Digestibility Of Essential Amino Acids Research Articles

Effects of the Replacement of Dietary Fishmeal by the Blend of Tenebrio molitor Meal, Chlorella Meal, Clostridium Autoethanogenum Protein, and Cottonseed Protein Concentrate on Growth, Protein Utilization, and Intestinal Health of Gibel Carp (Carassius gibelio, CAS Ⅴ)

The trial was conducted to investigate the effects of the replacement of dietary fishmeal (FM) by the blend of Tenebrio molitor meal (TMM), Chlorella meal (CM), Clostridium autoethanogenum protein (CAP), cottonseed protein concentrate (CPC) on growth, protein utilization and intestinal health of gibel carp (Carassius gibelio, CAS Ⅴ). The FM-based diet was used as the control, and the blended proteins (TMM: CM: CAP: CPC) at ratios of 1 : 1:8 : 2 (BLEND A), 1 : 1:6 : 4 (BLEND B), and 1 : 1:4 : 6 (BLEND C) were used to replace FM at three levels (33%, 67%, 100%), respectively. The results showed that, compared to the control group, growth performance increased significantly when dietary FM was fully replaced by BLEND B (P<0.05), while decreased by BLEND A (P<0.05). The complete substitution of FM with BLEND B significantly upregulated the mRNA expression of intestinal proinflammatory cytokines, anti-inflammatory cytokines, and tight junction-related genes (P<0.05), improving intestinal tissue morphology and health. And it also significantly increased intestinal trypsin activity (P<0.05), upregulated the mRNA expression of amino acid sensory receptor-related and amino acid or peptide transport-related genes (P<0.05), increased protein apparent digestibility coefficient (P<0.05). The 100% substitution of FM with BLEND A significantly upregulated the mRNA expression of intestinal proinflammatory cytokines and downregulated the mRNA expression of anti-inflammatory cytokine il-10 (P <0.05), reduced intestinal villus height (P<0.05), and decreased protein apparent digestibility coefficient (P<0.05). In conclusion, BLEND B could completely substitute dietary FM and was beneficial to the growth and health of gibel carp. Dietary digestible essential amino acids index (DEEAI) was found as an important indicator and should be higher than 79.5% to meet the maximum growth of fish.

Metabolizable Energy and Amino Acid Digestibility of Soybean Meal from Different Sources for Broiler Chickens Supplemented with Protease.

This study investigated the effect of the serine protease on metabolizable energy and amino acids' digestibility of different soybean meal for broilers. A total of 684 broilers chickens form 14 to 23 d age were distributed with nineteen treatments, six replicates, and six birds per replicate. Nine samples of soybean meal from different regions in Brazil were used, with some samples supplemented with the protease enzyme and others without addition. Apparent and corrected-for-nitrogen-balance metabolizable energy were evaluated, as well as the coefficients of amino acid digestibility. All collected data were submitted to ANOVA at a significance level of 5% and Tukey's test was applied. The results showed that the addition of the protease enzyme significantly increased the values of AME and AMEn in all soybean meal samples. The soybean meal of different origins has significant variations in AME and AMEn. The addition of the protease improved the digestibility of essential amino acids compared to soybean meal without enzyme addition. These results indicate that supplementation with serine protease can improve the metabolizable energy and amino acid digestibility of soybean meal from different regions in the diet of broilers, potentially being an effective strategy to enhance nutrient utilization and animal performance.

Feeding sunflower meal with pullets and laying hens even at a 30% inclusion rate does not impair the ileal digestibility of most amino acids

The use of locally available protein sources in poultry nutrition is challenging for feed manufacturers and farmers. Sunflower meal (SFM) is available in high quantities in several European countries and could be used as a poultry feedstuff at higher inclusion rates. However, its maximum inclusion rate in the diets of different poultry species and age categories is unknown. Pullets and laying hens can probably tolerate higher amounts of SFM, but only limited information is available on these poultry groups. Therefore, a digestibility trial was carried out with 8-week-old layer type pullets and 50-week-old laying hens. Beside a basal diet, SFM was fed at 10, 20 and 30% inclusion rates. Feeding SFM significantly improved the digestibility of essential amino acids (AA) of threonine, valine, lysine, tyrosine, glycine, aspartic acid, and arginine in the pullet diets. No such improvement was found in laying hens. Only the absorption of the two branch-chain AAs, leucin (pullets) and isoleucine (hens), declined due to SFM. The AA digestibility of the SFM itself was also calculated by linear regression. The coefficients were, in all cases, higher in hens than in pullets. Comparing the measured digestibility coefficients of SFM with table values, it can be concluded that high variance exists because of the differences in the methodology and the test animals in the digestibility trials. From the present trial, it can be concluded that SFM can entirely replace extracted soybean meal in pullet and layer diets, without negative effects on the protein digestion of birds.

