Solovyev Mikhail, Shokurova Anastasiya, Kondakova Ekaterina, Vasilenko Vadim, Bochkarev Nikolai, Kashinskaya Elena, Gisbert Enric
Institute of Systematics and Ecology of Animals SB RAS (ISEA), Novosibirsk, 630091, Russia.
Tomsk State University (TSU), Tomsk, 634050, Russia.
Fish Physiol Biochem. 2025 Jan 18;51(1):34. doi: 10.1007/s10695-024-01440-4.
The effect of different feeding habits on gut morphology and digestive function has been intensively studied during the last decades but sympatric closely related fishes are relatively rare objects of such studies. In the present study, we have identified both morphological and physiological changes in the digestive system of a sympatric pair of whitefish represented by "normal" Coregonus lavaretus pidschian (benthivorous) and "dwarf" C. l. pravdinellus (planktivorous) forms. There were statistically significant differences in terms of histometric variables between segments of the stomach (height of lining epithelium, fold thickness and height values, and number of folds) and intestine (enterocyte height and fold height) within each form as well as between forms for the same segment of the digestive tract like in the stomach (height of lining epithelium and fold thickness) and intestine (enterocyte height, fold height and fold thickness). Both forms had a similar number (8-9 bands) and molecular weight of isoforms/isoenzymes of alkaline proteases inhibited by PMSF (serine proteases) based on zymogram analyses. The maximum level of activity of alkaline proteases, alkaline phosphatase, and aminopeptidase N were registered in the pyloric caeca for both forms. In contrast to these enzymes, the activity of α-amylase as well as of non-specific lipases and esterases in the pyloric caeca was similar or even lower if compared to other intestinal segments. In conclusion, both sympatric forms of whitefish showed some similarities in several of studied biochemical and histological parameters of their digestive tracts, regardless of their different feeding habits, which might be related to their genetical background.
在过去几十年中，人们对不同摄食习性对肠道形态和消化功能的影响进行了深入研究，但同域分布的近缘鱼类相对较少成为此类研究的对象。在本研究中，我们确定了同域分布的一对白鲑消化系统的形态和生理变化，这对白鲑分别以“正常”的拉氏白鲑pidschian（底栖食性）和“矮型”的拉氏白鲑pravdinellus（浮游生物食性）为代表。在每种形态的胃各段（内衬上皮高度、褶皱厚度和高度值以及褶皱数量）和肠道（肠细胞高度和褶皱高度）之间，以及在消化道同一节段（如胃的内衬上皮高度和褶皱厚度以及肠道的肠细胞高度、褶皱高度和褶皱厚度）的不同形态之间，组织测量变量存在统计学上的显著差异。基于酶谱分析，两种形态的受苯甲基磺酰氟（丝氨酸蛋白酶）抑制的碱性蛋白酶同工型/同工酶的数量（8 - 9条带）和分子量相似。两种形态的碱性蛋白酶、碱性磷酸酶和氨肽酶N的最大活性水平均在幽门盲囊中测得。与这些酶不同，与其他肠段相比，幽门盲囊中α -淀粉酶以及非特异性脂肪酶和酯酶的活性相似甚至更低。总之，同域分布的两种白鲑形态在其消化道的一些研究生化和组织学参数上表现出一些相似性，尽管它们摄食习性不同，这可能与其遗传背景有关。
