Abstract
BACKGROUND AND AIM: IPB-D2 chickens are selected from IPB-D1 due to their disease-resistance characteristics. One-way to evaluate the strength of a chicken's immune system is by examining the number of circulating T lymphocytes. This assessment can be conducted using a modern analytic method called flow cytometry which relies on monoclonal antibodies to detect the relative proportions of each cell and measure the quality and quantity of biological and physical features of cells, including specific membrane or intracellular glycoprotein markers. Therefore, this study aimed to evaluate the population of lymphocytes, cluster of differentiation (CD)4(+) and CD8(+) in IPB-D2 chickens. MATERIALS AND METHODS: Flow cytometry was used to evaluate the population of lymphocytes, CD4(+), and CD8(+) in IPB-D2 chickens. The data obtained in this study were analyzed by Minitab, and the mean values were compared using a t-test. RESULTS: The lymphocytes, CD4(+), and CD8(+) populations of IPB-D2 chicken with high Newcastle disease (ND) antibody titers were 65.04%, 10.53%, and 5.47%. Meanwhile, this breed, with low ND antibody titers had lymphocytes CD4(+) and CD8(+) population of 57.19%, 8.40%, and 4.11 %. The comparison of CD4(+) and CD8(+) populations in chickens with high and low ND antibody titers was 1.92 and 2.04, respectively. CONCLUSION: IPB-D2 chickens with high ND antibody titers exhibited increased lymphocyte, CD4(+), and CD8(+) cell populations in comparison to those with low ND antibody titers. However, the high ND antibody titer group had a lower CD4(+)/CD8(+) ratio.