Comparative Histological Observation of Liver Tissue Before and After Reproduction in Male and Female Frogs (Pelophylax ridibundus)

Abstract

Histomorphological structure of the liver of Ranidae species during the reproduction period contribute significantly to the production rate in the frog culture studies. In this study, the cytoplasmicstatus of hepatocytes, lipid and melanin pigment in liver parenchyma of adult male and femalePelophylax ridibundus (Pallas, 1771) were investigated before and after reproduction. For histological studies, adult frogs were collected from nature and placed in production ponds to examine the reproduction process. In this study, twenty four breeding male frogs, with average weight36.63±12.84 g and length 69.29±9.15 mm, and twenty four breeding females with average weightand length of 56.61±19.59 g and 79.54±7.07 mm were used. Samples from the liver tissue of frogwere taken in 2015 during (March) and after reproduction (June) period. Histologically pictures ofliver parenchyma were taken from the as homogeneous fields as possible. Before the reproduction, it was found that the liver parenchyma of the female frogs were cytoplasmically intense, witha low amount of melanin pigment and lipid droplets. Similarly, male frogs liver parenchyma andhepatocytes were found to be cytoplasmically intense, containing a low amount of melanin pigment and lipid droplets. Both female and male frogs completed the reproduction in April andMay. After reproduction period, a great amount of melanin pigment in the liver parenchyma wasobserved and the cytoplasmic density of the hepatocytes decreased. As a result, cytoplasmicdecrease in hepatocytes, structural changes and increase in melanin pigments supports the ideathat glycogen and lipids stored in the liver parenchyma are used for reproduction.