Egg Hatching Inhibition Research Articles

In vitro anthelmintic and cytotoxic activities of extracts of Persea willdenovii Kosterm (Lauraceae).

This study describes the effects of extracts and fractions of Persea willdenovii leaves against goat gastrointestinal nematodes and their cytotoxicity on Vero cells. The in vitro ovicidal and larvicidal activities of the crude ethanolic, hexane, ethyl acetate (EAE), butanolic and residual hydroethanolic extracts were assessed through the inhibition of egg hatching and larval motility assays. The most active extract (EAE) was then fractionated by chromatography in an open column containing silica gel, to furnish six fractions (Fr1-Fr6), which were also tested. The cytotoxicity of active extracts and fractions was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and trypan blue exclusion assay. The EAE and two fractions (Fr1 and Fr2) showed inhibitory activity in the egg hatching of gastrointestinal nematodes of goats in a concentration-dependent manner. The effective concentrations for 50% inhibition (EC50) of egg hatching were 2.3, 0.12 and 2.94 mg/ml for EAE, Fr1 and Fr2, respectively. All extracts and fractions were not effective in inhibiting 50% of motility of infective larvae. EAE and Fr2 had IC50 values (50% inhibitory concentration) of 4.95 and 2.66 mg/ml, respectively. Fr1 showed a slight cytotoxic effect (cellular inviability <30%) only after 48h of treatment (MTT test). Gas chromatography-mass spectrometry (GC-MS) analysis showed the presence of six fatty acid ethyl esters, a fatty acid methyl ester and a long-chain ketone in the most active fraction. These constituents identified in P. willdenovii can be related to the high ovicidal activity and relatively non-toxic effect of the extracts.

Lysiloma acapulcensis leaves contain anthelmintic metabolites that reduce the gastrointestinal nematode egg population in sheep faeces

One metabolite against lamb gastrointestinal nematodes (GIN) was identified from extracts of Lysiloma acapulcensis leaves. Firstly, an aqueous extract of L. acapulcensis leaves and two fractions, organic and aqueous, were evaluated at different concentrations against Haemonchus contortus eggs and histotrophic larvae. In other experiment, 35 Pelibuey GIN-infected lambs were randomly divided into five groups, as follows: (1) ivermectin (0.2 mg/kg BW); (2) control (untreated); (3) rutin (10 mg/kg BW, as a flavonoid comparison control); (4) L. acapulcensis leaves ethyl acetate fraction (EtAc-F, 25 mg/kg BW); and (5) L. acapulcensis leaves (dried and grinded, 5 g/kg BW). The EtAc-F fraction caused 94.8% egg-hatching inhibition (P < 0.05, 6.25 mg/ml). Likewise, at 50 mg/ml, this fraction resulted in 100% larval mortality. In the second experiment, the highest eggs per gram (EPG) of faeces reduction caused by ivermectin was 80.2% (ȳ = 61.8%); meanwhile, rutin showed a highest EPG reduction = 66.2% (ȳ = 37.5%). Similarly, EtAc-F fraction showed 62.9% EPG highest reduction (ȳ = 32.5%). On the other hand, lambs fed with L. acapulcensis leaves showed a maximum EPG reduction = 50.1% (ȳ = 29.4%). Chromatography analysis (HPLC; NRM) of EtAc-F fraction revealed the presence of myricitrin as a major compound. Lysiloma acapulcensis leaves EtAc-F exhibited the highest in vitro activity against H. contortus eggs and larvae. The low efficacy of ivermectin suggests the presence of anthelmintic resistance. Lysiloma acapulcensis leaves and fractions can be considered in future experiments searching for a sustainable alternative of GIN control.

In vitro anthelmintic and cytotoxicity activities the Digitaria insularis (Poaceae)

