Influence of Three Protein Sources on Performance of Grasscutters （Thryonomys swinderianus） Fed Diets with or without Fishmeal

An 8-week feeding trial was conducted to assess the effect of soybean meal （SBM）, groundnut meal （GNM） and blood meal （BM） addition in diets with or without （1%） fishmeal on the performance, N-digestibility and cost of production of growing grasscutters. Fifty-four grasscutters （9-week-old） of mixed sexes were randomly assigned to six dietary treatments, using a completely randomized design （CRD） in a 2 × 3 factorial arrangement, with three grasscutters per treatment and three replicates each. Treatments 1-3 （TI-T3） contained no fishmeal, whilst treatments 4-6 （T4-T6） had 1% fishmeal added. The diets were formulated to be isocaloric and isonitrogenous. N-digestibility was significantly high for SBM diets with or without fishmeal, 83.91% and 82.19%, respectively, followed by BM diets. Average daily gain （ADG） was significantly （P 〈 0.05） high （12.95 g） for BM diet without fishmeal. Feed cost per kg diet was the lowest （US$0.195） for the same BM diet. The results indicated that the inclusion of SBM and BM in the diet of grasscutters with or without 1% fishmeal could improve performance and it may be the most economical for feeding BM in the diet without fishmeal.

Influences of dietary protein sources and crude protein levels on intracellular free amino acid profile in the longissimus dorsi muscle of finishing gilts

Background： The current study was carried out to determine effects of dietary protein source and crude protein（CP）level on carcass characteristics, meat quality, and muscle amino acid（AA） profile in finishing gilts. The experiment was designed as a 2 × 2 factorial arrangement with two sources of dietary proteins（cottonseed meal, CSM vs. soybean meal, SBM） and two levels of CP（12 % vs. 14 %, as-fed basis）. Seventy-two crossbred gilts（89.5 ± 0.9 kg） were allotted to one of four dietary treatments in a randomized complete block design for a period of 28 d. All diets were formulated to be isoenergetic and similar concentrations of standardized ileal digestible essential AA covering the nutrient requirements of pigs.Results： Growth, carcass characteristics and meat quality were not affected by dietary protein source nor crude protein level（P ＆gt; 0.10） except that average daily feed intake was increased by CSM diets（P = 0.03）. Gilts offered reduced protein diets had lower muscle p H45min（P 〈 0.05）. Neither dietary protein source nor crude protein level influenced N deposition. However, reduced protein diets decreased N intake, N excretion, and serum urea nitrogen content, whilst improved N efficiency（P 〈 0.01）. CSM diets increased N intake（P = 0.04）,but did not depress N efficiency. The concentrations of phenylalanine, tryptophan, cysteine and tyrosine（P 〈 0.05） of the longissimus muscle were decreased when gilts offered CSM diets, while muscle intracellular free valine concentration was increased（P = 0.03）. The gilts offered reduced protein diets had greater intracellular concentrations of free methionine, lysine, and total AA in muscle（P 〈 0.05）.Conclusion： These results suggest that CSM could replace SBM as a primary protein source in finishing pig diets in terms of performance, N efficiency, carcass characteristics, and meat quality, but decrease the concentrations of muscle specific AA. Furthermore, the reduced protein diet played an important role in increasing muscle intracellular concentrations of specific free amino acids（FAA）, and in reducing the relative ratios of specific FAA to lysine in longissimus dorsi muscle of pig, whose biological meaning needs further studies.

Palatability of Water-Soluble Extracts of Protein Sources and Replacement of Fishmeal by a Selected Mixture of Protein Sources for Juvenile Turbot(Scophthalmus maximus)

