GRAZIELA ANGELICHA MANDALA Pengarang MAXS URIAS EBENHAISER SANAM Dosen Pembimbing 2 Elisabeth Levina Sari Setianingrum Ketua Penguji Frans Umbu Datta Penguji 2 Maxs Urias Ebenhaiser Sanam Penguji 1

Newcastle Disease (ND) is one of the poultry farming industry's most devastating diseases. Vaccination can minimize symptoms and provide protection against ND for chickens. High temperatures in arid environments can inhibit the development of immune cells. The IPB D1 chicken is a hybrid between a local chicken and a purebred chicken with increased disease resistance. This study compared the antibody titers of IPB D1 chickens vaccinated through drinking water, a group of chickens vaccinated intramuscularly, and a control group against Newcastle Disease vaccine. Using the hemagglutination inhibition (HI) assay, pre-and post-vaccination immune responses were determined. The group of chickens vaccinated via drinking water had an average pre-vaccination antibody titer of 1.8 ± 0.29 log 2, which began to rise at 3.3± 0.65 log 2, 5.31± 0.73 log 2, and 3.2± 0.38 log 2 at two, four, and eight weeks, respectively. In the pre-vaccinated intramuscular group, the mean antibody titer was 1.6± 0.16 log 2, 5.4± 0.98 log 2 at 2 weeks post-vaccination, 4.89± 0.9 log 2 at 4 weeks post-vaccination, and 3.56± 0.66 at 8 weeks post-vaccination. It was either that ND vaccination via drinking water or intramuscular methods could boost antibodies to a mean titer greater than 4 HI log 2 in a minimum of four weeks. The conclusion that the antibody titer of IPB D1 chickens vaccinated intramuscularly grew more rapidly than those vaccinated via drinking water.