1.
The present study was carried out for the first time to analyze the morphological and functional state of
hepatopancreas in P. spinigera with different dietary vitamin A level. The study evaluated the growth and changes in the cytomorphology of hepatopancreatic cells. The functional histology was carried out at the (1) Initial period, after (2) 30-35 days, (3) 60-65 days and (4) 90-95 days of administration with control diet. Starting from the early period of deficiency, degeneration of nucleus and haemocytic cells and reduced lumen diameter of the tubules were observed. It has been found that after 90-95 days, the hepatopancreatic epithelium is highly affected and there are several histopathological lesions leading to metaplasia and keratinization of normal columnar epithelium to squamous nature with necrosis of mucous glands.
1.
Effects of deprivation of vitamin a on the intestine of paratelphusa spinigera wood mason
This study shows the effect of vitamin A deprivation in the epithelial tissues of the intestine of Paratelphusa spinigera, a fresh water crab. Histological studies were conducted both in control or normal and vitamin A –deficient crabs. The administration of vitamin A –deficient diet was continued for 90-95 days and chronological studies were done at 30-35 days, 60-65 days and 90-95 days and the histopathological changes were analyzed. Gradual degeneration of mucous glands leading to metaplasia and keratinization of columnar epithelial cells to squamous type, atrophy of villi with congestion of blood vessels in the serosal layer were observed in acute deficiency of vitamin A. These results also suggest that a decrease in the level of vitamin A may have a detrimental effect on the intestinal epithelium of the crab.