ABSTRACT
The production of tambaqui Colossoma macropomum has been undergoing financial losses due to parasitic infection by the acanthocephalan Neoechinorhynchus buttnerae, raising an alert for aquaculture in South America. The lack of adequate treatment and use of unlicensed chemicals encourages research for alternative solutions with minimal side effects. The objectives of this study were to evaluate the in vitro antiparasitic potential of commercial nutraceutical products (Natumix® and BioFish®) against N. buttnerae and to assess the respective in vivo toxic effects on the host tambaqui. For in vitro assays, parasitized fish were necropsied for acanthocephalans sampling. The parasites were exposed to three concentrations (0.078, 0.313 and 1.25 mg/ml) of each product, as well as controls (one without product and another with a solubilizer). For the in vivo acute toxicity test, juvenile fish (<0.1 g) were exposed to five increasing concentrations of each product. Mortality of tambaqui was recorded at 24, 48, 72 and 96 h. The estimated lethal concentration (LC) for 10, 50, 90 and 99% of fish was determined to classify the toxicity of the products on the target species. After in vitro efficacy tests, the highest concentrations (1.25 mg/ml) caused 100% mortality of the parasites in both products, but only Natumix® caused 100% mortality using the intermediate concentration (0.313 mg/ml) after 24 h. According to the acute toxicity result, the LC50 classified the nutraceutical products as slightly toxic for tambaqui. The tested products had a parasiticidal effect on N. buttnerae, and the toxicity test showed that both products have therapeutic potential when added to the diet.
Subject(s)
Acanthocephala/drug effects , Anthelmintics/pharmacology , Characiformes/parasitology , Dietary Supplements/analysis , Fish Diseases/parasitology , Helminthiasis, Animal/parasitology , Acanthocephala/physiology , Animals , Anthelmintics/analysis , Anthelmintics/toxicity , Aquaculture , Characiformes/growth & development , Fish Diseases/drug therapy , Helminthiasis, Animal/drug therapy , Lethal Dose 50 , South AmericaABSTRACT
The gastrointestinal nematodes (GIN) stand out as an important cause of disease in small ruminant, especially on goat farm. Widespread resistance to synthetic anthelminthics has stimulated the research for alternative strategies of parasite control, including the use of medicinal plants. The present work summarizes the in vitro and in vivo studies of plants with activity against GIN of goats, focusing on the description of chemical constituents related to this effect. This review retrieved 56 scientific articles from 2008 to 2018 describing more than 100 different plant species. The most frequently investigated family was Fabaceae (30.7%). Most in vitro studies on the activity of plant extracts and fractions were carried out with of free-living stages nematodes. In vivo studies were conducted mainly with the use of plants in animal feed and generally showed lower effectiveness compared to in vitro assays. The main plant secondary metabolites associated with anthelmintic effect are condensed tannins, saponin and flavonoids. However, the studies with compounds isolated from plants and elucidation of their mechanisms of action are scarce. Herbal medicines are thought to be promising sources for the development of effective anthelmintic agents.
Subject(s)
Anthelmintics/pharmacology , Goat Diseases/parasitology , Helminthiasis, Animal/parasitology , Intestinal Diseases, Parasitic/veterinary , Nematoda/drug effects , Nematode Infections/veterinary , Plant Extracts/pharmacology , Animals , Anthelmintics/isolation & purification , Anthelmintics/therapeutic use , Goat Diseases/drug therapy , Goats , Helminthiasis/drug therapy , Helminthiasis/parasitology , Helminthiasis, Animal/drug therapy , Intestinal Diseases, Parasitic/drug therapy , Intestinal Diseases, Parasitic/parasitology , Nematoda/isolation & purification , Nematode Infections/drug therapy , Nematode Infections/parasitology , Parasitic Sensitivity Tests , Plant Extracts/isolation & purification , Plant Extracts/therapeutic use , Plants, Medicinal/chemistry , Treatment OutcomeABSTRACT
This study aimed to assess current worm control practices used by Australian alpaca farmers with an online questionnaire survey. The questionnaire contained questions about farm demography and general husbandry practices, farmers' knowledge about gastrointestinal nematodes (GINs) and their importance, the use of worm control strategies and anthelmintics, and grazing management. A link for the questionnaire survey was sent to all (n = 954) registered members of the Australian Alpaca Association in July 2015. The response rate for the questionnaire was 25% (239/954). The majority of respondents were from small (≤ 50 alpacas; 64%, 153/239) followed by medium (50-100 alpacas; 24%, 57/239) and large (>100 alpacas; 12%, 29/239) farms. Findings revealed that the majority of respondents kept Huacaya alpacas to produce high-quality fibre and alpacas were usually kept with other domestic ruminants (e.g. cattle and sheep). Although half of alpaca farmers (114/220) perceived that GINs were an important health problem of alpacas, with Haemonchus spp. being the most common nematode, the majority of them (174/220) used anthelmintics for nematode control. Macrocyclic lactones, a commercial combination of four anthelmintics (abamectin, albendazole, closantel and levamisole) and monepantel were the three most commonly used dewormers by Australian alpaca farmers. Although a significant proportion (166/213) of respondents used a quarantine drench for alpacas, very few respondents were aware of strategic deworming and the issue of anthelmintic resistance. Alpaca farmers mostly used anthelmintics at the dose rate recommended for sheep (47%, 79/167) and cattle (9%, 15/167), though some used 1.5 (31%, 51/167) and 2 (13%, 22/167) times the dose rate recommended for sheep. The majority of small herds used anthelmintics at the dose rate recommended for sheep and cattle while medium and large herds used anthelmintics at 1.5 to 2 times the dose rate recommended for sheep. This study provides invaluable insights into the demography of alpaca farms in Australia, husbandry practices used by alpaca farmers and their knowledge about worms and their control, thereby paving the way for developing guidelines for the control of GINs of alpacas.