Effects of different black soldier fly larvae products on slow-growing broiler performance and carcass characteristics

Black soldier fly (BSF) larvae have gained significant attention as ingredients for poultry feed to improve value chain circularity and sustainability. BSF larvae contain bioactive compounds which can potentially improve broiler health and thereby performance. However, the functionality of bioactive compounds likely depends on how larvae are processed prior to feeding and to which extent larvae products are included in the diet. This may explain the variable results reported in literature on broiler performance and carcass characteristics when feeding them different types of BSF larvae products at different inclusion levels. Therefore, the present research aimed to investigate the effects of different BSF larvae products and inclusion levels in diets on performance and carcass characteristics of slow-growing broilers.The experiment started with 1,728 one-day-old slow-growing male broilers (Hubbard JA757). Nine dietary treatments were used, each replicated eight times. One group of broilers was given a control diet. The following BSF larvae products were investigated: live larvae, a combination of BSF larvae meal and oil mimicking the nutritional composition of the live larvae, and BSF larvae meal and oil separately. All insect products were tested at two inclusion levels. All diet programs were nutritionally comparable (isoenergetic and based on balanced levels of digestible essential amino acids). During the seven-week trial, several performance parameters and carcass characteristics were measured.The results show that comparable or better broiler performance was achieved with the inclusion of BSF larvae products in the diets compared to the control. Based on the feed conversion ratio (FCR), the unprocessed larvae product and the highest inclusion level led to the most favorable results. Carcass characteristics remained unchanged when BSF larvae products were used in the diets compared to the control group, indicating favorable production output. The BSF larvae products investigated seem suitable feed ingredients for broilers at the current levels tested, generating performance benefits.

Nutritional value of Spanish Camelina sativa co-products for pigs

This study evaluated and compared the digestible energy (DE) and metabolizable energy (ME) and the coefficient of ileal standardized digestibility (CISD) of crude protein (CP) and amino acids (AA) in camelina expellers (CAE) and camelina meal (CAM) for growing pigs. In Exp. 1, thirty-six barrows Pietrain × (Landrace × Large White) of 61.8 ± 2.83 kg body weight were allotted to 6 diets, a basal corn-soybean meal diet and 5 diets in which a proportion of the corn and soybean meal in the basal diet was replaced by CAE (100, 200 or 300 g/kg) or CAM (100 or 200 g/kg). The experiment lasted 15 days and during the last 5 days the total amount of feces and urine were collected to calculate the energy metabolizability of diets. The CTTAD of energy and DE and ME concentration in CAE and CAM were calculated by the difference procedure as well as by the regression method. In Exp. 2, thirty-three barrows Pietrain × (Landrace × Large White) of 82.0 ± 2.57 kg body weight were allotted to three treatments, two cornstarch-based diets containing 350 g/kg CAE or 300 g/kg CAM as the sole source of CP and AA and a N-free diet. After 7 days of feeding, animals were euthanized and ileal digesta were sampled. The CISD of AA on CAE and CAM was determined using the direct method. Camelina meal had a greater concentration of CP and AA and a lower ether extract than CAE. The most abundant indispensable AA were arginine, leucine, valine, and lysine in both ingredients (26.3, 21.9, 19.1 and 16.2 g/kg dry matter (DM) in average, respectively). Camelina expellers contained 8.0 g/kg DM more soluble and 4.6 g/kg DM less insoluble fiber than CAM. The CTTAD of energy was 0.682 and 0.665 in CAE and CAM, respectively, when calculated using the difference method, and 0.665 and 0.655 in CAE and CAM, respectively, when estimated via the regression method. The DE and ME were on average greater (P < 0.05) for CAE compared with CAM both, using the difference or the regression method (DE, in average:14.3 MJ/kg DM and 13.1 MJ/kg DM, respectively and ME, in average: 14.1 MJ/kg DM and 12.9 MJ/kg DM, respectively). Between methods, no statistical differences were detected. The CISD of CP was greater (P < 0.05) in CAM compared with CAE (0.579 in CAE and 0.670 in CAM). The most digestible essential AA in both ingredients were methionine, arginine and histidine, with average digestibilities of 0.77, 0.75 and 0.83, respectively. The CISD of leucine and cysteine was greater in CAM compared with CAE (P < 0.05). In conclusion, CAE had greater energy value than CAM, whereas the digestibility of leucine and cysteine was less in CAE than in CAM, probably due to the greater concentration of soluble dietary fiber in CAE.

