Cell and Tissue Journal

Abstract Aim: The use of algae as a food additive has many positive effects such as increasing the quality, health, and greed of food and increasing the level of growth and immunity in aquatic animals. Among the algae with many uses are the members of the red algae branch, which are seen in red due to the large amounts of phycoerythrin and phycocyanin pigments. These algae belong to primary multicellular plants of the marine species, non-flowering without roots, stems, and leaves, and they reproduce sexually. The current research was conducted to replace red algae in the diet in stomach, liver histomorphology, and some growth factors of Nile tilapia, one of the most important commercial species in the world.
Material and Methods: For this purpose, after 8 weeks of preparation, fish were fed diets containing zero, 3%, 6%, and 9% of food weight with red algae with three repetitions in each treatment. After the end of the rearing period, the fishes were anesthetized and after opening the abdominal area while measuring some growth factors, a 0.5 cm tissue sample was taken from the middle part of the stomach and liver and placed in a 10% formalin buffer solution. After going through the routine steps of tissue preparation, including dehydration with alcohol, clarification with xylol, blocking with paraffin, cutting with a thickness of 4-6 microns, and staining, finally, the study was done with a light microscope. SPSS software version 21 was used for statistical analysis of data.
Results: Microscopic and anatomical studies of the stomach and some growth factors of the digestive system showed an increase in the measured factors as percentage of weight gain, especially in the group receiving the diet containing 9% red algae. The results of microscopic studies on the stomach showed that the mucosal lining of the stomach is of a simple type with nuclei near the base. This tissue is stretched from the surface of the mucous membrane to the inner part, so that at the beginning of the stomach, short but deep folds were also observed at different intervals. In the lamina propria of gastric mucosa, simple tubular glands were observed, whose tissue consists of a row of short cubic to cylindrical cells, which have spherical to elongated nuclei and basophils attached to the base of the cells. These cells had strong acidophilic color and covered all the lamina propria. Also liver was completely lobulated and the pancreas was located in the form of an appendix gland inside.
Conclusion: The results of this research showed that in terms of the structural characteristics of the stomach and liver tissue such as mucous glands, epithelium thickness, thickness, mucus height, and anatomical growth of the digestive system, red seaweed powder can be a suitable substitute for fish meal in the diet. Tilapia, along with possible substitutes in other animal and vegetable proteins, can be used to feed this fish, which will eventually reduce the cost and reduce the dependence on fish powder to supply the protein needed by Nile tilapia.

Abstract Aim: The main purpose of the recent study was to evaluate gill chloride cells in Cyprinus carpio during adaptation to different environmental salinities over a short period.
Material and Methods: For this research, Cyprinus carpio by an average weight of 41.4±1 g and length of 16.9±1 cm in four groups with three replications was used. The first group as control was located in fresh water and the next three groups respectively were kept in 4 ppt, 8 ppt, and 12 ppt salinity with the exact condition. On 0, 6, 12, 24, 48, 72, and 96 h the second-gill arch with a maximum thickness of 0.5 cm from the left side was prepared and placed in formalin’s buffer 10%, glutaraldehyde 2.5% solution, and pH 7.4. Then the standard method of preparing tissue sections was performed and paraffin sections with a thickness of 4-6 microns were prepared and stained with hematoxylin and eosin methods and examined with a light microscope. Also, changes in the structure and number of mitochondrial-rich cells, distribution, and dispersion of Na+/K+-ATPase enzyme were studied by scanning electron microscope and immunohistochemical technique.
Results: Results showed obvious modifications in the number and distribution of chloride cells in two filament and lamellar positions at different sampling times. The highest number of chloride cells in the filament and lamella, 26.28±1.33; 19.11±1.27 was reported in 12ppt and the lowest number belonged to the control group. The largest size of chloride cells in the filament and lamella, 22.51±1.56; 12.72±1.32 was reported in 12ppt and the lowest size belonged to the control group.
Conclusion: The findings of this study showed that C. carpio gill chloride cells in the face of different salinities in a short period can change the number and size and adapt to the new condition.

Abstract Aim: Hepatopancreas as a vital organ whose function changes during life, effects clearly on histological structure. Since there is no study about this matter this study has been done.
Material and Methods: In this study fifty healthy mature vannamei with the average length of 12±1 cm and weight of 18 ± 0.5 gr were caught from breeding farms. After adaptation, shrimps were kept in two aquavarium with same condition while one group was kept hungry for 5 days and another group (control group) was fed during the same time. Then 20 hepatopancreas from each group were taken and held in Davidson solution fixative. The routine procedures of preparation of tissues were followed and the cutted paraffin blocks were stained, and studied under light microscope.
Results: Microscopic findings, revealed kinds of M, E, B and R cells. The number of cells, size of lobules and the weight of hepatopancreas in non-hungry and hungry samples were measured and examined with statistical analysis. Results showed reduce in number and area of hepatopancreas tubules especially in resorptive cells than to other cells.
Conclusion: According to the findings, weight and area of hepatopancreas, size of cells and tubules in two groups was significance with statistical analysis.