Poor palatability is a limiting factor for replacing fishmeal with other protein sources in aquaculture. The water-soluble molecules with low molecular weights are the major determinants of the palatability of diets. The present study was conducted to investigate the palatability of water-soluble extracts from single protein source(single extract pellets) and the mixture of these extracts with different proportions(blended extract pellets) in juvenile turbot(Scophthalmus maximus). Then according to the palatability of blended extract pellets, an optimal mixture proportion was selected, and a new protein source made from raw protein materials with the selected proportion was formulated to replace fishmeal. Summarily, the palatability of single extract pellets for turbot was descendent from fishmeal to pet-food grade poultry by-product meal, wheat gluten meal, soybean meal, peanut meal, meat and bone meal, and corn gluten meal. Subsequently, according to the palatability of single extract pellets, 52 kinds of blended extract pellets were designed to test their palatability. The results showed that the pellets presented remarkably different palatability, and the optimal one was diet 52(wheat gluten meal: pet-food grade poultry by-product meal: meat and bone meal: corn gluten meal = 1:6:1:2). The highest ingestion ratio(the number of pellets ingested/the number of pellets fed) was 0.73 ± 0.03, which was observed in Diet 52. Then five isonitrogenous(52% crude protein) and isocaloric(20 k J g^(-1) gross energy) diets were formulated by replacing 0(control), 35%, 50%, 65% and 80% of fishmeal with No.52 blending proportion. After a 10-weeks feeding trial, a consistent feed intake was found among all replacement treatments. Replacement level of fishmeal up to 35% did not significantly influence final body weight, specific growth rate, feed efficiency ratio, and protein efficiency ratio of turbot. Therefore, the water-soluble extracts of protein sources play an important role in improving the palatability of non-fishmeal protein sources in aquafeed.

Fecal scores and microbial metabolites in weaned piglets fed different protein sources and levels

This experiment studied the effects of dietary protein sources and levels on the gut health of piglets,p H value,and concentrations of microbial metabolites(ammonia-N,volatile fatty acids [VFA],and polyamines) in the distal colonic and proximal colonic digesta of piglets weaned at 21 d of age.A total of 150 early-weaned piglets were allotted randomly to 5 diets: 1) control diet(CT; 17% CP),2) CT formulated with more soy protein concentrate(SPC19; 19% CP),3) more fish meal(FM19; 19% CP),4) CT formulated with more soy protein concentrate(SPC23; 23% CP),and 5) more fish meal(FM23; 23%CP).Results showed high protein level increased fecal score(P < 0.05),but different protein sources did not(P > 0.05).The p H value and ammonia-N concentration of digesta in the proximal and distal colon of FM23 were significantly higher(P < 0.05) than those of CT.Acetic acid,propionic acid,butyric acid and valeric acid concentrations in the proximal colon of FM23 exceeded those of CT,SPC19,and FM19(P < 0.05);however,isobutyric acid and isovaleric acid were not affected(P > 0.05).Histamine and spermidine concentrations of FM23 were higher than those of other treatments(P < 0.05).Propionic acid and butyric acid concentrations in the distal colon were higher of FM23 than of FM19(P < 0.05); putrescine,histamine and spermidine were higher of FM23 than of LP and FM19(P < 0.05).It was concluded that high dietary CP content increased microbial metabolites(ammonia-N,histamine,putrescine) in colonic digesta and aggravated piglets' diarrhea.

Different dietary protein sources influence growth performance,antioxidant capacity,immunity,fecal microbiota and metabolites in weaned piglets

The inclusion of high-quality proteins are commonly used in swine production.Our research investigated the effects of hydrolyzed wheat protein(HWP),fermented soybean meal(FSBM),and enzyme-treated soybean meal(ESBM)on growth performance,antioxidant capacity,immunity,fecal microbiota and metabolites of weaned piglets.A total of 144 piglets(weaned at 28 d)were allotted to 3 dietary treatments with 6 replicate pens per treatment and 8 piglets per pen.This study included 2 periods:d 0 to14 for phase 1 and d 15 to 28 for phase 2.Dietary treatments contained 15.90%HWP,15.80%FSBM,and 15.10%ESBM in phase 1,and 7.90%HWP,7.80%FSBM,and 7.50%ESBM in phase 2,respectively.The ADG of piglets in ESBM was increased(P<0.05)compared with HWP and FSBM during d 1e28.Compared with HWP and FSBM,ESBM increased(P<0.05)the ferric reducing ability of plasma(FRAP),and the serum level of superoxide dismutase(SOD)in piglets on d 14,as well as increased(P<0.05)the serum FRAP level in piglets on d 28.ESBM decreased(P<0.05)serum levels of DAO and IL-1b in piglets compared with HWP on d 28.ESBM enhanced(P<0.05)the relative abundance of Bacteroidetes,Oscillospiraceae and Christensenellaceae,as well as reduced the relative abundance of Clostridiaceae in the feces compared with HWP and FSBM.The PICRUSt analysis revealed that the number of gene tags related to degradation of valine,leucine and isoleucine,as well as lysine degradation in ESBM were lower(P<0.05)than that in HWP and FSBM.ESBM increased(P<0.05)the fecal butyrate level in piglets compared with FSBM,and ESBM tended to decrease(P=0.076)the fecal cadaverine level.Overall,ESBM had advantages over HWP and FSBM in improving antioxidant status,immune function,fecal bacteria and metabolites for weaned piglets.

