Klesius Phillip H, Evans Joyce J, Shoemaker Craig A, Pasnik David J
U.S. Department of Agriculture, Agricultural Research Service, Aquatic Animal Health Research Laboratory, Auburn, AL 36831-0952, USA.
Fish Shellfish Immunol. 2006 Jan;20(1):20-8. doi: 10.1016/j.fsi.2005.03.003.
A vaccination and challenge cohabitation model was established and evaluated using Nile tilapia (Oreochromis niloticus), the fluorescent chromophore calcein, and a Streptococcus iniae vaccine. Tilapia were non-invasively calcein marked, sham-vaccinated (CMSV) and cohabited with non-marked sham-vaccinated (NMSV) or non-marked S. iniae vaccinates (NMV) as a single unit. After 30 d, the cohabitants were challenged with a virulent isolate of S. iniae by intraperitoneal (ip) injection and the cumulative mortality was measured over a period of 15 d. Calcein marking did not have a significant effect on S. iniae susceptibility as mortality of CMSV and NMSV was not significantly different (P=0.6756). Nor did calcein marking have an effect on the vaccination and challenge cohabitation model. The results showed that the cumulative mortality of CMSV (N=160) was significantly greater (P<0.0003) than those of NMV (N=160). The results of the calcein marking trials indicate that the most suitable calcein concentration and exposure time to produce detectable fluorescent marking of tilapia was 500 mg L(-1) for 4 h. Furthermore, the calcein marks were readily visible in the calcified skeletal structures of head and fins using a portable handheld UV lamp set at 365 nm wavelength. Calcein appears to be a valuable tool for non-invasive, non-lethal, non-stressful, mass marking of fish to differentiate between sham- and pathogen-vaccinated fish in this cohabitation model. The vaccination and challenge cohabitation model also offers the statistical advantage of using individual fish as the experimental unit maintained in the same aquarium.
利用尼罗罗非鱼（尼罗罗非鱼）、荧光发色团钙黄绿素和海豚链球菌疫苗建立并评估了一种疫苗接种与攻毒同居模型。罗非鱼用钙黄绿素进行非侵入性标记，进行假疫苗接种（CMSV），并作为一个单元与未标记的假疫苗接种鱼（NMSV）或未标记的海豚链球菌疫苗接种鱼（NMV）同居。30天后，通过腹腔注射用海豚链球菌的强毒株对同居鱼进行攻毒，并在15天内测量累积死亡率。钙黄绿素标记对海豚链球菌易感性没有显著影响，因为CMSV和NMSV的死亡率没有显著差异（P = 0.6756）。钙黄绿素标记对疫苗接种与攻毒同居模型也没有影响。结果表明，CMSV（N = 160）的累积死亡率显著高于NMV（N = 160）（P < 0.0003）。钙黄绿素标记试验结果表明，产生可检测到的罗非鱼荧光标记的最合适钙黄绿素浓度和暴露时间为500 mg L(-1) 4小时。此外，使用波长设置为365 nm的便携式手持式紫外线灯，在头部和鳍的钙化骨骼结构中很容易看到钙黄绿素标记。在这种同居模型中，钙黄绿素似乎是一种用于对鱼类进行非侵入性、非致死性、无应激的大规模标记，以区分假疫苗接种鱼和病原体疫苗接种鱼的有价值工具。疫苗接种与攻毒同居模型还具有将单个鱼作为维持在同一水族箱中的实验单元的统计优势。
