Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cEL...Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cELISA) kit. Animals were kept healthy under field conditions, in four states: Blue Nile (n = 250), North Kordofan (n = 189), South Darfur (n = 225) and the Northern State (n = 191). Before vaccination, the overall sero-prevalence of PPRV antibodies was 54.6% (53.2% - 56%, 95% CI);high (64.8% - 76.4%, 95% CI) in Blue Nile State, medium (50.5% - 61.9%, 95% CI) in North Kordofan State and South Darfur State and low (28.6% - 35.2% 95%, CI) in Northern State. In high-risk areas (high sero-prevalence), Blue Nile (70.4%) and North Kordofan (57.7%), middle age groups (7 - 12 and 13 - 18 months) were identified as high-risk age. Middle age groups showed lower sero-prevalence than preceding (3 - 6 months) and subsequent (>18 months) age groups while the risk of exposure increased with age. Current and previous findings suggested a transmission pathway of PPRV involving the South Eastern border (Blue Nile) and neighbouring Central Sudan to North Kordofan. One month after vaccination 88.4% (343/388) of sero-negative animals were sero-converted suggesting the efficacy of the locally produced Nigeria 75/1 vaccine. Even if only individuals in the high-risk age group (7 - 18 months) were vaccinated, the overall population immunity (OPI) in high-risk areas (the Blue Nile and North Kordofan) would have surpassed the threshold of 70%, which is indicated for blocking PPRV transmission. However, lower vaccination coverage is expected in wider vaccination programmes. These findings primarily justified the targeting of PPR control in Sudan through the vaccination of high-risk age groups in high-risk areas.展开更多
In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vac...In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vaccines,although sporadic cases still occurred.However,limited information is currently available regarding the peste des petits ruminants virus(PPRV)endemic in China.Here,a PPRV strain(HLJ/13)was isolated from a field sample in China using Vero cells expressing goat signalling lymphocyte activation molecule.Phylogenetic analysis indicated that HLJ/13 belonged to lineage IV.Subsequent intranasal and subcutaneous inoculation of goats with a dose of 2×10~6 TCID50of HLJ/13 resulted in the development of typical clinical symptoms of PPR,including pyrexia,ocular and nasal discharges,stomatitis,and diarrhea.All infected goats succumbed to the disease by day 8.To gain further insight,viral loading,pathological examination and immunohistochemical analyses were conducted,elucidating the main targets of HLJ/13 as the respiratory system,digestive tract and lymphoid organs.Employing the goat infection model established above,the goat poxvirus-vectored PPR vaccine,which was previously developed and could be used as DIVA(differentiating infected from vaccinated animals)vaccine,provided complete protection against the challenge of HLJ/13.It is important to note that this study represents the first comprehensive report delineating the biology and pathogenicity characterization,and infection model of PPRV isolated in China.展开更多
[Objectives]This study was conducted to enhance the prevention and control of peste des petits ruminants(PPR)and goatpox(GTP).[Methods]Two experimental sheep farms in Northern Shandong were selected to conduct a compa...[Objectives]This study was conducted to enhance the prevention and control of peste des petits ruminants(PPR)and goatpox(GTP).[Methods]Two experimental sheep farms in Northern Shandong were selected to conduct a comparative experiment between separate vaccinations for PPR and GTP and immunization with a combined live vaccine for both diseases.Antibody levels were measured to assess immunization effect on days 7,14,21 and 28 after vaccination.[Results]The qualified rates of group immune antibodies in both the experimental and control groups exceeded 75%,achieving the goal of preventing both PPR and GTP through a single immunization.[Conclusions]This study provides clinical application references for the prevention of PPR and GTP in the local area.展开更多
Peste des Petits ruminants (PPR) is considered as one of the major constraints to the productivity of small ruminants in Sudan. Presently, control measures for PPR are primarily reliant on vaccination using an attenua...Peste des Petits ruminants (PPR) is considered as one of the major constraints to the productivity of small ruminants in Sudan. Presently, control measures for PPR are primarily reliant on vaccination using an attenuated PPR strain Nigeria 75/1 that has been produced in monolayers of Vero cells grown in static flasks. This study investigates the potential for scaling up PPR vaccine production using roller bottle technology, a more advanced method. A live, homologous vaccine against PPR in sheep and goats was successfully produced on a large scale in roller culture bottles, with DMEM supplemented with ten percent fetal bovine serum serving as the growth medium. The cells were infected