In commercial layer poultry farming, molt induction is an important tool used by egg producers to prolong the production cycle of laying hens. Conven

Clostridium perfringens is the etiological agent of NE, a disease that greatly affects the poultry industry. Experiments on the induction of NE are difficult to carry out, as it is a multifactorial disease, and thus different predisposing factors have been used. This study evaluated the effect of the Gumboro disease vaccine virus vaccine (IBDV-vac) associated or not with infection by Eimeria spp. in broilers, as a predisposing factor for NE. Broilers (n = 99) were divided into groups (11) challenged with IBDV-vac, Eimeria spp. CP type G (CP13, CP14 and CP03) or both. The macroscopic evaluation revealed that the highest average (3.45) of injury occurred for the CP13 + IBDV-vac group. The microscopic analysis showed that Eimeria spp. increased the population of intraepithelial lymphocytes and reduced the villus/crypt ratio in duodenum and jejunum when associated with CP13 or CP14. There was a synergistic effect between the CP strain used and the predisposing factors; nevertheless, it was not clear which was the most effective predisposing factor to potentiate the lesions, suggesting that the association of the strain with the factors should first be evaluated for each experimental protocol.

This study investigated the immune response of broiler chickens with oral treatment of a Lactobacillus spp. pool (PL) associated with microencapsulat

Nóbrega JC, et al. J Vet Sci. 2024 Mar;25:e27. https://doi.org/10.4142/jvs.23268

Salmonella Minnesota (SM) is considered an emerging serovar, adapted to the poultry production chain, frequently associated with antimicrobial resistance, biofilm formation, and environmental persistence. This study aimed to characterize SM isolates from a poultry slaughterhouse regarding phenotypic and genotypic profiles of antimicrobial resistance, biofilm-forming capacity, thermal tolerance, genotypic virulence profile, and clonal relatedness. Strains obtained from carcasses (n = 26), cecal contents (n = 25), and chiller water (n = 11) from the slaughterhouse were evaluated. A high frequency of resistance to β-lactams, multidrug-resistant phenotypes, and extended-spectrum β-lactamase-producing isolates were observed. All isolates harbored genes associated with virulence and biofilm formation (invA, csgD, and adrA). Biofilm formation was influenced by temperature, with greater intensity at refrigeration temperatures, especially on stainless steel surfaces. In thermal tolerance assays, a negative correlation between temperature and bacterial viability was observed. Genetically related lineages circulating among cecum, carcass, and slaughterhouse chiller water over time were observed. These findings indicate that the persistence of SM in poultry slaughterhouses is sustained by the interaction between antimicrobial resistance, adaptive capacity associated with biofilm formation, and the circulation of genetically related lineages, representing a relevant challenge for food safety and public health.

Neste estudo, as principais variáveis do teste de antagonismo Spot-on-the-Lawn, como concentrações de Salmonella Heidelberg e Lactobacillus salivarius ATCC 11742 e volumes de meio foram investigadas, sendo ao final proposto um modelo de padronização, visando à diminuição de variações individuais e à replicabilidade do teste. Três concentrações de cada bactéria foram preparadas (concentrada, intermediária e diluída), além de três volumes de caldo Brain Heart Infusion (10, 15 e 20mL). O teste de antagonismo foi realizado, sob todas as variações, entre concentrações bacterianas e volumes de meio, resultando em 27 unidades experimentais diferentes e nove halos de inibição por unidade. As comparações permitem concluir que o uso de valores extremos para as concentrações de ambas as bactérias e os volumes de meio leva à super ou subestimação dos halos de inibição. Assim, o ideal é a utilização de concentrações bacterianas e de volumes de meio similares e intermediárias.