Distribution Of Protein Fractions Research Articles

Influence of pH on protein extraction from Sus scrofa pancreas

The porcine pancreas contains various enzymes, structural, regulatory, secretory, receptor and other biologically active substances that ensure both the functioning of the organ and its biological role in the organism. The aim of this work was to study the influence of pH changes in 0.9% sodium chloride solution used as an extractant on the efficiency of bioactive protein isolation from the porcine pancreas. The extraction was carried out with the 0.9% NaCl, 0.9% NaCl pH=4 and 0.9% NaCl pH= 8.5 with a stirring speed of 400 rpm for 150 min at 4 ºC; the ratio of pancreas: extractant was 1:5, the supernatant was separated by centrifugation. The protein concentration was measured by a biuret reaction on a semi-automatic biochemical analyzer Biochem SA. The proteomic composition of extracts and native pancreas was evaluated by 10% SDS-PAGE according to Laemmli method in the “VE10” chamber. Digital images of electrophoregrams were obtained using a Bio-5000 Plus scanner, edited in a graphic editor and analyzed using ImageJ software. When determining the intensity of protein fractions, it was noted that the use of 0.9% NaCl contributed to a greater yield of proteins with molecular weights of 200 kDa, 150 kDa, 69 kDa, 52 kDa and 33 kDa into the extractant; a pH shift to the acidic area stimulated the yield of fractions with molecular weights of 130 kDa, 50 kDa, 49 kDa, 45 kDa, 40 kDa, 30 kDa and 27kDa, and a pH shift to the alkaline area — only 47 kDa and 42 kDa. Most pancreas proteolytic enzymes have a molecular weight in a range of 34–23kDa, excepting the immature form of carboxypeptidases with MW 45–47kDa. The greatest intensity of protein bands was observed in the region with MW less than 33kDa on the obtained electrophoregrams. The presence of intense protein fractions in the region of molecular weights of less than 50–52kDa and 40kDa was also noted, which may correspond to enzymes such as pancreatic lipase and phospholipase A2, and the presence of protein fractions with MW above 130 kDa corresponding to various types and isoforms of collagen and laminin. In addition, such processes as protein aggregation and proteolysis can also influence the molecular weight distribution of protein fractions.

Влияние сухого созревания на белки мышечной ткани говядины

Meat is an inherent part of human diet. Its quality develops at different stages of production, storage, and processing. In this respect, the stage of aging is especially important. This technology makes it possible to regulate biochemical processes in meat raw materials. Long-term dry aging is a promising method that presupposes conditions that limit the growth of microorganisms. The transformations in the protein component are an important but understudied aspect of meat quality formation during dry aging.
 The research featured Hereford beef carcasses of Siberian breeding. The samples were isolated from the inner part of bone spinal-lumbar cuts after 21, 35, and 42 days of dry aging under the following conditions: 0–1°C, 74–75% relative humidity, 0.5 m/s air velocity. The samples were subjected to dry aging after 24 h at 4°C. The fractional composition of proteins was controlled by vertical electrophoresis in a Mini-Protean Tetra System chamber. The amino acid composition was defined by high-performance liquid chromatography in a Shimadzu LC-20 Prominence liquid chromatograph with a Shimadzu SPD20MA diode-matrix detector and a Kromasil C-18 separation column. The protein digestibility was measured by sequential exposure to pepsin-trypsin proteinase system under simulated gastric digestion.
 Long-time dry aging triggered proteolysis under the action of endogenous enzymes. The electropherogram analysis showed that the proteolytic changes in high-molecular myofibrillar proteins of high-quality beef became more pronounced after a longer maturation period. The distribution of protein fractions by dry aging stages indicated a different rate of degradation of contractile, regulatory, and cytoskeletal proteins. As a result, the structural integrity of muscle fibers degraded, the meat grew tender, and the proteins became more available to digestive enzymes. The amino acid and protein digestibility analyses in vitro demonstrated an increase in the nutritional value of beef and the availability of proteins to the action of proteinases after 42 days of dry aging.
 Long-term dry aging of high-quality beef increased the digestibility of muscle proteins as a result of proteolysis that accompanied the accumulation of low-molecular fractions. According to the amino acid analysis, the optimal result was most pronounced on day 42 as proven by the moderate oxidative changes in proteins.

