Fractional Degradation Rate Research Articles

Effects of Sprouted Barley with Different Cultivation Stages on Fermentation Characteristics and Degradation Kinetics in the Rumen

The present study investigated the effects of sprouted barley (SB) with different cultivation stages on fermentation characteristics and degradation kinetics in the rumen. The SB was cultivated in three different stages as follows: 0, 4, and 8 days. Dried samples from each cultivation stage of SB were incubated in the rumen buffer at 39 °C for 48 h in quadruplicate with three blanks. Dry matter (DM) and neutral detergent soluble carbohydrate concentrations of SB decreased linearly (p = 0.001) by increasing the cultivation stage, while crude protein, neutral detergent fiber (NDF), acid detergent fiber, and hemicellulose concentrations increased linearly (p ≤ 0.001). Total volatile fatty acid and butyrate in the rumen decreased linearly (p ≤ 0.020) by increasing the cultivation stage, while pH and propionate increased linearly (p < 0.001). The total degradation fraction of DM and NDF increased quadratically (p ≤ 0.003). The fraction degradation rate of DM and NDF decreased linearly (p ≤ 0.001) by increasing the cultivation stage, while the lag phase increased linearly (p ≤ 0.010). The present study concluded that cultivated SB at 4 days was recommended for animal feed due to the highest nutrient degradation in the rumen without any adverse effects on fermentation characteristics.

Effect of Tannin Inclusion on the Enhancement of Rumen Undegradable Protein of Different Protein Sources

Tannins can be utilized to increase rumen undegradable protein (RUP) by their capacity to form complexes with diverse nutrients present in the feed. In that regard, high-performance ruminants demand elevated RUP levels. The objective of this study was to evaluate the effects of incorporating varying levels of tannin into three protein sources (cottonseed, peanut, and soybean meals) on ruminal kinetic parameters, ruminal fermentation, and intestinal digestibility. Thus, three in situ experiments were conducted to investigate the ruminal degradation kinetics, where Fraction A represents the soluble portion, Fraction B relates to the portion potentially degraded in the rumen, and kd denotes the degradation rate of Fraction B, for both dry matter (DM) and crude protein (CP) in the rumen. Additionally, the study assessed dry matter effective degradability (ED), rumen undegradable protein (RUP), and intestinal digestibility (ID). These experiments utilized three cannulated animals for the in situ incubations. Regarding cottonseed meal in terms of DM degradation kinetics, tannin inclusion had a quadratic effect on fraction A (p < 0.01), B (p = 0.10, trend), kd (p = 0.03), and ED (p < 0.01). Fraction A of CP had a cubic effect (p = 0.03), being greater for the control compared with the other treatments. The inclusion of tannin linearly increased RUP (p < 0.01). The RUP proportion increased 29, 33, and 45% when 20, 40, and 60 g/kg tannin were used, respectively, compared to the control. For peanut meal, the A fraction of protein and RUP responded quadratically as tannin was included in peanut meal (p < 0.01). However, tannin levels did not affect fraction B of protein and ID. Regarding soybean meal, fractions A and B of DM and ED had cubic effects (p < 0.01), being greater for the control compared with the other treatments, and responded quadratically as tannin increased. Also, tannin inclusion had a cubic effect on fractions A and B of protein, RUP, and ID (p < 0.01). The cubic behavior showed greater B fraction and ID and lower A fraction and RUP for the control compared other treatments (p < 0.01). Tannins offer a promising avenue for elevating RUP levels in diets featuring cottonseed and peanut meals. Nevertheless, no advantages were observed when treating soybean meal with tannin.

Comparative evaluation of nutrient composition, in vitro nutritional value, and antioxidant activity of de-oiled meals from walnut, hazelnut, almond, and sesame.

This study aimed to establish a comparative database on the chemical composition, in vitro nutritional value, and antioxidant activity of the de-oiled meals produced from walnut, hazelnut, almond, and sesame seeds from the ruminant nutrition perspective. The meals were provided in dried form after their oil harvest using the cold-pressing oil extraction method. Crude protein (CP) constituted the major component of the meals and was the greatest in walnut and almond (average of 45.6% of dry matter (DM)], intermediate in hazelnut meal (41.4%), and least in sesame meal (33.3%)). Potassium was the most abundant mineral in walnut, hazelnut, and almond meals, followed by phosphorus, calcium, and magnesium. The CP fractions determined using the Cornell Net Carbohydrate and Protein System were largely different across the meals, with fraction A being the greatest in hazelnut (40.9% of CP) and intermediate in almond, sesame, and walnut meals (11.4% of CP). The unavailable CP fraction (fraction C) was the least abundant fraction in all meals, ranging from 0.13% of CP in walnut to 3.30% of CP in hazelnut meal. Oleic and linoleic acids were the predominant unsaturated fatty acids, and palmitic acid was the principal fatty acid in all meals analyzed. The fractional degradation rate (h-1) ranged from 0.043 in almond meal to 0.017 in walnut meal. In vitro intestinal CP digestibility (% of rumen-undegraded protein) ranged from 91.6 in hazelnut meal to 97.2 in almond meal. Total phenolics expressed as milligram tannic acid equivalent/gram DM was greatest in walnut meal (11.9), resulting in the greatest antioxidant activity recorded for walnut meal (83.2%). This study provided a database on the nutrient composition, in vitro nutritional value, and antioxidant capacity of the selected de-oiled meals. Additional investigation is needed to identify the in vivo response of their inclusion in the diet of ruminants.

