Sustainable approach to control gastrointestinal nematodes using pelargonium quercetorum Agnew in goats.

The use of medicinal plants as a means of combating parasites is becoming increasingly popular due to general resistance to synthetic anthelmintics. Goats typically respond less well to anthelminthic treatments, which may increase their resistance to nematodes. For this purpose, the anthelmintic effect of Pelargonium quercetorum Agnew (P. quercetorum) extract was tested in an in vivo study against gastrointestinal parasites of goats. A total of 40 goats naturally infected with mixed gastrointestinal nematode species were divided into four groups: the first group was treated with albendazole (7.5 mg/kg), the second group received a single dose of closantel (7.5 mg/kg), the third group received plant extract (7.5 mg/kg), and the fourth group served as an untreated control. Fecal egg counts (FEC) were carried out on day 14, as well as day 0, which was prior to the first treatment dose. According to the results, maximum reduction in FEC percentage was observed in P. quercetorum treated group (63.41%). Furthermore, nematode parasites responded poorly to synthetic drugs, although there was a 4.72% and 45.54% decrease in FEC in the albendazole and closantel-treated groups, respectively. Although no significant difference was found between the treatment groups, the P. quercetorum treated group showed a significant reduction in fecal egg count after treatment. Based on findings, a P. quercetorum based anthelmintic could be a sustainable alternative to combat parasite infestation. Therefore, further studies are needed to determine the optimal dose rate and frequency of doses required for effective control of gastrointestinal parasites in goats.

Antibacterial activity of closantel against methicillin-resistant Staphylococcus aureus and itsbiofilm. / æ°¯æ°°ç¢˜æŸ³èƒºå¯¹è€ç”²æ°§è¥¿æž—é‡‘é»„è‰²è‘¡è„çƒèŒåŠå ¶ç”Ÿç‰©è†œçš„æŠ—èŒæ´»æ€§.

OBJECTIVES: The antimicrobial resistance of Staphylococcus aureus (S. aureus) has become a challenge in the treatment of infectious diseases. It is of great clinical value to discovery effective antimicrobial agents against multi-drug resistant S. aureus and its biofilms. This study aims to explore the antibacterial activity of the antiparasitic drug closantel against methicillin-resistant S. aureus and its biofilms through drug repurposing. METHODS: The sensitivity of S. aureus to closantel was assessed using microbroth dilution and disk diffusion methods. The bacteriostatic and bactericidal activities of closantel were determined by time-kill curves and colony count. Scanning electron microscopy combined with SYTOX Green and DiSC3(5) fluorescence probes were used to study the bactericidal mechanism of closantel. The influence of resistance was assessed by continuous exposure to sub-inhibitory concentrations of closantel. The anti-biofilm activity was evaluated using 96-well plates and crystal violet staining, and cytotoxicity was measured using the CCK-8 assay. RESULTS: The minimal inhibitory concentration (MIC) of closantel for both methicillin-sensitive and methicillin-resistant S. aureus ranged from 0.125 to 1.000 µg/mL. Disk diffusion tests showed that 80 µg of closantel created an inhibition zone, which increased in diameter with higher drug amounts. Sub-inhibitory concentrations (0.031 µg/mL) of closantel significantly inhibited S. aureus proliferation, reducing bacterial turbidity from 0.26±0.00 to 0.11±0.01 (t=16.06, P<0.001), with stronger inhibition at higher concentrations. Closantel at 0.25×MIC inhibited S. aureus proliferation for 12 hours, while 1×MIC inhibited it for over 24 hours, with the number of viable bacteria decreasing as the drug concentration increased. Mechanistic studies indicated that closantel effectively disrupted the integrity of S. aureus cell membranes, significantly increasing SYTOX Green and DiSC3(5) fluorescence intensity. Even after 25 days of continuous exposure to sub-inhibitory concentrations of closantel, no resistance developed. Closantel at 0.0625 µg/mL significantly inhibited biofilm formation, reducing it from 1.29±0.16 to 0.62±0.04 (t=11.62, P<0.001), showing a clear dose-dependent effect. Closantel at 2 µg/mL also significantly eradicated established biofilms, reducing biofilm mass from 1.62±0.34 to 0.51±0.39 (t=4.84, P<0.01). Additionally, closantel exhibited extremely low cytotoxicity, with half-maximal lethal concentrations for HepG2 liver cancer cells and normal LO2 liver cells both exceeding 64 µg/mL. CONCLUSIONS: Closantel exhibits strong antibacterial activity against S. aureus and its biofilm with low cytotoxicity against human cells, making it a promising candidate for new therapeutic strategies against S. aureus-related infections.

