Feed Utilization Research Articles

Effect of L-carnitine supplementation on growth performance, feed utilization, body composition, and antioxidant capacity of large yellow croaker, Larimichthys crocea, fed at two dietary lipid levels

Effect of L-carnitine supplementation on growth performance, feed utilization, body composition, and antioxidant capacity of large yellow croaker, Larimichthys crocea, fed at two dietary lipid levels

Effects of replacing fish meal with pork meal and supplementing with crystalline amino acids and fish oil on growth performance, body composition, enzyme activity, intestinal morphology, and immune response of Penaeus monodon

IntroductionThe present study aimed to evaluate the effects of substituting fish meal with pork meal in feed on the growth performance, feed utilization, intestinal morphology, and immune function of Penaeus monodon.MethodsA total of 600 uniformly sized juvenile shrimp with an initial weight of 1.20 ± 0.03 g were randomly assigned to four groups, with each group consisting of six replicates of 25 shrimp each. Fish meal protein was replaced with 0%, 5%, 10%, and 15% pork meal, and crystalline amino acids and fish oil were supplemented accordingly. The groups were designated as P0, P5, P10, and P15, and the study duration was 70 days.ResultsResults indicated no significant difference in specific growth rate (SGR) between the P5 and P10 groups compared to the P0 group. However, the SGR in the P15 group was significantly lower than that in the P5 and P10 groups. Feed conversion rates (FCRs) for the P5 and P10 groups were comparable to the P0 group, whereas the P15 group showed a significantly higher FCR than the other groups. There were no significant differences in whole body composition among all the groups. Apart from alanine, the amino acid composition of muscles did not differ significantly among all the groups. Results of enzyme activity in plasma revealed that the replacement of fish meal with pork meal reduced levels of aspartate aminotransferase (AST) and superoxide dismutase (SOD). Specifically, levels of AST in the P5 and P15 groups were significantly lower compared to the P0 and P10 groups. Histological examination of midgut tissues showed that villus height initially increased and then decreased with higher replacement ratios. The P5 group had the highest villus height, while the P15 group had the lowest villus height. Analysis of gene expression related to liver immune functions indicated that genes in TLR signaling pathway were significantly elevated in the P15 group compared to the other groups.DiscussionIn conclusion, even with the supplementation of crystalline amino acids and fish oil, pork meal should not replace more than 10% of fish meal in the feed of P. monodon to maintain optimal growth and feed efficiency.

Multi-Omics Insights into Variety-Driven Differences in Rice Straw Feed Utilization: An In Vitro Fermentation Study

Multi-Omics Insights into Variety-Driven Differences in Rice Straw Feed Utilization: An In Vitro Fermentation Study

Effects of dietary protein levels with cottonseed protein concentrate inclusion on growth, feed utilization, liver health and intestinal microbiota of juvenile largemouth bass (Micropterus salmoides)

An 8-weeks growth trial was conducted to evaluate the effects of dietary protein levels mainly based on cottonseed protein concentrate (CPC) meal on growth performance, protein metabolism, liver health and intestinal microbiota of largemouth bass (Micropterus salmoides) juveniles. Five isolipidic (100 g/kg) diets were prepared with protein levels ranging from 400 to 560 g/kg, with CPC of 155 g/kg, 214 g/kg, 272 g/kg, 330 g/kg, 390 g/kg to obtain five experimental diets with gradient protein levels (399.9 g/kg, 428.0 g/kg, 462.8 g/kg, 503.5 g/kg and 541.5 g/kg, respectively (CPC1, CPC2, CPC3, CPC4 and CPC5)). 300 fish (initial body weight: 14.71 ± 0.50 g) were randomly assigned into 15 tanks (3 tanks per diet). The results showed that, the fish of CPC5 group had the highest specific growth rate (SGR), weight gain (WG) and feed efficiency (FE) (P < 0.05). Increased dietary protein up-regulated most liver key genes of mTOR pathway (akt, tor, s6k, 4ebp1, s6) while down-regulated atf4 at medium dietary protein (P < 0.05). The expression of fas was down-regulated with increased dietary protein, while dgat1 was higher at CPC5 group (P < 0.05). The genes related to lipolysis were up-regulated with increased dietary protein (P < 0.05). The key genes of apoptosis including bcl2, casp9, casp3 (apoptosis) oxidative stress and endoplasmic reticulum stress were significantly up-regulated at high dietary protein (P < 0.05), which reduced the antioxidant and anti-stress capacity of the liver. Dietary 462.8 g/kg protein could maintain the normal composition and metabolic function of intestinal microbiota. In summary, dietary protein requirement using CPC as main protein source was estimated to be 463 g/kg to 510 g/kg for liver health or best growth of largemouth bass juveniles.