This study aimed to evaluate the in vitro activity of D. insularis extracts and fractions against gastrointestinal nematodes of goats and its cytotoxicity on Vero cells. The egg hatch (EHT) and larval motility (LMT) tests were conducted to investigate the anthelmintic effects of the crude hydroethanolic (CH), ethyl acetate (EA), butanolic (BT) and residual hydroethanolic (RH) extracts. The elution of the active extract (EA) on column chromatography (SiO2) using organic solvents furnished six fractions (FR1 to FR6), which were also tested. Cytotoxicity was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Trypan Blue exclusion assays. All extracts, FR2 and FR3, inhibited egg hatching in a concentration-dependent manner. The EHT led to EC50 values (effective concentration 50%) of 0.64; 0.69; 0.77; 0.96; 0.27 and 0.65mg/mL for CH, EA, BT, RH, FR2 and FR3, respectively. However, the extracts exhibited low effect on the motility of L3. In the cytotoxicity evaluation (MTT assay), the IC50 (inhibitory concentration 50%) was 1.18 (EA), 1.65 (FR2) and 1.59mg/mL (FR3), which was relatively high (low toxicity) in comparison to the EC50 values in EHT, mainly for FR2. The chemical analyses of most active fractions (FR2) by Liquid Chromatography coupled to Mass Spectrometry (LC–MS) led the characterization of the flavones tricin and diosmetin. These results showed the high anthelmintic effect and low cytotoxicity of D. insularis and also that the flavones can be probably responsible for the nematocidal activity of this plant.

The Edible Mushroom Pleurotus djamor Produces Metabolites with Lethal Activity Against the Parasitic Nematode Haemonchus contortus.

Pleurotus djamor is an edible mushroom that has medicinal properties. This study aimed to assess the in vitro activity of P. djamor extracts and fractions against Haemonchus contortus eggs and exsheathed infective larvae (L3). Crude hydroalcoholic extracts were obtained by maceration and fractions were obtained through chromatography. Metabolite identity was determined using gas chromatography/mass spectrometry (GC-MS) analysis. The results showed that P. djamor extracts had no significant activity against eggs at the concentrations used. However, the extract showed 98.7% and 77% larval mortality 72 h postconfrontation at 320 and at 160 mg/mL, respectively. The chromatography analysis resulted in 23 fractions that were eventually grouped into three fractions (E1, E2, and E3). These fractions showed the following egg hatching inhibition percentages: E1 = 100, E2 = 38.7, and E3 = 5.5 at 10 mg/mL concentration 72 h postexposure. Likewise, larval mortality percentages after this period were 90.6, 100, and 0.44 at 40 mg/mL (P < .05), respectively. The GC-MS showed five major compounds in E1 fraction, including four fatty acids: (i) pentadecanoic, (ii) hexadecanoic, (iii) octadecadienoic, (iv) octadecanoic acid, and one terpene identified as β-sitosterol. We concluded that the edible mushroom P. djamor possesses nematicidal metabolites, which could be used as an alternative anthelmintic treatment.

Insecticidal factors from the seeds of Erythrina indica Lam against Hyblaea puera, the most serious defoliator pest of teak

The organic solvent extracts from the seeds of Erythrina indica were tested for their insecticidal action against Hyblaea puera, the most important defoliator pest of teak. The larvicidal activity of the petroleum ether, chloroform, methanol, ethyl alcohol, ethyl acetate, acetone and water extracts from the seeds of E. indica on the 3rd instar larvae of H. puera showed 100% mortality even with least concentration (0.25%). The ovicidal activity was exhibited by chloroform and ethyl acetate extract. Both the extracts exhibited highest egg hatch inhibition (56%) at highest concentration (2%). The least LC50 (1.15%) shows that ethyl acetate extract is better than chloroform extract (1.78). Two compounds were isolated from the ethyl acetate extract of the seeds of Erythrina indica by column chromatography. The compounds were identified using HPLC, GC MS, and NMR. Compound 1 was a mixture of linoleic acid and oleic acid. Compound 2 was a mixture of linoleic acid and oleic acid ester with a glycerol unit attached to it. Compounds 1 and 2 were biologically active and exhibited potent insecticidal activity against the 3rd instar larvae of H. puera. The result showed that Compound 2 isolated from E. indica exhibited highest mortality (72%) at concentration (0.125%). At highest concentration (0.5%) highest mortality (92%) was exhibited by Compound 2 which on comparison is on par with the Neemark (Azadirachtin) exhibiting highest mortality (100%). The study is complementary with earliar works and proves that the seeds of E. indica has immense potential to be utilized as botanical insecticide.

