Tom 23 (2023): Zeszyt 1 (January 2023)

The increasing global population tends many sectors to overcome the food security issue; sustainable aquaculture is one of the systems that reveal the food problem in the world. The aquaculture industry is drastically increasing to offer the growing demand for this food type. The high mortalities threaten this sector during the first larval stages because of the low supplies of suitable feed for the fish larva. Artemia is vital for the aquaculture industry as it is the primary feed source for fish larvae; it is distinguished by its small size, food carrier characteristic, and off-the-shelf food feature. However, the principal source of artemia cysts has been affected by climate change, ultimately affecting artemia cyst production. Consequently, many areas worldwide try to produce artemia locally to satisfy the aquaculture rearing requirements. As a feed transmitter, artemia can be enriched with essential elements to feed the fish larvae; this method increases survivability, growth performance, and other growth indicators for many fish species. This review aimed to update the academia and stakeholders involved in artemia production in relation to the aquaculture industry. An updated overview of artemia production is also presented in the current review.

Today, the increase of the world’s population and climate change has resulted in the reduction of fresh water resources and the increase of arid and semi-arid areas, and thus, it is necessary to find a new solution to increase the production of food resources. Aquaculture is one of the sources of food production, which can play a key role in fighting poverty and hunger. Sustainable aquaculture is strongly dependent on water quantity and quality, and also, optimal fish production can be determined by the physical, chemical and biological quality of water. Due to the current restrictions and the global increase in demand for aquatic products, unconventional waters (UWs) have been used in aquaculture. UWs include: recycled water, sewage, saline water, agricultural drains and water resulting from the process of sweetening and desalination of salty water. Today, these water resources have been used to grow all kinds of aquatic animals to provide food and protein. Considering the limited water resources in the world, the use of UWs is very effective and efficient in managing drought, and is considered as one of the ways to develop food production for humans. Due to its importance in areas facing water scarcity, the use of unconventional water resources (UWRs) to supplement or replace the use of conventional fresh water sources has been considered. In this review study, the importance of UWs and their sources, aquaculture products and aquatics that can be cultivated with the help of UWs are discussed.

Million tonnes of agricultural waste are generated annually worldwide. Agricultural wastes possess similar profiles to the main products but are lower in quality. Managing these agricultural wastes is costly and requires strict regulation to minimise environmental stress. Thus, these by-products could be repurposed for industrial use, such as alternative resources for aquafeed to reduce reliance on fish meal and soybean meal, fertilisers to enrich medium for growing live feed, antimicrobial agents, and immunostimulatory enhancers. Furthermore, utilising agricultural wastes and other products can help mitigate the existing environmental and economic dilemmas. Therefore, transforming these agricultural wastes into valuable products helps sustain the agricultural industry, minimises environmental impacts, and benefits industry players. Aquaculture is an important sector to supply affordable protein sources for billions worldwide. Thus, it is essential to explore inexpensive and sustainable resources to enhance aquaculture production and minimise environmental and public health impacts. Additionally, researchers and farmers need to understand the elements involved in new product development, particularly the production of novel innovations, to provide the highest quality products for consumers. In summary, agriculture waste is a valuable resource for the aquafeed industry that depends on several factors: formulation, costing, supply, feed treatment and nutritional value.

Tomato cultivation and industrial processing produce a considerable amount of tomato pomace, peels, and seeds, which are difficult to handle. These by-products contain a variety of minerals and bioactive substances, and may thus be further valorised, generating additional revenue for processing plants while also decreasing environmental issues caused by their buildup. The inclusion of tomato pomace in poultry feed has been shown to produce promising effects in poultry growth and health, however the results are largely inconsistent. Literature has documented improvement in growth, egg production and quality, immunological and antioxidant effects in poultry. This review has compiled the impacts of tomato pomace on the growth and health indices of poultry.

