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Infectious bronchitis virus played a primary role or a synergistic effect in the mortality of chickens that succumbed to other infectious diseases. The sequences of IBV detected in 22 birds were analyzed, and 14 strains were most similar to CA1737. One strain each matched Conn46, Cal99, and ArkDPI, and the remaining five did not have a substantial match to any available reference strains. The findings in this study indicate that small flocks can be reservoirs of IBV and might facilitate evolution of new variants as well as reversion of attenuated strains to virulence.Currently, the poultry industry worldwide is facing an emerging trend of fowl adenovirus (FAdV)-associated diseases with a significant economic impact, especially in meat-type chickens. Vertical transmission is an important feature of all FAdVs; hence, preventive measures mostly revolve around breeding stocks. However, knowledge about temporal development of FAdV infections in modern commercial settings is rare or even nonexistent. In the present study, longitudinal monitoring for FAdV was conducted in broiler breeder flocks located in a confined geographical region with intensive poultry production in Iran. For this, the antibody status of birds from 4 to 32 wk of age was monitored with a commercial FAdV-ELISA and virus neutralization test (VNT). In parallel, fecal shedding of FAdV was determined at the peak of egg production with real-time PCR and virus isolation. Overall, the commercial ELISA showed seroconversion of flocks before onset of production. VNT resolved in detail infection patterns of individualb, one outbreak of adenoviral gizzard erosion related to FAdV-1, and no evidence of hepatitis-hydropericardium syndrome suggest that identical serotypes are maintained in the local poultry industry.Trueperella pyogenes is an opportunistic Gram-positive bacterium that induces purulent lesions and abscesses in cattle, small ruminants, and swine. In birds, T. pyogenes infections have been linked to lameness and osteomyelitis in turkeys (Phasianidae) and hepatic fibriscess in turkeys and pigeons (Columbidae). An 18-mo-old backyard rooster with a history of progressive emaciation was submitted to the California Animal Health and Food Safety (CAHFS) laboratory system. At necropsy, unusual numerous miliary granulomas were identified, primarily in the spleen, but granulomas were also observed in air sacs and lungs. Microscopically, few to moderate numbers of granulomas with giant cells were observed in the spleen, lung, air sacs, and crop composed of necrosis and mixed inflammatory cell inflammation including multinucleated giant cells, fibrin deposition, and fibrosis. Trueperella pyogenes was isolated from the air sacs and trachea. Avibacterium paragallinarum PCR was positive from the tracheal swab. A retrospective analysis of CAHFS data on T. pyogenes between 2000 and 2020 identified 24 cases in avian species chickens (Gallus gallus domesticus; 16/24), turkeys (5/24), Pekin duck (Anas platyrhynchos domesticus; 1/24), parrot (Psittaciformes; 1/24), and pheasant (Phasianidae; 1/24). Although T. pyogenes infection in birds is rare, the clinical signs and gross lesions might be indistinguishable from avian mycobacteriosis in some cases and should be considered in the differential diagnosis.The present report describes outbreaks of Streptococcus gallolyticus subsp. pasteurianus in young geese flocks in Austria. The flocks, comprising 160-1450 goslings of 2-3 wk of age, experienced increased mortalities The clinical signs were characterized by severe central nervous symptoms, namely leg paddling and torticollis. The postmortem investigation revealed hepatitis, splenitis, and a low amount of liquid fluid in the coelomic cavity. Livers were of fragile texture, with white necrotic areas. The latter were also found in spleens. No macroscopic lesions were seen in brains. Bacteriologic investigation followed by bacterial identification by matrix-assisted laser desorption time-of-flight mass spectrometry and phylogenetic analysis of the partial 16S rRNA region revealed the presence in heart, liver, spleen, and brain of S. gallolyticus subsp. pasteurianus. Histologic investigation revealed multifocal necrosis in liver and spleen samples together with infiltration of mononuclear cells and heterophilic granulocytes. Furthermore, in the lesions, coccoid bacteria could be identified. No histopathologic changes were observed in brain samples from goslings, except in one bird in which accumulation of coccoid bacteria in blood vessels of the brain samples was present. Antibiotic sensitivity tests revealed identical profiles for all strains, which were susceptible to penicillins, cephalosporins, chloramphenicol, imipenem, and tylosin. However, resistance was found against quinolones, aminoglycosides, tetracycline, and trimethoprim-sulfamethoxazole, which are commonly used to treat infections with gram-positive bacteria.The present report describes an outbreak of Pullorum disease in a young layer parent stock in Austria. The flock, which comprised 14,220 Lohmann brown layer chickens, experienced high mortality from the first week of life, reaching a total of 1905 chickens in the fifth week, when the flock was depopulated. Clinical signs included uneven size of the chicks, pasty vents, apathy, and diminished water and feed intake, with some birds presenting central nervous system signs such as tremors and torticollis. The postmortem investigation of 43 birds, of ages 1 to 4 weeks, revealed retained yolk sacs filled with caseous exudate, purulent airsacculitis, hepatitis with whitish pinpoint coalescing necrotic foci, splenitis with splenomegaly, hemorrhagic-mucoid enteritis in the small intestine, fibrinous typhlitis, nephromegaly, and