hundred and five horses used by farmers for transport of people and goods were randomly allocated into three treatment groups, i.e., the IVM group treated with ivermectin, the FBZ group treated with fenbendazole and the control group treated with placebo. Determined by pre-treatment faecal egg counts (FECs), horses showed a high prevalence (94%) of strongyle parasites with high intensities of infection (mean FEC of 1117 eggs per gram (EPG) with an SD of 860 EPG, n=102). Body condition scores of all horses ranged from 1.5 to 3.5 with a mean of 2.4 (scales 1-5). Fourteen days after treatment faecal egg count reductions (FECRs) were 100% and 94% in the IVM and the FBZ groups, respectively. The egg reappearance period (ERP) defined as the time until the mean FEC reached 20% of the pre-treatment level, was estimated as 42 days for the FBZ group and 60 days for the IVM group. Individual faecal cultures were set up and the larval differentiation revealed a 36% prevalence of Strongylus vulgaris before treatment (n=45). In the FBZ group, 25% of the horses were S. vulgaris-positive 70 days post treatment compared to 11% in the IVM group. Our results indicate that strongyle infection intensities in Nicaragua are high and that S. vulgaris is endemic in the area. Furthermore, efficacies and ERPs of IVM and FBZ were within the expected range with no signs of anthelmintic resistance.

  1. Proteomic analysis of Mecistocirrus digitatus and Haemonchus contortus intestinal protein extracts and subsequent efficacy testing in a vaccine trial.

    Directory of Open Access Journals (Sweden)

    Alison J Dicker

    2014-06-01

    distribution are limited. The application of such a vaccine in these regions would reduce the need for anthelmintic treatment and the resultant selection for anthelmintic resistant parasites.

  2. Influence of immunoprotection on genetic variability of cysteine proteinases from Haemonchus contortus adult worms.

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    Martín, S; Molina, J M; Hernández, Y I; Ferrer, O; Muñoz, Ma C; López, A; Ortega, L; Ruiz, A

    2015-11-01

    The limitations associated with the use of anthelmintic drugs in the control of gastrotintestinal nematodosis, such as the emergence of anthelmintic resistance, have stimulated the study of the immunological control of many parasites. In the case of Haemonchus contortus, several vaccination trials using native and recombinant antigens have been conducted. A group of antigens with demonstrated immunoprotective value are cathepsin B - like proteolytic enzymes of the cysteine proteinase type. These enzymes, which have been observed in both excretory-secretory products and somatic extracts of H. contortus, may vary among different geographic isolates and on strains isolated from different hosts, or even from the same host, as has been demonstrated in some comparative studies of genetic variability. In the present study, we evaluated the genetic variability of the worms that fully developed their endogenous cycle in immunised sheep and goat in order to identify the alleles of most immunoprotective value. To address these objectives, groups of sheep and goats were immunised with PBS soluble fractions enriched for cysteine proteinases from adult worms of H. contortus from either a strain of H. contortus isolated from goats of Gran Canaria Island (SP) or a strain isolated from sheep of North America (NA). The results confirmed the immunoprophylactic value of this type of enzyme against haemonchosis in both sheep and goats in association with increased levels of specific IgG. The genetic analysis demonstrated that the immunisation had a genetic selection on proteinase-encoding genes. In all the immunised animals, allelic frequencies were statistically different from those observed in non-immunised control animals in the four analysed genes. The reduction in the allelic frequencies suggests that parasites expressing these proteases are selectively targeted by the vaccine, and hence they should be considered in any subunit vaccine approach to control haemonchosis in small

  3. An analysis of genetic diversity and inbreeding in Wuchereria bancrofti: implications for the spread and detection of drug resistance.

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    Thomas S Churcher

    Full Text Available Estimates of genetic diversity in helminth infections of humans often have to rely on genotyping (immature parasite transmission stages instead of adult worms. Here we analyse the results of one such study investigating a single polymorphic locus (a change at position 200 of the beta-tubulin gene in microfilariae of the lymphatic filarial parasite Wuchereria bancrofti. The presence of this genetic change has been implicated in benzimidazole resistance in parasitic nematodes of farmed ruminants. Microfilariae were obtained from patients of three West African villages, two of which were sampled prior to the introduction of mass drug administration. An individual-based stochastic model was developed showing that a wide range of allele frequencies in the adult worm populations could have generated the observed microfilarial genetic diversity. This suggests that appropriate theoretical null models are required in order to interpret studies that genotype transmission stages. Wright's hierarchical F-statistic was used to investigate the population structure in W. bancrofti microfilariae and showed significant deficiency of heterozygotes compared to the Hardy-Weinberg equilibrium; this may be partially caused by a high degree of parasite genetic differentiation between hosts. Studies seeking to quantify accurately the genetic diversity of helminth populations by analysing transmission stages should increase their sample size to account for the variability in allele frequency between different parasite life-stages. Helminth genetic differentiation between hosts and non-random mating will also increase the number of hosts (and the number of samples per host that need to be genotyped, and could enhance the rate of spread of anthelmintic resistance.

  4. Global Change and Helminth Infections in Grazing Ruminants in Europe: Impacts, Trends and Sustainable Solutions

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    Hubertus Hertzberg

    2013-08-01

    Full Text Available Infections with parasitic helminths (nematodes and trematodes represent a significant economic and welfare burden to the global ruminant livestock industry. The increasing prevalence of anthelmintic resistance means that current control programmes are costly and unsustainable in the long term. Recent changes in the epidemiology, seasonality and geographic distribution of helminth infections have been attributed to climate change. However, other changes in environment (e.g., land use and in livestock farming, such as intensification and altered management practices, will also have an impact on helminth infections. Sustainable control of helminth infections in a changing world requires detailed knowledge of these interactions. In particular, there is a need to devise new, sustainable strategies for the effective control of ruminant helminthoses in the face of global change. In this paper, we consider the impact of helminth infections in grazing ruminants, taking a European perspective, and identify scientific and applied priorities to mitigate these impacts. These include the development and deployment of efficient, high-throughput diagnostic tests to support targeted intervention, modelling of geographic and seasonal trends in infection, more thorough economic data and analysis of the impact of helminth infections and greater translation and involvement of end-users in devising and disseminating best practices. Complex changes in helminth epidemiology will require innovative solutions. By developing and using new technologies and models, the use of anthelmintics can be optimised to limit the development and spread of drug resistance and to reduce the overall economic impact of helminth infections. This will be essential to the continued productivity and profitability of livestock farming in Europe and its contribution to regional and global food security.

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

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    Bob Storey

    2014-12-01

    Full Text Available 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

  6. Genetic variation in codons 167, 198 and 200 of the beta-tubulin gene in whipworms (Trichuris spp.) from a range of domestic animals and wildlife.

    Science.gov (United States)

    Hansen, Tina V A; Nejsum, Peter; Olsen, Annette; Thamsborg, Stig Milan

    2013-03-31

    A recurrent problem in the control of whipworm (Trichuris spp.) infections in many animal species and man is the relatively low efficacy of treatment with a single application of benzimidazoles (BZs). The presence of single nucleotide polymorphisms (SNPs) in codons 167, 198 and 200 in the beta-tubulin gene has been associated with BZ anthelmintic resistance in intestinal nematodes of veterinary importance. We hypothesized that the low susceptibility to BZ could be related to a natural tolerance or induced resistance caused by BZ-resistant associated SNPs. The aim of the present study was therefore to investigate the presence of these SNPs in the beta-tubulin gene of Trichuris spp. obtained from a range of animals. DNA was extracted from a total of 121 Trichuris spp. adult whipworm specimens obtained from 6 different host species. The number of worms from each host was pig: 31, deer: 21, sheep: 18, mouse: 17, dog: 19 and Arabian camels: 14. A pooled sample of Trichuris eggs from 3 moose was also used. In order to amplify the beta-tubulin fragments which covered codons 167, 198 and 200 of the gene, degenerate primers were designed. The sequences obtained were used to design species specific primers and used to amplify a ~476 bp fragment of the beta-tubulin gene. The PCR products were sequenced, analysed and evaluated. We did not identify SNPs in codons 167, 198 or 200 that led to amino acid substitutions in any of the studied Trichuris spp., but genetic variation expected to be related to species differences was observed. The cluster analysis showed close evolutionary relationship between Trichuris spp. from ruminants and between mouse and dog whereas the pig-derived worms, T. suis, clustered with T. trichiura obtained from Genbank.

  7. Trickle or clumped infection process? A stochastic model for the infection process of the parasitic roundworm of humans, Ascaris lumbricoides.

    Science.gov (United States)

    Walker, Martin; Hall, Andrew; Basáñez, María-Gloria

    2010-10-01

    The importance of the mode of acquisition of infectious stages of directly-transmitted parasitic helminths has been acknowledged in population dynamics models; hosts may acquire eggs/larvae singly in a "trickle" type manner or in "clumps". Such models have shown that the mode of acquisition influences the distribution and dynamics of parasite loads, the stability of host-parasite systems and the rate of emergence of anthelmintic resistance, yet very few field studies have allowed these questions to be explored with empirical data. We have analysed individual worm weight data for the parasitic roundworm of humans, Ascaris lumbricoides, collected from a three-round chemo-expulsion study in Dhaka, Bangladesh, with the aim of discerning whether a trickle or a clumped infection process predominates. We found that hosts tend to harbour female worms of a similar weight, indicative of a clumped infection process, but acknowledged that unmeasured host heterogeneities (random effects) could not be completely excluded as a cause. Here, we complement our previous statistical analyses using a stochastic infection model to simulate sizes of individual A. lumbricoides infecting a population of humans. We use the intraclass correlation coefficient (ICC) as a quantitative measure of similarity among simulated worm sizes and explore the behaviour of this statistic under assumptions corresponding to trickle or clumped infections and unmeasured host heterogeneities. We confirm that both mechanisms are capable of generating aggregates of similar-sized worms, but that the particular pattern of ICCs described pre- and post-anthelmintic treatment in the data is more consistent with aggregation generated by clumped infections than by host heterogeneities alone. This provides support to the notion that worms may be acquired in clumps. We discuss our results in terms of the population biology of A. lumbricoides and highlight the significance of our modelling approach for the study of the

  8. Trickle or clumped infection process? An analysis of aggregation in the weights of the parasitic roundworm of humans, Ascaris lumbricoides.

