Utilizing dietary probiotics can boost amberjack (Seriola dumerili) lysozyme activity, antioxidant capacity, and gut microbiota

In aquaculture, natural and eco-friendly resources are prioritized over synthetic inputs (e.g., antibiotics), and optimizing sustainable production methods is necessary. Probiotics have been well known for various potential functions in animal performance and health when supplemented as a single or mix of strain (s) in the diet. Consuming the right probiotic blend (synergistic types) is more advantageous than using each kind individually due to combining each species’ functions. The present trial aimed to examine the potential impacts of two probiotic mixtures on the performance and well-being of amberjack juveniles (5.63 ± 0.04 g; Number = 300) for a 60-day feed trial. Three experimental diets (43.5 ± 0.50% total protein and 12.55 ± 0.17% total lipid) were formulated with no probiotics supplement for the control (CD1) or with probiotics mixture supplement. Probiotic mixtures were supplemented at 2 g/kg diet for groups D2 [Bacillus amyloliquefaciens TOA5001 (BA) + Streptococcus faecalis T-110 (SF)] and D3 [Bacillus amyloliquefaciens, Streptococcus faecalis T-110, Lactobacillus plantarum TO-A, Bacillus mesentericus TO-A] respectively. The analysis revealed no difference in all means of growth parameters, feed utilization, survival rate, biometric indices, whole-body composition, and blood parameters between control and probiotic-supplemented diet groups. Liver lysozyme activity, superoxide dismutase, peroxidase activity, and biological antioxidant (BAP) were significantly improved in fish fed D2 compared to CD1 (P < 0.05). The higher (P < 0.05) content of intestinal lactic acid bacteria was noted in fish group fed diet D2, with an improved intestinal histological structure such as increased villi length, cryptal depth, and goblet cells compared to those provided with CD1 and D3 diets. In conclusion, incorporating a mix of probiotic bacteria [BA+SF] at a 2 g/kg diet has remarkable effects on intestinal health, immune responses, and oxidative status of amberjack, S. dumerili, suggesting a potential probiotic candidate for this species

Effect of Treating Eggs with Coenzyme Q10 (CoQ10) on Growth Variables, Histomorphometry, and Antioxidant Capacity in Red Tilapia (<i>Oreochromis aureus × Oreochromis mossambicus</i>) Larvae

Red tilapia eggs one day post fertilization (dpf) were exposed to coenzyme Q10 (CoQ10) at rates of 0, 5, and 10 mg/L for control, treatment 2 (C5), and treatment 3 (C10), respectively, without exchanging water and until the larval mouth-opening stage. Fertilized eggs of red tilapia exposed to different concentrations of CoQ10 were hatched at rates (p > 0.05) between 38 to 54.67%. The yolk-sac diameter at the 2nd day post hatching (dph), ranged from 1.85 to 1.87 mm in depth and 1.63 to 1.88 mm in width and was not altered by the CoQ10 treatments. Similarly, red tilapia survival (p > 0.05) ranged from 22.67 to 32%. On 6 dph, a slight percentage (2.08%) of survived fishes exposed to high CoQ10 dose (C10) exhibited larval deformation in the form of an axial curvature of the spine in the abdominal and caudal region. Larvae displayed a normal structure of the esophagus folds in all fish groups, and larvae in the C5 group displayed the longest folds and widest muscularis layer, followed by fishes in the C10 group and the control. Red tilapia fry on 30 dph treated with CoQ10 possessed higher antioxidant potentials in terms of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) compared to the control. In conclusion, treating Red tilapia fertile eggs with 5 mg/L CoQ10 improves the growth, gut structure, and antioxidant efficiency of the produced larvae

Synergistic interactions of zeolite, stocking density, and water exchange: A holistic approach to optimizing aquaculture performance of juvenile European seabass (Dicentrarchus labrax)