Synergistic antibacterial effects of closantel and its enantiomers in combination with colistin against multidrug resistant gram-negative bacteria.

Drug combinations and repurposing have recently provided promising alternatives to cope with the increasingly severe issue of antibiotic resistance and depletion of natural drug molecular repertoires that undermine traditional antibacterial strategies. Closantel, an effective adjuvant, reverses antibiotic resistance in gram-negative bacteria. Herein, the combined antibacterial enantioselectivity of closantel is presented through separate enantiomer studies. Despite yielding unexpected differences, two closantel enantiomers (R, S) increased colistin activity against gram-negative bacteria both in vitro and in vivo. The fractional inhibitory concentration indices of R-closantel and S-closantel combined with colistin against Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli ranged from 0.0087 to 0.5004 and from 0.0117 to 0.5312, respectively. This difference was further demonstrated using growth inhibition assays and time-killing curves. Mechanistically, a higher intracellular concentration of R-CLO is more effective in enhancing the antimicrobial activity of combination. A mouse cutaneous infection model confirmed the synergistic stereoselectivity of closantel. This discovery provides novel insights for developing precision medication and containment of increasing antibiotic resistance.

Chiral separation of racemic closantel and ultratrace detection of its enantiomers in bacteria by enhanced liquid chromatography-tandem mass spectrometry combined with postcolumn infusion of ammonia.

Reliable analysis of ultratrace antibiotics in bacterial cells may become a new means to elucidate the antibacterial mechanism, drug resistance and environmental fate. In this work, an ultrahigh-sensitive, accurate and enhanced liquid chromatography-tandem mass spectrometric method was first developed for chiral separation and detection of racemic closantel, as an antibacterial adjuvant. Optimizing acetonitrile-water-formic acid system that is compatible with mass spectrometry as a mobile phase, the baseline separation of two enantiomers was achieved by using EnantioPak® Y1-R chiral column, and the resolution of the two analytes was more than 1.95. Further adopt the strategy of postcolumn infusion of ammonia, the mobile phase pH was reversed from acidic condition suitable for the optimal chromatographic separation of R- and S-closantel to alkaline, so that closantel could realize efficient electrospray ionization under the preferred negative ion mode. The bacterial cells were subjected to be frozen-cracked, and the analytes were extracted with acetonitrile after clipping the pointed bottom of the Eppendorf tube into a new tube. The method was linear over concentration ranges of 0.5-50 pg/mL (r2≥0.99) for R- and S-closantel. The detection limits of target analytes were all 0.15 pg/mL in bacterial cells. The average recoveries of two enantiomers ranged from 81.2% to 107.8% with relative standard deviations below 15%. The method proposed might be important support for the deep research of the stereoselectivity of biological activity, toxicity and metabolism of closantel enantiomers.

The first fluorescent sensor for the detection of closantel in meat.

Closantel is widely used in the management of parasitic infestation in livestock, but is contraindicated in humans due to its high toxic to human retina. Thus, development of a fast and selective method for the detection of closantel residues in animal products is highly needed yet still challenging. In the present study, we report a supramolecular fluorescent sensor for closantel detection through a two-step screening process. The fluorescent sensor can detect closantel with a fast response (<10 s), high sensitivity, and high selectivity. The limit of detection is 0.29 ppm, which is much lower than the maximum residue level set by government. Moreover, the applicability of this sensor has been demonstrated in commercial drugs tablets, injection fluids, and real edible animal products (muscle, kidney, and liver). This work provides the first fluorescence analytical tool for accurate and selective determination of closantel, and may inspire more sensor design for food analysis.

Comparison of the therapeutic efficacy of five anthelmintics against natural Fasciola hepatica infections in dairy cattle from the Mantaro Valley, Peru.

