جستجوی مقالات مرتبط با کلیدواژه "معده" در نشریات گروه "زیست شناسی"

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.

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.

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.

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.

Today, microplastics are among the most important environmental pollutants that have attracted the attention of scientists. These plastic particles enter the food chain by being swallowed by animals and cause serious damage to humans and animals. The purpose of this research is to investigate the effect of polystyrene microplastics on the digestive system of mammals. The rats were divided into 3 groups of 6; the sham group received 200 microliters of distilled water once a day for 30 days. The first group received 200 microliters of nano-styrene once a day with a dose of 0.1mg⁄kg for 30 days. The second group received 200 microliters of nano-styrene once a day. He received a dose of 0.5 mg⁄kg for 30 days. The day after the last gavage, the animal was anesthetized with chloroform, and the intestinal and stomach samples were stained for histological examination in 10% buffered formalin solution with hematoxylin-eosin staining method. TUKEY test was used for statistical analysis and comparison between groups. All the calculations were done using Prism software and the significance level of the tests P was considered less than 0.05. The statistical findings show a decrease in the diameter of the submucosa, the number of lining cells, and the number of epithelial cells in the experimental group 2 compared to the control group. The height of the intestinal villi and The stomach showed an increase in experimental group 2 compared to the sham group. The results of this study show that the effects of nano-styrene depend on the concentration and as the concentration increases, it will leave more destructive effects on the intestines and stomach.

Bats play a special role in the earths ecosystem by eating harmful insects, helping in pollination of trees and producing precious fertilizer. Due to their ecologic and economic importance, and to get a better understanding of bats, the differencebetween histology of gastric tissue in two species of bats namedRhinopoma hardwickii and Rousettus aegyptiacusis studied. In this research five insectivorous bats and five flying fox were chosen from Jahrom in the province of Fars, tissues of their stomach were prepared, and sections were compared regarding presence or absence of perez, type of muscle cells, type of glands, type of gland secretions, types of cells, existence or lack of serous membrane, and presence or absence of pits were examined by light microscopy.The results showed that the stomach tissue in both species were similar to mammals and had 3 areas: cardia, body and pylorus; however, the lining mucosa and sub-mucosa in fruit-eating species were thicker and specific and had more collagen fiber than the insectivorous species. Based on the present study, in general, the stomach layers in flying fox species are thicker than that of Insectivorous bats; that is probably because of bigger stomach of flying fox comparing with the insectivorous species which is probably due to the greater size of the stomach in flying fox species which is due to the necessity of more time for digesting the cellulosic materials in flying fox species stomach.