Serum protein electrophoresis in 26 dogs with chronic hepatitis.

Serum protein electrophoresis (SPE) shows the distribution of protein fractions, helping clinicians to characterize some pathologic processes. Information is lacking in the literature about SPE alterations in dogs with chronic hepatitis (CH). Our aim was to describe SPE alterations in canine CH, to compare SPE results to histologic scores, and to study SPE trends during follow-up. We reviewed retrospectively case data from dogs with a histologic diagnosis of CH. Only cases with SPE, CBC, and serum chemistry results available were included. Dogs were divided into subgroups based on histologic necroinflammatory activity (A) and fibrosis (F) scores (groups A0-1 and A>1; groups F<2 and F≥2). We included 26 dogs; 15 had follow-up SPE. The most common SPE alterations at admission were hypoalbuminemia (n = 16), increases in α1-globulins (n = 11), γ-globulins (n = 11), α2-globulins (n = 8), β2-globulins (n = 7), and β1-globulins (n = 6), and decreased albumin:globulin (A:G) ratios (n = 20). Four of 11 dogs had β-γ bridging. Groups with higher A and F scores had higher β2-globulins. Eleven of 15 dogs with a post-treatment SPE had a decrease in γ-globulins and increase in A:G ratio compared to their T0, although there was no statistically significant difference. Although further studies are warranted, SPE may be useful for monitoring canine CH.

Characterization of protein in cricket (Acheta domesticus), locust (Locusta migratoria), and silk worm pupae (Bombyx mori) insect powders

Nutritional and functional properties of protein were determined for cricket, locust, and silk worm pupae powders, specifically macro-nutrient proximate composition, full amino acid composition, protein pH-solubility, and SDS-PAGE/densitometry. Cricket and locust powders contained >70 g of crude protein/100 g of sample powder (d.b. – dry basis), while silk worm pupae powder >50 g of crude protein/100 g of sample powder (d.b.). Insect powders exceeded FAO/WHO/UNU recommendations for eight of the nine essential amino acids (EAAs) for adults, but not infants. Total EAAs (21.8–23.7 g EAAs/100 g sample; d.b.) was two-times higher than FAO/WHO/UNU recommendations for adults (12.7 g EAAs/100 g sample; d.b.), but only half for infants (46.0 g/100 g; d.b.). Nearly 70% of insect protein dissolved in alkaline pH, while only 7% at pH 4–6. SDS-PAGE/densitometry showed four protein fractions: cuticle proteins, actin-arginine kinase, hemocyanin, and myosin. SDS-PAGE/densitometry also showed proteolysis and various distribution of protein fractions among insect powders. Protein may be efficiently isolated from insects using pH-solubility-precipitation; thus, resulting in isolates with high nutritional and functional quality.

Состав коллагенсодержащих препаратов из медузы ропилемы Rhopilema asamushi Uchida и оценка безопасности их наружного применения

Methods have been developed for obtaining polyfunctional preparations of various degrees of purification from rhopilema jellyfish in the form of collagen and proteoglycane complexes, and their safety for the external use has been assessed. In our study, we used HPLC, SDS-PAGE and IR spectroscopy. The composition (proteins, including collagen, amino acids and carbohydrates) and properties of the obtained preparations were determined. The structure of collagen as a part of the isolated complexes was analyzed, and the degree of preservation of its tertiary structure was shown. Changes in the molecular weight distribution of protein fractions were established for different methods of isolation of the substances. The safety of external use of the obtained drugs was analyzed in terms of acute toxicity, skin irritant and sensitizing action in accordance with the requirements for toxicological studies of ingredients of cosmetics in an experiment on test animals. jellyfish ropilema, collagen, electrophoresis, IR spectroscopy, toxicity, skin irritant effect The authors express their gratitude to P. A. Zadorozhny, Senior Researcher of the Laboratory of Molecular and Elemental Analysis of the Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, for conducting IR spectrometry. The authors are also grateful to O. B. Romanova (Deputy Chief Physician), E. G. Land (Doctor for Sanitary and Hygienic Laboratory Studies), O. A. Stroeva (Biologist of the Vivarium) and G. P. Prikhodko (Veterinarian of the Vivarium), employees of the Center for Hygiene and Epidemiology in Primorsky Krai, for conducting toxicological tests.