The intensive use of anthelmintic drugs to control Fasciola hepatica infections in dairy cattle has resulted in the emergence of anthelmintic resistance. Cases of resistance to triclabendazole (TCBZ) have been reported worldwide. The main goal of this research was to evaluate the main five fasciolicides to control fasciolosis in dairy cattle in the Mantaro Valley, Peru. Two fecal egg count reduction tests were performed. In a first study, 24 naturally F. hepatica infected cattle were randomly grouped into three experimental groups (n = 8). Groups were treated with either TCBZ, nitroxynil (NTX) or closantel (CLOS). In a second experiment, 55 naturally infected cows were grouped into three experimental groups and treated with either TCBZ (n = 18), rafoxanide (RFX) + albendazole (ABZ) (n = 19) or clorsulon (CLN) + ivermectin (IVM) (n = 18). Therapeutic efficacy was determined following the WAAVP guidelines by measuring reduction in fluke egg output at days 15 and 30 post-treatment. Bootstrapping method was used to obtain the 95% confidence intervals. The efficacy of TCBZ was inadequate in both studies (≤80.8%). Closantel showed high efficacy (≥ 90%) at both days, while NTX showed 92.9% (83-100) and 82.1% (53.6-100), efficacy, at days 15 and 30, respectively. Efficacy for RFX were 92.1% (79.6-98.9) and 97.4% (94.1-99.4); and for CLN, 98.8% (97.6-100) and 80.1% (44.7-99.4), at days 15 and 30, respectively. The outcome of this study indicates reduced therapeutic efficacy of TCBZ against F. hepatica in an important dairy area of the Peruvian central highlands but also demonstrates the validity of four alternatives.

Residues of an anthelmintic veterinary drug (closantel) detected in red foxes (Vulpes vulpes) in Scotland.

The contamination of the environment by some veterinary medicines and their impact on wild animals is of increasing concern. However, there is a lack of information about their residues in wildlife. The sentinel animals most commonly used for monitoring the level of environmental contamination are birds of prey, and information on other carnivores and scavengers scarce. This study examined the livers from 118 foxes for residues of a range of 18 veterinary medicines (16 anthelmintic agents and 2 metabolites) used on farm livestock. The samples were collected from foxes, primarily in Scotland, shot during legal pest control activities conducted between 2014 and 2019. Closantel residues were detected in 18 samples, and the concentrations found ranged from 6.5 µgkg-1 to 1383 µgkg-1. No other compounds were found in significant quantities. The results show a surprising frequency and level of closantel contamination, raising concerns about both the route of contamination and the potential impacts on wild animals and the environment, such as the potential for significant wildlife contamination to contribute to the development of closantel-resistant parasites. The results also suggest that red fox (Vulpes vulpes) could be a useful sentinel species for detecting and monitoring some veterinary medicine residues in the environment.

Calicophoron daubneyi (Dinnik, 1962) (Digenea) in beef and dairy cattle in the Czech Republic: prevalence and drug efficacy.

A total of 1,724 beef and 2,941 dairy cattle older than one year from 66 beef and 67 dairy farms in the Czech Republic were examined for the presence of rumen and liver fluke eggs in 2019-2022. Out of 227 positive animals, all were positive for paramphistome and five for fasciolid eggs. Molecular analysis of the ITS2 rDNA revealed the presence of Calicophoron daubneyi (Dinnik, 1962) and Fasciola hepatica Linnaeus, 1758. Faecal egg count (FEC) showed low infection intensity (12 EPG) in animals infected with F. hepatica and high variability in C. daubneyi infections (2-589 EPG). Efficacy of oxyclozanide, albendazole, ivermectin, and closantel against C. daubneyi infection was evaluated at eight beef cattle herds. Faecal samples were collected from all positive animals at 0 and 21days post-treatment. Based on FEC, albendazole, ivermectin and closantel reduced the number of C. daubneyi eggs shed by 0-9.9%, with no effect on the number of infected animals. The use of oxyclozanide on two beef farms showed 100% efficacy against C. daubneyi and F. hepatica. Follow-up examination 5-6 months after drug application showed reinfection of most animals with C. daubneyi, but the FEC was significantly lower. The finding of four dairy cows infected with C. daubneyi housed in a stable without pasture suggests the possibility of the infection being introduced through roughage.