Effect of drought stress on neutral detergent fiber degradation kinetics of corn for silage

The objective of this study was to determine the effect of irrigation on in situ neutral detergent fiber (NDF) degradability of corn tissues from plants grown under controlled conditions in a greenhouse. Five commercial corn hybrids were planted in 6 pots that were placed in a greenhouse. Pots were randomly subjected to 2 irrigation regimens, which consisted of either abundant (A; 598 mm) or restricted (R; 273 mm) irrigation. At harvesting, leaf blades and stem internodes were collected from the upper and bottom portion of the plants. Tissue samples were incubated in the rumen of 3 rumen-cannulated cows for 0, 3, 6, 12, 24, 48, 96, and 240 h to determine in situ NDF degradation kinetics. Drought stress did not affect the concentration of undegraded NDF (uNDF) in upper or bottom internodes but slightly decreased it in upper leaf blades (17.5 and 15.7% for A and R, respectively). The concentration of uNDF differed substantially among corn hybrids in upper internodes (13.4 to 28.3% uNDF), bottom internodes (21.5 to 42.3% uNDF), and upper leaf blades (11.6 to 20.1% uNDF). No interactions existed between irrigation treatment and corn hybrid for uNDF concentration. Drought stress did not affect the fractional degradation rate (kd) of NDF in upper internodes, bottom internodes, or upper leaf blades. The kd of NDF differed among corn hybrids in upper (3.8 to 6.6%/h) and bottom internodes (4.2 to 6.7%/h) but did not vary in upper leaf blades (3.8%/h). No interactions existed between irrigation treatment and corn hybrids for the kd of NDF. Significant interactions existed between irrigation treatment and corn hybrids for the effective ruminal degradation (ERD) of NDF in upper and bottom internodes. This interaction did not exist for upper leaf blades. The ERD of NDF differed substantially among corn hybrids in upper leaf blades (32.5 to 39.1%). In conclusion, drought-stressed corn had a marginal increase of NDF degradability of leaf blades but not in stem internodes, and drought stress had no effects on ERD of NDF. The effect of drought stress on NDF degradability of corn for silage is still inconclusive and deserves further investigation.

Use of Heating Methods and Xylose to Increase Rumen Undegradable Protein of Alternative Protein Sources: 1) Peanut Meal

Peanut meal has an excellent total protein content but also has low rumen undegradable protein (RUP). High-performance ruminants have high RUP requirements. We aimed to evaluate the effects of processing peanut meal with an autoclave and conventional and microwave ovens, with and without using xylose on its ruminal kinetics degradation parameters and intestinal digestibility (ID). In situ studies were conducted to determine dry matter (DM) and crude protein (CP) rumen degradation kinetics. In vitro studies were conducted to evaluate intestinal digestibility (ID). The control treatment had a greater fraction A for DM and CP than peanut meals processed with an autoclave or conventional oven. The control had greater kd for CP compared with the microwave. The addition of xylose decreased fraction A, the degradation rate of fraction B (kd) and RUP, and increased the protein B fraction of autoclaved peanut meal. We observed a decrease in effective degradability (ED) and increased RUP for processed treatments in all experiments compared with the control. Processing methods did not affect the protein ID of autoclaved peanut meal compared to the control. An interaction between xylose and heating time was observed, where increasing heating time linearly reduced the ID of xylose-untreated treatments. Overall, these results suggest that the tested methods effectively increased the RUP content of peanut meal.

Meta-analysis of apparent ruminal synthesis and postruminal flow of B vitamins in dairy cows.