Effects of Natural Carotenoid Source Enriched Feed on the Growth, Flesh Carotenoid, Composition, and Palatability of a Silver Barb (Barbonymus gonionotus)

Aim: The study compared the effects of different natural carotenoid-enriched feeds with a commercial carp feed on the growth, flesh carotenoid, composition, and palatability of Barbonymus gonionotus. Study Design: The study was conducted with four feeds treated as four treatments where, a commercial carp grower feed was used as control feed (CF) and three test feed were made by adding the powder of three carotenoid sources, viz., tomato (TMP), carrot (CRP), and beetroot (BRP) in the control feed at a rate of 2g/kg. Fifteen juveniles of B. gonionotus were stocked in each cage. The fish were fed with test feed twice a day at the rate of 5% (2.5% + 2.5%) of body weight and weighed fortnightly to adjust the ration size. Place and Duration of Study: The trial was conducted in twelve cages set in a pond at the Department of Fisheries, University of Rajshahi, Bangladesh, for 90 days. Methodology: At the end of the trial, the growth and feed utilization parameters, viz., weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), and protein efficiency ratio (PER), flesh carotenoid and composition, and palatability indicators of the fish were evaluated according to standard formulae, spectrophotometry, AOAC, and organoleptic sensory technique, respectively. Results: The higher WG (193.89±12.31 g) and SGR (1.41±0.08 %), better FCR (1.59±0.16) and PER (3.07±0.31), and higher carotenoids content (4.31±0.29 mg/g) were found in the fish fed with carrot-enriched feed, followed by the fish fed with tomato-enriched feed (WG: 174.86±11.50 g, SGR: 1.33±0.01 %, FCR: 1.74±0.04, PER: 2.78±0.06 and Carotenoids: 1.59±0.09 mg/g) and the beetroot-enriched feed (WG: 168.56±12.87 g, SGR: 1.30±0.08 %, FCR: 1.84±0.19, PER: 2.66±0.28 and carotenoids: 1.44±0.40 mg/g) when compared to the control fish. No significant difference in the flesh composition was found among the treatments. A significantly higher organoleptic sensory score (25.54±0.57) was recorded in the fish fed with carrot-enriched feed and lower in the control feed (19.52±0.77). Conclusion: The study concludes that 2g/kg carrot powder supplementation in feed is better for enhancing the growth, carotenoid deposition, and palatability of B. gonionotus.

Bacillus amyloliquefaciens SS1-fermented soybean meal influenced the flesh texture of Nile tilapia: Involvement of microbial metabolite propionate

Microbial fermentation is recognized to improve feed utilization and health of farmed animals. However, its effect on flesh quality and the underlying mechanisms remain understudied. Herein, Bacillus amyloliquefaciens SS1, a probiotic strain isolated from the intestinal tract of Nile tilapia (Oreochromis niloticus) was used to ferment soybean meal (FSM). Two tilapia experimental diets containing FSM and raw soybean meal were formulated for an eight-week feeding trial. Results showed that dietary FSM significantly increased the carcass ratio of fish, while there was no significant difference in weight gain or feed utilization between the two dietary treatments. Texture profile analysis showed that muscle springiness was improved by the FSM diet. There was no discernible difference in myofiber morphology between the two treatments. However, the FSM-fed fish had significantly lower muscle lipid contents than the control, accompanied by suppressed lipogenesis, while lipolysis was promoted both in muscle and liver tissues. Interestingly, the FSM diet modified gut microbial community, resulting in increased propionate concentrations. By establishing a high-fat model using primary hepatocytes of tilapia, we demonstrated the role of propionate in reducing lipid accumulation. Our finding highlights the emerging roles of gut-derived metabolites in affecting flesh quality by modifying host metabolism, providing a foundation for improving the flesh quality of aquaculture fish starting from the feed.

