Feather meal processing methods impact the production parameters, blood biochemical indices, gut function, and hepatic enzyme activity in broilers.

This study investigated the effects of feather meal (FM) processing methods on production parameters, blood biochemical indices, intestinal morphology, digestive and hepatic enzyme activities, and gastrointestinal tract pH and microflora of broilers. A total of 480-d-old male broilers were used for 42 d in a completely randomized design with eight treatments and five replicates (12 chicks/replicate). Treatments were 1) a control diet (without FM), 2) a diet containing 4% raw FM (RFM), 3) a diet containing 4% processed FM (PFM) by autoclave (Au-PFM), 4) a diet containing 4% fermented FM (FFM) by Bacillus licheniformis (Bl-FFM), 5) a diet containing 4% FFM by Bacillus subtilis (Bs-FFM), 6) a diet containing 4% FFM by Aspergillus niger (An-FFM), 7) a diet containing 4% FFM by B. licheniformis + B. subtilis + A. niger (Co-FFM), and 8) a diet containing 4% PFM by an enzyme (En-PFM). Results showed that in the FFMs the contents of ash, ether extract, total volatile nitrogen, and amino acids including Lys, Met, Thr, Trp, His, Leu, Gly, Ile, Phe, and Tyr increased (P < 0.05), while crude fiber, crude protein, and dry matter content decreased (P < 0.05). Compared with the control, the Co-FFM diet had no significant differences (P > 0.05) in total body weight gain (2,827 vs. 2,791 g/chick), total feed intake (5,018 vs. 4,991 g/chick), European production efficiency factor (375 vs. 377), European Broiler Index (371 vs. 371), and feed conversion ratio (1.77 vs. 1.78 g/g). Feeding FFM decreased (P < 0.05) serum total cholesterol (1.46-fold), triglyceride (1.61-fold), very low-density lipoprotein cholesterol (1.61-fold), and low-density lipoprotein cholesterol (2.27-fold) compared to the control. Also, FFM increased (P < 0.05) villus height (1,045 to 1,351, 661 to 854, and 523 to 620 µm), and villus height to crypt depth ratio (6.15 to 8.45, 4.55 to 7.04, and 4.27 to 5.45), in the duodenum, jejunum, and ileum, respectively, compared to the control. Compared to the control, the Co-FFM diet increased (P < 0.05) protease (34, 39, and 45 %) in the pancreas, duodenum, and jejunum, as well as amylase (73, and 97 %) activities in the duodenum, and jejunum, respectively. Diets containing FFM reduced (P < 0.05) pH in the crop, gizzard, and ileum, and decreased (P < 0.05) Escherichia coli (6.12 to 5.70) count in ileum compared to the control. The Co-FFM diet increased (P < 0.05) lactic acid bacteria count in crop (6.77 to 7.50) and ileum (6.94 to 7.73), also decreased (P < 0.05) coliforms (6.31 to 5.75) count in ileum compared to the control. In conclusion, FM fermentation, particularly Co-FFM, improves the nutritional value of FM, converting it into a decent source of dietary protein for broilers.

Fermentation represents an attractive alternative method for feather meal (FM) efficient bioconversion and its nutritional value enhancement. This study investigated the effects of FM processing methods on broilers. Experimental diets were 1) a control diet (without FM), 2) a diet containing 4% raw FM (RFM), 3) a diet containing 4% processed FM (PFM) by autoclave (Au-PFM), 4) a diet containing 4% fermented FM (FFM) by Bacillus licheniformis (Bl-FFM), 5) a diet containing 4% FFM by Bacillus subtilis (Bs-FFM), 6) a diet containing 4% FFM by Aspergillus niger (An-FFM), 7) a diet containing 4% FFM by B. licheniformis + B. subtilis + A. niger (Co-FFM), and 8) a diet containing 4% PFM by an enzyme (En-PFM). Results showed that FFMs increased the contents of ash, ether extract, total volatile nitrogen, and amino acids including Lys, Met, Thr, Trp, His, Leu, Gly, Ile, Phe, and Tyr, while decreased crude fiber, crude protein, and dry matter content. The production parameters of birds fed Co-FFM were similar to the control group. In addition, FFMs decreased serum total cholesterol (1.46-fold), triglyceride (1.61-fold), very low-density lipoprotein cholesterol (1.61-fold), and low-density lipoprotein cholesterol (2.27-fold). Furthermore, Co-FFM improved intestinal morphology, enzyme activities, and beneficial bacterial populations. In conclusion, Co-FFM, improves the nutritional value of FM, converting it into a decent source of dietary protein for broilers.

Lethality Validation for Human Pathogenic Salmonella enterica on Chicken Feathers and Blood during Simulated Commercial Low-Temperature Dry Rendering.

