Linkage of in situ ruminal degradation of crude protein with ruminal degradation of amino acids and phytate from different soybean meals in dairy cows.

The objectives of this study were to determine the range in ruminal degradability of crude protein (CP) and intestinal digestibility of rumen undegradable protein in commercial soybean meal (SBM) and to investigate the range in in situ ruminal AA and phytate (InsP6) degradation and their relationship to CP degradation. An in situ study was conducted using 3 lactating Jersey cows with permanent rumen cannulas. Seventeen SBM variants from Europe, Brazil, Argentina, North America, and India were tested for ruminal CP and AA degradation, and in vitro intestinal digestibility of rumen undegradable protein. Nine variants were used to investigate the ruminal degradation of InsP6. The estimated rapidly degradable fraction (a) of CP showed an average value of 4.5% (range: 0.0%-9.0%), the slowly degradable fraction (b) averaged 95% (91%-100%), and the potential degradation was complete for all 17 SBM variants. The degradation of fraction b started after a mean lag phase of 1.7 h (1.1-2.0 h) at an average rate (c) of 10% per hour, but with a high range from 4.5% to 14% per hour. Differences in the degradation parameters induced a considerable range in CP effective degradation at a rumen passage rate of 6% per hour (CPED6) from 38% to 67%; hence, the concentration of rumen undegradable protein varied widely from 33% to 62%. The range in AA degradation between the SBM variants was high, with Ser showing the widest range, from 28% to 96%, and similar for the other AA. The regression equations showed close relationships between CP and AA degradation after 16 h of in situ incubation. However, the slopes of the linear regressions were significantly different between AA, suggesting that degradation among individual AA differs upon a change in CP degradation. The concentrations of InsP6 and myo-inositol pentakisphosphate in bag residues in the in situ study decreased constantly with longer ruminal incubation times. The ruminal degradation parameters of InsP6 ranged from 11% to 37% for fraction a, 63% to 89% for fraction b, and from 7.7% to 21% per hour for degradation rate c, with average values of 21%, 79%, and 16% per hour, respectively. The calculated InsP6 effective degradation at a rumen passage rate of 6% per hour (InsP6ED6) varied from 61% to 84% among the SBM variants. Significant correlations were detected between InsP6ED6 and CPED6 and between InsP6ED6 and chemical protein fractions A, B1, B2, B3, and C. Linear regression equations were developed to predict ruminal InsP6 degradation using CPED6 and chemical protein fractions B3 and C chosen by a stepwise selection procedure. We concluded that a high range in CP, AA, and InsP6 degradation exists among commercial SBM, suggesting that general degradability values may not be precise enough for diet formulation for dairy cows. Degradation of CP in SBM may be used to predict rumen degradation of AA and InsP6 using linear regression equations. Degradation of CP and InsP6 could also be predicted from the chemical protein fractions.

Integrated eco-physiological, biochemical, and molecular biological analyses of selenium fortification mechanism in alfalfa.

MAIN CONCLUSION: Foliar Se (IV) application at 100 mg/kg can act as a positive bio-stimulator of redox, photosynthesis, and nutrient metabolism in alfalfa via phenotypes, nutritional compositions, biochemistry, combined with transcriptome analysis. Selenium (Se) is an essential element for mammals, and plants are the primary source of dietary Se. However, Se usually has dual (beneficial/toxic) effects on the plant itself. Alfalfa (Medicago sativa L.) is one of the most important forage resources in the world due to its high nutritive value. In this study, we have investigated the effects of sodium selenite (Se (IV)) (0, 100, 200, 300, and 500 mg/kg) on eco-physiological, biochemical, and transcriptional mechanisms in alfalfa. The phenotypic and nutritional composition alterations revealed that lower Se (IV) (100 mg/kg) levels positively affected alfalfa; it enhanced the antioxidant activity, which may contribute to redox homeostasis and chloroplast function. At 100 mg/kg Se (IV) concentration, the H2O2, and malondialdehyde (MDA) contents decreased by 36.72% and 22.62%, respectively, whereas the activity of glutathione peroxidase (GPX) increased by 31.10%. Se supplementation at 100 mg/kg increased the plant pigments contents, the light-harvesting capacity of PSII (Fv/Fm) and PSI (ΔP700max), and the carbon fixation efficiency, which was demonstrated by enhanced photosynthesis (37.6%). Furthermore, alfalfa shifted carbon flux to protein synthesis to improve quality at 100 mg/kg of Se (IV) by upregulating carbohydrate and amino acid metabolic genes. On the contrary, at 500 mg/kg, Se (IV) became toxic. Higher Se (IV) disordered the plant antioxidant system, increasing H2O2 and MDA by 14.2 and 4.3%, respectively. Moreover, photosynthesis was inhibited by 20.2%, and more structural substances, such as lignin, were synthesized. These results strongly suggest that Se (IV) at a concentration of 100 mg/kg act as the positive bio-stimulator of redox metabolism, photosynthesis, and nutrient in alfalfa.

