This study investigated the effects of probiotic supplementation on performance, egg quality, antioxidant capacity, gut morphology, fecal microbiota, and bone morphology in Lohmann Brown laying hens aged 44 weeks over a 16-week period. Ninety-six hens were randomly divided into control and probiotic groups (n = 48 each). The probiotic group received probiotic supplement containing Lactobacillus acidophilus KUEN 1607 and Pediococcus acidilactici KUEN 1608 via drinking water at 0.5%. Probiotic supplementation significantly improved feed conversion ratio (FCR), eggshell strength and thickness, and albumen quality (p < 0.001) and reduced the incidence of cracked and shell-less eggs (p < 0.05). Yolk and serum cholesterol levels decreased (p < 0.001), and antioxidant parameters improved, along with elevated serum IgG (p < 0.001). Histological analysis showed an increased ratio of villus height to crypt depth (p < 0.001) in the jejunum, indicating enhanced intestinal health. Fecal samples revealed increased Lactobacillus spp. and reduced coliform counts (p < 0.001), suggesting improved gut microbiota balance. While bone volume and surface area showed no significant difference, 3D geometric morphometric analysis identified subtle shape changes in long bones, especially the femur and tibiotarsus. These findings demonstrate that the selected probiotic combination supports nutrient utilization, egg quality, gut integrity, immune status, and skeletal health, offering a sustainable strategy to enhance productivity and welfare in laying hens.

The aim of this study is to determine the effect of abrupt and gradual light/dark switching on growth performance, behavior, villus development, meat characteristics, and immunity of broilers. A total of 270 daily male broiler chicks were used in the experiment. The study comprised three groups based on whether the transitions between light and dark periods were abrupt or gradual. No significant differences were observed among the examined groups in terms of body weight, weight gain, mortality rate, feeding, pecking, relaxing, and feather preening behaviors, carcass, and breast meat quality characteristics. Total body weight gain, total feed consumption, total feed utilization ratio, and mortality rates of broilers during the 6‐week fattening period did not differ compared to the abrupt transition. Broilers in the group with gradual transition exhibited less movement, more sitting, and sleeping behaviors. It was determined that the IgG was higher in the gradual transition group. The transitions between light and dark periods influenced the characteristics of thigh meat. Villus height and crypt depth were higher in the group where a 1‐h gradual transition was applied. As a conclusion, gradual transition is more appropriate in broiler rearing.

Tobacco usage is linked to multiple cancer types and accounts for a quarter of all cancer-related deaths. Tobacco smoke contains various carcinogenic compounds, including polycyclic aromatic hydrocarbons (PAH), though the mutagenic potential of many tobacco-related chemicals remains largely unexplored. In particular, the highly carcinogenic tobacco-specific nitrosamines NNN and NNK form pre-mutagenic pyridyloxobutyl (POB) DNA adducts. In the study presented here, we identified genome-scale POB-induced mutational signatures in cell lines and rat tumors, while also investigating their role in human cancer. These signatures are characterized by T>N and C>T mutations forming from specific POB adducts damaging dT and dC residues. Analysis of 2,780 cancer genomes uncovered POB signatures in ∼180 tumors; from cancer types distinct from the ones linked to smoking-related signatures SBS4 and SBS92. This suggests that, unlike PAH compounds, the POB pathway may contribute uniquely to the mutational landscapes of certain hematological malignancies and cancers of the kidney, breast, prostate and pancreas.