The Electrophoretic Pattern of Serum Proteins in Sheep with Naturally Acquired Gastrointestinal Nematode Infections

Abstract The objective of this study was to describe the serum protein pattern in sheep with naturally acquired gastrointestinal parasitosis and to compare the distribution of protein fractions with the results obtained in animals with negative fecal examination results. Fecal and blood samples were taken from twenty-nine sheep positive for nematode eggs and twenty-four animals with negative results of fecal examination. Between the evaluated groups of sheep significant differences were noted in the relative mean values for all protein fractions and for albumin/globulin ratio (p&lt;0.01 and p&lt;0.001). The concentrations of total proteins showed no significant differences between both groups of sheep. The absolute mean values of albumin, α2-globulins and A/G ratio were significantly lower, the mean concentrations of α1-, β-, γ1- and γ2-globulins significantly higher in the nematode positive group of sheep (p&lt;0.01 and p&lt;0.001). In the nematode positive group the protein electrophoretic pattern showed a double α2-zone in three sheep and the γ-globulin zones were characterized by a diffuse higher broad and wide peaks. The presented results indicate that the gastrointestinal parasitic infections in sheep alter the distribution of serum proteins, and suggest their usefulness in animals with unchanged serum protein concentrations. The study brings new findings and extends the knowledge about the metabolic responses and consequences of gastrointestinal parasitic infections in sheep, particularly with regard to alterations in protein metabolism.

Microstructure of kajmak skin layer made during kajmak production

Kajmak is a unique dairy product with a long tradition in Balkan countries and the Middle East. Kajmak skin layers are formed during 60 minutes of kajmak production, influencing the quality and determining the structure of the final product. The influence of milk composition and heat treatments (75-95 °C/5min) on the composition, microstructure and protein distribution of kajmak skin layers was investigated in this study. Microstructure was determined using scanning electron microscopy (SEM), while the distribution of protein fractions was studied by SDS PAGE in reducing and non-reducing conditions. Kajmak skin layers obtained from milk treated at common intense heat regime were characterized with β-LG and α-LA mainly as disulfide-linked complexes, while lower temperature (75 °C) caused the presence of whey proteins in dominantly individual form. More severe treatments (85 °C, 90 °C and 95 °C) caused the full involvement of β-LG in the complexes, since a certain amount of α-LA was found as a monomer. The kajmak skin layer composition, severity of the applied milk heat treatment and the linked whey proteins exhibited a very strong influence on kajmak skin layer microstructure. The microstructure of kajmak skin layer with a low fat content and fat/protein (F/P) ratio was characterized by a compact structure with a dense protein matrix. High fat content and F/P ratio resulted in a dispersive form of the stretched protein network. Kajmak skin layers produced from milk with added whey proteins were characterized by fibrous, thread-like segments, due to the incorporated denatured whey proteins, especially linked β-LG.