with a multiplicity of infection of 0.01, and the vaccine was harvested when the cytopathic effect reached 80%. The vaccine was then freeze-dried to preserve its stability. A series of tests were conducted to ensure the safety and quality of the vaccine. Using PCR, the identity of vaccine was confirmed. It was found to be safe in both single and 100-times dose inoculations in sheep, with the produced batches showing a high titre of 6.4 ± 0.11 log10 TCID50/ml. All batches met the criteria of sterility, passing tests for bacteria, fungi, and mycoplasma. Furthermore, the vaccine proved effective in small ruminants, with antibodies persisting for over a year post-vaccination. The residual moisture content remained below 2.5%, and the vaccine successfully passed vacuum testing. Stability tests indicated that the vaccine has a shelf-life of at least one year when stored at temperatures of 2˚C - 8˚C and −20˚C. These results demonstrate the potential for applying roller bottle culture technology to PPR vaccine production, significantly streamlining the existing process and enhancing its efficiency. Further research is warranted to address the economic analyses of adopting roller bottle technology with existing PPR control program.展开更多
In this study,the decay of maternal peste des petits ruminants virus(PPRV) antibodies in kids born to goats vaccinated with Asian lineage IV PPR vaccine and the efficacy of passive immunity against PPRV was assessed t...In this study,the decay of maternal peste des petits ruminants virus(PPRV) antibodies in kids born to goats vaccinated with Asian lineage IV PPR vaccine and the efficacy of passive immunity against PPRV was assessed to determine the appropriate period for vaccination in kids.Serum samples collected from kids born to vaccinated,unvaccinated and infected goats at different time intervals were tested by PPR competitive ELISA and serum neutralization test(SNT).Maternal antibodies in kids were detectable up to 6 months with a decline trend from the third month onwards and receded below the protective level by the fourth month.The kid with an SN titre of 1:8 at the time of immunization showed significant PPRV specific antibody response(percentage inhibition of 76;SN titers >1:16),when tested on 21 day post-vaccination and was completely protected from infection upon virulent PPRV challenge.Similarly,the kid with 1:8 SN titers was completely protected from PPR infection on active challenge.Therefore,PPR vaccination is recommended in kids,aged 4 months and born to immunized or exposed goats.This could be a suitable period to avoid window of susceptibility in kids to PPRV and the effort to eliminate PPR infection from susceptible populations.展开更多
Peste des petits ruminants(PPR) is a highly contagious transboundary animal disease with a severe socio-economic impact on the livestock industry, particularly in poor countries where it is endemic. Full understanding...Peste des petits ruminants(PPR) is a highly contagious transboundary animal disease with a severe socio-economic impact on the livestock industry, particularly in poor countries where it is endemic. Full understanding of PPR virus(PPRV)pathobiology and molecular biology is critical for effective control and eradication of the disease. To achieve these goals,establishment of stable reverse genetics systems for PPRV would play a key role. Unfortunately, this powerful technology remains less accessible and poorly documented for PPRV. In this review, we discussed the current status of PPRV reverse genetics as well as the recent innovations and advances in the reverse genetics of other non-segmented negative-sense RNA viruses that could be applicable to PPRV. These strategies may contribute to the improvement of existing techniques and/or the development of new reverse genetics systems for PPRV.展开更多
This paper reports the confirmed diagnosis by nested RT-PCR of PPR cases in Tibet, China in 2007, and results of phylogenetic analysis. Results showed that the 11 tested samples were PPRV positive by nested RT-PCR, of...This paper reports the confirmed diagnosis by nested RT-PCR of PPR cases in Tibet, China in 2007, and results of phylogenetic analysis. Results showed that the 11 tested samples were PPRV positive by nested RT-PCR, of which 2 samples were genetically close to the X7443 strain (Nigeria 75/1) of lineage I, and 3 samples close to the strain AY560591 (Sungri96) of linage IV with 96.6%、97.3%、97.6% and 98% nucleotide sequence homogeneity respectively, based on partial sequencing of the F gene from 5 samples and complete sequencing of the N/M/F/H genes from one sample. This study suggested that there are at least 2 origins of PPRV in China.展开更多
Peste ties petits ruminants is a kind of acute eontagious disease infecting goats anti sheep. In this study, antibtly monitoring and tracking of healthy goat and sheep immunized by peste des petits ruminants vaccine i...Peste ties petits ruminants is a kind of acute eontagious disease infecting goats anti sheep. In this study, antibtly monitoring and tracking of healthy goat and sheep immunized by peste des petits ruminants vaccine in Changping District of Beijing City were conducted, aiming at providing a reference for the devel- opment of effective immunization procedures.展开更多
