Assessing the Efficacy of Albendazole against Fasciola hepatica in Naturally Infected Cattle by In Vivo and In Vitro Methods

This study was performed on a cattle farm with a long-term use of albendazole (ABZ) and a permanent history of fasciolosis for comparing in vivo and in vitro methods for the detection of anthelmintic resistance and drug efficacy. A selected group of 10 Charolais cows was treated in autumn 2020 with ABZ at a dose of 7.5 mg/kg body weight. Another group of 10 cows remained untreated as a control. The faecal egg count reduction test was used to determine in vivo efficacy. The percentage reduction of eggs on day 14 after treatment ranged from 77 to 81.8%, depending on the formula used for calculation. The in vitro egg hatch test (EHT) was used as a second diagnostic method. F. hepatica eggs for the EHT were isolated from faecal samples. The test was performed in two versions differing in the length of incubation with ABZ (12 h and 15 d). The percentage of eggs with inhibited development at a concentration of 0.5 μM in both versions of the EHT agreed with the in vivo results. Ovicidal activity at a concentration of 0.5 μM in the 12-h version suggested a reduced efficacy of ABZ (65.40%). An EHT prepared using pooled faecal samples was a prospective method for the detection of efficacy and ABZ resistance in F. hepatica.

Download Full-text

Worm-control practices and prevalence of anthelmintic resistance using in vivo FECRTs on smallholder sheep farms in Lithuania

Helminthologia ◽

10.1515/helmin-2015-0064 ◽

2016 ◽

Vol 53 (1) ◽

pp. 24-30 ◽

Cited By ~ 4

Author(s):

T. Kupčinskas ◽

I. Stadalienė ◽

A. Šalomskas ◽

P. Trusevičius ◽

M. Varady ◽

...

Keyword(s):

Anthelmintic Resistance ◽

Gastrointestinal Nematodes ◽

Parasitic Nematodes ◽

Future Studies ◽

Faecal Samples ◽

Two Samples ◽

Faecal Egg Count ◽

Worm Control

SummaryThis study determined the prevalence of anthelmintic resistance (AR) in parasitic nematodes on smallholder sheep farms in Lithuania from April to November 2014. Faecal samples were collected from two groups of 10-15 sheep treated with fenbendazole (FBZ) or ivermectin (IVM) on 18 sheep farms. Two samples were collected from each group: on day zero (T1) and 10-14 days after treatment. Faecal egg counts (eggs per gramme, EPG) were determined using a modified McMaster technique. Animals with < 140 EPG on day zero were removed from the analysis. The prevalence of AR was estimated using the in vivo faecal egg count reduction test. AR to FBZ was detected on three of 15 farms where FBZ was used (20 %) and was suspected on one farm (6.7 %). AR to IVM was detected on two of 16 farms where IVM was used (12.5 %). The main species of resistant gastrointestinal nematodes (GINs) identified after treatment were Teladorsagia spp. and Trichostrongylus spp. A questionnaire surveying 71 sheep farmers estimated that 71.8 % of sheep farmers used anthelmintics against GINs. IVM was the most frequently (68.6 %) applied anthelmintic, and 62.7 % of the respondents reported treating their animals twice a year. This study confirmed the presence of AR to GIN infections on sheep farms in Lithuania. Future studies should assess the prevalence of AR to GIN infection using in vitro methods.

Download Full-text

Comparison of two in vitro methods for the detection of ivermectin resistance in Haemonchus contortus in sheep

Helminthologia ◽

10.1515/helmin-2015-0002 ◽

2016 ◽

Vol 53 (2) ◽

pp. 120-125 ◽

Cited By ~ 2

Author(s):

M. Urda Dolinská ◽

A. Königová ◽

M. Babják ◽

M. Várady

Keyword(s):

Drug Resistance ◽

Haemonchus Contortus ◽

Anthelmintic Resistance ◽

Economic Losses ◽

Parasitic Nematodes ◽

Migration Inhibition ◽

In Vitro Methods ◽

Parasitic Helminths

SummaryGastrointestinal parasitic nematodes in sheep cause severe economic losses. Anthelmintics are the most commonly used drugs for prophylaxis and therapy against parasitic helminths. The problem of drug resistance has developed for all commercially available anthelmintics in several genera and classes of helminths. In vitro and in vivo tests are used to detect anthelmintic resistance. Two in vitro methods (larval migration inhibition test and micromotility test) for the detection of ivermectin (IVM) resistance were compared using IVM-resistant and IVM-susceptible isolates of Haemonchus contortus. The degree of resistance for each test was expressed as a resistance factor (RF). The micromotility test was more sensitive for quantitatively measuring the degree of resistance between susceptible and resistant isolates. The RFs for this test for IVM and eprinomectin ranged from 1.00 to 108.05 and from 3.87 to 32.32, respectively.

