Avian PathologyPub Date : 2024-10-01Epub Date: 2024-04-10DOI: 10.1080/03079457.2024.2336091
Abderrahmen Rahmani, Hamza Ahmed Laloui, Radhouane Kara, Mohamed Abdesselem Dems, Nora Cherb, Abdenour Klikha, Damer P Blake
{"title":"The financial cost of coccidiosis in Algerian chicken production: a major challenge for the poultry sector.","authors":"Abderrahmen Rahmani, Hamza Ahmed Laloui, Radhouane Kara, Mohamed Abdesselem Dems, Nora Cherb, Abdenour Klikha, Damer P Blake","doi":"10.1080/03079457.2024.2336091","DOIUrl":"10.1080/03079457.2024.2336091","url":null,"abstract":"<p><p>Coccidiosis, caused by parasites of the genus <i>Eimeria</i>, is a significant economic burden to the poultry industry. In this study, we conducted a comprehensive analysis to evaluate the financial losses associated with <i>Eimeria</i> infection in chickens in Algeria, relying on data provided by key stakeholders in the Algerian poultry industry to assess sub-clinical as well as clinical impact. We employed the updated 2020 version of a model established to estimate the cost of coccidiosis in chickens, taking into consideration specific cultural and technical aspects of poultry farming in Algeria. The findings predict economic losses due to coccidiosis in chickens of approximately £86.7 million in Algeria for the year 2022, representing £0.30 per chicken raised. The majority of the cost was attributed to morbidity (74.9%), emphasizing the substantial economic impact of reduced productivity including decreased bodyweight gain and increased feed conversion ratio. Costs associated with control measures made up 20.5% of the total calculated cost, with 4.6% of the cost related to mortality. These figures provide a clear indication of the scope and economic impact of <i>Eimeria</i> infection of chickens in Algeria, illustrating the impact of practices common across North Africa. They underscore the ongoing requirement for effective preventive and control measures to reduce these financial losses while improving productivity and welfare, ensuring the economic sustainability of the Algerian poultry industry.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"368-379"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140288093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Identification of B-cell epitopes located on the surface in the PB2 protein of the H9N2 subtype avian influenza virus.","authors":"Yiqin Cai, Guihu Yin, Xiangyu Huang, Jianing Hu, Zichen Gao, Xinyu Guo, Yawei Qiu, Haifeng Sun, Xiuli Feng","doi":"10.1080/03079457.2024.2338816","DOIUrl":"10.1080/03079457.2024.2338816","url":null,"abstract":"<p><p>Avian influenza (AI), caused by H9N2 subtype avian influenza virus (AIV), poses a serious threat to poultry farming and public health due to its transmissibility and pathogenicity. The PB2 protein is a major component of the viral RNA polymerase complex. It is of great importance to identify the antigenic determinants of the PB2 protein to explore the function of the PB2 protein. In this study, the PB2 sequence of H9N2 subtype AIV, from 1090 to 1689 bp, was cloned and expressed. The recombinant PB2 protein with cutting gel was used to immunize BALB/c mice. After cell fusion, the hybridoma cell lines secreting monoclonal antibodies (mAbs) targeting the PB2 protein were screened by indirect ELISA and western blotting, and the antigenic epitopes of mAbs were identified by constructing truncated overlapping fragments in the PB2 protein of H9N2 subtype AIV. The results showed that three hybridoma cell lines (4B7, 4D10, and 5H1) that stably secreted mAbs specific to the PB2 protein were screened; the heavy chain of 4B7 was IgG2α, those of 4D10 and 5H1 were IgG1, and all three mAbs had kappa light chain. Also, the minimum B-cell epitope recognized was <sup>475</sup>LRGVRVSK<sup>482</sup> and <sup>528</sup>TITYSSPMMW<sup>537</sup>. Homology analysis showed that these two epitopes were conserved among the different subtypes of AIV strains and located on the surface of the PB2 protein. The above findings provide an experimental foundation for further investigation of the function of the PB2 protein and developing monoclonal antibody-based diagnostic kits.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"390-399"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140334589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Avian PathologyPub Date : 2024-10-01Epub Date: 2024-05-24DOI: 10.1080/03079457.2024.2348513
