جستجوی مقالات مرتبط با کلیدواژه "histology" در نشریات گروه "شیلات"

Fishmeal price were increasing every year and predicted that fish diet will have a wider range of ingredients replaced by fishmeal, such as vegetable sources, microbial protein sources, waste from fishing and animal protein waste (Glencross et al., 2007). Vegetable proteins can replace fish meal to some extent and have a negative effect on the growth of aquatic animals at high levels. But many studies have shown that a mixture of vegetable proteins can improve the amino acid profile compared to single protein source replaced by fish meal (Amaya et al., 2007).  By this method, high replacement with a blend of protein Vegetables have been reported in aquatic animal (Hansen et al., 2007), but increasing fiber, increasing carbohydrates and inappropriate amino acids in diets based on animal and vegetable proteins can led to a negative effect on fish digestive system that showed by growth reduction, immune system depress , low quality meat and even fish fatality in a long-term feeding period (Raskovic et al., 2011). therefore, in this experiment, the effect of a mixture of animal and vegetable proteins replaced by fish meal (levels of 20, 40, 60 and 80%) on the growth indices and digestive system tissue Huso huso were studied.

In order to reduce the share of fishmeal in the diet of beluga, a basal diet based on 54% of fishmeal was made. A mixture of animal and vegetable proteins (corn gluten: 35%, wheat gluten: 19.34%, processed soybean flour: 3%, chicken by-products: 20%, meat and bone meal: 8%, blood meal: 3.4%) at 20, 40, 60 and 80% levels replaced with fishmeal (FM) (CGM20, CGM40, CGM60, and CGM80, respectively) and finally 5 isonitrogenous (44% crude protein) and isoenergetic (18 MJ/kg) diets were produced. The fish (Average weight: 167±6.5 gr) were fed to saturation for 12 weeks.  Biometry were carried out on month interval and by carrying out information obtained from fish length, weight and food consumption, growth indices and feed efficiency ratio were calculated. At the end of the feeding period, 30% of the fish population was collected from each tank for histological studies. Three parts of the intestine (hindgut, midgut, and foregut) were removed. It was fixed and stained. Histological studies were carried out by an optical microscope equipped with a monitor.

There was no significant difference in the final weight and length of fish of different treatments (P>0.05). condition factor and percentage of weight gain of fish fed with FM, CGM20, CGM40, CGM60 and CGM80 had no no significant difference and percentage of weight gain was close to each other (243 to 298%) (P>0.05). No significant difference was observed in specific growth rate and daily growth rate and food conversion ratio in fish fed with all diets (P>0.05). Fish fed FM had the highest protein efficiency ratio (1.75±0.23), but protein efficiency ratio in fish fed with CGM20, CGM40, CGM60 and CGM80 was in the range of 1.53 to 1.73%. But no significant difference was observed (P>0.05). Histological studies were carried out by an optical microscope equipped with a monitor. The intestinal tissue of fish fed with CGM80 diet had necrosis and biliary stagnation. However, histological studies in fish fed with FM, CGM20, CGM40, and CGM60 diets showed that the lamina propria space is adequate, the necrosis of enterocytes is negligible, and the number of goblet cells in the anterior, middle, and distal intestine is balanced. The final results confirmed that the CGM80 did not a negative effect on the growth fish, but it caused damage to the digestive system.  In the present study, there is no significant difference in growth indices and food conversion ratio of fish fed with diets based on fish meal and diets based on corn gluten flour (a mixture of corn gluten: 35%, wheat gluten: 19.34%, soybean meal processed: 3%, poultry by product: 20%, meat and bone meal: 8%, blood powder: 4.3%). In this order, it seems be that alternative diets formulation based on a mixture of Animal and vegetable protein sources  were led to enriching of profile and biochemical composition of diet, In addition beluga Compared to white and Siberian sturheon is a species that can be fed with high carbohydrates percentages without growth reduction (Mohseni et al., 2011). In the present experiment, by increasing mixtures based on corn gluten-based in fish diet,  goblet cells were increased and reached to highest value in CGM80. goblet cells are related to immune system and mucus secretion in order to fluidity of digestive tract and create a protective barrier against mechanical and chemical damage (Marchetti et al., 2006). it seems that the increase of goblet cells in beluga fed with a mixture of vegetable proteins (CGM60 and CGM80) is a reaction against to mucous layer necrosis and reduction of intestinal villi in order to further damage of folds by secreting more mucins (Li et al., 2007), but in general, digestive tract epithelium damage in fish fed CGM20, CGM40 diets and CGM60 was negligible compared to fish fed with FM diets and did not lead to enteritis (intestinal inflammation). Therefore, it is suggested to replace fishmeal with a mixture of animal and vegetable proteins at 20 and 40% in Huso huso diet during the fattening stage.