    Science.gov (United States)

    Walker, Martin; Hall, Andrew; Basáñez, María-Gloria

    2010-10-01

    Studying the distribution of parasitic helminth body size across a population of definitive hosts can advance our understanding of parasite population biology. Body size is typically correlated with egg production. Consequently, inequalities in body size have been frequently measured to infer variation in reproductive success (VRS). Body size is also related to parasite age (time since entering the definitive host) and potentially provides valuable information on the mode of acquisition and establishment of immature (larval) parasites within the host: whether parasites tend to establish singly or in aggregates. The mode of acquisition of soil-transmitted helminths has been a theoretical consideration in the parasitological literature but has eluded data-driven investigation. In this paper, we analyse individual Ascaris lumbricoides weight data collected from a cohort of human hosts before and after re-infection following curative treatment, and explore its distribution within and among individuals in the population. Lorenz curves and Gini coefficients indicate that levels of weight inequality (a proxy for VRS) in A.lumbricoides are lower than other published estimates from animal-helminth systems. We explore levels of intra-host weight aggregation using statistical models to estimate the intraclass correlation coefficient (ICC) while adjusting for covariates using a flexible fractional polynomial transformation approach capable of handling non-linear functional relationships. The estimated ICCs indicate that weights are aggregated within hosts both at equilibrium and after re-infection, suggesting that parasites may establish within the host in clumps. The implications of a clumped infection process are discussed in terms of ascariasis transmission dynamics, control and anthelmintic resistance.

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

    Science.gov (United States)

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

    2016-04-01

    of anthelmintic resistance and the presence of hot/dry weather conditions. PMID:26828893

  10. Intrinsic Factors Influencing the Infection by Helminth Parasites in Horses under an Oceanic Climate Area (NW Spain

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    I. Francisco

    2009-01-01

    Full Text Available A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex on the infection by helminth parasites in equine livestock (n=418 under an oceanic climate area (NW Spain was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles and Strongylus and Triodontophorus (large strongyles. The prevalence of gastrointestinal nematode was 89% (95% CI 86, 92 and 1% cestoda (0, 2. The percentage of horses with strongyloid parasites was 89% (86, 92, 11% (8, 14 for Parascaris, and 3% (1, 5 for Oxyuris. The highest prevalence for ascariosis was observed in the youngest horses (10 years animals, and for strongylosis in the 3–10 years ones. Females were significantly more parasitized than males. A negative correlation between the age and the egg-excretion of ascarids and strongyles was recorded. The autochthonous and the English Pure Blood horses were the most parasitized. We concluded that the infections by helminths, especially the strongyloids, are significantly common in the region, so that greater importance should be given to this situation.

  11. Intrinsic Factors Influencing the Infection by Helminth Parasites in Horses under an Oceanic Climate Area (NW Spain).

    Science.gov (United States)

    Francisco, I; Arias, M; Cortiñas, F J; Francisco, R; Mochales, E; Dacal, V; Suárez, J L; Uriarte, J; Morrondo, P; Sánchez-Andrade, R; Díez-Baños, P; Paz-Silva, A

    2009-01-01

    A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex) on the infection by helminth parasites in equine livestock (n = 418) under an oceanic climate area (NW Spain) was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles) and Strongylus and Triodontophorus (large strongyles). The prevalence of gastrointestinal nematode was 89% (95% CI 86, 92) and 1% cestoda (0, 2). The percentage of horses with strongyloid parasites was 89% (86, 92), 11% (8, 14) for Parascaris, and 3% (1, 5) for Oxyuris. The highest prevalence for ascariosis was observed in the youngest horses (10 years animals, and for strongylosis in the 3-10 years ones. Females were significantly more parasitized than males. A negative correlation between the age and the egg-excretion of ascarids and strongyles was recorded. The autochthonous and the English Pure Blood horses were the most parasitized. We concluded that the infections by helminths, especially the strongyloids, are significantly common in the region, so that greater importance should be given to this situation. PMID:20721327

  12. Use of a multiple choice questionnaire to assess UK prescribing channels' knowledge of helminthology and best practice surrounding anthelmintic use in livestock and horses.

    Science.gov (United States)

    Easton, Stephanie; Bartley, David J; Hotchkiss, Emily; Hodgkinson, Jane E; Pinchbeck, Gina L; Matthews, Jacqueline B

    2016-06-01

    Grazing livestock and equines are at risk of infection from a variety of helminths, for which the primary method of control has long been the use of anthelmintics. Anthelmintic resistance is now widespread in a number of helminth species across the globe so it is imperative that best practice control principles be adopted to delay the further spread of resistance. It is the responsibility of all who prescribe anthelmintics (in the UK, this being veterinarians, suitably qualified persons (SQPs) and pharmacists) to provide adequate information on best practice approaches to parasite control at the point of purchase. Poor uptake of best practice guidelines at farm level has been documented; this could be due to a lack of, or inappropriate, advice at the point of anthelmintics purchase. Therefore, the aim here was to evaluate levels of basic knowledge of helminthology, best practice guidelines and dispensing legislation among veterinarians and SQPs in the UK, through a Multiple Choice Question (MCQ) test, that was distributed online via targeted emails and social media sites. For each respondent, the percentage correct was determined (for the MCQ test overall and for subsections) and the results analysed initially using parametric and non-parametric statistics to compare differences between prescribing channels. The results showed that channels generally performed well; veterinarians achieved a mean total percentage correct of 79.7% (range 34.0-100%) and SQPs, a mean total percentage correct of 75.8% (range 38.5-100%) (p=0.051). The analysis indicated that veterinarians performed better in terms of knowledge of basic helminthology (p=0.001), whilst the SQP group performed better on legislation type questions (p=0.032). There was no significant difference in knowledge levels of best practice between the two channels. Multivariable linear regression analysis showed that veterinarians and those answering equine questions only performed significantly better than those

  13. A research agenda for helminth diseases of humans: intervention for control and elimination.

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    Roger K Prichard

    Full Text Available Recognising the burden helminth infections impose on human populations, and particularly the poor, major intervention programmes have been launched to control onchocerciasis, lymphatic filariasis, soil-transmitted helminthiases, schistosomiasis, and cysticercosis. The Disease Reference Group on Helminth Infections (DRG4, established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR, was given the mandate to review helminthiases research and identify research priorities and gaps. A summary of current helminth control initiatives is presented and available tools are described. Most of these programmes are highly dependent on mass drug administration (MDA of anthelmintic drugs (donated or available at low cost and require annual or biannual treatment of large numbers of at-risk populations, over prolonged periods of time. The continuation of prolonged MDA with a limited number of anthelmintics greatly increases the probability that drug resistance will develop, which would raise serious problems for continuation of control and the achievement of elimination. Most initiatives have focussed on a single type of helminth infection, but recognition of co-endemicity and polyparasitism is leading to more integration of control. An understanding of the implications of control integration for implementation, treatment coverage, combination of pharmaceuticals, and monitoring is needed. To achieve the goals of morbidity reduction or elimination of infection, novel tools need to be developed, including more efficacious drugs, vaccines, and/or antivectorial agents, new diagnostics for infection and assessment of drug efficacy, and markers for possible anthelmintic resistance. In addition, there is a need for the development of new formulations of some existing anthelmintics (e.g., paediatric formulations. To achieve ultimate elimination of helminth parasites, treatments for the above mentioned helminthiases, and for taeniasis

  14. Emerging parasitic diseases of sheep.

    Science.gov (United States)

    Taylor, M A

    2012-09-30

    There have been changes in the emergence and inability to control of a number of sheep parasitic infections over the last decade. This review focuses on the more globally important sheep parasites, whose reported changes in epidemiology, occurrence or failure to control are becoming increasingly evident. One of the main perceived driving forces is climate change, which can have profound effects on parasite epidemiology, especially for those parasitic diseases where weather has a direct effect on the development of free-living stages. The emergence of anthelmintic-resistant strains of parasitic nematodes and the increasing reliance placed on anthelmintics for their control, can exert profound changes on the epidemiology of those nematodes causing parasitic gastroenteritis. As a consequence, the effectiveness of existing control strategies presents a major threat to sheep production in many areas around the world. The incidence of the liver fluke, Fasciola hepatica, is inextricably linked to high rainfall and is particularly prevalent in high rainfall years. Over the last few decades, there have also been increasing reports of other fluke associated diseases, such as dicroceliosis and paramphistomosis, in a number of western European countries, possibly introduced through animal movements, and able to establish with changing climates. External parasite infections, such as myiasis, can cause significant economic loss and presents as a major welfare problem. The range of elevated temperatures predicted by current climate change scenarios, result in an elongated blowfly season with earlier spring emergence and a higher cumulative incidence of fly strike. Additionally, legislative decisions leading to enforced changes in pesticide usage and choices have resulted in increased reports and spread of ectoparasitic infections, particularly mite, lice and tick infestations in sheep. Factors, such as dip disposal and associated environmental concerns, and, perhaps more

  15. In vitro ovicidal and larvicidal activity of condensed tannins on gastrointestinal nematode infestations in sheep (Ovis aries

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    Eidi Yoshihara

    2014-12-01

    Full Text Available Infestations of gastrointestinal parasitic nematodes in sheep result in significant costs to farmers. These infestations are controlled using synthetic anthelmintic treatments, which can result in the development of anthelmintic resistance in nematodes. The use of plants rich in condensed tannins (CTs is a promising alternative for controlling infestations of harmful parasites in sheep, and could allow reduction of the chemical products used. This study investigated the in vitro effect of CTs from Acacia mearnsii extract (AE on egg hatching and motility of third-stage larvae. Egg-hatching rate was measured after incubation with extracts for 48 h at 27 °C. The egg hatch test was performed with dilutions of 0.09, 0.19, 0.39, 0.78, 1.56, 3.12, 6.25, 12.5, 25, 50, and 100 mg mL-1. Distilled water was used as the negative control. The corresponding egg hatching inhibition percentages were 22.3, 32.3, 39.2, 49.1, 56.7, 59.0, 62.3, 77.3, 92.7, 98.3, and 100%. The concentration required to inhibit egg hatching in 50% of eggs (LC50 was 2.85 mg mL-1. The inhibition achieved with the negative control was 7.06%. A larval migration inhibition test was carried out after incubation with the extracts for 48 h at 27 oC, with AE and distilled water used in dilutions of 3.12, 6.25, 12.5, 25, 50, and 100 mg mL-1. The corresponding percentages of migration inhibition were 16.5, 37.0, 56.3, 79.4, 91.8, and 97.1%. The concentration required to inhibit migration of 50% of larvae (LC50 was 12.45 mg mL-1. The inhibition achieved with the negative control was 8.53%. The in vitro ovicidal and larvicidal activity of CTs from AE indicate the anthelmintic effect of AE, suggesting the potential of CT extracts to be used as alternatives for controlling gastrointestinal nematode infestations in small ruminants.

  16. Resistance of gastrointestinal nematodes to the most commonly used anthelmintics in sheep, cattle and horses in Spain.

