Jones Simon R M, Price Derek
Fisheries and Oceans Canada, Pacific Biological Station, Nanaimo, BC V9T 6N7, Canada.
Fisheries and Oceans Canada, Aquaculture Management, Courtenay, BC V9N 2M2, Canada.
Microorganisms. 2022 May 17;10(5):1039. doi: 10.3390/microorganisms10051039.
Gill disorders and diseases are emergent health concerns affecting marine-farmed salmon, for which the causal factors are poorly understood in British Columbia (BC), Canada. This study sought to describe and compare spatial and temporal patterns of infection with , the causal agent of amoebic gill disease, and visually assessed gill health scores in farmed Atlantic salmon. Gill tissue obtained during the Fisheries and Oceans Canada's Fish Health Audit and Intelligence Program (DFO-FHAIP) between 2016 and 2020 were screened for by qPCR. Semi-quantitative visual gill health assessments were conducted during the audits, and farms were assigned clinical AGD status based on microscopic visualization of together with histopathological lesions. Seawater temperature and salinity data were collected from all active farms in the region during the study period. Trends in gill scores and associations with infections were described and tested using an ordinal logistic mixed model. The amoeba was detected in 21% of 345 audited farms and in 12% of 1925 fish samples. Most (56%, n = 1898) samples had no visible gill damage (score = 0), and 23% had scores ≥ 2 (high). Distinct patterns of spatial and temporal variability in the rates of high gill scores and infections are demonstrated. The model supported the statistically significant relationship observed between seawater temperature and the proportion of samples with elevated gill scores. The model also revealed a direct relationship between salinity and gill score but only in the presence of . While the data suggest that histopathological lesions contributed to the gill scores, temperature and, to a lesser extent, salinity were significant risk factors of increased gill score. The results are discussed in the context of recently frequent thermal anomalies in the northeastern Pacific Ocean.
鳃部疾病是影响海水养殖三文鱼的突发健康问题，在加拿大不列颠哥伦比亚省（BC），其致病因素尚不清楚。本研究旨在描述和比较养殖大西洋三文鱼感染阿米巴鳃病病原体——[病原体名称未给出]的空间和时间模式，并直观评估鳃部健康评分。在2016年至2020年加拿大渔业和海洋部的鱼类健康审计与情报计划（DFO - FHAIP）期间获取的鳃组织，通过定量聚合酶链反应（qPCR）检测[病原体名称未给出]。在审计期间进行了半定量的鳃部健康直观评估，并根据[病原体名称未给出]的显微镜观察结果以及组织病理学损伤情况，为养殖场确定临床阿米巴鳃病状态。在研究期间，从该地区所有活跃养殖场收集了海水温度和盐度数据。使用有序逻辑混合模型描述并测试了鳃部评分趋势以及与[病原体名称未给出]感染的关联。在345个接受审计的养殖场中，21%检测到了这种变形虫，在1925个鱼类样本中，12%检测到了。大多数（56%，n = 1898）样本没有可见的鳃部损伤（评分 = 0），23%的样本评分≥2（高）。研究表明，高鳃部评分率和[病原体名称未给出]感染率存在明显的空间和时间变化模式。该模型支持了海水温度与鳃部评分升高的样本比例之间观察到的统计学显著关系。该模型还揭示了盐度与鳃部评分之间的直接关系，但仅在存在[病原体名称未给出]的情况下。虽然数据表明组织病理学损伤对鳃部评分有影响，但温度以及在较小程度上盐度是鳃部评分升高的重要风险因素。在东北太平洋近期频繁出现热异常的背景下对结果进行了讨论。
