Bjerkås E, Waagbø R, Sveier H, Breck O, Bjerkås I, Bjørnestad E, Maage A
Norwegian College of Veterinary Medicine, Oslo, Norway.
Acta Vet Scand. 1996;37(3):351-60. doi: 10.1186/BF03548101.
Irreversible bilateral cataracts were diagnosed by slit-lamp biomicroscopy in 178 of 200 farm-raised Atlantic salmon (Salmo salar L) fed a standard diet over a five-month period. Initial changes were anterior polar opacities, progressing to involve both the anterior and posterior cortex before changes in the lens nucleus were seen. The lens changes were recorded and given scores according to the severity of the cataracts. At each of 3 samplings, after 2, 4 and 5 months, 200 fish were measured, weighed and examined by slit-lamp biomicroscopy. At all 3 samplings, there was a significant correlation between body length and both cataract incidence and cataract severity. There was also a significant correlation between body weight and cataract incidence and severity for the 2 last samplings. There was a significant correlation between K-factor as a measure of the shape of the fish, and both cataract incidence and severity, at all 3 samplings. Evaluation of specific growth rate in the periods between the examinations showed that the rapidly-growing fish were most susceptible to cataract formation. After cataract developed, however, the growth rate slowed. Follow-up examination of severely affected fish 3 months after transfer to sea water showed a normal cortical zone in the periphery of the lens in 24 out of 28 fish.
在为期五个月的时间里，给200条养殖的大西洋鲑鱼（Salmo salar L）投喂标准饲料，通过裂隙灯生物显微镜检查诊断出其中178条鱼患有不可逆的双侧白内障。最初的变化是前极性混浊，在晶状体核出现变化之前，逐渐发展到累及前皮质和后皮质。记录晶状体变化，并根据白内障的严重程度进行评分。在2个月、4个月和5个月后的3次采样中，每次对200条鱼进行测量、称重，并通过裂隙灯生物显微镜检查。在所有3次采样中，体长与白内障发病率和严重程度之间均存在显著相关性。在最后2次采样中，体重与白内障发病率和严重程度之间也存在显著相关性。在所有3次采样中，作为鱼体形状指标的K因子与白内障发病率和严重程度之间均存在显著相关性。对检查期间特定生长率的评估表明，生长迅速的鱼最容易形成白内障。然而，白内障形成后，生长速度减慢。将严重受影响的鱼转移到海水中3个月后进行的随访检查显示，28条鱼中有24条鱼晶状体周边的皮质区正常。
