Examination of histological and cytological structure of digestive tract and liver of Spermophilus citellus hibernation and post-hibernation

Spermophilus citellus, taken from their natural environment, were fed and preserved under laboratory conditions during the experiments. Experimental groups in hibernation and after hibernation were dissected under anesthesia, and tissue samples were taken from the liver and small intestine for examination under both light microscopy and electron microscopy. Some changes were observed in the small intestine and liver tissues of S. citellus during and post-hibernation. During hibernation in the small intestine, it was determined that the villi lengths and crypt depths decreased, epithelial cells were fragmented and areas of inflammation (especially around blood vessels) were formed. The decrease in villus length was observed mostly in the duodenum and least in the ileum. In the liver, it was determined that the glycogen particles decreased during hibernation and these particles were found in bulk according to the situation post-hibernation, and the glycogen particles, which were seen as stars post-hibernation, became rounded during hibernation. In addition, during hibernation in the liver, changes such as decrease in the number of glycogen particles around the nucleus and endoplasmic reticulum, shrinkage of mitochondria, deterioration of endoplasmic reticulum structures, increase in kupffer cells, narrowing of the lumen of hepatic veins were detected during hibernation. These changes that occurred in the small intestine and liver during hibernation disappeared post-hibernation.