Keberhasilan Hiperimunisasi pada Sapi Bunting: Kajian Terhadap Ketepatan Waktu Vaksinasi (THE SUCCESS OF HYPERIMMUNIZATION IN PREGNANT COWS: A STUDY OF VACCINATIONS REGIMEN) Safitria Wulandari 1 , Anita Esfandiari 2* , Sri Murtini 3 , Retno Wulansari 2 1 Program Studi Ilmu Biomedis Hewan, Sekolah Pascasarjana; 2 Divisi Penyakit Dalam Departemen Klinik Reproduksi dan Patologi; 3 Departemen Ilmu Penyakit Hewan dan Kesehatan Masyarakat Veteriner; Fakultas Kedokteran Hewan, Institut Pertanian Bogor Jl. Agatis Kampus IPB Dramaga Bogor, Jawa Barat Indonesia 16680, *Email: esfandiari1962@gmail.com ABSTRACT This study aims to determine the appropriate timing of vaccination in pregnant cow with an emphasis on effect of gestational age when the vaccine is first administrated on the success of hyperimmunization. A total of 12 Friesian Holstein pregnant cows were divided into control and vaccine groups, with each group consisting of six months of gestation (n=3) and seven months (n=3). Cows were injected with a commercial H5N1 Avian influenza (AI) vaccine (killed vaccine) sub-cutaneous, in 5 doses/head (10 6 EID50/dose). Vaccinations are carried out twice with two weeks intervals between vaccinations. Prior to vaccination, cows were given immunomodulator 0.1 mg/kg bw orally for three consecutive days then priming was done by injecting inactive AI H5N1 antigen without adjuvant (intravenously) three consecutive days (10x2 8 HAU/head). Blood samples were collected through the coccygeal vein before the first vaccination, two weeks post vaccination I and two weeks post vaccination II to be analyzed for the parameters of leukocytes (total leukocytes and lymphocytes), levels of total protein, globulin and albumin/globulin ratio (A/G) and IgG anti AI H5N1 titers in blood and colostrum. The results showed that there were no significant differences in the total number of leukocytes and lymphocytes, levels of total protein and globulin, A/G ratio, and antibody anti AI H5N1 titers in blood and colostrum, both between groups and between observation times (p>0.05). However, the cows in the six months gestation age vaccine group showed leukocyte parameters, total protein and globulin levels as well as antibodies anti AI H5N1 titers in blood and colostrum tended to be higher than in the seven months gestation age group. The regimen of vaccination of late trimester pregnant cows did not affect by age gestation to overcome of hyperimmunization success. Keywords: Avian influenza H5N1; hyperimmunization; bovine colostrums; immunoglobulin G ABSTRAK Penelitian ini bertujuan untuk melihat pengaruh umur kebuntingan induk sapi saat vaksin pertama kali diberikan terhadap keberhasilan hiperimunisasi. Sebanyak 12 ekor induk sapi bunting jenis sapi Friesian Holstein, dibagi menjadi kelompok kontrol dan vaksin, dengan masing-masing kelompok terdiri dari umur kebuntingan enam bulan (n=3) dan tujuh bulan (n=3). Induk sapi diinjeksi vaksin Avian influenza (AI) H5N1 komersial (killed vaccine) sub-kutan, sebanyak 5 dosis/ekor (10 6 EID50/dosis). Vaksinasi dilakukan dua kali dengan interval antar vaksinasi selama dua minggu. Sebelum vaksinasi, induk sapi diberi imunomodulator 0,1 mg/kg bb per oral selama tiga hari berturut-turut kemudian dilakukan priming dengan menyuntikkan antigen AI H5N1 inaktif tanpa adjuvant (intravena) tiga hari berturut-turut (10x2 8 HAU/ekor). Sampel darah dikoleksi melalui vena coccygea sebelum vaksinasi pertama, dua minggu pascavaksinasi I dan dua minggu pascavaksinasi II untuk dianalisis terhadap parameter leukosit (jumlah total leukosit dan limfosit), kadar total protein, globulin dan rasio albumin/ globulin (A/G), serta titer IgG anti AI H5N1 dalam darah dan kolostrum. Hasil pengamatan menunjukkan tidak terdapat perbedaan yang signifikan pada jumlah total leukosit dan limfosit, kadar total protein dan globulin, rasio A/G, serta titer IgG anti AI H5N1 dalam darah dan kolostrum, baik antar kelompok 88 Jurnal Veteriner pISSN: 1411-8327; eISSN: 2477-5665 Terakreditasi Nasional, Dirjen Penguatan Riset dan Pengembangan, Maret 2022 Vol. 23 No. 1 : 88 - 98 DOI: 10.19087/jveteriner.2022.23.1.88 online pada http://ojs.unud.ac.id/index.php/jvet Kemenristek Dikti RI S.K. No. 36a/E/KPT/2016