Evaluation of nutritional quality for weaner piglets of a new methanotrophic microbial cell-derived protein feed

This study aimed to test the hypothesis that a new methanotrophic microbial cell protein (MCP) product, Uniprotein®, has a protein value comparable to other high-quality feeds for weaner piglets. Two experiments were conducted. Experiment 1 was a balanced 6 × 6 Latin square design experiment with six ileal cannulated castrated pigs (start weight 30.2 ± 1.4 kg). They were fed six different diets (one diet did not belong to this study) over six periods, each of one week duration. Four of the diets contained 180 g crude protein (CP)/kg as-fed with either MCP, potato protein (PP), fishmeal (FM), or soy protein concentrate as the sole N-source. The fifth diet was N-free. Experiment 2 was a dose-response trial, where piglets during the first 14 days post-weaning were fed diets including increasing amounts of MCP (0, 30.0, 60.0, or 100.0 g MCP/kg as-fed, equivalent to 0, 112, 221 and 359 g microbial-derived CP/kg diet CP) at the expense of FM and PP. Crystaline CP, Lys, Met, Thr, Trp and Val were added to minimize differences across diets, and no medicinal zinc was added to any of the diets. In experiment 1, MCP had the second highest content of essential amino acids (EAA), but the lowest coefficient of standardized ileal digestibility for all EAA except Lys (P < 0.001). However, when contents of ileal digestible EAA were expressed relative to contents of ileal digestible Lys, MCP complied with Danish nutrient recommendations for weaner piglets for 7 out of 9 EAA, and with particularly high levels of digestible Met and Trp. Microbial cell protein had a superior profile as compared to FM for digestible EAA relative to digestible Lys. In experiment 2, MCP could constitute up to 221 g CP/kg diet without any addition of medicinal zinc during the first 14 days post-weaning without any negative impacts on daily weight gain or feed efficiency (gain:feed) compared to the control diet (0 MCP). In conclusion, MCP fulfills Danish recommendations for EAA composition for most EAA and can replace other high quality protein sources to constitute up to 22% of diet CP for weaner piglets without compromising piglet performance.

Research Note: Amylase supplementation improves starch and amino acids digestibility of faba bean for broilers

This study aimed to investigate the effect of amylase on the nutritional value and nitrogen-corrected apparent metabolizable energy (AMEN) of faba bean (FB) seeds in broiler chicken nutrition. The study was conducted on a total of 84, one-day-old male broiler chickens (Ross 308). The birds were fed a reference corn-soybean meal diet form d 1 to 16, and they were divided into three groups (1st day). The first group (1) was fed the same reference diet as in the first part, whereas 50% of the reference diet was replaced by FB seeds in experimental groups (2 and 3). Group 3 was supplemented with amylase, which contained 0.14 g/kg dry matter (DM). At the end of the study period, excreta and digesta samples were collected from all groups to estimate the nutritional value. Some fraction of starch found in the seeds was part of starch which is resistant to digestion (143.9 g/kg DM). The addition of exogenous amylase to the diet increased the apparent ileal digestibility of DM, CP, and starch in FB seeds. The AMEN value increased as a result of enzyme addition (P < 0.05). The group 3 showed higher apparent ileal digestibility of essential amino acids (Lys, Leu, Phe, His) as well as nonessential amino acids (Tyr, Ala, Pro) in FB seeds. It could be concluded that FB seeds supplemented with exogenous amylase have a greater nutrition value for broiler chickens.

Digestibilidad proteica de semillas de Pajuro (Erythrina edulis Triana) sometidas a cocción tradicional

The protein digestibility of pajuro seeds (Erythrina edulis Triana) was determined after the conventional cooking process. The processed seeds were dried, ground and incorporated into isoproteic and isocaloric diets for evaluation with Holtzman rats. The results were expressed in terms of means and standard deviations. A one-way analysis of variance (ANOVA) was performed with Tukey's multiple comparison test to determine significant differences (p &lt;0.05) in the proximal composition values ​​and a correlation analysis between protein consumption / gains weight and feed intake / weight gain. A protein value of 20.58 was obtained in the cooked straw seeds, and values ​​of 25.89, 2.97 and 45.56 for feed consumption, weight gain and specific growth rate respectively. Regarding the protein quality indicators, a positive nitrogen balance was obtained with a value of 0.19, biological value of 65.52%, apparent digestibility of 67.44% and true digestibility of 76.74%; likewise, taking into account the presence of sulfur amino acids as limiting factors, a value of 0.36 was determined for the theoretical count of amino acids, a theoretical count of amino acids corrected for digestibility of 28 and a theoretical count of digestible essential amino acids of 26. These results place traditional cooking as an alternative to facilitate the consumption of pajuro seeds produced in the tropical Andes, thus improving its use and satisfaction of consumer needs; however, supplementation with other food sources or incorporation of synthetic amino acids is necessary to replace the presence of limiting amino acids.

Three-step in vitro digestion model for evaluating and predicting fecal odor emission from growing pigs with different dietary protein intakes.