Subject(s)
Animal Husbandry , Anthelmintics/therapeutic use , Camelids, New World , Helminthiasis, Animal/prevention & control , Animals , Australia , Data Collection , Farmers , Helminthiasis, Animal/drug therapy , Surveys and QuestionnairesABSTRACT
In this study, we evaluated the in vivo comparative efficacy of ivermectin and Nigella sativa extract against helminths in Aseel chickens, and the effects of helminths on blood parameters before and after treatment in Aseel chickens. Forty naturally infected adult Aseel chickens were randomly divided into four groups (n = 10 each): group A (ivermectin at 300 µg/kg); group B (N. sativa extract at 200 mg/kg); group C (ivermectin at 300 µg/kg + N. sativa extract at 200 mg/kg); group D was kept as a positive control to monitor time-related changes. On day 28 post treatment, the mean percentages of faecal egg-count reduction (FECR %) in groups A, B and C were recorded as 93.58, 88.09 and 100.00%, respectively. Further data analysis showed significantly higher efficacy in group C (100 ± 0.00%) than in groups A and B (P < 0.001). Highly significant (P < 0.001) improvements in mean percentage values of packed cell volume (PCV %) were recorded in groups A and C on days 14 and 28 post treatment. Meanwhile, the improvements in mean values of haemoglobin (Hb) concentration in groups A, B and C were highly significant (P < 0.001) when compared to that of group D on day 28 post treatment. The synergistic combination of ivermectin and N. sativa extract possessed greater efficacy than either ivermectin or N. sativa extract used alone. Furthermore, both PCV % and Hb concentration values gradually increased in the treated groups compared to the control group, in which PCV % and Hb concentration gradually decreased throughout the trial.
Subject(s)
Helminthiasis, Animal/drug therapy , Ivermectin/therapeutic use , Nigella sativa/chemistry , Plant Extracts/therapeutic use , Animals , Chickens/parasitology , Drug Synergism , Feces/parasitology , Helminths/drug effects , Parasite Egg Count , Random AllocationABSTRACT
The toxicity of water-ethanol extracts of garlic (Allium sativum), ginger (Zingiber officinale), basil (Ocimum basilicum), bitter chaparro (Castela tortuousa), onion (Allium cepa) and papaya (Carica papaya) against adults, eggs and oncomiracidia of Neobenedenia spp. parasites was examined. Parasites were exposed to continuous immersion and treated as follows: extracts were tested at three dilutions: 1:10, 1:50 and 1:100 made with filtered seawater (35 g l-1); ethanol (70%) was evaluated at the same dilutions of 1:10 (7% ethanol), 1:50 (1.4% ethanol) and 1:100 (0.07% ethanol) and a seawater (35 g l-1) control. The antiparasitic effect was measured on: (1) adult survival, egg production and time to detachment from the culture vessel; (2) egg development and cumulative egg hatching; and (3) oncomiracidia survival. All three dilutions of ginger and dilutions 1:100 and 1:50 of basil extract reduced adult survival in vitro, time to detachment from the surface of the culture vessel, egg production and oncomiracidia survival. Bitter chaparro extract reduced adult egg production and oncomiracidia survival. Hatching success was significantly reduced (P < 0.05) in basil extract (1:100) to 86.6% compared to the seawater control (100%). Dilutions 1:10 of ginger and basil exhibited the highest impact on the biological parameters of Neobenedenia sp. Our study demonstrates that water-ethanol extracts of ginger, basil and bitter chaparro are toxic against Neobenedenia sp. life stages.