Poultry rendering is the process of upcycling inedible poultry carcass materials into useful animal food/feed components as well as other valuable commercial products. Microbiological safety validation is nonetheless critical to ensuring the prevention of food safety hazard(s) transmission. This study determined the death kinetics of the thermotolerant Salmonella enterica serovar Senftenberg isolate 775W in chicken feathers and blood in low-temperature dry rendering (i.e., no direct contact with heating medium) to validate pathogen inactivation in commercial processing. Chicken feathers and blood were inoculated with Salmonella Senftenberg 775W and heated to 60, 70, or 80 °C for up to 60, 20, and 5 min, respectively. Three identically completed replicates (N = 3) for each product were conducted. Pathogen inactivation data were fitted to a non-linear model, providing for the detection and characterization of shoulder, log-linear death, and tailing components in death curves. The analysis showed a >7-log10 reduction in Salmonella was achieved across all processing temperatures, with t7D values (time for 7.0 log-cycle lethality) ranging from 21.68, 7.30, and 4.26 min for feathers and 18.38, 5.03, and 2.79 min in blood at 60, 70, and 80 °C, respectively. Study findings validate that low-temperature processing conditions can inactivate Salmonella in poultry-rendered offal.

Valorization of chick feather wastes by Geobacillus thermodenitrificans PS41 to enhance the growth of Vigna unguiculata plant and Cyprinus carpio fish.

Chicken feather meal has had a significant biofertilizer approach in recent years. The current study aims to assess feather biodegradation to promote plant and fish growth. The Geobacillus thermodenitrificans PS41 strain was more efficient in feather degradation. Feather residues were separated after degradation and evaluated under a scanning electron microscope (SEM) to detect bacterial colonization on feather degradation. It was observed that the rachi and barbules were entirely degraded. The complete degradation by PS41 suggests a relatively more efficient feather degradation strain. According to Fourier-transform infrared spectroscopy (FT-IR) studies, PS41 biodegraded feathers contain the functional groups of aromatic, amine, and nitro compounds. The present study suggested that biologically degraded feather meal improved plant growth. The feather meal combined with nitrogen-fixing bacterial strain showed the highest efficiency. The biologically degraded feather meal and Rhizobium combination induced physical and chemical changes in the soil. It is directly involved in soil amelioration, plant growth substance, and soil fertility, enhancing a healthy crop environment. The feather meal 4 and 5% was used as a feed diet of common carp (Cyprinus carpio) to increase growth performances and feed utilization parameters. In hematological and histological studies of formulated diets, significantly no toxic effects occurred in fish blood, gut, or fimbriae.

Valorization of feather waste in Brazil: structure, methods of extraction, and applications of feather keratin.

This systematic review presents the potential of using feather waste as a ß-keratin source, including the Brazilian scenario in the generation of this byproduct. The structure and properties of α- and ß-keratin, the methods commonly reported to extract keratin from poultry feathers, and applications of feather keratin-based materials are also covered in this review. The literature search for poultry production data in Brazil was conducted for the last 2 years, for the period 2021-2022. A broad literature search for extraction methods and applications of feather keratin was done for the period 2001-2022. The poultry industry is one of the largest sectors of the food industry, and Brazil was the third-largest world producer of chicken meat with more than six billion chickens slaughtered in 2021. Poultry feathers constitute about 7% weight of broilers; thus, it can be estimated that about one million tons of poultry feathers were generated in Brazil in 2021, and the improper disposal of this byproduct contributes to environmental problems and disease transmission. The most common method of reusing feathers is the production of feather meal. From economic and environmental points of view, it is advantageous to develop processes to add value to this byproduct, including the extraction of keratin. Among natural biodegradable polymers, keratin-based materials have revolutionized the field of biomaterials due to their biocompatibility and biodegradability, allowing their application in biomedical, pharmaceutical, chemical, and engineering areas.

Polycyclic Aromatic Hydrocarbons (PAHs) and Metals in Diverse Biochar Products: Effect of Feedstock Type and Pyrolysis Temperature.

Biochar's agricultural and environmental benefits have been widely demonstrated; however, it may cause environmental contamination if it contains large amounts of pollutants such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). Therefore, this study aimed to assess the contents of PAHs and HM in a range of biochars generated from different sources and pyrolysis temperatures. A range of feedstock was converted to biochar, including sewage sludge (SS), olive mill pomace (OP), feather meal (FM), soft offal meal (CSM), chicken manure (CM), and date palm residues (DPR). Each feedstock was then pyrolyzed at three temperatures of 300, 500, or 700 °C, thereby producing a total of 18 types of biochar. These biochar products were analyzed for 16 PAHs and eight metals (Cr, Mn, Fe, Ni, Cu, Zn, Cd, and Pb). Benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo(a)pyrene were significantly greater in the biochar produced at 700 °C than in that produced at 300 °C, especially for CM. The concentrations of dibenz(a,h)anthracene were significantly lower at 700 °C but greater at 500 °C and 300 °C in DPR. Increasing the pyrolysis temperature from 300 to 700 °C significantly increased the concentrations of metals, including Cr in SS and OP; Mn in CM; and Fe, Ni, Cu, and Zn in SS. However, the concentration of Cd was significantly lower in the SS when biochar was produced at 700 °C than at 500 or 300 °C. The type of feedstock used and the pyrolysis temperature are key factors influencing the contents of PAHs and HMs in biochar, both of which need to be considered during the production and use of biochar. Further investigations are recommended to establish the relationships between pyrolysis temperature and types of feedstock and the formation of PAH or the concentrations of metals. Monitoring the concentrations of PAHs and HMs before applying biochar to soil is also recommended.

