Youden Square Research Articles

Fungal Phytase Increased Ileal and Total Tract Digestibility of Phosphorus of Cold-Pressed Canola Cake and Canola Meal Diets in Growing Pigs

The co-product canola meal contains little fat and has been used in swine production as a protein source for several decades. More recently, locally produced canola cake has also become available that contains important quantities of residual oil. Both canola co-products contain a considerable quantity of phosphorus (P) with low availability. Phytase supplementation can increase P digestibility in canola meal but its efficacy remains unclear for canola cake containing high residual oil. To explore whether phytase supplementation can increase digestibility of P and other nutrients in canola cake, four diets containing 500 g of locally produced cold-pressed canola cake or canola meal, with or without supplemental phytase (Ronozyme HiPhos; Aspergillus oryzae origin)/kg, were fed to seven pigs (initial body weight; 55.9 ± 3.8 kg) in four 9-day periods following a 4 × 4 Latin square plus a 4 × 3 Youden square. Phytase supplementation increased phytase activity from below the detection limit to reach a minimum of 1000 phytase units/kg in the canola meal and cake diets; respectively. Phytase supplementation increased (p < 0.05) coefficients of ileal and total tract digestibility of P by 60% and 46% for canola meal and 76% and 57% for canola cake, respectively, but did not affect the digestibility of crude protein or gross energy. Ileal or total tract digestibility of P did not differ between the canola cake and canola meal diets in growing-finishing pigs. In conclusion, fungal phytase is effective in increasing the P digestibility of canola cake similar to in canola meal fed to growing-finishing pigs. The similar ileal or total tract digestibility of P in canola meal and cake diets either with or without phytase supplementation indicated that the residual oil in canola cake did not affect P digestion and did not affect the efficacy of phytase in increasing P digestibility.

Nutritional values of soybean meal from different sources in multiparous sows

This study determined the available energy content, apparent total tract digestibility (ATTD) of nutrients, and ileal amino acid (AA) digestibility of soybean meal (SBM) from different sources in non-gestating, non-lactating sows. In Exp. 1, 24 multiparous Landrace × Yorkshire (LY) sows (parity 3–5) were allotted to a replicated 12 × 3 Youden square design consisting of 12 diets and 3 periods. The 12 diets included 11 test diets containing SBM from different sources and a corn-based diet. Each period included a 5-d adaptation and a 5-d total fecal and urine collection. In Exp. 2, 8 multiparous LY sows (parity 3–5) were allotted to a replicated 4 × 3 Youden square design with 4 diets and 3 periods. The 4 diets included a nitrogen-free diet and 3 SBM diets (3 representative SBM samples were selected from Exp. 1). Our results showed that the coefficient of variation of ether extract, crude fiber, neutral detergent fiber, and acid detergent fiber levels in 11 SBM samples were > 20%. There were no differences in digestible energy (DE), metabolizable energy (ME), and the ATTD of gross energy, nitrogen, and neutral detergent fiber values between different SBM samples (P > 0.05). Additionally, no differences in AA digestibility were identified among the 3 representative SBM samples (P > 0.05). In conclusion, there were no differences in DE, ME, and AA digestibility between different SBM samples fed to multiparous non-gestating sows. When formulating diets for sows, it is important to consider the differences in the nutritional value of SBM at different physiological stages.

APPLICATION OF YATES METHOD FOR MISSING DATA ESTIMATION IN YOUDEN SQUARE DESIGN AND ANALYSIS

The Youden square design is widely used in experimental research to control two sources of variability, but missing data can compromise the results. Addressing missing data is critical to maintaining the integrity and reliability of such experiments. This paper proposes to adapt the Yates method to handle missing data specifically in Youden square designs. We begin by outlining the structure of the Youden square design and the challenges posed by missing data. The Yates method, known for its robustness in estimating missing data, is adapted to fit this design. We demonstrate its effectiveness through simulations and real-world case studies. The simulation involved generating experimental data with one missing value, and the case study analyzed chemical process research with critical missing data points. The results show that the Yates method maintains statistical validity and improves data completeness compared to traditional methods. Its advantage lies in utilizing Youden's quadratic structure for more accurate estimation. This study highlights the Yates method as a solution to handle missing data, improving the quality and reliability of experimental research.