Feasibility of Partial Replacement of Fishmeal with Proteins from Different Sources in Diets of Korean Rockfish(Sebastes schlegeli)

An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal(FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal(PBM), meat and bone meal(MBM), soybean meal(SBM), cottonseed meal(CSM) and canola meal(CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate(SGR) and survival rate(SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient(ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others(P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization.

Improving the nutritional values of yellow mealworm Tenebrio molitor(Coleoptera: Tenebrionidae) larvae as an animal feed ingredient: a review

Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Advances in the understanding of entomophagy and animal nutrition over the past decades have propelled research areas toward testing multiple aspects of YML to exploit them better as animal feed sources. This review aims to summarize various approaches that could be exploited to maximize the nutritional values of YML as an animal feed ingredient. In addition, YML has the potential to be used as an antimicrobial or bioactive agent to improve animal health and immune function in production animals. The dynamics of the nutritional profile of YML can be influenced by multiple factors and should be taken into account when attempting to optimize the nutrient contents of YML as an animal feed ingredient. Specifically, the use of novel land-based and aquatic feeding resources, probiotics, and the exploitation of larval gut microbiomes as novel strategies can assist to maximize the nutritional potential of YML. Selection of relevant feed supplies, optimization of ambient conditions, the introduction of novel genetic selection procedures, and implementation of effective post-harvest processing may be required in the future to commercialize mealworm production. Furthermore, the use of appropriate agricultural practices and technological improvements within the mealworm production sector should be aimed at achieving both economic and environmental sustainability. The issues highlighted in this review could pave the way for future approaches to improve the nutritional value of YML.

Effects of undigested protein-rich ingredients on polarised small intestinal organoid monolayers

Here, we describe the use of monolayers of intestinal epithelial cells derived from intestinal organoids and transcriptomics to investigate the direct effects of dietary protein sources on epithelial function. Mechanically dissociated 3 D organoids of mouse duodenum were used to generate a polarized epithelium containing all cell types found in the tissue of origin. The organoid-derived cell monolayers were exposed to 4%(w/v) of ‘undigested(non-hydrolysed)-soluble' fraction of protein sources used as feed ingredients [soybean meal(SBM) and casein], or alternative protein sources(spray dried plasma protein, and yellow meal worm), or controls for 6 h prior to RNA isolation and transcriptomics. All protein sources altered expression of unique biological processes in the epithelial cells. Exposure of intestinal organoids to SBM downregulated expression of retinol and retinoid metabolic processes as well as cholesterol and lipid biosynthetic pathways, consistent with the reported hypotriglyceridaemic effect of soy protein in vivo. These findings support the use of intestinal organoids as models to evaluate complex interactions between dietary ingredients and the intestinal epithelium and highlights some unique host effects of alternative protein sources in animal feed and potentially human food.

Food synthetic biology-driven protein supply transition: From animal-derived production to microbial fermentation

Animal-derived protein production is one of the major traditional protein supply methods,which continues to face increasing challenges to satisfy global needs due to population growth,augmented individual protein consumption,and aggravated environmental pollution.Thus,ensuring a sustainable protein source is a considerable challenge.The emergence and development of food synthetic biology has enabled the establishment of cell factories that effectively synthesize proteins,which is an important way to solve the protein supply problem.This review aims to discuss the existing problems of traditional protein supply and to elucidate the feasibility of synthetic biology in the process of protein synthesis.Moreover,using artificial bioengineered milk and artificial bioengineered eggs as examples,the progress of food protein supply transition based on synthetic biology has been systematically summarized.Additionally,the future of food synthetic biology as a potential source of protein has been also discussed.By strengthening and innovating the application of food synthetic biology technologies,including genetic engineering and high-throughput screening methods,the current limitations of artificial foods for protein synthesis and production should be addressed.Therefore,the development and industrial production of new food resources should be explored to ensure safe,high-quality,and sustainable global protein supply.

Research Progress in the Application of Feed Protein Source in Aquaculture

To replace fish meal for aquatic feed and develop new protein source are important requirements to ensure sustainable development of aquaculture industry and food security in China.This paper reviewed the application effects of common protein sources in aquatic animals and some new protein sources with promising application prospects in aquatic animals and the existing problems and solutions,and prospected the development direction of"non-food"new protein sources,hoping to provide reference for the research and technical personnel of aquaculture and aquatic feed production in the research and development of aquatic feed and protein source selection.

