Isatis phytogenic relieved atrazine induced growth retardation, hepato-renal dysfunction, and oxidative stress in Nile tilapia.

The influence of herbicides causes health and economic loss, which requires innovative solutions to sustain the aquaculture industry. In this regard, dietary isatis is included in Nile tilapia diets to relieve atrazine (ATZ)-induced growth retardation, hepato-renal dysfunction, and oxidative stress. The first and second groups offered the control diet (control), while the third and fourth groups offered the isatis supplemented diet (1%). Meantime, half of the water was replaced and mixed with ATZ (1.39 mg/L) in the second and fourth groups for 30 days. The group of fish delivered isatis had significantly enhanced FBW, WG, and SGR, while fish intoxicated with ATZ had meaningfully impaired growth behavior (p < 0.05). Further, the FCR was improved by isatis, and ATZ resulted in the worst FCR among the groups. Interestingly fish fed isatis and exposed with ATZ (88.89%) had a higher survival rate than fish exposed with ATZ without isatis feeding, and both are lower than the control (97.78%) (p < 0.05). The histological structure in the isatis-treated groups showed distinguished enhancement and branching of the intestinal villi. The intestine of ATZ-treated fish revealed damage and inflammatory cell infiltration in the intestinal mucosa with separation of lining epithelium. Generally, fish fed isatis and intoxicated with ATZ had lower uric acid, urea, creatinine, ALT, and AST and higher total protein, globulin, and albumin than fish exposed with ATZ without feeding with isatis (p < 0.05). Markedly, fish-fed isatis had the highest SOD, CAT, GPx, and the lowest MDA level compared to the other groups (p < 0.05). Meanwhile, fish exposed with ATZ had the worst SOD, CAT, GPx, and the highest MDA level compared to the other groups (p < 0.05). In summary, dietary isatis relieved ATZ induced growth retardation, hepato-renal dysfunction, and oxidative stress in Nile tilapia.

Role of Fucoidan on the Growth Behavior and Blood Metabolites and Toxic Effects of Atrazine in Nile Tilapia Oreochromis niloticus (Linnaeus, 1758).

Waterborne herbicides are stressful agents that threaten the productivity and safety of finfish species. In this study, the toxicity impacts of atrazine (ATZ) and the protective role of fucoidan were investigated on the health performance of Nile tilapia. For 40 days, the total number of 180 Nile tilapia was assigned in four groups (triplicates, 15 fish/replicate), where the first (control) and third groups were offered the control diet, while the second and fourth groups were offered a fucoidan (FCN). Further, in the third and fourth groups, the water was mixed with atrazine (ATZ) at 1.39 mg/L daily. The growth rate, FCR, and survival rate were markedly enhanced by fucoidan but severely declined by ATZ exposure (p < 0.05). The morphological structure of the intestine in the control fish revealed normal structure, while fucoidan-treated groups showed eminent enhancement and branching of the intestinal villi. The intestine of ATZ-treated fish revealed deterioration and the intestinal mucosa, inflammatory cell infiltration, and separation of lining epithelium. The highest Hb, PCV, RBCs, WBCs, total protein, and albumin were observed in Nile tilapia fed fucoidan, but the worst values were seen in ATZ-intoxicated fish (p < 0.05). The liver-related enzymes (ALT and AST) and kidney function (urea and creatinine) showed impaired values by ATZ toxicity and were regulated by dietary fucoidan. Meanwhile, fish fed fucoidan and exposed to ATZ had lower total cholesterol and triglyceride values than fish exposed to ATZ without fucoidan feeding (p < 0.05). The SOD, CAT, GPx, cortisol, and glucose levels were increased in ATZ-exposed fish and reduced by fucoidan (p < 0.05). However, the level of malondialdehyde (MDA) was reduced in fucoidan-fed fish and increased in ATZ-exposed fish (p < 0.05). Altogether, dietary fucoidan is required in fish diets to alleviate the impacts of ATZ-induced toxicity.

Nutritional value and bioaccumulation of heavy metals in muscle tissues of five commercially important marine fish species from the Red Sea.