ASSESSING THE EFFECT OF THERMAL TREATMENT ON MEAT PROTEINS USING PROTEOMIC METHODS

The results of studying the effect of various temperatures on the protein composition of minced meat from porcine m. longissimus dorsi by two-dimensional electrophoresis are presented. The most complete distribution of protein fractions was observed in fresh raw minced meat, and when it was exposed to negative temperature, there was a sharp decrease in protein components (carbonic anhydrase 3, αβ-crystallin), as well as a decrease in the staining intensity of protein spots of the main constitutive fractions (tropomyosin alpha 1, myosin light chain 1). In the case of heat treatment, structural muscle proteins were retained with some changes in high molecular weight fractions, namely, protein molecules degraded to compounds with a simpler structure. It was noted that fractions of tropomyosin β-chain, triosephosphate isomerase 1, myosin light chains 2 were not detected after minced meat was frozen, while tropomyosin alpha 1 was retained in all samples.

Distribution of protein fractions in tofu whey wastewater and its potential influence on anaerobic digestion

Wastewater from tofu (soybean curd) production contains a high organic concentration that might pollute the environment if it is not treated properly. Among the major organic constituents of tofu wastewater are proteins. Degradation of proteins generates ammonia and H2S gases, and if this occurs in an anaerobic digester might hamper the digester’s performance. On the other hand, proteins can potentially be recovered as value-added products. This research aimed to identify protein amounts in different fractions of tofu wastewater, as a basis of designing a process to recover the proteins. Furthermore, the influence of a lower protein concentration to anaerobic digestion of tofu wastewater was calculated. Tofu wastewater was fractionated by gravity settlement and filtration into settleable, suspended, and dissolved fractions. Subsequently, total solids, protein, and COD concentrations of each fraction were analysed. Our results show that tofu wastewater contained 2.9 g-protein/L, equivalent to 4 g-COD/L. While most of the proteins were dissolved, 9% of the proteins were settleable. This might be recovered via a settling chamber. Using the protein-separated wastewater in anaerobic digestion might reduce NH3 and H2S by 10% while only reduce biogas production by 2%.

STUDY ON THE BIOLOGICAL VALUE OF PROTEINS WITH HYPOTENSIVE PROPERTIES FROM AIR-DRIED BEEF

The present paper examines an effect of starter culture incorporation into the technology of air-dried beef products on a degree of protein hydration and solubility. The processes of the protein macromolecule hydrolysis on dipeptides, polypeptides and free amino acids are described. It was shown air-dried beef products that contain starter cultures had the high biological value. It was noticed that microorganisms being constituents of starter cultures had the high proteolytic activity and accelerated the biochemical transformation of meat proteins upon curing, which resulted in higher rates of biochemical processes. The molecular weight distribution of protein fractions was determined. The derivatives of meat proteins, peptides, which can have a physiological effect on the body, are the most promising for studying. This study presents an assessment of a protein complex of air-dried beef products made according to different technologies of air drying and shows that the majority of protein spectra in the air-dried beef products with starter cultures are in the zones of proteins with potential hypotensive properties (medium and light zones with molecular weights of 50 kDa — 70 kDa and 5 kDa — 20 kDa, respectively). It is shown that when using the traditional technology of air drying, an accumulation of the protein spectra in meat was observed in the zone of heavy fractions with a molecular weight of 85 кDа — 100 кDа, the medium and light fractions were poorly pronounced. The highest rate of hydrolysis of the air-dried meat products with starter cultures by the enzymes of the gastrointestinal tract makes it possible to predict in a greater degree a level of protein utilization by the human body. It was established that the highest growth indicators were in the laboratory animals, which diet was supplemented with air-dried products that contained starter cultures. A live weight gain over a 30 day period of feeding was 14.37 g and 12.82 g, respectively, in the experimental groups compared to the control groups.

Variations in Protein Concentration and Nitrogen Sources in Different Positions of Grain in Wheat.

The distribution patterns of total protein and protein components in different layers of wheat grain were investigated using the pearling technique, and the sources of different protein components and pearling fractions were identified using 15N isotope tracing methods. It was found that N absorbed from jointing to anthesis (JA) and remobilized to the grain after anthesis was the principal source of grain N, especially in the outer layer. For albumin and globulin, the amount of N absorbed during different stages all showed a decreasing trend from the surface layer to the center part. Whereas, for globulin and glutenin, the N absorbed after anthesis accounted for the main part indicating that for storage protein, the utilization of N assimilated after anthesis is greater than that of the stored N assimilated before anthesis. It is concluded that manipulation of the N application rate during different growth stages could be an effective approach to modulate the distribution of protein fractions in pearled grains for specific end-uses.