Analysis of Nutrient Profile of Finger Millet(Eleusine coracana(L.)Gaertn.)for Baby Food Formulation Using Pigeon Pea(Cajanus cajan(L.)Millsp.)as Protein Source

Finger millet(Eleusine coracana(L.)Gaertn.)is a drought resistant crop with potentially tremendous but under-explored source of nutraceutical properties as compared to other regularly consumed cereals in the era of drawback of nutritional security,these characteristics must be harnessed to develop finger millet as a novel functional food.Under-nutrition caused by inadequate diets,and other factors that influence nutritional status,is the underlying factor in 45%child deaths.In Kenya only 25%of young children are fed adequately diverse diets.The main objective of this study was to prepare baby food formulas using finger millets with pigeon peas as protein source and to analyze their nutritional profiles.Two finger millets varieties(i)Snapping Green Early,low altitude and medium altitude varieties and(ii)U-15)were studied to determine effects of environment on nutrient profiles.This study showed that Snapping Green Early had better nutrient profiles(12.13%protein and is high in Ca,Mg,Fe,Zn and P)than U-15(11.69%protein and lower nutrients(Ca,Mg,Fe,Zn and P)),and hence was selected for use in the malting process as best variety.As expected,the pigeon peas had the highest protein value(21%).The samples malted for 72 h resulted in reduction of tannin concentration from 0.091%to 0.03%and the amount of nutrients(Ca,Mg,Fe and Zn)doubled and in fact the protein profile increased by 8.31%.The appropriate ratio for the formulation of the baby food was 70:30.The composting resulted in 18.5%increase in protein.

The Performance of Black Soldier Fly Larvae (BSFLs), Hermetia illucens L. (Diptera: Stratiomyidae), as a Function of the Substrate Used: A Review

Organic wastes are one of the greatest challenges that cities face worldwide. In numerous underdeveloped nations, like Cameroon, waste is often disposed of through landfills, composting, or open-air combustion. Unfortunately, the concept of waste sorting and organic waste processing is new to many individuals. This has led to an increase in the amount of organic waste and the costs connected with its management. Consequently, the majority of developing nations have sought out waste management solutions that are more cost-effective. Therefore, it has been determined that the bioconversion of organic wastes by black soldier fly larvae (BSFLs) (Hermetia illucens) into multifunctional prepupae is a viable alternative. Appreciation is given to the employment of the organic waste management approach in developing nations since it is not only environmentally friendly and economically viable, but also provides a means for waste valorisation through the production of diverse resources and potential economic benefits. Studies have proved the usefulness of the insect in controlling organic wastes, but countries such as Cameroon are still unfamiliar with the nuances of this method. Consequently, this timely review examined the performance of the BSFL, specifically in organic waste treatment, as well as the best practices for multiplying them to determine its viability for use in a waste treatment plant, the production of high-quality larvae as a source of protein for livestock, and the production of diesel fuel.

Research progress on cottonseed meal as a protein source in pig nutrition:An updated review

At a global level,the supply of protein sources is insufficient to support the current magnitude of pig production.Moreover,given the exorbitant expense of conventional protein feed options like soybean meal and fish meal,it becomes imperative to promptly explore alternative sources of protein feed for the sustainable advancement of the pig industry.Cottonseed meal,a by-product from the extraction of cottonseed oil,exhibits significant potential as a protein source for pig feed owing to its high protein content,high yield,low cost,well-balanced amino acid composition,and sufficient accessibility.However,cottonseed meal possesses several anti-nutritional factors,especially gossypol,which adversely affect growth and reproductive performance,resulting in the limited utilization of cottonseed meal in pig feed.To maximize the benefits of cottonseed meal and promote its application in pig production,it is imperative to acquire comprehensive knowledge regarding its nutritional value and current utilization.In this review,we initially presented a summary of the nutritional values of cottonseed meal,primary anti-nutritional factors,and effective approaches for improving its utilization as a protein source feed.Subsequently,we comprehensively summarized the latest research progress of cottonseed meal application in pig nutrition over the past decade.The outcome of this review serves as a theoretical foundation and practical guidance for the research and application of cottonseed meal in pig nutrition and promotes the reduction of soybean meal utilization in the pig industry.