Subject(s)
Ectoparasitic Infestations/veterinary , Fish Diseases/drug therapy , Helminthiasis, Animal/drug therapy , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Trematoda/drug effects , Animals , Antiplatyhelmintic Agents/pharmacology , Antiplatyhelmintic Agents/therapeutic use , Ectoparasitic Infestations/drug therapy , Ectoparasitic Infestations/parasitology , Fish Diseases/parasitology , Helminthiasis, Animal/parasitology , Magnoliopsida/chemistry , Ovum/drug effects , Ovum/physiology , Trematoda/physiologyABSTRACT
Gastrointestinal nematodes are a major threat to small ruminant rearing in the Sahel area, where farmers traditionally use bioactive plants to control these worms, including Acacia nilotica and Acacia raddiana. The main aim of this study was to screen the potential anthelmintic properties of aqueous and acetone extracts of leaves of these two plants based on three in vitro assays: (1) the egg hatch inhibition assay (EHA); (2) the larvae exsheathment inhibition assay (LEIA) using Haemonchus contortus as a model; and (3) an adult mortality test (AMT) applied on Caenorhabditis elegans. For the EHA, only A. raddiana was effective with IC50 = 1.58 mg/mL for aqueous extract, and IC50 = 0.58 mg/mL for acetonic extract. For the LEIA, all extracts inhibited the exsheathment of larvae compared to the controls, and the aqueous extract of A. nilotica was more larvicidal with IC50 = 0.195 mg/mL. In general, all responses to the substances were dose-dependent and were significantly different from the control group (p < 0.05). For the AMT, the extracts of the two Acacia species were effective but A. raddiana showed greater efficacy with 100% mortality at 2.5 mg/mL and LC50 = 0.84 mg/mL (acetonic extract). The addition of polyvinyl polypyrrolidone (PVPP) to the extracts suggested that tannins were responsible for blocking egg eclosion and inducing adult mortality but were not responsible for exsheathment inhibition. These results suggest that the leaves of these Acacia species possess ovicidal and larvicidal activities in vitro against H. contortus, and adulticidal effects against C. elegans.
Subject(s)
Acacia/chemistry , Anthelmintics/pharmacology , Goat Diseases/drug therapy , Helminthiasis, Animal/drug therapy , Phytotherapy/veterinary , Plant Extracts/pharmacology , Animals , Anthelmintics/isolation & purification , Caenorhabditis elegans/drug effects , Feces/parasitology , Goat Diseases/parasitology , Goats , Haemonchiasis/drug therapy , Haemonchiasis/veterinary , Haemonchus/drug effects , Inhibitory Concentration 50 , Larva/drug effects , Lethal Dose 50 , Ovum/drug effects , Plant Extracts/isolation & purification , Polyphenols/analysis , Povidone/analogs & derivatives , Povidone/pharmacology , Proanthocyanidins/analysis , Proanthocyanidins/pharmacology , Tannins/analysis , Tannins/pharmacologyABSTRACT
Monogenean parasites are important ectoparasites of fish, and are responsible for severe economic impacts in the aquaculture industry. They are usually treated with chemicals, but the chemicals can have harmful side effects in the fish and may pose threats to human health. Rosemary (Rosmarinus officinalis) is a common medicinal herb, with antimicrobial and antitumor properties. Here, we examined the anthelmintic activity of rosemary extract against the monogenean (Dactylogyrus minutus) in vitro and in vivo using bath treatment and oral administration. The in vitro experiments showed that parasite survival was affected by both rosemary extract concentration and the solvent (water and ethanol). Parasites were dead at 61.8±5.6 and 7.8±1.4min when exposed to 100 and 200g aqueous rosemary extract solution/L of water respectively. It took 166.7±48.2 and 5.4±1.01min to kill the parasites when exposed to 1 and 32g ethanol rosemary extract solution/L of water respectively. Moreover, pure component of rosemary extract obtained commercially used in in vitro experiments showed that 1,8-Cineole was the most toxic component of the main components tested. Parasite intensity and prevalence in fish exposed to 50 and 100g aqueous rosemary solution/L water for 30min were significantly lower than they were in controls (p<0.05). In oral treatment experiments, diets of Cyprinus carpio were supplemented with eight different concentrations of aqueous rosemary extract. The intensity of parasites was significantly less in fish fed for 30days with feed containing 60, 80 and 100ml aqueous extract/100g feed than in control (p<0.05). Together these results indicate that rosemary is a promising candidate for prevention and control of monogenean infection.