Effects of plant density on grain yield, protein size distribution, and breadmaking quality of winter wheat grown under two nitrogen fertilisation rates

Abstract Nitrogen (N) and plant density are two crucial factors that affect winter wheat (Triticum aestivum L.) yield and quality, but little is known regarding the effects of interactions between these two factors on the amount and size distribution of protein fractions and quality traits. We grew the bread wheat cultivar Jinan17 in two successive seasons (2012–2013 and 2013–2014) at three densities of 120 plants m−2 (low), 180 plants m−2 [the usual rate for a multiple-spike cultivar with high tillering ability in the North China Plain (NCP)], and 240 plants m−2 (high) and two levels of N fertilisation of 0 (low N availability treatment without N fertilisation) and 240 kg ha−1 (the usual N rate for winter wheat production in the NCP) to evaluate the effect of N level × plant density interaction on grain yield, grain protein concentration, the amount and composition of protein fractions, dough development time, dough stability time, and loaf volume. The effect of plant density on Jinan 17 grain yield and quality differed between the two N levels. As plant density increased, all the parameters listed above decreased under 0 kg ha−1 N fertilisation, but increased under 240 kg ha−1 N fertilisation. Stepwise regression analysis showed that the dough rheological properties and breadmaking quality of Jinan 17 were affected by plant density under both N levels, primarily through changes in the polymerisation degree of glutenins in the flour.

Complex chemical evaluation of the summer truffle (Tuber aestivum Vittadini) fruit bodies.

Summer truffle ( Tuber aestivum Vittadini) is one of the most important mycorrhizal mushrooms with underground fruit bodies. Formerly the scientific investigations were focused mainly on its specific fragrant constituents. Our work was concentrated on complex chemical characterization including different organic and inorganic components. Summer truffle has middle crude protein, low fat-, and relatively high fiber and chitin contents; its energy level is low. Distribution of protein fractions is characteristic (in % of crude protein): 40.98; 5.91; 3.85; 19.28 and 29.98% for albumins, globulins, prolamins, glutelins and NPN (non protein nitrogen), respectively. We determined soluble oligo- and polysaccharides (9.00 mg/g DM and 49.9 mg/g DM, respectively), as well as the contents of phenoloids and flavonoids (2.8 mg/g DM and 0.093 mg/g DM, respectively). Mineral composition is similar to other mushrooms; four macroelements (K, P, Ca and Mg) give 97.94% of the all mineral content; occurrence of poisonous elements (as As, Cd, V) is not characteristic. Chemical nature of Tuber aestivum (summer truffle) fruit bodies is very characteristic, regarding not only the occurrence of fragrant components but the classical, “usual” components, too. This rare and highly appreciated hypogaeous mycorrhizal fungus belongs to mushrooms of valuable, specific chemical composition.

Split Application of Potassium Improves Yield and End‐Use Quality of Winter Wheat

Many studies have investigated the effects of basal K fertilization on the yield and quality of wheat (Triticum aestivum L.). However, less is known about the influence of the split application of K on yield, size distribution of protein fractions, and quality of wheat. Field studies were conducted in two successive seasons (2010/2011 and 2011/2012) using four winter wheat cultivars, Jimai 20, Gaocheng 8901, Yannong 19, and Jinan 17, and three regimes of K fertilization (K0: no K fertilization; KB: basal K fertilization of 120 kg ha−1; KS: basal K fertilization of 60 kg ha−1 plus topdressing of 60 kg ha−1 at jointing). The yield and its components, protein composition, dough‐mixing properties, and bread‐making quality were determined after harvesting. On average, the KS treatments had a yield advantage over KB treatments mainly resulting from higher kernel weight. The KS treatments improved wheat quality resulted in increased glutenin/gliadin ratio, higher polymerization index (the ratio of sodium dodecyl sulfate to insoluble glutenin in total glutenin), and larger glutenin macropolymer (GMP) particles compared to KB fertilization. No differences in the content of crude protein and wet gluten were found between the KS and KB treatments. Dough development time, stability time, and loaf volume were positively correlated with the glutenin/gliadin ratio, polymerization index, and average size of the GMP, respectively. These results suggest that KS can improve the yield and end‐use quality of winter wheat.

