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Simple Summary: Pumpkin by-products such as seeds, and pomace can be a source of nutrients for aquatic organisms. In a study evaluating the inclusion of Japanese pumpkin seeds and pomace in the diet of the Pacific white shrimp Penaeus vannamei, we found that the seeds had a negative effect on shrimp performance and a pro-oxidative effect on muscle, whereas pumpkin pomace improved the feed conversion ratio and antioxidant activity of feeds and muscle and resulted in shrimp becoming more orange, both when fresh and after cooking. We do not recommend the inclusion of pumpkin seeds in the diets of P. vannamei, and we suggest further studies evaluating higher levels of inclusion of pumpkin pomace. A 60-day feeding trial was conducted to evaluate the effects of including pumpkin seeds and pomace in the diets of Pacific white shrimp Penaeus vannamei, and the effects of these supplements on growth performance, body composition, and total polyphenol, flavonoid and carotenoid contents, as well as on total antioxidant activity, and body color parameters. Five diets were evaluated: pumpkin seeds (PS) at 50 and 100 g·kg−1, pumpkin pomace (PP) at 50 and 100 g·kg−1, and a control treatment. Pacific white shrimp (P. vannamei) juveniles (0.60 ± 0.01 g) were stocked in 15 tanks (310 L), containing 30 shrimps per tank, and the treatments were randomly distributed in triplicate. At the end of the experiment, shrimps were euthanized, weighed, and dissected for further analyses. The inclusion of PS in the diets impaired growth performance, reduced the total flavonoid content and had a pro-oxidative effect on muscle. The inclusion of PP in the diets did not affect growth performance, improved the feed conversion ratio, increased the total flavonoid content in the diets and hepatopancreas, and improved the antioxidant activity of the feeds and shrimp muscle. The total carotenoid content of the feeds increased with the inclusion of PS or PP in the diets; however, the total carotenoid content of shrimp increased only in those fed PP diets. Shrimp fed with PS diets showed a yellowish color and higher saturation when fresh and a reddish color and yellow hue angle after cooking. Shrimp fed PP diets turned reddish and yellowish, both when fresh and after cooking. The inclusion of PS in P. vannamei diets is not recommended; however, PP can be included at 100 g·kg−1 without affecting the growth parameters. Further studies evaluating the inclusion of higher PP levels in shrimp diets are recommended. [ABSTRACT FROM AUTHOR]

Phosphorus is an essential mineral present in the vegetable matter in the form of phytate, which is considered an antinutritional factor. Phytate can be degraded by phytases, which have been used in commercial feeds. However, these enzymes undergo costly isolation and purification processes. In the present study, a genetically modified (GM) Bacillus subtilis strain that expresses a fungal phytase was used as a feed additive. The GM probiotic was added to the commercial feed of shrimp Litopenaeus vannamei and its effects on zootechnical performance, proximate composition of muscle, lipid concentration in hepatopancreas, and expression of genes related to digestion, amino acid metabolism, and antioxidant defenses were analyzed. Although the genetically modified probiotic had no impact on growth parameters, there was a 39% increase in phosphorus content in muscle. In addition, genes related to digestion were downregulated in shrimp hepatopancreas, as well as an increase in lipids in this tissue. These results demonstrate that the GM probiotic increased the efficiency of the use of plant-derived phosphorus, which may imply a decrease in the addition of this element in the diets, as well as minimizing the impact of shrimp farms on the eutrophication of adjacent ecosystems. [ABSTRACT FROM AUTHOR]

Several methods are used to recover compounds from these residues. Among them, ultrasound extraction has gained prominence due to its cellular disruption power. This work aimed to verify the action of ultrasound in increasing the yield of protein hydrolysate extraction from Pacific white shrimp (Litopenaeus vannamei) by-products. Proximal composition, hydrolysis degree, total content of carotenoids, and antioxidant activity (DPPH, ABTS, and reducing power) of the obtained hydrolysate was determined. The study found that the use of ultrasound concentrated more carotenoids, containing high antioxidant activity, increased the degree of hydrolysis, and accelerated the hydrolytic reaction rate. [ABSTRACT FROM AUTHOR]

