Lysozyme， a naturally occurring multifunctional protein， exerts antibacterial effects through peptidoglycan（PG） hydrolysis and a cation ? dependent，non ? enzymatic mechanism. It also possesses antiviral properties by binding to cellular receptors or viral particles，thereby inhibiting viral entry，sequestering viral nucleic acids，and inhibiting virus?induced cell fusion. These mechanisms contribute to its broad application value across diverse fields such as food preservation，adjunctive medical therapy，and livestock production. Antibiotics are widely used in livestock production to treat bacterial infections，boost animal immunity，and reduce the risk of disease transmission. However，the overuse or misuse of antibiotics can lead to bacterial resistance，drug residues，and potential health risks. Therefore，lysozyme，as a promising alternative，holds great potential in promoting the transition to antibiotic?free，sustainable livestock production. This review provides an overview of the antibacterial and antiviral mechanisms of lysozyme，along with the latest research on its applications in livestock production. It also addresses the technical challenges and limitations encountered in its practical use. The aim is to offer a theoretical basis for the scientific application of lysozyme in the healthy farming of livestock and poultry and to facilitate its industrial development as an antibiotic alternative.

This study aimed to investigate the quality differences of eggs from caged partridges at different ages （300 d，500 d，and 800 d）to provide a scientific basis for partridge egg selection and breeding management. By measuring parameters such as egg weight，eggshell weight，egg shape index，eggshell strength，eggshell thickness， Haugh unit， yolk weight， yolk ratio， and albumen height， and performing correlation analysis， the study systematically assessed the changes in egg quality with age. The results showed that：（1）Egg weight and eggshell thickness significantly increased with age（ P<0.05），whereas eggshell weight，eggshell strength，and yolk ratio first increased and then decreased，peaking at 500 d；（2）The Haugh Unit of eggs at 300 d was the highest（83.68 HU）；（3） The egg shape index was significantly negatively correlated with eggshell strength（ P<0.05），and the eggshell thickness of eggs at 800 d（0.31 mm）was significantly greater than that of other ages. The study concluded that the eggs from partridges at 500 d had the best comprehensive quality，and it is recommended that in breeding production，high⁃ quality eggs be selected based on egg quality indicators.