Study On The Biological Characteristics, Harmfulness And Control Methods Of Psoroptes Ovis

This study detaily investigated the prevalence and occurrence of Psoroptes ovis disease in southern and northern Xinjiang.Through the infected animal testing,simultaneously tracking survey,we studied the activities of life of Psoroptes ovis,such as growth, development,reproduction and parasitic habits et tal by using the itch mite ecology,revealing the regularity and harmfulness of the occurrence of Psoroptes ovis disease in the specific geographical environment and climatic condition in Xinjing and on the basis of these,we deeply studied the early diagnosis and method to this disease judgment in order to control the occurrence of this disease.This study obtained significant progress in the following aspects:1.The survey on the prevalence and reason of occurence of Psoroptes ovis disease in the recamation area in Xinjiang showed that:the prevalence of Psoroptes ovis disease had group and regional characters.The management of the flow of sheep lacked preventional awareness leading to the occurrence of the disease;otherwise,there was no unified measure system and the choice of oral and injecetable drugs in place of drug-bath and the control management, supervision of the drug-bath and drug quality et al made contribute to the prevalence of this disease.2.The survey on the dynamic seanon occurrence and the forms of communication revealed that:this disease had a high rate of occurrence in spring,autumn and winter.In spring,the duration of this disease was very short,but the development of Psoroptes ovis was controled in the hot and dry summer(June～July) and came to delitescence;this disease lasted the longest time in autumn and the harmness was also the most serious and then sheep itch mite came into delitescence in the cold winter.Our research also showed that the direct contaction of sheep was the mian way for the diffusion of this disease.For the large temperture difference in spring and autumn season,the intimate contact of sheep in night can directly cause the rapid spread of this disease.3.The survey on the biological characteristics of Psoroptes ovis showed that:the developed four stages inculding egg,hexapod larva,octopod nymphs and octopod adult males and females。on the suitable climate condition,the breeding cycle(from eggs to lay eggs again) approximately lasts 12 d and a female itch mite can produce an egg daily.Factors,such as temperature,humidity,light intensity and et al,had an obvious impact on the development and activities of Psoroptes ovis.Psoroptes ovis showed strong sensitivity,adaptation and endurance to the environment and negative phototaxis,photophobia and afaird high fever.The study on the vitro body Psoroptes ovis at natural variable and constant temperature showed that temperature had a remarkable effect on the egging,hatching,static molting and phases of the development of itch mite,such as 30℃is the optimal temperature for itch mite to develop,the trend of growth ratardtation was prolonged at 20～26℃and the temperture which was higher than 40℃or lower than 10℃would lead to the growth disruption and speed up the death.4.The survey on the harmness of the parastic erosion of the sheep itch mite showed that: the form of the sheep itch mite parasitization was first spot,and then gradually diffused to the surrounding and reformed focus which connacted with other focus with the development of the disease.Finally,the parastic erosion was laminated.Meanwhile,the degree of injury on the dermal tissue of the host was aggravated with the duration of the parasitization.The survey on the in vitro Psoroptes ovis reputed into animals showed that:in virto Psoroptes ovis had a strong ability to tolerate low temperature and resistant hunger.Once it survived in the environment and it can also cause the same erosion hazard after reputted the tha sheep body.5.The study on the early disease diagnose,pathogenesis judgement and disease prevention showed that:we can judge the period of the parasization according to the size of the disease focus in the host,the degree of erosion.According to the biological characters, such as photophobia and fear hot,we can detect the pathogeny by using the heating and lighting methods which are very suitable for the farms and grazing field with no laboratory and also simple and accurate.And then we can we can take corresponding measures and then reduce the injury to the minimize.