urate deposits in the ureters and cloaca. Inflammation and/or necrosis were identified in liver, spleen, kidney, small intestine, and heart by histopathology. However, no histopathologic lesions were observed in the brain. Salmonella enterica was isolated from heart, liver, spleen, and brain in pure culture. Group-specific serotyping determined the presence of group D, with S. enterica subspecies enterica serovar Gallinarum being confirmed based on the Kauffmann-White scheme. A duplex PCR further identified S. enterica subspecies enterica serovar Gallinarum biovar Pullorum as the responsible agent for the outbreak. Subsequently, the grandparent flocks, from which the affected flock originated, were tested and found to be negative for Salmonella Pullorum, with no other progenies from the same grandparents developing disease. Although the source of the pathogen could not be identified, such findings highlight the importance of "old" pathogens such as Salmonella Pullorum causing sudden high mortality in chicks, even in a highly controlled environment.With growing cross-disciplinary collaboration among researchers, it is increasingly important to record detailed methodology to prevent the repetition of preliminary experiments. The purpose of this paper is to explain the development of a coccidiosis challenge model for the investigation of dietary interventions to coccidiosis in broiler chickens. The objectives are to select a dose of mixed species coccidial vaccine and evaluate the suitability (ability to produce a consistent, marked change) of selected response variables important to nutritional studies at different times postinfection (PI). Coccivac-B and Coccivac-B52 (Merck Animal Health) were evaluated as the source of coccidia in three trials. Trials 1 and 2 were randomized complete block designs with four doses (0, 10, 20, or 30 times (×) label dose) of Coccivac-B administered to 12 replicate cages of six birds by repeater pipette (Trial 1) or gavaging needle (Trial 2). Trial 3 used a completely randomized design with 0× or 30× label dose of Coccivacpported by oocyst count scores. At 7 days PI there was no correlation between midgut gross lesion score and midgut oocyst count score (r = 0.06, P = 0.705), but cecal scores were weakly correlated (r = 0.55, P less then 0.001). Administering coccidia via repeater pipette (Trial 1) resulted in respiratory distress in some birds, while use of the gavaging needle (Trials 2 and 3) successfully induced intestinal damage in chickens without resulting in coccidia related mortality. Thirty times the label dose at 7 days PI resulted in the greatest number of response variables that produced a consistent, marked change. Therefore, consideration should be given to these conditions when designing future coccidiosis challenge models using vaccines as a source of coccidia.Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is an important foodborne zoonosis affecting a wide range of hosts, including birds. This study investigated the seroconversion, feed conversion rate, weight gain, and parasite tissue tropism as a function of parasite dose and virulence in turkeys. Twenty-five 4-wk-old female domestic turkeys (Meleagris gallapavo) were intraperitoneally infected with two different strains and two doses (105 and 108 tachyzoites/ml) of T. gondii tachyzoites, resulting in four treatment groups. A fifth group of 10 additional birds was intraperitoneally injected with sterile phosphate-buffered saline as a negative control. All birds remained subclinical except for three birds in the two high-dose groups (108 tachyzoites/ml). Survival rate was 88% (22/25). A 92% seroconversion rate was detected in T. gondii-infected birds using a modified agglutination test. Antibody titers as well as weight gain were related to the dose and strain of T. gondii used. Feed conversion rate was higher in the high-dose groups compared with low-dose and control groups, while weight gain was significantly lower at 14 days postinfection in the group infected with 108 tachyzoites/ml of virulent T. gondii strain. Gross lesions were detected in the pancreas and lungs of only one bird, and histopathologic findings varied depending on strain and dose. The organs that most frequently contained T. gondii DNA as detected by quantitative PCR were the brain and the heart, followed by the bursa of Fabricius and the lungs. This study confirmed that turkeys can be infected with T. gondii, and turkeys can show signs of infection when exposed to high doses. Given the increased practice of outdoor-raised livestock and wildlife consumption, continual experimental infection of T. gondii in wild and domestic animals should be pursued.Necrotic enteritis (NE) is a common disease that causes great economic loss to the broiler industry due to mortality and reduced performance. Although Clostridium perfringens (CP) is a necessary component of this disease, coccidia species are a well-defined predisposing factor that exacerbates the condition. Different Eimeria species have been reported to influence NE to different degrees. In a pair of experiments, six different Eimeria species were evaluated in the presence and absence of C. perfringens. Male broiler chicks were housed in battery cages for the duration of both experiments. Feed conversion, body weight gain, and NE mortality were reported in both experiments. Experiment 1 challenged birds with E. maxima, E. acervulina, E. tenella, E. necatrix, and E. find protocol brunetti at day 13 and subsequently inoculated birds with CP on days 18, 19, and 20. In the second experiment, E. maxima, E. acervulina, E. tenella, and E. praecox were inoculated on day 15 and challenged with CP on days 17, 18, 19, 20, 21, and 22 of the experiment.

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