“…Most of the peripheral blood lymphocytes of Muscovy ducks are T cells, which are important in mediating cellular immunity ( Wu et al, 2019 ). After stimulation with nonspecific antigen ConA in vitro, they can transform into lymphoblasts for lymphocyte proliferation ( Alekseeva et al, 2021 ). Therefore, the degree of T lymphocyte transformation and proliferation reflects the level of cellular immunity in the body ( Hafez et al, 2020 ).…”