The prohibition of antibiotic growth promoters (AGP) and the restriction of synthetic antioxidants have had a negative impact on the productivity and health of broiler chickens. To ensure sustainability in broiler production, poultry nutritionists continue to look for alternatives to AGP and antioxidants. Using herbal ingredients is one alternative that is widely used today. However, the use of herbal ingredients in small doses is often constrained by bioavailability problems, thereby reducing the effectiveness of using herbal additives for broiler chickens. At higher doses, the use of herbal ingredients can increase feed costs and negatively impact palatability, digestion and protein utilization, and liver health. Encapsulation is a method that can improve the stability, palatability, and bioavailability of herbal additives, which may enhance the efficacy of herbs as AGP and antioxidant alternatives for broilers. This review article provides a comprehensive insight into the application of and problems related to herbal additives, benefits of encapsulation technology on herbs, and use of encapsulated herbs in broiler production.

The deacetylation of chitin results in chitosan, a fibrous-like material. It may be produced in large quantities since the raw material (chitin) is plentiful in nature as a component of crustacean (shrimps and crabs) and insect hard outer skeletons, as well as the cell walls of some fungi. Chitosan is a nontoxic, biodegradable, and biocompatible polyglucosamine that contains two essential reactive functional groups, including amino and hydroxyl groups. This unique chemical structure confers chitosan with many biological functions and activities such as antimicrobial, anti-inflammatory, antioxidative, antitumor, immunostimulatory and hypocholesterolemic, when used as a feed additive for farm animals. Studies have indicated the beneficial effects of chitosan on animal health and performance, aside from its safer use as an antibiotic alternative. This review aimed to highlight the effects of chitosan on animal health and performance when used as a promising feed additive.

The large intestine epithelium plays an important role in water absorption and participates in fluid, acid-base and electrolyte balance, and the removal of waste products. The large intestine is rich in microorganism-presented enzyme activity. Apart from energy supply, the colon also participates in the synthesis of trophic factors and the modulation of the immune system and the systemic inflammatory response. The current study investigated the effects of dietary HMB administration to pregnant sows on the postnatal development of the colon in their offspring, at weaning. From the 70th to the 90th day of gestation, sows received either a basal diet (n = 12) or the basal diet supplemented with HMB (n = 12) at a dose of 0.2 g/kg of body weight/day. Maternal HMB treatment increased serum IgG and glucose concentrations and decreased serum urea concentration in the piglets. Basal histomorphometric analysis of offspring large intestines showed that prenatal HMB treatment led to a reduction in the thickness of the mucosa, submucosa and both types of myenterons, as well as reduced crypt thickness. The immunoreaction performed to mark T0 lymphocytes and total T lymphocytes in the colon wall showed that prenatal HMB treatment decreased the number of both types of lymphocytes. Greater expression for cadherin was found in the colon of piglets delivered by the HMB-treated sows. The expression of both tight junction proteins (occludin and claudin-3), as well as that of leptin, was stronger in the HMB-treated group. Vasoactive intestinal peptide (VIP) expression was stronger in the submucosal plexuses in the HMB maternal treated piglets, while no changes were observed in the myenteric plexuses. The results obtained indicate that the administration of HMB to pregnant sows significantly influenced the expression of leptin, VIP and some proteins of the intestinal barrier in their offspring, with less influence on large intestine basal morphology.

The present study evaluated the health status of rainbow trout (30.24±5.34 g) acclimated to high-saline water (28‰). Among adaptation procedures, gradually-acclimated (for 48 h) fish showed best performance, which were then introduced to the offshore cage-farm for further monitoring of fish health in marine environment over a long-term period of 100 days, until harvest weight of 319.9±48.51 g. Fish health and welfare was evaluated by means of biochemical parameters (viscerasomatic index, hepatosomatic index, mesenteric fat index, and spleen somatic index), hematological parameters (serum glucose, triglyceride, cholesterol, total protein, albumin, globulin), and immune parameters (lysozyme, myeloperoxidase, respiratory burst and potential killing values). Gradual acclimation to high-saline water did not show any adverse effects on health parameters. No significant differences were found in biometric measures (P>0.05). However, a time-dependent increase was recorded in hematology markers (P<0.05) after seawater transfer, and the health status improved over long term from March 7 to June 14, 2018. All serum biochemical markers, except the total protein showed significant alterations (P<0.05) in long term but without detrimental influence by day 100. Therefore, it seems possible to expand trout farms from brackish water sites to higher saline environments up to 28‰ salinity, with no detrimental impacts on fish health, that in turn may significantly contribute to the extension of potential aquaculture sites to wider areas.