Potential New Methods to Analyze Basal and Total Endogenous Protein Losses of Host and Bacterial Origin in Pigs

BackgroundCurrent systems for assessing protein quality such as the Digestible Indispensable Amino Acid Score correct apparent amino acid (AA) digestibility for basal endogenous protein losses (bEPL), ignoring the potential influence of the diet on these losses. However, the quantification of total endogenous protein losses (tEPL) poses a challenge. ObjectivesTo evaluate different methods for quantifying tEPL and bEPL, and to assess their potential in discriminating between tEPL originating from bacteria and host. MethodsUsing an incomplete Youden square design, 12 ileal cannulated pigs received 10 different protein sources, and a nitrogen-free (NF) diet. Ileal digesta were collected on days 6 and 7 of each 1-wk feeding period, to quantify endogenous protein losses (EPL) and analyze apparent ileal digestibility. Ileal EPL were estimated based on 1) 16S-+18S gene copy quantitative polymerase chain reaction, 2) diaminopimelic acid (DAPA)+18S, 3) differential AA profiles in digesta, EPL, and bacteria, equaling tEPL, and 4) an NF diet and 5) whey protein isolate (WPI), equaling bEPL. ResultsIleal bEPL based on the NF and WPI method correlated moderately to highly (r = 0.69, P < 0.05), but the NF method probably underestimated bEPL. In pigs fed the WPI diet, EPL based on the WPI and AA profile method were highly correlated (r = 0.88, P < 0.01). Overall, tEPL based on the AA profile method were moderately correlated with the 16S+18S method (r = 0.58, P < 0.001), and DAPA+18S (r = 0.57, P < 0.001). Low correlations were observed between bacterial tEPL based on the AA profile method and 16S or DAPA. Host tEPL based on the AA profile method and 18S were weakly correlated (r = 0.39, P < 0.001). ConclusionsThe AA profile method seems the most appropriate method for tEPL quantification, whereas the WPI method is preferred for bEPL quantification. Despite challenges in distinguishing between bacterial and host EPL, it is evident that bacterial proteins substantially (on average 37%–83%, depending on method) contribute to the EPL.

Feeding a Multi-Enzyme Blend to Enhance the Nutrient Digestibility of Wheat-Canola Expeller Diets in Ileal-Cannulated Weaned Pigs.

Canola expeller (CE) contains ~200 g/kg residual oil, but also fiber that impairs nutrient digestibility in weaned pigs. To study if feed enzymes increase digestibility, six diets containing either the basal or two CE samples mixed in at 250 g/kg (CE-A or CE-B) were formulated with or without a multi-enzyme blend containing cellulase, xylanase, glucanase, amylase, protease, invertase, and pectinase. The basal diet containing 620 g/kg wheat and 150 g/kg barley served as control. Twelve ileal-cannulated barrows (9-15 kg) were fed the six diets in a replicated 6 (pigs) × 3 (periods) Youden square. Ileal digestibility of gross energy and amino acids was 5% greater for basal than CE diets without differences between CE samples. Diet energy values were 4% greater for CE than basal diets due to residual oil in CE. Inclusion of the multi-enzyme blend increased total tract digestibility of energy of the basal but not CE diets by 2%. Net energy value was greater for CE-A than CE-B because CE-A contained more residual oil. In conclusion, feeding 250 g/kg CE increased diet energy values; thus, CE can substitute added fat in weaned pig diets. Feeding the multi-enzyme blend increased the energy digestibility of wheat and barley-based diets fed to weaned pigs. However, research is needed to identify enzyme combinations that increase the nutrient digestibility of CE.

Interactive Effects of Dietary Fiber and Lipid Types Modulate the Predicted Production and Absorption of Cecal and Colorectal Short-Chain Fatty Acids in Growing Pigs

BackgroundHigh-fiber diets are supplemented with lipids to meet the required energy content, but data on the interactions between dietary fiber (DF) and lipid types on gastrointestinal fermentation in pigs are scant. ObjectivesThis study aimed to use a combination of in vivo and in vitro fermentation methodologies to determine the interactive effects of DF and lipid types on short-chain fatty acid (SCFA) production and absorption and organic matter (OM) fermentability in the cecum and colorectal tract of pigs. MethodsEight ileal- and cecal-cannulated Yorkshire barrows were fed either pectin- or cellulose-containing diets that were supplemented with either corn oil or beef tallow in 2 independent Youden squares with a 2 × 2 factorial arrangement of treatments (n = 6). Ileal and cecal digesta were collected, freeze-dried, and fermented using inoculum from fresh cecal digesta and feces, respectively, to determine individual SCFA production and absorption and fermentability of OM. ResultsInteractions (P < 0.001) between DF and lipid types were observed in which the addition of beef tallow decreased the quantity of cecal and colorectal acetic acid production and cecal acetic absorption, cecal butyric production, predicted cecal OM fermentability, and predicted colorectal propionic acid in pectin diets, but the effects were not observed for cellulose diets. The addition of beef tallow increased (P < 0.001) the production of cecal butyric and propionic acids during in vitro fermentation in cellulose diets and apparent total tract digestibility (ATTD) of OM in pectin diets. ConclusionsThe interactions between DF and lipids on gastrointestinal fermentation largely depend on the degree of saturation of fatty acids in dietary lipids. The addition of beef tallow selectively decreased the production and absorption of individual SCFAs in pectin and cellulose diets but increased cecal butyric and propionic acid production in cellulose diets and the ATTD of OM in pectin diets.