Determination of closantel enantiomers in black goat plasma and their pharmacokinetic characteristics.

Closantel is a broad-spectrum antiparasitic drug widely used in livestock. It is a chiral drug consisting of a pair of enantiomers. An accurate, selective, and validated method was established for separating and detecting closantel enantiomers in black goat plasma. Separation of enantiomers was achieved in Chiralpak AD-3 based on amylose tris (3,5-dimethyl phenyl carbamates) under a gradient mobile phase composed of n-hexane-TFA (100:0.1, v/v) and IPA-MeOH-TFA (99:1:0.1, v/v/v). Mean recoveries of the two enantiomers at three spiking levels ranged from 97.4 % to 102.0 % with a relative standard deviation ≤ 4.5 %. The limit of quantification was 1.35 µg/mL for each enantiomer in plasma. The proposed method was successfully applied to investigate the enantioselective pharmacokinetics of closantel enantiomers (E1 and E2) in black goats following an intramuscular closantel sodium at 5 mg/kg b.w. The results revealed that peak plasma concentration and area under the curve were significantly different between the two enantiomers (p < 0.05). Cmax and AUC0-∞ for closantel E1 were approximately 3 times greater than closantel E2. These findings would help in further evaluation of pharmacokinetic, pharmacodynamic, and toxicity of the individual enantiomers of closantel in food animals.

Effectiveness of Anthelmintic Treatments in Small Ruminants in Germany.

Widespread anthelmintic resistance is a concern for small ruminant health and production worldwide. The current situation regarding anthelmintic efficacy is, however, not very well studied in Germany. Thus, a nationwide field study was undertaken to assess the effectiveness of 253 treatments performed in 223 small ruminant flocks by faecal egg count reduction test (FECRT) using pooled samples and a modified McMaster method. The percentage of Haemonchus contortus and non-Haemonchus eggs was determined by fluorescence microscopy following peanut agglutinin-fluorescein isothiocyanate staining. Treatments were chosen and performed by farmers together with their local veterinarian, and potentially confounding factors for FECRT results were addressed as far as possible by rigorous inclusion criteria. Reduced effectiveness was observed for treatments with all examined anthelmintic classes, but treatments with benzimidazoles and moxidectin showed significantly poorer results than monepantel, a closantel and mebendazole combination, and levamisole. Low case numbers precluded reliable assessment of avermectins. Unsuccessful treatments were frequently associated with the survival of H. contortus, but this was also observed for non-Haemonchus genera. The results are highly concerning, and sustainable approaches to parasite control are urgently needed to prevent further deterioration of this situation.

Quantitative Analysis of Abamectin, Albendazole, Levamisole HCl and Closantel in Q-DRENCH Oral Suspension Using a Stability-Indicating HPLC-DAD Method.

Combination therapy of many anthelmintic drugs has been used to achieve fast animal curing. Q-DRENCH is an oral suspension, containing four different active drugs against GIT worms in sheep, commonly used in Australia and New Zeeland. The anti-parasitic drugs are Albendazole (ALB), Levamisole HCl (LEV), Abamectin (ABA), and Closantel (CLO). The main purpose of this study is to present a new simultaneous stability-indicting HPLC-DAD method for the analysis of the four drugs. The recommended liquid system was 1 mL of Triethylamine/L water, adjusting the pH to 3.5 by glacial acetic acid: acetonitrile solvent (20:80, v/v). Isocratic elusion achieved the desired results of separation at a 2 mL/min flow rate using Zorbax C-18 as a stationary phase. Detection was performed at 210 nm. The linearity ranges were 15.15 to 93.75 µg/mL for ALB, 25 to 150 µg/mL for LEV, 30 to 150 µg/mL for ABA, and 11.7 to 140.63 µg/mL for CLO. Moreover, the final greenness score was 0.62 using the AGREE tool, which reflects the eco-friendly nature. Moreover, the four drugs were determined successfully in the presence of their stressful degradation products. This work presents the first chromatographic method for simultaneous analysis for Q-DRENCH oral suspension drugs in the presence of their stressful degradation products.

