Auburn University Shellfish Laboratory, 150 Agassiz Street, Dauphin Island, Alabama, 36528, USA.
J Food Prot. 2013 Jan;76(1):119-23. doi: 10.4315/0362-028X.JFP-12-315.
Increasingly strict standards for harvest of oysters for the raw, half-shell market (designated as "white tag") should increase the proportion of oysters not meeting these standards (designated as "green tag"). Transplanting of green tag oysters into highsalinity waters (>20 practical salinity units) was explored as a means of returning Vibrio vulnificus and Vibrio parahaemolyticus levels to levels present on initial harvest. In summer 2011, oysters originally harvested in Louisiana were transplanted on two separate occasions (n = 2) to two sites in Mississippi Sound, AL: Sandy Bay and Dauphin Island. Oysters were tested for V. vulnificus and V. parahaemolyticus densities (by using the U.S. Food and Drug Administration enrichment method) after 2, 7, and 14 days deployed, with baseline samples taken (i) at the time of original harvest and iced, (ii) from oysters refrigerated within 1 h of harvest at <45°F ([7.2°C] white tag) and, (iii) from oysters not refrigerated during the harvest trip (green tag) but refrigerated after an 8-h trip. White and green tag oysters were sampled ∼24 h on arrival in Bon Secour, AL, put on ice, and shipped for analysis. Among baseline samples, there were no significant differences in V. vulnificus and V. parahaemolyticus densities, although the densities in the green tag oysters tended to be highest. After transplanting, V. vulnificus densities were significantly highest on day 2, with no significant differences among any of the other days within a site. On day 2, Sandy Bay had significantly greater densities of V. vulnificus than the Dauphin Island site, but no other days differed from time zero. For Vibrio parahaemolyticus, densities were greatest on day 2 and lowest at time zero, but this did not differ significantly from abundance on day 14. Average survival was 83.4% (± 3.13 SD), with no differences between sites. These preliminary results indicate that high-salinity transplanting could be an effective method of converting green tag oysters to oysters suitable for "reharvest" as white tag oysters.
为了满足生食、半壳牡蛎的日益严格标准（指定为“白标签”），牡蛎的不合格率（指定为“绿标签”）应该会增加。因此，人们探索了将绿标签牡蛎移植到高盐度水域（>20 个实用盐度单位）的方法，以期将创伤弧菌和副溶血性弧菌的水平恢复到初始收获时的水平。2011 年夏天，路易斯安那州最初收获的牡蛎被分两次（n = 2）移植到阿拉巴马州墨西哥湾的两个地点：桑迪湾和多芬岛。牡蛎在部署后第 2、7 和 14 天用美国食品和药物管理局的富集方法检测创伤弧菌和副溶血性弧菌的密度，并在以下时间采集基线样本：(i) 初始收获时以及冰鲜时，(ii) 在收获后 1 小时内冷藏（<45°F [7.2°C]，即白标签）时，以及 (iii) 收获过程中未冷藏但收获后 8 小时内冷藏（绿标签）的牡蛎。白标签和绿标签牡蛎抵达博恩赛康后，约 24 小时采样，放入冰中，然后运到分析地。在基线样本中，创伤弧菌和副溶血性弧菌的密度没有显著差异，尽管绿标签牡蛎的密度往往最高。移植后，创伤弧菌的密度在第 2 天最高，在一个地点内的任何其他日期均无显著差异。第 2 天，桑迪湾的创伤弧菌密度明显高于多芬岛，而其他时间则与零时间点无差异。对于副溶血性弧菌，第 2 天的密度最高，而零时间点的密度最低，但与第 14 天的丰度无显著差异。平均存活率为 83.4%（± 3.13 SD），两个地点之间没有差异。这些初步结果表明，高盐度移植可能是将绿标签牡蛎转化为适合作为“再收获”的白标签牡蛎的有效方法。