Nutritional Effect of Using a Bioactive Mixture (Lemon, Onion and Garlic) on Growth Performances, Feed Utilization, Immune Status and Gene Expression of Nile tilapia (Oreochromis niloticus)

Nutritional Effect of Using a Bioactive Mixture (Lemon, Onion and Garlic) on Growth Performances, Feed Utilization, Immune Status and Gene Expression of Nile tilapia (Oreochromis niloticus)

Impacts of winter crop choice and ewe body condition score change on whole farm profitability and production

Variations in body condition score (BCS) in ewes influences lamb survival, ewe survival and ewe lactation performance. Feeding a low protein diet such as fodder beet to ewes in mid-to-late pregnancy increases lamb losses and reduces lamb weaning weight even further. However, using high yielding forages such as fodder beet can reduce the area of winter crop required, introducing potential whole-farm benefits which may alter profitability. We analysed the effects of winter crop choice (brassica or fodder beet) and BCS (maintaining or reducing) on whole-farm production and profitability, using a targeted supplement to offset the impacts of fodder beet feeding. Eight farms were selected to represent low or high rainfall (590 and 1090 mm/annum respectively) regions of the South Island. Impacts of changing BCS on ewe and lamb survival at lambing, and lamb liveweight gain to weaning were calculated when fed either adequate (brassica) or low protein (fodder beet) diets in mid-to-late pregnancy. Production statistics and profitability were calculated using Farmax. Whole farm profitability was analysed using BCS change and winter forage crop as main treatments, blocked by low or high rainfall. Applying the effects of BCS and low protein diets on reproductive performance from prior published studies resulted in variation of 102 to 141 lambs weaned per 100 ewes mated, with the lowest value when the low protein, fodder beet only diet was used. Greatest number of lambs weaned was achieved when BCS was maintained through winter through provision of a balanced supplement, regardless of winter forage diet (P&lt;0.05). Lamb sale dates were later when fodder beet was used, due to lower lamb weaning weights, resulting in marginally higher prices due to changes in pricing schedule. Farm profitability was increased by 25% when BCS was maintained though winter (P&lt;0.05) irrespective of the diet used. Use of fodder beet must be accompanied by targeted supplementation to avoid ewe BCS loss increased lamb losses and the negative effects on wastage and animal welfare. Extra profitability could only be generated by opportunities to sell surplus feed during the summer. These responses were similar in both high and low rainfall environments. This study is unique in testing measured responses of BCS and targeted nutritional supplementation under specific physiological conditions on whole-farm profitability. Farmer decisions on feed utilisation and sale also have a significant influence on the potential to mitigate the effects of variations in winter forage choice.

Dietary vitamin E (α-tocopherol acetate) modulates growth, digestive enzymes, histopathology, and vulnerability of Nile tilapia, Oreochromis niloticus to Aeromonas hydrophila infection

Vitamin E is a fat-soluble vitamin that plays a vital function in several biological processes, and fish cannot synthesize it to meet their requirement. So, 56-day research was conducted to examine the influence of vitamin E (vit-E) (α-tocopherol acetate) on the Nile tilapia's growth, digestive enzymes, hematology, histology, and susceptibility to Aeromonas hydrophila. A total of 450 mono-sex Acclimated Nile tilapia (Oreochromis niloticus) were haphazardly dispersed into 30 aquaria, each with a capacity of 100 liters (15 fish/aquarium) to exemplify five groups with six replicates. A control diet (30 % protein) was enriched with 0.0 (E0), 150 (E150), 300 (E300), 600 (E600), and 1200 (E1200) mg/kg feed. Fish (13.5 ± 0.12 g) were given the trial diets until obvious satiation thrice daily for 56 days. At the end of the feeding trial, growth performance, digestive enzymes, hematology, and histology for the mid-intestine were examined. Subsequently, twenty fish from each treatment were challenged to contagion with Aeromonas hydrophila bacteria, and fish mortality was recorded for a further 14 days. At the end of the bacterial challenge, histology for the mid-intestine, liver, and spleen tissues was examined. Growth performance, feed utilization, and digestive enzyme secretion (proteases, lipase, and α-amylase) were substantially (P < 0.5) improved with raising vit-E levels in fish feeds up to E1200. Increasing the vit-E doses improved fish gut histomorphology by increasing the count and size of intestinal folds bordered by well-arranged enterocytes. The body composition was not influenced by dietary vitamin E, except lipid content, which increased substantially as vitamin E levels increased. Fish fed with vita-E enriched diets had higher resistance to A. hydrophila infection; however, the control group exhibited the greatest fish mortality rate (80 %), while the lowest rate was observed at E1200 (30 %). Hepatic and spleen tissues in the control group (E0) showed severe congestion and degeneration, whereas vit-E-treated fish groups progressively recovered normal histomorphology depending on the vit-E doses. Finally, this research recommends feeding Nile tilapia on vit-E, particularly 1200 mg/kg feed, to enhance its performance, welfare status, and resistance to A. hydrophila contagion.