157 Effects of increasing dietary protein concentration on digestibility of amino acids by growing pigs

Abstract Two experiments were conducted to test the hypothesis that the standardized ileal digestibility (SID) of amino acids (AA) by growing pigs is not influenced by dietary protein concentration if all AA are supplied by soybean protein isolate (SPI) or casein. In Exp. 1, cannulated pigs [n = 12; average body weight (BW) = 39.22 kg; SD = 3.96] were allotted to a replicated 6 × 3 Youden square design with the 6 diets and 3 periods. Five diets were formulated to contain 7 to 35% SPI. An N-free diet was also used. In Exp. 2, cannulated pigs (n = 24 average BW = 23.12 kg; SD = 2.89) were allotted a quadruplicated 6 × 2 Youden square design with the 6 diets and 2 periods. Five diets were formulated to contain 6.75 to 33.75% casein. An N-free diet was also used. Ileal digesta were collected and analyzed for dry matter (DM), Cr, and AA. The statistical models included diet as a fixed variable and square, animal, and period as random effects. Polynomial contrasts were used to test linear and quadratic effects of increasing dietary protein. Results from Exp. 1 indicated that the apparent ileal digestibility (AID) of DM linearly (P = 0.001) decreased and the AID of all AA quadratically (P &amp;lt; 0.05) increased as the inclusion of SPI increased in the diets (Table 1). The SID of His and Trp was not affected by the inclusion of SPI in the diets. However, the SID of Arg, Leu, Lys, Phe, Thr, and Val linearly (P &amp;lt; 0.05) decreased, and the SID of Ile and Met tended to linearly (P &amp;lt; 0.10) decrease as the inclusion of SPI in the diets increased. Results from Exp. 2 indicated that the AID of DM tended to linearly decrease (P = 0.089) as the inclusion of casein increased in the diets (Table 2). The AID of most AA increased quadratically (P &amp;lt; 0.01) and the AID of Trp tended to increase (quadratic, P = 0.068) with increasing inclusion rate of casein. The SID of most AA was independent of casein levels. In conclusion, the anti-nutritional factors may have been increased in the diets as the inclusion of SPI increased and thus resulted in reduced SID values. However, the SID values were not influenced by increasing dietary protein if all AA were supplied by casein that does not contain anti-nutritional factors. Therefore, it is concluded that pigs have the capacity to absorb peptides and AA with the same efficiency if the protein concentration is 30% as if it is 6%. Dietary protein concentration itself, therefore, is not likely to limit AA absorption. However, even small amounts of anti-nutritional factors appear to negatively impact the SID of AA.

Determination and prediction of the net energy content of wheat bran for pregnant sow

ABSTRACT Two experiments were conducted to determine net energy (NE) values of wheat bran ingredients and develop a prediction equation for NE of wheat bran. In each experiment, 12 multiparous pregnant sows were allocated to two 3 × 6 Youden squares with three consecutive periods and six diets in each square. The study consisted of six diets, including a corn-soybean meal basal diet and five diets formulated with 29.2% wheat bran. Each period lasted for 10 d, with 5 d allocated for adaptation and followed by 5 d for heat production measurement. Sows were provided feed at 604 kJ/kg BW0.75·d−1. On day 10, sows underwent fasting to measure fasting heat production. Results indicated that the inclusion of wheat bran in the diets significantly reduced digestibility of energy and nutrients in (p < 0.05). The average net energy (NE) content of wheat bran was determined to be 8.8 MJ/kg DM. A regress equation NE = 7.968 + 0.28 × CP + 0.607 × EE − 0.782 × ash − 0.05 × hemicellulose (R2 = 0.98, p < 0.01) was found to accurately predit the NE value when feeding pregnant sows with wheat bran-based diets. In conclusion, the net energy content of wheat bran fed to pregnant sows ranged from 7.24 to 10.67 MJ/kg DM and can be effectively estimated using proximate analysis methods.