The present study deals with the co-ordination of cytokine （IL-4 and IFN-7） expression and kinetics of peste des petits ruminants （PPR） virus antigen and antibody in PPRV infected and vaccinated goats. The infecte...The present study deals with the co-ordination of cytokine （IL-4 and IFN-7） expression and kinetics of peste des petits ruminants （PPR） virus antigen and antibody in PPRV infected and vaccinated goats. The infected animals exhibited mixed cytokine （both TH1 and TH2） responses in the initial phase of the disease. The infected and dead goats had increased IFN-T response before their death; while IL-4 remained at the base level. The cytokine expression in recovered animals was almost similar to that of vaccinated ones, where a unique biphasic response of IL-4 expression was observed with an up-regulation of IFN-T on 7th days post vaccination （dpv）. Analysis of PPR virus antigen and antibody kinetics in different components of blood from infected and vaccinated animais revealed that the PPR virus antigen load was highest in plasma followed by serum and blood of the infected animals, whereas vaccinated animals showed only marginal positivity on 9th dpv. The antibody titer was high in serum followed by plasma and blood in both vaccinated and infected animals. Therefore, it is inferred that the presence of antigen and antibody were significant with the expression of cytokine, and that a decreased response of IL-4 was noticed during intermediate phase of the disease i.e., 7 to 12m days post infection （dpi）. This indicates the ability to mount a functional TH2 response after 14th dpi could be a critical determinant in deciding the survival of the PPR infected animal.展开更多
Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of P...Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of PPR disease in sheep and goats and its associated risk factors in Kassala State, Eastern Sudan. Across sectional study was conducted during the period from 30th August to 25th November 2015. The study was carried out using a structured questionnaire survey and a total of 918 blood samples were collected from apparently healthy unvaccinated sheep and goats in different localities in State of Kassala. A total of 546 sheep and 372 goats were tested for specific antibodies to nucleoprotein (NP) by competitive enzyme linked immunosorbent assay (cELISA). The apparent overall prevalence of PPR antibodies in Kassala was 58.2% while the true prevalence was calculated to be 61.3%. The apparent prevalence in sheep and goats was 68.1% and 43.5% respectively. Univariate analysis showed that the risk factors had significant associations with a cELISA positive status: locality, species, age, breed, husbandry system, housing mode, animals movement (p = 0.000) and animals sharing pasture and water (p = 0.003), while sex and newly introduced animals were not significant risk factors (p = 0.771) (p = 0.050) respectively. Factors found that significantly associated (p < 0.05) with increased odds of being cELISA positive in multivariate analysis were localities, species, age and newly introduced animals. The prevalence differed between localities and was the highest in the River Atbara (84.0%) locality, whereas it was lowest in Delta North (29.0%). No significant difference was observed among the sexes. However, the prevalence differed in different age groups and was 52.25% in animals of less than six months old;49.3% were between seven months and two years old and 65.5% were above two years old. In different husbandry systems, the prevalence was 47.9%, 73.0% and 49.2% in intensive, open grazing and pastoral systems respectively. Housing type effects were also observed;the highest prevalence was in animals housed in metal fence (83.3%). The movement pattern showed significant effect, where the prevalence was the highest (81.3%) in animals that move inter-states/inter-localities. It is concluded that the disease is endemic in Kassala State, high prevalent in sheep and goats, posing a threat to animal exportation, and may have a serious economic influence. Owners and herders should compulsorily vaccinate their animals yearly and animals should be investigated periodically for implementation of crucial eradication program.展开更多