Annual protein yield and extractable protein potentials in three legumes and two grasses.

BACKGROUND: New protein sources with low environmental and climatic impact are needed. Perennial crops show advantages as compared to annual crops and the upcoming biorefinery technology can extract proteins from the perennial biomass for protein concentrate production. The search for best-suited biomass crops needs to include harvest during the full growing season to support economic viability of biorefinery plants. Here we examined two grasses under increasing N fertilizer regime (175, 350 and 525 kg N ha-1 ) and three legumes, subject to a four-cut strategy. The well-defined Cornell Net Carbohydrate and Protein System (CNCPS) was used to estimate potential extractable protein. A key, previously presented in the literature, was applied in order to translate the CNCPS results into potential extracted protein concentrate. RESULTS: Crude protein (CP) yield per hectare was highest in red clover in 2015 (2907 kg CP ha-1 ) and the fertilized (525 kg N ha-1 ) tall fescue in 2016 (2435 kg CP ha-1 ). When translating the numbers into potential extraction of protein concentrate, the red clover had the highest protein concentrate yield per hectare in 2015 (835 kg CP ha-1 ) and lucerne in 2016 (803 kg CP ha-1 ). CONCLUSION: The results revealed that the entire season needs attention for optimization and not only the first cut, since both CP yields and quality peaks in different cuts across the five species and 2 years. Further knowledge of CP yield responses to field management and species mixtures are needed in order to advise farmers on the optimal crop for biorefining. © 2021 Society of Chemical Industry.

Dry matter yield, chemical composition and estimated extractable protein of legume and grass species during the spring growth.

BACKGROUND: Knowledge of the variation of extractable protein amount in legumes and grasses as affected by harvest time is important for identifying optimal combinations to enable a high protein production in a biorefinery. The extractability of protein was estimated using the Cornell Net Carbohydrate and Protein System across six harvests during the spring growth. RESULTS: The estimated extractable protein [g kg-1 dry matter (DM)] defined as the easily available fractions B1 +B2 was significantly higher in white clover and lucerne at all harvests while, if the more cell wall attached fraction B3 can be extracted, white clover had the highest extractable protein amongst all species. Total yield of B1 +B2 per ha was higher in white clover and red clover at the early growth while B1 +B2 +B3 was by far the highest for red clover through all harvests. CONCLUSION: White clover could be a good candidate for protein production purpose in a biorefinery due to its high extractable protein content per kg DM. In order to maximise the protein production capacity, harvest should take place during early growth due to a decline in protein extractability with maturity. The final economy of the concept will depend on the value of the fibre after extraction of the protein. © 2017 Society of Chemical Industry.

Nutritional Evaluation of Milk Thistle Meal as a Protein Feedstuff for Diets of Dairy Cattle.

The objective of this work is to investigate the chemical and nutritional value of milk thistle meal (MTM) in order to improve it and to provide theoretical support for its application in dairy cattle production. MTM was assessed in comparison with seven conventional protein feed sources, namely, soybean meal (SBM), cottonseed meal (CS), canola meal (CN), palm kernel meal (PK), rice bran meal (RB), corn germ meal (CG), and sesame meal (SS). The chemical composition of these feedstuffs was assessed using wet chemical analysis, the Cornell Net Carbohydrate and Protein System was used to evaluate the carbohydrate and protein fractions, and the in situ nylon bag technique and the modified three-step in vitro method were used to assess the rumen degradation and intestinal digestibility. Additionally, Fourier transform infrared technology was used to determine the feedstuff protein spectral molecular structure and its amino acid profile was also assessed. The result showed that MTM acid detergent fiber, lignin, unavailable nitrogen, and non-degradable carbohydrate content were higher than those of the other feedstuffs. It had a 17% and 36% rumen effective degradation rate of neutral detergent fiber and dry matter, respectively, and had the lowest small intestinal rumen undegradable protein digestibility rate. It was low in leucine, histidine, arginine, and proline, but high in methionine. The total area of amide I and amide II in the protein secondary structure was similar to that of CN and CS, and the amide I and II ratio was not different from that of RB. To sum up, MTM has a poor carbohydrate composition and is high in fiber but, in comparison to most other protein feeds, has a higher crude protein rumen effective degradation rate, similar to that of SBM, and it is a good source of methionine, a limiting amino acid. Hence, its nutritional value can be further improved for application in dairy feeding through processes such as microbial or enzymatic fermentation.