The objective of this study was to evaluate the prevalence and diversity of Enterococcus spp. and antibiotic-resistant Enterococcus faecalis and Enterococcus faecium isolates in different foods worldwide. This study used meta-analytical methods. Besides, Web of Science (n= 705), Medline (n= 6), and Scopus (n= 1338) were searched for studies in the years 1995–2021 using related keywords. Results showed that the pooled prevalence for Enterococcus spp. and antibiotic-resistance of E. faecalis and E. faecium isolates were 0.41 (95% C.I. 0.34–0.47), 0.25 (95% C.I. 0.13–0.38), respectively. According to the results of the subgroup analysis, the lowest and highest prevalence of Enterococcus spp. in food types were calculated for red meat (0.56), and fermented foods (0.29). Also, as a result of subgroup analyses by country the highest prevalence of Enterococcus spp. was calculated in studies conducted in Slovakia (0.74). In contrast, the lowest prevalence was calculated in studies conducted in Georgia (0.07). The meta-analyses improved our understanding of the prevalence of Enterococcus spp. and the antibiotic resistance of E. faecalis and E. faecium isolates in different foods and provided results that can be useful as input for quantitative microbiological risk evaluation modeling.

In the current study the hypothesis that 1.0% dietary inclusion of glutamine (Gln), a conditionally essential amino acid that influences protein synthesis and shows anti-osteoporotic effect, can influence eggshell quality was tested on laying hens in the post-peak laying period. Thirty-week-old Bovans Brown hens were randomly assigned to control group or group supplemented with Gln in the form of alphaketoglutarate (10 g/kg) with 12 replicate cages (2 hens/cage) in each group. The experimental period lasted for 30 weeks, from the 31st to the 60th week of age of hens, when eggs were collected and selected eggshell quality indices were determined. While Gln supplementation had no effect on egg geometry and eggshell cracking force, the analysis of eggshell quality showed an increase of the eggshell thickness (P<0.01), porosity (P<0.01), eggshell specific surface (P<0.001) and positive changes in other mechanical parameters (decrease of eggshell stiffness and Young’s modulus, P<0.05 and P<0.01, respectively; increase of work needed to crack the eggshell, P<0.05). Changes in eggshell mineral composition, including an increase of Ca content (P<0.001), were also observed. In conclusion, the current study showed a beneficial effect of Gln on the eggshell thickness, calcification, and some mechanical parameters.

The aim of this study was to determine the effect of halloysite supplementation to the complete diets for broiler chickens on selected blood parameters, carcass and organ characteristics, as well as bone and meat traits. The trial was conducted under experimental conditions in a large-scale poultry farm on 18,000 broiler chickens. The one-day broiler Ross 308 chicks were randomly divided into two groups: control (C) and experimental (E) in an amount of 9,000 birds per group. In each group, chicks were separated into five pens (100 m²) with 1800 chicks per pen. The birds were fed granulated complete mixtures without (C group) or with halloysite (E group) distributed in an amount of 1% (based on fresh matter) from the 11 d of life. Analysis revealed that halloysite supplementation to the broiler diet at the level of 1% showed a trend (P = 0.056) towards higher final body weight, significantly improved carcass yield (P = 0.048), and reduced the relative weights of the liver and gizzard (P<0.05). No differences (P>0.05) were observed either in terms of the physicochemical parameters of the broiler chickens’ breast muscles, except a significantly lower b* value of the colour parameter (P = 0.048). In turn, in the blood serum, the addition of 1% halloysite significantly decreased (P<0.05) the content of triglycerides and the total cholesterol and low-density lipoprotein fraction, but did not affect (P>0.05) the high-density lipoprotein fraction, calcium, phosphorus or alkaline phosphate content. Tibia and femur characteristics (weight, length, relative bone weight, bone mineral density, bone mineral content, and breaking strength) were not affected (P>0.05) by the usage of halloysite. In conclusion, supplementation of broiler diet with halloysite in the amount of 1% had beneficial effects on the carcass yield and health status of the animals, without any adverse effect on the bone parameters or meat quality of the broiler chickens.