The aim of this study was to evaluate the effect of different levels of organic and mineral sources of selenium on the intestinal morphology and also histologically changes in liver tissues of juvenile rainbow trout for 60 days. For this purpose, 1080 healthy fry fish (50±2.8 g average body weight) were randomly divided into 3 groups, including organic selenium (0.15, 0.30, 0.45, 0.60 mg. kg-1), mineral selenium (0.15, 0.30, 0.45, 0.60 mg. kg-1) and a control group with triplicates. At the end of trial, 3 fish were caught in each treatment. After anesthesia, the fish were autopsied. The liver and intestine of fishes were removed and histologically studied by standard tissue procedures. Finally, prepared tissues were evaluated by optical microscopy. The microscopic and morphometric results indicated a significant improvement in the morphological changes of the intestinal tissue including the auxesis of absorption area, length and diameter of villi and abate of depth of villi crypt in treatment containing 0.45 mg. kg-1 organic selenium of diet compared with other treatments and control group (p<0.05). Also, the least histopathological changes of liver tissue in the treatment containing 0.45 mg. kg-1 organic selenium in diet and the most extensive lesions wereobserved in both the control group and higher levels of dietary mineral selenium. It seems that, the treatment containing 0.45 mg. kg-1 organic selenium in diet were identified as the best supplement for improving of the intestinal tract and decrease in possible histopathological side effects in rainbow trout.

Troxerutin, a derivative of the natural bioflavonoid rutin, has important biological effects, including immunostimulatory activity. This study aimed to evaluate the effects of dietary troxerutin supplement on histology and mRNA expression of the genes encoding lysozyme and tumor necrosis factor-α in goldfish, Carassius auratus skin. Fish fingerlings with mean initial weights of 2.74 ± 0.08 g were fed diets supplemented with 0.1, 0.3, 0.5 g troxerutin per kg feed for 80 days. For histological studies, skin from right side and near dorsal fin (0.5cm) was dissected and stored in 10% formalin buffer. For molecular assay on skin tissue, RNA extraction, cDNA synthesis, and real time PCR were performed. Histology results showed a significant increase in alarm cell density in the treatment groups compared to the control group (P<0.05). Alarm cell volumetric ratio to epidermis was significantly higher in the treatment groups, with highest level in fish administrated with medium and high dose of troxerutin, in comparison with the control group (P<0.05). Epidermis thickness did not show significant changes in comparison with the control group (P>0.05). Molecular assay results showed more increase in mRNA expression of the genes encoding lysozyme and tumor necrosis factor-α in the treatment groups, with the highest level in the high dose group, in comparison with the control group (P<0.05). The results indicate that feeding troxerutin at 0.5 g per kg feed has a potential to enhance histology indices and mRNA expression of the genes encoding lysozyme and tumor necrosis factor- α in goldfish (Carassius auratus) skin.

Panax ginseng (P. ginseng) root as a traditional herbal medicine, has biological capabilities e.g. antioxidative and detoxification, although there is little data about its probable effects on the liver structure particularly in the aquatic organisms. So, the present study was aimed to investigate the effects of different levels of aqueous extract of P. Ginseng root on the hepatic histomorphometric properies (the area of the hepatocytes and nuclei, perimeter of hepatocytes, percentage area of the hepatocytes, nuclei and hepatic sinusoids, number of küppfer cells/unit area) and some serum biochemical parameters of Rainbow trout. Study carried out during 60 days within 4 experiments, each with 3 replicates. In each replication 60pcs of fry with average weight of 15gr. were randomly distributed. Experiments were fed with aqueous extract of P. Ginseng at 100, 150 & 200 gr./kg. diet. Hepatic tissue and blood samples were taken at the end of the study. The results showed that different levels of Ginseng had no significant effect on the histomorphometric parameters of hepatic parenchyma (P>0.05). Serum levels of Cholesterol. Albumin and Total protein decrease significantly in the Ginseng treated fishes (P<0.05) in comparison to control group. There was no significant difference between AST, ALP, and ALT with control (P>0.05). Total serum LDH in groups II and III showed a statistical significant increase with control (P<0.05). These findings showed that addition of Ginseng extract in concentrations up to 0.2% diet in rainbow trout fry feeding, can be considered as a probable growth promoter without negative effects on the hepatic structure.

