Deficiency of thiamine (vitamin B₁) has been demonstrated in several species in the northern hemisphere and is suggested as a cause for declining populations. European perch from the Baltic Sea show negative temporal trends for several health biomarkers and poor recruitment of unknown cause. In this study, thiamine status of perch liver from the Baltic Sea was studied with emphasis on seasonal variation. During spring the thiamine concentration increased, reached a higher level during the summer and then decreased again during autumn. Despite this variation the thiamine concentration was always sufficient in the perch liver. These results indicate that direct thiamine deficiency is an unlikely explanation for the health effects observed in adult female perch from the Baltic Sea.

在北半球的几个物种中已经证明硫胺素（维生素 B ₁）缺乏，并被认为是导致种群下降的原因。来自波罗的海的欧洲鲈鱼显示出几种健康生物标志物的负时间趋势和未知原因的不良招募。在这项研究中，重点研究了波罗的海鲈鱼肝脏的硫胺素状况，重点是季节性变化。在春季，硫胺素浓度增加，在夏季达到较高水平，然后在秋季再次下​​降。尽管有这种变化，鲈鱼肝脏中的硫胺素浓度总是足够的。这些结果表明，直接缺乏硫胺素不太可能解释在波罗的海成年雌性鲈鱼中观察到的健康影响。