Useful Source Of Protein Research Articles

Evaluation of black soldier fly larvae and protease supplementation of Lohmann Brown-lite laying hens performance and egg quality

Abstract Feed costs represent up to 60-70% of the total cost of poultry production, with protein sources being the most expensive feed component. Black soldier fly larvae meal (BSFLM) shows promise as a sustainable protein source for use in animal diets. This research was conducted to determine the effects of including up to 13% defatted BSFLM and a supplementary protease-based enzyme (Concentrase-P; CBS Bio Platforms, Inc., Calgary AB, Canada) on laying hen performance and egg quality. To test this objective, 180 Lohmann Brown-Lite hens (52 weeks of age) were fed experimental diets containing 0%, 6.5%, or 13% BSFLM, with or without Concentrase-P (3 × 2 factorial arrangement of treatments). The treatments were fed over 20 weeks. Results indicated reduced feed intake and body weight in laying hens fed a 13% dietary inclusion level of BSFLM (), while other performance traits (egg production and FCR) were similar among treatments () and met industry performance standards. Shell weight and egg breaking strength did not significantly change with the dietary inclusion level of BSFLM or enzyme inclusion (), although a significant decrease in egg weight and albumen height was noted (), as well as a significant decrease in albumen height for the Concentrase-P treatments (). Yolk colours were significantly lighter and redder in birds fed diets containing high levels of BSFLM (). Results support the use of BSFLM at dietary inclusion levels up to 13% in laying hen diets. Concentrase-P does not appear to be required in combination with BSFLM in terms of growth and laying performance, although potential benefits to other physiological factors are worth consideration.

Paecilomyces variotii (PEKILO®) in novel feeds for Atlantic salmon: Effects on pellet quality, growth performance, gut health, and nutrient digestibility and utilization

Filamentous fungi have potential as an alternative protein source for use in aquafeeds due to their high protein content and bioactive components. Paecilomyces variotii (PEKILO® mycoprotein) is a β-glucan- and nucleotide-rich filamentous fungi with a crude protein (CP) content of 60–70%. A 9-week feeding trial was conducted to evaluate the effects of P. variotii in diets for Atlantic salmon (initial average body weight of 24 g fish−1) reared in freshwater. Four experimental diets were formulated. Diet 1 was a control diet based on fish meal, soy protein concentrate, and wheat gluten meal. Diets 2, 3, and 4 were formulated so that P. variotii replaced 5, 10, and 20% of the CP content of the diets, respectively. Results showed that dietary inclusion of P. variotii was associated with changes in physical pellet quality, including significant linear (p < 0.0001) and/or quadratic (p < 0.01) decreases in pellet length, width, expansion, and durability. Conversely, significant linear (p < 0.0001) and quadratic (p < 0.025) increases in water activity, bulk density, and water stability index were associated with increasing replacement of the CP content of the diets with P. variotii. There were no significant differences in weight gain, growth rate or feed intake among fish fed the experimental diets (p > 0.05), but a significant linear improvement (p < 0.025) in feed conversion ratio (FCR) with increasing dietary inclusion of P. variotii was observed. The apparent digestibility coefficients for CP and gross energy of the experimental diets decreased linearly (p < 0.01) with increasing dietary levels of P. variotii. Similar results were observed for the essential and non-essential amino acids. Despite reduced digestibility, linear increases in nitrogen (p < 0.01), energy (p < 0.025), and mineral (p < 0.001) retention efficiencies were associated with increasing dietary levels of P. variotii. In the distal intestine, dietary inclusion of P. variotii resulted in significant (p < 0.05) upregulation of several cytokines (ifng, il10, and tgfb), effector molecules (inos, arg1, sod), and transcription factors (irf4), suggesting both activation and control of the inflammatory response in this key mucosa-associated lymphoid tissue. Overall, replacement of 20% of the CP content of the diet with P. variotii reduced digestibility of the experimental diets, but did not affect growth performance and improved FCR and nutrient utilization efficiency of salmon. Thus, P. variotii is a promising ingredient with potential for use in salmonid aquafeeds to improve fish performance and health.