Subject(s)
Anthelmintics/pharmacology , Carps/parasitology , Fish Diseases/drug therapy , Helminthiasis, Animal/drug therapy , Plant Extracts/pharmacology , Rosmarinus/chemistry , Animals , Anthelmintics/chemistry , Anthelmintics/isolation & purification , Aquaculture , Cyclohexanols/chemistry , Cyclohexanols/isolation & purification , Cyclohexanols/pharmacology , Eucalyptol , Fish Diseases/parasitology , Fish Diseases/prevention & control , Helminthiasis, Animal/parasitology , Helminthiasis, Animal/prevention & control , Monoterpenes/chemistry , Monoterpenes/isolation & purification , Monoterpenes/pharmacology , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Plants, Medicinal , Platyhelminths/drug effectsABSTRACT
The last half-century has provided all of the (few) drugs currently used to treat human helminthiases. Concern regarding the long-term utility of these drugs, given how readily resistance evolves in the veterinary-agricultural sector, spurs the discovery of new chemical entities. We review the approaches and technologies in use to identify anthelmintics and discuss a number of drug discovery paradigms that may prove pivotal to the next half-century of anthelmintic development.
Subject(s)
Anthelmintics/therapeutic use , Drug Discovery/trends , Helminthiasis/drug therapy , Helminths/drug effects , Animals , Drug Discovery/methods , Drug Evaluation, Preclinical/methods , Drug Evaluation, Preclinical/trends , Drug Therapy, Combination , Helminthiasis, Animal/drug therapy , Helminths/classification , Humans , PhenotypeABSTRACT
Disease caused by the parasitic helminths Dactylogyrus spp. results in significant economic damage to the aquaculture industry. Treatment using common chemicals (e.g. formalin) is usually dissatisfactory due to environmental problems, risk of residues, toxicity to fish, and the possibility of anthelmintic resistance. The search for an alternative drug is thus becoming more urgent. This study was designed to evaluate in vivo the anthelmintic efficacy of total saponin (TS), saikosaponin a (SSa), and saikosaponin d (SSd) from radix bupleuri (i.e. the dried root of Bupleurum sp.) based on our previous screening works, with the aim of determining which has commercial potential. Results showed that median effective concentration (EC50) values for TS, SSa, and SSd were 2.01, 1.46, and 0.74 mg l⻹, respectively. The acute toxicities against goldfish Carassius auratus for TS, SSa, and SSd were also determined, with median lethal concentration (LC50) of 8.99, 11.20, and 1.54 mg l-1, respectively. The resulting therapeutic indices (TIs) indicated that SSa (TI = 7.67) is a potential therapeutic agent for treating Dactylogyrus infection.
Subject(s)
Anthelmintics/therapeutic use , Bupleurum/chemistry , Fish Diseases/parasitology , Helminthiasis, Animal/parasitology , Oleanolic Acid/analogs & derivatives , Platyhelminths/classification , Saponins/therapeutic use , Animals , Anthelmintics/chemistry , Fish Diseases/drug therapy , Goldfish , Helminthiasis, Animal/drug therapy , Molecular Structure , Oleanolic Acid/chemistry , Oleanolic Acid/therapeutic use , Plant Roots/chemistry , Saponins/chemistryABSTRACT
BACKGROUND: Diseases caused by bacteria remain a major challenge globally and particularly in sub-Saharan Africa. The plants used in this study have been used in South Africa to treat helminth infections in livestock and humans. In a previous study we found a correlation between antifungal and anthelmintic activity in some cases. In this study we examined other potential uses of these thirteen plant species by determining the antibacterial and antioxidant activity of the leaf acetone extracts.The antibacterial activity was determined by using a serial microdilution method against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis. Bioautography was used to determine the number of antibacterial compounds. The antioxidant activity was determined using the ABTS and DPPH methods. RESULTS: Maesa lanceolata and Leucosidea sericea with an MIC of 0.02 mg/ml had excellent antibacterial activity against Enterococcus faecalis and Pseudomonas aeruginosa. There was a poor correlation between antioxidant activity and antibacterial activity with R2 = 0.143. This is because antibacterial activity is mainly related to non-polar compounds and antioxidant activity to polar compounds. Maesa lanceolata extracts had a low cytotoxicity with a selectivity index of 5.2, 2.6, 2.6 and 1.3 for P. aeruginosa, E. faecalis, E. coli and S. aureus respectively. Strychnos mitis extracts had a therapeutic index of 1.1 for E. coli. CONCLUSIONS: This study shows that plant extracts of some species used in ethnoveterinary medicine as anthelmintic may also have excellent antibacterial activity.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/metabolism , Helminthiasis, Animal/drug therapy , Plant Extracts/pharmacology , Plant Leaves/chemistry , Veterinary Drugs , Animals , Bacteria/drug effects , Ethnobotany , Medicine, Traditional , Microbial Sensitivity Tests , Plant Extracts/chemistry , South AfricaABSTRACT
Garlic, Allium sativum L., extract administered as a therapeutic bath was shown to have antiparasitic properties towards Neobenedenia sp. (MacCallum) (Platyhelminthes: Monogenea) infecting farmed barramundi, Lates calcarifer (Bloch). The effect of garlic extract (active component allicin) immersion on Neobenedenia sp. egg development, hatching success, oncomiracidia (larvae) longevity, infection success and juvenile Neobenedenia survival was examined and compared with freshwater and formalin immersion. Garlic extract was found to significantly impede hatching success (5% ± 5%) and oncomiracidia longevity (<2 h) at allicin concentrations of 15.2 µL L(-1) , while eggs in the seawater control had >95% hatching success and mean oncomiracidia longevity of 37 ± 3 h. At much lower allicin concentrations (0.76 and 1.52 µL L(-1)), garlic extract also significantly reduced Neobenedenia infection success of L. calcarifer to 25% ± 4% and 11% ± 4%, respectively, compared with 55% ± 7% in the seawater control. Juvenile Neobenedenia attached to host fish proved to be highly resistant to allicin with 96% surviving 1-h immersion in 10 mL L(-1) (15.2 µL L(-1) allicin) of garlic extract. Allicin-containing garlic extracts show potential for development as a therapy to manage monogenean infections in intensive aquaculture with the greatest impact at the egg and larval stages.
