Lactococcosis, mainly sustained by the warm-water bacterium Lactococcus garvieae, is a disease associated with evident mortalities and economic lossed. Main disease signs are commonly bilateral exophthalmia, hyperpigmentation in the body, haemorrhages around the eye area, opercula, and mouth region, swollen abdomen, and anal prolapse. An effective monitoring system of fish diseases relies on rapid techniques for the timely management of infection outbreaks. We evaluated the potential of the SCiO sensor, a portable near infrared spectroscope, to assess in field the health status of rainbow trout. The study sample was composed of 20 symptomatic and 20 asymptomatic rainbow trout obtained from an aquaculture farm and submitted to molecular detection of L. garvieae and SCiO examination. In order to detect presence or absence of septicaemia condition, blood smears were prepared from peripheral blood. Part of the symptomatic individuals (9/20) showed septicaemia, whereas no bacteria were found in the asymptomatic individuals. PCR assay of bacterial DNA was positive in spleen and kidney of 19/20 symptomatic and in 1/20 asymptomatic individuals. Bacteriological analysis revealed L. garvieae in 18/20 symptomatic samples and in 2/20 asymptomatic samples. The SCiO sensor was found to be able to discriminate between healthy and sick fish [sensibility 0.95 (0.75–1.00 I.C. 95%), specificity 0.80 (0.56–0.94 I.C. 95%)]. By virtue of rapid acquisition, low cost and use on site, the SCiO was considered as a useful diagnostic tool for monitoring L. garvieae infection in rainbow trout.

乳球菌病主要由温水细菌加维乳球菌引起，是一种导致明显死亡和经济损失的疾病。主要疾病症状通常为双侧眼球突出、身体色素沉着过度、眼部周围、鳃盖和口腔区域出血、腹部肿胀和肛门脱垂。有效的鱼病监测系统依赖于及时管理感染爆发的快速技术。我们评估了 SCiO 传感器（一种便携式近红外光谱仪）在现场评估虹鳟鱼健康状况的潜力。研究样本由从水产养殖场获得的 20 条有症状虹鳟鱼和 20 条无症状虹鳟鱼组成，并进行了L. garvieae分子检测和 SCiO 检查。为了检测是否存在败血症状况，从外周血制备血涂片。部分有症状个体（9/20）出现败血症，而无症状个体中未发现细菌。19/20 有症状个体和 1/20 无症状个体的脾脏和肾脏细菌 DNA PCR 检测呈阳性。细菌学分析显示，18/20 有症状样本和 2/20 无症状样本中存在加氏乳杆菌。SCiO 传感器被发现能够区分健康和患病的鱼 [灵敏度 0.95 (0.75–1.00 IC 95%)，特异性 0.80 (0.56–0.94 IC 95%)]。SCiO 凭借快速获取、低成本和现场使用等优点，被认为是监测虹鳟鱼中加维埃利希氏菌感染的有用诊断工具。