Momtaz A Shahein, Hesham A Sultan, Ali Zanaty, Amany Adel, Zienab Mosaad, Dalia Said, Ahmed Erfan, Mohamed Samy, Abdullah Selim, Karim Selim, Mahmoud M Naguib, Heba Hassan, Osama El Shazly, Zeinab A El-Badiea, Mahmoud K Moawad, Abdelhafez Samir, Mohamed El Shahaby, Eman Farghaly, Samah Eid, Mohamed N Abdelaziz, Mohamed M Hamoud, Osama Mehana, Naglaa M Hagag, Ahmed Samy
{"title":"Emergence of the novel infectious bursal disease virus variant in vaccinated poultry flocks in Egypt.","authors":"Momtaz A Shahein, Hesham A Sultan, Ali Zanaty, Amany Adel, Zienab Mosaad, Dalia Said, Ahmed Erfan, Mohamed Samy, Abdullah Selim, Karim Selim, Mahmoud M Naguib, Heba Hassan, Osama El Shazly, Zeinab A El-Badiea, Mahmoud K Moawad, Abdelhafez Samir, Mohamed El Shahaby, Eman Farghaly, Samah Eid, Mohamed N Abdelaziz, Mohamed M Hamoud, Osama Mehana, Naglaa M Hagag, Ahmed Samy","doi":"10.1080/03079457.2024.2348513","DOIUrl":"10.1080/03079457.2024.2348513","url":null,"abstract":"<p><p>Since the detection of antigenically atypical very virulent Infectious bursal disease viruses (vvIBDV) in Egypt in 1999, the country has been experiencing recurrent outbreaks with high mortality rates and typical gross lesions associated with typical vvIBDV. However, a significant change occurred in 2023, marked by a notable increase in reported subclinical IBDV cases. To evaluate the field situation, samples from 21 farms in 2023 and 18 farms from 2021 and 2022, all of which had experienced IBD outbreaks based on clinical diagnosis, were collected, and subjected to VP2-HVR sequencing. Phylogenetic analysis revealed that all samples collected in 2021 and 2022 clustered with classical virulent strains and vvIBDV. In 2023, one sample clustered with the Egyptian vvIBDV, another with classical virulent IBDV, and the rest with the novel variant IBDV (nVarIBDV) circulating in China. The alignment of deduced amino acid sequences for VP2 showed that all Egyptian classic virulent strains were identical to the Winterfield or Lukert strains, while vvIBDV strains exhibited two out of the three typical residues found in Egyptian vvIBDV, namely Y220F and G254S, but not A321T. Meanwhile, all Egyptian variant strains exhibited typical residues found in nVarIBDV. However, all Egyptian variants showed a mutation at position 321 (321V), which represents the most exposed part of the capsid and is known to have a massive impact on IBDV antigenicity, except for one sample that had 318G instead. This report highlights the emergence of a new variant IBDV in Egypt, clustered with the Chinese new variants, spreading subclinically in broiler farms across a wide geographic area.<b>RESEARCH HIGHLIGHTS</b> New variant IBDV which emerged in Egypt clustered with Chinese nVarIBDV.nVarIBDV spread subclinically across a wide geographic area.Mutation at 321 represents capsid's most exposed part, a defining feature.Antigenically modified vvIBDV still circulating in Egypt with typical lesions.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"419-429"},"PeriodicalIF":2.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141086698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Avian PathologyPub Date : 2024-09-12DOI: 10.1080/03079457.2024.2403414
Klao Runcharoon,Bellanirys Garcia,Breck N Peterson,Meaghan M Young,Margaret E Favro,Nicolle L Barbieri,Doug Waltman,Bridgeth Flores,Emily Dinh,Catherine M Logue
{"title":"Longitudinal Study of Avian Pathogenic Escherichia coli (APEC) serogroups associated with disease in Georgia poultry using molecular serology and virulence gene analysis.","authors":"Klao Runcharoon,Bellanirys Garcia,Breck N Peterson,Meaghan M Young,Margaret E Favro,Nicolle L Barbieri,Doug Waltman,Bridgeth Flores,Emily Dinh,Catherine M Logue","doi":"10.1080/03079457.2024.2403414","DOIUrl":"https://doi.org/10.1080/03079457.2024.2403414","url":null,"abstract":"Avian pathogenic Escherichia coli (APEC) is a significant cause of morbidity, mortality, and production loss to the poultry industry worldwide. Here, we characterized 569 E. coli isolates from avian-diagnosed colibacillosis cases from the state of Georgia, USA. A total of 339 isolates were assigned into 32 serogroups with the majority classifying as O78, O2, O25, O8, O1, O86, O18, and O15. Serogroup O25 was found to link with broilers, while broiler breeders were more often associated with serogroup O1 and pet/ hobby birds with serogroup