    Science.gov (United States)

    Martínez-Valladares, M; Geurden, T; Bartram, D J; Martínez-Pérez, J M; Robles-Pérez, D; Bohórquez, A; Florez, E; Meana, A; Rojo-Vázquez, F A

    2015-07-30

    The objective of this study was to evaluate the status of anthelmintic resistance (AR) in ruminants and horses in Spain. The efficacy of commonly used macrocyclic lactones (MLs) - ivermectin (IVM) and moxidectin (MOX) - was measured in sheep, cattle and horses. In addition, albendazole (ABZ) and levamisole (LEV) were evaluated in sheep and oxibendazole (OXI) and pyrantel (PYR) in horses. Efficacy was evaluated based on the difference between the arithmetic mean pre- and post-treatment faecal egg count (in cattle and horses), or compared to an untreated control group (in sheep). AR was present when the percentage reduction in egg count was <95% and the lower 95% confidence interval (CI) was <90%; if only one of these two criteria was met, the finding was recorded as suspected AR (SAR). In horses, AR-PYR and OXI was considered when the percentage reduction in egg count was ≤ 90% and the lower 95% CI was ≤ 80%. For each animal species, at least 10 study sites were selected. AR to at least one of the drugs was detected in all 10 sheep flocks; the main parasite identified after treatment was Teladorsagia circumcincta. Moreover, in 5 flocks multidrug resistance was identified, on 4 farms to drugs from different families, on one farm to both MOX and IVM and on another farm to all drugs tested. In cattle, the efficacy of both MOX and IVM was 100% on 4 and 3 farms, respectively, and therefore 60% of these farms were considered to have AR or SAR to both MLs. The most frequent parasite identified after treatment was Trichostrongylus spp., although Ostertagia ostertagi was also identified after treatment on one farm. In contrast to ruminants, the 4 drugs evaluated in horses were highly efficacious against strongyles, with efficacies for the MLs and OXI between 95 and 100% and between 94 and 100% for PYR, although 3 herds were SAR against PYR. In conclusion, AR to at least one of the commonly used drugs was identified on all sheep flocks investigated in the northwest of

  17. Prevalence of drug-resistant gastrointestinal nematodes in an organized sheep farm

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    Ambalathaduvar Meenakshisundaram

    2014-12-01

    Full Text Available Aim: The present study was aimed to determine the resistance against albendazole, fenbendazole, levamisole and closantel in gastrointestinal (GI nematodes of sheep. Introduction: Anthelmintics are used traditionally as an integral part of helminthic control strategies for grazing livestock to prevent production losses from parasitic infections. The continuous and indiscriminate use of the same anthelmintics over years together as the sole means of control are now failing due to the emergence of resistance strains of helminths. Resistance to the commonly used anthelmintics in GI nematodes of sheep has become an increasingly widespread problem throughout the world. Materials and Methods: Fifty-five naturally infected Madras Red lambs of 6-12 months of age were selected and distributed randomly into five treatment groups of 11 animals each. Four groups were treated orally with albendazole (5 mg/kg, fenbendazole (7 mg/kg, levamisole (7.5 mg/kg and closantel (10 mg/kg respectively, whereas the fifth group served as untreated control. Fecal samples were collected per rectum of each lamb just prior to treatment (pre-treatment and on 7, 14, 21 and 28 days post-treatment. The anthelmintic resistance was evaluated by in vivo fecal egg count reduction test (FECRT, post-treatment larval culture and in vitro egg hatch assay. Results: In the FECRT, albendazole reduced the faecal egg count by 86.50%, 84.81%, 85.28% and 84.47% respectively for 4 weeks after treatment. Fecal egg count reduction using fenbendazole was 92.64, 93.04, 90.80 and 90.06% respectively for 4 weeks after treatment. The percent efficacy for levamisole and closantel was more than 95%. The post-treatment larval culture contained only Haemonchus contortus. In the in vitro egg hatch assay, the ED50 value for benzimidazole was 0.299 μg albendazole/ml and levamisole showed an ED50 value of 0.283 μg/ml. Conclusion: Our study confirmed the resistance of H. contortus to benzimidazole in sheep. .

  18. Pooling sheep faecal samples for the assessment of anthelmintic drug efficacy using McMaster and Mini-FLOTAC in gastrointestinal strongyle and Nematodirus infection.

    Science.gov (United States)

    Kenyon, Fiona; Rinaldi, Laura; McBean, Dave; Pepe, Paola; Bosco, Antonio; Melville, Lynsey; Devin, Leigh; Mitchell, Gillian; Ianniello, Davide; Charlier, Johannes; Vercruysse, Jozef; Cringoli, Giuseppe; Levecke, Bruno

    2016-07-30

    In small ruminants, faecal egg counts (FECs) and reduction in FECs (FECR) are the most common methods for the assessment of intensity of gastrointestinal (GI) nematodes infections and anthelmintic drug efficacy, respectively. The main limitation of these methods is the time and cost to conduct FECs on a representative number of individual animals. A cost-saving alternative would be to examine pooled faecal samples, however little is known regarding whether pooling can give representative results. In the present study, we compared the FECR results obtained by both an individual and a pooled examination strategy across different pool sizes and analytical sensitivity of the FEC techniques. A survey was conducted on 5 sheep farms in Scotland, where anthelmintic resistance is known to be widespread. Lambs were treated with fenbendazole (4 groups), levamisole (3 groups), ivermectin (3 groups) or moxidectin (1 group). For each group, individual faecal samples were collected from 20 animals, at baseline (D0) and 14 days after (D14) anthelmintic administration. Faecal samples were analyzed as pools of 3-5, 6-10, and 14-20 individual samples. Both individual and pooled samples were screened for GI strongyle and Nematodirus eggs using two FEC techniques with three different levels of analytical sensitivity, including Mini-FLOTAC (analytical sensitivity of 10 eggs per gram of faeces (EPG)) and McMaster (analytical sensitivity of 15 or 50 EPG).For both Mini-FLOTAC and McMaster (analytical sensitivity of 15 EPG), there was a perfect agreement in classifying the efficacy of the anthelmintic as 'normal', 'doubtful' or 'reduced' regardless of pool size. When using the McMaster method (analytical sensitivity of 50 EPG) anthelmintic efficacy was often falsely classified as 'normal' or assessment was not possible due to zero FECs at D0, and this became more pronounced when the pool size increased. In conclusion, pooling ovine faecal samples holds promise as a cost-saving and efficient

  19. Partial characterization of superoxide dismutase activity in the Barber pole worm-Haemonchus contortus infecting Capra hircus and abomasal tissue extracts

    Institute of Scientific and Technical Information of China (English)

    Sadia; Rashid; Malik; Irshadullah

    2014-01-01

    Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD.Methods:The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method.Results:The adult females were found to have higher enzyme activity than the male worms.Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites.The SOD activity was negatively correlated to the worm burden.Statistically significant decrease in SOD activity(P<0.05) was observed in the heavily infected host tissue in comparison to the control non-infected host tissue.SOD profile of the crude extracts of both the sexes revealed polymorphism and a fast migrating activity band being characteristic of E/S products.The SOD activities were found highly sensitive to potassium cyanide indicating the Cu/Zn form of SOD.Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery.The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack.SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world.The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential.One characteristic SOD band was found in the females which was not present in any other preparations and thus could

  20. Dissemination of parasites by animal movements in small ruminant farms.

    Science.gov (United States)

    Vasileiou, N G C; Fthenakis, G C; Papadopoulos, E

    2015-09-30

    The present paper discusses the spread of parasites by animal movements in small ruminant farms; it focuses in dissemination of parasitic forms that would lead to subsequent infection of sheep or goats. Systems of small ruminant production involve a component of animal movement (e.g., grazing) as part of routine husbandry, which favors spread of parasitic forms; that refers mainly to parasites of the digestive system (nematodes, trematodes, cestodes, protozoa), as well as helminthes of the respiratory system, although dissemination of the various parasitic forms in the environment would not always result to subsequent infection; external parasites may also be disseminated during movements, e.g., to inhabit wooden poles used in fencing. New livestock into a farm constitutes a biosecurity hazard and the most common means to introducing new parasitic pathogens into a farm; in contemporary small ruminant health management, this contributes in dissemination of anthelmintic resistant parasitic strains; other parasitic disease agents (e.g., mange mites, ticks) may also be spread into a farm that way. Often, especially in small scale farming, visits of rams or bucks take place from one farm to another during the mating season; in such cases, ectoparasites (e.g., mange mites) can be disseminated through direct contact of animals, as well other pathogens (e.g., Toxoplasma gondii, Neospora caninum) via the semen. During transportation of sheep/goats, parasitic forms can also spread, as well as during movement of sheep or goats to slaughterhouses, in which case dogs present in these places would contribute to their dissemination. Spread of life forms of various parasites can also occur from animal species present in the environment of sheep or goats; these include animals present within a farm, stray dogs roaming around a farm (e.g., for spread of Multiceps multiceps, Echinococcus granulosus, Taenia hydatigena, N. caninum), cats commanding the environment of a farm (e.g., for

  1. Epidemiological Intelligence for Grazing Management in Strategic Control of Parasitic Gastroenteritis in Small Ruminants in India AND#8211; A Review

    Directory of Open Access Journals (Sweden)

    Sadaf Bukhari and Prabir Kumar Sanyal

    2011-04-01

    Full Text Available Because of the environmental and consumer concerns arising out of exponential growth in human population the world over, a term Sustainable Development has become an integral international concept, which is defined as one which meets the needs of the present without compromising the ability of future generations to meet their own needs. Ruminant animals appear sustainable as they do not compete with man for food, play a crucial role in the conversion of low quality plant material and crop residues to high quality human food as well as return valuable plant nutrients to the soil. Parasite control in ruminant livestock is a first-order input in any sustainable animal production system. As sustainable development is a compromise between reducing environmental degradation and positive economic growth, sustainable parasite control should aim towards less intensive, lower input, lesser risk of parasite induced losses with greater opportunities for integration of all available control resources. The compound scenario of rising anthelmintic resistance, food and environmental security and apathy of the pharmaceutical industry to go for the invention of new anthelmintic compounds has triggered the need for optimising the use of available anthelmintics with integration of all other alternative means for sustainable worm control. The “Sustainable Control of Parasitic Gastroenteritis in Ruminants” is thus encompasses a multidisciplinary approach involving integration of chemotherapy, grazing management, biological control, worm vaccines, genetic resistance of hosts, mathematical model based decision support and other strategies, if any. There is no single requirement more crucial to the rational and sustainable control of helminth parasites in grazing animals than a comprehensive knowledge of the epidemiology of the parasite as it interacts with the host in a specific climatic, management and production environment. In its absence, anthelmintic treatment

  2. Breeding for resistance to gastrointestinal nematodes - the potential in low-input/output small ruminant production systems.