Subject(s)
Bass , Ectoparasitic Infestations/drug therapy , Fish Diseases/drug therapy , Fisheries/methods , Helminthiasis, Animal/drug therapy , Platyhelminths/drug effects , Sulfinic Acids/therapeutic use , Animals , Disulfides , Garlic/chemistry , Immersion , Ovum/drug effects , Phytotherapy/veterinary , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Platyhelminths/growth & developmentABSTRACT
The present study was designated to ascertain the anthelmintic activity of the rhizomes of Paris polyphylla and to isolate and characterize the active constituents. The methanol extract from rhizomes of P. polyphylla showed signiï¬cant anthelmintic activity against Dactylogyrus intermedius with the median effective concentration (EC50) 22.5 mg L(-1). Based on this finding, the methanol extract was fractionated by silica gel column chromatography in a bioassay-guided fractionation yielding 2 bioactive compounds, the structures of these compounds were elucidated as formosanin C and polyphyllin VII. The in vivo tests revealed that formosanin C and polyphyllin VII were significantly effective against D. intermedius with EC50 values of 0.6 and 1.2 mg L(-1), respectively. The acute toxicities (LC50) of formosanin C and polyphyllin VII for grass carp were 2.8 and 2.9 mg L(-1), respectively. The overall results provide important information for the potential application of formosanin C and polyphyllin VII in the therapy of serious infection caused by D. intermedius.
Subject(s)
Anthelmintics/pharmacology , Diosgenin/analogs & derivatives , Fish Diseases/drug therapy , Helminthiasis, Animal/drug therapy , Magnoliopsida/chemistry , Platyhelminths/drug effects , Saponins/pharmacology , Animals , Anthelmintics/chemistry , Anthelmintics/isolation & purification , Anthelmintics/toxicity , Aquaculture , Biological Assay/veterinary , Carps , Diosgenin/chemistry , Diosgenin/isolation & purification , Diosgenin/pharmacology , Diosgenin/toxicity , Fish Diseases/parasitology , Helminthiasis, Animal/parasitology , Medicine, Chinese Traditional , Methanol/chemistry , Parasitic Sensitivity Tests/veterinary , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Rhizome/chemistry , Saponins/adverse effects , Saponins/chemistry , Saponins/isolation & purification , Saponins/toxicityABSTRACT
Aqueous extracts from common tropical seaweeds were evaluated for their effect on the life cycle of the commercially important ectoparasite, Neobenedenia sp. (Platyhelminthes: Monogenea), through the survival of attached adult parasites, period of embryonic development, hatching success and oncomiracidia (larvae) infection success. There was no significant effect of any extract on the survival of adult parasites attached to fish hosts or infection success by oncomiracidia. However, the extracts of two seaweeds, Ulva sp. and Asparagopsis taxiformis, delayed embryonic development and inhibited egg hatching. The extract of A. taxiformis was most effective, inhibiting embryonic development of Neobenedenia sp. and reducing hatching success to 3% compared with 99% for the seawater control. Furthermore, of the 3% of eggs that hatched, time to first and last hatch was delayed (days 14 and 18) compared with the seawater control (days 5 and 7). Asparagopsis taxiformis shows the most potential for development as a natural treatment to manage monogenean infections in intensive aquaculture with the greatest impact at the embryo stage.