Anthelmintic effect of biofabricated silver nanoparticles using Ziziphus jujuba leaf extract on nutritional status of Haemonchus contortus

The present work was aimed to evaluate the efficacy of biofabricated silver nanoparticles (AgNPs) synthesized by using the aqueous extract of Ziziphus jujuba leaves against a small ruminant gastrointestinal nematode, Haemonchus contortus. AgNPs characterization was done through UV–vis spectral analysis, scanning and transmission electron microscopy and X-ray diffraction study, indicating synthesis of spherical and extremely small (28–44nm) nanoparticles. In vitro anthelmintic assay was based on egg hatch assay (EHA) and adulticidal study. The highest concentration of AgNPs induced 91±1.76 percent egg hatch inhibition. IC50 and IC90 values for EHA were 0.007ppm and 7.71ppm following AgNPs treatment and 301.83ppm and 849.43ppm with Z. jujuba aqueous leaf extract. In vitro adulticidal assay showed LC50 and LC90 values to be 15.29ppm and 33.87ppm with AgNPs while 942.68ppm and 2047.50ppm following exposure with Z. jujuba leaf extract. Distinct alterations were also noticed in egg morphology. Moreover, nutritional status of H. contortus was greatly influenced by AgNPs treatments as evident from significantly (P<0.05) reduced levels of glycogen, lipid and proteins depicting 5.69–21.81% depletion in adult worms. To our knowledge these results depict for the first time that Z. Jujuba possesses anthelmintic as well as reducing properties for AgNPs synthesis which altered nutritional parameters thus could serve as a candidate anthelmintic agent for controlling life threatening H. contortus infections in small ruminants.

Anthelmintic effects of forage chicory (Cichorium intybus) against free-living and parasitic stages of Cooperia oncophora

Chicory shows great promise as an anthelmintic forage for grazing ruminants that can reduce reliance on anti-parasitic drugs. Recently, we reported potent anthelmintic effects of chicory-based diets in infected cattle with significant reductions in worm burdens of the abomasal nematode Ostertagia ostertagi, whilst no apparent activity was observed against the small intestinal parasite Cooperia oncophora. To explore this discrepancy, we investigated direct anthelmintic effects of forage chicory against C. oncophora in vitro. Chicory leaves (cultivar ‘Spadona’) were extracted with methanol in a Soxhlet apparatus and the resulting extract was purified by solid-phase extraction to concentrate bioactive phytochemicals such as sesquiterpene lactones. C. oncophora eggs and adult worms from mono-infected donor calves were exposed to decreasing concentrations of the chicory extract. In an egg hatch assay, the chicory extract induced a marked and dose-dependent inhibition of egg hatching, with 95% inhibition at 2500μg extract/mL (EC50=619 [95% CI: 530–722] μg extract/mL). In the adult motility inhibition assays, the chicory extract induced a potent and dose-dependent worm paralysis. At 12h of incubation, worms exposed to chicory showed a total paralysis at ≥500μg extract/mL, while after 48h of incubation a complete inhibition of worm motility was observed at ≥250μg extract/mL (EC50=80 [95% CI: 67–95] μg extract/mL). We have demonstrated that forage chicory can induce potent inhibitory effects on the egg hatching and exert direct anthelmintic activity against parasitic stages of C. oncophora. These results suggest that the previously reported absence of in vivo effects of chicory towards C. oncophora in infected animals may be related with host-mediated factors and/or inhibitory digestive conditions, rather than an inherent inactivity of chicory and its bioactive phytochemicals.

Repellent, oviposition-deterrent and egg-hatching inhibitory effects of some plant essential oils against citrus mealybug, Planococcus citri Risso (Hemiptera: Pseudococcidae)

The citrus mealybug (Planococcus citri) is a serious pest of citrus groves in Turkey and has recently caused considerable damages to some cut flowers (especially, roses and orchids) in greenhouses in Antalya (southwestern Turkey). In this study, repellent and oviposition-deterrent activities of essential oils from anise (Pimpinella anisum), rosemary (Rosmarinus officinalis), peppermint (Mentha piperita), Turkish oregano (Origanum onites) and thyme (Thymus vulgaris) were investigated against female adults of P. citri under laboratory conditions. The results from the study showed that all the essential oils tested had a repellent activity in varying degrees, and the repellency was concentration and time dependent. Based on the highest dose (5 mL/L water) and the longest time period after the insect introduction (96 h), the oils from O. onites and T. vulgaris had the highest percent repellency in both choice and no-choice tests (O. onites: 88.9 and 65.4%; T. vulgaris: 88.8 and 69.6%, respectively), and followed by P. anisum (80.1 and 50%) and R. officinalis (57.1 and 45.2%) oils. In the oviposition deterrency assays using the highest concentration (5 mL/L water), O. onites essential oil showed the most potent oviposition deterrency (63.7%) resulting in the lowest mean number of eggs laid by the mealybug females (48.8 eggs per female) followed by P. anisum (56.9%). Furthermore, these two oils had the most potent egg-hatching inhibitory effects and inhibited egg hatching by 59.2 and 46.8%, respectively. Overall results suggest that the essential oils tested may help for us in controlling P. citri populations in various agroecosystems.