Bacillus amyloliquefaciens CU33 fermented feather meal-soybean meal product improves the intestinal morphology to promote the growth performance of broilers.

This study is aimed to select optimum keratin degradation ability from Bacillus strains for feather meal-soybean meal fermentation, and favorably water content for the strain during fermentation of feather meal-soybean meal, and finally investigate the effects of the fermented feather meal-soybean meal product (FFSMP) on growth performance, carcass trait, clinical blood biochemistry, and intestinal morphology of broilers. Thirty-six bacteria strains from soil, sewage pool, and feather waste were screened and selected Bacillus subtilis var. natto N21 (N21), B. subtilis CU14 (CU14), and B. amyloliquefaciens CU33 (CU33) with better keratinase activity and feather-degrading rate. The result of trial 1 showed that the FFSMP produced by CU33 had the optimum physiochemical characterizations, amino acid composition and feeding performance for broilers. Hence the effects of water content (45, 50, 55, and 60%) on FFMSP fermentation of CU33 were investigated in trial 2. Result showed that pH value, counts of Bacillus-like bacteria, γ-PGA, viscosity, surfactin yield and odor all significantly increased according to the water content (P < 0.05). The protease activity reached significantly highest in the 55% and 60% water content groups (P < 0.01). The broilers performance of 55% and 60% water content group were significantly higher than control group (P < 0.05) in weight gain (WG), feed intake (b) at 0 to 21-d-old and the WG, feed conversion ratio (FCR), and production efficiency factor at 0 to 35-d-old, and could reach the similar growth performance as fish meal group (P > 0.05). The fermentation groups significantly decreased urea nitrogen (P < 0.05) and increased creatinine (P < 0.05) in the blood. The fermentation groups also significantly decreased the crypt depth in the duodenum (P < 0.05) and increased villus height to crypt depth ratio of the duodenum (P < 0.05). In conclusion, CU33 shows the best degradation rate for feather and keratinase activity, and the FFSMP with a water content of 50% to 60% during fermentation is suggested. Diets supplemented with 5% FFSMP can promote the growth of broilers by improving the morphology of the duodenum and achieve the feeding effect of high-quality fish meal.

Effects of dual-frequency slit ultrasound on the enzymolysis of high-concentration hydrolyzed feather meal: Biological activities and structural characteristics of hydrolysates.

Ultrasound-assisted enzymolysis has been applied to improve conventional enzymolysis, while there are rare reports on the application of ultrasound to high-concentration feather protein enzymolysis. Therefore, the feasibility of dual-frequency slit ultrasound (DFSU) for enzymolysis of high-concentration hydrolyzed feather meal (HFM), as well as the biological activities and structural characteristics of hydrolysates were investigated. The single-factor test was used to optimize the ultrasonic processing parameters: substrate concentration, frequency mode, intermittent ratio, power density, and time. The results showed that protein recovery rate and conversion rate increased by 6.08% and 18.63% under the optimal conditions (200 g/L, 28/80 kHz, 5:2 s/s, 600 W/L, and 3 h) compared with conventional enzymolysis, respectively. The macromolecular proteins in hydrolysates were converted into micromolecular peptides (< 500 Da) when treated by DFSU, and antioxidant activity and angiotensin-I-converting enzyme (ACE) inhibitory activity of hydrolysates were increased. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images illustrated the microstructure changes of feather protein particles in the ultrasound-assisted enzymatic hydrolysates of HFM (UEH), including more porous, smaller, and more uniform. Additionally, the conformation of protein molecules was significantly affected (P < 0.05), including the increase in free sulfhydryl (SH), the decrease in disulfide bond (SS) and surface hydrophobicity (H0). Fourier transform infrared (FTIR) spectra analysis further showed that the secondary structure of feather proteins was modified with a reduction in α-helix, ß-turn, and ß-sheet, while an increase in random coil content was observed. These results indicated that DFSU could be a promising method to enhance high-concentration HFM for preparing peptide-rich hydrolysates with high antioxidant activity and ACE inhibitory activity.

Effect of oral administration of a single bolus of six different protein sources on digestive physiology of red seabream Pagrus major juveniles.