Download Full-text

Multiple anthelmintic resistance at a goat farm in Slovakia

Helminthologia ◽

10.2478/helm-2021-0014 ◽

2021 ◽

Vol 58 (2) ◽

pp. 173-178

Author(s):

M. Babják ◽

A. Königová ◽

M. Várady

Keyword(s):

Inhibitory Concentration ◽

Anthelmintic Resistance ◽

Small Ruminants ◽

Threshold Concentration ◽

Faecal Egg Count ◽

Goat Farm ◽

Threshold Criteria ◽

Larval Development Test

Summary Cases of parasite resistance to the main classes of anthelmintics are increasingly reported from small ruminants at farms in Europe. We visited a goat farm in Slovakia in November 2019 with suspected parasite problems that reduced productivity and performed an in vivo faecal egg count reduction test (FECRT) and an in vitro larval development test (LDT) for all three main classes of anthelmintics. The lowest efficacy (60 %) detected by FECRT was for ivermectin (IVM). Benzimidazole (BZ) efficacy ranged between 80.3 and 86.5 %, and levamisole (LEV) efficacy was 94 %. The results from the in vivo FECRT test were confirmed by the in vitro LDT. Minimum inhibitory concentration (MIC) 173.6 ng/ml for IVM several times exceeded the recommended threshold of 21.6 ng/ml. Mean LD50 for BZ was equal to the threshold concentration, but the other threshold criteria indicated a low level of resistance in the population. The LDT did not indicate the presence of resistance only for LEV. The MIC 1.0 μg/ml for LEV was evaluated as susceptible with respect to species composition. Teladorsagia was the dominant genus after treatment with BZ, IVM, and LEV. Haemonchus contortus was identifi ed after treatment with BZ and LEV.

Download Full-text

Avermectins and milbemycins against Fasciola hepatica: In vivo drug efficacy and in Vitro receptor binding

International Journal for Parasitology ◽

10.1016/0020-7519(95)00026-x ◽

1995 ◽

Vol 25 (8) ◽

pp. 923-927 ◽

Cited By ~ 14

Author(s):

W.L. Shoop ◽

D.A. Ostlind ◽

S.P. Rohrer ◽

G. Mickle ◽

H.W. Haines ◽

...

Keyword(s):

Receptor Binding ◽

Fasciola Hepatica ◽

Drug Efficacy

Download Full-text

Anthelmintic resistance of horse strongyle nematodes to ivermectin and pyrantel in Lithuania

Acta Veterinaria Scandinavica ◽

10.1186/s13028-021-00569-z ◽

2021 ◽

Vol 63 (1) ◽

Author(s):

Evelina Dauparaitė ◽

Tomas Kupčinskas ◽

Georg von Samson-Himmelstjerna ◽

Saulius Petkevičius

Keyword(s):

Anthelmintic Resistance ◽

Test Group ◽

Horse Population ◽

Treatment Practices ◽

Faecal Samples ◽

Faecal Egg Count ◽

Horse Farms ◽

Available Information ◽

And Control

Abstract Background With intensive use of anthelmintic drugs in recent decades, anthelmintic resistance (AR) in horse nematodes is becoming a growing issue in many countries. However, there is little available information about the parasites, treatment practices or AR in the horse population in Lithuania. The aim of this study was to assess the current situation of AR on horse farms in Lithuania. The study was conducted in 25 stables on horses with a strongyle faecal egg count (FEC) of ≥ 200 eggs per gram. A faecal egg count reduction test (FECRT) was performed on each farm after administration of ivermectin (IVM) or pyrantel (PYR). Results The efficacy of IVM was comparatively high, with 98.8% of 250 horses having a zero egg count 14 days after treatment. Two conditions were used to interpret the FECRT results for PYR: firstly, resistance was determined when FECR was < 90% and the lower 95% confidence interval (LCL) was < 80%, and secondly when in addition the upper confidence level (UCL) was < 95%. Under the first condition, resistance against PYR was found in five stables (25% of all tested herds), while when considering the UCL as well, resistance was only detected in two stables (8%). The FEC showed a significant (P < 0.01) difference between the treatment and control groups. Only cyathostomin larvae were detected in larval cultures derived from strongyle-positive faecal samples collected 14 days after treatment of a test group with PYR. Conclusions This in vivo study showed that PYR resistance is prevalent on horse farms in Lithuania, while the efficacy of IVM still appears to be unaffected. However, further studies of ivermectin resistance are needed. These findings should guide the implementation of more sustainable management of strongyle infections in horses in Lithuania.

Download Full-text

First report of multiple drug-resistant gastrointestinal nematodes of sheep in Arbat District, Sulaymaniyah, Iraq detected by in vivo and in vitro methods

Journal of Veterinary Research ◽

10.2478/jvetres-2021-0047 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Hiewa Othman Dyary ◽

Hamasalih Qadir Banaz

Keyword(s):