Potential of Inula racemosa root extract and its fractions to suppress root-knot nematode Meloidogyne incognita

Nematicidal potential of chloroform root extract of Inula racemosa and its fractions was investigated on egg hatching and mortality of root knot nematode Meloidogyne incognita. Egg masses and second stage juveniles (J2) of M. incognita were exposed to different concentrations (0.1-8.0 mg ml-1) of I. racemosa root extract and its fractions. Observations on egg hatch were recorded on 1st, 3rd, 5th, 7th and 9th day and those of mortality studies were recorded on 2nd, 4th, 6th, 8th and 10th day, respectively. Significant mortality as well as egg hatch inhibition was observed for all the tested components at 5 %. The root extract was found to be most effective in controlling egg hatching as complete inhibition was observed at 8.0 mg ml-1 concentration on 1stday of treatment and nonpolar fraction was most effective in causing mortality of J2 of M. incognita as 100 % inhibition was observed at 6.0 and 8.0 mg ml-1 concentration on 2nd day of treatment. Maximum inhibition of egg hatching was observed for root extract at 8.0 mg ml-1 concentration and 100 % mortality was observed for root extract as well as nonpolar fraction at the same concentration. The nonpolar fraction was most effective in causing mortality as maximum mortality was observed at 6.0 and 8.0 mg ml-1 concentration throughout the exposure time. Polar fraction was least effective among all the components both in egg hatch inhibition and J2 mortality of M. incognita. Both the activities showed concentrations as well as time dependence. Results show different role of tested components on egg hatching and mortality of root knot nematode. The root extract of I. racemosa and its fractions showed a potential to develop new nematicide.

Invitro assessment of Argemone mexicana, Taraxacum officinale, Ruta chalepensis and Tagetes filifolia against Haemonchus contortus nematode eggs and infective (L3) larvae.

Argemone mexicana, Taraxacum officinale, Ruta chalepensis and Tagetes filifolia are plants with deworming potential. The purpose of this study was to evaluate methanolic extracts of aerial parts of these plants against Haemonchus contortus eggs and infective larvae (L3) and identify compounds responsible for the anthelmintic activity. Invitro probes were performed to identify the anthelmintic activity of plant extracts: egg hatching inhibition (EHI) and larvae mortality. Open column Chromatography was used to bio-guided fractionation of the extract, which shows the best anthelmintic effect. The lethal concentration to inhibit 50% of H.contortus egg hatching or larvae mortality (LC50) was calculated using a Probit analysis. Bio-guided procedure led to the recognition of an active fraction (TF11) mainly composed by 1) quercetagitrin, 2) methyl chlorogenate and chlorogenic acid. Quercetagitrin (1) and methyl chlorogenate (2) did not show an important EHI activity (3-14%) (p<0.05); however, chlorogenic acid (3) showed 100% of EHI (LC50 248μg/mL) (p<0.05). Chlorogenic acid is responsible of the ovicidal activity and it seems that, this compound is reported for the first time with anthelmintic activity against a parasite of importance in sheep industry.

Anthelmintic activity of Tunisian chamomile (Matricaria recutita L.) against Haemonchus contortus