Relationship between the Methane Production and the CNCPS Carbohydrate Fractions of Rations with Various Concentrate/roughage Ratios Evaluated Using In vitro Incubation Technique.

The objective of the trial was to study the relationship between the methane (CH4) production and the Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate fractions of feeds for cattle and the suitability of CNCPS carbohydrate fractions as the dietary variables in modeling the CH4 production in rumen fermentation. Forty-five rations for cattle with the concentrate/roughage ratios of 10:90, 20:80, 30:70, 40:60, and 50:50 were formulated as feed samples. The Menke and Steingass's gas test was used for the measurement of CH4 production. The feed samples were incubated for 48 h and the CH4 production was analyzed using gas chromatography. Statistical analysis indicated that the CH4 production (mL) was closely correlated with the CNCPS carbohydrate fractions (g), i.e. CA (sugars); CB1 (starch and pectin); CB2 (available cell wall) in a multiple linear pattern: CH4 = (89.16±14.93) CA+ (124.10±13.90) CB1+(30.58±11.72) CB2+(3.28±7.19), R(2) = 0.81, p<0.0001, n = 45. Validation of the model using 10 rations indicated that the CH4 production of the rations for cattle could accurately be predicted based on the CNCPS carbohydrate fractions. The trial indicated that the CNCPS carbohydrate fractions CA, CB1 and CB2 were suitable dietary variables for predicting the CH4 production in rumen fermentation in vitro.

Optimizing corn silage quality during hot summer conditions of the tropics: investigating the effect of additives on in-silo fermentation characteristics, nutrient profiles, digestibility and post-ensiling stability.

Corn crop grown and ensiled at high temperature have lower water soluble carbohydrates (WSC), epiphytic lactic acid bacteria (LAB) population, lactic acid concentration, fermentation quality and aerobic stability. This study systematically investigated the effects of heterofermentative LAB (hetLAB), homofermentative LAB (homLAB), molasses and their mixture (MIX) on in-silo fermentation characteristics, chemical profiles, Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate subfractions, in vitro digestibility (DMD), microbial count, and post-ensiling aerobic stability of whole crop corn silage during hot summer (30 to 45°C) condition. Corn hybrids (P30K08 and DK6789) were ensiled at targeted dry matter (DM) of 330 g/kg for 0, 3, 7, 21, and 150 days in 3 L silos, without additive (CCS) or treated with hetLAB (4×106 cfu/g Lactobacillus buchneri), homLAB (1×106 cfu/g of L. plantarum), molasses (3% of fresh forage) or MIX (half of individual doses of homLAB, hetLAB and molasses) additives. The CCS, homLAB, hetLAB, molasses, or MIX treated chopped material of each hybrid were ensiled in 16 replicate silos at a density of 260 kg of DM/m3. Compared to CCS, the additives significantly improved silage nutritional and fermentation quality, DM digestibility (in vitro), count of LAB, DM recovery and aerobic stability, and decreased counts of yeast and mold. Among the inoculants, the homLAB and MIX inoculated silages had greatest improvement in fermentation quality and nutritional value. The homLAB produced corn silage with the highest (P < 0.05) content of lactic acid, and soluble carbohydrates, and lowest contents of acetic acid, NH3-N and pH, demonstrating desirable and restricted in silo fermentation. On the other hand, the hetLAB inoculated silages had the greatest (P < 0.05) value of acetic acids, highlighting greater aerobic stability. Interestingly, the MIX silages followed the hetLAB in acetic acid value and homLAB in lactic acid value. Notably, without additive stable pH was not achieved during 21 days, with application of molasses, hetLAB and the MIX inoculants stable pH was achieved during 7 days, and with homLAB stable pH was achieved during the first 3 days of ensiling. The greatest numbers of viable LAB were recorded in homLAB (8.13 log cfu/g) and MIX (7.89 log cfu/g) inoculated silages, while the lowest for CCS (6.29 log cfu/g). The lowest yeast (1.48 log cfu/g) and mold (0.22 log cfu/g) were recorded for hetLAB inoculated silage. The greatest (P < 0.05) DM recovery was recorded for hetLAB (97.3%) and MIX (96.9%), and the lowest for the control silage (92.9%). All additives significantly improved the aerobic stability of corn silage, and the greatest value of >72 h was recorded for hetLAB and MIX inoculats, and the lowest for CSC (25 h). In conclusion, additives application can improve fermentation quality, nutritional value, DM recovery and aerobic stability of whole crop corn silage under hot summer conditions of the tropics. The MIX inoculant showed potential to improve in-silo fermentation, and aerobic stability at the same time, however, further investigation are required, particularly with respect of dose rate.

