Judul: The Effectiveness of Marine Bacterial Microcapsule in Controlling Vibriosis Disease Caused by The Infection of Vibrio parahaemolyticus in White Shrimp Litopenaeus vannamei
Abstrak: Vibriosis merupakan penyakit bakteri utama pada budidaya udang yang disebabkan oleh Vibrio spp. Penyakit ini mengakibatkan kematian dalam skala besar. Salah satu strategi untuk mengontrol penyakit tersebut adalah macam mikrokapsul bakteri laut selama 30 hari, yaitu Bacillus subtilis P2.24, Brevibacterium casei D6.6, dan Bacillus altitudinis D6.19. Selanjutnya udang diuji tantang dengan V. parahaemolyticus (106 CFU/ml) pada hari ke-31. Pemberian tiga mikrokapsul bakteri laut mampu mengendalikan vibriosis pada udang vaname. Mikrokapsul bakteri laut B. subtilis P2.24 menunjukkan efektivitas terbaik sebagai agen anti-vibriosis dibuktikan dengan tingginya kelangsungan hidup udang setelah 7 hari uji tantang, yaitu 40% lebih tinggi dibanding kontrol positif (Uji Duncan p<0.05). Di samping itu, ketiga mikrokapsul bakteri laut juga dapat meningkatkan respons imun (total hemocyte count, persentase sel semi-granular/granular, aktivitas phenoloxidase, respiratory burst, dan ekspreasi gen imunitas), keragaman mikrobiota, dan total viable bacterial count di usus udang. Selain itu, mikrokapsul bakteri laut juga dapat menurunkan total vibrio count, dan total V. parahaemolyticus count di usus udang, serta kerusakan pada hepatopankreas dan otot. Kesimpulannyapenggunaan mikrokapsul bakteri laut. Penelitian ini bertujuan untuk mengevaluasi efektivitas mikrokapsul bakteri laut dalam mengontrol vibriosis pada udang vaname. Udang diberi pakan yang telah diperkaya tiga, isolate B. subtilis P2.24 dapat menjadi agen biokontrol vibriosis dan alternatif pencegahan vibriosis., Vibriosis is a major bacterial disease in shrimp farming, which is caused by Vibrio spp. It has resulted in substantial shrimp mortality. One strategy to control this disease is to use microcapsules containing marine bacteria. This study was established to evaluate the effectiveness of such microcapsules in controlling vibriosis in white shrimp. The shrimps were fed a diet with microcapsules containing three different bacteria, namely, Bacillus subtilis P2.24, Brevibacterium casei D6.6, and Bacillus altitudinis D6.19, for 30 days. The shrimps were then tested by injecting V. parahaemolyticus (106 CFU/ml) on the 31st day. The administration of microcapsules containing the three marine bacteria had a positive effect on white shrimp. The microcapsules with B. subtilis P2.24 showed the best effectiveness as an anti-vibriosis agent, as indicated by the high survival rate after 7 days of challenge test, which was 40% higher than that in the positive control (Duncan’s test p < 0.05). Furthermore, the microcapsules containing the three marine bacteria promoted immune responses [i.e., total hemocyte count, percentage of semi-granular/granular cells, phenoloxidase activity, respiratory burst, and immune-related gene expression], microbiota diversity, and total viable bacterial count in shrimp intestinal tract. In addition, the microcapsules reduced the total Vibrio count and total V. parahaemolyticus count in shrimp intestinal tract, as well as the damage to hepatopancreas and muscle. In conclusion, the B. subtilis P2.24 isolate is a potential vibriosis biocontrol agent and an alternative for preventing vibriosis.
Keyword: immune responses, microbiota diversity, Litopenaeus vannamei, bacteria microcapsule, vibriosis