To reveal direct effects of various protein sources on digestive physiology of red seabream, Pagrus major (38.5 ± 0.4 g), six different protein sources of fishmeal (FM), soybean meal (SBM), corn gluten meal (CGM), soy protein concentrate (SPC), poultry by-product meal (PBM), and poultry-feather meal (PFM) were orally administered to fish (2 mg protein/g body weight) and sampled at 1.5 h and 3 h after administration. Gallbladder weight of fish administered FM, PBM, and PFM decreased after administration (p < 0.0001), while no difference was observed in the other ingredients compared to a non-protein sham control group, indicating that animal protein sources could more strongly stimulate bile secretion than plant protein sources in red seabream. Trypsin and chymotrypsin activity in the intestinal content markedly increased by the FM, SBM, and PFM administration (p < 0.0001). Lipase and amylase activity was also increased by FM and SBM but also by CGM for lipase and by PBM and PFM for amylase (p < 0.0001). These indicate that stimulation effect of the secretion of digestive enzymes is largely different among the protein sources. This might be due to the absorptive capacity of the protein source since intestinal absorption parameter genes (anpep, cpa, ggt1, and atp1a2) also increased by the FM, SBM, PBM or PFM (p < 0.05). In addition to the secretion levels of bile and digestive enzymes, gene expression levels of bile related genes (cyp7a1, cyp8b1, and shp) and digestion-regulating genes (casr and cck) were increased by the FM, SBM, PFM, and/or PBM administration, suggesting that animal proteins and SBM could be potent digestive stimulants compared to CGM and SPC. This study first revealed that single protein sources directly influence digestive enzyme secretion and bile secretion in fish. Information about the direct effect of each single source on digestive physiology could help to design feed formulation with less fishmeal.

Keratinase improves the growth performance, meat quality and redox status of broiler chickens fed a diet containing feather meal.

The objective of this study was to assess the effects of dietary supplementation of keratinase on the production of broilers fed a diet containing feather meal. A total of 162 1-d-old Cobb 500 male broiler (n = 9 cages/diet with 6 chicks/cage) were randomly allocated to 3 dietary treatments. The broilers were fed a corn-soybean-feather meal based diet (BD), or BD supplemented with keratinase at 100,000 or 200,000 U/kg for 6 weeks. Compared to the control, dietary supplementation with 200,000 U/kg keratinase increased (P < 0.05) body weight gain (3.6-4.3%) and reduced feed conversion ratio (2.4-5.6%) during the various experimental periods, and also improved (P < 0.05) apparent total tract digestibility of ash and calcium by 45.0% and 8.8%, respectively. Meanwhile, dietary supplementation of keratinase at 100,000 U/kg reduced (P < 0.05) the drip loss (29.2%), while 200,000 U/kg keratinase supplementation increased (P < 0.05) the pH value (1.6%) at 45 min and decreased (P < 0.05) the lightness (L* value; 13.6%) and drip loss (22.1%) of pectoral muscle. Moreover, dietary supplementation of keratinase at both levels of 100,000 and 200,000 U/kg increased (P < 0.05) Glutathione peroxidase activity (82.5-87.5%) and decreased the Malondialdehyde concentration (14.5-18.3%) in the pectoral muscle. In conclusion, dietary supplementation of keratinase at 200,000 U/kg can improve the performance, meat quality, apparent total tract digestibility of nutrients, and redox status of broiler chickens fed a diet containing feather meal.

Energy value of hydrolyzed feather meal and flash-dried poultry protein for broiler chickens and pigs.

Three experiments were conducted to determine the metabolizable energy (ME) and nitrogen-corrected ME (MEn) contents of hydrolyzed feather meal (HFM) and flash-dried poultry protein (FDPP) for broiler chickens and to determine their digestible energy (DE) and ME for pigs. The energy-yielding ingredients in a reference diet (RD) were replaced at 0, 75, or 150 g/kg by HFM in experiment (Exp.) 1; at 0, 75, or 150 g/kg by FDPP in Exp. 2; and at 0, 150 g/kg HFM, or 150 g/kg FDPP in Exp. 3. Birds were fed a standard broiler starter diet from hatch to days 18 and 17 for respective Exp. 1 and 2, following which 144 birds (8 replicate cages of 6 birds per cage) were assigned to the three experimental diets in a randomized complete block design with body weight as the blocking factor. Experimental diets were fed for 5 d, and excreta were collected during the last 3 d. Twenty-four 20-kg barrows, individually housed in metabolic crates equipped with a feeder and drinker, were used in Exp. 3. The barrows were assigned to the three experimental diets in a randomized complete block design with body weight as a blocking factor. Following a 5-d adaptation period, feces and urine were collected for 5 d in a total collection method. Data were used to determine the regression-derived ME and MEn of HFM and FDPP for broiler chickens in Exp. 1 and 2, respectively. The DE and ME of HFM and FDPP for pigs in Exp. 3 were determined using the difference procedure. In Exp. 1, the inclusion of HFM linearly increased (P < 0.05) ME from 3,231 to 3,368 kcal/kg DM for 0 to 150 g/kg replacement of RD. The total tract retention of DM and metabolizability of energy linearly increased (P < 0.05) as replacement of RD with FDPP increased from 0 to 150 g/kg in Exp. 2. Inclusion of FDPP linearly increased (P < 0.01) ME from 3,425 to 3,591 kcal/kg DM. In Exp. 3, the diets containing 150 g/kg HFM or FDPP induced greater (P < 0.05) fecal DM and energy losses than the RD; however, the digestibility of energy across the three experimental diets was not different. The respective regression-derived ME and MEn of hydrolyzed feather meal for broiler chickens in the current study were 4,250 and 3,745 kcal/kg DM with corresponding values of 4,710 and 4,081 kcal/kg DM for flash-dried poultry protein. In pigs, 4,783 and 4,405 kcal/kg DM were the respective DE and ME of hydrolyzed feather meal, and 4,553 and 4,320 kcal/kg DM were the corresponding estimates for flash-dried poultry protein.

