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Microalgae are a highly effective and renewable source of biodiesel that can be used as a substitute for petro-diesel in the global fuel market. In the present study, 14 water samples were collected from a variety of locations along the coastal areas of the Red Sea and the Mediterranean Sea in Egypt. These water samples, which contained microalgae, were subjected to enrichment process and standard procedures to obtain pure cultures. Based on morphological features, 27 microalgae isolates representing 12 different species were identified, with Chlorella species being the most dominant. Based on 18s rRNA gene sequencing, nine new native microalgae strains were identified, comprising four strains belonging to Chlorella species, two strains to Chlamydomonas, and one strain each of Phormidium, Nostoc, and Microcytosis species that could be appropriate for producing biodiesel. This information could be used to improve the knowledge on the composition of planktonic microalgal communities of Egypt and the target native species for biodiesel production. [ABSTRACT FROM AUTHOR]

Simple Summary: Fatty liver injury is common in farmed fish, but its molecular mechanisms are not well understood. An eight-week feeding trial was conducted to investigate the effects of dietary chitosan on high-fat diet (HFD)-induced liver damage in Nile tilapia. Six diets with varying fat and chitosan levels were tested. Fish on the HFD showed increased growth, fat accumulation, elevated liver injury markers, and higher levels of pro-apoptotic and inflammatory markers. Chitosan supplementation mitigated these effects and reduced intestinal injury by improving antioxidant defense and reducing inflammation and apoptosis through the nrf2 and cox2 pathways. Fatty liver injury is a prevalent condition in most farmed fish, yet the molecular mechanisms underpinning this pathology remain largely elusive. A comprehensive feeding trial spanning eight weeks was conducted to discern the potential of dietary chitosan in mitigating the deleterious effects of a high-fat diet (HFD) while concurrently exploring the underlying mechanism. Growth performance, haemato-biochemical capacity, antioxidant capacity, apoptotic/anti-apoptotic gene expression, inflammatory gene expression, and histopathological changes in the liver, kidney, and intestine were meticulously assessed in Nile tilapia. Six experimental diets were formulated with varying concentrations of chitosan. The first three groups were administered a diet comprising 6% fat with chitosan concentrations of 0%, 5%, and 10% and were designated as F6Ch0, F6Ch5, and F6Ch10, respectively. Conversely, the fourth, fifth, and sixth groups were fed a diet containing 12% fat with chitosan concentrations of 0%, 5%, and 10%, respectively, for 60 days and were termed F12Ch0, F12Ch5, and F12Ch10. The results showed that fish fed an HFD demonstrated enhanced growth rates and a significant accumulation of fat in the perivisceral tissue, accompanied by markedly elevated serum hepatic injury biomarkers and serum lipid levels, along with upregulation of pro-apoptotic and inflammatory markers. In stark contrast, the expression levels of nrf2, sod, gpx, and bcl-2 were notably decreased when compared with the control normal fat group. These observations were accompanied by marked diffuse hepatic steatosis, diffuse tubular damage, and shortened intestinal villi. Intriguingly, chitosan supplementation effectively mitigated the aforementioned findings and alleviated intestinal injury by upregulating the expression of tight junction-related genes. It could be concluded that dietary chitosan alleviates the adverse impacts of an HFD on the liver, kidney, and intestine by modulating the impaired antioxidant defense system, inflammation, and apoptosis through the variation in nrf2 and cox2 signaling pathways. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of dietary inclusion of chitosan (CTZ) on semen variables, sperm apoptosis and DNA fragmentation, and seminal plasma antioxidant status of Zaraibi goat bucks fed high-fat diet.Total of 15 mature bucks (39.42±0.48 kg LBW and 18-30 mo old) were divided into 3 groups (n= 5); the control (CG) and two of the groups received the control diet in addition to2.5 g CTZ/kg concentrate (CTZ) or 2.5 g CTZ+30 g dry fat diet/kg concentrate(CTZ+FAT), respectively for 8 weeks. Results showed that ejaculate volume, percentages of progressive motility, livability, and abnormality of spermatozoa, sperm concentration, as well as sperm counts (total, motile, live, normal and functional) per ejaculate were improved (P<0.05) by CTZ-diet. CTZ+FAT diet improved (P<0.05) all previous traits, except percentage of sperm abnormality. The viable sperm percentage was higher (P<0.05), while the percentage of necrotic spermatozoa was lower (P<0.05) with CTZ or CTZ+FAT diets. apoptotic spermatozoa percent was not affected significantly by treatments. The percentage of sub G1 was decreased (P<0.05) while haploid percentage increased (P<0.05) by CTZ and CTZ+FAT diets. The diploid and spermatid percentages were not affected by CTZ. Peroxidation marker (MDA) was decreased (P<0.05) while activity of GSH, CAT, and GPxwereincreased (P<0.05) by CTZ alone. CTZ+FAT dietrestore (P<0.05) the depleted levels of antioxidant enzyme and MDA to their values in CG. Serum testosterone did not differ, but testosterone level was higher (P<0.05) in CTZ than in CTZ+FAT in the seminal plasma. Insignificant differences in serum total protein, albumin, globulin, and urea concentrations while serum activity of AST and ALT was significantly (P<0.05) increased by CTZ+FAT treatment as compared to CG. The dietary chitosan supplementation at a level of 2.5 g/kg for 8 week-interval pre-semen collection has a vital role on scavenging the negative effects of oxidative stress in the seminal plasma of bucks fed control or high-fat diets. Thus, chitosan could be safely used in Zaraibi buck's diets to improve semen quality and antioxidant defense system and to potentiate the reproduction of goat males. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the effect of Ulva fasciata methanol extract (UFME), as a dietary supplement on growth performance and growth‐related gene expression in liver, intestinal morphometry, haemato‐biochemical profile, immune response and oxidative status of Nile tilapia (Oreochromis niloticus). Four triplicate groups (Control, UFME50, UFME100 and UFME150) of fish (initial weight=1.32 ± 0.12 g, N = 180) were fed with 4 dietary inclusion levels: 0, 50, 100 and 150 mg kg−1 UFME respectively, for 3 months. Results showed non‐significant improvement in the growth performance of fish. Growth hormone gene expression was upregulated in UFME100 fish (p < 0.05). Histomorphometrical assessment of intestinal villi absorptive capacity revealed an improvement in villus length and goblet cell number in fish fed UFME specially UFME100 (p < 0.05). UFME100 showed higher haematological parameters (p < 0.05). Antioxidant enzyme activities of superoxide dismutase (p < 0.05) and catalase (p > 0.05) were induced by UFME100 diet. Diets supplemented with three levels of UFME stimulated lysozyme activity, phagocytic activity and white blood cells count of fish with the best effect in UFME100 (p < 0.05). Conclusively, dietary inclusion of 100 mg kg−1 UFME strongly improves health status, immune responses and antioxidant activity of Nile tilapia. [ABSTRACT FROM AUTHOR]