The study determined the effect of introducing 50% of protein from the protein feed pool derived from raw chickpea seeds (CPR) instead of 50% of soybean meal (SBM) in the rearing period from day 22 to 42 on the coefficients of nutrient digestibility, growth performance, selected carcass traits, the hematological and metabolic profile of blood, and the quality of femur bones in male Ross 308 broilers. The study was carried out on 200 22-day-old male Ross 308 broiler chicks (initial weight of 756 g) randomly assigned to two groups (n=100 in each group; 5 cages with 20 birds each). All birds were reared for 42 days. They were fed isonitrogenous and isoenergetic pre-experimental starter diet (day 1 to 21) in crumble form and experimental grower-finisher diets (day 22 to 42) in pelleted form. From rearing day 22, SBM male broilers (grower/finisher) were fed diets with 100% SBM as a protein source. In the diet for the CPR group (grower and finisher), the SBM protein was replaced with 50% of CPR-derived protein. During the grower and finisher stage and between days 22 and 42, the CPR group exhibited significant (P=0.032) reductions in feed intake (FI), higher (P=0.043) slaughter yields, high (P=0.044) % share of breast muscles, and reduced (P=0.003) abdominal fat content. The addition of CPR influenced some blood parameters. The level of total protein, urea, and Mg decreased, whereas the activity of alkaline phosphatase (ALP) and aspartate transaminase (ALT ) increased. In the CPR group, an increase in the physical, morphometric, and some strength parameters of the femur (maximum elastic strength – Wy, yielding deformation – dy, bone density index – BDI, and Young’s modulus) was observed. Therefore, CPR may be a promising partial substitute of SBM in broiler nutrition, as it enhances production performance and has a beneficial effect on bone quality.

The aim of this study was to determine the effects of dietary supplementation with black cumin seed meal on growth performance parameters, coccidia oocyst counts, plasma biochemical parameters and cecal fermentation processes in growing rabbits. A total of 40 male Californian rabbits at 35 days of age were divided into two feeding groups: Control (complete rabbit diet) and Black cumin (2% of the complete diet was replaced with black cumin seed meal). Dietary supplementation with black cumin did not affect growth performance parameters, but it reduced coccidia oocyst counts in the feces of 63-day-old rabbits. Increased liver weight and elevated plasma albumin levels were noted in these rabbits. A significant decrease in small intestinal digesta viscosity was also observed in rabbits fed a diet supplemented with black cumin seed meal. The above change suppressed the formation of putrefactive compounds, i.e. ammonia and branched short-chain fatty acids (SCFA s) in the cecum, but it did not decrease the production of major SCFA s, i.e. acetic, propionic and butyric acids. The current study demonstrated that the dietary addition of 2% black cumin seed meal exerted a modulatory effect on gastrointestinal function, but it did not compromise microbial enzyme activity or SCFA production in the cecum.

Fiber digestibility is a key-point of forage usage in ruminant production systems. The present study aimed to evaluate the effect of fibrolytic enzyme blend on whole-plant sorghum silage fermentation profile, fermentative losses, chemical composition, in vitro degradation, and aerobic stability. It used fifty experimental silos (plastic bucket, 28 cm i.d. and 25 cm in height) in a blocked randomized design to evaluate the following fibrolytic enzyme levels: 0, 150, 300, 450, and 600 mL per ton of dry matter (DM). Enzymes had 300 U/mL of xylanase and 300 U/mL of cellulase. Enzymes linearly increased acetic acid, branched-chain organic acids, and ethanol concentration of silage. Although there was no treatment effect on silage DM recovery over the ensiling process, enzyme levels linearly increased gas, effluent, and total losses. Intermediary levels of enzymes (from 312 to 342 mL/ton DM) decreased fiber content (NDF and ADF), whereas improved NFC silage content. Besides, enzymes did not affect DM and NDF degradation and tended to linearly reduce acid detergent fiber in vitro degradation. The enzymes addition linearly decreased silage temperature after aerobic exposure. However, there was no treatment effect on silage pH after aerobic exposure also during the time that silage remained with a temperature lower than 2°C above environmental temperature. Thus, fibrolytic enzymes reduce fiber content, promote a heterolactic fermentation, and reduce silage temperature after aerobic exposure. However, this increases fermentative losses and has no positive effect on in vitro degradation and the time of aerobic stability.