    Science.gov (United States)

    Zvinorova, P I; Halimani, T E; Muchadeyi, F C; Matika, O; Riggio, V; Dzama, K

    2016-07-30

    The control of gastrointestinal nematodes (GIN) is mainly based on the use of drugs, grazing management, use of copper oxide wire particles and bioactive forages. Resistance to anthelmintic drugs in small ruminants is documented worldwide. Host genetic resistance to parasites, has been increasingly used as a complementary control strategy, along with the conventional intervention methods mentioned above. Genetic diversity in resistance to GIN has been well studied in experimental and commercial flocks in temperate climates and more developed economies. However, there are very few report outputs from the more extensive low-input/output smallholder systems in developing and emerging countries. Furthermore, results on quantitative trait loci (QTL) associated with nematode resistance from various studies have not always been consistent, mainly due to the different nematodes studied, different host breeds, ages, climates, natural infections versus artificial challenges, infection level at sampling periods, among others. The increasing use of genetic markers (Single Nucleotide Polymorphisms, SNPs) in GWAS or the use of whole genome sequence data and a plethora of analytic methods offer the potential to identify loci or regions associated nematode resistance. Genomic selection as a genome-wide level method overcomes the need to identify candidate genes. Benefits in genomic selection are now being realised in dairy cattle and sheep under commercial settings in the more advanced countries. However, despite the commercial benefits of using these tools, there are practical problems associated with incorporating the use of marker-assisted selection or genomic selection in low-input/output smallholder farming systems breeding schemes. Unlike anthelmintic resistance, there is no empirical evidence suggesting that nematodes will evolve rapidly in response to resistant hosts. The strategy of nematode control has evolved to a more practical manipulation of host-parasite equilibrium

  3. RNAi dynamics in Juvenile Fasciola spp. Liver flukes reveals the persistence of gene silencing in vitro.

    Directory of Open Access Journals (Sweden)

    Paul McVeigh

    2014-09-01

    Full Text Available Fasciola spp. liver fluke cause pernicious disease in humans and animals. Whilst current control is unsustainable due to anthelmintic resistance, gene silencing (RNA interference, RNAi has the potential to contribute to functional validation of new therapeutic targets. The susceptibility of juvenile Fasciola hepatica to double stranded (dsRNA-induced RNAi has been reported. To exploit this we probe RNAi dynamics, penetrance and persistence with the aim of building a robust platform for reverse genetics in liver fluke. We describe development of standardised RNAi protocols for a commercially-available liver fluke strain (the US Pacific North West Wild Strain, validated via robust transcriptional silencing of seven virulence genes, with in-depth experimental optimisation of three: cathepsin L (FheCatL and B (FheCatB cysteine proteases, and a σ-class glutathione transferase (FheσGST.Robust transcriptional silencing of targets in both F. hepatica and Fasciola gigantica juveniles is achievable following exposure to long (200-320 nt dsRNAs or 27 nt short interfering (siRNAs. Although juveniles are highly RNAi-susceptible, they display slower transcript and protein knockdown dynamics than those reported previously. Knockdown was detectable following as little as 4h exposure to trigger (target-dependent and in all cases silencing persisted for ≥25 days following long dsRNA exposure. Combinatorial silencing of three targets by mixing multiple long dsRNAs was similarly efficient. Despite profound transcriptional suppression, we found a significant time-lag before the occurrence of protein suppression; FheσGST and FheCatL protein suppression were only detectable after 9 and 21 days, respectively.In spite of marked variation in knockdown dynamics, we find that a transient exposure to long dsRNA or siRNA triggers robust RNAi penetrance and persistence in liver fluke NEJs supporting the development of multiple-throughput phenotypic screens for control

  4. Breeding for resistance to gastrointestinal nematodes - the potential in low-input/output small ruminant production systems.

    Science.gov (United States)

    Zvinorova, P I; Halimani, T E; Muchadeyi, F C; Matika, O; Riggio, V; Dzama, K

    2016-07-30

    The control of gastrointestinal nematodes (GIN) is mainly based on the use of drugs, grazing management, use of copper oxide wire particles and bioactive forages. Resistance to anthelmintic drugs in small ruminants is documented worldwide. Host genetic resistance to parasites, has been increasingly used as a complementary control strategy, along with the conventional intervention methods mentioned above. Genetic diversity in resistance to GIN has been well studied in experimental and commercial flocks in temperate climates and more developed economies. However, there are very few report outputs from the more extensive low-input/output smallholder systems in developing and emerging countries. Furthermore, results on quantitative trait loci (QTL) associated with nematode resistance from various studies have not always been consistent, mainly due to the different nematodes studied, different host breeds, ages, climates, natural infections versus artificial challenges, infection level at sampling periods, among others. The increasing use of genetic markers (Single Nucleotide Polymorphisms, SNPs) in GWAS or the use of whole genome sequence data and a plethora of analytic methods offer the potential to identify loci or regions associated nematode resistance. Genomic selection as a genome-wide level method overcomes the need to identify candidate genes. Benefits in genomic selection are now being realised in dairy cattle and sheep under commercial settings in the more advanced countries. However, despite the commercial benefits of using these tools, there are practical problems associated with incorporating the use of marker-assisted selection or genomic selection in low-input/output smallholder farming systems breeding schemes. Unlike anthelmintic resistance, there is no empirical evidence suggesting that nematodes will evolve rapidly in response to resistant hosts. The strategy of nematode control has evolved to a more practical manipulation of host-parasite equilibrium

  5. Biphasic appearance of corticated and decorticated ascarid egg shedding in untreated horse foals.

    Science.gov (United States)

    Donoghue, E M; Lyons, E T; Bellaw, J L; Nielsen, M K

    2015-11-30

    Parascaris spp. infects foals worldwide and may cause airway inflammation in addition to small intestinal impaction and rupture. It is observed that acquired immunity eliminates ascarid burdens beginning at about 6 months of age, and current evidence suggests that a single parasite generation propagates in each foal crop. The purpose of this study was to monitor natural parasitic infections in untreated mixed breed horse foals over the course of 0-300 days of age. Fecal samples were collected monthly from all foals born in 2014 (n=13), beginning July 2014 through February 2015. Fecal egg counts (FECs) were performed in triplicates using the Mini-FLOTAC method. The foals were necropsied between 154 and 298 days of age and all intestinal ascarid were collected and identified to stage. Ascarid FECs exhibited a biphasic distribution with an initial peak at 91-120 days of age and, after a steady decline, a second, smaller peak at 241-300 days of age. Numbers of corticated and decorticated ascarid eggs were compared, with decorticated FECs remaining consistently low with a slight increase directly after the first corticated FEC peak. Overall, 4.36% of the total ascarid eggs counted were decorticated. Ascarid FECs showed a sharp peak in September, declined, and then steadily increased beginning in December and continuing through February. Upon necropsy, moderate to high number of ascarid specimens were recovered from foals between 8 and 10 months of age, coinciding with the second peak for the FECs. Eleven of the 13 foals harbored immature ascarid stages indicating a recent reinfection. However, these data demonstrates that apparently a second, smaller wave of infection is present in 8-10 month old foals. It may be of value to monitor egg counts in this age group to make sure that all parasite categories are well controlled.

  6. Accelerated decolorization of reactive azo dyes under saline conditions by bacteria isolated from Arabian seawater sediment.

    Science.gov (United States)

    Khalid, Azeem; Kausar, Farzana; Arshad, Muhammad; Mahmood, Tariq; Ahmed, Iftikhar

    2012-12-01

    Presence of huge amount of salts in the wastewater of textile dyeing industry is one of the major limiting factors in the development of an effective biotreatment system for the removal of azo dyes from textile effluents. Bacterial spp. capable of thriving under high salt conditions could be employed for the treatment of saline dyecontaminated textile wastewaters. The present study was aimed at isolating the most efficient bacterial strains capable of decolorizing azo dyes under high saline conditions. Fiftyeight bacterial strains were isolated from seawater, seawater sediment, and saline soil, using mineral salt medium enriched with 100 mg l−1 Reactive Black-5 azo dye and 50 g NaCl l−1 salt concentration. Bacterial strains KS23 (Psychrobacter alimentarius) and KS26 (Staphylococcus equorum) isolated from seawater sediment were able to decolorize three reactive dyes including Reactive Black 5, Reactive Golden Ovifix, and Reactive Blue BRS very efficiently in liquid medium over a wide range of salt concentration (0-100 g NaCl l)⁻¹. Time required for complete decolorization of 100 mg dye l ⁻¹ varied with the type of dye and salt concentration. In general, there was an inverse linear relationship between the velocity of the decolorization reaction (V) and salt concentration. This study suggested that bacteria isolated from saline conditions such as seawater sediment could be used in designing a bioreactor for the treatment of textile effluent containing high concentration of salts.

  7. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp.

  8. Molecular detection and sensitivity to antibiotics and bacteriocins of pathogens isolated from bovine mastitis in family dairy herds of central Mexico.

    Science.gov (United States)

    León-Galván, Ma Fabiola; Barboza-Corona, José E; Lechuga-Arana, A Arianna; Valencia-Posadas, Mauricio; Aguayo, Daniel D; Cedillo-Pelaez, Carlos; Martínez-Ortega, Erika A; Gutierrez-Chavez, Abner J

    2015-01-01

    Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DM (P Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study. PMID:25815326

  9. Molecular Detection and Sensitivity to Antibiotics and Bacteriocins of Pathogens Isolated from Bovine Mastitis in Family Dairy Herds of Central Mexico

    Directory of Open Access Journals (Sweden)

    Ma. Fabiola León-Galván

    2015-01-01

    Full Text Available Thirty-two farms (n=535 cows located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM and clinical mastitis (CLM were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT (≥3 and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY, lactation number (LN, herd size (HS, and number of days in milk (DM were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH, LN, HS, and DM P<0.01, and correlations between udder quarters from the CMT were around 0.49 P<0.01. Coagulase-negative staphylococci were mainly identified, as well as Staphylococcus aureus, Streptococcus uberis, Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study.

  10. Automated ribotyping to distinguish the different non Sau/ non Sep staphylococcal emerging pathogens in orthopedic implant infections.

    Science.gov (United States)

    Campoccia, D; Baldassarri, L; An, Y H; Kang, Q K; Pirini, V; Gamberini, S; Pegreffi, F; Montanaro, L; Arciola, C R

    2006-04-01

    Several species belonging to Staphylococcus genus, other than Staphylococcus aureus and Staphylococcus epidermidis (non Sau/ non Sep species), exhibit increasing abilities as opportunistic pathogens in the colonisation of periprosthetic tissues. Consequently, the availability of means for accurate identification is crucial to assess the pathogenic characteristics and to clarify clinical relevance of the individual species. Here, 146 clinical staphylococcal isolates belonging to non Sau/ non Sep species from prosthesis-associated orthopedic infections were analyzed by conventional enzymatic galleries and by automated ribotyping. Twelve different species were recognised: S. capitis, S. caprae, S. cohnii, S. equorum, S. haemolyticus, S. hominis, S. lugdunensis, S. pasteuri, S. sciuri, S. simulans, S. warneri, S. xylosus. Ribotype identifications were compared with the phenotypes obtained by the Api 20 Staph system and/or ID 32 Staph system. ID 32 Staph profiles were more consistent with ribotyping results than Api Staph profiles. Across the different staphylococcal species investigated, correct identifications with Api Staph were 45%, while with ID 32 Staph they were 59%. It has, however, to be mentioned that ID 32 Staph was mostly applied to discriminate unmatched ribotyping and Api Staph identifications, thus to a subpopulation of strains with "atypical" metabolic profile. Automated ribotyping provided a correct identification for 91% of the isolates. These results confirm automated ribotyping as a convenient rapid technique, still subject to improvements, which will accurately and rapidly recognise the newly emerging staphylococcal pathogens in implant-related orthopedic infections. PMID:16705611

  11. [The role of bacterial contamination of milking utensils and disinfecting solutions as a possible cause of clinical mastitis in dairy cows].

