BACKGROUND: Safflower plant can be used in fish due to its antioxidant properties. In the present study, the side effects of intraperitoneal injection of safflower extract in rainbow trout have been investigated. OBJECTIVES: The effect of the intraperitoneal injection of Safflower (Carthamus tinctorius) extract on Aspartate aminotransferase, Alanine aminotransferase and Alkaline phosphatase as tissue damage indicators and also the histopathologic analysis of kidney and liver tissues in rainbow trout (Oncorhynchus mykiss) have been investigated. METHODS: To this end, rainbow trout with an average weight of 100 ±5 gr were supplied and intraperitoneally injected with different levels of Safflower extract. In this regard, one negative control group (with no injection), one positive control group (injected with 0.2 ml normal saline) and three treatment groups (injected with 50, 100 and 200 mg/kgbw of safflower extract, respectively) were considered. Blood samples were taken on the third, seventh and tenth days after injection, in order to isolate blood serums and analyze the ALP, ALATA and ASAT activities. Kidney and liver tissue samples were also taken on the seventh-day post injection. RESULTS: The levels of ALP, ALATA and ASAT activities significantly increased in all treatment groups that received safflower extract compared to control groups in all samples (sig<0.05). In histological analysis typical pathologic effects were recorded in kidney and liver tissue sections. CONCLUSIONS: Intraperitoneal injection of Safflower extract at dosages of 50-200 mg/kgbw led to damage in the liver and kidney tissues, so that the concentration of 200 mg / L had severe histological complications in these tissues. Hence some limitations must be taken into account for using this extract as immune-stimulant or vaccine adjuvant.

BACKGROUND: Silver nanoparticles are now widely used in various industries and consumer products, especially because of their antimicrobial properties. The widespread use of these nanoparticles has increased the likelihood of their release to aquatic ecosystems and their effects on aquatic organisms. OBJECTIVES: The purpose of this study was to investigate the histopathological effects of waterborne silver nanoparticles on the gills of Caspian brown trout. METHODS: In this study, 84 fish (27.46±4.3 g) were tested in four concentrations of silver nanoparticles (0, 0.01, 0.02 and 0.03 mg/L) for 14 days. At the end of the experiment, gill tissue was evaluated to determine the effects of tissue damage caused by silver nanoparticles. RESULTS: Observed tissue damage included hyperplasia, hypertrophy, curvature of secondary lamellae, shortening of second lamellae, separation of epithelium from lamellae and aneurism. CONCLUSIONS: The results of this study showed that colloid silver nanoparticles in water could lead to tissue damage in the gills of Caspian brown trout, and long-term exposure to the sublethal concentrations of these nanoparticles can cause fish death.

BACKGROUND: Tobacco (Nicotiana tobaccum) is a plant with piscicidal and fertilizing properties. OBJECTIVES: In this study the effect of different concentrations (0.1, 1, 10 and 100mg/l) of hydro-alcoholic extracts of tobacco has been examined on different tissues of Rainbow trout. METHODS: Samples from liver, kidney and gill of Rainbow trout were stained with hematoxylin and eosin and studied under light microscopy. RESULTS: Various histopathological lesions were observed in the liver of Rainbow trout exposed to different concentrations of tobacco. The results showed that with increase in concentrations of tobacco up to 10 and 100mg/l, bloodshed increased and hepatocytes lost their continuity and showed discontinuity mood. Lamellar aneurysm, bleeding and leukocytes infiltration, clubbing at the end of the lamellae, hyperplasia of secondary lamellar epithelium, epithelial lifting of secondary lamellae and creating an edematous space, lamellar shortening, vacuolation and lamellar fusion were the more abundant branchial lesions after exposure to tobacco. Separating the epithelium from basement membrane, hypertrophy, glomerular capillary dilation and tubular degeneration were observed in renal tissues in all treatments. At higher concentrations of tobacco (10 and 100mg/l), renal tubular necrosis was also observed. According to the results liver of rainbow trout showed a few histopathological alteration following exposure to tobacco extracts. Unlike the liver, gills of rainbow trout due to direct contact with pollutants showed more lesions. CONCLUSIONS: Tobacco extract has more pathological effects on gills in comparison with liver and kidney of Rainbow trout due to direct contact with the dissolved pollutant.

BACKGROUND: Femoral head osteotomy in cases of fractures or degenerative diseases is as a routine surgical procedure. Less duration of the healing period and the creation of minimal fibrous tissue and its replacement with bone tissue can be effective in return to health. OBJECTIVES: The aim of this study was to evaluate the histopathological changes following administration of platelet-rich plasma at the site of  removed femoral head in rabbits. METHODS: Twenty male New Zealand white rabbits were distributed into two groups including: control (underwent femoral head osteotomy, FHO) and treatment (underwent FHO and planting the platelet-rich plasma on surgical site FHO₊ PRP). In both groups after general anesthesia, femoral head was removed using standard method. In group 2, pre-prepared auto log PRP was used at the site of surgery. After eight weeks all animals were euthanised, femur and its  surrounding healing tissues were cut 2cm  far from the head of femur and removed. Slides were prepared from each sample  through serial sectioning and were stained with H&amp;E and Mason Trichrome. Qualitative changes such as granulation tissues, cartilage and bone formation and their organization and timeliness, thickness of collagen fibers and cellular changes were compared. To quantify the changes, whole surface of the Mason Trichrom stained samples underwent scan with ×50 magnifications and then area of different new formation tissues was measured. Average occupancy levels of each tissue, their ratio to whole surface of sample and to each other in two groups were calculated and compared. RESULTS: In PRP treated group ratio of cartilage tissue to granulation tissue and formation of bone to granulation tissue is significantly more than these parameters in control group. Results indicate faster healing on the damaged area in group 2. Also in group 2, cartilage and bone tissues formation in the healing process was more orderly. CONCLUSIONS: PRP could accelerate healing of bone tissue that is cut at the head of the rabbit’s femur. So it seems that the use of PRP as a treatment protocol in these cases could be suggested.