Effects of Ferula asafetida, closantel, albendazole, oxfendazole, and ivermectin against Haemonchus contortus in goats and sheep.

BACKGROUND: Haemonchosis is a fatal disease of small ruminants caused by the parasite Haemonchus contortus (H. contortus). The most common drugs used in the treatment of H. contortus include albendazole, oxfendazole, and ivermectin. However, as previously reported in the treatment of haemonchosis, these medicines have acquired drug resistance problems over time. Interestingly, natural plant compounds have demonstrated promising effects in the treatment of H. contortus. Therefore, the current study evaluated the effects of plant extract, Ferula asafetida, against common drugs such as albendazole, oxfendazole, ivermectin, and closantel for the treatment of haemonchosis in small ruminants. METHODOLOGY: The current study was conducted on different small ruminant farms in Kasur District, Punjab, Pakistan. The positive animals (n = 720) after coprological examination were selected in this study and divided into two major groups (n = 360 goats and n = 360 sheep). Further, animals were divided into five treatment groups (A-E) and one control group with no treatment (F). Albendazole, oxfendazole, ivermectin, closantel, and Ferula asafetida were administered orally to groups A-E, respectively. The eggs per gram feces (EPG) were determined through the McMaster technique on days 0, 7th, and 14th of treatment. RESULTS: The results showed a significantly higher efficacy of closantel and Ferula asafetida against H. contortus in both goats (100% and 70%; p < 0.05) and sheep (99% and 87%; p < 0.05), respectively. No correlation was observed between EPG reduction with age and gender in both goats and sheep. CONCLUSION: Allopathic drug closantel and herbal drug, Ferula asafetida, have been proved an effective dewormer against H. contortus in small ruminants.

Reversible blindness after erroneous prescription of closantel: A case report.

A 20-year-old girl was referred with vision loss upon closantel use. Plasma exchange and high-dose corticosteroid pulse therapy were administered. A 2.5-year follow-up showed improved vision and increased layer thickness of the peripheral nerve fiber. Early treatment with plasma exchange and high-dose corticosteroid therapy can be beneficial to reverse closantel toxicity.

Analytical Separation of Closantel Enantiomers by HPLC.

Closantel is an antiparasitic drug marketed in a racemic form with one chiral center. It is meaningful to develop a method for separating and analyzing the closantel enantiomers. In this work, two enantiomeric separation methods of closantel were explored by normal-phase high-performance liquid chromatography. The influences of the chiral stationary phase (CSP) structure, the mobile phase composition, the nature and proportion of different mobile phase modifiers (alcohols and acids), and the column temperature on the enantiomeric separation of closantel were investigated in detail. The two enantiomers were successfully separated on the novel CSP of isopropyl derivatives of cyclofructan 6 and n-hexane-isopropanol-trifluoroacetic acid (97:3:0.1, v/v/v) as a mobile phase with a resolution (Rs) of about 2.48. The enantiomers were also well separated on the CSP of tris-carbamates of amylose with a higher Rs (about 3.79) when a mixture of n-hexane-isopropanol-trifluoroacetic acid (55:45:0.1, v/v/v) was used as mobile phase. Thus, the proposed separation methods can facilitate molecular pharmacological and biological research on closantel and its enantiomers.

Changes in Serum Thiol-Disulphide Homeostasis in Sheep with Gastrointestinal Nematodes.

This work aimed to evaluate the thiol-disulphide homeostasis in serum of lambs naturally infected by gastrointestinal nematodes presenting different levels of parasite load indirectly indicated by faecal worm egg counts (EPG). Furthermore, the possible changes in the thiol-disulphide dynamic after different procedures to reduce the parasitic charge, such as the integrated crop-livestock system or anthelmintic treatment, were assessed. The results were compared with a panel of various oxidative stress and inflammatory biomarkers. The lambs were divided into three groups: animals highly infected (EPG higher than 5000) and packed cell volume (PCV) lower than 24% (G1); animals highly infected (EPG higher than 5000) and normal PCV (>24%) (G2); and animals presenting EPG lower than 5000 and normal PCV (>24%) (G3). The highly infected lambs (G1 and G2) showed lower total thiol (TT) and native thiol (SH) (p ≤ 0.01) than those from G3. After treatment, TT and SH increased significantly in all groups (p ≤ 0.01), and the disulphide (SS)/TT and SS/SH ratios decreased significantly (p < 0.01) in G1 and G2. These results show that the thiol-disulphide balance was impaired in lambs infected by gastrointestinal nematodes and that it could be potentially used as a biomarker to monitor this disease.

