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ABSTRACT Avian mycoplasmosis is a disease of significant economic impact, potentially leading to restrictions on the international trade of poultry products. Mycoplasma synoviae (MS) and Mycoplasma gallisepticum (MG) are well-established as pathogenic, while Mycoplasma gallinaceum (Mgc) is considered commensal. Nevertheless, the latter can exacerbate clinical conditions in cases of co-infections with other pathogens. Due to the slow growth rates of MS and MG, they are susceptible to being outpaced by fast growing mycoplasmas, thereby complicating cultivation, and potentially yielding false-negative results. Thus, this study aimed to report a mixed infection of Mgc and MS in commercial laying hens and the compromised isolation of MS caused by this non-pathogenic mycoplasma. Twenty tracheal samples from chickens were collected, subjected to PCR, and cultured in a modified Frey’s medium. Samples displaying colonies compatible with mycoplasmas underwent three passages to obtain pure cultures. PCR-positive samples for the Mycoplasma spp., and negative ones for MS and MG, were subsequently subjected to DNA sequencing. All clinical samples tested via PCR were positive for MS (20/20) and negative for MG (0/20). During isolation, only five samples exhibited colonies with characteristic mycoplasma growth. However, PCR analysis of these cultures produced negative results for MS and MG, but were positive for Mycoplasma spp. DNA sequencing confirmed that all isolated strains were Mgc. Mgc displayed rapid growth, posing challenges to obtaining MS strains for isolation. The coexistence of MS and Mgc in the respiratory tract of commercial laying hens has the potential of inducing a synergistic effect on respiratory manifestations.

Background: The emergence of new variants of SARS-CoV-2 has led to the administration of different booster vaccines to mitigate COVID-19. Vaccines with adenoviral vectors have been rarely associated with vaccine-induced immune thrombotic thrombocytopenia (VITT)., Objectives: This study aimed to describe 15 cases of VITT after the third and fourth doses of the COVID-19 vaccine in Brazil., Methods: Cases were reported after all kinds of anti-SARS-CoV-2 booster vaccinations between October 17, 2021, and September 4, 2022., Results: Of the 26 suspected cases, 15 cases of VITT were analyzed. Of these, 10 were classified as definite VITT, 2 as probable, 1 as possible, and 2 as unlikely. The estimated frequency of definite, probable, or possible VITT was 0.33 cases per million. Cases were assigned to ChAdOx1 (13 cases), Ad26.COV2.S (1 case), and BNT162b2 (1 case). None of the patients received an adenoviral vaccine as a primary vaccination. The average age of participants was 34 years, and symptoms usually appeared 8 days after vaccination. Headache was the most common symptom, and cerebral veins were the most affected thrombotic site. The overall mortality risk was 53%. Anti-platelet factor 4 enzyme-linked immunosorbent assay serology was positive in 11 out of 15 patients (73.3%), negative in 2 (13.3%), and missing in 2 (13.3%)., Conclusion: The study confirms that VITT is linked to the first exposure to adenoviral vector vaccines. Since January 2023, Brazil has recommended preferably COVID-19 messenger RNA vaccines for individuals aged 18 to 39 years. We suggest that, in the current disease scenario, COVID-19 adenovirus vaccines should not be the first choice for individuals aged <50 years who have not received a previous dose of this type of vaccine., (© 2023 The Author(s).)

Mycoplasma gallisepticum causes coughing, ocular and nasal discharge, reduction in feed intake, lower and uneven growth, decline in egg production and quality, and increase in mortality. Among the attenuated vaccination strains, MGF can reduce clinical signs and lesions in layer hens, stimulate immune responses of cellular and humoral basis, act as an instrument of competitive exclusion in relation to field strains, and reduce the use of antimicrobials. This study aimed to investigate the effects of attenuated MG F-strain vaccination on egg quality in 3 groups of 30 hens each, being one control and 2 vaccinated. Vaccination was applied by ocular route at 8 and 12 wk of age. Comparisons were made among unvaccinated hens; vaccinated at 8 wk of age; and vaccinated at 8 and 12 wk of age. There were no statistical differences in eggshell thickness and weight among groups. Eggs from twice vaccinated birds yielded a Haugh unit significantly lower than the other groups without affecting egg classification. There was no significant difference in ELISA results between the vaccinated groups., (© 2016 Poultry Science Association Inc.)

The production of chicken feet is primarily intended for foreign markets, and there is still no specific legislation in Brazil that determines the quality standard of these products. The bacteriological quality of chicken feet was evaluated as a product for human consumption at different steps of the technological processes. Eighty broiler feet from 20 lots at 4 steps of processing were collected for quantitative analysis, total count of aerobic mesophilic bacteria, and determining the most probable number of coliforms and fecal coliforms. Thirty-eight pools of 15 broiler feet each from 19 lots were used for qualitative analysis and the isolation of Salmonella enterica spp. and Escherichia coli O157:H7. Escherichia coli O157:H7 was not found in any of the samples. Salmonella spp. were isolated in 68% (13/19) of the lots. The Salmonella Schwarzengrund serotype was found in 12 of the 13 lots of positive samples and the Salmonella Anatum and Salmonella Corvallis serotypes were identified in the remaining lot. Processing is effective in reducing contamination by mesophilic bacteria, coliforms, and Salmonella spp. in these products. This work constitutes the first study in Brazil on microbiological quality of chicken feet.

Monolithic catalysts are widely used as structured catalysts, especially in the abatement of pollutants. Probing what happens inside these monoliths during operation is, therefore, vital for modelling and prediction of the catalyst behavior. SpaciMS is a spatially resolved capillary-inlet mass spectroscopy system allowing for the generation of spatially resolved maps of the reactions within monoliths. In this study SpaciMS results combined with 3D CFD modelling demonstrate that SpaciMS is a highly sensitive and minimally invasive technique that can provide reaction maps as well as catalytic temporal behavior. Herein we illustrate this by examining kinetic oscillations during a CO oxidation reaction over a Pt/Rh on alumina catalyst supported on a cordierite monolith. These oscillations were only observed within the monolith by SpaciMS between 30 and 90% CO conversion. Equivalent experiments performed in a plug-flow reactor using this catalyst in a crushed form over a similar range of reaction conditions did not display any oscillations demonstrating the importance of intra monolith analysis. This work demonstrates that the SpaciMS offers an accurate and comprehensive picture of structured catalysts under operation.