    Science.gov (United States)

    Hässig, M; Sigrist, S M; Corti, S; Giezendanner, N; Stephan, R

    2011-06-01

    Various instruments and utensils used during milking as well as teat dip solutions were examined for contamination with coagulase-negative staphylococci (CNS). The goal of this study was to investigate the relationship between contaminated fomites and udder infection in dairy cows. A total of 344 cows from ten dairy farms with the highest rate of clinical mastitis among the farms serviced by the Ambulatory Clinic of the University of Zurich were included in the study. Each farm was visited five times. All lactating cows, with the exception of those undergoing antibiotic treatment, were examined immediately before milking using the California Mastitis Test (CMT). A milk sample was collected from positive quarters. Items used to clean the udder, which included wood wool, paper towels and disinfecting towels as well as the milker's hands and the teat dip cup were swabbed for bacteriological examination. Water samples, samples of teat dip and cleaning solutions were also collected and cultured. Our results demonstrate that cleaning and disinfecting solutions have the potential to transmit udder pathogens and cause clinical mastitis. The most common CNS isolated from quarter samples were S. saprophyticus, S. sciuri and S. chromogenes, and the most common CNS isolated from utensils, cleaning and disinfecting solutions were S. fleuretii, S. vitulus, S. equorum, S. sciuri, S. haemolyticus, S. succinus and S. saprophyticus. PMID:21638262

  12. Microbiological changes and biodiversity of cultivable indigenous bacteria in Sanbao larger yellow croaker (Pseudosciaena crocea), a Chinese salted and fermented seafood.

    Science.gov (United States)

    Zhang, He; Li, Yan; Xu, Kunhua; Wu, Jiajia; Dai, Zhiyuan

    2015-04-01

    Sanbao large yellow croaker is a kind of Chinese salted and fermented seafood processed by adding 50% of salt and fermenting at high temperature [around 30 °C] over 20 d. To get a comprehensive understanding of cultivable microorganism's diversity present in its fermentation, the chemical and microbial properties of this product, were detected initially, followed by identification of bacteria recovered from different fermentation periods using PCR-RFLP and 16S rRNA gene sequencing analysis. In total, 105 indigenous isolates were recovered with 3 different medium and majority of the isolates picked up from both MRS and MSA medium were finally clustered into the genus of Staphylococcus (S.). Among the 90 Staphylococci, S. xylosus, S. saprophyticus, and S. nepalensis were the most prevailing cultivable species recovered throughout the whole production process (70 isolates, 77.8%), while 5 other species, namely, S. aureus, S. vitulinus, S. sciuri, S. equorum, and S. succinus formed a minor fraction (20 isolates, 22.2%) of the Staphylococcus communities. Lactic acid bacteria, Pseudomonas, Proteus, and Bacillus constituted trivial populations in the initial period of the fermentation and then gave the way to the Staphylococcus immediately. High salt concentration used during the processing is like to have a pronounced influence on the microbial populations involved. Data obtained in this work could be referred in control and optimization of the fermentation process and selecting suitable strains for aquatic product fermentation.

  13. Identification of Staphylococcus spp. using (GTG)₅-PCR fingerprinting.

    Science.gov (United States)

    Svec, Pavel; Pantůček, Roman; Petráš, Petr; Sedláček, Ivo; Nováková, Dana

    2010-12-01

    A group of 212 type and reference strains deposited in the Czech Collection of Microorganisms (Brno, Czech Republic) and covering 41 Staphylococcus species comprising 21 subspecies was characterised using rep-PCR fingerprinting with the (GTG)₅ primer in order to evaluate this method for identification of staphylococci. All strains were typeable using the (GTG)₅ primer and generated PCR products ranging from 200 to 4500 bp. Numerical analysis of the obtained fingerprints revealed (sub)species-specific clustering corresponding with the taxonomic position of analysed strains. Taxonomic position of selected strains representing the (sub)species that were distributed over multiple rep-PCR clusters was verified and confirmed by the partial rpoB gene sequencing. Staphylococcus caprae, Staphylococcus equorum, Staphylococcus sciuri, Staphylococcus piscifermentans, Staphylococcus xylosus, and Staphylococcus saprophyticus revealed heterogeneous fingerprints and each (sub)species was distributed over several clusters. However, representatives of the remaining Staphylococcus spp. were clearly separated in single (sub)species-specific clusters. These results showed rep-PCR with the (GTG)₅ primer as a fast and reliable method applicable for differentiation and straightforward identification of majority of Staphylococcus spp.

  14. Aspartate inhibits Staphylococcus aureus biofilm formation.

    Science.gov (United States)

    Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

    2015-04-01

    Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. PMID:25687923

  15. Microbiological changes and biodiversity of cultivable indigenous bacteria in Sanbao larger yellow croaker (Pseudosciaena crocea), a Chinese salted and fermented seafood.

    Science.gov (United States)

    Zhang, He; Li, Yan; Xu, Kunhua; Wu, Jiajia; Dai, Zhiyuan

    2015-04-01

    Sanbao large yellow croaker is a kind of Chinese salted and fermented seafood processed by adding 50% of salt and fermenting at high temperature [around 30 °C] over 20 d. To get a comprehensive understanding of cultivable microorganism's diversity present in its fermentation, the chemical and microbial properties of this product, were detected initially, followed by identification of bacteria recovered from different fermentation periods using PCR-RFLP and 16S rRNA gene sequencing analysis. In total, 105 indigenous isolates were recovered with 3 different medium and majority of the isolates picked up from both MRS and MSA medium were finally clustered into the genus of Staphylococcus (S.). Among the 90 Staphylococci, S. xylosus, S. saprophyticus, and S. nepalensis were the most prevailing cultivable species recovered throughout the whole production process (70 isolates, 77.8%), while 5 other species, namely, S. aureus, S. vitulinus, S. sciuri, S. equorum, and S. succinus formed a minor fraction (20 isolates, 22.2%) of the Staphylococcus communities. Lactic acid bacteria, Pseudomonas, Proteus, and Bacillus constituted trivial populations in the initial period of the fermentation and then gave the way to the Staphylococcus immediately. High salt concentration used during the processing is like to have a pronounced influence on the microbial populations involved. Data obtained in this work could be referred in control and optimization of the fermentation process and selecting suitable strains for aquatic product fermentation. PMID:25874648

  16. Characterization and Technological Features of Autochthonous Coagulase-Negative Staphylococci as Potential Starters for Portuguese Dry Fermented Sausages.

    Science.gov (United States)

    Semedo-Lemsaddek, Teresa; Carvalho, Laura; Tempera, Carolina; Fernandes, Maria H; Fernandes, Maria J; Elias, Miguel; Barreto, António S; Fraqueza, Maria J

    2016-05-01

    The manufacture of dry fermented sausages is an important part of the meat industry in Southern European countries. These products are usually produced in small shops from a mixture of pork, fat, salt, and condiments and are stuffed into natural casings. Meat sausages are slowly cured through spontaneous fermentation by autochthonous microbiota present in the raw materials or introduced during manufacturing. The aim of this work was to evaluate the technological and safety features of coagulase-negative staphylococci (CNS) isolated from Portuguese dry fermented meat sausages in order to select autochthonous starters. Isolates (n = 104) obtained from 2 small manufacturers were identified as Staphylococcus xylosus, Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus carnosus. Genomically diverse isolates (n = 82) were selected for further analysis to determine the ability to produce enzymes (for example, nitrate-reductases, proteases, lipases) and antibiotic susceptibility. Autochthonous CNS producing a wide range of enzymes and showing low antibioresistance were selected as potential starters for future use in the production of dry fermented meat sausages. PMID:27095684

  17. Intramammary infection with coagulase-negative staphylococci at parturition: Species-specific prevalence, risk factors, and effect on udder health.

    Science.gov (United States)

    De Visscher, A; Piepers, S; Haesebrouck, F; De Vliegher, S

    2016-08-01

    Coagulase-negative staphylococci (CNS) are the main cause of bovine intramammary infections (IMI) in many countries. Despite a high prevalence of CNS IMI at parturition, species-specific risk factor studies, relying on accurate identification methods, are lacking. Therefore, this observational study aimed at determining the prevalence and distribution of different CNS species causing IMI in fresh heifers and dairy cows in Flemish dairy herds and identifying associated species- and subgroup-specific risk factors at the herd, cow, and quarter level. The effect on udder health was investigated as well. Staphylococcus chromogenes, S. sciuri, and S. cohnii were the most frequently isolated species. The only CNS species causing IMI in fresh heifers and dairy cows in all herds was Staphylococcus chromogenes, whereas large between-herd differences in distribution were observed for the other species. Quarters from heifers and quarters with an inverted teat end had higher odds of being infected with S. chromogenes, S. simulans, or S. xylosus as well as with S. chromogenes solely. Prepartum teat apex colonization with S. chromogenes increased the likelihood of S. chromogenes IMI in the corresponding quarters at parturition. Quarters with dirty teat apices before calving were more likely to be infected with S. cohnii, S. equorum, S. saprophyticus, or S. sciuri, supporting the environmental nature of these CNS species. Three species (S. chromogenes, S. simulans, and S. xylosus) were associated with a higher quarter somatic cell count at parturition as compared with uninfected quarters. PMID:27236763

  18. Survival of cheese-ripening microorganisms in a dynamic simulator of the gastrointestinal tract.

    Science.gov (United States)

    Adouard, Nadège; Magne, Laurent; Cattenoz, Thomas; Guillemin, Hervé; Foligné, Benoît; Picque, Daniel; Bonnarme, Pascal

    2016-02-01

    A mixture of nine microorganisms (six bacteria and three yeasts) from the microflora of surface-ripened cheeses were subjected to in vitro digestive stress in a three-compartment "dynamic gastrointestinal digester" (DIDGI). We studied the microorganisms (i) grown separately in culture medium only (ii) grown separately in culture medium and then mixed, (iii) grown separately in culture medium and then included in a rennet gel and (iv) grown together in smear-ripened cheese. The yeasts Geotrichum candidum, Kluyveromyces lactis and Debaryomyces hansenii, were strongly resistant to the whole DIDGI process (with a drop in viable cell counts of less than cheese-grown cultures. Ripening bacteria such as Hafnia alvei survived gastric stress less well when grown in cheese (with no viable cells after 90 min of exposure of the cheese matrix, compared with 6 CFU mL(-1) in lab cultures). The ability of Corynebacterium casei and Staphylococcus equorum to withstand digestive stress was similar for cheese and pure culture conditions. When grow in a cheese matrix, Brevibacterium aurantiacum and Arthrobacter arilaitensis were clearly more sensitive to the overall digestive process than when grown in pure cultures. Lactococcus lactis displayed poorer survival in gastric and duodenal compartments when it had been grown in cheese. In vivo experiments in BALB/c mice agreed with the DIDGI experiments and confirmed the latter's reliability.