The present study investigated influence of Yucca schidigera extract (Ys E) on the growth performance, hepato‐renal function, antioxidative status and histopathological alterations in Nile tilapia (Oreochromis niloticus) exposed to hypoxia stress. 120 Nile tilapia fish (42.39 ± 1.25 g) were distributed into four equal groups, where group (a) kept as a control group, group (b) supplied with YsE (8 mg/L water every 2 days), group (c) exposed to hypoxia after 2 weeks from the start of the experiment and group (d) provided with YsE for 2 weeks and then exposed to hypoxia. The treatments were conducted for 30 days. The results showed that the level of DO was significantly decreased (2.2 ± 0.61) in groups of fish exposed to hypoxia when compared to other groups (p < 0.05). Notably, the pre‐supplementation with YsE to hypoxic stressed fish positively affected the WG, SGR, FCR and PER, relieved stress picture of leukogram, reduced the elevated hepatic marker enzymes: ALT, AST and LDH. Furthermore, hypoxic fish pre‐treated with YsE succeeded to decline the increased urea, glucose levels and the elevated serum amlyase and lipase enzyme activities. In addition to improving total proteins, albumin, total cholesterol, triglycerides, VLDL‐C and HDL‐C declined levels compared to hypoxic fish. Meanwhile hypoxia‐stressed fish exhibited significantly enhanced hepatic GPX, SOD and GSH and inhibited hepatic MDA content compared to fish supplied with YsE then exposed to hypoxia. Fish group pre‐supplemented with YsE then exposed to hypoxic stress condition was protected against the pathological changes of the liver, spleen, brain and gills tissues induced by hypoxic stress condition. These results suggest that YsE could exert a beneficial effect against hypoxia‐induced oxidative stress. [ABSTRACT FROM AUTHOR]