Effective water management is an essential component of sustainable fish farming practices, particularly in the context of global water scarcity. The accumulation of ammonium ions (NH4+) from fish metabolism necessitates frequent water changes, posing a challenge to the sustainability of fish farming operations. Zeolite materials have emerged as a promising solution, offering enhanced ammonium cation removal compared to conventional nitrifying bacteria. This innovative approach alleviates the pressure on water resources and promotes environmental sustainability in fish farming. Over 75 days, this study examined how zeolite, stocking density, and water exchange affected European seabass water quality and growth. 250 kg of seabass, 25.61 ± 2.39 g/fish. Three factors: zeolite levels (Z: 0, 10, and 15 ppt), density (D: 1, 2.5, and 5 kg/m3), and water exchange (W: 10, 25, and 50 %), using 81 hapas with 0.5 m3 vol each (triplicates for each treatment) fixed in concrete ponds, fish were randomly distributed among 81 experimental hapas in 27 ponds. This research illuminates the potential benefits of various therapies. Zeolite in seabass culture improved water quality. It reduced ammonia derivatives, improving water quality. Adjusting seabass stocking density to low or high improved water quality measures. This change kept dissolved oxygen levels within the target range, providing a good home for farmed fish. Zeolite supplements, reduced stocking density, and optimum water exchange improved European seabass growth, along with water quality improvements. These interventions improved feed consumption and growth rates. These approaches promoted fish growth and reduced stress by limiting the negative effects of high stocking density. The study also examined immune-related, hematobiochemical, and plasma biochemical characteristics after the interventions. Zeolite supplementation, to low stocking density, and water exchange improved these characteristics. They strengthened the European seabass' immune system and preserved healthy plasma and hematobiochemical parameters. In conclusion, optimizing European seabass culture with zeolite (15 ppt), stocking density (1 kg/m3), and water exchange (50 %) enhances water quality, growth performance, and physiological parameters. This contributes to improved aquaculture sustainability and efficiency. Further research is required to fully elucidate the molecular mechanisms of those factors that affect fish health and aquaculture practices

Effects of Different Aquafeed Sources on Growth Performance, Oxidative Capacity, and Fatty Acid Profile of Three Carps Reared in the Semi-Intensive Composite Culture System

The current experiment is designed to evaluate the effect of different aquafeeds (farm-made versus commercial) on growth, body composition, oxidative capacity, and fatty acid profile in the semi-intensive composite culture system. For this, 1,100 fingerlings/acre having initial body weight and length, Labeo rohita (61.34 g, 171 mm), Catla catla (71.45 g, 181 mm), and Cyprinus carpio (30.80 g, 91 mm) were randomly distributed to 16 ponds and randomly fed on eight different diets (n = 2 pond/diet) in a completely randomized research design. Aquafeed were farm-based diets (D1–D2) and commercial aquafeed (D3–D8). The farm-made diets contained various crude protein levels of maize gluten (24.9%) and rice polish (7.3%), whereas commercial diets were procured from commercial feed plants (AMG, Supreme, Aqua, Star Floating, Hi-Pro, and Punjab feed). The growth performance of carps (L. rohita and C. catla) was significantly improved (p0.05) across the treatments. These results also prove that the increase in the dietary protein level and lipid content can improve the fish’s body’s crude protein and fat levels. Feeding D3 improved the production performance, oxidative status, and fatty acid profile in composite major carps culture systems. Thus, based on growth, survival, and body composition, it is concluded that D3 and D4 may be recommended for a commercial culture of major carps. Dietary treatments had no significant impact (p>0.05) on water’s physical–chemical properties. Calcium content and alkalinity varied (p<0.05), with D5 showing the lowest calcium and the highest alkalinity

Growth variables, feed efficacy, survival rate, and antioxidant capacity of European seabass (Dicentrarchus labrax L.) larvae treated with Coenzyme Q10 or lipoic acid

A 30-day feeding trial was performed to assess the potential of the dietary supplementation of Coenzyme Q10 (CoQ10) and lipoic acid on acclimatized European seabass larvae with a preliminary weight and length of 2.7 mg and 12.42 mm (25 dph = days post-hatching). Seven experimental groups were fed on the basal micro-diet (56 % crude protein and 13 % crude lipid) without any supplement in the control group or with the addition of CoQ10 at levels of 5, 10, and 15 mg/kg or α-lipoic acid at levels of 50, 100, and 150 mg/kg, respectively. Larvae fed on a diet enriched with CoQ10 at levels of 5 and 10 mg/kg showed the highest values for final weight, weight gain, specific growth rate (SGR), the protein efficiency ratio (PER), and the lowest value for feed conversion ratio (FCR) as well as no morphological or histological abnormalities. Also, the group fed a diet supplemented with CoQ10 at 5 mg/kg gave the highest values for final length and survival. The survival rate ranged from 54.59 % to 79.82 % and the lowest rate was in the group fed a diet enhanced with lipoic acid at 150 mg/kg. Meanwhile, the lowest records for final weight, weight gain, protein efficiency ratio, and the presence of morphological and histological abnormalities were in groups fed on the control diet and with high levels of lipoic acids (100 and 150 mg/kg). Moreover, all lipoic acid groups showed deleterious signs in the histological structure of the intestine and liver. However, significantly lower values of catalase (CAT) and glutathione peroxidase (GPx) were found in the fish group fed on the basal diet, while the peak values were in groups fed on diets fortified with CoQ10 at 5 and 10 mg/kg. In addition, larvae fed CoQ10 at levels of 5 or 10 mg/kg performed better in terms of CAT and GPx activities than that fed lipoic acid at levels of 100 or 150 mg/kg. Furthermore, the control group displayed lower levels of insulin-like growth factor 1 (IGF-1), CAT, and GPx -related gene expressions while considerable upregulations of IGF-1 and GPx were noted in larvae groups fed on diets improved with CoQ10 at levels of 5 or 10 mg/kg and lipoic acid at 50 mg/kg compared to the others. Also, upregulations in CAT were found with CoQ10 at levels of 5 or 10 mg/kg compared to their counterparts in the other groups. In conclusion, dietary CoQ10 at 5 or 10 mg/kg improves the performance and well-being of European seabass