Subject(s)
Ectoparasitic Infestations/veterinary , Fish Diseases/drug therapy , Helminthiasis, Animal/drug therapy , Plant Extracts/pharmacology , Platyhelminths , Seaweed/chemistry , Animals , Aquaculture , Ectoparasitic Infestations/drug therapy , Fish Diseases/parasitology , Helminthiasis, Animal/parasitology , Ovum/drug effects , Perciformes , Plant Extracts/chemistryABSTRACT
BACKGROUND: Verbascum thapsus is used in tribal medicine as an antispasmodic, anti-tubercular agent and wormicide. In this study, we investigated the antispasmodic and anthelmintic activities of crude aqueous methanolic extract of the plant. METHODS: V. thapsus extracts were tested against roundworms (Ascaridia galli) and tapeworms (Raillietina spiralis). Each species of worm was placed into a negative control group, an albendazole treatment group, or a V. thapsus treatment group, and the time taken for paralysis and death was determined. In addition, relaxation activity tests were performed on sections of rabbit's jejunum. Plant extracts were tested on KCl-induced contractions and the relaxation activities were quantified against atropine. V. thapsus calcium chloride curves were constructed to investigate the mode of action of the plant extracts. RESULTS: We detected flavonoids, saponins, tannins, terpenoids, glycosides, carbohydrates, proteins, fats and fixed oils in V. thapsus. For both species of worm, paralysis occurred fastest at the highest concentration of extract. The relative index values for paralysis in A. galli were 4.58, 3.41 and 2.08, at concentrations of 10, 20 and 40 mg/ml of plant extract, respectively. The relative index for death in A. galli suggested that V. thapsus extract is wormicidal at high concentration. Similarly, the relative indexes for paralysis and death in R. spiralis suggested that the extract is a more potent wormicidal agent than albendazole. The mean EC(50) relaxation activity values for spontaneous and KCl induced contractions were 7.5 ± 1.4 mg/ml (6.57-8.01, n = 6) and 7.9 ± 0.41 mg/ml (7.44-8.46, n = 6), respectively. The relaxation activity of the extract was 11.42 ± 2, 17.0 ± 3, 28.5 ± 4, and 128.0 ± 7% of the maximum observed for atropine at corresponding concentrations. The calcium chloride curves showed that V. thapsus extracts (3 mg/ml), had a mean EC(50) (log molar [calcium]) value of -1.9 ± 0.06 (-1.87 - -1.98, n = 6) vs. control EC(50) = -2.5 ± 0.12 (-2.37 - -2.56, n = 6), whereas the verapamil (0.1 µM) EC(50) was -1.7 ± 0.1 (-1.6 - -1.8, n = 6) vs. control EC(50) = -2.4 ± 0.09 (-2.3 - -2.47, n = 5). CONCLUSIONS: Our results suggest that V. thapsus, which is currently used by some tribes in the Malakand region of Pakistan, has anthelmintic and antispasmodic value.
Subject(s)
Anthelmintics/pharmacology , Helminthiasis, Animal/drug therapy , Helminths/drug effects , Muscle Contraction/drug effects , Parasympatholytics/pharmacology , Plant Extracts/pharmacology , Verbascum , Albendazole/pharmacology , Animals , Ascaridia/drug effects , Atropine/pharmacology , Cestoda/drug effects , Helminthiasis, Animal/complications , Helminthiasis, Animal/mortality , Jejunum/drug effects , Muscle, Smooth/drug effects , Paralysis/etiology , Paralysis/prevention & control , Potassium Chloride , Rabbits , Spasm/chemically induced , Spasm/drug therapy , Vasodilator Agents/pharmacology , Verapamil/pharmacologyABSTRACT
BACKGROUND: Few drugs are available for soil-transmitted helminthiasis (STH); the benzimidazoles albendazole and mebendazole are the only drugs being used for preventive chemotherapy as they can be given in one single dose with no weight adjustment. While generally safe and effective in reducing intensity of infection, they are contra-indicated in first-trimester pregnancy and have suboptimal efficacy against Trichuris trichiura. In addition, drug resistance is a threat. It is therefore important to find alternatives. METHODOLOGY: We searched the literature and the animal health marketed products and pipeline for potential drug development candidates. Recently registered veterinary products offer advantages in that they have undergone extensive and rigorous animal testing, thus reducing the risk, cost and time to approval for human trials. For selected compounds, we retrieved and summarised publicly available information (through US Freedom of Information (FoI) statements, European Public Assessment Reports (EPAR) and published literature). Concomitantly, we developed a target product profile (TPP) against which the products were compared. PRINCIPAL FINDINGS: The paper summarizes the general findings including various classes of compounds, and more specific information on two veterinary anthelmintics (monepantel, emodepside) and nitazoxanide, an antiprotozoal drug, compiled from the EMA EPAR and FDA registration files. CONCLUSIONS/SIGNIFICANCE: Few of the compounds already approved for use in human or animal medicine qualify for development track decision. Fast-tracking to approval for human studies may be possible for veterinary compounds like emodepside and monepantel, but additional information remains to be acquired before an informed decision can be made.