Microalgae are very important photosynthetic organisms in aquatic ecosystems and their use in biotechnology is increasing. One of the main uses is the addition of probiotic strains of lactic acid bacteria to algal biomass. In this research Chlorella vulgaris was used as a mechanical carrier of Bacillus casei and it was found that there is a strong relationship and the adhesion of the lactobacillus bacteria on the surface of the chlorella vulgaris as captured by EM. This indicates the ability to use the complex of algae and probiotic bacteria together as feed supplement which will enhance the function of these bacteria in the intestinal tract of aquatic animals. [ABSTRACT FROM AUTHOR]

In the present study sodium carbonate peroxyhydrate (2Na2CO3.3H2O2) which is considered as eligible algaecide and fungicide, was used as an alternative source of oxygen in fish ponds with concentration of 50 and 100 mg/L for 10 days. To approach our target hematological (RBCs, Hb, PCV, total and differential leukocytic count) together with several serum biochemical parameters as (glucose, total proteins, albumin, globulins, A/G, amino transferases (ALT, AST), urea and creatinine) were estimated. DNA fragmentation and a mild degree of DNA degradation as shown by DNA smear and a hallmark apoptosis were observed in samples from gills, brain and liver after 6 days of the experiment. Pathological changes started to appear first in the brain tissue then other organs (liver and kidney) were also affected after 6 days of the experiment with 100mg/L treated groups indicating the sensitivity of the brain and the direct effect of hypoxia on this organ. These results suggest the resistance of fish to oxygen depletion in case of using sodium carbonate peroxyhydrate (OXY-SOS) and the appearance of pathological changes after 6 days of use indicate its efficiency as alternative oxygen source. Thus, sodium carbonate peroxyhydrate (OXY-SOS) can be used as a stable oxygen releaser and as a suitable alternative to artificial aeration in fish farms for a period up to 6 days without adverse effect on treated fish. [ABSTRACT FROM AUTHOR]

Despite widespread use of bromuconazole as a pesticide for food crops and fruits, limited studies have been done to evaluate its toxic effects. Here, we evaluated the hepatotoxic effect of bromuconazole using classical toxicological (biochemical analysis and histopathological examination) and gene-based molecular methods. Male rats were treated either orally or topically with bromuconazole at doses equal to no observed adverse effect level (NOAEL) and 1/10 LD50 for 90 d. Bromuconazole increased activities of liver enzymes (ALT, AST, ALP, and ACP), and levels of bilirubin. It also induced hepatic oxidative stress as evidenced by significant decrease in the activities of superoxide dismutase (SOD), and significant increase in levels of malondialdehyde (MDA) in liver. In addition, bromuconazole caused an increase in liver weights and necrobiotic changes (vacuolation and hepatocellular hypertrophy). It also strongly induced the expression ofPXRand its downstream targetCYP3A1gene as well as the activity ofCYP3A1. However, it inhibited the expression ofCARand its downstream targetCYP2B1gene without significant changing inCYP2B1activity. Overall, the oral route showed higher hepatotoxic effect and molecular changes than the dermal route and all changes were dose dependent. This is the first investigation to report that bromuconazole-induced liver oxidative damage is accompanied by upregulation ofPXR/CYP3A1and downregulation ofCAR/CYP2B1. [ABSTRACT FROM AUTHOR]

In this study the differential expression of Myostatin gene was investigated in adult stage in Nile tilapia (Oreochromis niloticus) by realtime PCR. Myostatin gene was found to be expressed in various body tissues including: liver, intestine, gills, skin, spleen, kidneys, muscle, eyes and brain tissues. However, the highest expression level of Myostatin was found in brain tissue while the lowest expression level was in the spleen and eyes. These results support the early hypothesis suggested that Myostatin in fish have retained a different partition of the expression patterns compared with mammals. [ABSTRACT FROM AUTHOR]

Detection of species adulteration in meat products is important for consumer protection and food labeling law application. The threat and risk of food adulteration and mislabeling have become a large concern and challenge for the food control authorities and consumers. In this study 10 samples of Luncheon (beef) and 10 samples of Corned beef were collected from the local markets in Kafrelsheikh Governorate and examined for mislabeling detection by means of multiplex PCR. Results showed that 8 of the 10 samples Luncheon and all the 10 samples Corned beef were adulterated with goat's meat, while one sample of Luncheon was adulterated with equine meat, which were not in compliance with the label on the examined product. So, a strict national program by the concerned authority is required to protect consumers and prevent adulteration of food stuff. [ABSTRACT FROM AUTHOR]