As milk production has significantly increased over the past decade(s), existing estimates of the B-vitamin needs of the modern dairy cow are currently being reconsidered, as suboptimal B-vitamin supply may affect metabolic efficiency. At the same time, however, "true" (i.e., biologically active forms, excluding nonfunctional analogs) B-vitamin supply also cannot be adequately estimated by dietary intake, as the rumen microbiota has been shown to play a significant role in synthesis and utilization of B vitamins. Given their complex impact on the metabolism of dairy cows, incorporating these key nutrients into the next generation of mathematical models could help to better predict animal production and performance. Therefore, the purpose of this study was to generate hypotheses of regulation in the absence of supplemental B vitamins by creating empirical models, through a meta-analysis, to describe true B-vitamin supply to the cow (postruminal flow, PRF) and apparent ruminal synthesis (ARS). The database used for this meta-analysis consisted of 340 individual cow observations from 15 studies with 16 experiments, where diet and postruminal digesta samples were (post hoc) analyzed for content of B vitamins (B1, B2, B3, B6, B9, B12). Equations of univariate and multivariate linear form were considered. Models describing ARS considered dry matter intake (DMI, kg/d), B-vitamin dietary concentration [mg/kg of dry matter (DM)] and rumen-level variables such as rumen digestible neutral detergent fiber (NDF) and starch (g/kg of DM), total volatile fatty acids (VFA, mM), acetate, propionate, butyrate, and valerate molar proportions (% of VFA), mean pH, and fractional rates of degradation of NDF and starch (%/h). Models describing PRF considered dietary-level driving variables such as DMI, B-vitamin dietary concentration (mg/kg of DM), starch and crude protein (g/kg of DM) and forage NDF (g/kg of DM). Equations developed were required to contain all significant slope parameters and contained no significant collinearity between driving variables. Concordance correlation coefficient was used to evaluate the models on the developmental data set due to data scarcity. Overall, modeling ARS yielded better-performing models compared with modeling PRF, and DMI was included in all prediction equations as a scalar variable. The B-vitamin dietary concentration had a negative effect on the ARS of B1, B2, B3, and B6 but increased the PRF of B2 and B9. The rumen digestible NDF concentration had a negative effect on the ARS of B2, B3, and B6, whereas rumen digestible starch concentration had a negative effect on the ARS of B1 and a positive effect on the ARS of B9. In the best prediction models, the dietary starch increased PRF of B1, B2, and B9 but decreased PRF of B12. The equations developed may be used to better understand the effect of diet and ruminal environment on the true supply of B vitamins to the dairy cow and stimulate the development of better-defined requirements in the future.

Acacia nilotica leaf meal - potential supplement to 25% dorper crosses of local sheep fed a basal diet of natural pasture hay

This research was conducted to evaluate the replacement potential of Acacia nilotica dried leaf meal for Noug Seed Cake (NSC) to supplement low quality grass hay in the diet of crossbred sheep (25% Dorper). In doing so, four treatments were set up in such a way that 0%, 33%, 67%, and 100% NSC is replaced with dried leaf of Acacia nilotica from a conventional supplement while the treatments were kept isonitrogenous. The experiment was set up in a Randomized Complete Block Design, with initials weight used as the blocking factor. Twenty animals were allocated to the four treatments. The experiment consisted of hundred days of feeding trial followed by evaluation of carcass components at the end. In addition, the experimental feed ingredient was studied in vitro for gas production, methane (CH4) production, fractional rate of degradation (Kd), and in vitro dry matter digestibility (IVDMD). In view of chemical composition, grass hay contained lower crude protein (CP = 3.2% DM) and high cell wall contents that makes it lower quality feed. On the other hand, Acacianilotica leaf meal was moderate in quality (CP = 14.3% DM) that can support moderate level of ruminant production. In an in vitro study, Acacia nilotica was found to have lower (P < 0.01) levels of CH4, total gas, kd, and IVDMD compared to the other feed ingredients. This indicates that tannin have an effect on Acacia nilotica feed. Partial and complete replacement of NSC with Acacia nilotica leaf meal significantly increased total dry matter intake (TDMI) (P < 0.001). Average daily gain (ADG) and dressing percentage was also higher for leaf meal supplemented groups. Hot carcass weight was in the range of 14.8–17.8 kg, which is higher than the national average carcass weight for Ethiopian sheep, and it was also found to be higher when NSC was partially (33%) as well as completely replaced by the leaf meal. In general, NSC can be replaced either partially or completely with Acacianilotica leaf meal in the diet of 25% Dorper crosses while weight gain as well as carcass yield is promoted. The maximum inclusion level of Acacia nilotica was 61.3% or 319.2 g per day for 25% Dorper cross sheep fed natural pasture hay as a basal diet.