Eubacterium siraeum suppresses fat deposition via decreasing the tyrosine-mediated PI3K/AKT signaling pathway in high-fat diet-induced obesity.

Obesity in humans can lead to chronic diseases such as diabetes and cardiovascular disease. Similarly, subcutaneous fat (SCF) in pigs affects feed utilization, and excessive SCF can reduce the feed efficiency of pigs. Therefore, identifying factors that suppress fat deposition is particularly important. Numerous studies have implicated the gut microbiome in pigs' fat deposition, but research into its suppression remains scarce. The Lulai black pig (LL) is a hybrid breed derived from the Laiwu pig (LW) and the Yorkshire pig, with lower levels of SCF compared to the LW. In this study, we focused on these breeds to identify microbiota that regulate fat deposition. The key questions were: Which microbial populations reduce fat in LL pigs compared to LW pigs, and what is the underlying regulatory mechanism? In this study, we identified four different microbial strains, Eubacterium siraeum, Treponema bryantii, Clostridium sp. CAG:413, and Jeotgalibaca dankookensis, prevalent in both LW and LL pigs. Blood metabolome analysis revealed 49 differential metabolites, including tanshinone IIA and royal jelly acid, known for their anti-adipogenic properties. E. siraeum was strongly correlated with these metabolites, and its genes and metabolites were enriched in pathways linked to fatty acid degradation, glycerophospholipid, and glycerolipid metabolism. In vivo mouse experiments confirmed that E. siraeum metabolites curb weight gain, reduce SCF adipocyte size, increase the number of brown adipocytes, and regulate leptin, IL-6, and insulin secretion. Finally, we found that one important pathway through which E. siraeum inhibits fat deposition is by suppressing the phosphorylation of key proteins in the PI3K/AKT signaling pathway through the reduction of tyrosine. We compared LW and LL pigs using fecal metagenomics, metabolomics, and blood metabolomics, identifying E. siraeum as a strain linked to fat deposition. Oral administration experiments in mice demonstrated that E. siraeum effectively inhibits fat accumulation, primarily through the suppression of the PI3K/AKT signaling pathway, a critical regulator of lipid metabolism. These findings provide a valuable theoretical basis for improving pork quality and offer insights relevant to the study of human obesity and related chronic metabolic diseases. Video Abstract.

Determination of the Impact of Extruded Soybean Press Cake on Rearing and Health Indices of Piglets

The study was conducted to evaluate the alternative to imported soybean meal—extruded soybean press cake—in feeding weaning pigs. The experiment was carried out with 20 35-day-old weaned pigs weighing about 8.8 kg, divided into 2 groups (10 pigs in each) differing in the main protein source: group I—control, solvent-extraction soybean meal, group II— extruded soybean press cake. The feed mixtures were iso-protein and iso-energetic. After 35 days of feeding, the pigs were slaughtered. The samples of blood, intestinal tissue and digesta, meat, and back fat were collected for analyses. Replacement of soybean meal with extruded soybean press cake in the weaners’ diet had no statistically significant effect on growth performance and feed utilization. Histomorphometry analysis of the intestines did not indicate any harmful changes. The soybean press cake did not affect the sum of volatile fatty acids in the large intestine, but the ammonia concentration was lower in the distal colon (p ≤ 0.05). It was found that the extruded soybean press cake in the feed significantly affected the fatty acid profile (p ≤ 0.05) of meat and back fat, increasing the amount of PUFAs; however, no negative impact on the durability of meat and back fat during storage was noted. In conclusion, the study confirmed the possibility of completely replacing solvent-extraction soybean meal with extruded soybean press cake in the feeding of weaned pigs.