The animal production industry is presented with the challenge to develop innovative methods to meet future environmental and economic needs. One of the ways through which global animal scientists could combat this onus is to broaden the scope of conventional feed ingredients, most importantly are those feed ingredients that could supply dietary energy. The current research evaluated the energy values of two feed ingredients: hydrolyzed feather meal (HFM) and flash-dried poultry protein (FDPP) for broiler chickens and pigs. The utilizable proportions in the test ingredients were derived as digestible energy (DE), metabolizable energy (ME), and nitrogen-corrected metabolizable energy (MEn) on a dry matter (DM) basis. The derived ME and MEn concentrations in HFM were 4,250 and 3,745 kcal/kg DM, whereas those in FDPP were 4,710 and 4,081 kcal/kg DM, respectively, for broiler chickens. The respective DE and ME concentrations in HFM and FDPP for pigs were 4,783 and 4,405 kcal/kg DM and 4,553 and 4,320 kcal/kg DM. Using a combination of regression method and difference procedure, we showed that hydrolyzed feather meal and flash-dried poultry protein have substantial energy values.

Systematic assessment of acquisition and data-processing parameters in the suspect screening of veterinary drugs in archive matrices using LC-HRMS.

Monitoring strategies for veterinary drugs in products of animal origin are shifting towards a more risk-based approach. Such strategies not only target a limited number of predefined .substances but also facilitate detection of unexpected substances. By combining the use of archive matrices such as feather meal with suspect-screening methods, early detection of new hazards in the food and feed industry can be achieved. Effective application of such strategies is hampered by complex data interpretation and therefore, targeted data analysis is commonly applied. In this study, the performance of a suspect-screening data processing workflow using a suspect list or the online spectral database mzCloudTM was explored to facilitate detection of veterinary drugs in archive matrices. Data evaluation parameters specifically investigated for application of a suspect list were mass tolerance and the addition or omission of retention times. Application of a mass tolerance of 1.5 ppm leads to an increase in the number of false positives, as does omission of retention times in the suspect list. Different acquisition modes yielding different qualities of MS2 data were studied and proved to be a critical factor, where data-dependent acquisition is preferred when matching to the mzCloudTM database. Using this approach, it is possible to search for compounds on a dedicated suspect list based on the exact mass and retention times and, at the same time, detect unexpected compounds without a priori information. A pilot study was conducted and fourteen different antibiotics were detected (and confirmed by MS/MS). Three of these antibiotics were not included in the suspect list. The optimised suspect-screening method proved to be fit for the purpose of finding veterinary drugs in feather meal, which are not in the scope of the current monitoring methods and therefore, it gives added value in the perspective of a risk-based monitoring.

Dietary Supplementation of Two-Stage Fermented Feather-Soybean Meal Product on Growth Performance and Immunity in Finishing Pigs.

This study investigates the effects of two-stage fermented feather meal-soybean meal product (TSFP) on growth performance, blood characteristics, and immunity of finishing pigs. Firstly, feather meal-soybean meal is subjected to aerobic fermentation with Bacillus subtilis var. natto N21, B. subtilis Da2 and Da15, B. amyloliquefaciens Da6, Da16 for two days, and anaerobic fermentation with B. coagulans L12 for three days. Then, the fermented product is air-dried into an end product-TSFP. Eighty hybrid pigs (Duroc x KHAPS) with equal numbers of both sexes are randomly assigned into 3% fish meal, 0%, 2.5%, or 5.0% TSFP groups with five replicates per group. Our results show that the average daily feed intake and feed conversion rate of TSFP groups are significantly better than the other groups at 0-3 weeks (p < 0.05). The 5% TSFP group significantly increased HDL-C in the blood (p < 0.05), and decreased LDL-C and blood urea nitrogen content (p < 0.05). The lipopolysaccharide (LPS) and concanavalin A (ConA) in 5% TSFP group and interferon-γ (IFN-γ) content in 2.5% and 5% TSFP groups are significantly higher than the other groups (p < 0.05). The phagocytic oxygen burst capacity and serum IgA content of the 5% TSFP group are significantly higher than those of the fishmeal group (p < 0.05). The CD3, CD4, and CD4 + CD8 + T cells subsets in 2.5% and 5% TSFP groups are significantly higher than the control group (p < 0.05). In conclusion, TSFP has a positive effect on the growth performance and immunity of finishing pigs with the best performance on 5% TSFP.

Use of chicken feather meal fermented with Bacillus subtilis in diets to increase the digestive enzymes activity and nutrient digestibility of silver pompano Trachinotus blochii (Lacepede, 1801).