Nutrient content and in vitro degradation study of some unconventional feed resources of Bangladesh

This study aimed to evaluate six unconventional feed resources of Bangladesh, including water hyacinth (Eichhornia crassipes), banana leaves (Musa paradisiaca), roadside grass (Stenotaphrum secundatum), bamboo leaves (Bambusa vulgaris Scrad), Seaweed (Hypnea sp.) and sugarcane bagasse (Saccharum griffithii). Evaluations were based on dry matter (DM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), ash content, DM and OM digestibilities and fractional rate of degradation. Two conventional feeds, i.e., rice bran and german grass, were used as the positive control. Samples (400 mg) were incubated with rumen liquor in an in vitro fermentation chamber at 0, 6, 12, 24, 48, 72, and 96 h for the degradation kinetic studies. The CP contents of 10.13, 10.63, 10.21, and 8.49 % were found in seaweed, banana leaf, water hyacinth, and bamboo leaf, respectively. The NDF values ranged between 16.5 and 75.6% and ADF varied from 9.7 to 58.8% in this study. The highest value of NDF (75.6%) and ADF (58.8%) were found in sugar cane bagasse and the lowest value of NDF (16.5%) and ADF (9.7%) were as observed in seaweed. However, higher DM degradation (33.5–42.8%) was found in seaweed during the incubation periods of 24–96 h. A significant (P < 0.05) increased of OM degradation (44.9%) compared to other feed resources was also observed in seaweed at 96 h of in vitro incubation. Water hyacinth, banana leaves, german grass, and sugarcane bagasse had greater DM digestibility (32.9–36.3%) compared to roadside grass, bamboo leaves, and rice bran (24.8–29.1%). The higher total OM digestibility of seaweed found (>44.9%) can be associated with the presence of large quantities of fraction b (>39.2 %), resulting in moderate amounts of undegradable fraction (U) (57.2 %). This study provides a comparative estimate of ruminal DM and OM degradation characteristics for seaweed and some other unconventional feed resources, which might be helpful for their inclusion in the diet according to the ruminally undegraded to degraded DM and OM intake ratio.

Porcine in vitro fermentation characteristics of canola co-products in neutral and acidic fermentation medium pH

An in vitro study was conducted to determine effects of reducing pH of porcine in vitro fermentation medium on compositions of glucosinolate degradation products and porcine in vitro fermentation characteristics for solvent-extracted canola meal (SECM) and cold-pressed canola cake (CPCC). Two canola co-products were subjected to porcine in vitro fermentation for 72 h. Accumulated gas production during microbial fermentation was recorded and modeled to estimate kinetics of gas production. Glucosinolate degradation products after microbial fermentation were determined and fermentation medium pH after incubation was recorded. Total and individual volatile fatty acids (VFA) concentrations per unit weight of dry matter (DM) of feedstuffs were determined. On DM basis, SECM and CPCC contained 6.15 and 11.1 µmol/g of glucosinolates, respectively. Goitrin concentration for CPCC was lower (P < 0.05) than that for SECM. Isothiocyanate and indole-3-acetonitrile concentrations for CPCC were lower (P < 0.05) than those for SECM, whereas thiocyanate concentration for CPCC was greater (P < 0.05) than that for SECM. A reduction in fermentation medium pH from 6.2 to 5.2 increased (P < 0.05) goitrin and indole-3-acetonitrile concentrations and decreased (P < 0.05) isothiocyanates concentration for SECM, but did not affect concentration of these 2 glucosinolate degradation products for CPCC. Fermentation medium pH after in vitro fermentation for SECM tended to be greater (P = 0.081) than that for CPCC. Canola co-product type and fermentation medium pH did not interact on gas production parameters. However, a reduction in fermentation medium pH from 6.2 to 5.2 resulted in increased (P < 0.05) lag time and reduced (P < 0.05) fractional rate of degradation and total gas production. Canola co-product type and fermentation medium pH did not interact on total or individual VFA production per gram of DM of feedstuff fermented. However, reducing fermentation medium pH from 6.2 to 5.2 increased (P < 0.05) total VFA and acetate productions, and tended to reduce (P = 0.083) branched-chain VFA production SECM and CPCC. In conclusion, a reduction in fermentation medium pH from 6.2 to 5.2 resulted in increased production of goitrin and indole-3-acetonitriles from SECM-derived glucosinolates, but did not affect production of thiocyanate from SECM-derived glucosinolates. Glucosinolates in CPCC were less affected by the fermentation medium pH used in the current study. It appears that there are other factors other than pH that affect the degradation of canola-derived glucosinolates by microorganisms from hindgut of pigs.

Offering soybean molasses adsorbed to agricultural by-products improved lactation performance through modulating plasma metabolic enzyme pool of lactating cows.