The aim of the present study is to investigate the growth performance and sexual maturation process of female rainbow trout reared in a cage in the Caspian Sea (Mazandaran- Nowshahr). Rainbow trout with an average weight of 122± 5 g were stocked into a cage located in Caspian Sea. Fish were fed daily and random sampling was done monthly (January 2015) to May 2016. Weight and length of thirty fish were measured; their gonad and liver were weighted; total length, total weight, liver and gonad weight, condition factor, GSI and HSI and oocyte diameter were calculated; their blood samples were collected and the levels of 17 beta estradiol, testosterone, progesterone and the vitellogenin were measured; also gonad tissue samples were prepared and examined using a light microscope. The results showed optimal somatic and gonadal growth of fish caged in the Caspian Sea. Sex hormones and vitellogenin levels increased significantly (P<0.01) during the study period. The levels of 17 beta estradiol, testosterone and progesterone in January were 0.56± 0.05 ngml-1, 0.50± 0.05 ngml-1and 0.14± 0.01 ngml-1 respectively and reach to 1.63± 0.13 ngml-1, 0.80± 0.01 ngml-1 and 0.28± 0.03 ngml-1 in May, respectively. Vitellogenin levels increased from 382.40± 55.26 ngml-1 in January to 651.40± 86.34 ngml-1 in May. The gonads developed to stage 4 and the oocyte diameter increased significantly (P<0.01) during the study period. The findings of present study show that female rainbow trout are able to have appropriate somatic growth in the brackish water of the Caspian Sea like fresh water, and the natural process of sexual maturation won’t be disturbed.

The current study was carries out to determine the effect of fish meal replacement with Aqupro on growth, blood indices and liver enzymes activities in fingerling rainbow trout. Number of 540 fish (18 g) were randomly distributed in 18 fiberglass tanks (250 l capacity) and five isoproteic diets were formulated. The fish meal inclusion reduced from 50 percent in diet one to 10 percent in diet five. After three months feeding trial, growth, blood indices, liver and intestine histology as well as liver enzymes activity were analyzed. Fish meal reduction and increasing Aqupro levels, had no negative effect on growth parameter. The FCR, FER and SGR had no significant differences between groups.  In case of blood indices, the number of white blood cells was significantly higher in group five. Ht, Hb and RBC were significantly higher in second group. Albumin had no differences between treatments. AST and ALT is the fifth group were higher than others while ALP was higher in the control group. No damage and disfunction was seen in the liver and different part of intestine in response to addition of Aqupro.

Copper (Cu) is an essential micronutrient in animals for normal growth and development of bones, connective tissue, the heart and several other organs, since around 30 enzymes are known to use copper as a cofactor. The commercial diet should provide the essential amount of Cu, which depends on the physical and chemical properties of the form of the supplement in which the Cu is given in the diet. However, the feed industry still prefers CuSO4 for economic reasons. Thus this study was conducted to evaluate the effects of different sources of copper (Cu) on digestive enzymes activity and pathological alterations in goldfish, Carassius auratus. The five experimental diets were formulated to contain different levels of Cu-NPs (0, 3, 5 and 10 mg/kg) and 3 mg/kg CuSO4 and given to goldfish (initial average weight and length 7.78 ±0.67 g and 5.86 ± 0.43 cm respectively) for 8 weeks. Intestinal protease and lipase activities increased and amylase decreased by Cu-NPs compared with the control group (p<0.05). In this study, feeding goldfish with CuSO4 led to significant pathological alterations in intestinal tract. The overall result recommends adding 3 mg Cu-NPs per kg diet improve health and intestinal digestive where the same dose of CuSO4 induce intestinal tract negative impacts in goldfish. However, further studies are needed to explain the molecular mechanisms of Cu-NPs as well lower concentrations of CuSO4.

Nowadays, the presence of microplastics in aquatic ecosystems is a serious challenge for aquatic animals. In this study, the accumulation of polystyrene microplastic (PS-MPs) and its toxic effects on histology of liver and intestines of goldfish was investigated. A total of 231 healthy fish with an average weight of 18.55±2.41 g was selected in the spring of 2019. Microplastic were synthesized in two size ranges (0.25 and 8 μm) with two different functions (fluorescent and non-fluorescent). The experiments were performed in two stages. Initially, after the adaptation period, 68 fish were exposed to a constant concentration (PS-MPs) of 300 µg/L of both 0.25 and 8 μm PS-MPs. Liver and intestinal tissue were sampled for 7 days and the samples were imaged using a fluorescent microscope. Then, 168 fish were exposed to non-fluorescent microplastics with different concentrations (0, 5, 0.5, 0.05 ppm) for 28 days to determine histopathological lesions. The results showed that both sizes can accumulate in liver and intestinal tissues. Examination of liver histopathology showed different complications such as bleeding, necrosis, cell swelling, bile stasis, thinning of the sinusoidal space and accumulation of blood compared to the control group, the severity of lesions increased with increasing concentrations in a group of size. There was no predictable trend, but the intensity of destruction was greater at 0.25 μm. Examination of intestinal tissue lesions showed different complications such as necrosis, loss of intestinal villi, vacuolation, villi decay and degeneration of epithelium in both size groups compared to the control group. In general, microplastics have destructive tissue effects on goldfish. Most tissue lesions were observed at the highest concentration (5 mg/l). The severity of particles with a size of 0.25 μm was higher than the size of 8 μm, with destructive effects observed first in the intestine and then in the liver.   