This study aimed to verify whether the inclusion of 0.5 kg full-fat rice bran per day in the diet of geriatric horses will improve their condition, increase the population of methanogens in the cecum, and thus affect the biochemical blood parameters. The experiment included 2 research periods: 6 healthy, non-working horses over 20 years of age (480 ± 20 kg of body weight) fed only hay (±8.86 kg/day/head) in the first period and hay (±8.00 kg/day/head) and rice bran (0.5 kg/day/head) in the second one. Each of these periods lasted 4 months. The Body Condition Scoring (BCS) assessment was performed at the beginning and end of the experiment. Blood and feces samples were collected on the first and last day of each period. After feeding with the addition of rice bran, BCS increased by 1.17 units on a 9-point scale. The experiment showed an increase in the total number of bacteria and methanogens inhabiting the cecum of horses. This can lead to better digestion of carbohydrates, absorption of nutrients, and, consequently, increased body weight. No differences occurred in the hematology and serum biochemistry indices of horses fed a diet including rice bran, except for the amount of serum globulin and the albumin to globulin ratio. Rice bran affected essential serum fatty acid profile (increased PUFA and decreased MUFA), which confirmed the possibility to use diet as a serum fatty acids profile modulator.

The effects of a functional additive (Sanacore^® GM; SAN) on immune and antioxidant indices, and the resistance of gilthead seabream (Sparus aurata) against Vibrio alginolyticus infection were investigated. For this, four diets containing 0% (the control), 0.1%, 0.2%, and 0.4% SAN were offered to triplicated groups of fish (20–23 g) for ten weeks. Subsequently, fish were injected intraperitoneally with V. alginolyticus and monitored for further ten days. Feeding the fish on SAN-supplemented diets showed positive effects on leukocyte counts and its differential percentages. Serum lysozyme activity and total immunoglobulin values, as well as blood phagocytic activity and indices, were linearly and quadratically higher in SAN-fed fish, especially at the 0.4% SAN diet. Similarly, linear and quadratic increases in catalase, superoxide dismutase, and total antioxidant capacity were observed in SAN-fed fish, particularly at the 0.4% SAN diet. Conversely, malondialdehyde values decreased in SAN-fed fish compared with the control group, which showed its highest value. The highest expression of the IL-1β gene coupled with the lowest TNF-α and HSP70 genes expressions was found in the fish fed with the 0.4% SAN. On the other hand, fish fed on the control diet showed the lowest IL-1β gene coupled with the highest TNF-α and HSP70 genes expressions. After bacterial infection, most of the control fish died with a relative percent of survival of 5.0%; meanwhile feeding gilthead seabream on SAN-enriched diets significantly enhanced their protection against V. alginolyticus infection fed on the 0.4% SAN diet showed 100% survival. The SAN administration to gilthead seabream especially at the 0.4% level led to significant promotions in antioxidative and immune responses and augmented the fish resistance to V. alginolyticus infection.