BackgroundAgricultural by‐products, such as corncob powder (CRP), wheat bran (WB), rice husk (RH), defatted bran (DB), and soybean hulls (SH), were widely used as ruminant feed. However, the combination effect of soybean molasses mixed with agricultural by‐products on cow lactating performance remains poorly understood.Methods In vitro fermentation simulation technique was used to select the high ruminal fermentation performance of agricultural by‐products mixed with soybean molasses. The selected mixtures were conducted to further explore the feeding effect on milk performance and blood metabolic enzyme on lactating dairy cows.ResultsIn in vitro simulation, it was confirmed that SH‐SM showed better fermentation performance (including higher maximum gas production, acetate, propionate, and total VFA, but less initial fractional rate of degradation) than other four molasses‐adsorbents, while WB‐SM had the greatest DM and NDF disappearance and NH3‐N and butyrate concentrations among substrates. After the simulation selection, we performed the feed experiment with SH‐SM and WB‐SM compared to the control. For lactating performance, higher (p < .01) milk fat and total milk solid content were observed in WB‐SM, and a tendency improvement of milk protein content (p < .01) was observed in both of the cows fed with WB‐SM and SH‐SM. Among lactating periods, the blood glutamic‐pyruvic transaminase, α‐amylase, and lactate dehydrogenase which associated with amino acid metabolism and carbohydrate metabolism were improved in lactating dairy cows fed with WB‐SM and SH‐SM.ConclusionDietary agricultural by‐products (like wheat bran and soybean hulls) mixed with soybean molasses enhance the lactating performance of dairy cows by improving the host metabolism process of amino acids and carbohydrates. The mixed strategy for agricultural by‐products shows another strong evidence for the resource reuse on dairy industry and reducing the by‐product pollution.

PSIV-9 Effective ruminal degradability of steam-flaked corn is influenced by flake density and starch retrogradation

Abstract The objective of this study was to evaluate in situ ruminal digestion characteristics of steam-flaked corn with large differences in starch availability (SA) using two different models: 1) increasing flake density and 2) exposure to 55°C temperatures to induce starch retrogradation. Five ruminally-cannulated steers (body weight = 390 ± 7.86 kg) were pen-fed a starter diet. In Exp. 1, sifted flakes with flake densities of 257, 296, 335, 373, and 412 g/L (SA: 87%, 76%, 66%, 43%, and 49%, respectively) were evaluated. In Exp. 2, three steam-flaked corn fractions were evaluated: flakes + fines (not sifted), sifted flakes (&amp;gt;4-mm), and sifted fines (&amp;lt; 4-mm). Feed fractions were stored for 3-d at either 23°C or 55°C (average SA across steam-flaked corn fractions: 53.3% and 25.5% respectively). Treatments of Exp. 2 were arranged with a 3 × 2 factorial. Both experiments were duplicated and analyzed as randomized complete block designs. In Exp. 1, the fractional rate of degradation linearly decreased (P &amp;lt; 0.001) and effective ruminal dry matter degradability (ERD) linearly decreased (P &amp;lt; 0.001) from 80.8% to 60.3% as flake density increased from 257 to 412 g/L. In Exp. 2, storage of steam-flaked corn samples at 55ºC for 3-d decreased (P &amp;lt; 0.001) the fractional rate of degradation and ERD by 38.6% and 21.7% across all feed fractions, respectively. Using data from Exp. 1 and 2, SA of sifted flakes was positively correlated (Pearson = 0.8435; R2 = 0.71; P &amp;lt; 0.001) to ERD. The results of the current study demonstrate that decreased SA resulting from starch retrogradation or increased flake density is associated with decreased ERD. Decreases in SA and ERD may indicate that increasing flake density or starch retrogradation could potentially alter the site of digestion in cattle, by increasing postruminal starch flows.

288 Inclusion Effects of Quebracho (Schinopsis Balansaie) Extract and Active Dry Yeast (Saccharomyces Cerevisiae) in Beef Cattle Limit-fed a Grower Ration