Digestibility of corn distiller's dried grains with solubles (DDGS) in practical feeds with phytase and xylanase treatment fed to Nile Tilapia

AbstractObjectiveDistiller's dried grains with solubles (DDGS), a by‐product of ethanol production from cereal grains, has seen limited use by fish feed manufacturers as an alternative protein source. Over the past 20 years, advances and greater uniformity in processing methods have improved the quality of DDGS and, likely, its digestibility by fish. Our objective was to reevaluate the digestibility of corn DDGS by Nile Tilapia Oreochromis niloticus using a present‐day commercial product with and without xylanase and phytase enzyme treatment.MethodsApparent digestibility coefficients (ADCs) for the major proximate nutrients (dry matter, crude protein, crude fat, ash, digestible energy, and phosphorus) were determined using a practical, commercial‐type feed that was formulated and processed with DDGS supplied at 30% as weight : weight substitution (DDGS diet) of the reference diet (Ref diet). After drying, Ref and DDGS diets were top‐coated with phytase (3310 FTU/kg) + xylanase (7665 BXU/kg) enzymes (Ref+ and DDGS+) and compared with their untreated dietary counterparts.ResultDigestibility of crude protein was similar among diets and unaffected by enzyme treatment. For dry matter and digestible energy, ADC values were significantly lower for the DDGS diet, but enzyme addition improved digestibility to that of the Ref diets. Apparent digestibility for crude fat and ash was significantly better for the DDGS feed, with ash digestibility improved after treatment with xylanase + phytase for both Ref+ and DDGS+. For phosphorus, digestibility was similar among the Ref, Ref+, and DDGS diets, but with enzyme treatment, the phosphorus ADC increased significantly in DDGS+.ConclusionResults of this digestibility trial show that corn DDGS is a highly digestible protein source for use in feeds of Nile Tilapia at 30% of diet. Generally, apparent digestibility of proximate nutrients was either better or similar in DDGS when compared with the reference diet and could be further improved with the addition of xylanase + phytase.

High-pressure processing of beef increased the in vitro protein digestibility in an infant digestion model

Beef is an ideal protein source for use as a complementary food in infants. Considering the limited protein-digesting capacity of infants, it is required to enhance protein digestibility while minimizing the deterioration of beef quality. Thus, this study aimed to determine the effects of high-pressure processing (HPP) on the physicochemical properties and in vitro digestibility of beef proteins in an infant digestion model. HPP at 200 and 300 MPa decreased the tryptophan fluorescence intensity of the myosin and actin fractions relative to that at 0.1 MPa (P < 0.05). Compared to treatment at 0.1 and 100 MPa, HPP at 300 MPa decreased α-helix and β-turn contents in the myosin and actin fractions (P < 0.05), whilst increasing the β-sheet content (P < 0.05). Beef actomyosin content decreased (P < 0.05) during HPP at 200 and 300 MPa (c.f., 0.1 and 100 MPa). After in vitro digestion of beef, HPP at 200 and 300 MPa increased the α-amino group content and the abundance of proteins below 3 kDa in the digesta (P < 0.05). However, due to the considerable lipid oxidation at 300 MPa, HPP at 200 MPa is ideal for improving the protein digestibility of beef when incorporated into complementary foods for infants.

Potential of shrimp waste meal and insect exuviae as sustainable sources of chitin for fish feeds