The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in Cameroon. A total of 269 herds randomly sa...The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in Cameroon. A total of 269 herds randomly sampled across the country have been studied and 1622 samples of serum have been levied on the sheep and goat. The c-ELISA has been studied in order to detect the presence of antibodies in small ruminants like an indicator of exposition to PPRV. The results revealed the circulation of PPRV in the country with a total sero-prevalence of 39% [95%CI;37 - 41] and a sero-prevalence of 63.2% [95%CI;57.2 - 69.2] at the herd level. Sero-prevalence was variable in the ten regions ranging from 7% [95% CI;6.2 - 8.4] to 73% [95% CI;62 - 84] with the northern zone (Adamawa, North and Far-North) having 52.3% [95% CI;37 - 60] and southern zone (including the remaining seven regions) recording 29% [95% CI;11 - 57]. Similarly, it was higher in animals found in urban/peri-urban areas than in rural areas with prevalence ratio of 2.9 [95% CI 2.54 - 3.4;p < 0.001] <em>i.e. </em>3 times more, 1.6 [95% CI 1.36 - 1.90;p < 0.001] <em>i.e.</em> 1.6 times more, and 5.02 [95% CI 3.91 - 6.85;p < 0.001] <em>i.e.</em> 5 times more at national level, in the northern zone and in the southern area, respectively. Five risk factors have been identified: the breeding environment, introduction of new animals into the herds, gathering of animals for pasture and watering, wandering and transhumance. The breeding area appeared to be the most important risk factor associated with disease exposure. The control measures for the eradication of this disease must take into account the epidemiological situation, the breeding environment, animal transhumance and breeding system.展开更多
[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were ...[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value.展开更多
Invasive pests and pathogens cause immense damage globally,costing an estimated US$248 billion to the agricultural industry alone.Vehicles,such as farming and timber harvesting machinery and transportation trucks,can ...Invasive pests and pathogens cause immense damage globally,costing an estimated US$248 billion to the agricultural industry alone.Vehicles,such as farming and timber harvesting machinery and transportation trucks,can facilitate the rapid spread of biological invaders over distances far greater and more quickly than their natural dispersal ability.Understanding how frequent trips by these vehicles increase the spread of invasive agricultural and forestry pests can help inform effective biosecurity procedures before,during,or after an incursion.We used a case study of timber transport trucks in Aotearoa New Zealand to examine whether and how vehicles facilitate the spread of soil-borne pathogens between commercial forest plantations.Our results show that long-distance dispersal associated with truck movement facilitated the introduction of oomycete-like pathogens in 97% of forest sites within only one year,with pathogen loads within infected sites predicted at 84%of the sites’carrying capacity.Implementing preventative management strategies to reduce the transportation of infected soil by logging trucks,however,can reduce the spread by up to 50% after one year and reduce the pathogen load within infested sites by more than three times.Mitigating other human-assisted dispersal pathways can also help reduce spread.Reducing movement of forest visitors not involved in forestry activities,for instance,by closing forest sites to the public,can help to further reduce spread in addition to management related to harvesting activities.These results highlight the benefits of preventative management strategies in reducing the spread rate of novel soil pathogens through a high-intensity commercial forestry network but show that pest spread is still likely even with significant investment.展开更多
THE Torch Festival is the most significant and grandest celebration for all Yi communities across China’s Yunnan,Guizhou,and Sichuan provinces,with a history spanning over a thousand years.It reflects the Yi people’...THE Torch Festival is the most significant and grandest celebration for all Yi communities across China’s Yunnan,Guizhou,and Sichuan provinces,with a history spanning over a thousand years.It reflects the Yi people’s long-standing reverence for fire.Originating from the Yi ancestors’worship of fire,the festival was intended to drive away pests and evil spirits,protect crops,and represent prayers for a bountiful harvest.展开更多
The Leafminers,representing a diverse group of insects from various genera within the Agromyzidae family,pose a significant threat to spinach(Spinacia oleracea L.)production.This study aimed to identify single nucleot...The Leafminers,representing a diverse group of insects from various genera within the Agromyzidae family,pose a significant threat to spinach(Spinacia oleracea L.)production.This study aimed to identify single nucleotide polymorphism(SNP)markers associated with leafminer resistance through a genome-wide association study(GWAS)and to evaluate the prediction accuracy(PA)for selecting resistant spinach using genomic prediction(GP).Using a dataset of 84301 SNPs obtained from whole-genome resequencing,seven GWAS models,including BLINK,FarmCPU,MLM,and MLMM in GAPIT 3,as well as MLM,GLM,and SMR in TASSEL 5,were employed to perform GWAS on a panel of 286 USDA spinach germplasm accessions.Three SNP markers,namely 1_115279256_C_T,3_157082529_C_T,and 4_168510908_T_G on chromosomes 1,3,and 4,respectively,were identified as associated with leafminer resistance.In the 30 