Abstract Plant secondary metabolites (PSM) and yeast supplemented in growing cattle have been reported as improving dry matter digestibility (DMD) and reducing enteric methane emissions. This study aimed to evaluate the effect of combined supplementation with condensed tannin (CT; Schinopsis balansae) extract and active dry yeast (ADY; Saccharomyces cerevisiae) on fermentation dynamics, utilizing in vitro gas production (IVGP) technique. A 2 × 2 Latin square design was used to study fermentation patterns of four dietary treatments (CON- no CT and no ADY, ADY alone, CT alone or combined CT + ADY). Animals received daily CT at 1% DM and 10 g of ADY, respectively. On d 0, 7, 14, 21, 28, and 35 rumen inoculum was collected from 23 fistulated steers (284.3 ± 4.1 kg) four hours post-feeding. Samples were incubated under anaerobic conditions at 39oC for 48 h with 200 mg of a grower diet (14.8% CP, 40.6% NDF, 88.5% DM). Gas parameters were analyzed using a mixed linear statistical model. There was a day effect for total gas production (TGP; P &amp;lt; 0.001), non-fiber carbohydrate degradation (P = 0.031) and fractional degradation assuming an asymptote model (P = 0.015). Both asymptote and non-fiber fractional degradation rate estimates had an interaction between Day × TRT (P = 0.001 and 0.0104, respectively). Data were analyzed using polynomial contrasts showed a difference in non-fiber fractional rate of fermentation for CON × CT and CT × ADY (P = 0.052 and 0.054, respectively). This was also true if an asymptote model was assumed (P = 0.0 34 and 0.034, respectively). We concluded that combined supplementation of CT and ADY exhibited similar IVGP trends over time, this may be because animals only received a grower diet at 1.5% shrunk BW. Future studies should investigate the impact of combined supplementation on varying levels of concentrate diets.

Promoting corn stover degradation via sequential processing of steam explosion and cellulase/lactic acid bacteria-assisted ensilage

To improve the utilization efficiency of corn stover , steam explosion pretreatment and cellulase/lactic acid bacteria-assisted ensilage storage were conducted in sequence, mainly focusing on morphological structure, lignocellulose fraction, cellulose accessibility and degradation profile. The results showed that there was a synergistic effect of steam explosion and ensilage storage, where hemicellulose of corn stover was partly degraded during steam explosion processing (70%) or ensilage storage (20–40%). Meanwhile, its morphological structure was apparently broken, increasing cellulose accessibility (2.44, 2.83, 4.08–4.33 mg/g), where enzyme YDL and inoculant QZB were the two most effective additives. Furthermore, rumen effective degradability of corn stover (39.25%, 48.33%, 52.57–54.07%) were increased along with greater rapid degradation fraction (0, 1.67%, 9.16–11.62%) and degradation rate of slow degradation fraction (0.020, 0.034, 0.039–0.048 h−1) . In conclusions, it is suggested that treating corn stover with steam explosion processing and ensilage storage is a feasible way to improve its utilization efficiency.

Chemical composition and porcine in vitro disappearance of heat-pretreated and multi-enzyme-supplemented soybean hulls

Soybean hulls are poorly digested by pigs. Heat-pretreatment or the use of fiber-degrading enzyme supplementation of soybean hulls can potentially improve the digestibility of soybean hulls. Thus, study was conducted to determine the effects of heat pretreating (at 160 °C and 70 psi for 20 min) and supplementing soybean hulls with the multienzyme product, Superzyme-OM (Canadian Bio-Systems, Alberta, Calgary, AB, Canada), which was in liquid form in was dosed at 3 mg/g of sample, which supplied 5100 U of cellulase, 3300 U of pectinase, 720 U of mannanase, 90 U of galactanase, 3600 U of xylanase, 1080 U of glucanase, 4500 U of amylase, and 360 U of protease per kilogram of feedstuff on porcine in vitro nutrient disappearance. The samples were subjected to in vitro enzymatic hydrolysis using pepsin and pancreatin. The samples were incubated in a buffer solution with fresh pig feces as inocula for 72 h to measure gas production. Concentration of volatile fatty acids (VFA) per gram of dry matter (DM) of samples was measured in fermented solutions. On a DM basis, untreated and pretreated soybean hulls contained 10.4 and 10.6 % crude protein. Heat pretreatment reduced total non-starch polysaccharides content of soybean hulls from 71.5 to 64.2%. Heat pretreatment and multi-enzyme supplementation did not interact on coefficient of in vitro disappearance of dry matter (IVDDM). Heat pretreatment increased (P < 0.01) the coefficient of IVDDM of soybean hulls by a mean of 45.5 % whereas multi-enzyme supplementation tended to increase (P = 0.055) the coefficient of IVDDM of soybean hulls by 3%. Heat pretreatment and multi-enzyme interacted (P < 0.05) on fractional rate of degradation and half time such that the fraction rate of degradation for soybean hulls increased (P < 0.01) and the half time for soybean hulls decreased (P < 0.05) when both heat-pretreated and multi-enzyme supplemented. Cumulative gas volume for heat-pretreated soybean hulls at 8, 12, 18, 24, 36, and 48 h after the commencement of incubation was greater (P < 0.01) than that of untreated soybean hulls. Heat pretreatment of soybean hulls increased (P < 0.05) the VFA production per gram of DM of feedstuff. In conclusion, heat-pretreatment and multi-enzyme supplementation increased IVDDM of soybean hulls, implying that the heat pretreatment used in the current study can be used to enhance the nutrient utilization of soybean hulls for pigs.