Standardized ileal digestibility of amino acids in Chinese fermented soybean meal from different sources fed to mid and late-gestating sows.

We determined apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of crude protein (CP) and amino acids (AA) in fermented soybean meal from five different sources (FSBM 1 to 5) in China when fed to mid and late-gestating sows. Twenty-four parity four sows (12 at 30 d in gestation and 12 at 80 d in gestation) were fitted with a T-cannula in the distal ileum and used in this experiment. Sows were randomly assigned to a replicated 6 × 3 Youden square design including six diets and three periods. Six diets were provided for sows in mid and late gestation, including a nitrogen-free diet and five test diets containing 26% FSBM from different sources. Results showed that there were differences in AID and SID of CP among the different FSBM samples, but no differences between sow physiological stages were observed. Specifically, when mid-gestating sows were fed FSBM 2, the AID of CP was the lowest, whereas FSBM 3 exhibited a greater AID of CP when compared to the other FSBM samples (P < 0.01). Furthermore, during late gestation, FSBM 3 consistently had greater SID of CP when compared to other FSBM samples (P < 0.01). The ileal digestibility of most AA varied with different FSBM samples. In both mid and late gestation, differences (P < 0.05) were observed for AID of lysine, tryptophan, histidine, and arginine across different FSBM samples. Similarly, the AID of dispensable AA (cysteine, glutamine, and serine) also exhibited differences (P < 0.05) across different FSBM samples in both mid and late-gestating sows. For mid-gestating sows, SID differences relating to lysine, phenylalanine, tryptophan, threonine, and arginine were observed among different diets (P < 0.05). In late-gestating sows, SID values for lysine, tryptophan, leucine, and arginine differed across diets (P < 0.05). Furthermore, the ileal digestibility of some dispensable AA was influenced by physiological stage, as evidenced by greater AID and SID values for glycine, glutamine, cysteine, and serine in late-gestating sows when compared to mid-gestating sows (P < 0.01). In summary, our study determined AA ileal digestibility of different FSBM fed to mid and late-gestating sows. We observed that the AA ileal digestibility differed among five FSBM samples, but the physiological stage of sows did not affect the ileal digestibility of CP and most AA. Additionally, when formulating diets for sows, it is crucial to consider the nutritional value differences of FSBM.

Evaluation of the effects of hempseed cake on plasma metabolites and cytokines in response to an LPS challenge in finishing steers

A lipopolysaccharide (LPS; 0.25 µg LPS/kg of body weight (BW)) challenge in steers ( n = 5; initial BW = 542 kg, SD = 40 kg; Youden square) was conducted to evaluate feeding 0% (dry matter basis; control) or 20% hempseed cake (HEMP) or corn distillers grains (DDGS) on plasma metabolites and cytokines. Plasma isoleucine, leucine, tryptophan, aspartic acid, glycine, tyrosine, total nonessential amino acids, interleukin-1α (IL-1α), interleukin-36 receptor antagonist (IL-36RA), and tumor necrosis factor-α (TNF-α) decreased ( P ≤ 0.04) in steers fed hempseed cake compared to steers fed DDGS after the LPS challenge. These data suggest that hempseed cake may influence inflammation by altering cytokine production and by increasing degradation and/or utilization of some amino acids.

Determining the nutritional values of new corn varieties on pigs and broilers.

The objective of this study was to evaluate the nutritional values of three new corn varieties (high-iron corn, cadmium-resistant corn, low-phytate phosphorus corn) cultivated with molecular marker-assisted selection breeding technique fed to growing pigs and broilers. Exp. 1 was conducted to compare the nutritional values of high-iron corn, high-chromium corn, low-phytate phosphorus corn and conventional corn fed to growing pigs based on a 15 × 2 Youden square design. Exp.2 was conducted to compare the nutritional values of high-iron corn, low-phytate phosphorus corn and conventional corn fed to broilers based on a completely randomized design. Parameters including nutrient digestibility, available energy and amino acids, and mineral deposition were measured. The results shows that the iron content in the high-iron corn and the cadmium content in the cadmium-resistant corn were 29.608 mg/kg and 0.0057 mg/kg, respectively, both were greater than those in the other three kinds of corns. When fed to growing pigs, the neutral detergent fiber digestibility of the high-iron corn group was lower than that of the conventional corn group (p < 0.05), and the acid detergent fiber digestibility of the high-iron group and the low-phytate phosphorus corn group was lower than that of the conventional corn group (p < 0.01). In addition, the digestible energy value of the high-iron corn in growing pigs was lower than that of the conventional corn (p < 0.05). When fed to broilers, it was observed that the tibia length of the low-phytate phosphorus corn group and the high-iron corn group was lower than that of the conventional corn group (p < 0.05). Moreover, the iron emission in feces of broilers fed the low-phytate phosphorus corn was lower than those fed the conventional corn and the high-iron corn (p < 0.05). In conclusion, modern breeding techniques could provide new plant ingredients which have potential benefits to pig and broiler production, but the comprehensive effects may be better when applied to growing pigs considering growth performance and environment effects. The breeding techniques related to the current study rarely changed the available energy values of the corn in growing pigs and broilers.