Review on Using of Housefly Maggots(Musca domestica)in Fish Diets

The main animal protein ingredient in fish diets is most often fishmeal because of its nutritional quality.However,the limited availability and increasingly cost of fishmeal has lead to investigations of either lowering or replacing the fishmeal content with more economic protein sources of animal and/or plant origin.The research for appropriate and cheap cost alternative sources of protein to use in commercial fish diets will be the most important factor in intensive fish culture development.Insect meals are healthy and nutritious alternatives to fish meal due to their rich nutritional values,particularly protein,fat and minerals.Housefly maggots(Musca domestica)meal is also rich in B complex vitamins,trace elements and phosphorus.From the results of previous studies,Housefly maggots meal can be used successfully to replace the fish meal portion partially or completely in the fish diets.Also,the results observed that not physiological stressful was introduced in the fish by feeding Housefly maggots meal diets.This indicates that Housefly maggots meal were well utilized by the fish thus resulting in good growth of fish.In other study,observed a best growth performance with fish feeding on diets containing maggot’s meal compared with fish feeding on fishmeal diet.This indicates the high nutritional quality and fish acceptance of maggot’s meal.

The Nutritional Value of Yellow Lupine (Lupinus luteus)for Growing Pigs

The aim of the study was a comparison of the composition and apparent total tract digestibility (ATTD) of nutrients in the seeds of two varieties of yellow lupine (YL). Moreover, an examination of the level of soybean meal (SBM) substitution by YL meal and in a combination with rapeseed meal (RSM) on the pigs’ performance was performed. In a digestibility trial, 30 male pigs were tested using a marker method. In two growth experiments, 60 pigs (in each) were fed diets where SBM was replaced by YL in 0%, 20%, 40%, 60%, 80% and 100% or by a mixture of RSM and YL or by both these components. The chemical composition of varieties differed among crude protein (CP), fiber, acid detergent fiber (ADF), neutral detergent fiber (NDF) and fat. The digestibility coefficients of protein, fat and gross energy were similar for both varieties. The substitution of SBM with YL did not negatively affect the pigs’ performance. A mixture of RSM with YL had no negative effect on growth parameters, except for the starter phase, when a level of above 15% RSM in the diet reduced the pigs’ gains. In conclusion, YL alone and with RSM may be a sustainable alternative to SBM in pig nutrition.

Effect of age on the standardized ileal amino acid digestibility of soybean meal and canola meal in broilers

Standardized ileal digestibility coefficients(SIDC)of nitrogen(N)and amino acids(AA)in two protein sources(soybean meal[SBM]and canola meal[CM])were investigated at six broiler ages(d 7,14,21,28,35,and 42).Two assay diets were formulated to contain either SBM(413 g/kg)or CM(553 g/kg)as the sole dietary AA source.Titanium dioxide(5 g/kg)was added as an indigestible marker.A total of 696 male broilers at 1 d old were allotted to 12 replicate cages per age group.Each assay diet was offered to birds for 4 d prior to the ileal digesta collection on d 7(14 birds/cage),14(12 birds/cage),21(10 birds/cage),28(8 birds/cage),35(8 birds/cage)and 42(6 birds/cage),respectively.The apparent digestibility coefficients were standardized using age-specific basal endogenous AA flows.In the SBM group,though the SIDC of N tended to be influenced(quadratic;P=0.075)by age,no linear or quadratic response of age effect was observed on the average SIDC of indispensable(IAA)and total AA(TAA).An age effect(quadratic;P<0.05)was observed on the average SIDC of dispensable AA(DAA)in SBM with the highest value recorded at d 7,followed by a decrease from d 14 to 28,which increased beyond d 35.The SIDC of some individual AA(Arg,Thr,Trp,Cys,Pro)were affected(P<0.05 or P<0.001)in a quadratic manner by age.In the CM,the SIDC of N,average SIDC of IAA,DAA and TAA were influenced(quadratic;P<0.05 or P<0.001)by age.The SIDC of N and average SIDC of DAA and TAA were higher from d 7 to 14,declined at d 21,and then increased beyond d 28.The average SIDC of IAA was low between d 7 and 28 and increased thereafter.The SIDC of individual AA were affected(linear or quadratic;P<0.05 or P<0.001)by different magnitudes by age.The age influence on the SIDC AA was variable,depending on the protein source and AA.The results demonstrate that age-specific SIDC AA data might need consideration in broiler feed formulations.