Linking Protein Quality in Biorefinery Output to Forage Crop Crude Protein Input via the Cornell Net Carbohydrate and Protein System.

The biorefinery technology aiming at protein extraction is rising and identification of suitable plant biomass input with valuable protein compounds for extraction is needed. Forage crops have been evaluated by the Cornell Net Carbohydrate and Protein System (CNCPS), and the result used as proxy of extractable protein in a biorefinery process. This serves as a helpful link between crop production and refinery output; however, the method has never been validated. Such validation is the main aim of this study. Five forage species-white clover, red clover, lucerne, perennial ryegrass, and tall fescue-were cut at four dates during spring and processed in a lab-scale refinery (screw press and subsequent protein precipitation from the green juice). The pulp fraction and the precipitated protein concentrate were both CNCPS analyzed to follow the initial crude protein (CP) plant input into these two fractions. Total recovery in concentrate was highest for the legumes, which points to an advantage of these species in protein extraction setups. High recovery of B1 and B2 (50% or higher for the grasses) in the pulp demonstrated a large proportion of soluble protein ending up in the fibrous pulp and shed light on the reason behind high feed quality of the pulp fraction. In conclusion, the existing tentative assumption of extractable protein being equal to CNCPS fractions of B1 and B2 and partly B3 was shown to be too simplified. The presented findings can improve crop species screening in terms of expected extractable protein yield.

Effects of Malic Acid and Sucrose on the Fermentation Parameters, CNCPS Nitrogen Fractions, and Bacterial Community of Moringa oleifera Leaves Silage.

The present study investigated the effects of malic acid, sucrose, and their mixture on the fermentation parameters, Cornell Net Carbohydrate and Protein System (CNCPS) nitrogen fractions, and bacterial community of Moringa oleifera leaves (MOL) silages. The trial was divided into four treatments and labeled as CON (control group) and MLA, SUC, and MIX (respectively denoting the addition of 1% malic acid, 1% sucrose, and 1% malic acid + 1% sucrose to the fresh weight basis). The silage packages were opened on the 2nd, 5th, 10th, 20th, and 40th days of ensiling for subsequent determination. Malic acid and sucrose increased the lactic acid content (p < 0.05) and pH value, and the acetic acid contents of MLA and MIX were lower than those in CON (p < 0.05). Compared with sucrose, malic acid had a better capacity to preserve nutrients and inhibit proteolysis, and thus exerted better effects on the CNCPS nitrogen fractions. The results of 16S rRNA showed that the dominant phyla were Firmicutes and Proteobacteria and that the dominant genera were Lactobacillus and Weissella. With the application of silage additives and the processing of fermentation, there was a remarkable change in the composition and function of the bacterial community. The variation of the fermentation parameters and CNCPS nitrogen fractions in the MOL silages caused by malic acid and sucrose might be attributed to the dynamic and dramatic changes of the bacterial community.

Steam Explosion Treatment of Byproduct Feedstuffs for Potential Use as Ruminant Feed.