Background: Feather has the potential to be used as a fish feed ingredient because it has high protein content (80-85%), and is rich in amino acids arginine, leucine, isoleucine and valine. However, the protein consists mainly of keratin, which is classified as fiber that is difficult to digest. Therefore, to improve digestibility, the keratin protein is degraded using microbial Bacillus subtilis. This study aimed to determine the digestibility of fermented feather meal (FFM) in silver pompano ( Trachinotus blochii) diets and to observe the histological structure of their intestines after digestion. Methods: The method used was a one factor experiment with five treatments and three replications each, which were: diet without FFM, diet containing 10% FFM, 20%, 30% and 40%. The diets were given to juvenile silver pompano (with average body weight of 8.56 ± 0.18 g) and stocked in 15 similar 20-L plastic jars with 10 fish per jar in a density of 100 L capacity container. The experimental diets were given three times daily at approximately 8.00 AM, 12.00 PM and 5.00 PM to apparent satiation for 60 days. Results: The results showed that the use of FFM increased the activity of digestive enzymes (protease and lipase), but reduced the amylase activity of silver pompano, which was significantly different between treatments (P <0.05). Meanwhile, the diet containing 20% FFM produced the highest feed and protein, which are 37.05% and 67.24%, respectively. This was significantly different from other treatments (P <0.05), and was effectively absorbed by fish intestines. Conclusion: The addition of chicken feather meal fermented with Bacillus subtilis could increase the activity of protease and lipase enzymes and nutrient digestibility of silver pompano but not amylase activity.

Sustainable production, biochemical and molecular characterization of thermo-and-solvent stable alkaline serine keratinase from novel Bacillus pumilus AR57 for promising poultry solid waste management.

The increasing amount of recalcitrant keratinous wastes generated from the poultry industry poses a serious threat to the environment. Keratinase have gained much attention to convert these wastes into valuable products. Ever since primitive feathers first appeared on dinosaurs, microorganisms have evolved to degrade this most recalcitrant keratin. In this study, we identified a promising keratinolytic bacterial strain for bioconversion of poultry solid wastes. A true keratinolytic bacterium was isolated from the slaughterhouse soil and was identified and designated as Bacillus pumilus AR57 by 16S rRNA sequencing. For enhanced keratinase production and rapid keratin degradation, the media components and substrate concentration were optimized through shake flask culture. White chicken feather (1% w/v) was found to be the good substrate concentration for high keratinase production when supplemented with simple medium ingredients. The biochemical characterization reveals astounding results which makes the B. pumilus AR57 keratinase as a novel and unique protease. Optimum activity of the crude enzyme was exhibited at pH 9 and 45 °C. The crude extracellular keratinase was characterized as thermo-and-solvent (DMSO) stable serine keratinase. Bacillus pumilus AR57 showed complete degradation (100%) of white chicken feather (1% w/v) within 18 h when incubated in modified minimal medium supplemented with DMSO (1% v/v) at 150 rpm at 37 °C. Keratinase from modified minimal medium supplemented with DMSO exhibits a half-life of 4 days. Whereas, keratinase from the modified minimal medium fortified with white chicken feather (1% w/v) was stable for 3 h only. Feather meal produced by B. pumilus AR57 was found to be rich in essential amino acids. Hence, we proposed B. pumilus AR57 as a potential candidate for the future application in eco-friendly bioconversion of poultry waste and the keratinase could play a pivotal role in the detergent industry. While feather meal may serve as an alternative to produce animal feed and biofertilizers.

Effects of rumen-protected lysine and histidine on milk production and energy and nitrogen utilization in diets containing hydrolyzed feather meal fed to lactating Jersey cows.

Hydrolyzed feather meal (HFM) is high in crude protein, most of which bypasses rumen degradation when fed to lactating dairy cows, allowing direct supply of AA to the small intestine. Compared with other feeds that are high in bypass protein, such as blood meal or heat-treated soybean meal, HFM is low in His and Lys. The objectives of this study were to determine the effects of supplementing rumen-protected (RP) Lys and His individually or in combination in a diet containing 5% HFM on milk production and composition as well as energy and N partitioning. Twelve multiparous Jersey cows (mean ± SD: 91 ± 18 d in milk) were used in a triplicated 4 × 4 Latin square with 4 periods of 28 d (24-d adaptation and 4-d collection). Throughout the experiment, all cows were fed the same TMR, with HFM included at 5% of diet DM. Cows were grouped by dry matter intake and milk yield, and cows within a group were randomly assigned to 1 of 4 treatments: no RP Lys or RP His; RP Lys only [70 g/d of Ajipro-L (24 g/d of digestible Lys), Ajinomoto Co. Inc., Tokyo, Japan]; RP His only [32 g/d of experimental product (7 g/d of digestible His), Balchem Corp., New Hampton, NY]; or both RP Lys and His. Plasma Lys concentration increased when RP Lys was supplemented without RP His (77.7 vs. 66.0 ± 4.69 µM) but decreased when RP Lys was supplemented with RP His (71.4 vs. 75.0 ± 4.69 µM). Plasma concentration of 3-methylhistidine decreased with RP Lys (3.19 vs. 3.40 ± 0.31 µM). With RP His, plasma concentration of His increased (21.8 vs. 18.7 ± 2.95 µM). For milk production and milk composition, no effects of Lys were observed. Supplementing RP His increased milk yield (22.5 vs. 21.6 ± 2.04 kg/d) and tended to increase milk protein yield (0.801 vs. 0.772 ± 0.051 kg/d). Across treatments, dry matter intake (18.5 ± 0.83 kg/d) and energy supply (32.2 ± 2.24 Mcal of net energy for lactation) were not different. Supplementing RP His did not affect N utilization; however, supplementing RP Lys increased N balance (25 vs. 16 ± 9 g/d). The lack of production responses to RP Lys suggests that Lys was not limiting or that the increase in Lys supply was not large enough to cause an increase in milk protein yield. However, increased N balance and decreased 3-methylhistidine with RP Lys suggest that increased Lys supply increased protein accretion and decreased protein mobilization. Furthermore, His may be a limiting AA in diets containing HFM.