Subject(s)
Anthelmintics/pharmacology , Drug Evaluation, Preclinical/methods , Helminthiasis, Animal/drug therapy , Helminthiasis/drug therapy , Aminoacetonitrile/analogs & derivatives , Aminoacetonitrile/pharmacology , Aminoacetonitrile/therapeutic use , Animals , Anthelmintics/therapeutic use , Depsipeptides/pharmacology , Depsipeptides/therapeutic use , Drug Approval , Europe , Humans , Nitro Compounds , Thiazoles/pharmacology , Thiazoles/therapeutic use , United StatesABSTRACT
In the present study, chloroform, aqueous, (polyethylene glycol/propylene carbonate) PEG/PC extracts were made from coconut, onion, garlic, fig, date tree, chicory, ananas, and cistrose. These extracts were tested in vivo and in vitro on their anthelmintic activity against cestodes (Hymenolepis diminuta, H. microstoma, Taenia taeniaeformis) and trematodes (Fasciola hepatica, Echinostoma caproni). In all in vitro tests, the target parasites died. It turned out that the treatment of mice and rats with a combination of onion and coconut extracts (with PEG/PC) eliminated all cestodes from their final hosts. In addition, the same composition was effective against the intestinal fluke E. caproni, but not against the liver fluke F. hepatica in the final host, while both worms were killed in vitro. Inoculation of fluids of coconut eliminated T. taeniaeformis tapeworms from naturally infected cats. This goal was not reached with oil of cistrose.
Subject(s)
Anthelmintics/pharmacology , Cestoda/drug effects , Plant Extracts/pharmacology , Trematoda/drug effects , Animals , Anthelmintics/isolation & purification , Cat Diseases/drug therapy , Cats , Disease Models, Animal , Helminthiasis, Animal/drug therapy , Mice , Parasitic Sensitivity Tests , Plant Extracts/isolation & purification , Rats , Rodent Diseases/drug therapy , Survival Analysis , Treatment OutcomeABSTRACT
BACKGROUND: Helminth parasites cause untold morbidity and mortality to billions of people and livestock. Anthelmintic drugs are available but resistance is a problem in livestock parasites, and is a looming threat for human helminths. Testing the efficacy of available anthelmintic drugs and development of new drugs is hindered by the lack of objective high-throughput screening methods. Currently, drug effect is assessed by observing motility or development of parasites using laborious, subjective, low-throughput methods. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a novel application for a real-time cell monitoring device (xCELLigence) that can simply and objectively assess anthelmintic effects by measuring parasite motility in real time in a fully automated high-throughput fashion. We quantitatively assessed motility and determined real time IC(50) values of different anthelmintic drugs against several developmental stages of major helminth pathogens of humans and livestock, including larval Haemonchus contortus and Strongyloides ratti, and adult hookworms and blood flukes. The assay enabled quantification of the onset of egg hatching in real time, and the impact of drugs on hatch rate, as well as discriminating between the effects of drugs on motility of drug-susceptible and -resistant isolates of H. contortus. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that this technique will be suitable for discovery and development of new anthelmintic drugs as well as for detection of phenotypic resistance to existing drugs for the majority of helminths and other pathogens where motility is a measure of pathogen viability. The method is also amenable to use for other purposes where motility is assessed, such as gene silencing or antibody-mediated killing.
Subject(s)
Anthelmintics/pharmacology , Drug Evaluation, Preclinical/methods , Helminthiasis, Animal/drug therapy , Helminthiasis/drug therapy , High-Throughput Screening Assays/methods , Animals , Anthelmintics/analysis , Dog Diseases/drug therapy , Dog Diseases/parasitology , Dogs , Drug Resistance , Helminthiasis/parasitology , Helminthiasis, Animal/parasitology , Helminths/drug effects , Helminths/physiology , Humans , Mice , Parasitic Sensitivity Tests , Sheep , Sheep Diseases/drug therapy , Sheep Diseases/parasitologyABSTRACT
CONTEXT: Trichosanthes dioica Roxb. (Cucurbitaceae), called pointed gourd in English, is a dioecious climber and its roots are traditionally used in India as a hydrogouge cathartic, tonic, and febrifuge, and in the treatment of jaundice, anasarca, and ascites. OBJECTIVE: To evaluate the in vitro effects of different solvent extracts of T. dioica root in experimental worms, viz. annelids and nematodes. MATERIALS AND METHODS: The in vitro paralytic and lethal effects of defatted dichloromethane (DCTD), methanol (METD), and aqueous (AQTD) extracts of T. dioica root were evaluated against Pheretima posthuma (Annelida) and Ascaridia galli (Nematoda) by keeping the worms in different concentrations of each test extract under specific experimental conditions followed by determination of mean paralysis and lethal times. Albendazole was used as the reference drug. RESULTS AND DISCUSSION: All the extracts demonstrated concentration-dependent paralytic and lethal effects on P. posthuma and lethal effects on A. galli. The DCTD was found to be the most potent followed by the METD and AQTD. A. galli was found to be more sensitive than P. posthuma against all extracts, indicating T. dioica root as an effective nematocide. CONCLUSION: The present study establishes the in vitro wormicidal property of T. dioica root extracts against the experimental worms, showing promising nematocidal (and hence anthelmintic) potential.