Innovation in aquaculture nutrition is linked to the use of new compounds, in order to achieve a more sustainable production. The grapefruit industry is one of the biggest in the fruit sector due to the enormous wine and juice production. As a consequence, tons of grape bagasse (GB) turn into waste every year, a product rich in antioxidants such as polyphenols (PPS). Shrimp Litopenaeus vannamei is generally cultured under stressful conditions such as crowding, which can increase the production of reactive oxygen species (ROS) and could benefit from feed with functional properties. Five isoproteic and isolipidic diets were formulated: GB0, GB2.5, GB5, GB10 and GB15% of GB inclusion; those diets were tested in triplicate. Shrimp juveniles (0.35 ± 0.01 g) were stocked at a density of 150 shrimp m−3, and fed for 45 days. At the end of the experimental period, hepatopancreas and muscle samples of shrimp were collected for the determination of the antioxidant capacity against peroxyl radicals (ACAP), thiobarbituric acid‐reactive substances (TBARS) and PPS content. The results indicate that it is possible to add up to 2.5% of GB inclusion without affecting growth and feed conversion rate significantly. Also, the shrimps muscle of the GB15 treatment presented the highest PPS concentration and the lowest lipid peroxidation. In conclusion, it is possible to include GB in shrimp diets in small amounts, despite not obtaining significant antioxidant benefits. [ABSTRACT FROM AUTHOR]

This study investigated the effects of the inclusion of Mauritia flexuosa fruit pulp in the diet on the growth performance, economic benefit, muscle composition, total contents of carotenoids and flavonoids, chromaticity parameters, total antioxidant capacity, and lipid peroxidation in the hepatopancreas and muscle of the juvenile shrimp Litopenaeus vannamei (weighing 1.26 ± 0.023 g). Five diets (37% protein, 10% lipid) consisting of 0 (control), 1.25%, 2.50%, 5.00% and 10.00% (w/w) M. flexuosa fruit pulp were formulated and provided to the shrimps (n = 50 per tank, treatments in triplicate) for 31 days. Results showed that there were no significant differences between the treatments in terms of the growth capacity, chromaticity parameters, muscle composition and total flavonoid content of shrimps (p >.05). However, the carotenoid content in the muscle and hepatopancreas of the shrimps was significantly increased due to the dietary carotenoids present in M. flexuosa fruit pulp (p <.05). This increase in the carotenoid content directly favoured the increase in the antioxidant capacity in the hepatopancreas and muscle of the shrimps (R2 = 0.99 and R2 = 0.97 respectively; p <.05). There was also a direct relationship between the carotenoid content and the decrease in lipid peroxidation in the hepatopancreas (R2 = 0.90; p <.05). The feed cost kg−1 in terms of weight gain and protein production decreased with the inclusion of high levels of M. flexuosa fruit pulp, reaching 8.11% and 18.76% of cost reduction, respectively, with the addition of 5.00% of M. flexuosa fruit pulp. Therefore, the inclusion of M. flexuosa fruit pulp in the diets of shrimp can increase the carotenoid content and the antioxidant capacity in the hepatopancreas and muscle, reduce lipid peroxidation in the hepatopancreas, and probably provide economic benefits for the rearing of juvenile shrimps. [ABSTRACT FROM AUTHOR]

This study investigated the effects of the use of the inclusion of açaí on the diet of shrimp Litopenaeus vannamei on antioxidant and histopathological responses after exposure to ammonia. The shrimps were fed two experimental diets: control and with 10% of açaí inclusion (W/W), for 35 days. Afterwards, the organisms were exposed at four concentrations of ammonia (0.01‐control; 0.26; 0.48 and 0.91 mg NH3‐N L−1) for 96 hr. The total antioxidant capacity (ACAP) of the gills decreased significantly in both diets when exposed to ammonia, whereas in the muscle, the açaí promoted an increase in ACAP. Concomitantly, lipid peroxidation levels increased in the gills and decreased in muscle. After exposure to ammonia, glutathione‐S‐transferase activity increased in hepatopancreas in shrimps fed with açaí facilitating the detoxification of lipid peroxidation by‐products, and the concentration of protein sulfhydryl groups decreased in the gills and muscle of the shrimp of the control diet, evidencing protein damage, an unobserved response in shrimps that received the açaí diet. Histopathological changes decreased in açaí‐fed shrimps about the control diet after exposure to ammonia. It is concluded that açaí mitigated ammonia‐induced histopathological changes, improved the antioxidant defence system (gills and muscle) and attenuated the lipid damage in the muscle. [ABSTRACT FROM AUTHOR]