Use of indirect calorimetry to evaluate utilization of energy in lactating Jersey dairy cattle consuming diets with increasing inclusion of hydrolyzed feather meal.

A study using indirect calorimetry and 12 lactating multiparous Jersey cows (53 ± 23 d in milk at the beginning of the experiment; mean ± standard deviation) was conducted to evaluate the utilization of energy in cattle consuming diets containing increasing hydrolyzed feather meal (HFM). A triplicated 4 × 4 Latin square design with 35-d periods (28-d adaption and 4-d collections) was used to compare 4 different dietary treatments. Treatments contained (DM basis) HFM at 0% (0HFM), 3.3% (3.3HFM), 6.7% (6.7MFM), and 10.0% (10HFM). Diets were formulated such that HFM replaced blood meal and nonenzymatically browned soybean meal. With increasing HFM, linear increases were observed for dietary NEL content (1.61, 1.64, 1.69, and 1.70 ± 0.042 Mcal/kg of DM for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively), and the efficiency of converting ME to NEL (0.708, 0.711, 0.717, and 0.719). Apparent total-tract digestibility of CP linearly decreased with increasing HFM (63.4, 61.1, 59.9, and 58.6 ± 1.46% for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively), whereas long-chain fatty acid digestibility increased with increasing HFM (77.2, 77.7, 78.5, and 80.6 ± 1.30%). With increased inclusion of HFM, fecal N excretion increased (199, 230, 239, 237 ± 12.1 g/d for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively), whereas urinary N excretion decreased (166, 151, 155, and 119 ± 14.8 g/d). Increasing the concentration of HFM resulted in a quadratic effect on DMI (19.6, 20.2, 20.3, and 19.1 ± 0.79 kg/d for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively) and milk yield (31.7, 32.0, 31.9, and 29.7 ± 1.32 kg/d). Increasing HFM linearly decreased the milk protein concentration (3.34, 3.29, 3.23, and 3.23 ± 0.158 for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively) and yield (1.05, 1.05, 1.02, and 0.96 ± 0.040 kg). The inclusion of HFM did not affect energy-correct milk yield (average of 39.3 ± 1.54). Results of this study suggest that HFM can increase dietary NEL content compared with blood meal and nonenzymatically browned soybean meal and maintained energy-corrected milk yield; however, feeding HFM at greater than 6.7% of diet DM decreased DMI, and protein availability may have been reduced with increased HFM, leading to a linear decrease in milk protein concentration and yield.

The apoptotic and free radical-scavenging abilities of the protein hydrolysate obtained from chicken feather meal.

This study examined the antioxidant capabilities of peptides derived from chicken feather meal (CFM) protein hydrolysates which were produced using 3 different microbial proteases (Neutrase, Alcalase, and flavourzyme) and tested at varying concentrations, namely 1, 2, and 5% by weight. The highest levels of 2,2-diphenyl-1-picrylhydrazl (DPPH) and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging activities were presented by CFM hydrolysate derived using 5 wt% Neutrase and digested for 4 h. Fractionation of this particular hydrolysate was then performed by applying 10, 5, 3, and 0.65 kDa molecular weight cutoff membranes. It was then determined that the molecular weight (MW) < 0.65 kDa fraction achieved the greatest level of free radical scavenging activity in the context of DPPH and ABTS. The MW < 0.65 kDa fraction then underwent additional fractionation using reverse-phase high-performance liquid chromatography to derive 3 main fractions designated as F1, F2, and F3. All of these fractions presented a high level of activity in DPPH radical scavenging, although no significant ABTS scavenging was observed. Quadrupole time-of-flight tandem mass spectrometry was used in determining the peptide contents of the fractions as Phe-Asp-Asp-Arg-Gly-Arg-X for F1 (FDDRGRX, 875 Da), Val-Thr-Leu-Ala-Val-Thr-Lys-His for F2 (VTLAVTKH, 868 Da), and Val-Ser-Glu-Ile-X-Ser-Ile-Pro-Ile-Ser for F3 (VSEIXSIPIS, 1,055 Da). Moreover, the F2 fraction was shown to be capable of preventing DNA damage induced by hydroxyl radicals, as indicated in tests using the plasmids pKS, pUC19, and pBR322 via the Fenton reaction. This outcome was demonstrated through in vitro antiproliferative activity in human cell lines based on SW620 colon cancer, using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. The F2 fraction at 0.5 wt.% was also shown to be capable of inducing weak early apoptosis, which could be measured by using the Fluorescein isothiocyanate Annexin V Apoptosis Detection Kit with Propidium Iodide Solution. Furthermore, an increase in caspase-3 and caspase-8 activity was observed in SW620 cells following exposure for 24 h and 48 h.