Assessing chamomile and marjoram meals as feed additives on growth indices and haematological parameters of Nile tilapia (Oreochromis niloticus) reared under biofloc system

First report on using chamomile (Matricaria chamomilla) flower meal [CFM] and marjoram (Origanum majorana) leaves meal [MLM] as dietary supplements in low-protein fish diets on Nile tilapia (Oreochromis niloticus) reared in a bio-floc system. The experiment consisted of 6 groups in triplicates, where the first (T1) and second (T2) groups were fed diets containing 25 and 20% protein, respectively, without any additives. In contrast, the rest of the groups were fed a 20% protein diet, adding CFM at rates of 1% (T3) and 2% (T4) or MLM at rates of 1% (T5) and 2% (T6). The fish were initially weighed 18.44 g ± 0.38 (S.E.) and randomly stocked in 18 experimental tanks at six fingerlings in a water volume of 40 litres (150 fish/m3). Molasses was used as a carbon source with a carbon-to-nitrogen ratio of 16:1 in the treatments fed 20% protein; 12:1 in the treatments provided 25% protein. Feeding was done twice daily, six days a week, at a rate of 3% of body weight for 42 days. Water quality was within the desirable tilapia growth and health limit regarding temperature (23.20 - 24.70 °C), pH (8.43 - 8.65), dissolved oxygen (5.5 - 6.1 mg/L), and NH3 (0.03–0.051 mg/L). Fish fed on a 20% CP diet containing 1% CFM had the highest values in all growth indicators, followed by 2% CFM and 1% MLM then T1 and T2 groups. Blood analysis showed variation (P ≤ 0.05) among groups, and T3 had the highest levels of hemoglobin (Hb), hematocrit (Hct), and red blood cells (RBCs) followed by T5 then T4, T2, while T6 and T1 were the least. In conclusion, using chamomile or marjoram as a feed supplement maximizes the benefits of using the bio-floc system, especially in a lack of water resources and poor protein feeds. Nile tilapia growth and hematological parameters were the best with a 1% chamomile (M. chamomilla) supplement under a biofloc system

Effects of replacing fishmeal with fermented and non-fermented rapeseed meal on the growth, immune and antioxidant responses of red sea bream (Pagrus major)

The effect of rapeseed meal (RM) and Aspergillus oryzae fermented rapeseed meal (RM-Koji) on red sea bream (Pagrus major) was examined. Three groups of fish (initial weight, 4.5 ± 0.02 g) were fed a basal diet (RM0) and two test diets where half of fishmeal was replaced by RM (RM50) and RM-Koji (FRM50) for 56 days. The obtained results showed that fish fed RM0 and FRM50 exerted significantly higher growth performance, feed utilization and haemoglobin level but lower triglyceride and cholesterol than RM50 group (p < 0.05). Interestingly, except of antiprotease activity, all the immune parameters including lysozyme, respiratory burst (NBT) and bactericidal activities were significantly increased in fish fed RM0 and FRM50 diets compared to RM50 diet (p < 0.05). In addition, malondialdehyde and reactive oxygen metabolites were significantly reduced in RM0 and FRM50 groups over RM50 group (p < 0.05). The present results suggest that fermented RM induced better growth performance and immune responses than feeding red sea bream with non-fermented RM and both RM and RM-Koji improved the antioxidative status of fish, making RM-Koji an interesting candidate as a functional feed for aquatic animals