ObjectiveThe objective of this study was to select an effective in vitro digestion–fermentation model to estimate the effect of decreasing dietary crude protein (CP) on odor emission during pig production and to suggest potential prediction markers through in vitro and in vivo experiments.MethodsIn the in vitro experiment, three diet formulations with different CP contents (170 g/kg, 150 g/kg, and 130 g/kg) but containing the same standardized ileal digestible essential amino acids (SID-EAA) were assessed. Each diet was evaluated by two different in vitro gastric-intestinal phase digestion methods (flask and dialysis), combined with fresh pig feces-ferment inoculation. Eighteen growing barrows (31.9±1.6 kg) were divided into three groups: control diet (180 g CP/kg, without SID-EAA adjustment), 170 g CP/kg diet, and 150 g CP/kg diet for 4 weeks.ResultsThe in vitro digestion results indicated that in vitro digestibility was affected by the gastric-intestinal phase digestion method and dietary CP level. According to the gas kinetic and digestibility results, the dialysis method showed greater distinguishability for dietary CP level adjustment. Nitrogen-related odor compounds (NH3-N, indole, p-cresol, and skatole) were highly correlated with urease and protease activity. The feeding study indicated that both EAA-adjusted diets resulted in a lower odor emission especially in p-cresol and skatole. Both protease and urease activity in feces were also closely related to odor emissions from nitrogen metabolism compounds.ConclusionDialysis digestion in the gastric-intestinal phase followed by fresh fecal inoculation fermentation is suitable for in vitro diet evaluation. The enzyme activity in the fermentation and the fecal samples might provide a simple and effective estimation tool for nitrogen-related odor emission prediction in both in vitro and in vivo experiments.

Nutritional evaluation of fish protein hydrolysate and its application in piglet production.

This study was conducted to determine the digestible energy (DE), metabolizable energy (ME), and ileal digestibility of amino acids (AA) of fish protein hydrolysate (FPH), and to evaluate the effects of FPH on the performance of piglets. In Exp. 1, the available energy content of FPH was determined by difference methods: 12 barrows with an initial body weight (BW) of 40.0±2.1kg were randomly assigned into two dietary treatments with six replicates per treatment, the treatments contained a corn basal diet and an experimental diet in which 20% corn was replaced by FPH. The experiment lasted for 12 d, with 7 d adaptation period followed by 5 d total collection of feces and urine. In Exp. 2, the standardized ileal digestibility (SID) of AA in FPH by the N-free method was determined, 12 barrows (initial BW of 35.3±1.8kg) with ileal T-cannulas were randomly allotted into two treatments with six replicates per treatment, and the dietary treatments consisted of an experimental diet and a N-free diet. The experiment was lasted for 7 d, with 5 d adaptation period followed by 2 d collection of ileal digesta. In Exp. 3, the effect of FPH on the performance of piglets was conducted. One hundred ninety-two piglets (initial BW of 8.10±1.8kg) were randomly allotted into four treatments with six replicates per treatment. The treatments were a control diet with fish meal (FM) and part or all FM was replaced by FPH, receiving diets containing 2%, 3%, or 5% FPH. The experiment lasted for 28 d. Results showed that in Exp. 1, the DE and ME of FPH were 21.12 and 20.28 MJ/kg. In Exp. 2, the SID of Lys, Met, Thr, and Trp was 79.99%, 87.17%, 68.29%, and 71.53%, respectively. In Exp. 3, addition of 3% FPH increased nutrient digestibility and volatile fatty acid content in feces. Addition of 5% FPH increased the average daily feed intake (ADFI), significantly increased (P < 0.05) the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and immunoglobulin A (IgA), while significantly decreased (P<0.05) the average daily gain (ADG). In conclusion, FPH had a high value of digestible energy and ileal digestible essential amino acids, and could improve nutrient digestibility, immunity, antioxidant capacity, and intestinal health of piglets, while adverse to nitrogen deposition in piglets.

Effect of feeding level on the digestibility of alternative protein-rich ingredients for African catfish (Clarias gariepinus)

Apparent digestibility coefficients (ADC) of nutrients and individual amino acids (AA) for 13 feed ingredients as affected by feeding level were determined for African catfish, a species of economic importance in Africa. Results from two trials are reported. In each trial, ADC were determined using a reference diet and test diets with yttrium oxide as indicator. Juvenile African catfish (averaging 53.9 g, trial 1; 40.4 g, trial 2) were stocked in tanks connected to a common recirculation aquaculture system. Ingredients tested included hydrolysed feather meal (HFM), fishmeal (FM), insect meal (IM), soybean meal (SBM), sunflower meal (SFM), poultry meal (PM), corn dried distillers grains with solubles (CDDGS), faba beans (FB), lupine meal (LM), pea protein (PP), guar meal (GM), canola meal (CM) and yeast meal (YM). The effect of feeding level on ADC was determined by feeding fish restrictively (80% satiation) for 5 weeks and subsequently to apparent satiation for 2 weeks. Inclusion of yeast meal at 30% resulted in low palatability. ADC of nutrients were significantly affected by feeding level (except for fat and carbohydrate), but the effect was ingredient-dependent. African catfish was able to digest protein very effectively in almost all tested ingredients with ADC values ranging from 85.6 to 105.1% across feeding periods. Several ingredients tested, including animal protein ingredients and YM had similar high ADC for dry matter as FM. However, the ADC of AA differ among ingredients, indicating a need for digestible amino acid profile data. Methionine (Met) was the first limiting essential amino acid in HFM, FB, and LM with values ranging from 5−6 g/kg, expressed as digestible Met (dMet) per unit of digestible protein (DP), compared to FM (27 g dMet/kg DP). IM had comparable and sometimes higher overall digestible essential AA values compared to FM, except for methionine and lysine. For oilseeds and legumes, SBM tended to be the best quality AA source, as it had the highest digestible essential amino acid profile. These data provide information concerning nutrient and digestible AA values, which will allow a more efficient use of alternative ingredients in African catfish diets. Formulating diets based on the digestible AA in ingredients will aid precise feed formulation, thereby minimising economic losses and reducing the environmental footprint of aquaculture production.