  19. Isolation, identification and characteristics of moderately halophilic bacteria in crab paste%蟹酱中度嗜盐菌的分离、鉴定及特性研究

    Institute of Scientific and Technical Information of China (English)

    吕彦; 孙业盈

    2012-01-01

    The aim of this study was to isolate and identify moderately halophilic bacteria from crab paste and investigate its morphological, physiological and biochemical characteristics. Three moderately halophilic bacteria PKY101, PKY102 and PKY103 were isolated. Moderately halophilic bacteria were isolated by Gibbons medium. Morphological tests, biochemical reactions and molecular identifications of 16S rDNA were applied to i-dentify the bacteria with determining growth characterization by spectrophotometry. Three strains were found to be gram-positive, non-sporulating and spherical, and the diameter of the strains was 0.6μm~1.9μm, 0.8μm ~1.0μm and 0.7μm~1.5μm, respectively. 16S rDNA alignment and phylo-genetic anlysis showed that the stain PKY101 had a 99% homology with Staphylococcus succinus, PKY102 had a 99% homology with Staphylococ-cus cohnii and PKY103 had a 99% homology with Staphylococcus equorum. Our result could provided some references for study of halophilic bacteria structure in crab paste and prevention of halophilic bacteria contamination.%从蟹酱中分离纯化鉴定嗜盐菌,对其进行形态学和生理生化特性研究.采用Gibbons培养基分离纯化,通过形态学、生理生化实验进行特性研究,16S rDNA序列比对分析进行鉴定,吸光度法测定生长特性.结果分离得到3株中度嗜盐菌PKY101,PKY102和PKY103,试验结果表明,3种嗜盐菌均为革兰氏阳性菌,不产芽孢,菌体呈球状,直径分别为0.6μm~1.9μm,0.8μm~1.0μm,0.7μm~1.5μm;系统发育分析将3株嗜盐菌鉴定为葡萄球菌属(Staphylococcus)中的3个不同的种,分别为:琥珀葡萄球菌(Staphylococcus succinus)、科氏葡萄球菌(Staphylococcus cohnii)和马胃葡萄球菌(Staphylococcus equorum).本研究将为进一步研究蟹酱中的嗜盐菌的类型及在发酵盐渍类食品中的作用开展了前期的基础工作,为防止嗜盐菌污染食品提供了理论参考.

  20. Microbial background flora in small-scale cheese production facilities does not inhibit growth and surface attachment of Listeria monocytogenes.

    Science.gov (United States)

    Schirmer, B C T; Heir, E; Møretrø, T; Skaar, I; Langsrud, S

    2013-10-01

    The background microbiota of 5 Norwegian small-scale cheese production sites was examined and the effect of the isolated strains on the growth and survival of Listeria monocytogenes was investigated. Samples were taken from the air, food contact surfaces (storage surfaces, cheese molds, and brine) and noncontact surfaces (floor, drains, and doors) and all isolates were identified by sequencing and morphology (mold). A total of 1,314 isolates were identified and found to belong to 55 bacterial genera, 1 species of yeast, and 6 species of mold. Lactococcus spp. (all of which were Lactococcus lactis), Staphylococcus spp., Microbacterium spp., and Psychrobacter sp. were isolated from all 5 sites and Rhodococcus spp. and Chryseobacterium spp. from 4 sites. Thirty-two genera were only found in 1 out of 5 facilities each. Great variations were observed in the microbial background flora both between the 5 producers, and also within the various production sites. The greatest diversity of bacteria was found in drains and on rubber seals of doors. The flora on cheese storage shelves and in salt brines was less varied. A total of 62 bacterial isolates and 1 yeast isolate were tested for antilisterial activity in an overlay assay and a spot-on-lawn assay, but none showed significant inhibitory effects. Listeria monocytogenes was also co-cultured on ceramic tiles with bacteria dominating in the cheese production plants: Lactococcus lactis, Pseudomonas putida, Staphylococcus equorum, Rhodococcus spp., or Psychrobacter spp. None of the tested isolates altered the survival of L. monocytogenes on ceramic tiles. The conclusion of the study was that no common background flora exists in cheese production environments. None of the tested isolates inhibited the growth of L. monocytogenes. Hence, this study does not support the hypothesis that the natural background flora in cheese production environments inhibits the growth or survival of L. monocytogenes. PMID:23891302

  1. Cultivation-independent analysis of microbial communities on Austrian raw milk hard cheese rinds.

    Science.gov (United States)

    Schornsteiner, Elisa; Mann, Evelyne; Bereuter, Othmar; Wagner, Martin; Schmitz-Esser, Stephan

    2014-06-16

    "Vorarlberger Bergkäse" (VB) is an Austrian artisanal hard cheese produced from raw cow's milk. The composition of its rind microbiota and the changes in the microbial communities during ripening have not previously been investigated. This study used 16S and 18S rRNA gene cloning and sequencing to characterize the bacterial and fungal communities of seven pooled cheese rind samples taken in seven different ripening cellars of three Austrian dairy facilities. A total of 408 clones for 16S and 322 clones for 18S rRNA gene libraries were used for taxonomic classification, revealing 39 bacterial and seven fungal operational taxonomic units (OTUs). Bacterial OTUs belonged to four different phyla. Most OTUs were affiliated to genera often found in cheese, including high numbers of coryneforms. The most abundant OTU from 16S rRNA gene libraries showed highest similarity to Halomonas. Young cheese rinds were dominated by Actinobacteria or Proteobacteria, particularly by Halomonas and Brevibacterium aurantiacum, while Staphyloccocus equorum was most abundant in old cheeses. The most abundant 18S rRNA OTU had highest similarity to the filamentous fungus Scopulariopsis brevicaulis. Pairwise correlation analyses revealed putative co-occurrences between a number of OTUs. It was possible to discriminate the different cheese rind microbiota at the community-level by facility affiliation and ripening time. This work provides insights into the microbial composition of VB cheese rinds and might allow the processing- and ripening conditions to be improved to enhance the quality of the product. PMID:24794620

  2. Characterization of coagulase-negative staphylococcus species from cows' milk and environment based on bap, icaA, and mecA genes and phenotypic susceptibility to antimicrobials and teat dips.

    Science.gov (United States)

    Piessens, V; De Vliegher, S; Verbist, B; Braem, G; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; Van Coillie, E

    2012-12-01

    The aim of this study was to investigate whether the main coagulase-negative staphylococci (CNS) species involved in bovine intramammary infections (IMI) possess specific characteristics that promote colonization of the udder. Virulence markers associated with biofilm formation, antimicrobial resistance, and biocide tolerance were compared between typically contagious CNS species (Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, and Staphylococcus simulans) and those rarely causing IMI (Staphylococcus sciuri, Staphylococcus equorum, and others) to find possible associations with pathogenicity. Coagulase-negative staphylococci isolates (n=366) belonging to 22 different species were analyzed by PCR for the presence of the biofilm-associated genes bap and icaA, and the methicillin resistance gene mecA. A selection of 82 isolates was additionally tested for their susceptibility to 5 antibiotics and 2 commercial teat dip products. Minimum inhibitory concentrations of antimicrobials were determined by Etest (AB bioMérieux, Marcy l'Etoile, France), and a microdilution method was optimized to determine minimum biocidal concentrations of teat dips. The bap, icaA, and mecA genes were detected significantly more in isolates from CNS species typically living in the cows' environment than in isolates from IMI-causing species. Antimicrobial resistance was mainly against erythromycin (23%) or oxacillin (16%), and was detected more often in the environmental species. The isolates least susceptible to the teat dips belonged to the IMI-causing species Staph. chromogenes and Staph. simulans. We concluded that carriage of biofilm genes and antimicrobial resistance were not associated with the ability to colonize the mammary gland because free-living CNS species constituted a more significant reservoir of biofilm and resistance determinants than did IMI-causing species. In contrast, increased tolerance to biocides may favor the establishment of

  3. Application of different molecular techniques for characterization of catalase-positive cocci isolated from sucuk.

    Science.gov (United States)

    Kesmen, Zülal; Yarimcam, Burcu; Aslan, Hakiye; Ozbekar, Esra; Yetim, Hasan

    2014-02-01

    This study was carried out for the characterization and discrimination of the indigenous Gram positive, catalase-positive cocci (GCC) population in sucuk, a traditional Turkish dry-fermented sausage. Sucuk samples, produced by the traditional method without starter culture were collected from 8 local producers in Kayseri/Turkey and a total of 116 GCC isolates were identified by using different molecular techniques. Two different molecular fingerprinting methods; namely, randomly amplified polymorphic DNA-PCR (RAPD-PCR) and repetitive extragenic palindrome-PCR (rep-PCR), were used for the clustering of isolates and identification at species level was carried out by full length sequencing of 16S rDNA. Combining the results obtained from molecular fingerprinting and 16S rDNA sequencing showed that the dominant GCC species isolated from the sucuk samples was Staphylococcus saprophyticus followed by Staphylococcus succinus and Staphylococcus equorum belonging to the Staphylococcus genus. Real-time PCR DNA melting curve analysis and high-resolution melting (HRM) analysis targeting the V1 + V3 regions of 16S rDNA were also applied for the discrimination of isolates belonging to different species. It was observed statistically different Tm values and species-specific HRM profiles for all except 2 species (S. saprophyticus and Staphylococcus xylosus) that have high 16S rDNA sequence similarity. The combination of rep-PCR and/or PCR-RAPD with 16S rRNA gene sequencing was an efficient approach for the characterization and identification of the GCC population in spontaneously fermented sucuk. On the other hand, intercalating dye assays were found to be a simple and very promising technique for the differentiation of the GCC population at species level. PMID:24410408

  4. Amino acid conversions by coagulase-negative staphylococci in a rich medium: Assessment of inter- and intraspecies heterogeneity.

    Science.gov (United States)

    Stavropoulou, Despoina Angeliki; Borremans, Wim; De Vuyst, Luc; De Smet, Stefaan; Leroy, Frédéric

    2015-11-01

    The ability of coagulase-negative staphylococci (CNS) to convert amino acids into volatile compounds and biogenic amines was investigated after 24h and 48 h of incubation in a rich medium (brain heart infusion). Volatile compounds were measured with static-headspace gas chromatography and mass spectrometry (SH-GC-MS); biogenic amine measurements were carried out with a newly developed method based on ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). In total, 56 CNS strains from five different species were used, namely Staphylococcus carnosus, Staphylococcus epidermidis, Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus xylosus. With respect to the production of volatile compounds, the leucine-derived 3-methyl butanol was produced over time by most CNS strains, up to 52 μM for S. xylosus W1-1 after 48 h of incubation. The average production by strains of S. xylosus was significantly higher than for strains of S. carnosus, whereas strains of S. epidermidis turned out to be poor producers. Yet, differences between species were blurred to a large degree because of the high strain variability. A few strains also produced 3-methyl butanal on top of the amount that was already present in the medium background, although most CNS led to a decrease of this compound. Concerning biogenic amines, the average total concentrations per species remained below 100 μM after 48 h of incubation. The most abundant variant was 2-phenylethylamine (PEA), especially within S. carnosus (average of 65 μM after 48 h of incubation). Yet, some individual strains were able to produce higher concentrations, as found for the PEA production of 295 μM by S. epidermidis ATCC 12228 after 48 h of incubation. The insights obtained during this study indicate heterogeneity and are of importance in view of both starter culture development and the evaluation of a spontaneously established CNS microbiota in artisan-type meat fermentations

  5. Process-driven bacterial community dynamics are key to cured meat colour formation by coagulase-negative staphylococci via nitrate reductase or nitric oxide synthase activities.