Aquaculture is one of the world's fastest growing food-producing sectors, providing more than half of all fish consumed globally for human nutrition. However, to maintain such growth and meet the increasing demand for aquatic food, sustainable raw materials for fish feeds are needed. In this regard, insects represent one of the most promising alternatives to fish meal (FM) protein source for use in aquafeeds. In addition to protein, insects contain bioactive compounds, such as chitin, which is a natural polysaccharide abundantly present in the pupal exuviae of some insects. Studies have shown that dietary chitin or its derivate chitosan acts as a prebiotic thus modulating the gut microbial communities of fish. Accordingly, the present study aimed to evaluate the effect of two waste products rich in chitin, i.e., shrimp head meal (SHM), and insect (Hermetia illucens) pupal exuviae on the gut microbiota of rainbow trout (Oncorhynchus mykiss). Three isoproteic, isolipidic, and isoenergetic diets containing either FM, SHD, or a combination of FM and 1.6% of pupal exuviae meal (PEM) were tested through a 91-day feeding trial. At the end of the experiment, no differences in final mean body weight, specific growth rate, and feed conversion ratio values were observed between fish experimental groups. Mortality was <1% and it did not correlate with diet for the entire duration of the trial. However, a modulatory effect of dietary pupal exuviae on fish gut microbiota was detected. Indeed, gut bacterial species richness improved by including insect exuviae. In particular, Firmicutes and Actinobacteria phyla, mainly represented by Bacillus, Facklamia, Brevibacterium, and Corynebacterium genera, were enriched in trout receiving pupal exuviae. These genera are chitinolytic and short-chain fatty acids (SCFAs)-producing bacteria. SCFAs production was confirmed by gas chromatography analysis, which detected the highest amount of butyrate in feces of trout fed with pupal exuviae meal. Functional inference analysis of intestinal microbiota using PICRUST metagenome prediction tool, showed differences in response to diet. In particular, eleven pathways were significantly different between control fish (FM) and fish fed the PEM diet, whereas twenty functional traits were significantly different between the FM and SHM fish groups. Overall, our data confirmed that chitin from insect's pupal exuviae represents a promising functional ingredient, better than SHM, for positively modulating gut microbiota communities of rainbow trout.

Rapid quantification of cannabinoids in beef tissues and bodily fluids using direct-delivery electrospray ionization mass spectrometry

Hempseed cake is a byproduct of hempseed oil extraction and is potentially a useful source of protein and fiber for use in ruminant diets. However, data are lacking on the appearance and/or clearance of cannabinoids in tissues of animals fed hempseed cake. To this end, a rapid method for quantifying cannabinol (CBN), cannabidiol (CBD), cannabinolic acid (CBNA), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), cannabichromenic acid (CBCA), cannabidivarin (CBDV), cannabidivarinic acid (CBDVA), tetrahydrocannabinol (THC) and tetrahydrocannabinolic acid (THCA) in cattle tissues, plasma, and urine was developed using rapid screen electrospray ionization mass spectrometry (RS-ESI-MS). Regression coefficients of matrix-matched standard curves ranged from 0.9946 to >0.9999 and analyte recoveries averaged from 90.2 ± 15.5 to 108.7 ± 18.7% across all compounds. Limits of detection and quantification ranged from 0.05 to 2.79 ng · mL−1 and 0.17 to 9.30 ng · mL−1, respectively, while the inter-day relative standard deviation ranged from 5.1 to 15.1%. Rapid screening electrospray ionization mass spectrometry (RS-ESI-MS) returned no false positives for any cannabinoid in plasma, urine, and tissue (liver, skeletal muscle) samples from 6 non-dosed control animals (n = 90 samples; of which 72 samples were plasma or urine and 18 samples were tissues). Across-animal cannabinoid concentrations measured in 32 plasma samples of cattle dosed with ground hemp were quantified by RS-ESI-MS; analytical results correlated well (r 2 = 0.963) with independent LC-MS/MS analysis of the same samples.

The effect of egg white diet on phosphorus control in dialysis patients.