Effect of a novel consensus bacterial 6-phytase variant in grower pigs fed corn-soybean meal-based diets formulated with a full nutrient matrix and no added inorganic phosphorus.

The capacity of a novel consensus bacterial 6-phytase variant (PhyG) to entirely replace dietary inorganic phosphorus (Pi) source in grower pigs fed diets with reduction of calcium (Ca), net energy (NE), and digestible amino acids (AA) was evaluated, using growth performance and apparent total tract digestibility (ATTD) of nutrients as outcome measures. A total of 352 mixed-sex pigs (initial BW 23.4 kg) were randomized to 4 treatments, 8 pigs/pen, and 11 pens/treatment. Diets were corn-soybean meal-based and formulated by phase (grower 1, 25 to 50 and grower 2, 50 to 75 kg BW). The positive control diet (PC) provided adequate nutrients and a negative control diet (NC) was formulated without Pi (1.2 g/kg ATTD P) and reduced in Ca (-0.12 to -0.13 percentage points), NE (-32 kcal/kg), and digestible essential AA (-0.004 to -0.026 percentage points) vs. PC. Two further treatments comprised the NC plus 500 or 1,000 FTU/kg of PhyG. Data were analyzed by ANOVA, mean contrasts and orthogonal polynomial regression. Nutrient reductions in the NC reduced (P < 0.05) average daily gain (ADG) during grower 1 and overall (73 to 136 d of age), increased (P < 0.05) feed conversion ratio (FCR) during grower 1 and overall and tended to reduce (P < 0.1) average daily feed intake (ADFI) during grower 2 and overall, vs. PC. Phytase supplementation improved (P < 0.05) FCR during grower 1, ADG during grower 2 and overall, ATTD of DM and P, and tended to improve DE (P = 0.053) in a linear dose-dependent manner. PhyG at 1,000 FTU/kg resulted in growth performance (all measures, all phases) equivalent to PC. The findings demonstrate that PhyG at 1,000 FTU/kg totally replaced Pi in complex grower pig diets containing industrial co-products, compensated a full nutrient matrix reduction and maintained performance.

ПОКАЗАТЕЛИ КАЧЕСТВА МЯСА ЦЫПЛЯТ-БРОЙЛЕРОВ (Gallusgallus L.) ПРИ ИСПОЛЬЗОВАНИИ В РАЦИОНАХ ФЕРМЕНТАТИВНЫХ ГИДРОЛИЗАТОВ ПЕРА И КОЛЛАГЕНА