Although many byproducts of milling industries have potential as a ruminant feed, they have not been widely used due to their low nutritive value, especially high-fiber content and difficult processing techniques. Steam explosion can increase the degradation of hemicellulose, cellulose and lignin and make byproduct feedstuffs more suitable as ruminant feed. Five byproduct feedstuffs: cassava alcohol residue (CAR), distillers' grains (DG), cottonseed meal (CM), rapeseed meal (RM) and potato starchy residues (PSR), were steam-exploded using five different processing parameters and the effects on the chemical composition, in vitro digestibility, energy value, and Cornell Net Carbohydrate and Protein System composition were assessed in order to provide a theoretical basis for the technique's development and utilization for ruminant feed production. In this study, after steam-explosion treatment, the nutritive value and in vitro dry matter digestibility (IVDMD) of CAR, DG, RM and PSR were improved (p < 0.05), while there was no effect on nutritive value of CM (p > 0.05). Specifically, steam explosion treatment decreased the contents of neutral detergent fiber, acid detergent fiber, available cell wall, and slowly degraded protein, and increased the total digestible nutrients, digestible energy, metabolic energy, net energy for maintenance, and net energy for gain, sugar, non-structural carbohydrate and IVDMD. Therefore, steam-explosion treatment offers the potential to improve the suitability of byproduct feedstuffs as ruminant feed.

Vibrational spectroscopic study on feed molecular structure properties of oil-seeds and co-products from Canadian and Chinese bio-processing and relationship with protein and carbohydrate degradation fractions in ruminant systems.

The objective of this study was to apply ATR-FTIR spectroscopy to reveal feed molecular structure properties of oil-seeds and co-products and relationship with protein and carbohydrate degradation fractions in ruminant systems. The oil-seeds and co-products were from both various bio-processing industries in Canada and China. The protein and carbohydrate degradation fractions were evaluated with updated CNCPS system. Results showed that in the co-products from canola processing industries there are strong relationship between 1) soluble true protein (PA2) fraction and the following protein molecular structure spectral characteristics; spectral peak area of amide I and amide II (r = 0.56, P = 0.001), area of amide I (r = 0.67, P < 0.001), height of amide I (r = 0.74, P < 0.001), amide I and II ratio (r = 0.57, P = 0.001), α-helix (r = 0.82, P < 0.001), and ß-sheet (r = 0.61, P < 0.001), 2) slowly degradable true protein (PB2) fraction and height of amide I (r = -0.60, P = 0.001), α-helix (r = -0.72, P < 0.001), and ß-sheet (r = -0.51, P = 0.004), 3) soluble fiber (CB2) fraction and α-helix and ß-sheet height ratio (r = -0.63, P < 0.001), and 4) unavailable NDF (CC) fraction and height of amide I (r = 0.55, P = 0.002). These results indicated feed molecular structure spectral properties of the oil-seeds and co-products related to CNCPS protein and carbohydrate degradation fractions in ruminant systems.

High Fiber Cakes from Mediterranean Multipurpose Oilseeds as Protein Sources for Ruminants.

Fifteen oilseed cakes from sunflower, pomegranate, cardoon, tobacco and hemp were characterized with regard to chemical composition, Cornell Net Carbohydrate and Protein System (CNCPS) fractionation, in vitro digestibility of dry matter, neutral detergent fiber, and crude protein. All the cakes presented low moisture, rather variable ether extract contents and medium to high levels of crude protein and neutral detergent fiber. The cakes significantly differed in terms of CNCPS partitioning and in vitro digestibility. Tobacco and hemp cakes presented high contents of slow degradable fractions of crude protein and carbohydrate joined to good post-ruminal protein digestibility. Cardoon cakes presented the highest rumen protein degradability. Based on crude protein content and intestinal digestibility of rumen undegraded protein, cakes of tobacco and hemp showed the better potential as alternative protein supplements for ruminants, while pomegranate appears to be the least suitable for ruminant feeding.

Relationship of carbohydrates and lignin molecular structure spectral profiles to nutrient profile in newly developed oats cultivars and barley grain.