O8. In addition, some serogroups (O1) were more prevalent in the Summer and Fall. Analysis for virulence-associated genes (VAGs) found 23.20% of isolates did not harbor any genes linked with the APEC pathotype, while ColV plasmid-associated genes (iroN, ompT, hlyF, iss, and aerJ,) were frequently detected among most isolates (with 80 to 96% prevalence) and some of these genes were linked with serogroup. Phylogenetic analysis, classified isolates into phylogenetic groups B2 (27%), G (21%), F (15%), and A (11%). The phylogenetic group B2 isolates also harbored the highest number of VAGs. This study highlights that the current APEC-causing disease in birds in the State of Georgia has identified several emerging serogroups possessing several VAGs that could potentially lead to challenges in colibacillosis control.","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":"14 1","pages":"1-101"},"PeriodicalIF":2.8,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142195017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparative examination of a rapid immunocytochemical test for the detection of highly pathogenic avian influenza virus in domestic birds in field outbreaks.","authors":"Levente Szeredi, Ákos Thuma, Éva Gyuris, Krisztina Ursu, Ádám Bálint, Norbert Solymosi","doi":"10.1080/03079457.2024.2320699","DOIUrl":"10.1080/03079457.2024.2320699","url":null,"abstract":"<p><p>The quantitative real-time reverse polymerase chain reaction (RRT-PCR) is the preferred test method for the diagnosis of avian influenza (AI), but can be performed only in specialized laboratories. Different antigen detection methods for the diagnosis of AI were previously reported to be specific and sensitive in field outbreaks. These tests can be performed in basic countryside labs. Brain smears of domestic birds (<i>n</i> = 105) collected during AI field outbreaks were examined with immunocytochemistry (IC). The results were statistically analysed by comparing IC to brain histology (BH), and immunohistochemistry (IHC), to gross pathological examination (GP) (<i>n</i> = 105), and RRT-PCR (<i>n</i> = 91). AI was diagnosed with RRT-PCR in 66 cases. IC and IHC were positive in 59/66 (90%) and 60/66 (91%) cases, respectively. Lesions suspicious for AI were detected with GP and HP in 66/66 (100%) and 61/66 (92%) cases, respectively. An almost perfect agreement was found between RRT-PCR, IC, IHC, and HP. Substantial agreement was found between IC and GP, between IHC and GP, between HP and GP, and between RRT-PCR and GP. The chromogen-based IC test presented in this study produces durable staining, which can be evaluated using a simple brightfield microscope. The test is rapid (can be completed in 2 h), sensitive (90%), specific (100%), and cost-effective, which makes the method suitable for routine diagnostic tests in AI epidemics.<b>RESEARCH HIGHLIGHTS</b>Avian influenza virus (AIV) antigen detection was examined in field outbreaks.Bird brain smears were tested using immunocytochemistry (IC).IC results strongly correlated with real-time RT-PCR results.The IC method was rapid, specific, sensitive, and cost-effective in AIV field outbreaks.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"285-290"},"PeriodicalIF":2.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139899285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Novel lncRNA 803 related to Marek's disease inhibits apoptosis of DF-1 cells.","authors":"Shuo Han, Shuang Zhao, Haile Ren, Qianqian Jiao, Xianjia Wu, Xinrui Hao, Mingchun Liu, Liping Han, Limei Han","doi":"10.1080/03079457.2024.2316817","DOIUrl":"10.1080/03079457.2024.2316817","url":null,"abstract":"<p><p>Marek's disease (MD) is a neoplastic disease that significantly affects the poultry industry. Long non-coding RNAs (lncRNAs) are crucial regulatory factors in various biological processes, including tumourigenesis. However, the involvement of novel lncRNAs in the course of MD virus (MDV) infection is still underexplored. Here, we present the first comprehensive characterization of differentially expressed lncRNAs in chicken spleen at different stages of MDV infection. A series of differentially expressed lncRNAs was identified at each stage of MDV infection through screening. Notably, our investigation revealed a novel lncRNA, lncRNA 803, which exhibited significant differential expression at different stages of MDV infection and was likely to be associated with the p53 pathway. Further analyses demonstrated that the overexpression of lncRNA 803 positively regulated the expression of p53 and TP53BP1 in DF-1 cells, leading to the inhibition of apoptosis. This is the first study to focus on the lncRNA expression profiles in chicken spleens during MDV pathogenesis. Our findings highlight the potential role of the p53-related novel lncRNA 803 in MD pathogenesis and provide valuable insights for decoding the molecular mechanism of MD pathogenesis involving non-coding RNA.