Fermented Palm Kernel Cake Improves the Rumen Microbiota and Metabolome of Beef Cattle.

In this study, we utilised palm kernel cake as a substrate and fermented it with a composite of bacteria (Pediococcus pentosaceus CGMCC No. 27203 and Lactobacillus plantarum CGMCC No. 27202) and enzymes. We conducted a trial with twenty-four cattle, randomly divided into two groups of twelve cattle each. The control group (CON) was fed the standard farm diet, whereas the treatment group (PKC) received a diet with 3% of soyabean replaced by fermented palm kernel cake. The trial lasted for six weeks. The results showed no significant differences in growth performance between the PKC and CON groups. The abundance of Firmicutes, Bacteroidetes, Proteobacteria, and Spirochaetes was significantly higher in the PKC group than in the CON group. At the genus level, the abundances of Anaeroplasma, norank_f__Bacteroidales_UCG-001, norank_f__Absconditabacteriales_SR1, norank_f__p-251-o5, Prevotellaceae_NK3B31_group, Prevotellaceae_UCG-001, Prevotellaceae_UCG-004, and Treponema significantly increased in the PKC group. Lipid digestion and absorption pathways were significantly enriched in the PKC group. The results indicate that adding fermented palm kernel cake to the diet can increase the abundance of Bacteroidetes and Fibrobacteres in the rumen of beef cattle, enhancing the ability of the PKC group to degrade protein, carbohydrates, and fibrous materials in the feed, thereby improving the feed utilisation efficiency in beef cattle. Adding fermented palm kernel cake to the diet improved carbohydrate metabolism, metabolism of cofactors and vitamins, and nucleotide metabolism. Correlation analysis between the rumen microbiota and metabolic pathways showed that Prevotellaceae_UCG-001 and Prevotellaceae_UCG-003 were positively correlated with amino acid metabolism, Rikenellaceae_RC9_gut_group and Succiniclasticum were positively correlated with metabolism of cofactors and vitamins, and Prevotella and Ruminococcus were positively correlated with nucleotide metabolism. These findings elucidate the differences in rumen microbiota when fermented palm kernel cake is added to the diet, providing a theoretical basis for the application of fermented palm kernel cake in the diet of beef cattle.

Ruminant microbiome data are skewed and unFAIR, undermining their usefulness for sustainable production improvement

The ruminant microbiome plays a key role in the health, feed utilization and environmental impact of ruminant production systems. Microbiome research provides insights to reduce the environmental footprint and improve meat and milk production from ruminants. However, the microbiome composition depends on the ruminant species, habitat and diet, highlighting the importance of having a good representation of ruminant microbiomes in their local environment to translate research findings into beneficial approaches. This information is currently lacking. In this study, we examined the metadata of farmed ruminant microbiome studies to determine global representativeness and summarized information by ruminant species, geographic location, body site, and host information. We accessed data from the International Nucleotide Sequence Database Collaboration via the National Center for Biotechnology Information database. We retrieved 47,628 sample metadata, with cattle accounting for more than two-thirds of the samples. In contrast, goats, which have a similar global population to cattle, were underrepresented with less than 4% of the total samples. Most samples originated in Western Europe, North America, Australasia and China but countries with large ruminant populations in South America, Africa, Asia, and Eastern Europe were underrepresented. Microbiomes from the gastrointestinal tract were the most frequently studied, comprising about 87% of all samples. Additionally, the number of samples from other body sites such as the respiratory tract, milk, skin, reproductive tract, and fetal tissue, has markedly increased over the past decade. More than 40% of the samples lacked basic information and many were retrieved from generic taxonomic classifications where the ruminant species was manually recovered. The lack of basic information such as age, breed or sex can limit the reusability of the data for further analysis and follow-up studies. This requires correct taxonomic assignment of the ruminant host and basic metadata information using accepted ontologies adapted to host-associated microbiomes. Repositories should require this information as a condition of acceptance. The results of this survey highlight the need to encourage studies of the ruminant microbiome from underrepresented ruminant species and countries worldwide. This shortfall in information poses a challenge for the development of microbiome-based strategies to meet sustainability requirements, particularly in areas with expanding livestock production systems.

