| Hemotropic Mycoplasma(Hemoplasmas)is a pathogen that parasitizes on the surface of host red blood cells,plasma and bone marrow.The main clinical features of hemoplasmas are anemia,high fever,jaundice,emaciation and miscarriage.In this study,PCR method was used to investigate the infection situation of hemoplasmas of sheep in southern Xinjiang,and to identify the pathogen species,aiming to grasp hemoplasmas prevalence and pathogen species distribution characteristics.1.In order to understand the infection situation of hemoplasmas in sheep in southern Xinjiang.A total of 595 blood DNA samples of adult sheep collected from 21 districts and counties in southern Xinjiang from June 2015 to July 2016.A total of 595 blood DNA samples were detected by PCR method.The total infection rate of hemoplasmas in sheep was 19.8%(118/595),and the infection rate of hemoplasmas in sheep in Bachu County was the highest,which was 60.0%(21/35).The infection rate of hemoplasmas in sheep among different survey sites was statistically significant(P < 0.01).The infection rate of hemoplasmas in sheep in summer and winter were 18.9%(40/212)and 20.4%(78/383),respectively,with no statistical difference(P > 0.05).The infection rate of hemoplasmas in free-range and captive sheep were22.6%(95/421)and 13.2%(23/174),respectively,with statistically significant differences(P < 0.01).All118 positive samples were sequenced,and 4 species of hemoplasmas were identified by sequence alignment analysis.The infection rate of Mycoplasma ovis,Candidatus Mycoplasma haemovis,Mycoplasma wenyonii and Candidatus Mycoplasma haemobos were 16.0%(95/595),1.3%(8/595),2.2%(13/595)and 0.2%(1/595),respectively.Among them,the pending species of Mycoplasma ovis and Candidatus Mycoplasma haemovis have one genotype each,while the pending species of Mycoplasma wenyonii and Candidatus Mycoplasma haemobos have two genotypes each.2.In order to thorough understand the infection situation of hemoplasmas in sheep of different age groups in large-scale sheep farms in southern Xinjiang.A total of 334 sheep blood DNA samples collected from 3 large-scale sheep farms in southern Xinjiang.A total of 334 sheep blood DNA samples were detected by PCR method.The total infection rate of hemoplasmas in sheep was 55.4%(185/334).The infection rate of hemoplasmas in large-scale sheep farms in Aksu,Bachu and Cele was 88.0%(81/92),22.5%(27/120)and 63.1%(77/122),respectively,with statistically significant(P < 0.01).The infection rate of 3-6 months old lambs was the highest,which was 67.4%(62/92),and the infection rate of hemoplasmas in < 3 months old lambs,< 7-1 years old and > 1 years old sheep were 23.3%(14/60),63.3%(57/90)and 56.5%(52/92),respectively,with statistically significant difference(P < 0.01).All 185 positive samples were sequenced,and 4 species of hemoplasmas were identified by sequence alignment analysis.The infection rate of Mycoplasma ovis,Candidatus Mycoplasma haemovis,Mycoplasma wenyonii wenyonii and Candidatus Mycoplasma haemobos were 46.7%(156/334),3.6%(12/334),1.5%(5/334)and1.2%(4/334),respectively.Among them,Mycoplasma ovis,Candidatus Mycoplasma haemovis,Mycoplasma wenyonii and Candidatus Mycoplasma haemobos have 2 genotypes each.In conclusion,the sheep are commonly infected with hemoplasmas in southern Xinjiang,and free-range sheep are more susceptible than captive sheep,with the highest susceptibility of lambs in aged3-6 months.The commonly infected species of hemoplasmas include Mycoplasma ovis,Candidatus Mycoplasma haemovis,Mycoplasma wenyonii and Candidatus Mycoplasma haemobos,among them Mycoplasma ovis as the dominant species.The research results suggest that the prevention and control of vector insects should be paid attention to in the process of sheep feeding,and the feeding management and environmental sanitation during weaning period should be strengthened. |
