Avian diseases最新文献

{"title":"<i>Listeria monocytogenes</i> Infection in a Chicken (<i>Gallus gallus domesticus</i>): Pathology and Diagnostic Challenges.","authors":"Emily Frye, Megan Lighty, Maurice Byukusenge, Philma Glora Muthuraj, Kayla Niel","doi":"10.1637/aviandiseases-D-25-00089","DOIUrl":"10.1637/aviandiseases-D-25-00089","url":null,"abstract":"<p><p>This case report details listeriosis in a chicken from a public botanic garden and the ancillary testing required to confirm <i>Listeria monocytogenes.</i> A 6-mo-old female Barred Plymouth Rock chicken, found deceased within its flock at a public botanic garden, was submitted to The Pennsylvania State University Animal Diagnostic Laboratory for postmortem examination. The clinical history included bloody feces, weight loss, and pallor prior to death. On postmortem examination, the chicken was emaciated with vent fecal staining. Gross lesions suggested bacterial septicemia, including necrotic fibrinous hepatitis, peritonitis, myocarditis, and pancreatitis. The heart was rounded, with pericardial effusion and a focal, dry, white bulging area around the left ventricle. Ulceration of the gizzard mucosa, severe, focal, unilateral cecal dilation, and ulceration with hemorrhage and necrosis were supportive of gastroenteritis and typhlitis. Differential diagnoses included lymphoid neoplasia, chronic coccidial or bacterial enteritis or typhlitis, bacterial septicemia, and mycobacteriosis. On histology, major findings included granulomatous myocarditis and endocarditis, as well as transmural coccidial enteritis and typhlitis. Preliminary results from ancillary testing confirmed severe coccidiosis and bacterial myocarditis. Although matrix-assisted laser desorption-ionization time of flight (MALDI-TOF) mass spectrometry identified nonpathogenic <i>Listeria innocua</i>, the severity of the heart lesions and the hemolysis observed on culture suggested a pathogenic species. Whole-genome sequencing confirmed the presence of <i>L. monocytogenes,</i> rather than the <i>L. innocua</i> incorrectly identified by MALDI-TOF. This case highlights the presentation of listeriosis in a chicken, the importance of confirmatory testing in the face of equivocal results, and potential disease risks in public spaces shared with avian species.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 2","pages":"240-248"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148430974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel IBV Lineage within Genotype GVII (GVII-2) Representing a Unique Serotype Circulating in Chicken Flocks in China.","authors":"Bing Wang, Xiaona Zhang, Zongxi Han, Huixin Li, Junfeng Sun, Shengwang Liu","doi":"10.1637/aviandiseases-D-25-00027","DOIUrl":"https://doi.org/10.1637/aviandiseases-D-25-00027","url":null,"abstract":"<p><p>In the present study, we report the detection of a novel infectious bronchitis virus lineage within genotypes GVII (GVII-2) in commercial flocks in China since 2008. Virus strains within this lineage have been isolated from different geographic regions in China. S1 genes of these viruses have an intralineage divergence of 0.2%-4.4% nucleotides and 0.1%-7.5% amino acids. The pairwise distances of nucleotide and amino acid sequences based on the S1 subunit between GVII-2 and the closest GVII-1 were 28.3% -28.8% and 28.1%-28.9%, respectively. Complete genomic sequence analysis of the first detected strain, ck/CH/LAH/08I (LAH/08I), suggested that it is derived from recombination events with a genomic backbone of the GI-19 ck/CH/LGS/08I-like strain and distinct S, 3a, and 5a genes. The GVII-2 strain represents a unique serotype that differs from the GVII-1 I0636/16 strain in the same genotype and its deduced parental virus GI-19 I0305/19. Strain LAH/08I not only showed strong tissue tropism in the kidneys of SPF chickens but also exhibited high replication capacities in the trachea, kidney, digestive tract, and immune system of infected chickens, attributed to its pathogenicity in SPF chickens. Strain LAH/08I also showed tropism in the oviducts and the ability to induce cystic oviduct formation in adult chickens after infection in baby chicks.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 2","pages":"174-182"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148431630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Marek's Disease in France: Ten Cases of Central Nervous System Syndromes.","authors":"Matthieu Pinson, Manuela Crispo, Lilou Bortot, Olivier Albaric, Benoit Sraka, Charles Facon, Guillaume Perreul, Thomas Delquigny, Stéphane Lemière, Catherine Belloc, Jean-Luc Guérin","doi":"10.1637/aviandiseases-D-25-00077","DOIUrl":"10.1637/aviandiseases-D-25-00077","url":null,"abstract":"<p><p>Between 2017 and 2019, 10 broiler flocks, with birds exhibiting neck paralysis, nervous tics, and torticollis, were submitted for necropsy and additional tests. These neurologic signs were mostly observed in certified, nonvaccinated broilers (8 of 