Effects of Combined Red Ginger–Temulawak Herbal and Probiotic Supplementation During the Pre-Laying Period on Newcastle Disease Antibody Titers in ISA Brown Laying Hens

Newcastle Disease (ND) continues to pose a serious challenge to the poultry industry despite routine vaccination programs. This study aimed to evaluate the effect of combined herbal and probiotic supplementation on ND antibody titers in ISA Brown laying hens during the pre-laying period. Forty 16-week-old hens were randomly divided into two groups: a control group receiving a basal diet and a treatment group receiving a basal diet supplemented with red ginger (Zingiber officinale var. rubrum), temulawak (Curcuma xanthorrhiza), Bacillus subtilis, and Lactobacillus acidophilus for three months. Antibody titers were measured using the hemagglutination inhibition (HI) test at 16 weeks (pre-vaccination), 19 weeks (two weeks post-vaccination), and 23 weeks (six weeks post-vaccination). Although numerical differences in mean titers and geometric mean titers (GMT) were observed between groups, statistical analysis using the Mann–Whitney test and independent t-test showed no significant differences (P > 0.05). These results suggest that the combined supplementation did not significantly enhance ND antibody responses beyond vaccination alone under the conditions of this study.