kb flanking regions of these markers,four candidate genes(SOV1g031330,SOV1g031340,SOV4g047270,and SOV4g047280),encoding LOB domain-containing protein,KH domain-containing protein,were discovered.Nodulin-like domain-containing protein,and SAM domain-containing protein,were discovered.The PA for leafminer resistance selection was estimated using ten different SNP sets,including two GWAS-derived marker sets(three and 51 SNPs)and eight random marker sets(ranging from 51 to 10 K SNPs)analyzed by seven GP models.The findings emphasized the superior performance of GWAS-derived SNP sets,reaching a PA of up to 0.79 using the cBLUP model.Notably,this research marks the pioneering application of GP in the context of insect resistance,providing a significant advancement in the understanding and management of leafminer resistance in spinach cultivation.展开更多
文摘Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cELISA) kit. Animals were kept healthy under field conditions, in four states: Blue Nile (n = 250), North Kordofan (n = 189), South Darfur (n = 225) and the Northern State (n = 191). Before vaccination, the overall sero-prevalence of PPRV antibodies was 54.6% (53.2% - 56%, 95% CI);high (64.8% - 76.4%, 95% CI) in Blue Nile State, medium (50.5% - 61.9%, 95% CI) in North Kordofan State and South Darfur State and low (28.6% - 35.2% 95%, CI) in Northern State. In high-risk areas (high sero-prevalence), Blue Nile (70.4%) and North Kordofan (57.7%), middle age groups (7 - 12 and 13 - 18 months) were identified as high-risk age. Middle age groups showed lower sero-prevalence than preceding (3 - 6 months) and subsequent (>18 months) age groups while the risk of exposure increased with age. Current and previous findings suggested a transmission pathway of PPRV involving the South Eastern border (Blue Nile) and neighbouring Central Sudan to North Kordofan. One month after vaccination 88.4% (343/388) of sero-negative animals were sero-converted suggesting the efficacy of the locally produced Nigeria 75/1 vaccine. Even if only individuals in the high-risk age group (7 - 18 months) were vaccinated, the overall population immunity (OPI) in high-risk areas (the Blue Nile and North Kordofan) would have surpassed the threshold of 70%, which is indicated for blocking PPRV transmission. However, lower vaccination coverage is expected in wider vaccination programmes. These findings primarily justified the targeting of PPR control in Sudan through the vaccination of high-risk age groups in high-risk areas.
基金supported by the National Key Research and Development Program of China(2016YFD0500108)the International S&T Cooperation Program of China(ISTCP)(2015DFA31300)。
文摘In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vaccines,although sporadic cases still occurred.However,limited information is currently available regarding the peste des petits ruminants virus(PPRV)endemic in China.Here,a PPRV strain(HLJ/13)was isolated from a field sample in China using Vero cells expressing goat signalling lymphocyte activation molecule.Phylogenetic analysis indicated that HLJ/13 belonged to lineage IV.Subsequent intranasal and subcutaneous inoculation of goats with a dose of 2×10~6 TCID50of HLJ/13 resulted in the development of typical clinical symptoms of PPR,including pyrexia,ocular and nasal discharges,stomatitis,and diarrhea.All infected goats succumbed to the disease by day 8.To gain further insight,viral loading,pathological examination and immunohistochemical analyses were conducted,elucidating the main targets of HLJ/13 as the respiratory system,digestive tract and lymphoid organs.Employing the goat infection model established above,the goat poxvirus-vectored PPR vaccine,which was previously developed and could be used as DIVA(differentiating infected from vaccinated animals)vaccine,provided complete protection against the challenge of HLJ/13.It is important to note that this study represents the first comprehensive report delineating the biology and pathogenicity characterization,and infection model of PPRV isolated in China.
基金Supported by Shandong Provincial Sheep Industry Technology System Position Expert Project(SDAIT-10-06)Binzhou Municipal Science and Technology Innovation Policy Guidance Plan Project for the Agricultural Social Service Field(2023SHFZ004).
文摘[Objectives]This study was conducted to enhance the prevention and control of peste des petits ruminants(PPR)and goatpox(GTP).[Methods]Two experimental sheep farms in Northern Shandong were selected to conduct a comparative experiment between separate vaccinations for PPR and GTP and immunization with a combined live vaccine for both diseases.Antibody levels were measured to assess immunization effect on days 7,14,21 and 28 after vaccination.[Results]The qualified rates of group immune antibodies in both the experimental and control groups exceeded 75%,achieving the goal of preventing both PPR and GTP through a single immunization.[Conclusions]This study provides clinical application references for the prevention of PPR and GTP in the local area.