The digestible indispensable amino acid score (DIAAS) in eggs and egg-containing breakfast meals is greater than in toast breads or hash browns served without eggs

Abstract The objectives of this experiment were to determine the digestible indispensable amino acid score (DIAAS) for eggs cooked in different forms and in traditional egg-bread or egg-hash brown combinations, and to test the hypothesis that DIAAS in eggs is greater than in breads or potatoes. Nine ileal cannulated gilts (average initial body weight: 51.1 ± 6.0 kg) were allotted to a 9 × 6 Youden square design with nine diets and six 7-day periods. Fried egg, boiled egg, scrambled egg, English muffin, Texas toast, and hash brown were included in the experiment. Six diets each contained one source of protein and three diets were combinations of fried eggs and English muffin, boiled eggs and Texas toast, or scrambled egg and hash brown. A nitrogen-free diet was also used and fed to all pigs in one period. The standardised ileal digestibility (SID) of crude protein (CP) and amino acids (AA) was calculated, and DIAAS was calculated for the individual ingredient and combined meals for children between 6 and 36 months and individuals older than 3 years. For both age groups, all cooked eggs had greater (P &lt; 0.001) DIAAS compared with the other foods, and hash brown had greater (P &lt; 0.001) DIAAS than both breads. All combined meals had DIAAS greater than 75 and there were no differences between measured and predicted DIAAS for the combined meals. In conclusion, eggs have ‘excellent’ protein quality for individuals older than 6 months and can compensate for the lower protein quality in plant-based foods, and DIAAS obtained from individual ingredients are additive in mixed meals.

300 Metabolizable Energy and Amino Acid Digestibility by Growing Pigs may be Reduced if Excessive Heat is Applied During Drying of Corn

Abstract Two experiments were conducted to test the hypothesis that both drying temperature and drying time affect the standardized ileal digestibility (SID) of amino acids (AA) and metabolizable energy (ME) in corn fed to growing pigs. A single source of corn was divided into 11 batches that were dried using a “drying chamber” at 80ºC for 1.5, 3.0, 24, or 48 h or at 130ºC for 1.5, 3.0, 6.0, 9.0, 12, 24, or 48 h. Exp. 1 was designed to determine the concentrations of ME in the 11 batches of corn. Eleven diets based on each batch of corn were formulated. Growing barrows (n = 88; BW = 20.6 ± 1.2 kg) were allotted to the 11 diets in a randomized complete block design with 8 blocks of 11 pigs. Urine and fecal samples were collected for 4-days after 7-days of adaptation. Contrast statements were used to determine effects of temperature and drying time within temperature. Exp. 2 was designed to determine the SID of AA in the 11 batches of corn. An N-free diet and 11 diets that each contained one of the 11 batches of corn as the sole source of AA were formulated. All diets contained 0.40% chromic oxide as an indigestible marker. Twenty-four growing pigs (22.8 ± 5.1 kg) that had a T-cannula installed in the distal ileum were allotted to a replicated 12 × 4 Youden square with 12 diets and four 7-day periods in each square. Therefore, there were 8 replicate pigs per diet. Ileal digesta were collected on days 6 and 7 of each 7-days period. Data were analyzed as described for Exp. 1. Results indicated that ME (dry matter basis) was greater (P &amp;lt; 0.01) if corn was dried at 130ºC than at 80ºC (Table 1). The ME (dry-matter basis) increased (quadratic, P &amp;lt; 0.04) with drying time at 80ºC, whereas it decreased at 130°C (quadratic, P &amp;lt; 0.05). The SID of AA did not differ between corn dried at 80°C and 130°C, except that the SID of Lys was less (P &amp;lt; 0.05) if corn was dried at 130°C than at 80°C. The SID of most AA decreased (linear or quadratic, P &amp;lt; 0.05) as time of drying increased at 130°C. In conclusion, the SID of AA and ME in corn are not reduced by extending the time of drying at 80°C. However, the digestibility of AA is reduced if corn is dried at 130°C and the longer the time of drying the more the SID of AA is reduced. Values for ME in corn are increased if corn is dried at 130°C rather than 80°C.