The purpose of the present study was to investigate the effects of amino acids L-proline and L-alanine on growth performance, amino acid, and fatty acid levels in the fillet of juvenile common carp. Four hundred and fifty juvenile common carp were randomly distributed in 30 tanks and fed with three levels of proline (5 [P5], 10 [P10], and 15 [P15] g/kg), three levels of alanine [A] (5 [A5], 10 [A10], and 15 [A15] g/kg), three levels of proline-alanine combination [PA] (2.5 + 2.5 [2.5PA], 5 + 5 [5PA], 7.5 + 7.5 [7.5PA] g/kg feed) and basal diet (control). The highest body weight gain (25.85 ± 0.1 g) and survival rate (91.11 ± 3.84) were observed in 7.5 PA treatment. The highest protein content (64.58 ± 0.49) was noticed in 2.5 PA; however, compared to combined treatments (5 PA and 2.5 PA), it did not show any significant difference (P<0.05). The highest total amount of essential amino acids (48.30 ± 48.3) was observed in 7.5 PA treatment. The highest amount of DHA (5.65 ± 0.08), total EPA, and DHA (8.91 ± 0.13) were in 7.5 PA treatment. Finally, it can be concluded that two amino acids L-proline and L-alanine at the combined level of 5 PA can improve the growth performance, survival, and fillet composition in the juvenile common carp.

It has been illustrated that using mixtures of feed additives is more efficient than using individual additives in aquaculture. Hence, this study aimed to study a dietary mixture of betaine, lactic acid bacteria, and exogenous digestive enzymes (BLE) on the growth performance, digestion capacity, intestinal health, and blood indices of Nile tilapia reared outdoors in concrete tanks. Five diets were prepared where the basal diets were mixed with BLE at 0, 0.25, 0.5, 0.75, and 1%. After 90 days, the growth performance of Nile tilapia fed BLE was markedly enhanced in fish fed 0.25 and 0.5% of BLE, while the feed conversion ratio (FCR) was reduced (P<0.05). The lipase activity was significantly higher in tilapia fed BLE at 0.25, 0.5, and 0.75% than 0 and 1%. The amylase activity was meaningfully increased by 0.5% of BLE than 0, 0.25, 0.75, and 1%. The protease activity was significantly higher in tilapia fed BLE at 0.25 and 0.5 than 0, 0.75, and 1% (P<0.05). The intestine of fish fed on BLE showed an increase in intestinal villi density. The villi length, width, and the number of goblet cells were markedly higher in the anterior, middle, and posterior segments of the intestines of tilapia fed BLE than in the control group (P<0.05). Further, fish fed BLE had higher intestinal morphometry indices and count of goblet cells than the control. Significantly fish fed 0.25, and 0.5% of BLE had higher hemoglobulin, and hematocrit levels than fish fed 0, 0.75, and 1%. While, fish fed 0.5% had higher red blood cells than fish fed the remaining BLE levels (P<0.05). On the other hand, no marked effects for BLE supplementation were seen on the alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein, albumin, globulin, creatinine, uric acid, and urea. The regression analysis showed that the maximum dose of BLE supplementation to achieve the highest final weight and the lowest FCR is 0.46% and 0.42%, respectively.

A trial was conducted to evaluate the effect of dietary grape seed proanthocyanidin extract (GSPE) on goldfish, Carassius auratus. In this regard, GSPE was added to a basal diet at four levels including 0, 200, 400, and 600 mg/kg to produce four experimental diets including control, GSPE200, GSPE400, and GSPE600. Three hundred and sixty goldfish (3.75 ± 0.1 g) were stocked in twelve 100 L rectangular tanks (30 fish per tank) and fed with the experimental diets three times a day for nine weeks. During the experimental trial, water temperature was 26.7–28.5°C. The weight gain and specific growth rate in the fish fed with GSPE supplemented diets were higher than the control, meanwhile feed conversion ratio value in these groups decreased compared to the control. Fish fed GSPE-supplemented diets had lower fillet lipid (10–19%), but higher protein levels (7–15%) compared to the control. The levels of serum triglyceride, alanine aminotransferase and aspartate aminotransferase in the fish fed GSPE-supplemented diets were decreased compared to the control group. The highest and lowest levels of serum glucose, and ALP were in the fish fed with control and GSPE600 diets, respectively. The skin mucosal lysozyme activity (24–38%) and protein level (70–96%) were higher in fish fed GSPE-supplemented diets than the control. The highest, and lowest liver antioxidant enzymes including superoxide dismutase, catalase, and glutathione peroxidase were observed in GSPE 600 and control groups, respectively. The findings of the present study indicated that supplementing 400 mg/kg GSPE in diet can improve growth and health condition in goldfish.