Effects of dietary energy levels on Pectoralis major mixed muscle protein turnover and body composition in two broiler lines housed in different grow-out environments.

This study determined the Pectoralis (P) major mixed muscle protein turnover (PT) in two meat broiler lines, Line A and Line B, during the finishing grow-out feeding period (21-42days) as affected by the dietary metabolizable energy (ME) levels and ambient temperatures. Experimental finishing diets consisted of 80, 90, 100, 110 and 120% ME of recommended nutrient guidelines for energy level. Fractional synthesis rates (FSR) or fractional degradation rates (FDR) were measured in P.major at day 36 and 42. Protein and fat mass gain were measured, and respective energy retention efficiencies as protein and fat (EREp and EREf) were determined. Metabolic heat production (HP) was also reported. Experimental feeding studies were conducted in cool season (24hr mean: 69.91˚F and 63.98% RH) and in hot season (24hr mean: 77.55˚F and 86.04% RH). Results showed that FSR or FDR values were not affected by dietary ME levels at day 36, whereas reduced FSR (p<.05) were observed at day 42 fed diets with reduced ME levels (≤100% ME) which could have resulted from greater maintenance energy requirement of maturing broilers at that age. Broilers fed reduced ME diets (≤100% ME) maintained protein mass (equivalent to broilers fed ≥100%-120% ME) by reduced FDR and increased feed intake. Grow-out ambient temperature did not affect FSR or FDR values across ME levels. Line B retained higher protein mass, lower fat mass and greater HP compared to Line A. This was followed by higher feed intake in Line B. Further, Line B exhibited higher EREp and lower EREf across dietary ME levels. In summary, PT homeostasis and body composition changes in broiler lines studied seemed to be regulated by the birds' intent to normalize energy intake as per physiological need by controlling feed intake.

Hydratability and improved fermentability in vitro of guar gum by combination of xanthan gum

Dietary fibers with high water-binding capacity (WBC), swelling capacity (SC) and fermentability regulate food intake and intestinal microbiota. However, dietary fibers with such properties are generally rare or expensive. We evaluated SC, WBC, fermentability and bacterial shifts during in vitro fermentations of guar gum (GG), xanthan gum (XG) and the combined gum (CG) of XG and GG. SC and WBC were enhanced by the combination of GG and XG. Fermentation of CG showed similar Short chain fatty acids production and lower molecular weight compared with GG. Analyzing of fermentation kinetics by logistic-exponential model, initial fractional rate of degradation of CG were remarkable higher than GG. Microbiota analysis revealed that GG enriched Fusobacterium, Bacteriodes and Prevotella_9, and CG lead to promotion of Sphaerochaeta, Prevotella_9, Bacteroides and Christensenellaceae_R-7_group. These data suggest that combination of XG to GG changed hydration and fermentation characteristics of GG, and CG resulted in promotion of beneficial microbiota.

In vitro degradation dynamics of neutral detergent fiber and silage quality of waste from production of heart of palm of peach palm

ABSTRACT The objective of the present work was to evaluate the chemical composition, fermentation profile, and degradation parameters of the neutral detergent fiber of three silages made with the waste from production of heart of peach of palm, which consisted of leaf, leaf sheath, and their compound (55% leaf and 45% leaf sheath). The waste was packed in experimental silos and open after sixty days of fermentation; silage samples were collected for determination of chemical composition and degradation parameters of neutral detergent fiber at 0, 3, 6, 9, 12, 24, 36, 48, 72, and 96 h of incubation in vitro. A difference was detected in the dry matter, crude protein, neutral detergent fiber, acid detergent fiber, and lignin contents between the three types of silage. The leaf silage showed a higher fractional degradation rate and a higher potentially digestible fraction of neutral detergent fiber over the 96 h of incubation. As for the fermentative parameters, silage made with the leaf showed a higher pH (3,79) and lactic acid (1,18%), acetic acid (0,39%) and propionic acid (0,24%). The butyric acid was higher for compound silage (0,012%) and ammoniacal nitrogen was higher for sheath silage (0,94%). The leaf silage displayed better chemical characteristics, fermentation parameters and in vitro degradability properties, proving to be the silage with best nutritional value for feeding ruminants.

Application of lactic acid bacteria producing antifungal substance and carboxylesterase on whole crop rice silage with different dry matter.

