Analisis gen peplomer si penentu variasi serotipe virus infectious bronchitis isolat lapangan pada ayam

UNTARI, Tri, Promotor drh. Darjono, M.Sc., Ph.D

2008 | Disertasi |

Penyakit Infectious bronchitis (IB) merupakan salah satu masalah penting dalam perunggasan karena dapat menyebabkan penurunan produksi dan kwalitas telur. Perangkat diagnostik diperlukan untuk kepentingan diagnosa secara akurat, karena VIB mempunyai banyak serotipe dan varian. Isolasi, uji serologi dan analisis molekular digunakan untuk membandingkan standart virus vaksin Mass H120, varian 4/91 dan beberapa isolat virus. Penelitian ini digunakan tiga isolat yaitu U-02, C-15 dan D-07 yang diidentifikasi menggunakan HA, HH, reverse transcriptase polymerase chain reaction (RT-PCR) dan sekuensing gen S1. Hasil penelitian menunjukkan homologi sekuen nukleotida isolat U-02, dan D-07 tinggi (80%), tetapi apabila dibandingkan dengan vaksin homologinya sangat rendah yaitu dengan Mass H120 (44,7% dan 42%) dan dengan vaksin 4/91 (45,9% dan 44%). Sekuen U-02 dan D-07 dibandingkan dengan isolat Jawa Barat I-14, I-37, I-269 juga mempunyai homologi yang rendah (< 50%). Kesimpulan penelitian ini adalah secara serologi (HH) isolat lokal U-02, C-15 dan D-07 mempunyai serotipe yang sama. Secara genetik (gen S1) U-02 dan D-07 sama, tetapi berbeda dengan virus vaksin (Mass H120 dan varian 4/91), serta isolat Jawa Barat.

Infectious bronchitis is one of the major problem in poultry industries due to poor production and loss egg quality. A reliable iagnostic tool is needed to make an accurate diagnosis, since IB has many serotype and variant. Isolation, serology and molecular analysis are used to compare standard vaccine virus Mass H120, vaccine variant 4/91 and several field virus. These three isolates U–02, C-15 and D – 07 are identifical using HA, HI, RT-PCR and sequencing of S1 gene. Result of this experiment demonstrate this homology of nucleotide sequence S1 isolate U-02 and D-07 are high (80%) but very low compare to virus Mass H120 (44,7% and 42% and also low compare to variant 4/91 (45,9% and 44%). Sequence of U-02 isolate also prove to have low homology with West Java isolate I-14, I-37, I-269 (<50%). In conclusion, the serologically (HI) local isolate U- 02, C-15 and D-07 are in the same serotype, but genetically (S1 gene) U-02 and D-07 are similar although differ from that of vaccine virus (Mass H120 and variant 4/91) and West Java isolate.

Kata Kunci : Gen S1,Hemaglutinasi,RT-PCR,virus infectious bronchitis, S1 gene, hemagglutination, RT-PCR, infectious bronchitis virus.