10), ranging between 45 and 56 days of age. No specific lesions were described at macroscopic examination. Histopathology revealed moderate to severe lymphocytic infiltration of the central nervous system (CNS). In addition, peripheral nerves and visceral organs were commonly affected, although less severely. Immunohistochemistry identified the infiltrating lymphocytes as CD3⁺ T cells, and Marek's disease (MD) virus was detected by real-time PCR in brain formalin-fixed and paraffin-embedded samples in all flocks. In conclusion, MD is still a concern in France. The occurrence of MD CNS syndromes should be considered in commercial broilers starting from 6 wk of age because these conditions could compromise the health and welfare of affected birds. Poultry veterinarians should be aware of this atypical form of MD to ensure proper diagnosis and assess the impact of the disease, especially in nonvaccinated chicken flocks.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 2","pages":"219-223"},"PeriodicalIF":1.3,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148431713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating Acute-Phase Proteins in Feces of Broiler Chickens Undergoing Necrotic Enteritis: A Potential Tool for Assessment and Monitoring.","authors":"Mahmoud A Mahmoud, Vinicius Buiatte, Craig R Baumrucker, Dervan Bryan, Monika Proszkowiec-Weglarz, Katarzyna Miska, Mark Jenkins, Christopher C Chadwick, Alberto Gino Lorenzoni","doi":"10.1637/aviandiseases-D-24-00096","DOIUrl":"10.1637/aviandiseases-D-24-00096","url":null,"abstract":"<p><p>Necrotic enteritis (NE) is a prevalent bacterial disease in the broiler industry caused by <i>Clostridium perfringens</i>. Current monitoring and diagnostics for NE rely on invasive necropsy and subjective lesion scoring. This study introduces fecal acute-phase proteins (APPs) as novel, noninvasive biomarkers for NE, an understudied approach offering objective, scalable monitoring in poultry health. APPs, secreted by the liver and innate immune cells during inflammation and injury, can offer potential insights into disease development. A total of 276 Ross 308 male broilers were divided into four treatments: negative control (NC; uninfected birds fed a grower corn-soybean-based diet); positive control (PC; uninfected birds fed a diet containing wheat, fish meal, and lard referred to here as the proinflammatory diet); coccidiosis (cocci; birds infected with <i>Eimeria maxima</i> fed a proinflammatory diet); and NE (birds coinfected with <i>E. maxima</i> and <i>C. perfringens</i> fed a proinflammatory diet). On Day 21, birds from all treatments were randomly selected and euthanized to collect colon content and evaluate lesion scores, and 64 samples were selected for APP fecal evaluation. Proteins were extracted by using NP-40 lysis buffer, and commercial sandwich ELISAs were conducted to measure the concentrations of the APPs. Data were analyzed using one-way ANOVA, the Tukey test was used to compare means among treatments and groups, and significance was declared when <i>P</i> ≤ 0.05. Calprotectin (MRP-126) concentrations increased about fivefold from NC to PC (<i>P</i> < 0.0001), ∼120-fold from NC to cocci (<i>P</i> < 0.0001), and ∼320-fold from NC to NE (<i>P</i> < 0.0001). The C-reactive protein (CRP) increased about twofold from NC to PC (<i>P</i> = 0.0366), ∼10-fold from NC to NE scores 2-3 (<i>P</i> < 0.0001), and ∼100-fold from NC to NE scores 4-5 (<i>P</i> < 0.0001). These findings underscore the potential of MRP-126 and CRP as fecal biomarkers for screening and detecting inflammation associated with NE in broiler chickens.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"32-41"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147680107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Congenital Cervical Vertebral Malformations and Recurrent Bacterial Infections in Chickens Associated with <i>In Ovo</i> Vaccination Equipment Malfunction.","authors":"Anaïs Fournier-Leclaire, Annie Borduas, Yasmine Boumati, Sonia Chénier","doi":"10.1637/aviandiseases-D-25-00056","DOIUrl":"10.1637/aviandiseases-D-25-00056","url":null,"abstract":"<p><p><i>In ovo</i> vaccination is an effective method of immunization that allows protection early in the life of the chick but requires precision during the administration. This present report describes an occurrence of cervical vertebral malformations in broiler chicks that coincide with mechanical failure of an <i>in ovo</i> vaccination system, in the absence of other detected infectious, nutritional, or toxic etiologies. Cervical scoliosis was observed in 2%-8% of chicks at hatch or within days post hatch in the affected flock, which all came from the same hatchery. Gross and histologic examination of eleven 30-day-old chickens revealed a cervical vertebral misalignment and fusion of the articular cartilage of adjacent vertebrae, with spinal cord compression, without evidence of inflammation. It is hypothesized that a malfunctioning <i>in ovo</i> vaccine injector with a bent needle might have caused mechanical trauma during the injection at day 18 of incubation, possibly contributing to the lesions observed in the chickens. Recurrent <i>Enterococcus faecalis</i> and <i>Escherichia coli</i> infections were also recorded in young chicks, a problem that persisted during the lifespan of the flock, possibly induced by compromised hygiene from the defective injector. These findings indicate that <i>in ovo</i> vaccination equipment malfunction could represent an underrecognized contributing factor to vertebral deformities in chicks.