Today, the replacement of plant extracts instead of chemical preservatives in the diet has been considered with reducing the adverse effects of chemical preservatives. In this study, the effects of black grape seed extract on growth, intestinal and liver histology, as well as gastrointestinal enzymes, in common carp were investigated. Grape seed extract (30g kg-1) was added to the basal diet and at the end of the experimental period, the digestive enzymes, including lipase, amylase, and trypsin, were measured. The fish were also dissected, then intestine and liver were collected and fixed for histological studies. The results showed that among different digestive enzymes, only lipase had a significant increase (1.67±0.10 U/mg protein) compared to control group (1.35±0.04 U/mg protein). In the intestinal and liver histology, supplemental diet did not have any side effects on the normal structure. The ratio of villus height to the distance between two adjacent villus in the basal part was slightly higher in treated fish (17.39 ± 0.5μm) than the control group (16.71 ± 0.59 μm), but no significant differences was observed. Also, the number of goblet cells in control group (4.59±0.17μm) was slightly higher than treated fish (4.09±0.21μm), however, no significant difference was observed. Morphometric study in liver also showed an increase in hepatocyte size (24.01±0.16µm) compared to the control group (23.42±0.14µm). In general, the increase of the digestive enzyme activity and healthy liver and intestine structure could show the potential of grape seed extract as a beneficial feed additive in common carp.

This study aims to assay the main protease (pepsin and trypsin) activity and pepsinogen relative gene expression, as well as histological development of digestive tract in Sobaity from hatching up to 40 days post- hatch (DPH). The results showed that exocrine pancreas, including zymogen granules, differentiated during yolk sac absorption and further developed at 14 DPH. The early appearance of trypsin before mouth opening is attributed to a genetically programmed process. The trypsin activity showed fluctuated pattern (with two peaks at 16 and 30 DPH), coincident with food intake, and related to diet shifting during larval feeding. The most obvious differentiation in the digestive tract was the formation of an incipient stomach surrounded by striated muscle fibers and the development of the gastric glands at 12 DPH. The stomach fully developed at 25 DPH with the transition from striated to smooth muscle cells. The pepsinogen relative gene expression was not detectable before 12 DPH and meaningfully detected at 14 DPH. The pepsinogen expression augmented exponentially coinciding with shifting diet from live to microdiet. Pepsin activity trend was considerably parallel to pepsinogen and started two days after pepsinogen, subsequently increased sharply during the weaning period (25-30 DPH) up to the end of the study. The study concluded that the appearance of the incipient stomach at 12 DPH, early pepsinogen expression, and ontogenetic development of pepsin and trypsin, make it possible to feed Sobaity larvae by inert diet before 25 DPH to reduce the live food consumption and improve the weaning efficiency.

The purpose of this study was to investigate the effect of replacement of copper sulfate with nano oxidase in diet on growth and survival, enzymatic activity and pathology of liver tissue of goldfish in 2018.

Experimental treatments consisted of 5 control treatments, 3 mg / kg copper sulfate; 3 mg / kg nano-oxide, 5 mg / kg nano-oxide and 10 mg / kg nano-oxide, and fish were given 4% by weight twice a day for 60 days. The body was fed manually. At the end of the trial period, growth and survival indices , liver enzymes activity (alkaline phosphatase, aspartate transaminase, alanine, Aminotransferase) as well as liver tissue pathology were evaluated.

Based on the results, using copper nanoparticles at different levels of 3, 5 and 10 mg / kg diet instead of copper sulfate in the diet can improve the growth performance and survival of goldfish. Copper sulfate also has more negative effects on liver tissue than nanoparticles, as well as alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase enzymes; therefore, the replacement of copper sulfate with copper nanoparticles in the diet seems to reduce the effects of water. On the other hand, histopathological results of liver tissue treatment with 5 and 10 mg Cu / kg diet showed that Cu nanoparticles cause tissue lesions and deleterious effects (albeit less than copper sulfate).

Copper sulfate with copper nanoparticles at levels of 3 mg / kg diet To be carried out.