The chemical treatment of gastrointestinal parasitic diseases has been undermined by increasing resistance and high toxicity. There is an urgent need to search for alternative natural sources for the treatment of such parasites. In this respect, the present study aims to quantify phenolic compounds of chamomile (Matricaria recutita L.) and to study their in vitro anti-oxidant and anthelmintic activities in solvents with increasing polarity. In vitro determination of anti-oxidant capacity was carried out using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation methods. In vitro anthelmintic activity was investigated on egg-hatching inhibition and loss of motility of adult worms of Haemonchus contortus from sheep. The results showed that methanolic and aqueous extracts contain more total polyphenols, total flavonoids and condensed tannins than chloroformic and hexanic extracts. ABTS and DPPH assays showed that methanolic extracts had the highest anti-oxidant potency (IC50 = 1.19 μg/ml and 1.18 μg/ml, respectively). In vitro anthelmintic activity showed that both methanolic (IC50 = 1.559 mg/ml) and aqueous (IC50 = 2.559 mg/ml) extracts had the greatest effect on egg hatching and motility of worms (100% after 8 h post exposure at 8 mg/ml). A significant and positive correlation between DPPH and ABTS tests was observed for all tested extracts. Therefore, total phenolic, total flavonoid and condensed tannin values were correlated with IC50 from both ABTS and DPPH, and with inhibition of egg hatching. To our knowledge, this report is the first of its kind to deal with in vitro anthelmintic activities of chamomile extracts.

Caffeoyl and coumaroyl derivatives from Acacia cochliacantha exhibit ovicidal activity against Haemonchus contortus

Ethnopharmacology relevanceAcacia cochliacantha is a small tree whose foliage is traditionally used in Mexico for treatment of kidney pain, gastrointestinal illnesses and to kill intestinal parasites. In recent decades, the study of vegetal extracts has offered other possible alternatives for the control of Haemonchus contortus. Considering that this nematode affects dramatically the health and productivity of small ruminants, the aim of this study was to identify the anthelmintic compounds from A. cochliacantha hydro-alcoholic extract (HA-E) through an ovicidal test. Material and methodsIn vitro egg hatch assay was conducted to determinate the anthelmintic effects of a HA-E (60g). Liquid-liquid ethyl acetate/water extraction gave two fractions (EtOAc-F, 1.92g; Aq-F; 58.1g). The less polar compounds from ethyl acetate fraction were extracted by addition of dichloromethane offering a precipitate phase (Mt-F, 1.25g) and a soluble mixture (DCMt-F 1.15g). All fractions were evaluated for ovicidal activity obtaining the egg hatching inhibition (EHI, 0.07–25mg/mL). Ivermectin (0.5mg/mL) was used as a reference drug (positive control), and distilled water, 2.5% DMSO and 2% methanol were used as negative controls. The isolated compounds from the most active fractions were subjected to spectroscopic (1H NMR) Spectrometric (MS) and UV HPLC analysis in order to identify the bioactive compounds. ResultsThe less polar treatments (AcOEt-F, DCMt-F, DCMt-P) showed the highest ovicidal activities (98–100% EHI; at 0.62–1.56mg/mL) and the major compounds found in these fractions were identified as caffeoyl and coumaroyl derivatives, including caffeic acid (1), p-coumaric acid (2), ferulic acid (3), methyl caffeate (4), methyl-p-coumarate (5), methyl ferulate (6) and quercetin. In case of the less active fractions (Aq-F, Mt-F) were constituted principally by glycosylated flavonoids. ConclusionThese results show that caffeoyl and coumaroyl derivatives from Acacia cochliacantha leaves had promising anthelmintic activity against Haemonchus contortus. This leguminous may offer an alternative source for the control of gastrointestinal nematodes of small ruminants.

Anthelmintic activity of Moringa oleifera seed aqueous and ethanolic extracts against Haemonchus contortus eggs and third stage larvae

Haemonchus contortus is one of the prevalent and pathogenic ruminant parasites that has grown resistance to common anthelmintic treatment. This study evaluated the anthelmintic potential of Moringa oleifera seed ethanolic and aqueous extracts against H. contortus eggs and infective stage larvae (L3s). The efficacy of five extract concentrations (0.95, 1.95, 3.9, 7.8, and 15.6mg/mL) were tested through egg hatch assay and larval motility test. Phytochemical tests were conducted to detect the different plant secondary metabolites in the extracts. In the ovicidal assay, the ethanolic and aqueous extracts showed 95.89% and 81.72% egg hatch inhibition at 15.6mg/mL, respectively. The ovicidal activity of 15.6mg/mL ethanolic extract was comparable with that of albendazole (p>0.05). The LC50 against the eggs was recorded at 2.91 and 3.83mg/mL for ethanolic and aqueous extracts, respectively. In the larvicidal assay, the ethanolic and aqueous extracts exhibited 56.94% and 92.50% efficacy at 7.8mg/mL, respectively. The larvicidal activity of 7.8mg/mL aqueous extract was similar statistically with that of ivermectin (p>0.05). The LC50 against L3s was recorded at 6.96 and 4.12mg/mL for ethanolic and aqueous extracts, respectively. The secondary metabolites detected were tannins in ethanolic extract and saponins in aqueous extract. Both extracts inhibited larvae formation inside the eggs and rendered the L3s immobile. Therefore, M. oleifera seed extracts contained plant bioactive compounds with anthelmintic property against the eggs and L3s of H. contortus.