Subject(s)
Anthelmintics/pharmacology , Antinematodal Agents/pharmacology , Ascaridia/drug effects , Oligochaeta/drug effects , Paralysis/chemically induced , Plant Extracts/pharmacology , Trichosanthes/chemistry , Animals , Anthelmintics/administration & dosage , Antinematodal Agents/administration & dosage , Ascaridia/isolation & purification , Chickens/microbiology , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Helminthiasis/drug therapy , Helminthiasis, Animal/drug therapy , Helminthiasis, Animal/parasitology , Intestinal Diseases, Parasitic/drug therapy , Phytotherapy , Plant Extracts/administration & dosage , Plant Roots/chemistry , Solvents , Time FactorsABSTRACT
Conventional drugs have become expensive and therefore unaffordable to resource-limited farmers, causing farmers to seek low cost alternatives, such as use of medicinal plants. In this study, a survey was conducted in order to document information on medicinal plants used by farmers in the control of internal parasites in goats in the Eastern Cape Province. Structured questionnaires and general conversation were used to collect the information from farmers and herbalists. The survey revealed 28 plant species from 20 families that are commonly used in the treatment of gastro-intestinal parasites in goats. The plant family Asphodelaceae was frequent in usage, comprising 21.4% of the plants, and the Aloe was the most utilized species (50%). Leaves were the most frequently used plant parts (45.9%), and decoctions constituted the majority of medicinal preparations (70%). Medicinal plants are generally used in combination with other plants, and/or non-plant substances, but a few plants are used on their own. These medicinal plant remedies are administered orally, mainly by use of bottles and this is done twice in summer at intervals of one month, only once in winter and when need arises thereafter. Some of the mentioned plants have been reported in literature to possess anthelmintic properties, while others possess activities ranging from anti-inflammatory, analgesic, antimicrobial, purgative, anti-edema to immuno-regulation. If their safety and efficacy could be confirmed, these plants could form an alternative cost effective strategy in managing helminthiasis in the province.
Subject(s)
Anthelmintics/pharmacology , Helminthiasis, Animal/drug therapy , Phytotherapy/veterinary , Plants, Medicinal/chemistry , Adult , Animals , Data Collection , Ethnobotany , Ethnopharmacology , Gastrointestinal Diseases/drug therapy , Gastrointestinal Diseases/parasitology , Gastrointestinal Diseases/veterinary , Goats , Helminthiasis, Animal/parasitology , Humans , Medicine, African Traditional , Middle Aged , South AfricaABSTRACT
Atualmente, o estudo da atividade anti-helmíntica de plantas medicinais em ruminantes tem atraído bastante interesse. Mentha villosa Huds. (Lamiaceae) é uma das espécies de hortelã que tem sido utilizada popularmente devido às diversas propriedades medicinais, inclusive para o controle de verminoses. O presente estudo teve como objetivo testar a atividade anti-helmíntica do hidrolato dessa planta em bezerras infectadas por nematóides gastrintestinais, tanto in vitro, pelo método de coprocultura quantitativa, quanto in vivo, por meio do teste de redução no número de ovos de nematóides nas fezes dos hospedeiros. No teste in vitro, o hidrolato nas concentrações de 40 por cento, 60 por cento e 80 por cento e 100 por cento apresentou porcentagem de eficácia de 91,88 por cento, 94,15 por cento, 98,40 por cento e 100 por cento, respectivamente, mostrando atividade ovicida significativa sobre nematóides gastrintestinais em bezerras. Entretanto, os resultados do teste in vivo mostraram ausência de atividade anti-helmíntica do hidrolato de M. villosa na dose de 0,1ml kg dia-1, nos animais tratados.
Currently, it has been of great interest to study the anthelmintic activity of medicinal plants in ruminants. Mentha villosa Huds. (Lamiaceae) is one of the mint species that has been popularly used based on various medicinal properties, even for the control of nematode infections. This study aimed to test the anthelmintic activity of hidrolact of this plant, both in vitro, by the quantitative coproculture method, and in vivo, in calves infected with gastrointestinal nematodes, through the egg count reduction test in feces of the hosts. In in vitro tests, the hidrolact at the concentrations 40 percent, 60 percent and 80 percent and 100 percent obtained percentage of effectiveness of 91.88 percent, 94.15 percent, 98.40 percent and 100 percent respectively, showing significant ovicidal activity against gastrointestinal nematodes in calves. However, the hidrolact of M. villosa showed no in vivo anthelmintic activity at 0.1ml kg-1 day-1 on the treated animals.