<b>RESEARCH HIGHLIGHTS</b> Differentially expressed lncRNAs in spleens of chickens infected with Marek's disease virus at different stages were identified for the first time.The effects of novel lncRNA 803 on p53 pathway and apoptosis of DF-1 cells were reported for the first time.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"229-241"},"PeriodicalIF":2.5,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139696872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Avian PathologyPub Date : 2024-08-01Epub Date: 2024-04-10DOI: 10.1080/03079457.2024.2334682
Jesper Tessin, Arne Jung, Amanda Silberborth, Karl Rohn, Jochen Schulz, Christian Visscher, Nicole Kemper
{"title":"Detection of <i>Enterococcus cecorum</i> to identify persistently contaminated locations using faecal and environmental samples in broiler houses of clinically healthy flocks.","authors":"Jesper Tessin, Arne Jung, Amanda Silberborth, Karl Rohn, Jochen Schulz, Christian Visscher, Nicole Kemper","doi":"10.1080/03079457.2024.2334682","DOIUrl":"10.1080/03079457.2024.2334682","url":null,"abstract":"<p><p>Worldwide outbreaks make infections with pathogenic strains of <i>Enterococcus cecorum</i> (EC) one of the most important diseases in the broiler industry. Although research has increased knowledge about the pathogen, the transmission is not fully understood. Samples from different locations were collected from two broiler farms in Germany over a total of six production cycles. Samples were collected at days 1, 5, 10, 15, 21, 27, 34, 41 post-hatch and after cleaning and disinfection (C&D). A total of 1017 samples were collected from 25 different locations on the farms. Samples were analysed in the laboratory for EC by quantitative real-time PCR. Overall, 7.5% of the samples were positive. The probabilities for positive and negative samples did not differ between the farms. The number of findings differed significantly between the cycles. Compared to other samples, the chances of detecting EC in faecal samples were significantly higher. Most positive samples were found in the last week of the production periods, indicating an accumulation of EC in the barn environment. After C&D, positive PCR results were obtained in four out of 14 locations. A re-introduction from contaminated environment seemed possible. However, one pooled faecal sample was positive 1 day post-hatch. The locations that showed positive results after C&D and the positive faecal sample 1 day post-hatch indicated the persistence of EC in broiler houses of clinically healthy flocks that could lead to potential horizontal transmission routes. The present study detected potential EC sources and may help to improve hygienic measures to avoid transmissions.<b>RESEARCH HIGHLIGHTS</b>Methodology is suitable to detect EC during production and after C&D.Locations were detected that may serve as a reservoir for EC.Cycles with fewer positive samples were observed.Cleaning and disinfection had a major impact on the detection of EC.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"312-320"},"PeriodicalIF":2.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140206290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Avian PathologyPub Date : 2024-08-01Epub Date: 2024-03-08DOI: 10.1080/03079457.2024.2323029
Dagmara Stępień-Pyśniak, Marta Dec, Tomasz Hauschild, Olimpia Kursa, Agnieszka Marek, Jarosław Wilczyński, Michał Brzeski