Prediction of protein fractions distribution in wheat (Triticum aestivumL.) mill products

The research was conducted to describe distribution of protein fractions in wheat (Triticum aestivum L.) mill products (semolina, flour and bran) and evaluate the possibility of prediction of protein fractions distribution from values of bread-making quality (protein and gluten content, Zeleny sedimentation volume) evaluated on wholemeal and specific flour. The content of protein fractions was determined by size-exclusion high performance liquid chromatography. Significantly highest glutenin content was found in flour (5.01%). The investigated mill products did not differ in gliadin content, the content of albumin/globulin fraction reached the highest values in bran (3.60%). The model of prediction of glutenin and gliadin content in mill products explained 31–62% and 83–92% of the original variability. The protein fractions distribution in wheat mill products could be satisfactorily predicted from known values of protein and gluten content evaluated on wholemeal and Zeleny sedimentation volume evaluated on specific flour.

A new mutation in the AFP gene responsible for a total absence of alpha feto-protein on second trimester maternal serum screening for Down syndrome

Alpha feto-protein (AFP) is a major plasma protein produced by the yolk sac and the liver during the fetal period. During the second trimester of pregnancy, APF and betahCG serum concentrations are commonly used for screening Down syndrome. AFP deficiency is rare (estimated to be 1/105,000 newborns) and only one sequence alteration has previously been reported in the AFP gene. We report a new mutation in exon 5 of the AFP gene, leading to a total absence of AFP on 2nd-trimester maternal serum screening for Down syndrome, confirmed on the amniotic fluid. Despite this, fetal development and birth were normal. After PCR-amplification, the whole AFP gene was sequenced. The new mutation was a guanine to adenine transition in position 543 creating a premature stop codon in position 181. In order to search for eventual modifications of the amniotic fluid profile, proteins were separated by electrophoresis and compared with 10 normal amniotic fluids sampled at the same developmental age (18 weeks). In the amniotic fluid of our patient albumin rate was reduced whereas alpha1 and beta protein fractions were increased, suggesting that AFP deficiency may modify the distribution of protein fractions. This observation emphasizes the complex molecular mechanisms of compensation of serum protein deficiency. Studies on other families with AFP deficiency are necessary to confirm this observation.

Cu, Fe, Mn and Zn distribution in protein fractions of Brazil-nut, cupuassu seed and coconut pulp by solid-liquid extraction and electrothermal atomic absorption spectrometry

In this work Cu, Fe, Mn and Zn were determined in extracts of Brazil-nut (Bertholletia excelsa), cupuassu (Theobroma grandiflorum) seeds and coconut (Cocos nucifera) pulp, using solid-liquid extraction and electrothermal atomic absorption spectrometry. Different extractant solutions (mixture of methanol and chloroform 1:2 v/v, water, 0.5 mol L-1 NaCl, 70% v/v ethanol, and 0.5 mol L-1 NaOH) were used for extracting lipids, albumins, globulins, prolamins and glutelins, respectively. The protein concentrations determined in Brazil-nut are higher than those observed for cupuassu and coconut pulp. The analysis of lipid fractions reveals high concentations of Fe in Brazil-nut and cupuassu seed and Zn in coconut pulp. For Brazil-nut, these elements are mainly associated to albumin, globulin and glutelin fractions. The same behaviour was not observed for cupuassu seed and coconut pulp. The element concentrations changed in each protein fraction. In general, high concentrations of proteins were determined in NaOH extractants. On the other hand, low concentration of Cu, Fe, Mn and Zn were found in this fraction.