文摘Peste des Petits ruminants (PPR) is considered as one of the major constraints to the productivity of small ruminants in Sudan. Presently, control measures for PPR are primarily reliant on vaccination using an attenuated PPR strain Nigeria 75/1 that has been produced in monolayers of Vero cells grown in static flasks. This study investigates the potential for scaling up PPR vaccine production using roller bottle technology, a more advanced method. A live, homologous vaccine against PPR in sheep and goats was successfully produced on a large scale in roller culture bottles, with DMEM supplemented with ten percent fetal bovine serum serving as the growth medium. The cells were infected with a multiplicity of infection of 0.01, and the vaccine was harvested when the cytopathic effect reached 80%. The vaccine was then freeze-dried to preserve its stability. A series of tests were conducted to ensure the safety and quality of the vaccine. Using PCR, the identity of vaccine was confirmed. It was found to be safe in both single and 100-times dose inoculations in sheep, with the produced batches showing a high titre of 6.4 ± 0.11 log10 TCID50/ml. All batches met the criteria of sterility, passing tests for bacteria, fungi, and mycoplasma. Furthermore, the vaccine proved effective in small ruminants, with antibodies persisting for over a year post-vaccination. The residual moisture content remained below 2.5%, and the vaccine successfully passed vacuum testing. Stability tests indicated that the vaccine has a shelf-life of at least one year when stored at temperatures of 2˚C - 8˚C and −20˚C. These results demonstrate the potential for applying roller bottle culture technology to PPR vaccine production, significantly streamlining the existing process and enhancing its efficiency. Further research is warranted to address the economic analyses of adopting roller bottle technology with existing PPR control program.
基金Project Directorate on Animal Disease Monitoring and Surveillance(PD_ADMAS)
文摘In this study,the decay of maternal peste des petits ruminants virus(PPRV) antibodies in kids born to goats vaccinated with Asian lineage IV PPR vaccine and the efficacy of passive immunity against PPRV was assessed to determine the appropriate period for vaccination in kids.Serum samples collected from kids born to vaccinated,unvaccinated and infected goats at different time intervals were tested by PPR competitive ELISA and serum neutralization test(SNT).Maternal antibodies in kids were detectable up to 6 months with a decline trend from the third month onwards and receded below the protective level by the fourth month.The kid with an SN titre of 1:8 at the time of immunization showed significant PPRV specific antibody response(percentage inhibition of 76;SN titers >1:16),when tested on 21 day post-vaccination and was completely protected from infection upon virulent PPRV challenge.Similarly,the kid with 1:8 SN titers was completely protected from PPR infection on active challenge.Therefore,PPR vaccination is recommended in kids,aged 4 months and born to immunized or exposed goats.This could be a suitable period to avoid window of susceptibility in kids to PPRV and the effort to eliminate PPR infection from susceptible populations.
基金supported by the National Key Research and Development Program of China (2016YFD0500108 and 2016YFE0204100)the International Cooperation Project of CAAS Innovation Program (CAAS-GJHZ201700X)
文摘Peste des petits ruminants(PPR) is a highly contagious transboundary animal disease with a severe socio-economic impact on the livestock industry, particularly in poor countries where it is endemic. Full understanding of PPR virus(PPRV)pathobiology and molecular biology is critical for effective control and eradication of the disease. To achieve these goals,establishment of stable reverse genetics systems for PPRV would play a key role. Unfortunately, this powerful technology remains less accessible and poorly documented for PPRV. In this review, we discussed the current status of PPRV reverse genetics as well as the recent innovations and advances in the reverse genetics of other non-segmented negative-sense RNA viruses that could be applicable to PPRV. These strategies may contribute to the improvement of existing techniques and/or the development of new reverse genetics systems for PPRV.
基金This work was supported by project from MOA [2006-G57(3)B-Z1] Project from Yunnan Province (2008LA019)
文摘This paper reports the confirmed diagnosis by nested RT-PCR of PPR cases in Tibet, China in 2007, and results of phylogenetic analysis. Results showed that the 11 tested samples were PPRV positive by nested RT-PCR, of which 2 samples were genetically close to the X7443 strain (Nigeria 75/1) of lineage I, and 3 samples close to the strain AY560591 (Sungri96) of linage IV with 96.6%、97.3%、97.6% and 98% nucleotide sequence homogeneity respectively, based on partial sequencing of the F gene from 5 samples and complete sequencing of the N/M/F/H genes from one sample. This study suggested that there are at least 2 origins of PPRV in China.
文摘Peste ties petits ruminants is a kind of acute eontagious disease infecting goats anti sheep. In this study, antibtly monitoring and tracking of healthy goat and sheep immunized by peste des petits ruminants vaccine in Changping District of Beijing City were conducted, aiming at providing a reference for the devel- opment of effective immunization procedures.