{"title":"Case reports involving coinfection with <i>Avibacterium paragallinarum</i> and <i>Ornithobacterium rhinotracheale</i> in broiler chickens and <i>Avibacterium endocarditis</i> in broiler breeding hens in Poland.","authors":"Dagmara Stępień-Pyśniak, Marta Dec, Tomasz Hauschild, Olimpia Kursa, Agnieszka Marek, Jarosław Wilczyński, Michał Brzeski","doi":"10.1080/03079457.2024.2323029","DOIUrl":"10.1080/03079457.2024.2323029","url":null,"abstract":"<p><p><b>ABSTRACT</b>The study describes three clinical cases of infection with <i>Avibacterium</i> spp.. In case no. 1, respiratory clinical signs and high mortality (0.7-4.2% daily; total 21.2%) in Ross 308 broiler chickens were shown to be caused by coinfection with sequence type 9 of <i>O. rhinotracheale</i> presumptive serotype A and <i>A. paragallinarum</i> presumptive serotype B. The identical (pulsed-field gel electrophoresis) restriction pattern (pulsotype) of seven <i>A. paragallinarum</i> isolates indicated that infectious coryza in broilers was caused by the same clone. In cases 2 and 3, sudden increased deaths in Ross 308 broiler breeders (especially males) with lesions in the endocardium (valvular or mural endocarditis) were shown to be caused by <i>A. endocarditis</i>. Among nine antibiotics tested, florfenicol was the only antibiotic to which all <i>A. paragallinarum</i> and <i>O. rhinotracheale</i> isolates were susceptible. Out of the eight antibiotics tested, 11 <i>A. endocarditis</i> isolates from both clinical cases of infective endocarditis were susceptible to penicillin, amoxicillin, doxycycline and florfenicol. The <i>A. endocarditis</i> isolates tested in both clinical cases had different PFGE patterns (pulsotypes), but identical within a case. The causes of infectious coryza and infective endocarditis in the cases presented have not been determined. In the prevention of infectious diseases in large-scale livestock farming, it is very important to follow the rules of biosecurity.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"291-302"},"PeriodicalIF":2.5,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139929854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Avian PathologyPub Date : 2024-08-01Epub Date: 2024-02-26DOI: 10.1080/03079457.2024.2318006
Dénes Grózner, Zsuzsa Kreizinger, Alexa Mitter, Katinka Bekő, Dominika Buni, Áron B Kovács, Enikő Wehmann, Eszter Zsófia Nagy, Ádám Dobos, Ádám Dán, Nikolett Belecz, Karola Költő, Veronika Hrivnák, Lilla Udvari, Dorottya Földi, György Czifra, Márton Kiss, László Spitzmüller, Béla Molnár, Miklós Gyuranecz
{"title":"Evaluating the dynamics and efficacy of a live, attenuated <i>Mycoplasma anserisalpingitidis</i> vaccine candidate under farm conditions.","authors":"Dénes Grózner, Zsuzsa Kreizinger, Alexa Mitter, Katinka Bekő, Dominika Buni, Áron B Kovács, Enikő Wehmann, Eszter Zsófia Nagy, Ádám Dobos, Ádám Dán, Nikolett Belecz, Karola Költő, Veronika Hrivnák, Lilla Udvari, Dorottya Földi, György Czifra, Márton Kiss, László Spitzmüller, Béla Molnár, Miklós Gyuranecz","doi":"10.1080/03079457.2024.2318006","DOIUrl":"10.1080/03079457.2024.2318006","url":null,"abstract":"<p><p>The aim of the present study was to monitor the dynamics and to measure the safety and efficacy of a live, attenuated, thermosensitive <i>Mycoplasma anserisalpingitidis</i> vaccine candidate, namely MA271, in geese breeder flocks under field conditions. Two rearing flocks were vaccinated with MA271 at 4 weeks of age and boosted at 24 weeks of age by cloaca inoculation (1 ml) and eye-dropping (60 µl). The geese then were transported to multi-aged breeding farms. Two breeding flocks served as controls. Colonization of the cloaca by MA271 showed 75% maximum prevalence between 4 and 6 weeks after the first vaccination. Then the prevalence decreased to 25% until the cooler, humid fall months which coincided with the booster vaccination. Boosting raised cloacal colonization to 100%. No clinical signs were observed in the vaccinated birds. After transportation to five multi-aged breeding farms, the wild-type strain appeared as well as MA271 in three flocks. In one flock, the wild-type strain completely displaced MA271, while in one flock only MA271 was detected. Only wild-type strains were detected in the control flocks; however, due to an HPAI outbreak, both flocks were exterminated before the end of the study. Based on the available data, the median percentage of infertile eggs was 3.7-5.1% in the MA271 vaccinated flocks, and 7.7% in the non-vaccinated flock. In conclusion, MA271 can colonize the cloaca of geese under field conditions. MA271 proved to be safe and presumably protects against <i>M. anserisalpingitidis-</i>induced reproduction losses.</p>","PeriodicalId":8788,"journal":{"name":"Avian Pathology","volume":" ","pages":"257-263"},"PeriodicalIF":2.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139728840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}