Effect of dietary supplementation of rubber seed kernel pellet on feed utilization, rumen fermentation, fatty acid profiles and health status in swamp buffalo.

Rubber seed kernel is a by-product of rubber cultivation and are high in oil and protein. This study was conducted to evaluate the effect of supplementing rubber seed kernel pellet (RUSKEP) on feed intake, nutrient digestibility, rumen fermentation, rumen fatty acid profiles, blood parameters, and immune response in swamp buffalo. Four male swamp buffalo with an initial body weight (BW) of 254 ± 10 kg and 26 months of age were used in this research. The experimental design was a 4  4 Latin squared design with RUSKEP supplementation at 0, 4, 6, and 8% of dry matter intake (DMI). Animals were fed concentrate at 1.0% BW, while rice straw was fed ad libitum. Supplementation with RUSKEP did not change DMI or nutrient digestibility (p>0.05), while ether extract (EE) digestibility increased cubically with the addition of RUSKEP (p<0.01). The ruminal pH, ammonia-nitrogen (NH3-N), and the proportion of acetate (C2) were similar among treatments (p>0.05). The proportion of propionate (C3) increased linearly (p≤0.04), leading to a decrease in the acetate to propionate ratio (C2:C3) (p≤0.04) with the addition of RUSKEP. Furthermore, the butyrate (C4) proportion decreased linearly with RUSKEP supplementation (p=0.03). The addition of RUSKEP did not affect on linoleic acid (LA; C18:2 cis-9,12 + trans-9,12), or α-linolenic acid (ALA; C18:3 cis-9,12,15) (p>0.05). With RUSKEP supplementation, the stearic acid (C18:0) content increased quadratically (p<0.01). The increasing level of RUSKEP was higher in cholesterol and eosinophils (p≤0.03). The immune function (IgA, IgM, and IgG) was similar among treatments (p>0.05). Supplementing RUSKEP with up to 8% of DMI could improve rumen fermentation efficiency without affecting feed utilization, rumen PUFA profile, or immune response in swamp buffalo.

Evaluating the Potential of Marine Algae as Sustainable Ingredients in Poultry Feed

Algae are a complex source of crucial nutrients, including proteins, minerals, vitamins, and carbohydrates. The use of marine algae, specifically Sargassum species, Gracilaria species, and Spirulina species, as feed ingredients in poultry feed was examined in the current research. This study’s aims were to carry out lipid profiling, proximate analysis, and heavy metal toxicity testing, as well as to evaluate the presence of hazardous hydrocarbons in the algae and investigate the effect of the fatty acid profile of Sargassum species on broilers. The proximate analysis was conducted on the algae types containing considerable quantities of fats and proteins and a sizable quantity of omega-3 fatty acids. This research assessed the productive effectiveness of broilers with 2.5%, 6%, and 10% algal additions in their diet. Fatty acid profiling of Sargassum species was performed at 1% and 2% levels in the bursa, fat pads, heart, liver, spleen, thymus, thighs, and breast. The findings showed no significant differences in the development performance or feed utilization efficiency of broilers with 2.5%, 6%, and 10% algae supplementation in their diet. The results of fatty acid profiling showed changes in the heart, liver, and spleen at 1% and 2% supplementations levels. However, this research concludes that if algae partially replaces the imported feed proteins used in animal feed, then these can achieve maximum beneficial effects on poultry health and performance. Algae are sustainable, easy to produce, and cost-effective sources of nutrients and contain numerous bioactive compounds, which will contribute to sustainability and food safety.