Nutritional interventions have been envisaged to improve hyperphosphatemia and malnutrition, two important risk factors associated with mortality in dialysis patients. We evaluated the effects of egg white consumption on serum phosphate and malnutrition in dialysis patients. In an open-label, per protocol clinical trial, conducted in Kerman dialysis centers, 150 hemodialysis patients aged ≥18 years with serum phosphorus ≥5.5 mg/dl were included in the study. All participants limited their intake of foods containing phosphorus for 4 weeks, and then they were divided into a control and an intervention group. The control group continued their ordinary diet and the participants in the intervention group consumed a Telavang egg white pack (containing six egg whites, 96 calories, 24 g protein) as a substitute for meat products 3 days a week for 8 weeks. Finally, changes in serum albumin, phosphorus, calcium, PTH, and cholesterol were measured. At the baseline, there were no significant differences in the laboratory variables between the two groups. After 8 weeks, serum cholesterol (124.3 ± 38.1, vs. 135.8 ± 28.8, p=0.003) and phosphorus levels (4.5 ± 1.03, vs. 6.7 ± 1.5, p=0.001) were significantly lower in the intervention group compared with the control group. Also, serum albumin (4.5 ± 0.07 vs. 3.7 ± 0.4, p=0.001) was significantly higher in the intervention group. Moreover, phosphorus, PTH, and cholesterol levels in the intervention group were significantly lower than their baseline values (p=0.001). The results showed that the egg white could be a useful source of protein for dialysis patients, as it simultaneously reduces serum phosphorus and cholesterol, and increases serum albumin.

Effect of Heating Time of Cottonseed Meal on Nutrient and Mineral Element Digestibility in Chicken (Based on Cottonseed Meal Replaced with All Soybean Meal).

Simple SummaryAt present, we are faced with the problem of a feed protein resource shortage. Cottonseed meal is a potential alternative protein source for use in poultry diets. High-temperature treatment is a common processing method of cottonseed meal. Our experiment was conducted to estimate the effects of heating time of cottonseed meal on nutrient digestibility and mineral element absorption of chicken.A digestibility test was conducted to estimate the effects of the heating time of cottonseed meal on nutrient digestibility and mineral element absorption in chicken. A total of 36, 45-week-old healthy New Yangzhou chickens with similar body weight were randomly divided into 6 groups with 6 replicates per group and one chicken per replicate. The chickens in Group A (control group) were fed the corn-soybean meal diet. The chickens in Groups B, C, D, E, and F (experimental groups) were fed the cottonseed meal to replace all soybean meal. The cottonseed meal in the experimental groups was treated with wet heating. The heating temperature was set at 120 °C, and the humidity was set at 50%. The heating time was set to 10, 15, 20, 25, and 30 min successively. The trial period was 4 day. The digestibility of crude protein, metabolic energy, and dry matter was highest using wet-heat treating for 15 min (p < 0.05). The digestibility of Fe increased significantly from 66.78% to 70.39% when the heating time of cottonseed meal was prolonged from 10 min to 30 min (p < 0.05). Compared with Group A, the digestibility of Zn was increased in Groups B and C, and then there was a decrease in Group D. Finally, the digestibility was increased again in Group F. The opposite pattern was shown in the digestibility of Cu and Zn. There was no significant effect of wet heat treatment time on the digestibility of calcium, phosphorus, and manganese (p > 0.05). When cottonseed meal is considered as feed for 45-week-old chickens, processing conditions of 120 °C and 50% humidity for 15 min are recommended.

Nutritional safety and suitability of a specific protein hydrolysate derived from whey protein concentrate and used in an infant and follow-on formula manufactured from hydrolysed protein by HIPP-Werk Georg Hipp OHG (dossier submitted by meyer.science GmbH).

The European Commission asked EFSA to deliver an opinion on the nutritional safety and suitability of a specific protein hydrolysate. It is derived from whey protein concentrate and used in infant and follow‐on formula by HIPP‐Werk Georg Hipp OHG. The dossier that was submitted to the European Commission aimed at requesting an amendment of Regulation (EU) 2016/127 with respect to the protein sources that may be used in infant and/or follow‐on formula. This opinion does not cover the assessment of the safety of the food enzymes used in the manufacture of the protein hydrolysate. The protein hydrolysate under evaluation is sufficiently characterised with respect to the fraction of the hydrolysed protein. In the pertinent intervention study provided, an infant formula manufactured from the protein hydrolysate with a protein content of 1.9 g/100 kcal and consumed as the sole source of nutrition by infants for 3 months led to growth equivalent to a formula manufactured from intact cow’s milk protein with the same protein content. No experimental data have been provided on the nutritional safety and suitability of this protein source in follow‐on formula. However, given that it is consumed with complementary foods and the protein source is considered nutritionally safe and suitable in an infant formula that is the sole source of nutrition of infants, the Panel considers that the protein hydrolysate is also a nutritionally safe and suitable protein source for use in follow‐on formula. The Panel concludes that the protein hydrolysate under evaluation is a nutritionally safe and suitable protein source for use in infant and follow‐on formula, as long as the formula in which it is used contains a minimum of 1.9 g/100 kcal protein and complies with the compositional criteria of Commission Delegated Regulation (EU) 2016/127 and the amino acid pattern in its Annex IIIA.