The influence of different nitrogen treatments on the size distribution of protein fractions in hard and soft wheat

The relative quantity of specific proteins, protein subunits, as well as amount and size-distribution of polymeric proteins in wheat kernels may vary due to environmental conditions. In this study, the effect of different nitrogen treatments on polymeric and monomeric proteins in wheat was determined. Two soft white biscuit wheat cultivars, a cracker wheat and a hard red bread wheat were planted under irrigation in a randomized complete block design with three replications in two successive years at six different nitrogen treatments. SE-HPLC was used to determine the amount of monomeric and polymeric proteins, and various quality characteristics were measured after harvesting. The large and small SDS-extractable polymeric proteins were not influenced by different N levels. There was a strong cultivar influence, where some cultivars had a larger reaction to N treatments than others. The later application (at flag leaf stage) of nitrogen did not increase the protein fractions. The total amount of N given seemed to have a greater influence on the protein fractions than the timing of the fertilizer application. The lowest N treatment consistently gave the lowest flour protein content value. There was a strong correlation between flour protein content and large monomeric proteins.

Use of scanning electron microscopy to indicate the similarities and differences in pseudocereal and cereal proteins

SummaryIsolated and separated protein fractions from cereal and pseudocereal grains were analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis and scanning electron microscopy. Prolamin, the main storage protein in cereal such as maize, showed a difference in electrophoretic patterns and fine structure in comparison with those from amaranth and soybean. In contrast glutelins from amaranth, soybean and maize showed some similarity in the distribution of protein bands and in microstructure. Amaranth and soybean were closely similar in distribution of protein fractions and their microscopic structure. As an addition to chemical analyses, microscopy helped to understand and visualize structural changes and textural differences in protein fractions. Pseudocereals can be used as a nutritive substitute of some cereals in functional foods.

Characteristics and in situ degradability of whole crop faba bean, pea, and soybean silages

The objective of this study was to determine the ensiling characteristics and ruminal nutrient degradabilities of faba bean (FS, Vicia faba L.), soybean (SS, Glycine max (L.) Merr.) and pea (PS, Pisum sativum L.) silages. Forages were harvested between the beginning- and full-seed stages and ensiled in mini-silos for 0, 2, 4, 16, and 45 d. Two lactating Holstein cows fitted with ruminal fistulae were used to determine ruminal nutrient degradabilities. Results showed that all silages went through a rapid fermentation as indicated by rapid decline in pH and sharp increase in lactic acid concentration within the first 2 d of ensiling. Extensive proteolysis took place between day 0 and day 4 post-ensiling as indicated by a significant reduction in true protein (TP) and a significant increase in non-protein nitrogen (NPN). During the 45 d of ensiling, TP decreased (P &lt; 0.05) by 26, 31, and 45% while NPN increased (P &lt; 0.05) by 82, 54, and 47% for FS, SS, and PS, respectively. Chemical analysis showed that the three 45-d silages contained a similar level of neutral detergent fiber (NDF, average 421 g kg-1). Crude protein (CP) was highest (P &lt; 0.05) for FS, intermediate for SS, and lowest for PS. Distribution of protein fractions showed that soluble protein and NPN were highest (P &lt; 0.05) for PS, intermediate for SS, and lowest for FS. Neutral (NDICP) and acid (ADICP) detergent insoluble protein levels followed an opposite order to that observed for soluble crude protein (SCP) and NPN. Results of the in situ study showed that SS and PS had a similar ruminal degradability of dry matter (average 68.8%) and CP (82.9%), which were higher (P &lt; 0.05) than those of FS (66.2 and 79.4%, respectively). However, no differences in ruminal degradability of NDF (average 34.7%) were observed between the three legume silages. Key words: Silage, ensiling, forage quality, nutrient degradability