Predicting energetic values of cereal grains and byproducts using a computer-controlled simulated digestion system for growing pigs

The objective of this study was to predict the apparent total tract digestibility (ATTD) of gross energy (GE), digestible energy (DE), and metabolizable energy (ME) of cereals and byproducts using an in vitro digestion procedure automatically progressed in a computer-controlled simulated digestion system (CCSDS) for growing pigs. In in vivo test to determine the ATTD of GE, DE and ME of feed ingredients, 15 barrows (30.2 ± 2.4 kg of initial body weight) were allotted to a 15 × 6 Youden square design with 15 experimental diets in 6 periods to give 6 replicates per diet. Diets included a corn-soybean meal-based basal diet and 14 test diets formulated with 14 samples of cereals and byproducts. The in vitro digestible energy (IVDE) and IVDE/GE were determined using CCSDS with 5 replicates for each sample. Principal components analysis showed that similar positions of samples were observed on a two-dimensional plot of PC1 and PC2 extracted from chemical composition and each of DE, ME, or IVDE. The ratios of IVDE to DE or ME among 14 samples ranged from 87.7–110.4 % and 91.1–112.9 %, but ranged from 97.8–103.5 % or 100.2–105.7 % when both paddy rice and wheat shorts were excluded in consideration of lever effect. Models to predict DE and ME from IVDE were DE = 0.7428 × IVDE + 945 (R² = 0.71, root mean square error (RMSE) = 157 kcal/kg DM, P < 0.01), ME = 0.7465 × IVDE + 839 (R² = 0.76, RMSE=139 kcal/kg DM, P < 0.01) when 14 samples were included, but regression equations were DE = 0.6924 × IVDE + 1173 (R² = 0.91, RMSE = 49 kcal/kg DM, P < 0.01) and ME = 0.6876 × IVDE + 1098 (R² = 0.95, RMSE = 34 kcal/kg DM, P < 0.01) when paddy rice and wheat shorts were excluded. Our results indicate that IVDE determined with a novel CCSDS can precisely predict the DE and ME of cereals and byproducts with lower fiber content (ADF < 6.01 % DM) for growing pigs.

Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows

BackgroundTwo studies were designed to determine standard ileal crude protein (CP) and amino acid (AA) digestibility of soybean meal (SBM) from different origins fed to non-pregnant and pregnant sows. Seven solvent-extracted SBMs from soybeans produced in the USA, Brazil, and China were selected. In Exp. 1, eight different diets were created: a nitrogen (N)-free diet and 7 experimental diets containing SBM from different origins as the only N source. Eight non-pregnant, multiparous sows were arranged in an 8 × 8 Latin square design (8 periods and 8 diets). In Exp. 2, the diet formula was the same as in Exp. 1. Eight gestating sows (parity 3) were assigned to 4 different diets in a replicated 4 × 3 Youden square design (three periods and four diets) in mid-gestation and again in late-gestation stages.ResultsWhen fed to non-pregnant and late-gestating sows, the standardized ileal digestibility (SID) of CP and most AAs from different SBM were not significantly different (P > 0.05). When fed to mid-gestating sows, the SID values for Arg, His, Lys, Phe, Cys, Gly, Ser, and Tyr in SBM 1 were lower than in SBM 4 and 5 (P < 0.05), whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4 (P < 0.05). SID values for Ile, Ala, and Asp from SBM 4 were lower than in SBM 1 and 5 (P < 0.05). Sows had significantly greater SID values for Lys, Ala, and Asp during mid-gestation when compared with late-gestation stages (P < 0.05). Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows (P < 0.01), whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows (P < 0.01).ConclusionsWhen fed to mid-gestating sows, the SID values for most AAs varied among SBM samples. The SID values for Lys, Met, Val, Ala, Asp, and Tyr in SBM were affected by sow gestation stages. Our findings provide a cornerstone for accurate SBM use in sow diets.

