Serologic and molecular survey for major viral pathogens in grazing hybrid wild boars in Northeast China

Hybrid wild boar husbandry is an important component of livestock production in Northeast China.However,the current disease situation of these animals is largely unknown due to a lack of disease surveillance.The present study was conducted to determine the prevalence of several important viral diseases in the hybrid wild boar population of Northeast China.Between September 2015 to December 2016,169 blood and 61 tissue samples were collected from apparently healthy hybrid wild boars from farms in Jilin,Inner Mongolia and Heilongjiang provinces.ELISA detected serum antibodies against classical swine fever virus(CSFV),porcine reproductive and respiratory syndrome virus(PRRSV),pseudorabies virus(PRV),porcine circovirus type 2(PCV2)and Japanese encephalitis virus(JEV),but not against African swine fever virus(ASFV),with PCV2 having the highest seropositive rate(87.2–100%in different farms).RT-PCR or PCR performed on the processed samples detected only PCV2,with 33.1%(56/169)of blood samples and 32.8%(20/61)of spleen samples being positive,respectively,indicating widespread PCV2 infection in hybrid wild boars.Phylogenetic analysis of 15 PCV2 ORF2 sequences showed that they belong to genotypes PCV2a,PCV2b and PCV2d,with nucleotide and deduced amino acid homologies of 88.5–100%and 88.1–100%,respectively.

A Survey of Wild Birds Trading in the Beijing Bird Markets

Birds are an indispensable part of nature andthey play an important role in maintaining an ecologicalbalance. The existence of bird markets undoubtedlyposes a threat to the population of wild birds. Thegeographical location of Beijing is paramount to themigratory birds. The species of birds are rich in varietyand its quantity is large in scale. In addition, the birdmarket in old town Beijing has a long history - since theQing Dynasty, it has been the main bird market in thecity. Therefore, a survey of the major bird markets inthe city is highly representative. This study investigatedthe types, quantities, and prices of wild birds tradedin several major bird markets in Beijing from July16 to July 18, 2019. Data analysis and collation werealso conducted in this study. The results of the surveypresented 26 kinds of wild birds, with a total tradingvolume of an estimated 253. They are mainly birdsof the order of the passerine, 18 of which are underBeijing’s second-class protection, and one of them isunder first-class protection.

Canada’s inter-agency wild bird influenza survey

Canada’s Inter-agency Wild Bird Influenza Survey,which started in 2005,and is a collaborative effort among federal,provincial and territorial government agencies as well as non-governmental organizations and academic institutions,has two components:(i)a seasonal survey of live wild waterfowl species from selected geographic regions across Canada(to expand our understanding of the avian influenza viruses circulating in wild bird populations);and(ii)an ongoing survey of birds found dead that are submitted to a regional diagnostic laboratory(to enhance detection of highly pathogenic avian influenza strains).Combined swabs from the cloaca and oro-pharynx collected from each bird are screened using a real-time reverse transcriptase-polymerase chain reaction(RRT-PCR)that targets a unique segment of the influenza A M1 gene.If the M1 result is positive or inconclusive,RRT-PCR for gene segments of the H5 and H7 hemagglutinin subtypes are performed.All samples that are RRT-PCR positive for H5 or H7 are sent immediately for test confirmation and further characterization.All field and laboratory data are entered into a database developed and maintained by the Canadian Cooperative Wildlife Health Centre.Since the survey commenced in 2005,on average,30%of all live ducks sampled,5%of other species of live birds and 3%of birds found dead have tested positive for avian influenza,all of North American lineage and of low pathogenicity.