ObjectiveThis study was conducted to investigate effects of antifungal substance and carboxylesterase-producing inoculant on fermentation indices and rumen degradation kinetics of whole crop rice (WCR) silage ensiled at different dry matter (DM) contents.MethodsDual-purpose inoculants, Lactobacillus brevis 5M2 and Lactobacillus buchneri 6M1, confirmed both activities of antifungal and carboxylesterase in the previous study. The WCR at mature stage was chopped, and then wilted to obtain three different DM contents consisting of 35.4%, 43.6%, and 51.5%. All WCR forages were applied distilled water (CON) or mixed inoculants with 1:1 ratio at 1×105 colony forming unit/g (INO), and ensiled into 20 L mini silo (5 kg) in quadruplicates for 108 d.ResultsThe INO silages had lower lactate (p<0.001) and butyrate (p = 0.022) with higher acetate (p<0.001) and propionate (p<0.001) than those of CON silages. Ammonia-N (p<0.001), lactate (tendency; p = 0.068), acetate (p = 0.030), and butyrate (p<0.001) concentrations of INO silages decreased linearly with increasing DM content of WCR forage. The INO silages presented higher lactic acid bacteria (p<0.001) with lower molds (p< 0.001) than those of CON silages. Yeasts (p = 0.042) and molds (p = 0.046) of WCR silages decreased linearly with increasing DM content of WCR forage. In the rumen, INO silages had higher the total degradable fraction (p<0.001), total volatile fatty acid (tendency; p = 0.097), and acetate (p = 0.007), but lower the fractional degradation rate (p = 0.011) and propionate (p<0.001) than those of CON silage. The total degradable fraction (p<0.001), total volatile fatty acid (p = 0.001), iso-butyrate (p = 0.036), and valerate (p = 0.008) decreased linearly with increasing DM content of WCR forage, while the lag phase (p<0.001) was increased linearly.ConclusionThis study concluded that application of dual-purpose inoculants on WCR silage confirmed antifungal and carboxylesterase activities by inhibiting mold and improving rumen digestibility, while increase of wilting times decreased organic acids production and rumen digestibility.

Effect of replacing soybean meal with marula nut meal on rumen dry matter and crude protein degradability.

In situ rumen degradability of dry matter (DM) and crude protein (CP) in ruminant diets composed of graded inclusion levels of marula nut meal (MNM) as a protein source to replace soybean meal were evaluated. The five diets denoted as diet 1 (0.0gkg-1 MNM: control), diet 2 (45.5gkg-1 MNM), diet 3 (91.7gkg-1 MNM), diet 4 (138.4gkg-1 MNM), and diet 5 (185.9gkg-1 MNM) were tested. Three cannulated mid-lactating Holstein cows were used to incubate triplicate subsamples of each diet for 2, 4, 8, 16, 24, and 48h in polyester bags. The soluble fractions of DM and CP increased (P < 0.05) with increasing levels of MNM (138.4-185.9gkg-1 MNM). However, the insoluble but degradable fractions of DM and CP increased (P < 0.05) with decreasing levels of MNM (45.5-0.0gkg-1 and 91.7-0.0gkg-1 MNM, respectively). While the degradation rate of fraction and the effective degradability of DM increased (P < 0.05) with decreasing levels of MNM (91.7-0.0gkg-1), those of CP increased with increasing levels of MNM (138.4-185.9gkg-1 MNM) in the diet. These results suggest that dietary inclusion of MNM up to 91.7gkg-1 in ruminant diets can provide undegradable protein to be absorbed in the small intestines and used for metabolic function, while an inclusion of up to 185.9gkg-1 can be degraded in the rumen for microbial protein synthesis.

Effects of Potato By-products Containing Glycoalkaloid on Rumen Fermentation Characteristics

The present study was conducted to investigate the effects of feed types (powder vs. pellet) from potato by-product containing glycoalkaloid on rumen fermentation with different rumen pH (low vs. high) using in vitro technique. Rumen fluid was collected from two cannulated Hanwoo heifers before morning feeding (high rumen pH at 6.71) and 3 h after feeding (low rumen pH at 6.20). A 0.5 gram of powder or pellet from potato by-product was incubated in the rumen buffer for 48 h at 39℃. Four replications for each treatment were used along with two blanks. Pellet had higher (p<0.05) the immediately degradable fraction, the fractional degradation rate, and the lag phase than those of powder. However, feed type had no effects on the potentially degradable fraction and the total degradable fraction. In fermentation characteristics, powder had higher (p<0.05) concentrations of ammonia-N, total volatile fatty acid (VFA), and acetate than those of pellet. In addition, a high rumen pH had higher (p<0.05) concentrations of ammonia-N and acetate, but lower (p<0.05) total VFA concentration than those of a low rumen pH. The interaction effects between feed type and rumen pH were found on the total degradable fraction and concentrations of ammonia-N, total VFA, and acetate. The present study concluded that generally feed type had no effects on rumen degradation kinetics, but potato by-product in the powder form is recommended due to produce higher fermentation characteristics than in the pellet form.