In Vitro Protein Digestibility of Selected Seaweeds.

Seaweed biomass is considered a valuable and potential, alternative protein source but it is currently under-exploited. Seaweed or Macroalgae do not require arable land and freshwater for their cultivation, they are fast growing and contain several health ingredients and beneficial macronutrients. In this study, we determined the in vitro k-Protein Digestibility-Corrected Amino Acid Score (k-PDCAAS) values of six different, Irish seaweeds using the rapid k-PDCAAS method. Based on the amino acid profile and protein content of each seaweed, the in vitro protein digestibility and k-PDCAAS scores were calculated. In addition, the limiting amino acid(s) for each of the six seaweeds was/were determined. Results suggest that although the in vitro digestibility was quite similar for all analyzed seaweeds, their k-PDCAAS scores varied significantly. The red seaweed Palmaria palmata had a k-PDCAAS score of 0.69 ± 0.014, while Fucus serratus had a value of 0.63 ± 0.084 and Alaria esculenta a value of 0.59 ± 0.021. The seaweeds were found to be rich in essential amino acids and taurine. Overall, the amino acid composition of the seaweeds studied suggests that they are suitable alternative protein sources for use in human nutrition providing both essential and non-essential amino acids to the consumer.

Single cell production by Claveromycice frajilice and Fusarium oxysporum in Kilka stick water

The production of single cell protein (SCP) is one of the cheap protein sources for use in aquaculture. In this study, Claveromycice frajilice and Fusarium oxysporum were used to produce SCP using Kilka stick water as the source of medium. Adaptation of C. frajilice and F. oxysporum to pure stick water was performed by increasing the concentration of stick water in distilled water. Treatments included 50% and 100% stick water, and a group without stick water as control. The pattern of the yeast and fungus growth was studied by spectrophotometry at 600 nm. The final product was analyzed for values of dry materials, amino acids profiles, total protein, moisture and ash. The results showed protein production by C. frajilice in 50% and 100% stick water was 55.35% and 57.47%, respectively, compared to 54.65% in control group (P>0.05). Protein production using F. oxysporum was 53.17% and 54.39±0.45% in 50% and 100% stick water, respectively compared to 49.71% in control group (P>0.05). The results showed that amino acids composition in produced SCP was comparable with the suggested profiles of requirement by FAO/WHO and NRC. Based on to the obtained results, application of pure Kilka stick water is suitable for production of C. frajilice as the source of SCP.

The effect of Kapok (Ceiba pentandra) (Linn] [Gaertn] meal on sperm production rate, gonadal and extragonadal sperm reserves in male rabbits

Twenty grower male rabbits of mixed breeds were used to evaluate the effect of Kapok seed meal on sperm production and sperm storage capacity: Five bucks each were randomly assigned to each of four isocaloric and isonitrogenous diets containing decorticated Kapok seed meal at 0), 10, 15 und 20% levels. After 8 weeks of ad libitum feeding, four bucks per treatment were randomly selected from each treatment group, sacrificed and their testes evaluated for sperm production, the efficiency of spermatogenesis and sperm storage capacity. The results did not show any significant differences (P&gt;0.05) between the treatments in Daily sperm production (DSP), Daily sperm production/ gram testis (DSP/g) as well as in gonadal and extragonadal sperm reserves. These results suggest that decorticated Kapok seed meal had no significant effect on sperm production in breeding bucks at an inclusion level of up to 20%. KSM may thus be a useful source of protein for rabbit bucks.