Demo-scale production of protein-rich fungal biomass from potato protein liquor for use as innovative food and feed products

Innovative food and feed products have recently attracted the attention of both producers and consumers.Filamentous fungi are important biomass producers with their high protein contents.In this study,fungal biomass production from edible potato protein liquor (PPL),generated during starch production processes,was investigated through different fungal strains (Rhizopus oryzae ,R.oligosporus ,R.delemar ,Aspergillus oryzae and Neurospora intermedia ).The effects of PPL concentration,incubation time,initial pH,and cultivation conditions (in shake flaks and different scale reactors) were examined to determine the amount of biomass and its crude protein level.It was determined that the fungal biomass produced by R.delemar in industrial scale contained 53% crude protein.For this strain,the amino acid and fatty acid profiles as well as metals (iron,manganese,copper,and zinc) of the produced biomass were also investigated to assess possible use as a food or feed source.The R.delemar fungal biomass can be a promising raw material for feed and food production,for example,considering its protein and fatty acid profiles with 41% essential amino acids and 33% polyunsaturated fatty acids.

Partial replacement of soybean meal by yellow mealworm(Tenebrio molitor)meal influences the flesh quality of Nile tilapia(Oreochromis niloticus)

This study investigated the effects of yellow mealworm meal(YM)replacing soybean meal(SBM)at different proportions(0%,15%,30%and 45%,referred as YM0,YM15,YM30 and YM45,respectively)on the flesh quality of Nile tilapia.A total of 360 fish(70.0±0.12 g)were randomly divided into 4 groups(3 tanks per group).Fish were fed the experimental diet twice daily for 10 wk.The results showed that muscle protein content significantly decreased in YM30 and YM45,while the lipid content significantly decreased in YM45(P<0.05).The essential amino acids and flavor amino acids of the muscle were not affected by the YM substitution,while saturated fatty acid content decreased in YM30 and YM45 compared with YM0(P<0.05).Fillets in YM45 had higher hardness,gumminess,and a higher proportion of thin myofibers(≤100μm,P<0.05)than those in other groups.Further analysis revealed that apoptosis and atrophy related genes were up-regulated,while the muscle antioxidant capacity decreased significantly in YM45(P<0.05),which may be related to the high acid value in YM45 diet.Our findings indicated that YM could replace up to 30%SBM without substantially altering the flesh quality.When the replacement ratio increased to 45%,the flesh quality would change.Special attention should be paid to avoid feed rancidity which may affect the flesh quality of fish.

Conversion of fish processing wastewater into fish feed ingredients through submerged cultivation of Aspergillus oryzae

Fish processing towards production of fillet gives rise to wastewater streams that are ultimately directed to biogas production and/or wastewater treatment.However,these wastewater streams are rich in minerals,fat,and proteins that can be converted to protein-rich feed ingredients through submerged cultivation of edible filamentous fungi.In this study,the origin of wastewater stream,initial pH,cultivation time,and extent of washing during sieving,were found to influence the amount of recovered material from the wastewater streams and its protein content,following cultivation with Aspergillus oryzae.Through culti-vation of the filamentous fungus in sludge,330 kg of material per ton of COD were recovered by sieving,corresponding to 121 kg protein per ton of COD,while through its cultivation in salt brine,210 kg of material were recovered per ton of COD,corresponding to 128 kg protein per ton of COD.Removal ranges of 12-43%,39-92%,and 32-66%for COD,total solids,and nitrogen,respectively,were obtained after A.oryzae growth and harvesting in the wastewater streams.Therefore,the present study shows the versatility that the integration of fungal cultivation provides to fish processing industries,and should be complemented by economic,environmental,and feeding studies,in order to reveal the most promising valorization strategy.

Recent advances in the utilization of insects as an ingredient in aquafeeds:A review

The aquafeed industry continues to expand in response to the rapidly growing aquaculture sector.However,the identification of alternative protein sources in aquatic animal diets to replace conventional sources due to cost and sustainability issues remains a major challenge.Recently,insects have shown tremendous results as potential replacers of fishmeal in aquafeed.The present study aimed to review the utilization of insects in aquafeeds and their effects on aquatic animals’growth and feed utilization,immune response and disease resistance,and fish flesh quality and safety.While many insect species have been investigated in aquaculture,the black soldier fly(Hermetia illucens),and the mealworm(Tenebrio molitor)are the most studied and most promising insects to replace fishmeal in aquafeed.Generally,insect rearing conditions and biomass processing methods may affect the product’s nutritional composition,digestibility,shelf life and required insect inclusion level by aquatic animals.Also,insect-recommended inclusion levels for aquatic animals vary depending on the insect species used,biomass processing method,and test organism.Overall,while an appropriate inclusion level of insects in aquafeed provides several nutritional and health benefits to aquatic animals,more studies are needed to establish optimum requirements levels for different aquaculture species at different stages of development and under different culture systems.