Growth performance, immunological, and biochemical responses of stinging catfish, (Heteropneustes fossilis) fingerlings reared in a biofloc-based production system

ABSTRACT A study was conducted to compare the high-density rearing of stinging catfish (Heteropneustes fossilis) fingerlings in both a control system and a biofloc system over 100 days. In the biofloc system, probiotics and a carbon source were added, while the control group had no additions. The biofloc system showed significantly (p < .05) higher floc volume (8.34 ± 1.33 ml L−1) and improvements in growth performance, survival rate, and biomass yield. Fingerlings reared in the biofloc system had increased digestive, oxidative enzyme activities and a lower feed conversion ratio. No changes were observed in the whole-body proximate composition between the groups. However, nonspecific immune responses, such as lysozyme and myeloperoxidase, were relatively improved, and other immune parameters like respiratory burst activity and total serum immunoglobulin were significantly increased in the biofloc system. In conclusion, biofloc-based rearing significantly enhanced the growth performance, feed utilization, and immunological conditions of stinging catfish.

Effects of spent substrate of oyster mushroom (Pleurotus ostreatus) on ruminal fermentation, microbial community and growth performance in Hu sheep.

The study aimed to evaluate the effects of Pleurotus Spent Mushroom Substrate (P.SMS) on the rumen microbiota, encompassing bacteria and fungi, as well as their interactions in Hu sheep. A total of forty-five 3-month-old Hu sheep were randomly assigned to five groups. Each group was fed diets in which whole-plant corn silage (WPCS) was substituted with P.SMS at varying levels: 0% (CON), 5% (PSMS5), 10% (PSMS10), 15% (PSMS15), or 20% (PSMS20). The results indicated that higher proportions of P.SMS during the experimental period might have a detrimental effect on feed utilization efficiency, kidney function, and blood oxygen-carrying capacity. Notably, moderate levels of P.SMS, specifically below 15%, were associated with improvements in rumen NH3-N levels and absorption capacity. The results indicated that (1) PSMS20 exhibited a significantly higher feed-to-gain ratio compared to CON (P < 0.05); (2) PSMS15 showed a significantly higher NH3-N content than CON, PSMS5, and PSMS20. Additionally, PSMS10 and PSMS20 had elevated concentrations of NH3-N compared to CON and PSMS5 (P < 0.05); (3) The length and width of rumen papillae were significantly greater in PSMS20 compared to CON and PSMS5 (P < 0.05); (4) Creatinine levels were significantly higher in PSMS20 than in CON, PSMS5, and PSMS10 (P < 0.05); (5) By the conclusion of the experiment, hemoglobin concentration in PSMS20 showed a significant increase compared to CON (P < 0.05). Furthermore, the addition of P.SMS influenced microorganisms at both the phylum and genus levels: (1) At the phylum level, the prevalence of Patescibacteria was significantly lower in PSMS20 compared to the other groups; (2) PSMS15 exhibited significantly higher relative abundances of Basidiomycota compared to CON and PSMS10, while PSMS20 also demonstrated significantly higher relative abundances compared to CON (P < 0.05); (3) At the genus level, the prevalence of Candidatus_Saccharimonas in PSMS20 was significantly lower than in PSMS5, PSMS10, and PSMS15. Conversely, the prevalence of Phanerochaete in PSMS15 was notably higher than in CON and PSMS10, and it was also significantly elevated in PSMS20 compared to CON (P < 0.05); (4) Correlation analysis indicated no significant correlation between changes in the structure of bacterial and fungal communities. Considering these findings, a high percentage of P.SMS negatively impacted feed utilization efficiency, blood oxygen carrying capacity, and kidney function, while a moderate percentage of P.SMS promotes rumen absorption capacity, indicating that feeding 10% P.SMS is optimal.

The Effect of Saccharomyces cerevisiae in Commercial Feed on Feed Utilization Efficiency, Growth Performance, and Blood Profile of Freshwater Pomfret (Colossoma macropomum) Fingerlings

The Effect of Saccharomyces cerevisiae in Commercial Feed on Feed Utilization Efficiency, Growth Performance, and Blood Profile of Freshwater Pomfret (Colossoma macropomum) Fingerlings

Effects of poultry by-product meal and complete replacement of fish oil with alternative oils on growth performance and gut health of rainbow trout (Oncorhynchus mykiss): a FEEDNETICS™ validation study