文摘The present study deals with the co-ordination of cytokine （IL-4 and IFN-7） expression and kinetics of peste des petits ruminants （PPR） virus antigen and antibody in PPRV infected and vaccinated goats. The infected animals exhibited mixed cytokine （both TH1 and TH2） responses in the initial phase of the disease. The infected and dead goats had increased IFN-T response before their death; while IL-4 remained at the base level. The cytokine expression in recovered animals was almost similar to that of vaccinated ones, where a unique biphasic response of IL-4 expression was observed with an up-regulation of IFN-T on 7th days post vaccination （dpv）. Analysis of PPR virus antigen and antibody kinetics in different components of blood from infected and vaccinated animais revealed that the PPR virus antigen load was highest in plasma followed by serum and blood of the infected animals, whereas vaccinated animals showed only marginal positivity on 9th dpv. The antibody titer was high in serum followed by plasma and blood in both vaccinated and infected animals. Therefore, it is inferred that the presence of antigen and antibody were significant with the expression of cytokine, and that a decreased response of IL-4 was noticed during intermediate phase of the disease i.e., 7 to 12m days post infection （dpi）. This indicates the ability to mount a functional TH2 response after 14th dpi could be a critical determinant in deciding the survival of the PPR infected animal.
文摘Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of PPR disease in sheep and goats and its associated risk factors in Kassala State, Eastern Sudan. Across sectional study was conducted during the period from 30th August to 25th November 2015. The study was carried out using a structured questionnaire survey and a total of 918 blood samples were collected from apparently healthy unvaccinated sheep and goats in different localities in State of Kassala. A total of 546 sheep and 372 goats were tested for specific antibodies to nucleoprotein (NP) by competitive enzyme linked immunosorbent assay (cELISA). The apparent overall prevalence of PPR antibodies in Kassala was 58.2% while the true prevalence was calculated to be 61.3%. The apparent prevalence in sheep and goats was 68.1% and 43.5% respectively. Univariate analysis showed that the risk factors had significant associations with a cELISA positive status: locality, species, age, breed, husbandry system, housing mode, animals movement (p = 0.000) and animals sharing pasture and water (p = 0.003), while sex and newly introduced animals were not significant risk factors (p = 0.771) (p = 0.050) respectively. Factors found that significantly associated (p < 0.05) with increased odds of being cELISA positive in multivariate analysis were localities, species, age and newly introduced animals. The prevalence differed between localities and was the highest in the River Atbara (84.0%) locality, whereas it was lowest in Delta North (29.0%). No significant difference was observed among the sexes. However, the prevalence differed in different age groups and was 52.25% in animals of less than six months old;49.3% were between seven months and two years old and 65.5% were above two years old. In different husbandry systems, the prevalence was 47.9%, 73.0% and 49.2% in intensive, open grazing and pastoral systems respectively. Housing type effects were also observed;the highest prevalence was in animals housed in metal fence (83.3%). The movement pattern showed significant effect, where the prevalence was the highest (81.3%) in animals that move inter-states/inter-localities. It is concluded that the disease is endemic in Kassala State, high prevalent in sheep and goats, posing a threat to animal exportation, and may have a serious economic influence. Owners and herders should compulsorily vaccinate their animals yearly and animals should be investigated periodically for implementation of crucial eradication program.
文摘The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in Cameroon. A total of 269 herds randomly sampled across the country have been studied and 1622 samples of serum have been levied on the sheep and goat. The c-ELISA has been studied in order to detect the presence of antibodies in small ruminants like an indicator of exposition to PPRV. The results revealed the circulation of PPRV in the country with a total sero-prevalence of 39% [95%CI;37 - 41] and a sero-prevalence of 63.2% [95%CI;57.2 - 69.2] at the herd level. Sero-prevalence was variable in the ten regions ranging from 7% [95% CI;6.2 - 8.4] to 73% [95% CI;62 - 84] with the northern zone (Adamawa, North and Far-North) having 52.3% [95% CI;37 - 60] and southern zone (including the remaining seven regions) recording 29% [95% CI;11 - 57]. Similarly, it was higher in animals found in urban/peri-urban areas than in rural areas with prevalence ratio of 2.9 [95% CI 2.54 - 3.4;p < 0.001] <em>i.e. </em>3 times more, 1.6 [95% CI 1.36 - 1.90;p < 0.001] <em>i.e.</em> 1.6 times more, and 5.02 [95% CI 3.91 - 6.85;p < 0.001] <em>i.e.</em> 5 times more at national level, in the northern zone and in the southern area, respectively. Five risk factors have been identified: the breeding environment, introduction of new animals into the herds, gathering of animals for pasture and watering, wandering and transhumance. The breeding area appeared to be the most important risk factor associated with disease exposure. The control measures for the eradication of this disease must take into account the epidemiological situation, the breeding environment, animal transhumance and breeding system.
