IMUNITAS SEMU (Quasi-Immunity) PADA UDANG VANAME (Litopenaeus vannamei) MENGGUNAKAN METODE INJEKSI BAKTERI Vibrio parahaemolyticus

Abstract

Infeksi Vibrio parahaemolyticus merupakan salah satu penyebab utama penyakit pada udang vaname (Litopenaeus vannamei). Penelitian ini bertujuan untuk mengetahui pengaruh Quasi-Immunity melalui metode injeksi bakteri V. parahaemolyticus terhadap respons imun udang vaname. Parameter yang diamati meliputi proteksi imun udang melalui tingkat kelangsungan hidup (TKH), respon imun udang seperti total haemocyte count (THC), aktifitas fagositik (AF), phenoloxydase (PO), respiratory burst (RB), dan histopatologi hepatopankreas. Hasil penelitian menunjukkan bahwa perlakuan injeksi belum mampu meningkatkan resistensi udang terhadap infeksi dengan patogen yang sejenis, hal tersebut ditandai dengan tingkat kelangsungan hidup (TKH) menurun pada infeksi susulan. Infeksi bakteri V. parahaemolyticus menyebabkan kerusakan hepatopancreas dan dapat menyebabkan kematian pada infeksi susulan. Namun, respon imun udang cenderung stabil sehingga Quasi-Immunity belum memberikan pengaruh yang signifikan.

Infection by Vibrio parahaemolyticus is one of the major causes of disease in Pacific white shrimp (Litopenaeus vannamei). This study aimed to evaluate the effect of Quasi-Immunity induced through the injection of V. parahaemolyticus on the immune response of Pacific white shrimp. The observed parameters included immune protection through survival rate (SR), immune responses such as total haemocyte count (THC), phagocytic activity (PA), phenoloxidase activity (PO), respiratory burst (RB), and hepatopancreatic histopathology. The results showed that the injection treatment was unable to enhance shrimp resistance against subsequent infection by the same pathogen, as indicated by a decreased survival rate following the secondary challenge. Infection with V. parahaemolyticus caused hepatopancreatic damage and led to mortality during the subsequent infection. However, the shrimp immune responses tended to remain stable, suggesting that Quasi-Immunity did not exert a significant effect on the measured immune parameters.