The deficit of feed-grade protein for the productive animals and poultry is presently propelling the interest toward the use of the hydrolysates of slaughter wastes as the potential protein sources. The slaughter wastes of poultry (feathers, intestines, blood, heads, shanks, meat-bone residues of the deboning) can mount up to one third of the initial bodyweight. Earlier we have developed the two-stage technology of easily digestible protein additives involving the hydrolysis and fermentation of protein from poultry slaughter wastes (primarily keratin from feathers and collagen from meat-bone residue). The study presented is a pioneer evidence that the substitution of these additives for fishmeal in diets for broilers provides more rapid growth and does not deteriorate the protein, fatty and amino acid profiles, concentrations of non-peptide, peptide and residual nitrogen, technological properties of meat. The study was performed in 2019 and aimed at the comparative evaluation of meat quality at 38 and 49 days of age in floor-housed broilers fed standard diet and three experimental diets with these hydrolysates. The broilers (cross Ross-308, 35 birds per treatment) kept in conditions of the Center for Genetics & Selection “EPH Zagorskoye” (Moscow Province) were allotted to four treatments partially slaughtered at 38 days of age and partially at 49 days. Control treatment 1 was fed a standard broiler diet with fishmeal; in experimental treatments fishmeal was substituted by enzymatic hydrolysate of feathers (treatment 2), enzymatic hydrolysate of collagen (treatment 3), mixture of these two hydrolysates with addition of probiotic Bacell M (0.2 %), and bran (0.5 %) as a source of vegetable fiber (treatment 4). It was found that supplementation of diets with the hydrolysates of keratin and collagen significantly improved live bodyweight in broilers by 8.78-10.89 % in compare to control (p £ 0.001). The content of peptide nitrogen in breast muscles in treatments 1 and 4 tended to grow with the increase in slaughter age (in treatment 1 from 0.07 at 38 days to 0.27 % at 49 days; in treatment 4 from 0.07 to 0.35 %). The number of protein fractions (with molecular weights from 100 to < 20 KDa) in meat increased with slaughter age with all studied diets. Protein of breast muscles contained more isoleucine, leucine, valine, and phenylalanine at 38 and 49 days of age in compare to thigh meat with all studied diets. The digestibility of essential amino acids in breast muscles in treatment 4 grew from 81.78 % with slaughter at 38 days to 90.29 % at 49 days. Evaluation of biological value of meat revealed better balanced ratios of the essential amino acids in breast muscles in control treatment at 38 days of age (the difference in the amino acid score 70.53 %) and in treatment 4 at 49 days of age (the difference in the amino acid score 66.48 %). In thigh meat this difference was higher in treatment 3 at 38 days of age (59.69 %) and in treatment 4 at 49 days of age (61.43 %). There were no significant differences between the treatments in concentrations of fatty acids in meat. The conclusion was made that the use of new protein additives based on the enzymatic hydrolysates of feathers and collagen in diets for broilers does not deteriorate the parameters of meat quality.

THE EFFECTS OF ENZYMATIC HYDROLYSATES OF FEATHERS AND COLLAGEN IN DIETS FOR BROILER CHICKS (Gallus gallus L.) ON MEAT QUALITY

The deficit of feed-grade protein for the productive animals and poultry is presently propelling the interest toward the use of the hydrolysates of slaughter wastes as the potential protein sources. The slaughter wastes of poultry (feathers, intestines, blood, heads, shanks, meat-bone residues of the deboning) can mount up to one third of the initial bodyweight. Earlier we have developed the two-stage technology of easily digestible protein additives involving the hydrolysis and fermentation of protein from poultry slaughter wastes (primarily keratin from feathers and collagen from meat-bone residue). The study presented is a pioneer evidence that the substitution of these additives for fishmeal in diets for broilers provides more rapid growth and does not deteriorate the protein, fatty and amino acid profiles, concentrations of non-peptide, peptide and residual nitrogen, technological properties of meat. The study was performed in 2019 and aimed at the comparative evaluation of meat quality at 38 and 49 days of age in floor-housed broilers fed standard diet and three experimental diets with these hydrolysates. The broilers (cross Ross-308, 35 birds per treatment) kept in conditions of the Center for Genetics & Selection “EPH Zagorskoye” (Moscow Province) were allotted to four treatments partially slaughtered at 38 days of age and partially at 49 days. Control treatment 1 was fed a standard broiler diet with fishmeal; in experimental treatments fishmeal was substituted by enzymatic hydrolysate of feathers (treatment 2), enzymatic hydrolysate of collagen (treatment 3), mixture of these two hydrolysates with addition of probiotic Bacell M (0.2 %), and bran (0.5 %) as a source of vegetable fiber (treatment 4). It was found that supplementation of diets with the hydrolysates of keratin and collagen significantly improved live bodyweight in broilers by 8.78-10.89 % in compare to control (p £ 0.001). The content of peptide nitrogen in breast muscles in treatments 1 and 4 tended to grow with the increase in slaughter age (in treatment 1 from 0.07 at 38 days to 0.27 % at 49 days; in treatment 4 from 0.07 to 0.35 %). The number of protein fractions (with molecular weights from 100 to < 20 KDa) in meat increased with slaughter age with all studied diets. Protein of breast muscles contained more isoleucine, leucine, valine, and phenylalanine at 38 and 49 days of age in compare to thigh meat with all studied diets. The digestibility of essential amino acids in breast muscles in treatment 4 grew from 81.78 % with slaughter at 38 days to 90.29 % at 49 days. Evaluation of biological value of meat revealed better balanced ratios of the essential amino acids in breast muscles in control treatment at 38 days of age (the difference in the amino acid score 70.53 %) and in treatment 4 at 49 days of age (the difference in the amino acid score 66.48 %). In thigh meat this difference was higher in treatment 3 at 38 days of age (59.69 %) and in treatment 4 at 49 days of age (61.43 %). There were no significant differences between the treatments in concentrations of fatty acids in meat. The conclusion was made that the use of new protein additives based on the enzymatic hydrolysates of feathers and collagen in diets for broilers does not deteriorate the parameters of meat quality.