Digestibility and nitrogen balance of goats on high and low protein rations supplemented with a commercial tannin feed-additive

ABSTRACTDespite the increasing importance of goat production in response to high demand for their products and their relative robustness to environmental stressors, and in contrast to other ruminant species, little data is available on how tannin extract feeding affects their feed intake, nutrient digestion and nitrogen (N) metabolism. Therefore, a trial in Oman investigated the respective variables by using a commercial tannin feed additive. In a 4 (treatments) x 3 (periods) x 2 (animals) Youden square, two weaned Batinah bucks each were fed a high or low protein diet of Rhodes grass hay and crushed barley grain, with or without the addition of a chestnut and quebracho tannin extract at 2 g/kg metabolic weight. Feed offered, feed refused and faeces and urine excreted were quantified to determine diet digestibility, total N excretion, N retention and rumen microbial protein synthesis (MPS). Due to their young age and low live weight, feed intake of goats was relatively low. Crude protein level and tannin addition had no statistically significant effect on dry matter (DM) and N intake, DM digestibility, N excretion in faeces and urine, as well as MPS. In consequence, no benefit of tannin feeding could be confirmed for the goats’ N retention, irrespective of diet composition. These results indicate, on one hand, an effective neutralisation of the tested tannin extract along the gastrointestinal tract of goats, but on the other hand, that stimulation of MPS or N retention by tannins cannot be evidenced when diet components are present that simultaneously release energy and protein, as is the case with barley.

Type and Amount of Dietary Fiber Influence the Hindgut Synthesis of Organic Acids from Fermentable Material of Both Total and Nondietary Origin in a Pig Model of the Adult Human

BackgroundOrganic acid synthesis by the hindgut microbiota is commonly believed to be mainly of fermentable material of dietary origin. ObjectiveThis study aimed to determine the hindgut organic acid synthesis from fermentable material of dietary (mainly fiber) or nondietary origin for different types and amounts of dietary fiber in growing pigs used as a model for adult humans. MethodSeven fiber-containing diets were formulated: 4 fiber types (cellulose, gum acacia, oligofructose, and pectin) at 6% of the diet and 3 (gum acacia, oligofructose, and pectin) at 3% as the sole fiber source. Ileal cannulated female pigs (n = 14; Landrace/Large white) were fed the fiber-containing diets (n = 6 pigs/diet) for 11 days (fiber phase) followed by 3 days on a fiber-free diet (fiber-free phase), using a replicated Youden square. Ileal digesta for each phase were collected and fermented in vitro with a pooled fecal microbial inoculum prepared from feces collected during the fiber phase to determine the organic acids synthesized from fermentable material of dietary (fiber phase) and nondietary (fiber-free phase) origins. ResultsThe total amount of each individual organic acid synthesized during in vitro hindgut fermentation differed (P ≤ 0.05) across the types and amounts of dietary fiber intake. For example, the amount of acetate was 3.6-fold higher (P ≤ 0.05) for pigs fed the 6% pectin-containing diet than those fed the 6% oligofructose-containing diet. The nondietary substrate contributed between 36% (hexanoate) and 70% (succinate) to the total hindgut organic acid synthesis. The adaptation to the different fiber-containing diets led to different amounts of some organic acids of nondietary origin. ConclusionsThe total amount of organic acids synthesized in the hindgut by the resident microbes is influenced by the type and amount of dietary fiber consumed. This study quantifies the interaction between both dietary and nondietary fermentable materials in hindgut fermentation.

The ileal and total tract digestibility fibre and nutrients in pigs fed high-fibre cereal-based diets provided without and with a carbohydrase complex.

The effect of carbohydrase can be variable according to the complexity of cereal grains and co-products. Studies on the effect of carbohydrase on cereal diets varying in complexity are scarce. This study was conducted to investigate the apparent ileal (AID) and total tract digestibility (ATTD) of energy, fibre and nutrients in pigs fed diets based on cereal grains and co-products without and with supplementation with a carbohydrase complex in the form of xylanase, arabinofuranosidase and β-glucanase. The experiment was carried out as an 8×4 Youden Square design (eight diets and four periods by two blocks) using 16 growing pigs (33.3±0.8kg) surgically fitted with a T-cannula in the terminal ileum. The pigs were fed eight experimental diets based on either - maize, wheat, rye, or a wheat and rye mix that were provided with or without enzyme supplementation. The AID and ATTD of DM, organic matter, energy, CP, fat, starch, and soluble and insoluble non-starch polysaccharides (NSPs) were studied using titanium dioxide as an indigestible marker. There was a cereal type effect (P<0.05) of the AID of most of the nutrients investigated but ash and NSP and some of its constituents but with no interactions between cereal types and carbohydrase supplementation (P>0.05). The ATTD of nutrients in the large intestine was mainly influenced by the fibre composition and was significantly lower (P<0.001) for NSP, protein and energy for the Maize than the other diets. Supplementation of the cereal diets with the carbohydrase complex partially degrades arabinoxylan (AX) and β-glucan giving rise to a generally higher AID of high-molecular weight arabinoxylan (P=0.044), starch (P=0.042), a tendency (P<0.10) of higher AID of non-cellulosic polysaccharide glucose residue (β-glucan) and soluble arabinoxylan (AX) whereas none of the other components were affected (P>0.05). Collectively, the results indicate that the carbohydrase complex degrades AX in the stomach and small intestine, leading to a higher AID but with no influence on the ATTD of fibres, nutrients, and energy.