Kidney bean protein products as potential antioxidative and antihypertensive alternatives for non-pharmacological inhibition of angiotensin-converting enzymes

Kidney bean protein (KBP) albumin (KBPA) and globulin (KBPG) were produced by salt extraction method while the isolate (KBPI) was prepared by alkaline extraction followed by isoelectric precipitation. Furthermore, enzymatic hydrolysates of KBPI were prepared by treatment with alcalase (KBPH-A) and pepsin+pancreatin (KBPH-PP) respectively, while the antioxidant and angiotensin-converting enzyme (ACE) inhibiting activities of KBP products were evaluated after determining their amino acid (AA) composition profile. The result of the AA profile showed that while the hydrophobic amino acid (HAA) of KBPG (41%) was higher than KBPA (39%) and KBPI (36%) respectively, they however had similar (11%) aromatic amino acids (AAA). In addition, enzymatic hydrolysis resulted in increased contents of HAA and AAA of KBPH-A and KBPH-PP (42–45%; 14%), respectively. The KBPG had the highest OH− and ABTS− scavenging activities (40 and 45%) among the non-hydrolyzed fractions, which increased (70 and 75%) after hydrolysis by alcalase and PP. The KBPG had higher bioactivities (antioxidant and ACE inhibition) than the KBPA, which might be due to more hydrophobic character resulting from the higher disulfide bond present in globulin compared to the glycoprotein albumin. The hydrolyzed proteins had significantly higher (p<0.05) DPPH scavenging, metal chelation and ferric reducing activities than the non-hydrolyzed KBP. The ACE-inhibitory ability of KBP products was positively related to their AA profile, suggestive of the role of hydrophobicity, strong disulfide bonds and hydrolysis during inhibition. The increased ACE inhibitions by KBPH-PP (93%) compared to KBPH-A (85%) confirmed the effectiveness of dual endo- and exo-peptidase activities of PP over single endo-peptidase alcalase. This study presents valuable information on the production of potential compounds (protein hydrolysates) from an edible plant protein source for use in the management of cardiovascular diseases.

Nutritional safety and suitability of a specific protein hydrolysate derived from whey protein concentrate and used in an infant and follow-on formula manufactured from hydrolysed protein by Danone Trading ELN B.V.

The European Commission asked EFSA to deliver an opinion on the nutritional safety and suitability of a specific protein hydrolysate. It is derived from whey protein concentrate and used in an infant and follow‐on formula by Danone Trading ELN B.V, which submitted a dossier to the European Commission to request an amendment of Regulation (EU) 2016/127 with respect to the protein sources that may be used in the manufacture of infant and/or follow‐on formula. This opinion does not cover the assessment of the safety of the food enzymes used in the manufacture of the protein hydrolysate. The protein hydrolysate under evaluation is sufficiently characterised with respect to the fraction of the hydrolysed protein. In the pertinent intervention study provided, an infant formula manufactured from the protein hydrolysate with a protein content of 2.3 g/100 kcal and consumed as the sole source of nutrition by infants for 3.5 months led to growth equivalent to a formula manufactured from intact cow's milk protein (2 g protein/100 kcal). No experimental data have been provided on the nutritional safety and suitability of this protein source in follow‐on formula. However, given that it is consumed with complementary foods and the protein source is considered nutritionally safe and suitable in an infant formula that is the sole source of nutrition of infants, the Panel considers that the protein hydrolysate is also a nutritionally safe and suitable protein source for use in follow‐on formula. The Panel concludes that the protein hydrolysate under evaluation is a nutritionally safe and suitable protein source for use in infant and follow‐on formula, as long as the formula in which it is used contains a minimum of 2.3 g/100 kcal protein and complies with the compositional criteria of Commission Delegated Regulation (EU) 2016/127 and the amino acid pattern in its Annex IIIA.