Anthelmintic evaluation of Cucurbita pepo againstgastrointestinal nematodes of sheep

The study was aimed at to investigate the anthelmintic efficacy of aqueous and ethanolic extracts of Cucurbita pepo against gastrointestinal nematodes of sheep by scientifically validated in vitro and in vivo tests. In vitro anthelmintic activity was determined by egg hatch assay, larval migration inhibition assay and larval development assay against eggs and larvae of mixed gastrointestinal nematodes of sheep. The extracts which were found to be effective in in vitro assays were further evaluated by in vivo faecal egg count reduction test against mixed species of sheep gastrointestinal nematodes with 3 different doses (125, 250 and 500 mg kg-1). Haematological and serum parameters were estimated before and after treatment to determine the impact of plant extracts on health of the animal. Aqueous extract of C. pepo demonstrated significant inhibition of egg hatch at 40 and 80 mg/ml. The ED50 value of egg hatch inhibition was 3.51mg/ml. In larval migration inhibition assay, both aqueous and ethanolic extracts of C. pepo demonstrated inhibition of larval migration and the LM50 was 1.75 and 0.32 mg/ml respectively. However, in larval development assay, both aqueous and ethanolic extracts showed only marginal inhibition of larval development at all concentrations tested. In faecal egg count reduction test (FECRT), aqueous extracts of C. pepo at 500 mg/kg caused significant reduction in eggs per gram (96.61 per cent) the reduction being higher than the result obtained with albendazole, the positive control (93.25 per cent). There was a significant difference in EPG reduction between sheep treated with albendazole and C. pepo. Haematological and serum parameters were not affected in both the treated and untreated sheep indicating that the extracts did not cause toxic effects. Based on the results obtained in this study, the aqueous extract of C. pepo possesses anthelmintic activity and could offer an alternative source for the control of gastrointestinal nematodes of sheep.

Control of Haemonchus contortus in sheep using basidiocarps of Agaricus blazei Murril.

This study evaluated the effects in vitro and in vivo of Agaricus blazei against Haemonchus contortus in sheep. The in vitro efficacy of aqueous extract on egg hatching inhibition (EHI) was investigated and after 72h incubation with varying concentrations the effects on, blastomeres, embryonated eggs, and first stage larvae (L1) were evaluated. Larval development inhibition (LDI) for dry powder and the aqueous extract were evaluated in fecal cultures of sheep infected with H. contortus. In vivo efficacy was determined by reduction in fecal egg count (FEC). Lambs were treated with powder A. blazei (11.4g/kg pc) or trichlorfon, or were untreated and the possible toxicity of this fungus was monitored by plasmatic enzyme analysis. Concentrations equal to and higher than 3.62mg/mL and of aqueous extract were 100% effective in the EHI test. In the LDI test, LC90 was estimated for 5.66 and 106.0mg/g fecal culture for aqueous extract and powder, respectively. The mean FEC in lambs 14days post-treatment with A. blazei powder was significantly lower than observed for the negative control, and the serum levels of aspartate transaminase and alanine transaminase were normal. The fungi supplementation promotes, respectively, high and moderate anthelmintic efficacy with in vitro and in vivo tests, respectively, suggesting it as an alternative or complementary treatment for haemonchosis in sheep.

In Vitro Anthelmintic Activity of Crude Extracts of Aerial Parts of Cissus quadrangularis L. and Leaves of Schinus molle L. against Haemonchus contortus.