The study evaluated the nutritional quality and investigated the heavy metals concentration in muscle tissues of five commercially important marine fish species, including brownspotted grouper (Epinephelus chlorostigma), squaretail coralgrouper (Plectropomus areolatus), black pomfret (Parastromateus niger), goldbanded jobfish (Pristipomoides multidens), and blueskin seabream (Polysteganus coeruleopunctatus) from the Red Sea, Jeddah Coast, Saudi Arabia. Significant differences (p < 0.05) were observed in the proximate chemical composition of fish muscles in these species. The highest protein content (17.66 ± 0.58%) was achieved in blueskin seabream while the lowest (15.28 ± 0.46%) was observed in brownspotted grouper. The highest lipid content (2.97 ± 0.45%) was recorded in squaretail coralgrouper while the lowest (1.52 ± 0.26%) was observed in blueskin seabream. Heavy metal concentrations varied significantly within and between fish species under study (p < 0.05). Significant differences in the concentration of heavy metals among fish species were recorded. Results revealed that the bioaccumulation of Cr, Fe, Ni, and Cd in muscles of fish species under study was higher than the standard concentration, but that of Mn, Cu, and Pb were less than the standard concentration recommended in the EU, FAO, and WHO guidelines. In conclusion, these fish species represent a high-quality food source but is unsafe due to the level of certain minerals in their tissues. Results also indicated that the Red Sea environment is contaminated with heavy metals, which was reflected in the tissues of fishes used in this study.

Demographic structure and stock status of Lethrinus lentjan in Saudi coastal waters of the Red Sea.

Fishes of the family Lethrinidae form a considerable portion of the catch from both the Red Sea and the Arabian Gulf in Saudi Arabia, and the species Lethrinus lentjan (Lacepède, 1802) is one of the most important among these fishes. This study was conducted to evaluate the demographic structure coefficients, survival rate, and stock status of L. lentjan from the Red Sea coast of Saudi Arabia. A total of 593 samples were collected on a monthly basis for a period of one year from the landing site for fishing boats operating in Red Sea waters off Jeddah. The results indicated that 88.87% of the specimens were female; the maximum total length recorded was 43.5 cm with the most frequent length (14.67%) being 23-23.9 cm. The maximum age recorded for both males and females was 6 year-plus, and the 1 year-plus age category represented the majority of the samples (57.67%). The total mortality coefficient, natural mortality coefficient, and fishing mortality coefficient were 1.538, 0.315, and 1.223, respectively; all mortality coefficients in the female fishes were higher than those in the male fishes. The survival rate of males was higher (0.617) than that of females (0.214). The results of the present study indicate that L. lentjan is subjected to overfishing and a new management strategy is necessary to improve the stock status of this fish species.

Dye degradation, antimicrobial and larvicidal activity of silver nanoparticles biosynthesized from Cleistanthus collinus.

The present study aimed in green synthesis and characterization of silver nanoparticles (AgNPs) using the leaves of Cleistanthus collinus. The NPs showed various absorption peaks between 3402 cm-1 and 1063 cm-1. FTIR spectrum revealed the presence of OH group, alkene, aromatic hydrocarbon, aliphatic fluro compound and aliphatic chloro compounds. Scanning electron microscopic analysis revealed the particle size ranged from 30 to 50 nm. The biosynthesized NPs have potent activity against Shigella dysentriae, Staphylococcus aureus and Bacillus subtilis and the zone of inhibition was 21 ± 1, 20 ± 2, 16 ± 2 mm, respectively. Toxicity of the synthesized NPs was tested on green gram (Vigna radiata) seed at various concentrations (20-100%) and germination was induced by NPs treated seeds. Shoot length and root length was higher in NPs treated plant than control plant (p < 0.01). Elevated level of catalase (CAT) and superoxide dismutase (SOD) and about 13% CAT and 7% SOD activity registered than control. Superoxide dismutase activity of root and shoot varied based on the dosage of AgNPs (p < 0.01). Also, the NPs (1%) showed significant larvicidal activity on Aedes aegypti and 100% mortality was achieved after 24 h treatment. The green synthesized NPs reduced methylene blue and 4-nitrophenol significantly (p < 0.01). The colouration of methylene blue and 4-nitrophenol were considerably reduced after 60 min showed the potential of dye degrading ability.

Bioaccumulation of lead nitrate in tissues and its effects on hematological and biochemical parameters of Clarias gariepinus.