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 suitable and cost-effective alternative protein sources for use in commercial fish diets will be the most critical factor in the development of intensive aquaculture. Insect meals are nutritious and healthy alternatives to fishmeal because of its rich nutritional values especially protein, fat and minerals. Housefly maggot (Musca domestica) meal is also rich in B complex vitamins, trace elements and phosphorus. From the results of previous studies, Housefly maggot meal can be successfully used to replace fishmeal portion partially or completely in the fish diets. Also, the results observed that not physiological stressful was introduced in the fish by feeding Housefly maggot 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 performance of fish that fed diets containing maggot meal over those solely fed on fishmeal diets. This is a reflection of the nutritional quality and acceptance of this biomaterial.

Intestinal Transcriptome Analysis Highlights Key Differentially Expressed Genes Involved in Nutrient Metabolism and Digestion in Yellowtail Kingfish (Seriola lalandi) Fed Terrestrial Animal and Plant Proteins.

This study investigated the effects of dietary terrestrial animal and plant proteins on the intestinal transcriptomes of yellowtail kingfish (YTK), Seriola lalandi, an ecologically and economically important marine species in Australia. Five diets containing fish meal (FM), poultry by-product meal (PBM), blood meal (BLM), faba bean meal (FBM) and corn gluten meal (CGM) were formulated and fed over a period of 4 weeks. The Illumina RNA-sequencing (RNA-Seq) results identified a suite of differentially expressed genes involved in nutrient metabolism and protein digestion pathways, reinforced by quantitative polymerase chain reaction (qPCR) results. These findings provide molecular support to the notion that PBM and FBM are useful raw materials in commercial diets for YTK. Using the same evidence, we have demonstrated that BLM and CGM may be less useful and their incorporation into commercial aquafeeds for this species should be done cautiously. The differentially expressed genes showed a subtle difference and high correlation with apparent nutrient digestibility of raw materials. Further, our results indicate that transcriptome profiling provides a useful tool to evaluate alternative protein sources for use in aquaculture feeds.

Nutritional evaluation of seal by-products as an alternative protein source for use in monogastric animals

Seal by-products (grey seal with the bone in, grey seal with the bone removed, and harp seal) were subjected to five different processing methods: high (100 °C) and low (45 °C) temperature oven-drying, freeze-drying (FD), silage by acid or natural fermentation. Growth performance of diets containing these seal by-products was evaluated in rats as a monogastric model species. With the exception of naturally fermented grey seal without bone, weight gains for rats fed the boneless grey seal products were highest of the seal products (24.65–30.04 g rat−1) and statistically similar to those of rats fed casein (32.15 g rat−1). An in vivo crude protein (CP) digestibility study was conducted using 12 adult white rats in metabolic cages that allowed separate collection of urine and feces. The 16% CP diets contained chromic oxide as an inert fecal marker at 0.5%. Total fecal and urine production, as well as feed and water intake, were recorded daily within the three experimental periods. Digestibility of CP was significantly higher for the naturally fermented grey seal without bone silage (94.0%) than casein (89.0%), whereas the other seal products were statistically similar (91.7%–92.7%). The CP content of FD grey seal was as high as 91.7% (FD). Seal by-products have the potential to be used as alternative high-protein feedstuffs in monogastric diets.

Characterization of plant-based protein sources for use in canine and feline nutrition

The objective of this study was to determine the macronutrient composition and standardized amino acid digestibility of 14 novel, plant-based, protein sources. The 14 protein sources are comprised of protein concentrates (pea, potato, faba bean, yeast, and soy concentrates), pulses (garbanzo beans, navy beans, black beans, lentils, and peas), and byproducts (corn gluten meal, peanut flour, soybean meal, and soy flakes). Macronutrient compositions and a complete amino acid profile were analyzed for all 14 protein sources. Cecectomized roosters (n=4/treatment) were utilized in a precision-fed rooster assay to measure standardized amino acid digestibility and true metabolizable energy corrected for nitrogen (TMEn). The roosters were precision-fed 30g of a 1:1 ratio of an ingredient and corn mixture. Excreta was collected after 48h, freeze-dried, and analyzed for a complete amino acid profile. Due to the high amino acid digestibility and well-balanced essential amino acid profiles, these plant-based proteins have the potential to become viable protein sources in canine and feline diets.

