Dar Showkat Ahmad, Kole Sajal, Shin Su-Mi, Jeong Hyeon-Jong, Jung Sung-Ju
Department of Aqualife Medicine, Chonnam National University, Republic of Korea.
Department of Aqualife Medicine, Chonnam National University, Republic of Korea.
Vaccine. 2021 Nov 16;39(47):6866-6875. doi: 10.1016/j.vaccine.2021.10.026. Epub 2021 Oct 22.
The profitability of the olive flounder (Paralichthys olivaceus) aquaculture industry in Korea depends on high production and maintenance of flesh quality, as consumers prefer to eat raw flounders from aquaria and relish the raw muscles as 'sashimi'. For sustaining high production, easy-to-deliver and efficient vaccination strategies against serious pathogens, such as viral hemorrhagic septicemia virus (VHSV), is very important as it cause considerable losses to the industry. Whereas, a safe and non-invasive vaccine formulation that is free from unacceptable side-effects and does not devalue the fish is needed to maintain flesh quality. We previously developed a squalene-aluminium hydroxide (Sq + Al) adjuvanted VHSV vaccine that conferred moderate to high protection in flounder, without causing any side effects when administered through the intraperitoneal (IP) injection route. However, farmers often demand intramuscular (IM) injection vaccines as they are relatively easy to administer in small fishes. Therefore, we administered the developed vaccine via IP and IM routes and investigated the safety and persistency of the vaccine at the injection site. In addition, we conducted a comparative analysis of vaccine efficacy and serum antibody response. The clinical and histological observation of the IM and IP groups showed that our vaccine remained persistence at the injection sites for 10-17 weeks post vaccination (wpv), without causing any adverse effects to the fish. The relative percentage of survival were 100% and 71.4% for the IP group and 88.9% and 92.3% for the IM group at 3 and 17 wpv, respectively. Thus, considering the persistency period (24 wpv) and both short and long-term efficacy of our vaccine, the present study offers an option to flounder farmers in selecting either IM or IP delivery strategy according to their cultured fish size and harvesting schedule - IM vaccination for small-sized fish and IP vaccination for table-sized fish.
韩国牙鲆养殖业的盈利能力取决于高产量和肉质的维持，因为消费者更喜欢食用养殖水族箱中的生牙鲆，并将生鱼片作为美食享用。为了维持高产量，针对严重病原体（如病毒性出血性败血症病毒，VHSV）的易于实施且高效的疫苗接种策略非常重要，因为该病毒会给该行业造成相当大的损失。然而，需要一种安全且非侵入性的疫苗制剂，该制剂没有不可接受的副作用且不会降低鱼的价值，以维持肉质。我们之前开发了一种以角鲨烯 - 氢氧化铝（Sq + Al）为佐剂的VHSV疫苗，该疫苗在牙鲆中提供了中度至高保护，通过腹腔内（IP）注射途径给药时不会引起任何副作用。然而，养殖户通常要求使用肌肉内（IM）注射疫苗，因为它们相对容易在小鱼中施用。因此，我们通过IP和IM途径施用了开发的疫苗，并研究了疫苗在注射部位的安全性和持久性。此外，我们对疫苗效力和血清抗体反应进行了比较分析。IM组和IP组的临床和组织学观察表明，我们的疫苗在接种后10 - 17周（wpv）在注射部位持续存在，对鱼没有造成任何不良影响。IP组在3 wpv和17 wpv时的相对存活率分别为100%和71.4%，IM组分别为88.9%和92.3%。因此，考虑到我们疫苗的持续期（24 wpv）以及短期和长期效力，本研究为牙鲆养殖户提供了一种选择，可根据养殖鱼的大小和收获时间表选择IM或IP给药策略——小型鱼采用IM疫苗接种，食用鱼采用IP疫苗接种。