    Science.gov (United States)

    Sánchez Mainar, María; Leroy, Frédéric

    2015-11-01

    The cured colour of European raw fermented meats is usually achieved by nitrate-into-nitrite reduction by coagulase-negative staphylococci (CNS), subsequently generating nitric oxide to form the relatively stable nitrosomyoglobin pigment. The present study aimed at comparing this classical curing procedure, based on nitrate reductase activity, with a potential alternative colour formation mechanism, based on nitric oxide synthase (NOS) activity, under different acidification profiles. To this end, meat models with and without added nitrate were fermented with cultures of an acidifying strain (Lactobacillus sakei CTC 494) and either a nitrate-reducing Staphylococcus carnosus strain or a rare NOS-positive CNS strain (Staphylococcus haemolyticus G110), or by relying on the background microbiota. Satisfactory colour was obtained in the models prepared with added nitrate and S. carnosus. In the presence of nitrate but absence of added CNS, however, cured colour was only obtained when L. sakei CTC 494 was also omitted. This was ascribed to the pH dependency of the emerging CNS background microbiota, selecting for nitrate-reducing Staphylococcus equorum strains at mild acidification conditions but for Staphylococcus saprophyticus strains with poor colour formation capability when the pH decrease was more rapid. This reliance of colour formation on the composition of the background microbiota was further explored by a side experiment, demonstrating the heterogeneity in nitrate reduction of a set of 88 CNS strains from different species. Finally, in all batches prepared with S. haemolyticus G110, colour generation failed as the strain was systematically outcompeted by the background microbiota, even when imposing milder acidification profiles. Thus, when aiming at colour formation through CNS metabolism, technological processing can severely interfere with the composition and functionality of the meat-associated CNS communities, for both nitrate reductase and NOS activities

  6. Halophilic bacteria are colonizing the exhibition areas of the Capuchin Catacombs in Palermo, Italy.

    Science.gov (United States)

    Piñar, G; Kraková, L; Pangallo, D; Piombino-Mascali, D; Maixner, F; Zink, A; Sterflinger, K

    2014-07-01

    The Capuchin Catacombs of Palermo, Italy, contain over 1800 mummies dating from the 16th to 20th centuries AD. Their environment is not conducive to the conservation of the remains due to, among other factors, water infiltration, which is producing salt efflorescences on the walls. A multiphasic approach was applied to investigate the halophilic microbiota present in the Catacombs. Enrichment cultures were conducted on media containing different NaCl concentrations, ranging from 3 to 20 %. For screening of the strains, the following two PCR-based methods were used and compared: fluorescence internal transcribed spacer PCR (f-ITS) and random amplification of polymorphic DNA (RAPD) analyses. Results derived from RAPD profiles were shown to be slightly more discriminative than those derived from f-ITS. In addition, the proteolytic and cellulolytic abilities were screened through the use of plate assays, gelatin agar and Ostazin Brilliant Red H-3B (OBR-HEC), respectively. Many of the strains isolated from the wall samples displayed proteolytic activities, such as all strains belonging to the genera Bacillus, Virgibacillus and Arthrobacter, as well as some strains related to the genera Oceanobacillus, Halobacillus and Idiomarina. In addition, many of the strains isolated from materials employed to stuff the mummies showed cellulolytic activities, such as those related to species of the genera Chromohalobacter and Nesterenkonia, as well as those identified as Staphylococcus equorum and Halomonas sp. Furthermore, many of the strains were pigmented ranging from yellow to a strong pink color, being directly related to the discoloration displayed by the materials. PMID:24863363

  7. Why is it important to correctly identify Haemonchus species? Por que é importante a identificação correta das espécies de Haemonchus?

    Directory of Open Access Journals (Sweden)

    Alessandro Francisco Talamini do Amarante

    2011-12-01

    Full Text Available Parasitic gastroenteritis caused by Haemonchus spp. is a major cause of economic losses in the livestock industry because it impairs weight gain and increases mortality in cattle and small ruminants, especially in tropical and subtropical areas. The proper identification of the various species, as well as knowledge regarding the epidemiology of parasitic gastroenteritis, is essential for the establishment of sustainable strategies of parasite control. This review focuses on the use of easily applied, low-cost parasitological methods of identifying Haemonchus species on the basis of their morphology. In most studies carried out in Brazil, the distinctions between Haemonchus contortus and Haemonchus placei have not been considered. Many reports of H. contortus, particularly in cattle, might actually represent H. placei. The appropriate identification of species is therefore indispensable. In addition to the measurement of male spicules, new morphological characteristics, such as the synlophe, should be evaluated in order to differentiate between and among species. Measurements of infective larvae in fecal cultures can also indicate the identity of Haemonchus species. This approach can be quite useful in studies that do not involve animal sacrifice, such as studies of anthelmintic resistance based on the fecal egg count reduction test.Infecções por Haemonchus spp. são uma das principais causas de perda econômica nas criações de ruminantes devido à redução no ganho de peso e mortalidade de bovinos e pequenos ruminantes, especialmente em regiões com clima tropical e subtropical. A identificação precisa das diferentes espécies, bem como o conhecimento sobre a epidemiologia das gastroenterites parasitárias, são fundamentais para a elaboração de estratégias sustentáveis de profilaxia das parasitoses. Essa revisão tem por objetivo central, abordar os principais métodos parasitológicos utilizados na identificação morfológica das

  8. [Recent findings on the genetics of gastro-intestinal nematode resistance in ruminants].

    Science.gov (United States)

    Carta, A; Scala, A

    2004-06-01

    The control of helminthiases in ruminants raised in open pasture has been mainly undertaken by using prophylactic measures in the environment, but these are often inadequate due to incorrect application. With the appearance of anthelmintics, the strategy for controlling these parasitoses, passed to pharmacological treatments which became effective in reducing their impact. However, the frequent and incorrect utilisation of these molecules resulted in resistance to anthelmintics and the presence of chemical residues in animal products for human consumption. Anthelmintic resistance is widespread throughout the world, heterogeneous and probably underestimated. This has encouraged the introduction of homeopathic agents and products derived from plants whose effectiveness has not been scientifically assessed. It is well known that it is possible to detect differences in resistance to the most important parasites between breeds. In Europe, it has been reported that some ovine autochthonous breeds, Scottish Blackface and Lacaune, showed higher resistance. The implementation of breeding strategies aimed at obtaining animals with naturally low susceptibility to nematode infestations could therefore play an increasingly important role. Standard animal breeding techniques have been largely successful in improving the performance of domestic animals in the last century. Standard quantitative selection requires field data on: i) individual phenotype performance; ii) expected covariance among animals due to blood relationship between them. The whole process of predicting the breeding value of animals in order to select subsequently the genetically superior parents of the next generation is entirely based on sophisticated computations (BLUP-animal model). In sheep, the main objective is always selecting for milk yield and sometimes, in addition, milk composition. However, due to the evolution of the EU agricultural policy and consumer demand in terms of healthy and organic food

  9. Ecology of the free-living stages of major trichostrongylid parasites of sheep.

    Science.gov (United States)

    O'Connor, Lauren J; Walkden-Brown, Stephen W; Kahn, Lewis P

    2006-11-30

    Significant developments over recent decades make it timely to review the ecology of the major gastrointestinal nematode (GIN) species of sheep. These include the relentless development and spread of anthelmintic resistance in all of the major sheep production regions of the world, and the consequent drive towards integrated parasite management (IPM) systems incorporating non-chemotherapeutic strategies such as grazing management. The success of such programs is dependent on a detailed understanding of the environmental influences on the free-living stages of the nematode lifecycle. Major reviews of the subject were conducted prior to 1980, however considerable work has been completed since, including the development of mathematical models describing the epidemiology of GIN infection. Knowledge of the temperature thresholds for free-living development has also improved, while investigations of moisture influences and interactions with temperature have allowed more effective exploitation of environmental effects for IPM. This review re-evaluates our understanding of the factors that determine the success or failure of the free-living phases of the lifecycle in light of these developments. Temperature and moisture are the dominant influences on the free-living stages of Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus colubriformis, with the effects of pasture conditions playing a significant modulating role. Early in the free-living phase, the developmental success of the three GIN species is limited by susceptibility to cold temperatures. In general, H. contortus is most susceptible, followed by T. colubriformis and then T. circumcincta. The length of the development cycle is dependent largely on temperature, with development rate increasing at warmer temperatures. However, in order for development to proceed to the infective larval stage, addition of moisture is generally required. There has been considerably less work quantifying the effects

  10. Niveles de infestación parasitaria y condición corporal en bovinos doble propósito infestados en condiciones naturales (Degree of infestation and body condition in dual purpose naturally infected cattle

    Directory of Open Access Journals (Sweden)

    Gustavo Morales

    2006-04-01

    work was carried out in a dual purpose farm oriented to milk production, located in San Antonio, Municipality of Pedraza in Barinas State. 65 cattle were coprologically examined by mean of McMaster technique with a oversaturated solution of NaCl as flotation liquid. The body condition of the animals was evaluated by mean the method of the scale with scores from 1 to 5 and 2,5 as inflection point. The packed cell volume was evaluated by mean of the microhaematocrit microcentrifugation method. The conjuntive color of each animal was evaluated as well. The highest e.p.g. count were observed in animals with a body condition ≤ 2,5. This animals can be considered as wormy animals, a small fraction of the herd showed a good body condition (≥ 3 and high e.p.g. count. This animals can be considered as resilient. Both group of animals are strong grass contaminants. The haematocrit values were similar between no wormy animals and resilient and higher than wormy animals. No association was found between haematocrit and conjuntive color. No anthelmintic resistance was diagnosed against the drugs used in the farm (Doramectine, Ivermectine and Albendazole.

  11. [Recent findings on the genetics of gastro-intestinal nematode resistance in ruminants].