Abstract: Nutritional values of microbial floc meal and soy protein concentrate were evaluated as alternative protein sources to fishmeal in diets for Litopenaeus vannamei juveniles. A feeding trial was conducted during 28days to investigate the effects of partial and total replacement of fishmeal with microbial floc meal and soy protein concentrate on feed intake and growth of L. vannamei. Five diets were formulated to contain 38% crude protein and 17kJ/g gross energy. Microbial floc meal was obtained from super-intensive shrimp farm effluent. A control diet (with fishmeal as the main protein source) was compared to four diets containing microbial floc meal and soy protein concentrate at 25%, 50%, 75% and 100% replacement levels and a commercial diet. This feeding trial was conducted in a recirculating aquaculture system, utilizing shrimps weighing 2.48±0.29g. The weight gain, final weight, feed conversion ratio, specific growth rate, protein efficiency ratio and survival were not significantly different among treatments, suggesting that fishmeal can be completely replaced with soy protein concentrate and microbial floc meal without adverse effects on L. vannamei performance. These results suggest that a mixture of soy protein concentrate and microbial floc meal can be utilised as a substitute for fishmeal in diets for L. vannamei juveniles. [Copyright &y& Elsevier]

In the field of shrimp aquaculture, the utilization of probiotics represents a promising avenue, due to the well-documented benefits conferred by these microorganisms. In the current study, a Bacillus subtilis strain, referred to as strain E, was isolated from the gastrointestinal tract of the shrimp Litopenaeus vannamei and subsequently identified via molecular methods and phylogeny. The probiotic potential of strain E was characterized, and its application as a feed shrimp additive was evaluated in a 45-day experiment. Several parameters were assessed, including zootechnical performance, muscle tissue proximate composition, hepatopancreas lipid concentration, and the expression of genes associated with digestion, amino acid metabolism, and antioxidant defense mechanisms in various shrimp tissues. Although no significant impact on zootechnical performance was observed, supplementation with strain E led to an increase in lipid concentration within both muscle and hepatopancreas tissues. Furthermore, a marked decrease in the expression of genes linked to digestion and amino acid metabolism was noted. These findings suggest that the addition of the B. subtilis strain E to shrimp feed may enhance nutrient absorption and modulate the expression of genes related to digestion and amino acid metabolism. [Display omitted] • B. subtilis strain E was isolated from the gastrointestinal tract of L. vannamei ; • Strain E showed probiotic potential and was used as a supplement in shrimp feed; • Shrimps fed with strain E had increased lipid content in muscle and hepatopancreas; • Strain E diet downregulates genes related to digestion and amino acid metabolism. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of dietary inclusion of lyophilized açaí Euterpe oleracea (LEO) on redox status of shrimp Litopenaeus vannamei (initial weight 1.5 ± 0.39 g) upon exposure to cyanotoxin nodularin (NOD) in bioflocs system. Three hundred juvenile shrimps were randomly divided into two groups and fed twice a day with two diets: one containing 0.00 (control diet) and the other 10.0% LEO (w/w) for 30-days. After the feeding period, both shrimp groups were submitted to three treatments (14 L; 7 shrimp/tank) with different concentrations of cyanotoxin NOD (0.00; 0.25; and 1.00 μg/L) dissolved in water with 96 h of exposure. Then, the shrimps were sampled (n = 15/treatment) for the determination of reduced glutathione (GSH), the activity of glutathione-S-transferase (GST), sulfhydryl groups associated to proteins (P-SH), and lipid peroxidation (TBARS) in the hepatopancreas, gills and muscle. The NOD accumulation was measured in the muscle. The results revealed that dietary LEO significantly increased GSH levels in the hepatopancreas and gills of the shrimps exposed to NOD. Toxin exposure did not modify GST activity in all organs. Muscle TBARS levels were lower in the shrimp fed with the LEO diet and exposed to NOD. The NOD toxin did not accumulate in the muscle but notably was detected in the control groups fed or not with dietary LEO. Açaí was able to induce the antioxidant system of L. vannamei , as well as lowered the oxidative damage in shrimps exposed to NOD, suggesting its use as a chemoprotectant against cyanotoxins. • It was evaluated the use of açaí Euterpe oleracea as a chemoprotectant. • Shrimps L. vannamei were exposed to cyanotoxin nodularin (NOD). • Açaí increased glutathione levels in shrimps exposed to NOD. • Açaí lowered the oxidative damage in shrimps exposed to NOD. [ABSTRACT FROM AUTHOR]