Effect of protease supplementation on the digestibility of amino acids in animal-origin meals for broiler diets

Enzymes benefit digestion and absorption of the ingredients and their addition to an animal-origin meal (AOM) can improve its nutritional quality. This research aimed to evaluate the effect of protease on nutrient digestibility, amino acids, and metabolism of AOM energy for broilers. Four hundred and eighty broiler chickens were distributed in a completely randomized design (4 × 2 factorial scheme), eight treatments, six replicates containing 10 birds/replicate. Treatments consisted of poultry viscera meal, swine viscera meal (SVM), bovine meat and bone meal, and basal diet; with and without protease addition. Two tests were performed. In the first test, the total excreta collection method was used with birds at 13 to 20 days of age and 25% of the reference feed was replaced by AOM. In the second test, a protein-free diet was administered to birds at 21 to 24 days of age and AOM replaced 25% of the starch. The inclusion of protease increased the apparent metabolizable energy corrected for nitrogen balance of SVM by 15.99% and the apparent metabolizable crude energy by 5.7%, and it also raised the coefficient of true ileal digestibility of the amino acids in the AOMs by 5.67% on average. The inclusion of protease improved the apparent metabolizable crude energy of AOMs, apparent metabolizable dry matter of bovine meat and bone meal, coefficient of true ileal digestibility of essential amino acids, and apparent metabolizable energy corrected for nitrogen balance of SVM. Dietary supplementation of protease may be a potential strategy to improve the digestibility of amino acids for broilers, a possibility of using animal-origin meals as a protein source of diets.

Assessment of the ideal ratios of digestible essential amino acids for pacu,Piaractus mesopotamicus, juveniles by the amino acid deletion method

AbstractThe present study aimed to determine the ideal ratios of digestible essential amino acids (EAAs) for pacu (Piaractus mesopotamicus) juveniles by the amino acid (AA) deletion method. A completely randomized design which consisted of 11 treatments and three replicates each was used. The treatments included a control diet (CD) containing 55% of nonpurified natural ingredients and 45% of purified synthetic amino acids and ingredients, and other ten isonitrogenous and isoenergetic EAA limiting diets (LDs), each being deficient in 44.4 ± 0.02% of the respective EAA. Pacu juveniles with initial average body weight of 6.22 ± 0.09 g were distributed among 33 fiber glass tanks. Fish were fed with semipurified and extruded diets for 113 days two times a day until apparent satiation. The ideal ratio of each dietary EAA was calculated on the basis of the relationship between body N retention and amount of EAA deleted from the respective EAA LD. Based on the AA deletion method, the ideal ratios of digestible EAAs for pacu juveniles, relative to lysine requirement of 100% were estimated as: methionine 14.6%, threonine 35.0%, tryptophan 6.6%, arginine 62.8%, histidine 13.6%, isoleucine 26.3%, leucine 43.7%, phenylalanine 27.2%, and valine 35.8%.

Natural Fermentation of Cowpea (Vigna unguiculata) Flour Improves the Nutritive Utilization of Indispensable Amino Acids and Phosphorus by Growing Rats.

Cowpea (Vigna unguiculata) is among the most cultivated legumes, with interesting agronomic and environmental properties, and great potential as a nutritious food. The nutritional value of cowpea can be improved by technological processing. In this study, we showed that natural fermentation improved bioavailability of protein, amino acids, and dietary essential minerals from cowpea in growing rats, thus strengthening its potential value as functional food or food supplement. Forty Wistar albino rats (48 ± 1.8 g), were fed one of four experimental diets (n = 10 rats per diet): casein, raw cowpea, fermented cowpea or fermented and autoclaved cowpea. Despite lower growth indices of raw and fermented cowpea protein (PER, FTI) than casein, fermentation enhanced apparent digestibility of arginine, leucine, lysine, methionine, phenylalanine, tyrosine, and valine, and true digestibility of essential amino acids, except for tyrosine and valine, compared to raw cowpea. On the other hand, autoclaving of fermented cowpea flour decreased apparent, as did true digestibility of sulfur amino acids. Regarding the nutritive utilization of dietary essential minerals, Vigna unguiculata was a good source of available P, Mg, and K, while fermentation significantly improved the availability of P. Overall, cowpea was a good source of digestible essential amino acids and minerals and fermentation significantly improved its nutritional value that was not further enhanced by autoclaving.

Use of precision-fed cecectomized rooster assay and digestible indispensable amino acid scores to characterize plant- and yeast-concentrated proteins for inclusion in canine and feline diets.