Black soldier fly larva meal (BSFM) application as an innovative feed material has been developed in aquaculture nutrition. However, recent scientific literature is still lacking in the case of insect meal effects on different stages of salmonid fish, and the vast majority of research is focused on farmed Atlantic salmon. Therefore, the holistic approach was undertaken in the cycle of two studies carried out: on fries and pre-smolts. This study aimed to evaluate the effect of fish meal (FM) replacement by full-fat BSFM in Atlantic salmon fry diets on the growth performance, feed utilization, crude protein and crude fat digestibility, somatic indices, histomorphology of intestines, and environmental sustainability. Additionally, pellet quality was assessed. Two experiments were performed on 360 Atlantic salmon fries – each of which lasted 60 days. For the first experiment, 240 individuals were distributed to four experimental groups: six replicates (tanks) per group and 10 fish per tank. For the second experiment, 120 individuals were distributed to four experimental groups: three replicates (tanks) per group and 10 fish per tank were used. The following groups were applied: CON – without the addition of full-fat BSFM and with 39% FM; BSFM5 – with 5% addition of full-fat BSFM and 36.1% FM; BSFM10 – with 10% full-fat BSFM and 33.3% FM; BSFM15 – with 15% addition of full-fat BSFM and 30.3% FM. The present study showed satisfactory results of BSFM inclusion at the levels of 5% and 10% as a replacement for fish meal in feeds for Atlantic salmon fries. No negative effects on growth performance, feed utilization, protein and fat digestibility, or intestinal structure were recorded. Simultaneously, insect meal inclusion in Atlantic salmon diets significantly improved the environmental sustainability of the feed. In the case of BSFM15, decreases in body weight gain, protein lipid efficiency ratio, and lipid efficiency ratio, as well as increases in feed conversion ratio, were observed. Therefore, the use of shares higher than 10% of BSFM in Atlantic salmon fries may not be recommended.

Black soldier larva meal (BSFM) seems to be a competitive protein and fat source for widely used fish meal (FM) and fish oil. Because of the still present problem of overfished seas and oceans for feed purposes, even a low substitution of the mentioned feed materials could have a positive impact on the environment. Due to the specificity of salmon metabolic processes, with particular attention to smoltification and the various requirements for nutrients related to individual stages, it is important to implement similar dietary inclusion levels of innovative feed materials in different life stages of Atlantic salmon. Thus, a holistic approach was undertaken in the cycle of two studies carried out: on fries and pre-smolts. This study aims to evaluate the effect of FM replacement by full-fat BSFM in Atlantic salmon pre-smolt diets on growth performance, feed utilization, somatic indices, histomorphology of intestines, colorimetric assessment and raw meat quality, as well as environmental sustainability. The following groups were applied: CON – without addition of full-fat BSFM and with 30% FM; BSFM5 – with 5% addition of full-fat BSFM and 27.1% FM; BSFM10 – with 10% full-fat BSFM and 24.3% FM; and BSFM15 – with 15% addition of full-fat BSFM and 21.3% FM. The present study showed satisfactory results of BSFM inclusion up to 15% as a replacement for FM in feeds for Atlantic salmon pre-smolts. The present study showed that BSFM is a suitable feed material for Atlantic salmon proper diet balancing and may be used to decrease FM content. The semi-technical application of BSFM containing diets confirmed their effectiveness during the growth phase of Atlantic salmon. According to our results, BSFM can be recommended as an alternative feed component in Atlantic salmon pre-smolt nutrition at levels up to 15%. Simultaneously, insect inclusion significantly improved the environmental sustainability of the rearing process.