Effectiveness of an experimental injectable prodrug formulation against Fasciola hepatica of different ages in experimentally infected sheep.

In this work, we present an evaluation of the fasciolicidal efficacy of a new injectable formulation of fosfatriclaben in comparison with the subcutaneous closantel and oral triclabendazole formulations currently used in veterinary practice as fasciolicides. The study was carried out in vivo on Fasciola hepatica at 2, 4, 6 and 8 weeks of age in experimentally infected sheep. To evaluate the formulation, the percent reduction of the parasite load was measured and the number of fluke eggs. Fosfatriclaben was used at 6 mg/kg/IM (dose equivalent to triclabendazole content), closantel at 5% at 10 mg/kg/SC, and triclabendazole at 10 mg/kg/PO; the control group received no treatment. Fosfatriclaben showed fasciolicidal efficacies of 95.5 %, 100 %, 100 % and 100 %, and triclabendazole showed similar efficacies of 97.4 %, 100 %, 100 % and 100 %, at the different treatment weeks (P > 0.05). Closantel showed limited efficacy against 2-, 4- and 6-week-old flukes but 100 % efficacy in adult flukes. All three evaluated formulations eliminated all 8-week-old F. hepatica trematode eggs. Although fosfatriclaben and triclabendazole showed similar fasciolicidal efficacy, the intramuscular administration of fosfatriclaben has several advantages over the oral administration of triclabendazole, such as ease of administration for veterinary use and a reduced risk of accidents for both the operator and the animals. In addition, the dose used in this injectable formulation is only 60 % of the oral dose, which reduces environmental contamination.

Case report: restored vision after ocular Closantel intoxication and blindness.

BACKGROUND: Closantel is the best-known anti-parasitic medicine for veterinarians, which is contraindicated in humans. After reviewing the literature on ocular toxicity following mistaken usage of Closantel in humans, this report was found as the first complete restoration of visual function after Closantel intoxication. This report could be useful in anticipating the possibility of a further improvement based on a dose-response relationship. An important point of this report is the apparent reversibility of the vision and Electrophysiological parameters after Closantel intoxication and blindness. To conclude, the present case report demonstrates the importance of immediate referral and management in Closantel intoxication to avoid the long-term adverse effects of drug on visual function. CASE PRESENTATION: A 47-year-old man mistakenly took about 20 cc of Closantel 5% (15.87 mg/kg). Four hours after mistaken usage of Closantel, he was transferred to the district hospital due to dizziness and nausea. His stomach was washed out immediately after hospital arrival. He was being hospitalized in that hospital for 3 days. Then, he was referred to our clinic due to progressive vision loss. Methylprednisolone acetate 250 mg was injected once on 5th day after taking Closantel. His vision was reducing gradually so low that he could only detect hand motion (HM) on the 14th day after taking Closantel. ERG test was requested. It showed an exclusive reduction in b-wave amplitude under photopic and scotopic conditions. Later, his vision surprisingly improved gradually and his visual acuity was fully restored on the 28th day after the incident. After 3 years, we checked him again. His visual acuity was 20/20 in both eyes and the patient did not have any problem and his ERG report was completely normal. CONCLUSIONS: In low dose of Closantel and immediate referral, ocular toxicity could be resolved.

Efficacy of Oxyclozanide and Closantel against Rumen Flukes (Paramphistomidae) in Naturally Infected Sheep.