Clarias gariepinus, weighing 119.18 ± 5.21 g, were exposed to 0%, 20%, 40%, and 60% of the LC50 lead nitrate, Pb(NO3)2, which represents the following treatments 0 (control), 16, 32, and 48 mg/l, respectively, for a period of 10 and 20 days. The results showed that the bioaccumulation of Pb(NO3)2 in gills were significantly increased (p < 0.05) after 10 days having 0.17 ± 0.07, 5.05 ± 1.04, 6.01 ± 0.82, and 9.61 ± 1.76 mg/100 g wet weight, respectively, for the treatments. However, after 20 days these values increased ((0.17 ± 0.07, 4.34 ± 1.27, 10.83 ± 0.97, and 19.18 ± 2.40 mg/100 g) for 0%, 20%, 40%, and 60% of LC50 Pb(NO3)2 respectively. There was an increase with each increasing concentration level of Pb(NO3)2 as compared with that of the control group. The accumulation of Pb(NO3)2 in the liver, showed a significant increase (p < 0.05) with the increasing period of exposed and Pb concentration with LC50 values ranging between 3.32 ± 0.91 and 4.42 ± 0.78 after 10 days as compared with that of the control group 0.08 ± 0.02 mg/100 g wet weight. Although white muscles and skin displayed lower values of bioaccumulation than gills and liver after 10 days, after 20 days the results were slightly more increased in the white muscles than in the skin. However, the observed pattern of increase was the same compared to that of the control group. Therefore, hematological parameters, such as red blood cells (RBCs), hemoglobin (Hb), and hematocrit (Hct) showed significant (p < 0.05) concentration-dependent decreases in fish exposed to Pb(NO3)2 during both periods. However, the values of white blood cells (WBCs) showed a significant reduction when levels of Pb concentration increased. Hepatic enzyme activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) displayed a significant increase with increasing concentrations and exposure time.

Effect of dietary fish meal replacement by red algae, Gracilaria arcuata, on growth performance and body composition of Nile tilapia Oreochromis niloticus.

A 12-week long feeding experiment was initiated to evaluate the effect of dietary supplementation of red algae, Gracilaria arcuata, on the growth performance, feed utilization and body composition of Nile tilapia Oreochromis niloticus (Linnaeus, 1758). The fish were fed with an algae-free control diet (C) and three experimental diets which replaced conventional fish meal with varying levels of dried G. arcuata (20%, 40% and 60%, represented as G20, G40 and G60, respectively). The growth parameters of final weight (FW), weight gain (WG), percentage of weight gain (WG%), daily growth rate (DGR) and specific growth rate (SGR) were significantly reduced (P < 0.05) at all levels of algae incorporation compared to the control diet. Moreover, the negative impact of Gracilaria meal on the growth performance of Nile tilapia increased as the proportion of algae in the diet increased, with fish on diet G20 exhibiting a significantly higher growth performance than the fish on either of the G40 and G60 diets. On the other hand, the feed utilization parameters feed conversion ratio (FCR) and protein efficiency ratio (PER) did not show significant differences between the fish in the control group and those on diet G20, although poorer FCR and PER outcomes were achieved in the case of fish on diet G60. The content of moisture, protein and ash in muscle and carcass increased as the proportion of Gracilaria meal in the diets increased, but the reverse was true for lipid level. These results indicate that incorporation of less than 20% red algae, Gracilaria arcuata, could be feasible in the diet of Nile tilapia and further studies are recommended to optimize the level of algae to improve growth performance.

Potential use of green macroalgae Ulva lactuca as a feed supplement in diets on growth performance, feed utilization and body composition of the African catfish, Clarias gariepinus.

This study aimed to evaluate the effects of diet containing the green macroalgae, Ulva lactuca, on the growth performance, feed utilization and body composition of African catfish Clarias gariepinus. Four experimental diets were formulated: D1 as a control group and D2, D3 and D4 which included 10%, 20% and 30% U. lactuca meal, respectively. 180 African catfish, weighing 9.59 ± 0.43 g, and with an average length of 11.26 ± 0.21, (mean ± SE) were divided into four groups corresponding to the different feeding regimes. The final body weight of the fish showed insignificant differences (P > 0.05) between the control and fish fed D2, whereas, there was a significant difference (P < 0.05) between these two diets compared with D3 and D4, with weights of 70.52, 60.92, 40.57 and 35.66 g recorded for D1, D2, D3 and D4, respectively. In the same trend significant differences were also evident in weight gain, specific growth rate and feed utilization. Fish fed with a diet containing 20% or 30% U. lactuca meal had poorer growth performance and feed utilization. Protein productive value, protein efficiency ratio, daily dry feed intake and total feed intake were also significantly lower in fish fed with D3 and D4 than in the control D1 and D2. Overall, the results of the experiment revealed that African catfish fed a diet with U. lactuca included at 20% and 30% levels showed poorer growth and feed utilization than the control group and fish fed diets containing 10% of U. lactuca.

Evaluation of red seaweed Gracilaria arcuata as dietary ingredient in African catfish, Clarias gariepinus.