The objectives of this study were to quantify the chemical profile and the magnitude of differences in the oat and barley grain varieties developed by Crop Development Centre (CDC) in terms of Cornell Net Carbohydrate Protein System (CNCPS) carbohydrate sub-fractions: CA4 (sugars), CB1 (starch), CB2 (soluble fibre), CB3 (available neutral detergent fibre - NDF), and CC (unavailable carbohydrate); to estimate the energy values; to detect the lignin and carbohydrate (CHO) molecular structure profiles in CDC Nasser and CDC Seabiscuit oat and CDC Meredith barley grains by using Fourier transform infrared attenuated total reflectance (FTIR-ATR); to develop a model to predict nutrient supply based on CHO molecular profile. Results showed that NDF, ADF and CHO were greater (P<0.05) in oat than in barley. The starch content was greater (P<0.05) in barley than in oat. The CDC Meredith showed greater total rumen degradable carbohydrate (RDC), intestinal digestible fraction carbohydrate (FC) and lower total rumen undegradable carbohydrate (RUC). However, the estimated milk production did not differ for CDC Nasser oat and CDC Meredith barley. Lignin peak area and peak height did not differ (P>0.05) for oat and barley grains as well as non-structural CHO. However, cellulosic compounds peak area and height were greater (P<0.05) in oat than barley grains. Multiple regressions were determined to predict nutrient supply by using lignin and CHO molecular profiles. It was concluded that although there were some differences between oat and barley grains, CDC Nasser and CDC Meredith presented similarities related to chemical and molecular profiles, indicating that CDC Meredith barley could be replaced for CDC Nasser as ruminant feed. The FTIR was able to identify functional groups related to CHO molecular spectral in oat and barley grains and FTIR-ATR results could be used to predict nutrient supply in ruminant livestock systems.

Effects of TT8 and HB12 Silencing on the Relations between the Molecular Structures of Alfalfa ( Medicago sativa) Plants and Their Nutritional Profiles and In Vitro Gas Production.

The objective of this study was to investigate the effects of silencing the TT8 and HB12 genes on the nutritive profiles and in vitro gas production of alfalfa in relation to the spectral molecular structures of alfalfa. TT8-silenced (TT8i, n = 5) and HB12-silenced (HB12i, n = 11) alfalfa were generated by RNA interference (RNAi) and grown with nontransgenic wild type controls (WT, n = 4) in a greenhouse. Alfalfa plants were harvested at early-to-mid vegetative stage. Samples were analyzed for their chemical compositions, CNCPS fractions, and in vitro gas production. Correlations and regressions of the nutritional profiles and in vitro gas production with the molecular spectral structures were also determined. The results showed that the transformed alfalfa had higher digestible fiber and lower crude protein with higher proportions of indigestible protein than WT. HB12 RNAi had lower gas production compared with those of the others. Some chemical, CNCPS, and gas-production profiles were closely correlated with spectral structures and could be well predicted from spectral parameters. In conclusion, the RNAi silencing of TT8 and HB12 in alfalfa altered the chemical, CNCPS and gas-production profiles of alfalfa, and such alterations were closely correlated with the inherent spectral structures of alfalfa.

Association of Bio-energy Processing-Induced Protein Molecular Structure Changes with CNCPS-Based Protein Degradation and Digestion of Co-products in Dairy Cows.

The primary objective of this study was to develop a model to predict Cornell Net Carbohydrate Protein System (CNCPS) protein degradation and digestion based on protein molecular structure changes induced by bio-energy processing in different types of co-products (CoPR, CoPC, CoPS = co-products from bioprocessing of rapeseed, canola seed, and soybean, respectively). The results showed that the inherent structure changes induced by the processing had a close relationship with CNCPS predicted protein degradable, undegradable, and digestible contents. The amide I to II ratio and α-helix to ß-sheet ratio could be used to predict total degradable protein (R(2) = 0.99, RSD = 0.84, P < 0.001). Total CNCPS intestinal digestible protein could be predicted by protein structure α-helix to ß-sheet ratio (R(2) = 0.93, RSD = 0.33, P < 0.001). In conclusion, the processing-induced protein molecular structure changes were highly linked to protein nutritive value of the co-products and could be used as predictors for CNCPS protein degradation and digestion in dairy cattle.

Non-destructive analysis of the conformational differences among feedstock sources and their corresponding co-products from bioethanol production with molecular spectroscopy.