Next generation sequencing for gut microbiome characterization in rainbow trout (Oncorhynchus mykiss) fed animal by-product meals as an alternative to fishmeal protein sources.

Animal by-product meals from the rendering industry could provide a sustainable and commercially viable alternative to fishmeal (FM) in aquaculture, as they are rich in most essential amino acids and contain important amounts of water-soluble proteins that improve feed digestibility and palatability. Among them, poultry by-product meal (PBM) have given encouraging results in rainbow trout (Oncorhynchus mykiss). However, the introduction of new ingredients in the diet needs to be carefully evaluated since diet is one of the main factors affecting the gut microbiota, which is a complex community that contributes to host metabolism, nutrition, growth, and disease resistance. Accordingly, we investigated the effects of partial replacement of dietary FM with a mix of animal by-product meals and plant proteins on intestinal microbiota composition of rainbow trout in relation to growth and feeding efficiency parameters. We used 1540 trout with an initial mean body weight of 94.6 ± 14.2 g. Fish were fed for 12 weeks with 7 different feed formulations. The growth data showed that trout fed on diets rich in animal by-product meals grew as well as fish fed on control diet, which was rich in FM (37.3%) and PBM-free. High-throughput 16S rRNA gene amplicon sequencing (MiSeq platform, Illumina) was utilised to study the gut microbial community profile. After discarding Cyanobacteria (class Chloroplast) and mitochondria reads a total of 2,701,274 of reads taxonomically classified, corresponding to a mean of 96,474 ± 68,056 reads per sample, were obtained. Five thousand three hundred ninety-nine operational taxonomic units (OTUs) were identified, which predominantly mapped to the phyla of Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria. The ratio between vegetable and animal proteins proved to play a central role in determining microbiome profiles and Firmicutes and Proteobacteria phyla were particularly discriminatory for diet type in trout. Plant ingredients favoured a higher Firmicutes:Proteobacteria ratio than animal proteins. Acceptable abundance of Firmicutes was guaranteed by including at least 25% of vegetable proteins in the diet regardless of animal protein source and percentage. In summary animal by-product meals, as replacements to FM, gave good results in terms of growth performances and did not induce significant changes in gut microbial richness, thus proving to be a suitable protein source for use in rainbow trout aqua feed.

Digestibility and nitrogen balance of pig diets containing gradually increasing levels of rapeseed meal

Rapeseed meal (RSM), a by-product of extracted rapeseed oil production, is a potential protein source for use in pig diets. To determine the best levels of RSM inclusion in diets of fattening pigs as well as the digestibility and energy value of diets containing gradually increasing levels of RSM, a digestibility trial was conducted. The trial was performed according to a 4x4 Latin square experimental design, with 4 Large White x Landrace castrated male pigs weighing on average 47.3kg. The animals were housed in metabolism cages during the whole period the duration of which was a total of 66 days. The experiment was divided into 5 periods, an adjustment period and 4 experimental periods, during which pigs consumed 4 experimental diets. The diet C (control) was a basal diet based on corn and soybean meal, while the other experimental diets included RSM at levels 90 (low- L), 180 (medium- M) and 270 (high- H) g.kg-1 of feed, respectively. Each experimental period consisted of 10 preliminary days during which the animals were adapted to the diets, followed by a 4 days period for collection of faeces, urine and feed refusal. The gradual increase in the level of RSM in the experimental diets resulted in a significant (P&lt;0.05) reduction in the apparent digestibility of CP, but only for the diet with the highest level of RSM, compared to the control diet and this one with the lowest level of RSM . Any increase in the level of RSM in the experimental diets resulted in significant (P&lt;0.05) increase on the apparent digestibility coefficient (ADC) of CF and very significant (P&lt;0.01) increase in diets M and H, compared to the control and diet L. Similar were the effects of RSM levels in the diets on the apparent digestibility coefficient of NDF, ADF and cellulose. As conclusion, the gradual increase in the level of RSM in the fattening pigs’ diets did not significantly affect ADC of DM and gross energy, caused a significant reduction in the ADC of CP, and a significant improvement in the ADC of CF as well.