基金Supported by The National Project for the Prevention and Control of Major Exotic Animal Diseases(2022YFD1800500)National Mutton Sheep Industrial Technology System(CARS39).
文摘[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value.
基金supported by the Forest Growers Levy Trust(QT-10353)the Ministry for Primary Industries and the Sustainable Food and Fibre Futures fund(SFFF22023)the Strategic Science Investment Fund(CO4X1703)for funding this research.
文摘Invasive pests and pathogens cause immense damage globally,costing an estimated US$248 billion to the agricultural industry alone.Vehicles,such as farming and timber harvesting machinery and transportation trucks,can facilitate the rapid spread of biological invaders over distances far greater and more quickly than their natural dispersal ability.Understanding how frequent trips by these vehicles increase the spread of invasive agricultural and forestry pests can help inform effective biosecurity procedures before,during,or after an incursion.We used a case study of timber transport trucks in Aotearoa New Zealand to examine whether and how vehicles facilitate the spread of soil-borne pathogens between commercial forest plantations.Our results show that long-distance dispersal associated with truck movement facilitated the introduction of oomycete-like pathogens in 97% of forest sites within only one year,with pathogen loads within infected sites predicted at 84%of the sites’carrying capacity.Implementing preventative management strategies to reduce the transportation of infected soil by logging trucks,however,can reduce the spread by up to 50% after one year and reduce the pathogen load within infested sites by more than three times.Mitigating other human-assisted dispersal pathways can also help reduce spread.Reducing movement of forest visitors not involved in forestry activities,for instance,by closing forest sites to the public,can help to further reduce spread in addition to management related to harvesting activities.These results highlight the benefits of preventative management strategies in reducing the spread rate of novel soil pathogens through a high-intensity commercial forestry network but show that pest spread is still likely even with significant investment.
文摘THE Torch Festival is the most significant and grandest celebration for all Yi communities across China’s Yunnan,Guizhou,and Sichuan provinces,with a history spanning over a thousand years.It reflects the Yi people’s long-standing reverence for fire.Originating from the Yi ancestors’worship of fire,the festival was intended to drive away pests and evil spirits,protect crops,and represent prayers for a bountiful harvest.
基金supported by USDA-SCRI(Grant Nos.2017-51181-26830 and 2023-51181-41321)USDA-AMS SCMP(Grant No.16SCCMAR0001)+1 种基金Arkansas Department of Agriculture SCBGP(Grant No.AM22SCBGPAR1130-00)USDA NIFA Hatch project ARK0VG2018 and ARK02440.
文摘The Leafminers,representing a diverse group of insects from various genera within the Agromyzidae family,pose a significant threat to spinach(Spinacia oleracea L.)production.This study aimed to identify single nucleotide polymorphism(SNP)markers associated with leafminer resistance through a genome-wide association study(GWAS)and to evaluate the prediction accuracy(PA)for selecting resistant spinach using genomic prediction(GP).Using a dataset of 84301 SNPs obtained from whole-genome resequencing,seven GWAS models,including BLINK,FarmCPU,MLM,and MLMM in GAPIT 3,as well as MLM,GLM,and SMR in TASSEL 5,were employed to perform GWAS on a panel of 286 USDA spinach germplasm accessions.Three SNP markers,namely 1_115279256_C_T,3_157082529_C_T,and 4_168510908_T_G on chromosomes 1,3,and 4,respectively,were identified as associated with leafminer resistance.In the 30 kb flanking regions of these markers,four candidate genes(SOV1g031330,SOV1g031340,SOV4g047270,and SOV4g047280),encoding LOB domain-containing protein,KH domain-containing protein,were discovered.Nodulin-like domain-containing protein,and SAM domain-containing protein,were discovered.The PA for leafminer resistance selection was estimated using ten different SNP sets,including two GWAS-derived marker sets(three and 51 SNPs)and eight random marker sets(ranging from 51 to 10 K SNPs)analyzed by seven GP models.The findings emphasized the superior performance of GWAS-derived SNP sets,reaching a PA of up to 0.79 using the cBLUP model.Notably,this research marks the pioneering application of GP in the context of insect resistance,providing a significant advancement in the understanding and management of leafminer resistance in spinach cultivation.