The objective of this study was to determine the possibility of using molecular spectroscopy with multivariate technique as a fast method to detect the source effects among original feedstock sources of wheat and their corresponding co-products, wheat DDGS, from bioethanol production. Different sources of the bioethanol feedstock and their corresponding bioethanol co-products, three samples per source, were collected from the same newly-built bioethanol plant with current bioethanol processing technology. Multivariate molecular spectral analyses were carried out using agglomerative hierarchical cluster analysis (AHCA) and principal component analysis (PCA). The molecular spectral data of different feedstock sources and their corresponding co-products were compared at four different regions of ca. 1800-1725 cm(-1) (carbonyl CO ester, mainly related to lipid structure conformation), ca. 1725-1482 cm(-1) (amide I and amide II region mainly related to protein structure conformation), ca. 1482-1180 cm(-1) (mainly associated with structural carbohydrate) and ca. 1180-800 cm(-1) (mainly related to carbohydrates) in complex plant-based system. The results showed that the molecular spectroscopy with multivariate technique could reveal the structural differences among the bioethanol feedstock sources and among their corresponding co-products. The AHCA and PCA analyses were able to distinguish the molecular structure differences associated with chemical functional groups among the different sources of the feedstock and their corresponding co-products. The molecular spectral differences indicated the differences in functional, biomolecular and biopolymer groups which were confirmed by wet chemical analysis. These biomolecular and biopolymer structural differences were associated with chemical and nutrient profiles and nutrient utilization and availability. Molecular spectral analyses had the potential to identify molecular structure difference among bioethanol feedstock sources and their corresponding co-products.

In vitro degradation kinetics of protein and carbohydrate fractions of selected tropical forages / Cinética de degradação in vitro das frações de proteína e carboidrato em forrageiras tropicais

Whereas obtain detailed information about nutrient composition and degradation rates of carbohydrate and protein fractions of tropical forages is essential to determine how much of each nutrient can be used by the animal and the main limiting causes to the level of production. A descriptive study was conducted to evaluate the degradation rate of protein and carbohydrate fractions and understand degradation synchronism of carbohydrates and protein fraction in the rumen of goats fed Tifton 85, mulberry and leucaena forages. Contents of crude protein (CP), nonprotein nitrogen (NPN), neutral detergent insoluble nitrogen (NDIN) and acid detergent insoluble nitrogen (ADIN) were measured to obtain the protein fractions A, B1, B2 and C. Degradation profiles of nitrogen fractions were obtained in vitro incubating the forages samples with proteases from Streptomyces griseus. Contents of sugars, starch and soluble fiber (neutral detergent NDSF) were analyzed to determine the fractions A and B1 from total carbohydrates (TC), whereas for fraction B2, C and degradation rate of fraction B2, the gravimetric technique of in vitro degradation of the fiber was used through kinetic interpretation of degradation profiles. It was adopted descriptive statistics to summarize the dataset, to describe the data, tables were compiled and used sample average as position measurement. Regarding Tifton 85, the sum of fractions A and B1 was 51.61 g/100g CP and the fraction B2 was 38.74 g/100g CP. Thus, the portion of slowly degradable protein from this forage is higher and tends to escape from rumen contributing with amino acids in the small intestine. Differently, most of the protein from mulberry and leucaena are present as highly degradable protein in rumen (B1), requiring supplementation with readily fermentable carbohydrate for a better utilization of nitrogen compounds. Considering the partitions of protein in different compartments of the plant, possibly the mixture between forages promotes a better balance for the use of this nutrient by animals. Fractions representing about 80g/100g of the protein from Tifton 85 presents problems to be used by animals. This means that, despite the high levels of protein in Tifton 85, metabolizable protein deficit may occur at any time after the intake of forages by the animals. Mulberry and leucaena are extremely degradable feed, both for cellular content and cell wall, with high possibility of presenting good synchronization between degradation of carbohydrate and protein.