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"140-145"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147679903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>Clostridium septicum</i> Alpha Toxin-Based Recombinant Subunit Vaccine Protects Broiler Chickens Against Clostridial Dermatitis.","authors":"Carissa Gaghan, Becky Tran, Abigail Armwood, Anil J Thachil, Rodolphe Barrangou, Sarah O'Flaherty, Raveendra R Kulkarni","doi":"10.1637/aviandiseases-D-25-00099","DOIUrl":"10.1637/aviandiseases-D-25-00099","url":null,"abstract":"<p><p>Clostridial dermatitis (CD), caused by <i>Clostridium septicum</i>, is an economically important disease of broiler chickens, specifically in flocks raised without antibiotics. Our previous work in turkeys identified a nontoxic domain no. 2 of <i>C. septicum</i> alpha-toxin (ntATX-D2) as a protective vaccine antigen. In the present study, we used a prime-boost immunization regimen to vaccinate broiler chickens subcutaneously with recombinant ntATX-D2 protein followed by a challenge with virulent <i>C. septicum</i> to assess protective immunity. Immunization led to clinical protection, as determined by a significant increase in the body weight gain and a reduction in the gross and histopathological lesions in the skin, subcutis, and skeletal muscle of immunized chickens compared to the unimmunized group. Furthermore, immunological investigation of protective immunity in immunized birds when compared to the unimmunized control group revealed 1) higher levels of antigen-specific serum IgY antibodies, 2) modulation of inflammatory responses in the skin and muscle of immunized chickens, as indicated by transcriptional downregulation of proinflammatory cytokine (IL-1β, IL-6, and IFNγ) and upregulation of anti-inflammatory cytokine (IL-10 and TGFβ) genes, and 3) increased γδ T cell, B cell, and activated T-cell frequencies in the spleen and peripheral blood of immunized birds. Collectively, our findings indicated that ntATX-D2 vaccination of broiler chickens can provide protection against <i>C. septicum-</i>induced CD and that the mechanisms of protection seem to operate through anti-ATX antibodies coupled with modulation of local and systemic inflammatory as well as cellular immune responses.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"69-81"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147679866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the Efficacy of Different Vaccination Programs Using Two Live <i>Salmonella</i> Vaccines Against <i>Salmonella</i> Enteritidis, <i>Salmonella</i> Typhimurium, and <i>Salmonella</i> Gallinarum in Brown Layer Hens.","authors":"Rafael Casarin Penha Filho, Jaime Sarabia, Luiz Sesti, Pascal Paulet","doi":"10.1637/aviandiseases-D-25-00037","DOIUrl":"10.1637/aviandiseases-D-25-00037","url":null,"abstract":"<p><p>Attenuated live <i>Salmonella</i> vaccines are available for controlling this pathogen in poultry. Due to the wide variety of serovars, cross-protection is a matter of debate. This study evaluated five different vaccination programs combining two live vaccines, with focus on cross-protection against challenges with <i>Salmonella enterica</i> serovar Enteritidis (SE), <i>Salmonella enterica</i> serovar Gallinarum biovar Gallinarum (SG), and <i>Salmonella enterica</i> serovar Typhimurium (ST) strains. Vaccination with a SG9R live vaccine in combination with an attenuated SE strain showed the highest levels of protection against all three serovars. Vaccination with the attenuated SE vaccine alone significantly reduced the systemic infection, as evidenced by the complete absence of SE in spleen and liver samples at 7 and 10 days post challenge, and by up to a 2-log reduction of ST in spleen. Unvaccinated chickens exhibited higher fecal shedding of SE and ST. Challenge with pathogenic SG resulted in up to 87.5% mortality in unvaccinated chickens and 42% mortality in birds vaccinated only with the SE vaccine. In contrast, no mortality occurred in groups vaccinated with SG9R, whether administered alone or in combination with SE vaccine. All vaccinated birds showed reduced degeneration of internal organs and were able to mount a timely cellular and humoral immune response, mitigating the impact of fowl typhoid. The use of two different vaccine strains in the same program had no deleterious effects; on the contrary, it contributed to complementary immune responses, enhancing overall protection.