Increased consumer interest in high-quality and novel protein sources has driven the demand for the inclusion of protein-rich ingredients in companion animal diets. Novel protein concentrates, with protein contents of at least 50%, have been used to satisfy these consumer demands. However, minimal information is available regarding the macronutrient composition and protein quality of these ingredients that is needed for proper formulation of pet foods. Therefore, the objectives of this study were to determine the macronutrient and amino acid compositions, standardized amino acid digestibility according to the precision-fed rooster assay, and protein quality using digestible indispensable amino acid score (DIAAS like) of pea protein (PP), potato protein (POP), faba bean protein (FBP), soy protein concentrate (SPC), and dried yeast (DY). Precision-fed rooster assays were conducted using cecectomized roosters to calculate standardized amino acid digestibility and true metabolizable energy corrected for nitrogen (TMEn). For all five protein concentrates, all essential amino acids were highly digestible (88.0% to 96.3%, dry matter basis) with differences (P < 0.05) in only lysine, methionine, and tryptophan digestibilities. The TMEn values were highest for POP (4.22 kcal/g) and DY (3.61 kcal/g). The DIAAS-like values for adult dogs indicated that methionine was the first-limiting amino acid in all protein concentrates except POP, where the first-limiting amino acid was tryptophan. Using Association of American Feed Control Officials (AAFCO)-recommended values for adult cats, DIAAS-like values for methionine were lowest (P < 0.05) for FBP at 81.5%, with all other amino acids for all protein concentrates over 100%. The National Research Council (NRC)-recommended allowances for adult cats indicated that DIAAS-like methionine values for PP (92.7%) and FBP (73.8%) were significantly lower (P < 0.05) with these being the first-limiting amino acids, with the remaining amino acids above 100% for the other protein concentrates. The protein quality and high essential amino acid digestibility of these protein concentrates indicate that they would be viable protein sources in canine and feline diets. However, additional complementary protein sources should be included to meet the requirements of all essential amino acids.

Amino acid digestibility of protein and energy ingredients of plant origin in bullfrog (Lithobates catesbeianus)

Due to increasing demand of ingredients of animal origin, studies on the availability of nutrients in ingredients of plant origin are worthy in carnivorous species including bullfrog. This study aimed to determine apparent digestibility coefficients (ADCs) of amino acids (AAs) in three ingredients as plant protein sources (soybean protein concentrate (SPC), corn gluten meal 60 % (CGM), soybean meal (SM)) and two ingredients as plant energy sources (corn grain (CG) and wheat bran (WB)) which commonly use in bullfrog diets. A reference diet and five test diets containing 69.5 % of the reference diet, 30 % of each test ingredient and 0.5 % of chromium (III) oxide as an inert marker were prepared. Among plant protein ingredients, CGM showed better digestibility of essential amino acids (EAAs) (> 80 %) at the three post-metamorphic (initial, growing and finishing) phases of bullfrog development, except tryptophan which presented a low digestibility at growing and finishing phases. Among plant energy ingredients, CG presented better digestibility of AAs at both initial and growing phases than WB which showed better digestibility only at finishing phase. It was observed that methionine and lysine are the most limiting EAAs in tested ingredients, indicating that additional amounts of these AAs should be supplemented when these ingredients are used in bullfrog diets.

Phytase supplementation effects on amino acid digestibility depend on the protein source in the diet but are not related to InsP6 degradation in broiler chickens

The objective was to determine phytase effects on prececal amino acid (AA) digestibility and phytate (InsP6) breakdown when different oilseed meals were used in broiler chicken diets. The study included 14 diets: a corn-soybean meal (SBM) basal diet and 6 diets that contained SBM, rapeseed meal (RSM), and sunflower meal (SFM) with 2 inclusion levels at the expense of corn starch (150 and 300 g/kg SBM or SFM, or 100 and 200 g/kg RSM). Each diet was mixed with or without a phytase supplement of 1,500 FTU/kg. Diets were provided to broilers for 5 D. Digesta from the posterior half of the ileum were collected on day 21. The average essential AA digestibility, calculated by a regression approach, without and with phytase was 84 and 85% (SBM), 74 and 77% (SFM), and 66 and 73% (RSM), respectively. In the diets, phytase effects on AA digestibility were lower owing to other protein sources also present in the diet, but significant. Prececal InsP6 disappearance was significantly affected by interactions between oilseed meal, inclusion level, and phytase supplementation. Overall, prececal InsP6 disappearance was higher in SBM diets (52%) than in SFM diets (38%) and intermediate in RSM diets (43%). Across diets, phytase supplementation effects on prececal InsP6 degradation linearly increased with the InsP6 concentration of the diet up to 12 g/kg DM. The only exception from linearity was the diet with the high inclusion of SFM, which contained 15.9 g InsP6/kg DM. In the ileal content, the concentration of myo-inositol was significantly increased by phytase supplementation, and this effect was highest in the diets that contained SBM as the only oilseed meal. Concentrations of lower inositol phosphates were increased by phytase supplementation, and this effect was most remarkable for Ins(1,2,3,4)P4 and inositol tetrakisphosphates. The study showed that phytase effects on AA digestibility varied among the 3 tested oilseed meals, but these differences were not detectable in the diets containing these meals. Although phytase effects on ileal content of InsP6 and its degradation products were substantial, they were not related to the effects on AA digestibility.