Effects of Starvation and Refeeding on Liver Structure of Caspian Salmon (Salmo trutta caspius, Kessler1877) Juvenile

The influence of starvation and refeeding on the structure of liver was studied in the juveniles of Salmotrutta Caspius. 480 juveniles were stocked into 12 outdoor concrete tanks (40 fish per tank), with four levels of feeding: full-fed for 6 weeks, 3 weeks starved, full-starved for 6 weeks and 3 weeks starved and 3 weeks fed. The liver was then removed from five individuals taken from each tank (5fish/tank, 3tank/treatment) fixed for 24 h in Bouin´s fixative. The samples were dehydrated through a graded series of ethanol solution up to 100% and xylene, embeded in paraffin, sectioned using microtome at 4μm thickness, stained using haematoxylin and eozin and examined using a Nikon light microscope. The results showed that the starvation influenced significantly the liver structure of the both starved groups as hepatocytes atrophy and reduction of their size (P< 0.05). Cytoplasm was deteriorated and sinus enlargement was observed in the liver of starved fish. In addition, 3-week refeeding could be effective on liver regeneration leading to hepatocytes hypertrophy and increase of their size to the same size of the control group. In conclusion, food deprivation and consumption of energy resources caused tissue damage in the liver structure of Salmo trutta, but refeeding and fulfillment of energy resources may recover tissue damage.