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"57-68"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147680048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Note from Editor.","authors":"Randall Singer","doi":"10.1637/0005-2086-70.1.1","DOIUrl":"https://doi.org/10.1637/0005-2086-70.1.1","url":null,"abstract":"","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"1"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147680087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of Quercetin and Thyme Oil Effect on Oxidative Stress Biomarkers and mRNA Expressions of Interleukin 6, 2, and 16 During <i>Eimeria tenella</i> Infection.","authors":"Rania A Mohamed, Haytham A Ali, Gamal A Salem, Ashraf Hussein","doi":"10.1637/aviandiseases-D-25-00048","DOIUrl":"10.1637/aviandiseases-D-25-00048","url":null,"abstract":"<p><p>Coccidiosis is a protozoan disease that causes serious economic losses annually worldwide. This study evaluated thyme oil and quercetin as natural anticoccidial treatments in broiler chickens experimentally infected with <i>Eimeria tenella</i>. In total, 450 one-day-old Hubbard broiler chicks were allocated into 10 groups. On the eighth day of age, five groups remained uninfected: a negative control group (-ve) and early-treated and late-treated groups treated with thyme oil or quercetin. The other five groups were infected with <i>E. tenella</i>: a positive control group (+ve) and early-treated and late-treated groups treated with thyme oil or quercetin. The clinical signs, parasitologic findings, oxidative stress biomarkers, and the relative expressions of interleukins 2, 6, and 16 were evaluated on the sixth, 11th, and 16th days postinfection (dpi). The infection induced bloody diarrhea, weight loss, and high lesion scores in +ve controls, while the infected, thymol-treated (ITE) group yielded the best clinical recovery, lowest lesion scores, and highest weight gain among infected groups. Oocyst shedding peaked at 8 dpi but was significantly reduced in early-treated groups, particularly ITE. Oxidative stress biomarkers and interleukin relative expressions were significantly altered, with early treatment improving antioxidant status and modulating immune responses. In conclusion, the results recommend the early administration of either thyme oil or quercetin to improve the productivity, oxidative stress, and birds' immune response against <i>Eimeria</i> infection.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"2-11"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147679924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation Between Avian Pathogenic <i>Clostridium perfringens</i> Spore Load and Occurrence of Necrotic Enteritis on Broiler Chicken Farms.","authors":"Sydney R Kinstler, Margie D Lee, Eric A Wong, Joel Cline, John J Maurer","doi":"10.1637/aviandiseases-D-25-00080","DOIUrl":"10.1637/aviandiseases-D-25-00080","url":null,"abstract":"<p><p>Necrotic enteritis (NE) is a significant intestinal disease in poultry caused by the spore-forming, obligate anaerobe <i>Clostridium perfringens</i>. Historically, antimicrobials have controlled NE but growing concerns over antibiotic resistance have led to reduced use, resulting in disease resurgence. <i>Clostridium perfringens</i> spores persist in poultry environments, and their accumulation is believed to contribute to NE outbreaks. However, tools to assess spore load and predict outbreak risk are limited. To address this, a selective egg yolk agar medium was developed using potassium chlorate to inhibit aerobic bacteria, combined with heat treatment to enumerate <i>C. perfringens</i> spores in poultry litter. Matrix-assisted laser desorption-ionization time of flight mass spectrometry confirmed that 80% of lecithinase-positive colonies on chlorate-supplemented agar were <i>C. perfringens</i>. When comparing reinforced <i>Clostridium</i> agar and <i>Clostridium perfringens</i> agar (CPA) as bases, chlorate did not significantly reduce lecithinase-positive aerobes. Ninety-nine percent of lecithinase-positive black colonies on CPA were strict anaerobes, and 85% were confirmed as <i>C. perfringens</i> by PCR. A significant correlation (χ² test; <i>P</i> < 0.05) was observed between spore abundance in litter and a farm's NE history. However, spore abundance did not correlate with increased sporulation efficiency in <i>C. perfringens</i> isolates (<i>P</i> = 0.86). Notably, the presence of <i>netB</i>-positive <i>C. perfringens</i> was strongly associated with prior NE outbreaks (<i>P</i> < 0.01). This study demonstrated CPA-based egg yolk agar as an effective diagnostic medium for detecting <i>C. perfringens</i> in poultry litter.</p>","PeriodicalId":516846,"journal":{"name":"Avian diseases","volume":"70 1","pages":"124-132"},"PeriodicalIF":1.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147679934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}