Background Haemonchus contortus, the causative agent of Haemonchosis, is the most economically important parasite in small ruminant production. Control with chemotherapy has not been successful due to rapid emergence of drug-resistant strains. There is a continuous search for alternative leads particularly from plants. The study aimed to evaluate the anthelmintic activity of crude methanolic extracts of leaves of Schinus molle and aerial parts of Cissus quadrangularis against H. contortus. Methods. Adult motility test and egg hatching inhibition assay were employed to investigate the in vitro adulticidal and egg hatching inhibitory effects of the extracts. Results Higher concentrations of the extracts (10 and 5 mg/ml) had a significantly superior adulticidal activity (p < 0.05) compared to the negative control and lower concentration levels, which was comparable to albendazole. Similarly, the relative egg hatch inhibition efficacy of S. molle and C. quadrangularis extracts indicated a maximum of 96% and 88% egg hatch inhibition, respectively, within the 48 hrs of exposure at 1 mg/ml. Conclusion The current study evidenced that the crude methanolic extracts of the plants have promising adulticidal and egg hatching inhibitory effects against H. contortus.

Ovicidal activity of succinic acid isolated from sisal waste (Agave sisalana) against gastrointestinal nematodes of goats

ABSTRACT: This study was conducted to evaluate the in vitro anthelmintic activity of the succinic acid (SA) isolated from sisal waste against gastrointestinal nematodes of goats, using the egg hatching and larvae motility assays. In addition, potential cytotoxicity of SA on Vero cell cultures was investigated by means of MTT (3-4,5-dimethylthiazol-2-yl, 2,5diphenyltetrazolium bromide) test. The SA induced a significant inhibition of egg hatching (P&lt;0.05) at all concentrations tested (60 to 250µg mL-1), and the concentrations to inhibit 50% (EC50) and 90% (EC90) values (mean ± standard deviation) were 90.3±2.8 and 130.6±3.5µg mL-1, respectively. The SA has not shown larvicidal activity. The SA was less toxic to the Vero cells, with the mean percentage of cell viability equal to 85±6.2% at the concentration of 130µg mL-1. The results suggested that SA has potential anthelmintic effect; although, more research is needed to confirm its activity in vivo.

Pancreatic lipase-related protein 2 is essential for egg hatching in the brown planthopper, Nilaparvata lugens.

In this study, we identified a pancreatic lipase-related protein 2 (PLRP2) gene through searching the transcriptome data of the brown planthopper, Nilaparvata lugens, a monophagous rice pest. PLRP2 mRNAs were first isolated in the human pancreas and play an important role in hydrolysis of galactolipids from the diet. Although homologous PLRP2 genes have been identified in many insect species, their physiological functions remain unknown. The present study for the first time reports the functional role of PLRP2 in an insect species. Differing from mammal PLRP2s, N. lugens PLRP2 was highly expressed in developing oocytes of the ovaries of female adults and little expressed in laid eggs. Suppression of N. lugens PLRP2 expression using RNA interference significantly inhibited egg hatching in rice seedlings, implying that N. lugens PLRP2 was important for oocyte maturation and development. This novel finding will improve our understanding of the reproductive strategies in insects and provides a potential target for future management of crop pests.

Susceptibilidad Diferencial a Spinosad en Huevo, Instares Larvales, Pupa, y Hembra deAedes aegypti(L.)

Abstract. Aedes aegypti may be considered the most dangerous animal to the human being due to the number and severity of the diseases it transmits. We evaluated the relative toxicity of spinosad against eggs, larvae, pupae, and females of the New Orleans strain of this species. Initially, we estimated the concentrations that caused between 0 and 100% mortality, and then intermediate concentrations that covered this range were included. Five replications were carried out and each replication included an untreated control. The percentage of egg hatching inhibition (eggs) and percentage mortality (larvae, pupa, and adult female) was recorded after 24 hours of exposure. The LC50 for eggs was 28.9 mg liter-1, the data modeled a straight line (R2 = 0.9747) and the highest percentage of egg hatching inhibition was 70%. The LC50 for each instar larvae was: 1 = 0.009 mg liter-1, 2 = 0.017 mg liter-1, 3 = 0.08 mg liter-1, and 4 = 0.12 mg liter-1. In the same order, the LC95 values were 0.064, 0.14, 0.28, and 0.62 m...

Oviposition Deterrence and Egg Hatch Inhibition of Fruit Fly, Bactrocera tau (Walker) by Some Plant Products, Bio-pesticides and Clay

Oviposition Deterrence and Egg Hatch Inhibition of Fruit Fly, Bactrocera tau (Walker) by Some Plant Products, Bio-pesticides and Clay