A obtenção de informações detalhadas sobre a composição dos nutrientes e a taxa de degradação das frações de carboidratos e proteínas é essencial para determinar quanto de cada nutriente pode ser usado pelo animal e quais as principais limitações para o nível de produção. Um estudo descritivo foi conduzido para avaliar a taxa de degradação das frações de carboidratos e proteína e compreender o sincronismo de degradação dessas frações no rúmen de cabras alimentadas com as forrageiras Tifton-85, amoreira e leucena. Os conteúdos de proteína bruta (PB), nitrogênio não protéico (NNP), nitrogênio insolúvel em detergente neutro (NIDN) e nitrogênio insolúvel em detergente ácido (NIDA) foram mensurados para obter as frações de protéicas A, B1, B2 e C. O perfil de degradação das frações de nitrogênio foram obtidas por incubação das forragens com proteases de Streptomyces griseus. Os conteúdos de açúcares, amido e fibra solúvel em detergente neutro (FSDN) foram analisados para determinar as frações A e B1 dos carboidratos totais (CT), sendo que para obtenção da fração B2, C e para taxa de degradação da fração B2, a técnica gravimétrica de degradação da fibra in vitro foi utilizada através da interpretação do perfil cinético de degradação. Foi utilizada a estatística descritiva para analisar os dados e como medida de posição foi adotada a média. Em relação ao Tifton 85, a soma das frações A e B1 foram 51.61 g/100g PB e a fração B2 foi 51.61 g/100g PB. Portanto, as frações de proteína de baixa degradação dessa forrageira são altas e tendem a escapar do rúmen e contribuir com aminoácidos no intestino delgado. Por outro lado, a maior parte da proteína da amoreira e leucena são altamente degradáveis no rúmen (B1), o que requer suplementação com carboidratos rapidamente fermentáveis para melhor utilização dos compostos nitrogenados. Considerando as partições da proteína nas diferentes partes da planta, é possível que a mistura entre essas forrageiras permita um melhor balanceamento para uso desse nutriente pelos animais. Cerca de 80g/100g de proteína do Tifton 85 apresentaram problemas de uso pelos animais. Isso significa que, apesar do alto nível de proteína nessa forrageira, deficiência de proteína metabolizável pode ocorrer em algum momento. Amoreira a leucena são alimentos com alta degradação, tanto do conteúdo celular como da parede celular, com alta possibilidade de apresentar boa sincronização entre a degradação de carboidratos e proteína.

Evaluación del modelo CNCPS-S para predecir el crecimiento del borrego pelibuey / Evaluation of the CNCPS-S model to predict the pelibuey sheep growth

Se evaluó el modelo de carbohidratos y proteínas netas de la Universidad de Cornell para ovinos (CNCPS-S), en cuanto a su capacidad para predecir la ganancia de peso vivo y el consumo de alimento en ovinos de pelo. Se utilizó una base de datos con información procedente de 29 experimentos, con un total de 1189 ovinos Pelibuey y 93 dietas. Los datos se agruparon por sexo y se analizó la capacidad predictiva del modelo considerando como principales indicadores los coeficientes de correlación (r) y de regresión lineal (r²), el error estándar de la estimación (MSE), el coeficiente de concordancia de la correlación (Cb y Pc), la media mínimo cuadrática del error de la predicción (MSEP) la eficiencia del modelo (MEF), y el coeficiente de determinación del modelo (CD). La predicción de la ganancia e peso vivo fue subestimada por el modelo. La r, r² y el Cb fueron mayores en las hembras que en los machos, con valores de 0.84; 0.71; 0.87; y 0.69; 0.48; 0.79, respectivamente, los valores de MEF indican una mayor eficiencia para los machos que en las hembras con valores de -0.004 y 0.443, respectivamente; el MSE fue menor en las hembras que en los machos, a igual que la MSEP y el CD, éste último cercano a la unidad, indicando una mejor predicción del modelo. Se concluye que el CNCPS-S fue más exacto en hembras pero más preciso en machos para predecir la ganancia de peso vivo en ovinos Puelibuey. La evaluación del modelo sugiere que el CNCPS-S puede emplearse para predecir la ganancia de peso en ovinos Puelibuey, sin embargo es necesario hacer adecuaciones para mejorar su capacidad de predicción en esta raza.

The Cornell Net Carbohydrate and protein System for sheep (CNCPS-S) was evaluated on its prediction capacity for daily weight gain and food intake of hair sheep. A data base containing information from 29 experiments, 1189 Pelibuey sheep and 93 diets was utilized. Data were grouped by sex, model adequacy was analyzed using correlation and lineal regression analysis (r and r2), the mean square error or standard error of the estimate (MSE), the concordance correlation coefficient (CCC, “Cb y Pc “), the mean square error of prediction (MSEP), the model efficiency (MEF), and the determination coefficient of the model (CD). Daily gain prediction was sub estimated by the model. The r, r2 and Cb were higher in females than males with values of 0.84, 0.71, 0.87, 0.48, y 0.69, 0.79, respectively, the MEF values indicated a better efficiency with males as compared with females with values of -0.004 y 0.443, respectively; ewes have lower MSE than males, similarly MSEP and CD, the last one closer to the unity, indicated a better prediction by the model. It was concluded that the CNCPS-S model was more accurate for females and more precise for males. The evaluation of the model indicated that the CNCPS-S can be used for predicting daily gain on hair sheep, however some adjustments are needed in order to improve the estimations with hair sheep.