Bacillus NP5 Improves Growth Performance and Resistance Against Infectious Myonecrosis Virus in White Shrimp (Litopenaeus vannamei) (Bacillus NP5 Meningkatkan Pertumbuhan dan Ketahanan Terhadap Infeksi Virus Myonecrosis pada Udang Putih (L. vannamei)

Abstrak

Infectious Myonecrosis (IMN) merupakan salah satu penyakit yang sering menyerang udang vaname. Probiotik banyak digunakan pada budidaya udang karena terbukti mampu mengurangi serangan penyakit pada udang. Penelitian ini bertujuan untuk menguji pengaruh pemberian probiotik Bacillus NP5 melalui pakan terhadap kinerja pertumbuhan, respons imun, dan resistensi udang vaname terhadap infeksi Infectious Myonecrosis Virus (IMNV). Udang vaname Litopenaeus vannamei (2.41±0.07 g ekor-1) diberi pakan yang disuplementasi probiotik Bacillus NP5 dengan dosis yang berbeda, 102 CFU.g-1 (A), 104 CFU.g-1 (B), 106 CFU.g-1 (C), dan kontrol tanpa suplementasi probiotik (kontrol negatif, KN; kontrol positif, KP) selama 30 hari dan dengan tiga ulangan untuk masing-masing dosis, kemudian KP, perlakuan A, B, dan C diuji tantang secara intramuskular dengan IMNV (100 µl.ekor-1). Hasil penelitian ini menunjukkan bahwa udang vaname yang diberi pakan dengan suplementasi probiotik mempunyai laju pertumbuhan harian (LPH), rasio konversi pakan (RKP), dan respons imun yang lebih tinggi. Udang tersebut juga mempunyai total hemocyte count (THC) dan resistensi terhadap IMNV yang lebih tinggi dibandingkan kontrol positif. Konsentrasi probiotik 106 CFU.g-1 memberikan hasil terbaik dalam meningkatkan pertumbuhan, respon imun, dan resistensi udang vaname terhadap infeksi IMNV. Kata kunci: probiotik, Bacillus NP5, Litopenaeus vannamei, pertumbuhan, IMNV Infectious Myonecrosis (IMN) is one of the most prevalent white shrimp diseases. Probiotics are widely used in shrimp cultivation because they have been proven to reduce shrimp disease outbreak. This study aimed to observe the effect of oraly administered probiotic Bacillus NP5 on the white shrimp's growth performance, immune response, and resistance to Infectious Myonecrosis Virus (IMNV) infection. White shrimp Litopenaeus vannamei (2.41±0.07 g individual-1) were fed with a feed supplemented with different doses of the probiotic Bacillus NP5, i.e. 102 CFU.g-1 (A), 104 CFU.g-1 (B), 106 CFU.g-1 (C), and control without any probiotic (negative control, KN; positive control, KP) for 30 days and with three replications for each dose, then KP, treatment A, B, and C were challenged intramuscularly with IMNV (100 µl.shrimp-1). The results of the study showed that white shrimp fed with the supplemented probiotic had higher Daily Growth Rate (DGR), Feed Conversion Ratio (FCR), and immune response. They also had the higher Total Hemocyte Count (THC) and resistance to IMNV than the positive control. Probiotic with concentration of 106 CFU.g-1 gave the highest value on enhancing growth, immunity, and resistance of white shrimp towards IMNV infection. Key words: probiotic, Bacillus NP5, Litopenaeus vannamei, growth, IMNV