Wheat bran inclusion level impacts its net energy by shaping gut microbiota and regulating heat production in gestating sows

An accurate estimation of net energy (NE) of wheat bran is essential for precision feeding of sows. However, the effects of inclusion level on NE of wheat bran have not been reported. Inclusion level was hypothesized to impact NE of wheat bran by regulating gut microbiota and partitioning of heat production. Therefore, twelve multiparous sows (Yorkshire × Landrace; 2 to 4 parity) were assigned to a replicated 3 × 6 Youden square with 3 successive periods and 6 diets in each square. The experiment included a corn-soybean meal diet (WB0) and five diets including 9.8% (WB10), 19.5% (WB20), 29.2% (WB30), 39.0% (WB40) and 48.7% wheat bran (WB50), respectively. Each period included 6 d of adaptation to diets followed by 6 d for heat production measurement using open-circuit respiration chambers. Compared with other groups, WB30, WB40, and WB50 enriched different fiber-degrading bacteria genera (P < 0.05). Apparent total tract digestibility of neutral detergent fiber and acid detergent fiber of wheat bran were greater in WB30 and WB40 (P < 0.05). Physical activity (standing and sitting) decreased as inclusion level increased (P = 0.04), which tended to decrease related heat production (P = 0.07). Thermic effect of feeding (TEF) was higher in WB50 than other treatments (P < 0.01). Metabolizable energy of wheat bran was similar among treatment groups (except for WB10). NE of wheat bran conformed to a quadratic regression equation with inclusion level (R2 = 0.99, P < 0.01) and peaked at an inclusion level of 35.3%. In conclusion, increasing inclusion level decreased energy expenditure of sows on physical activity and promoted growth of fiber-degrading bacteria, which improved energy utilization of fiber. Fermentation of wheat bran fiber by Prevotellaceae_UCG-003 and norank_f__Paludibacteraceae might increase TEF. Consequently, sows utilized energy in wheat bran most efficiently at an inclusion level of 35.3%.

Nutritional values of cottonseed meal from different sources fed to gestating and non-pregnant sows.

This study set out to determine the apparent total tract digestibility (ATTD) of the nutrients and energy in six cottonseed meal (CSM) feedstuffs fed to pregnant and non-pregnant sows. The six types of CSM were: two expelled CSMs with crude protein (CP) levels of 40.67% and 44.64%, and four solvent-extracted CSMs with CP levels of 45.18%, 51.16%, 56.44%, and 59.63%. Fourteen gestating sows (at the 4 th parity with body weights of 220.6 ± 18.4kg at days 30 of gestation) and 14 non-pregnant sows (after the 3 rd parity with body weights of 219 ± 14.6kg) were assigned to a replicated 7 × 3 Youden square design with seven diets and three periods. The seven diets included an entirely corn-based diet and six diets each containing 20.0% of the six CSMs tested. Each period included a 5-day acclimation to the experimental diets, followed by a 5-day period during which urine and feces were collected. Significant differences were found among the six CSM diets, regardless of reproductive stage, regarding: 1) the ATTD of neutral detergent fiber (NDF) (P < 0.05) and 2) the ATTD of dry matter (DM), organic matter (OM), and CP and the gross energy (GE) (P < 0.01). Non-pregnant sows had a greater ATTD of OM and CP (P < 0.01) compared with gestating sows. The digestible energy (DE) and metabolizable energy (ME) of the six CSM samples ranged from 12.48 to 17.15 MJ/kg and 11.35 to 15.88 MJ/kg, respectively, for non-pregnant sows, and from 12.86 to 16.41 MJ/kg and 12.43 to 14.72 MJ/kg, respectively, for gestating sows. However, the DE, ME, and ME:DE ratios of each CSM were similar between gestating and non-pregnant sows. DE and ME were negatively correlated with NDF and ADF, respectively, but were positively corrected with CP level (P < 0.01). Collectively, the DE, ME, and nutrient digestibility of CSM varied greatly according to the chemical compositions, and CSMs with higher protein and lower fiber levels had greater DE and ME levels.