Variation and Association of Avian β-Defensin 2 Gene with the Concentration of Immunoglobulin Y and the Titer of Newcastle-Disease Antibody in IPB-D1 Chicken

D. Lestari (Department of Animal Production and Technology, Faculty of Animal Science, IPB University)
Masruroh (Department of Animal Production and Technology, Faculty of Animal Science, IPB University)
I. Khaerunnisa (Research Center for Biotechnology, Research Organization for Life Sciences, National Research and Innovation Agency (BRIN))
S. Murtini (Department of Animal Disease and Veterinary Public Health, Faculty of Veterinary Medicine, IPB University)
N. Ulupi (Department of Animal Production and Technology, Faculty of Animal Science, IPB University)
A. Gunawan (Department of Animal Production and Technology, Faculty of Animal Science, IPB University)
C. Sumantri (Department of Animal Production and Technology, Faculty of Animal Science, IPB University)

Tropical Animal Science Journal
Vol. 45 No. 2 (2022): Tropical Animal Science Journal

Defensins play roles in innate immunity by exhibiting antimicrobial activity against microbes such as gram-negative and -positive bacteria, viruses, and fungi. This study aimed to identify variants of the Avian β-Defensin 2 (AvBD2) and determine their associations with the concentration of immunoglobulin Y and the titer of Newcastle disease (ND) antibody in IPB-1 chicken. The chicken population used in this study was 21-week-old IPB-D1 chickens (n=90). Variations in AvBD2 were analyzed by direct DNA sequencing. IgY concentration was measured by indirect ELISA, and the titer of ND antibody was measured by the hemagglutination-inhibition test. The AvBD2 association was analyzed by the general linear model procedure and Duncan’s multiple range test. The results revealed 10 SNPs located in intron 1 (3 SNPs), exon 2 (3 SNPs), and intron 2 (4 SNPs). Six of these SNPs were associated with IgY concentration. The CC genotype of g.5002 C>T was associated with IgY concentration and produced the highest mean IgY concentration. This g.5002 C>T mutation results in alanine-to-valine substitutions. The CC genotype of g.5002 C>T could be considered as a criterion for selecting chickens with high IgY concentrations.