Preliminary Evaluation Of The Efficacy Of Melia Azedarach In The Control Of Haemonchus Contortus

Haemonchus contortus belongs to the genus Haemonchus in the family tricholomoideae.It lives on the ruminant stomach or small intestine of cattle,sheep,camels and other ruminants.It sucks the blood of the host for living,resulting in anemia emaciation and death of the host.which cause huge economic losses to animal husbandry every year.Melia azedarach Linn.has been used in the treatment of digestive tract parasitosis in ancient China for 2000 years.Its fruit,root,skin and stem can be used as medicine.It has the functions of removing dampness and pain,treating hernia,scabies and insect repellent,and widely distributed in the south of China.Melia azedarach is widely used in agriculture and forestry.It is famous for its insecticidal activity.However,the efficacy of Melia azedarach against Haemonchus contortus is still unclear.Purposes:In order to find out the effect of Melia azedarach against Haemonchus contortus,this project select the best Melia azedarach extract by observing the effect of how Melia azedarach extract will effect the activity and morphological of eggs and larvae stage of Haemonchus contortus,we implement experiments in vivo to detect the reduction rate of eggs and the changes of physiological indexes of sheep before and after the application of the medicine,and preliminarily evaluat the driving effect of Melia azedarach on Haemonchus contortus,with a view to serving as domestic animals to prevention and control of onychomycosis and the research and development of plant insecticides lay the foundation.Methods:(1)The eggs were collected by saturated salt water floating method,observed and counted under the microscope;the IL3 of Haemonchus contortus were collected by Berman funnel method,observed and counted under the microscope;the Melia azedarach was extracted by solution extraction and ultrasonic assisted method,and the crude Melia azedarach was obtained by freeze-drying after rotation evaporation.(2)In vitro anthelmintic test: five concentrations of water extract and ethanol extract of Melia azedarach were set for egg hatching test and larva activity test.48 hours after the drug treatment,the eggs and larva treated with different concentrations of drug were counted,and the hatching state and morphological change of eggs and larva were observed after the drug treatment.(3)In vivo animal test: Artificial infection of about 10000 Haemonchus contortus IL3 for each8-month-old male lamb,after 20 days of infection,the drug test was carried out in vivo.The ethanol extract of Melia azedarach was set as three doses,20 mg / kg,40 mg / kg and 60 mg / kg,which were administered orally,once in the morning and once in the evening,three days in a row.The reduction rate of eggs and the changes of physiological indexes of sheep before and after administration were detected.After 10 days of discontinuation,collecting the abomasum to examine the number of males and females of Haemonchus contortus.Results:(1)Vitro experiment results showed that the eggs and the larvae of Haemonchus contortus with nodrug treatment were in good activity.48 hours after the action of Melia azedarach extract,the eggs were in the state of non hatching and half hatching,while died when developed to the stage of mulberry,tadpole and larva,and the water extract and alcohol extract of Melia azedarach at different concentrations inhibited the hatching of the eggs.Among them,the alcohol extract of Melia azedarach bark had the best inhibitory effect on the hatching of the eggs.At the concentrate of 25mg/mL,the inhibition rate was reached to98.2%.At the concentration,there was a significant difference between the Melia azedaracha seed alcohol exerate and Melia azedarach bark alcohol exerate(P < 0.05).The lethal effect of Melia azedarach seed extract on infective third stage larvae was poor,only at 50 mg / mL,it had a higher lethal rate to larvae,and the mortality rate was 82.6%.When the concentration of water extract of Melia azedarach bark was 50 mg/ mL,its lethal effect on larva was particularly prominent,the mortality rate of larva was 97.0%,and the dead larva was in the shape of "linear" or "bow".By One way ANOVA there was a significant difference of lethal rate between the same concentration of Melia azedarach water extract(P < 0.05),and there was also a significant difference in the lethal rate of the same concentration of Melia azedarach alcohol extract to the larvae(P < 0.05).(2)Vitro experiment results showed that compared with the Ivermectin group,the egg reduction rate of Melia azedarach alcohol extract group was significantly lower drug treatment.The egg reduction rate of high,medium and low dose groups after drug treatment was 39.0%,31.7% and 22.8% respectively,and the corresponding EPG mean before and after administration was not significantly different(P>0.05).However,the ovulation rate of positive control group(Ivermectin group)decreased significantly after drug treatment,and the egg reduction rate was 77.4%,and the EPG mean before and after drug treatment was significantly(P<0.05).The EPG changes of Melia azedarach alcohol extract group before and after drug treatment were similar to those of the negative control group,but different from those of the positive control group.Conclusions:The results of vitro and vivo experiments showed that Melia azedarach extract inhibited the activity of eggs IL3 in vitro,25 mg / mL Melia azedarach bark alcohol extract had the best inhibitory effect on hatching of eggs among these concentrations,50 mg / mLMelia azedarach bark water extract had the most obvious lethal effect on IL3.The alcohol extract of Melia azedarach seed has a certain effect on the elimination of Haemonchus contortus in sheep.The reduction rate of eggs in the high dose group was39.0%,However,compared with the negative control group and Ivermectin group,the effect of vivo treatment is not significant.