Paramphistomosis is considered an emergent disease of ruminants in Europe. Some drugs have been found effective for treating paramphistomid infections in cattle, but data in sheep are currently limited. Thus, faecal samples from 25 adult sheep naturally infected with paramphistomids were collected weekly to test the efficacy of oxyclozanide and closantel. Three groups were performed: nine animals orally treated with a single dose of oxyclozanide (15 mg/kg bodyweight (BW) integrated the G-OXI group, whereas eight sheep orally treated with a single dose of closantel (10 mg/kg BW) were placed in a group called G-CLS. Eight untreated controls constituted the group G-CON. Oxyclozanide showed efficacies up to 90% until week 11 post-treatment, with a maximum efficacy of 98.3%, and significant differences were found between G-OXI and G-CON until the 26th week post-treatment. Closantel was insufficiently active (0-81%) throughout the study and differences compared to G-CON were never found. The present study reveals that oxyclozanide given at a single oral dose of 15 mg/kg BW is highly effective against adult rumen flukes in sheep. In addition, the use of a single oral dose of closantel at 10 mg/kg BW is not recommended for treating paramphistomid infections in sheep.

Multiple anthelmintic resistance in gastrointestinal nematodes of Caprines on Mountain Research Centre for Sheep and Goat at Kashmir Valley, India.

The study was conducted to evaluate the status of anthelmintic resistance in Gastro-Intestinal Nematodes (GINs) of goats at an organized farm located in Kashmir, as there is no report of resistance against these parasites of goats from this temperate region, although it has been reported worldwide including India. Caprines reared at this farm exhibited reduced efficacy to multiple anthelmintics following treatments with Fenbendazole (FBZ), Closantel and Ivermectin (IVM) in Faecal Egg Count Reduction Test (FECRT). The results suggested that the overall efficacy was highest for IVM at 83.5% and 90.0% on 7th and 14th day post-treatment, respectively and least for FBZ at 44.3% and 62.5%, respectively, whereas the corresponding figures for closantel were 68.3% and 86.2%, respectively. The pre-treatment faecal culture revealed Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus colubriformis as predominant strongyles, however, in post-treatment samples, only H. contortus was observed. Further, the infective larvae were subjected to Allele specific PCR (AS-PCR) for accurate diagnosis of BZ resistance. The AS-PCR revealed 52% of H. contortus were homozygous resistant (rr) and 17% were heterozygous (rS) on day "0" before treatment and 100% homozygous resistant (rr) on 7th day post treatment. In both T. colubriformis and T. circumcincta, 100% population was homozygous susceptible (SS) at day "0" before treatment. The overall frequency of resistant (r) allele for H. contortus was 60.5% and for susceptible allele (s) was 39.5%. For T. colubriformis and T. circumcincta the frequency of susceptible allele (s) was 100%. The survey indicated that the GINs of goats on the farm have developed multiple anthelmintic resistance to FBZ, closantel and IVM and the condition is alarming in the farm. Moreover surveillance studies about status of anthelmintic resistance in other farms (Govternment as well as Private) of Kashmir valley should be carried out at large scale to develop effective and sustainable control strategies against GI Nematodes.

Selective determination of closantel by artificial neural network-genetic algorithm optimized molecularly imprinted polypyrrole using UV-visible spectrophotometry.

A molecularly imprinted polymer (MIP) for the selective solid-phase extraction (SPE) was prepared applying polymerization of pyrrole monomer in the presence of closantel (CLS) as a template molecule. The quantitative measurements were carried out using UV-Vis spectrophotometry. Several important parameters control the performance of polypyrrole sorbent. The influence of seven factors including loading time, polymerization time, amount of sorbent, stirring rate, desorption time, initiator concentration and monomer to template ratio were investigated. The optimization of parameters was performed using Plackett-Burman design (PBD), central composite design (CCD), artificial neural network (ANN) and genetic algorithm (GA). The Pareto plot showed that the effects of loading time, reaction time and amount of sorbent are most important to the process. These significant factors were investigated using CCD and the obtained data were used to train the ANN. The predicted model obtained from the trained ANN was introduced to GA as the fitness function to be optimized. The calibration curve demonstrated linearity over a concentration range of 0.010-10 mM with a correlation coefficient (R2) of 0.9833 under optimal condition. The synthesized MIP sorbent showed a good selectivity and sensitivity toward CLS. The limit of detection (LOD) for CLS was obtained 1.0 µM. The real sample analysis was performed to determine CLS in pharmaceutical and human serum samples.