Southard Gregory M, Fries Loraine T, Terre David R
Texas Parks and Wildlife Department, A. E. Wood Laboratory, San Marcos, Texas 78666, USA.
J Aquat Anim Health. 2009 Mar;21(1):36-42. doi: 10.1577/H08-027.1.
In response to fish kills at prominent fishing sites for largemouth bass Micropterus salmoides, such as Lake Fork and Sam Rayburn Reservoir, the Texas Parks and Wildlife Department began a systematic evaluation of state waters for the presence of largemouth bass virus (LMBV). The survey comprised 49 water bodies and 13 river basins, and a total of 2,876 adult bass were collected by electrofishing and angling during the summer and fall of 2000. The virus was initially detected by means of cell culture and its presence subsequently confirmed by polymerase chain reaction. Fourteen reservoirs in eight river basins in eastern and central Texas tested positive for LMBV. Lake Fork was also tested to determine the prevalence of infection following a 1999 LMBV fish kill. The overall prevalence was low in all of the water bodies tested (1.50 +/- 2.82% [mean +/- SD]) as well as those determined to contain LMBV (5.00 +/- 3.02%). Largemouth bass testing positive for LMBV had a significantly higher prevalence of swim bladder anomalies, but this condition was not a good indicator of LMBV infection. No significant relationships were found between LMBV-positive fish and other factors investigated, including the presence or absence of grossly visible injury, hook marks, external parasites, known water quality problems, gender, allozyme-phenotype, method of capture, length, weight, body condition (relative weight), or age. This survey provided a means of gathering scientific information about LMBV, including its distribution in Texas. From the information gained by this survey, prior fish kills, and previous sampling efforts, a total of 19 water bodies within 9 of the 13 major river basins in the state were found to contain the virus. These results were used to guide a statewide fish stocking strategy aimed at preventing the spread of LMBV in Texas and to contribute to a nationwide effort to understand this virus and its effects on largemouth bass fisheries.
针对大口黑鲈（Micropterus salmoides）主要捕鱼地点如福克湖和山姆·雷伯恩水库出现的鱼类死亡事件，得克萨斯州公园与野生动物部开始对该州水域进行系统评估，以检测是否存在大口黑鲈病毒（LMBV）。此次调查涵盖了49个水体和13个流域，在2000年夏秋季节，通过电捕和垂钓共采集了2876尾成年鲈鱼。该病毒最初通过细胞培养检测到，随后通过聚合酶链反应确认其存在。得克萨斯州东部和中部八个流域的14个水库检测出LMBV呈阳性。福克湖在1999年发生LMBV导致的鱼类死亡事件后也进行了检测，以确定感染率。在所有检测的水体中，总体感染率较低（1.50±2.82%[平均值±标准差]），在确定含有LMBV的水体中也是如此（5.00±3.02%）。检测出LMBV呈阳性的大口黑鲈鳔异常的发生率显著更高，但这种情况并不是LMBV感染的良好指标。在LMBV呈阳性的鱼与其他调查因素之间未发现显著关系，这些因素包括是否有明显可见的损伤、鱼钩痕迹、体外寄生虫、已知的水质问题、性别、等位酶表型、捕获方法、体长、体重、身体状况（相对体重）或年龄。这项调查提供了一种收集有关LMBV科学信息的方法，包括其在得克萨斯州的分布情况。根据此次调查、先前的鱼类死亡事件以及之前的采样工作所获得的信息，该州13个主要流域中的9个流域内共有19个水体被发现含有这种病毒。这些结果被用于指导全州范围内的鱼类放养策略，旨在防止LMBV在得克萨斯州传播，并为全国范围内了解这种病毒及其对大口黑鲈渔业的影响做出贡献。