Anthelmintic Resistance ◽

Small Ruminants ◽

Gastrointestinal Nematodes ◽

Multiple Drug ◽

Northern Iraq ◽

Multiple Drug Resistant ◽

Faecal Egg Count ◽

The Mean

Abstract Introduction The control of gastrointestinal nematodes (GINs) in small ruminants is principally dependent on anthelmintic therapy, which encounters the rising problem of anthelmintic resistance (AR) development. Veterinarians reported anthelmintic failure in several sheep farms in Arbat District, Sulaymaniyah, northern Iraq, which called for a systematic study about the efficacy of three commonly used drugs: albendazole, ivermectin, and levamisole. Material and Methods A faecal egg count reduction test (FECRT) was conducted to elucidate the anthelmintics’ efficacies, with coprocultures to determine the GINs parasitising sheep in the study area. Larval development assays (LDAs) were conducted to determine the drugs’ median inhibitory concentrations (IC50). Results The FECRT revealed that AR was widespread to all three drugs, and ivermectin was the least effective, reducing the faecal egg counts (FECs) by 50.5% to 57.1%. The coprocultures revealed that the GIN genera of sheep in Arbat District were Trichostrongylus, Nematodirus, and Trichuris, and the resistance was mainly due to Trichostrongylus species. The mean IC50 of albendazole, ivermectin, and levamisole were 0.073 ng/mL, 7.97 ng/mL, and 1.43 ng/mL, respectively. Conclusion This study is the first Iraqi report of AR confirmed by both in vivo FECRT and in vitro LDA methods.

Download Full-text

First Report of Anthelmintic Resistance in Gastrointestinal Nematodes in Goats in Romania

Animals ◽

10.3390/ani11102761 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2761

Author(s):

Adrian Valentin Potârniche ◽

Marcin Mickiewicz ◽

Diana Olah ◽

Constantin Cerbu ◽

Marina Spînu ◽

...

Keyword(s):

Anthelmintic Resistance ◽

Small Ruminants ◽

Nematode Species ◽

Gastrointestinal Nematodes ◽

Diagnostic Methods ◽

Dairy Goat ◽

Control Group ◽

In Vitro Methods

Currently, there are three classes of anthelmintics most commonly used in small ruminants: the benzimidazoles (BZs), macrocyclic lactones (MLs) and cholinergic agonists (especially levamisole; LEV). The widespread use of those products has led to the emergence of drug-resistant parasite strains which represents a serious threat to the livestock industry. In the present study, we describe for the first time a case of resistance to anthelmintics in goats in Romania. The study was carried out in 2021 in a dairy goat herd from the Transylvania region. Two types of diagnostic methods were used to confirm anthelmintic resistance (AR). First, the faecal egg count reduction test (FECRT), an in vivo AR diagnostic method, was used to evaluate the efficacy of eprinomectin (EPM). The results of this test were analysed applying two different calculative methods that are used only in treated animals (without the control group). Furthermore, two in vitro methods were used: the egg hatch test (EHT) for the detection of resistance to BZs, and the larval development test (LDT) for detection of resistance to all three classes of anthelmintics. The results of FECRT indicate the resistance of gastrointestinal nematodes (GINs) to EPM in both calculative methods (FECR1 = −88% and FECR2 = −202%). In addition, the results obtained for ivermectin aglycone (IVM-AG) in LDT also indicate resistance to drugs from MLs group, especially avermectins. Similarly, the results of in vitro methods (EHT and LDT) indicate resistance to BZs in this herd. LEV was the only drug that stopped the development of L3 larvae 100% (LDT). H. contortus was the only nematode species found in coproculture after EPM treatment. Furthermore, H. contotus L3 larvae was the only species found in the wells with the highest concentrations of thiabendazole (TBZ) and IVM-AG in LDT. This suggests that resistance to both BZs and MLs was present for that species.

Download Full-text

Analysis of antidepressant properties of some Papaver species by in vivo and in vitro methods

Planta Medica ◽

10.1055/s-0035-1565761 ◽

2015 ◽

Vol 81 (16) ◽

Cited By ~ 2

Author(s):

OML Bayazeid ◽

F Yalcin ◽

M İlhan ◽

H Karahan ◽

E Kupeli-Akkol ◽

...

Keyword(s):

In Vitro Methods

Download Full-text

The Effects of Some Synthetic Compounds on In Vitro Fibrinolytic Activity Measured by Different Methods and the Relevance to Activity In Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649018 ◽

1972 ◽

Vol 28 (03) ◽

pp. 351-358

Author(s):

A.J Baillie ◽

A. K Sim

Keyword(s):

Inhibitory Activity ◽

Substrate Concentration ◽

Fibrinolytic Activity ◽

Synthetic Compounds ◽

In Vitro Methods ◽

Narrow Concentration Range

SummaryThe activity of several synthetic compounds, rated from good to poor (or inactive) fibrinolytic activators, has been assessed by two different commonly-used in vitro methods. Compounds shown to be active over a narrow concentration range in the hanging clot test were shown to be inhibitors of plasmin and trypsin in the casein-olytic test. The inhibitory activity of these compounds was shown to increase with increasing substrate concentration and apparent activity in the hanging clot test. Possible explanations and relevance of these observations are discussed.

Download Full-text

In Vitro Toxicology Methods in Risk Assessment

Alternatives to Laboratory Animals ◽

10.1177/026119299602400305 ◽

1996 ◽

Vol 24 (3) ◽

pp. 325-331

Author(s):

Iain F. H. Purchase

Keyword(s):

Risk Assessment ◽

Hazard Assessment ◽

Human Health Risk ◽

In Vitro Test ◽

In Vitro Methods ◽

New Concepts ◽

Vitro Test

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.

Download Full-text