| Anaplasma has become an important tick-borne pathogen that is harmful to human and animal health worldwide in recent years.This tick-borne Gram-negative parasite mainly infects the blood cells of ruminant animals such as cattles and sheep.It can lead to clinical symptoms such as high fever,anemia,jaundice,emaciation when human and animal infected,even case death in severe cases.Even after the clinical cure will also carry Anaplasma in whole life,become the persistent infestor.So far,7 species of An aplasma have been reported,including A.phagocytophilum,A.bovis,A.ovis,A.marginale,A.centrale,A.platys and A.capra,some of these species can infect people and livestock.Although a variety of Anaplasma can lead to bovine Anaplasmosis,the main pathogens is A.marginale.Ixide is the main vectors of Anaplasma.With the comprehensive development of forestry and animal husbandry resources and the developing of social economy in China,people have more opportunities to contact with the hard ticks,which seriously threatens the health of people and the development of breeding industry in China.Therefore,it is of great significance to find out the situation of Anaplasma infection in cattles,hard ticks species and carrying Anaplasma to assess the risk of bovine Anaplasmosis,hard ticks and ensure the healthy development of cattle industry and public health safety.1.Molecular epidemiological investigation of Anaplasma of cattle in Henan ProvinceBlood smear giemsa staining method and Polymerase chain reaction(PCR)method were applied to test the pervalence status of Anplasma of 1070 bovine blood samples collected from North Henan,South Henan,western Henan,Eastern Henan and Central Henan.The results showed that the total Anplasma infection rate of cattle was 11.68%(125/1070),and that A.phagocytophilum,A.bovis,A.ovis,A.marginale,A.capra,A.platys were 2.43%(26/1070),3.18%(34/1070),1.68%(18/1070),2.99%(32/1070),2.80%(30/1070),2.52%(27/1070),respectively.There was significant difference in Anplasma infection condition in different regions(P<0.01).The Anplasma positive rate of cattle in North Henan,South Henan,West Henan,East Henan and Central Henan were 12.10%(34/281),16.92%(34/201),10.80%(27/250),18.84%(26/138)and 2.00%(4/200),respectively.There was a significant difference in the Anplasma positive rate among different feeding modes(P<0.01),and the positive rate of Anplasma in stabling and grazing cattle was 10.24%(105/1025)and 44.44%(20/45),respectively.There was significant difference in the rate of Anplasma positive among different breeds(P<0.01).The positive rate of Anplasma in dairy cattle and beef cattle was 6.24%(50/801)and 27.88%(75/269),respectively.The positive rate of Anplasma in cattle aged ≤24 months and 24 months were 16.92%(55/325)and 8.46%(70/745),had a extremely significant difference(P<0.01).The positive rate of Anplasma in cattle(11.81%,119/1008)was higher than bulls(9.68%,6/62),but the difference was not significant(P>0.05).The positive rate of Anplasma in autumn(13.38%,63/471)was higher than that in summer(10.35%,62/599),but the difference was not significant(P>0.05).The cattle infected with two or more kinds of Anplasma were 2.52%(27/1070)and 0.84%(9/1070),respectively.In this study,it was found that Anaplasma spread in cattle in different regions of Henan and showed mixed infection,and for the first time,A.capra infection was found in Chinese cattle.The infections of Anaplasma in cattle was significantly related to region,feeding method,breed and age.The epidemic situation of Anplasma in cattle in Henan has been proved,which enriched the epidemiological data of Anplasma,and provided a reference for the prevention and control of Anplasmosis.2.Investigation of hard tick species and tick-borne Anaplasma in some areas of Henan ProvineMorphological and PCR methods were used to investigate the tick species and carrying anaplasma condition of 103 hard ticks collected from 4 regions in Boai,Qinyang,Yiyang and Ruyang cities of Henan Province from July 2018 to September 2020.Hard ticks collected were identified as belonging to 3 species and 3 genera,Haemaphysalis(H.longicornis),Hyalomma(H.detritum)and Rhipicephalus(R.microplus),of which H.longicornis accounted for the largest proportion,90.29%(93/103).The total positive rate was 41.75%(43/103).The positive rates of A.phagocytophilum,A.bovis,A.ovis,A.capra,A.marginale,A.plotys were 5.83%(6/103),17.48%(18/103),6.80%(7/103),11.65%(12/103),9.71%(10/103)and 5.83%(6/103),respectively.The positive rate of hard ticks carrying two or more species of Anplasma was 12.62%(13/103).The positive rates of Boai,Qinyang,Yiyang and Ruyang hard ticks carring Anplasma were 40.74%(11/27),10.00%(1/10),32.26%(10/31)and 60.00%(21/35),respectively,and the differences were significant(0.01<P<0.05).There was no significant difference in the Anplasma positive rate among different genders,species and host origin hard ticks(P>0.05).In this study,it is found that H.longicornis is the dominant species in the surveyed area and can carry a variety of Anaplasma,and Anaplasma is also common in hard ticks of Henan.The sex,breed and animal host of the hard ticks have no significant influence on infections of Anaplasma.The distribution of hard ticks species and their Anplasma carrying status in some areas of Henan province were ascertsined,providing an important reference for the prevention and control of hard ticks and Anaplasmosis.3.Genetic evolution analysis of Anaplasma in cattles,hard ticks species and carrying Anaplasma in Hennan provincePCR method were applied to test prevalence staus of Anaplasma of 1070 cattles blood and 103 ticks samples collected from different areas in Henan province and hard ticks species identification.A.cytophilum,A.bovis and A.platys based on 1 6s rRNA genes of hard ticks,A.capra based on gltA genes,A.ovis and A.marginale based on Msp4 genes,for the construction of the genetic evolutionary tree.By analyzing the genetic evolution of hard ticks and Anaplasma,15 new genotypes of Anaplasma and 7 new genotypes of hard ticks were obtained.There are 5 A.phagocytophilum(A.phagocytophilum Cattle SQ,A.phagocytophilum Cattle JZ,A.phagocytophilum Cattle SQ2,A.phagocytophilum Cattle LY2,A.phagocytophilum Cattle XY),4 A.bovis(A.bovis Cattle SHQ,A.bovis Cattle XY,A.bovis Cattle AY,A.bovis Cattle ZK),3 A.ovis(A.ovis Cattle PDS,A.ovis Tick RY,A.ovis Tick RY3),3 A.platys(A.platys cattle/tick LY2,A.platys cattle LY,A.platys cattle XY)and 5 H.longicornis(H.longicornis JZ1,H.longicornis JZ2,H.longicornis JZ4,H.longicornis LY1,H.longicornis LY2),1 detritum(H.detritum cattle JZ),1 R.microplus(R.microplus cattle/grass LY)new genotypes.Through this research,it is found that both H.longicornis and Anaplasma have genetic diversity.A total of 22 new genotypes have been obtained,which enriches the genebank of Anaplasma and hard ticks,and to supplement the data for molecular biology analysis of Anaplasma and hard ticks for the later stage. |
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