The aim of this study was to evaluate the use of dried marine seaweed, Gracilaria arcuata for the first time as dietary ingredient in partial substitution of fishmeal on the growth performance, feed utilization and body composition of African catfish, Clarias gariepinus. Four experimental diets were formulated: D1 as a control group; D2; D3 and D4 which included 10%, 20% and 30% G. arcuata meal respectively. One hundred and eighty African catfish weighing 9.62 ± 0.42 g, (mean ± SE) was divided into four groups corresponding to the different feeding regimes. The final body weight of the fishes showed significant differences (P < 0.05) between the control (D1); D2 and other treated groups D3 and D4, with weights of 66.98, 59.60, 47.34 and 30.73 g recorded for D1, D2, D3 and D4, respectively. Significant differences (P < 0.05) were also evident in weight gain, specific growth rate, and feed utilization between treatment and control groups. However, no significant differences (P > 0.05) were observed between the control group and fishes fed D2 for all previous parameters. Protein productive value, protein efficiency ratio, daily dry feed intake and total feed intake were also significantly lower in fish fed with a diet containing G. arcuata than in the control group and D2 which contains 10% of G. arcuata. Overall, the results of the experiment revealed that African catfish fed a diet with G. arcuata included in 20% and 30% levels showed poorer growth and feed utilization than the control group and D2. However, the study recommended that C. gariepinus can accept this ingredient up to 10% in their diets. More defined experiments therefore seem to be necessary in order to determine the maximum level of this marine seaweed in diets with amino acid supplementation for African catfish.

Haematological and biochemical parameters and tissue accumulations of cadmium in Oreochromis niloticus exposed to various concentrations of cadmium chloride.

Oreochromis niloticus, weighing 36.45 ± 1.12 g were exposed to 10%, 20% and 30% of the LC50 of CdCl2 which represents treatments (T1)1.68, (T2)3.36 and (T3)5.03 mg/l, respectively, for a period of 10, 20 and 30 days. It was found that, compared to a control group reading of 0.19 ± 0.03 µg/g dry weight, accumulation of Cd in the gills was significantly (p < 0.05) increased in samples ranging between 7.64 ± 0.86 and 61.73 ± 0.82 µg/g dry weight from T1 at 10 days to T3 at 30 days. The accumulation of Cd in the liver, meanwhile, was also observed to significantly increase (p < 0.05) with increasing time and concentrations with results ranging between 3.21 ± 0.12 and 181.61 ± 1.32 compared to the control group results of 0.29 ± 0.04 µg/g dry weight. Although muscles exhibited lower levels of accumulation than the gills and liver they still showed the same pattern of increase compared to the control group, with a significant difference ranging between 0.32 ± 0.02 and 2.16 ± 0.08 compared to the control group results of 0.03 ± 0.001 µg/g dry weight. Also, haematological parameters such as red blood cells (RBCs), haemoglobin (Hb) and haematocrit (Hct) were reduced in fish exposed to Cd at all periods, with significant differences (p < 0.05). Plasma glucose concentration showed a significant increase. Total protein levels of fish showed a significant reduction (p > 0.05) for all exposed treatments. Also, the total lipid level increased significantly as fish were exposed to increasing cadmium concentrations, compared to control fish. Finally, the activities of aspartate aminotransferase (AST IU/l) and alanine aminotransferase (ALT IU/l) showed a significant increase (p < 0.05) with increasing time and concentrations.

Seasonal variations in the body composition and bioaccumulation of heavy metals in Nile tilapia collected from drainage canals in Al-Ahsa, Saudi Arabia.

The body composition of Nile tilapia (Oreochromis niloticus) collected from drainage canals in Al-Ahsa, Saudi Arabia and the concentration of four heavy metals; zinc (Zn), cadmium (Cd), cobalt (Co) and lead (Pb) in both fish muscles and the water collected from this environment were assessed across the four seasons. The body composition was found to change with the seasons, with the best body composition being recorded in autumn and winter, where higher levels of protein (17.24, 17.65%), and fat (0.58, 0.71%) and lower water content (80.15, 79.86%) respectively were noted. The concentration of heavy metals in both fish muscles and the water body also varied significantly with the seasons. In the fish muscles, the highest content of Zn (0.409 mg/kg dry weight) and Cd (4.140 mg/kg dry weight) was recorded in winter, however, the highest concentration of Co (0.318 mg/kg dry weight) and Pb (1.96 mg/kg dry weight) was observed in spring and summer respectively. On the other hand, the water samples collected in autumn showed the maximum concentration of Cd (1.385 mg/L), Co (0.762 mg/L) and Pb (0.18 mg/L) however, the maximum concentration of Zn (0.0041 mg/L) was recorded in winter. With the exception of Cd, the accumulation of the studied heavy metals in fish muscles was within the safe limits for seafood recommended by various organizations.