Nitric Oxide Synthesis Inhibition and Anti-Inflammatory Effectof Polypeptide Isolated from Chicken Feather Mealin Lipopolysaccharide-Stimulated RAW 264.7 Macrophages.

Nitric oxide (NO) plays a key role in the pathogenesis of inflammation and has been implicated in endotoxin-induced tissue injury. Chicken feather meal is a rich source of amino acids that may serve as a peptide hydrolysate to inhibit NO activity. Anti-inflammatory hydrolysates of chicken feather meal were prepared and fractionated into five samples based on molecular mass. The smallest fraction (<0.65 kDa) exhibited the highest NO inhibitory activity without cytotoxicity towards macrophage RAW 264.7 cells. Further subfractions were sufficient to obtain amino acid sequences by Q-TOF LC-MS/MS ESI analysis. Of these, the SNPSVAGVR (885.97 Da) peptide and its corresponding pure synthetic peptide have inhibitory activity against NO production by RAW 264.7 cells (IC50=(55.2±0.2) mM) without cytotoxicity. Reverse transcriptase polymerase chain reaction (RT-PCR) and quantitative real-time RT-PCR results revealed that the peptide of the obtained fraction reduced transcript expression levels of the pro-inflammatory cytokines iNOS, TNF-α, COX-2 and IL-6 in lipopolysaccharide-stimulated RAW 264.7 cells. These results suggest that the peptides derived from the chicken feather meal protein could potentially be used as a promising ingredient in functional foods or nutraceuticals against inflammatory diseases.

Bioconversion of Chicken Feather Meal by Aspergillus niger: Simultaneous Enzymes Production Using a Cost-Effective Feedstock Under Solid State Fermentation.

This study reported for the first time the simultaneous production of hydrolytic enzymes by Aspergillus niger under solid state fermentation using chicken feather meal as substrate. The effect of some culture parameters for production of protease, lipase, phytase and keratinase enzymes was evaluated using a central composite rotatable design. The results obtained demonstrated that the independent variables initial moisture of the culture medium and incubation temperature presented as highly significant on the enzymes production. The production of protease and lipase followed a similar profile, in which the highest values of enzymatic activities were detected after 48 h of fermentation. The conduction of the fermentative process using an initial moisture of 50%, 30 °C as incubation temperature and supplementation of the feather meal with 15% wheat bran resulted in higher yields of protease (> 300 U g-1) and lipase (> 90 U g-1) after 48 h and satisfactory values of phytase activity (> 70 U g-1) after 72 h. No significant effects of the independent variables on keratinase production were observed. However, under the selected conditions for the other enzymes, keratinase production reached values higher than 13 U g-1 after 72 h fermentation. Thus, our work contributed to the proposal of an alternative process for the simultaneous production of proteases, lipases, phytases and keratinases in a single and simplified process using chicken feather meal.

Roles of dietary glycine, proline, and hydroxyproline in collagen synthesis and animal growth.

Glycine, proline, and hydroxyproline (Hyp) contribute to 57% of total amino acids (AAs) in collagen, which accounts for one-third of proteins in animals. As the most abundant protein in the body, collagen is essential to maintain the normal structure and strength of connective tissue, such as bones, skin, cartilage, and blood vessels. Mammals, birds, and fish can synthesize: (1) glycine from threonine, serine, choline, and Hyp; (2) proline from arginine; and (3) Hyp from proline residues in collagen, in a cell- and tissue-specific manner. In addition, livestock (e.g., pigs, cattle, and sheep) produces proline from glutamine and glutamate in the small intestine, but this pathway is absent from birds and possibly most fish species. Results of the recent studies indicate that endogenous synthesis of glycine, proline, and Hyp is inadequate for maximal growth, collagen production, or feed efficiency in pigs, chickens, and fish. Although glycine, proline and Hyp, and gelatin can be used as feed additives in animal diets, these ingredients except for glycine are relatively expensive, which precludes their inclusion in practical rations. Alternatively, hydrolyzed feather meal (HFM), which contains 9% glycine, 5% Hyp, and 12% proline, holds great promise as a low cost but abundant dietary source of glycine, Hyp, and proline for ruminants and nonruminants. Because HFM is deficient in most AAs, future research efforts should be directed at improving the bioavailability of its AAs and the balance of AAs in HFM-supplemented diets. Finally, HFM may be used as a feed additive to prevent or ameliorate connective tissue disorders in domestic and aquatic animals.