    Science.gov (United States)

    Carta, A; Scala, A

    2004-06-01

    The control of helminthiases in ruminants raised in open pasture has been mainly undertaken by using prophylactic measures in the environment, but these are often inadequate due to incorrect application. With the appearance of anthelmintics, the strategy for controlling these parasitoses, passed to pharmacological treatments which became effective in reducing their impact. However, the frequent and incorrect utilisation of these molecules resulted in resistance to anthelmintics and the presence of chemical residues in animal products for human consumption. Anthelmintic resistance is widespread throughout the world, heterogeneous and probably underestimated. This has encouraged the introduction of homeopathic agents and products derived from plants whose effectiveness has not been scientifically assessed. It is well known that it is possible to detect differences in resistance to the most important parasites between breeds. In Europe, it has been reported that some ovine autochthonous breeds, Scottish Blackface and Lacaune, showed higher resistance. The implementation of breeding strategies aimed at obtaining animals with naturally low susceptibility to nematode infestations could therefore play an increasingly important role. Standard animal breeding techniques have been largely successful in improving the performance of domestic animals in the last century. Standard quantitative selection requires field data on: i) individual phenotype performance; ii) expected covariance among animals due to blood relationship between them. The whole process of predicting the breeding value of animals in order to select subsequently the genetically superior parents of the next generation is entirely based on sophisticated computations (BLUP-animal model). In sheep, the main objective is always selecting for milk yield and sometimes, in addition, milk composition. However, due to the evolution of the EU agricultural policy and consumer demand in terms of healthy and organic food

  12. Evolution and Biogeography of Haemonchus contortus: Linking Faunal Dynamics in Space and Time.

    Science.gov (United States)

    Hoberg, E P; Zarlenga, D S

    2016-01-01

    developmental thresholds defined by temperature and humidity for larval stages) will be substantial determinants in the potential outcomes for widespread geographical and host colonization which are predicted to unfold over the coming century. Insights about deeper evolutionary events, ecology and biogeography are critical as understanding history informs us about the possible range of responses in complex systems under new regimes of environmental forcing, especially, in this case, ecological perturbation linked to climate change. A deeper history of perturbation is relevant in understanding contemporary systems that are now strongly structured by events of invasion and colonization. The relaxation of abiotic and biotic controls on the occurrence of H. contortus, coincidental with inception and dissemination of anthelmintic resistance may be synergistic, serving to exacerbate challenges to control parasites or to limit the socioeconomic impacts of infection that can influence food security and availability. Studies of haemonchine nematodes contribute directly to an expanding model about the nature of diversity and the evolutionary trajectories for faunal assembly among complex host-parasite systems across considerable spatial and temporal scales.

  13. Evolution and Biogeography of Haemonchus contortus: Linking Faunal Dynamics in Space and Time.

    Science.gov (United States)

    Hoberg, E P; Zarlenga, D S

    2016-01-01

    developmental thresholds defined by temperature and humidity for larval stages) will be substantial determinants in the potential outcomes for widespread geographical and host colonization which are predicted to unfold over the coming century. Insights about deeper evolutionary events, ecology and biogeography are critical as understanding history informs us about the possible range of responses in complex systems under new regimes of environmental forcing, especially, in this case, ecological perturbation linked to climate change. A deeper history of perturbation is relevant in understanding contemporary systems that are now strongly structured by events of invasion and colonization. The relaxation of abiotic and biotic controls on the occurrence of H. contortus, coincidental with inception and dissemination of anthelmintic resistance may be synergistic, serving to exacerbate challenges to control parasites or to limit the socioeconomic impacts of infection that can influence food security and availability. Studies of haemonchine nematodes contribute directly to an expanding model about the nature of diversity and the evolutionary trajectories for faunal assembly among complex host-parasite systems across considerable spatial and temporal scales. PMID:27238001

  14. 柑橘黄龙病寄主长春花内生细菌的分离及功能鉴定%Isolation, identification and basic function analysis of plant associated bacteria from huanglongbing's host plant-Catharanthus roseus

    Institute of Scientific and Technical Information of China (English)

    李佳; 殷幼平; 郑莉萍; 孙梦黎; 向晟; 郑月慧; 王中康

    2014-01-01

    [目的]感柑橘黄龙病长春花植株与健康长春花植株不同部位内生细菌菌群结构及功能对柑橘黄龙病菌与长春花内生细菌的相关性研究提供理论基础.[方法]利用兼性厌氧可培养技术以及植物内生菌功能特性分析相结合的方法.[结果]分别从感病和健康长春花叶、茎、根的组织中分离获得67株内生细菌,与GenBank中29种细菌的相似性达到97%-100%.其中短小杆菌属(Curtobacterium sp.)、欧文氏菌属(Erwinia sp.)、蜡样芽胞杆菌(Bacillus cereus)为感病长春花内生细菌的优势菌群,鞘胺醇单胞菌属(Brevundimonas sp.)、芽胞杆菌属(Bacillussp.)为健康长春花内生细菌的优势菌群;马胃葡萄球菌(Staphylococcus equorum)为两者的共同优势菌群.29种内生细菌进行功能分析,其中6株内生细菌至少具有4种功能特性,分属于马胃葡萄球菌、苏云金芽孢杆菌、巨大芽孢杆菌、短小杆菌属、摩氏摩根菌(Morganella morganii)及溶杆菌属(Lysobacter sp.)5个属.[结论]感病与健康长春花植株中均含有丰富的内生细菌且差异较大,黄龙病菌的存在改变了长春花原有内生细菌的菌群结构.通过分析菌群的差异,有望找到与柑橘黄龙病菌生长相关的菌种.

  15. Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398.

    Science.gov (United States)

    Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

    2016-05-01

    The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1-5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

  16. Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398.

    Science.gov (United States)

    Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

    2016-05-01

    The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1-5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

  17. Population dynamics of two antilisterial cheese surface consortia revealed by temporal temperature gradient gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Hasler Madlen

    2010-03-01

    Full Text Available Abstract Background Surface contamination of smear cheese by Listeria spp. is of major concern for the industry. Complex smear ecosystems have been shown to harbor antilisterial potential but the microorganisms and mechanisms involved in the inhibition mostly remain unclear, and are likely related to complex interactions than to production of single antimicrobial compounds. Bacterial biodiversity and population dynamics of complex smear ecosystems exhibiting antilisterial properties in situ were investigated by Temporal temperature gradient gel electrophoresis (TTGE, a culture independent technique, for two microbial consortia isolated from commercial Raclette type cheeses inoculated with defined commercial ripening cultures (F or produced with an old-young smearing process (M. Results TTGE revealed nine bacterial species common to both F and M consortia, but consortium F exhibited a higher diversity than consortium M, with thirteen and ten species, respectively. Population dynamics were studied after application of the consortia on fresh-produced Raclette cheeses. TTGE analyses revealed a similar sequential development of the nine species common to both consortia. Beside common cheese surface bacteria (Staphylococcus equorum, Corynebacterium spp., Brevibacterium linens, Microbacterium gubbeenense, Agrococcus casei, the two consortia contained marine lactic acid bacteria (Alkalibacterium kapii, Marinilactibacillus psychrotolerans that developed early in ripening (day 14 to 20, shortly after the growth of staphylococci (day 7. A decrease of Listeria counts was observed on cheese surface inoculated at day 7 with 0.1-1 × 102 CFU cm-2, when cheeses were smeared with consortium F or M. Listeria counts went below the detection limit of the method between day 14 and 28 and no subsequent regrowth was detected over 60 to 80 ripening days. In contrast, Listeria grew to high counts (105 CFU cm-2 on cheeses smeared with a defined surface culture

  18. Species identification, slime production and oxacillin susceptibility in coagulase-negative staphylococci isolated from nosocomial specimens Identificação de espécies, produção de "slime" e sensibilidade a oxacilina em amostras de Staphylococcus coagulase-negativo isoladas de espécimes nosocomiais

    Directory of Open Access Journals (Sweden)

    Lucía E. Alcaráz

    2003-04-01

    Full Text Available Ninety-two coagulase negative staphylococci (CNS (forty-five of clinical origin and forty-seven of environmental origin, collected in a hospital in San Luis, Argentina, from March to June, 1999, were identified to species level by the ID 32 Staph and API Staph System (bioMérieux. Slime production was investigated by the quantitative and qualitative methods. Oxacillin susceptibility was determined by the disk diffusion test (1 µg, the agar dilution method (0.125 to 4 mg/ml and agar screen (6 µg/ml. The presence of mecA gene was investigated by PCR. The clinical CNS species most commonly isolated were S. epidermidis, S. haemolyticus, S. hominis and S. saprophyticus. The frequency of slime production by clinical and environmental isolates was similar (25/45 and 27/47, respectively and the results obtained by the quantitative and the qualitative methods correlated well. The mecA gene was detected in all S. epidermidis, S. haemolyticus and S. hominis isolates, which were resistant to oxacillin by the phenotypic methods. However, this gene was not present in S. klossii, S. equorum, S. xylosus and S. capitis strains. The gene was neither found in two out of the six S. saprophyticus isolates, in two out of three S. cohnii subsp. urealyticum isolates and in two out of five S. cohnii subsp. cohnii isolates, all of which resulted oxacillin resistant according to MIC. The gene was not found in oxacillin-susceptible strains either. Most of the CNS isolates (enviromental and clinical that were slime producers were found to be oxacillin resistant, which makes the early detection of these microorganisms necessary to prevent their dissemination in hospitals, particularly among immunocompromised patients.Noventa e duas amostras de Staphylococcus coagulase negativo (SCN, (45 amostras clínicas e 47 ambientais, coletadas em um hospital de San Luis, Argentina, durante o período de março a junho de 1999, foram identificadas até espécies, empregando-se os

  19. Evaluation of resistance in a selected field strain of Haemonchus contortus to ivermectin and moxidectin using the Larval Migration on Agar Test Avaliação da resistência em um isolado de campo selecionado de Haemonchus contortus à ivermectina e moxidectina usando o Teste de Migração de Larvas em Ágar

    Directory of Open Access Journals (Sweden)

    Fernanda S. Fortes

    2013-02-01

    Full Text Available Haemonchus contortus is one of the most common and economically significant causes of disease in small ruminants worldwide, and the control programs of parasitic nematodes - including H. contortus - rely mostly on the use of anthelmintic drugs. The consequence of the use of this, as the sole sanitary strategy to avoid parasite infections, was the reduction of the efficacy of all chemotherapeutic products with a heavy selection for resistance. The widespread of anthelmintic resistance and the difficulty of its early diagnosis has been a major concern for the sustainable parasite management on farms. The objective of this research was to determine and compare the ivermectin (IVM and moxidectin (MOX effect in a selected field strain of H. contortus with a known resistance status, using the in vitro larval migration on agar test (LMAT. Third stage larvae of the selected isolate were obtained from faecal cultures of experimentally infected sheep and incubated in eleven increasing diluted concentrations of IVM and MOX (6, 12, 24, 48, 96, 192, 384, 768, 1536, 3072 and 6144µg/mL. The dose-response sigmoidal curves were obtained using the R² value of >0.90 and the lethal concentration (LC50 dose for the tested anthelmintic drugs using a four-parameter logistic model. The LC50 value for MOX was significantly lower than IVM (1.253µg/mL and 91.06µg/mL, identifying the H. contortus isolate as considerably less susceptible to IVM compared to MOX. Furthermore, the LMAT showed a high consistency (pHaemonchus contortus é uma das causas mais comuns e economicamente significativas de doença em produções de pequenos ruminantes em todo o mundo, e os programas de controle de parasitas nematoides - incluindo H. contortus - baseiam-se principalmente no uso de drogas anti-helmínticas. A consequência da utilização desses compostos, como sendo a única estratégia sanitária para evitar infecções por parasitas, tem sido a redução da eficácia de todos os