BackgroundAquaculture, traditionally a form of biotechnology, has evolved to integrate innovative biotechnological applications, such as advanced feed formulations, aimed at improving the growth performance and health of farmed fish species. In the present study, the effects of feeding rainbow trout with novel feed formulations were investigated. Fish growth, gut and liver morphology, the concentration of fatty acids in the fillet, and volatile fatty acids in the gut were assessed. The study also validated scenarios from in vivo experiments using a nutrient-based model called FEEDNETICS™. This globally used model serves as a tool for data interpretation and decision support in the context of precision fish farming.MethodsAlternative protein and oil sources, including poultry by-product meal (PBM) and natural algae oil, were explored as sustainable replacements for fishmeal (FM) and fish oil (FO). A 90-day feeding trial was conducted using rainbow trout, comparing two isoproteic, isolipidic and isoenergetic diets. The control diet contained 15% FM, 5% PBM, and 8% FO, while the test diet replaced FM with 15% PBM and 5% feather meal hydrolysate (FMH), and fully substituted FO with VeraMaris® natural algae oil and rapeseed oil.ResultsPBM successfully replaced FM protein without negatively affecting feed intake, growth performance or feed utilization in trout. The combination of PBM and natural algae oil was well tolerated by the trout and showed no negative effects on gut health. A detailed analysis of fatty acids in the fillet revealed that PUFAs of the n3 and n6 series were significantly higher in the PBM group than in the FM group. Values of fatty acid-related health indexes, including atherogenicity index, and thrombogenicity index, confirmed the high nutritional value of trout filet, thus representing a healthy product for human. In addition, the predictions using the FEEDNETICS™ indicated that the tested novel alternative formulations are economically viable. The validation of the model for fish growth resulted in a Mean Absolute Percentage Error (MAPE) of 8%.ConclusionsThe FEEDNETICS™ application enhances our ability to optimize feeding strategies and improve production efficiency in the aquaculture industry. VeraMaris® algae oil and PBM could serve as viable and sustainable raw materials for fish feed, promoting environmentally friendly aquaculture practices.

Effect of Dietary Benzoic Acid and Oregano Essential Oil as a Substitute for an Anti-Coccidial Agent on Growth Performance and Physiological and Immunological Responses in Broiler Chickens Challenged with Eimeria Species.

To overcome the antimicrobial residues in food, benzoic acid (BA) and oregano essential oil (OEO) are used in the broiler chicken industry. Independently, both exerted anticoccidial and antimicrobial actions and improved growth performance in broiler chickens. Their effect may be multiplied when they are used in combination. This present study was carried out to evaluate the efficacy of dietary BA and OEO alone or in combination as a substitute for a commercial coccidiostatic drug on growth performance and physiological and immunological responses in broiler chickens challenged with Eimeria species. A total of 252 unsexed 1-day-old broiler chicks were equally allotted to 36 pens, each pen containing seven chicks. The pens were randomly assigned to six treatments with six pens (replicates) for each treatment (n = 6)-(i) negative control, (ii) positive control, coccidia-challenged and non-treated, (iii) supplemented with salinomycin (an anti-coccidial drug) at 60 mg/kg of feed and coccidia-challenged, (iv) supplemented with BA at 500 mg/kg of feed and coccidia-challenged, (v) supplemented with OEOat 500 mg/kg of feed and coccidia-challenged (OEO), and (vi) supplemented with BA at 500 mg/kg of feed and OEO at 500 mg/kg of feed and coccidia-challenged (B&O). The liver enzymes and thyroxine and creatinine levels were not affected (p > 0.05) both in coccidia-challenged and supplemented chickens. The BA and OEO applied separately or in combination (B&O) significantly (p < 0.05) reduced gut pathogenic bacteria (Salmonella and Escherichia coli) and Eimeria spp., and concurrently enhanced (p > 0.05) the Lactobacillus population with better body weight gain, improved feed utilization, and superior hematological values. It also up-regulated (p > 0.05) the interferon-γ gene expression and down-regulated (p < 0.05) the interleukin-10 and Toll-like receptor-4 gene expression to protect the chickens from inflammatory reactions, which were not demonstrated in salinomycin-treated birds. The B&O supplementation increased (p < 0.05) the immune system by enhancing Eimeria-specific immunoglobulin Y titer and lymphocyte proliferation response. This study suggests that the combined application of OEO and BA can substitute for a commercial anti-coccidial agent (salinomycin) in controlling coccidiosis as well as improving growth performance, gut health, and immune responses in broiler chickens with a means of antimicrobial-resistant free food products.