To sustain normal development, high survival, and rapid growth, marine fish larvae require a diet rich in polyunsaturated fatty acids, which could decrease the risk of reactive oxygen species accumulations. Consequently, a 60-day feeding experiment was conducted to determine the effect of silymarin (SM) supplementation in weaning diets on the growth performance, survival, antioxidant enzyme activities, and fatty acids profile of European seabass (Dicentrarchus labrax) larvae. Four isonitrogenous and isolipidic diets were investigated using SM at levels of 0, 200, 400, and 600 mg kg⁻¹ (SM_0.00, SM₂₀₀, SM₄₀₀, and SM₆₀₀, respectively). The findings showed that, in a dose-dependent manner, increasing dietary levels of SM enhanced survival, growth, and feed utilization. In the SM₆₀₀ group, the weight gain, survival, and feed conversion ratio (FCR) improved by 123.21, 11.66, and 38.72%, respectively, compared to the control group. The dose-response analysis demonstrated a strong positive correlation (R2=0.96) between SM levels and weight increase, and a strong negative correlation (R2=0.88) between SM levels and FCR. The antioxidant enzyme activities of larvae given SM-enriched diets were significantly greater than those of the control group. Compared to the control group, the CAT and SOD improved by 81.77 and 5.08% in the SM600 group. In addition, the saturated fatty acid content decreased while the unsaturated fatty acid content increased, particularly in the SM600 group. The results indicate that supplementing the micro diet of European seabass larvae during weaning with SM at a dose of 600 mg kg⁻¹ increases growth, survival, antioxidant status, and fatty acid profiles.

The aim of this study was to evaluate the relationships between some physicochemical properties and organoleptic assessments of duck meat quality and expert assessment of the general appearance of raw breast and leg muscles. Body, carcass, breast and leg muscle weight were analysed. For both breast and leg muscles the following parameters were recorded: water holding capacity, thermal drip, colour lightness L*, electrical conductivity after 15 minutes and 24 hours post mortem, as well as four traits subject to expert organoleptic evaluation (general appearance, colour, odour and fatness). The dependence was evaluated using the Pearson’s correlation and multiple regression equations (the general appearance was treated as a dependent variable). Three sets of variables were considered as factors influencing the general appearance of the raw breast and leg muscles. First, the influence of jointly selected performance traits and physicochemical properties of meat was analysed. Next, the impact of only the second-mentioned group of discriminants was considered, and then the dependence on other organoleptic attributes. It was shown that for both muscle groups, the following have a significant effect on the general appearance: muscle weight (breast muscle P<0.0001, leg muscle P<0.0001) in the first set, electrical conductivity 15 minutes after slaughter (breast muscle P = 0.023, leg muscle P = 0.042) in the second, and colour (both muscle groups P<0.0001) in the third. Muscle weight, electrical conductivity 15 minutes post mortem and visually assessed colour can be used to make a preliminary assessment of the technological and culinary quality of duck meat. Moreover, measurement with a conductometer is an economical and fast method, possible to carry out in a slaughterhouse.

The purpose of this study was to evaluate the quality of mountain sheep milk obtained from animals kept on mountain pastures: natural and organic. The experimental procedure was conducted under production conditions, during annual grazing of mountain sheep on two mountain pastures in the region of the Polish Carpathians: on organic pasture certified for organic farming and natural mountain pasture belonging to the National Park. This study showed greater plant species diversity in the organic mountain pasture, but its yielding was lower than that of the natural pasture. The sward of the natural pasture was characterised by lower dry matter and fibre content but contained more total protein. The type of pasture did not affect the basic composition of the milk of mountain sheep, while differences were found in terms of acidity, alcohol number, fatty acid profile of fat and milk protein fractions. Milk obtained from sheep grazed on organic pasture was characterised by a higher proportion of medium chain fatty acids, as well as polyunsaturated fatty acids, and also essential unsaturated fatty acids, both linoleic acid, α-linolenic acid, γ-linolenic acid and arachidonic acid. In milk originating from the natural mountain pasture, a higher proportion of monounsaturated fatty acids, docosahexaenoic acid and the CLA c9-t11 isomer was found. The composition of milk protein fractions varied according to the location of grazing: milk from sheep grazing on natural pasture had a higher content of whey fractions, important for consumer health, milk from organic pasture had a higher content of κ-casein, of greatest importance in dairy processing technology. The floral composition of the pasture had an influence on the quality of sheep milk in relation to the fatty acid profile of fat and protein fractions of milk, which is important in terms of both the health-promoting and technological aspects of the raw material and may affect the quality of products made from it.