Abstract: The use of fishmeal (FM) and fish oil in aquafeeds is a major challenge in the development of aquaculture. The discovery of alternative ingredients for aquaculture feedstuffs will allow for the sustainable growth of this activity. The cyanobacteria Arthrospira (Spirulina platensis) contains high quality protein and also immune-stimulatory properties that have been tested in mammals, fish and crustaceans. The purpose of this work was to evaluate the growth and immunological parameters of the white shrimp Litopenaeus vannamei when it was fed experimental isonitrogenous diets (~35% protein), containing 0%, 25%, 50%, 75% and 100% cyanobacteria A. platensis replacing fishmeal for 50days. At the end of the experiment, there were no significant differences (p <0.05) in growth performance among the shrimp fed diets with up to 75% fishmeal replacement. The immunological parameters differed significantly in the percentage of hyaline and granular hemocytes in the shrimp fed the diets with at least 25% fishmeal replacement. The apoptotic index also showed highly significant differences, but only in those shrimp fed a diet consisting of 100% fishmeal replacement. The results showed that up to 75% of fishmeal could be replaced by A. platensis without affecting survival or creating a growth depression. Moreover, the smaller substitution level (25%) promoted an enhancement of the tested immunological parameters. [Copyright &y& Elsevier]

This study evaluated the effects of dietary supplementation with different concentrations of chitosan from shrimp tailings on the antioxidant and immune systems of juvenile Litopenaeus vannamei cultivated in a biofloc system (BFT) and subjected to abrupt salinity reduction. The experiment was performed with juvenile shrimp fed diets supplemented with four levels of chitosan: C0 (0 g kg−1 diet – control), C1 (1 g kg−1 diet), C3 (3 g kg−1 diet), and C5 (5 g kg−1 diet). After 35 days, the shrimp were exposed to an acute reduction in salinity from 30 to 5 for 24 h, and the hemolymph, gills, and hepatopancreas were collected. No significant differences were found in the growth performance and survival among treatments. In the gills, acute salinity reduction increased the activity of catalase (CAT), although this effect was reversed by the 5 g kg−1 diet (C5). Furthermore, glutathione-S-transferase (GST) activity was maintained at the basal level in shrimp fed a 1 g kg−1 diet (C1) but reduced in those fed C3 and C5. We also identified a reduction in lipid peroxidation in shrimp fed the C3 and C5 diets. In the hepatopancreas, the GST activities and glutathione (GSH) levels were higher in shrimp supplemented with chitosan, which showed a protective effect. Saline stress and chitosan supplementation did not affect differential hemocyte counts. In conclusion, the results of this study suggest that dietary intake of chitosan could enhance some antioxidant defenses of L. vannamei farmed in a BFT system. Thus, the inclusion of at least 1 g kg−1 chitosan could represent a good alternative to improve defense mechanisms and stress resistance, and it could also contribute to the development of sustainable aquaculture. • Salinity stress induced oxidative stress in shrimp cultivated in the BFT system. • Chitosan supplementation improved different antioxidant responses in both the gills and hepatopancreas of L. vannamei. • Chitosan reduced lipid peroxidation in the gills of shrimp subjected to salinity stress. [ABSTRACT FROM AUTHOR]