Variations in the chemical composition and standardized ileal digestibility of amino acids in eight genotypes of triticale fed to growing pigs.

The study was conducted to determine the chemical composition, physical characteristics, and standardized ileal digestibility (SID) of CP and AA of 8 currently available genotypes of triticale fed to growing pigs. The genotypes included Grenado, Cando, Agostino, Massimo, Tarzan, HYT Prime, SW Talentro, and Cultivo. Eight barrows with an initial BW of 31 ± 2 kg were fitted with simple T-cannulas at the distal ileum and allotted to an 8 × 8 Latin square design with 8 periods of 7 d each and 8 assay diets. The N-free method was used to determine basal ileal endogenous CP and AA losses. The 8 assay diets contained 1 of 8 triticale genotypes as the sole source of CP and AA. The triticale genotypes were grown under identical environmental conditions on the same site. Among the 8 genotypes, contents of CP ranged from 104.7 to 118.1 g/kg (as-fed basis). The content of total nonstarch polysaccharides and NDF ranged, on an as-fed basis, from 84.6 to 99.5 g/kg and from 88.4 to 149.0 g/kg, respectively. Among the 8 genotypes, SID of CP ranged from 81% in Grenado to 85% in Massimo and Tarzan. The SID of CP and AA did not differ among triticale genotypes except for SID of Arg, Glu, and Gly ( < 0.05). The mean SID of CP, Lys, Met, and Trp was 4, 4, 4, and 1 percantage units less and SID of Trp was 5 percantage units greater compared with values in current feed tables. Among the 8 triticale genotypes, standardized ileal digestible content (cSID) of CP followed total CP content and ranged from 84.8 to 98.7 g/kg (as-fed basis), with the lowest ( < 0.001) values for Grenado and the greatest ( < 0.001) values for SW Talentro and Cultivo. For CP and most AA, cSID linearly decreased as the content of total, soluble, and insoluble ß-glucans increased ( < 0.05) in the 8 genotypes of triticale. There was a positive correlation between thousand seed weight and cSID of CP and most AA ( < 0.01). These variables may help to predict cSID in triticale batches, whereas other nutrients are not suitable due to their low variation among the 8 genotypes. The present study provides data on chemical composition, physical characteristics, and SID of CP and AA of 8 triticale genotypes grown under similar conditions. However, as most of the present SID values are less than those in feed tables, future research is warranted to elaborate whether these differences are caused by experimental conditions or reflect a consistent decrease that needs to be accounted for in feed tables.

Influence of wet heating and autoclaving on chemical composition and standardized ileal crude protein and amino acid digestibility in full-fat soybeans for pigs.

One batch each of eight full-fat soybeans (FFSB) was used to determine the effect of different heat treatments including wet heating (WH) and autoclaving (AC) on chemical composition and standardized ileal digestibility (SID) of CP and AA in growing pigs. The raw FFSB (K0) were either treated by WH at 80°C for 1 min (K1), at 100°C for 6 min (K2), or at 100°C for 16 min (K3). Thereafter, these batches were expanded at 125°C for 15 s. A further heat treatment included AC at 110°C for 15 (Z1), 30 (Z2), 45 (Z3), or 60 (Z4) min of FFSB that were subjected to the same WH treatment as K3. Diets were formulated to contain the respective FFSB as the sole source of CP and AA. A N-free diet was used to measure basal endogenous losses of CP and AA in an additional period at the end of the experiment. Eight ileally cannulated pigs (28 ± 1 kg) were allocated to a row-column design with 8 diets and 6 periods of 7 d each. An increase in the duration of WH had no effect on contents of AA (% of CP) and NDF, but NDIN contents linearly increased ( < 0.05) with increasing time for WH. Autoclaving resulted in a linear decrease ( < 0.05) of trypsin inhibitor activity (TIA), contents of Arg, Leu, Ala, Asp, Cys, and Gly as well as Lys to CP ratio (Lys:CP), reactive Lys to CP ratio (rLys:CP), and in an increase ( < 0.05) in contents of NDF and NDIN. There was a quadratic response ( < 0.05) of SID of CP and AA as time for WH at 100°C increased from 0 (K0) to 6 (K2) up to 16 (K3) min. Moreover, a quadratic response ( < 0.05) to increasing time of AC was observed for SID of Arg, Phe, and Pro. The SID of CP and all indispensable AA showed a quadratic response ( < 0.05) to decreasing TIA, urease activity, protein solubility in 0.2% potassium hydroxide, protein dispersibility index, Lys:CP, (lightness), and to increasing NDIN and (redness). In addition, there was a linear increase ( < 0.05) in SID values with decreasing rLys:CP and increasing NDF contents. In conclusion, WH proved to be suitable for increasing SID values. Further improvement of SID of most AA could be achieved on additional AC treatment from Z1 to Z3, however, it needs to be considered, if the observed increase due to AC is cost effective in view of the additional production costs. Several chemical and physical parameters can be used in the feed industry for quality control purposes to predict the extent of heat damage on SID of CP and indispensable AA in FFSB.

Chemical composition and standardized ileal amino acid digestibility of eight genotypes of rye fed to growing pigs.

A study with growing pigs was conducted to determine the chemical composition, physical characteristics, and standardized ileal digestibility (SID) of CP and AA of 8 rye genotypes that have recently been added to the German Descriptive Variety List. Eight barrows with an initial BW of 24 ± 2 kg were fitted with T-cannulas at the distal ileum and allotted to an 8 × 8 Latin square design with 8 periods of 6 d each and 8 pigs receiving 8 different diets. The N-free method was used to determine the basal ileal endogenous CP and AA losses. The 8 assay diets contained 1 of 8 rye genotypes (Guttino, Palazzo, Visello, Bellami, Dukato, Conduct, Helltop, and Dankowski Diament) as the sole source of CP and AA. The rye genotypes were grown under identical environmental conditions on the same site. Among the 8 rye genotypes, contents of CP ranged from 9.5 to 11.2% (as-fed basis) and contents of total nonstarch polysaccharides (NSP) ranged from 10.7 to 12.9% (as-fed basis). Arabinoxylan (AX) constituted the major NSP fraction, with values ranging from 6.5 to 7.6% (as-fed basis). Among the 8 rye genotypes, starch contents ranged from 55.7 to 57.5% (as-fed basis). The SID of CP in the 8 rye genotypes ranged from 70 to 74%. The SID of Cys in genotypes Visello, Bellami, Dukato, and Dankowski Diament was lower ( < 0.05) when compared with Palazzo, Conduct, and Helltop. For all other AA, SID in the 8 rye genotypes did not differ. The standardized ileal digestible content (cSID) of CP was greatest ( < 0.001) in genotype Dankowski Diament (8.1%, as-fed basis) and lowest ( < 0.001) in genotype Guttino (6.9%, as-fed basis). Genotype Guttino had the lowest ( < 0.05) cSID of AA among all rye genotypes, except for Trp, Gly, and Pro. For Thr, Ala, and Gly, there were no differences in cSID among the 8 rye genotypes. For CP and most AA, cSID decreased as contents of total and insoluble ß-glucan ( < 0.05), total AX, and soluble NSP increased ( < 0.05). The results of the present study provide a comprehensive database on chemical composition, physical characteristics, and SID of CP and AA of 8 rye genotypes grown under same conditions. However, as present SID values of these recently introduced genotypes are lower compared to values in feed tables, adjustments are possibly required to minimize the risk of overestimating the actual protein value of rye for pigs.

Variability in amino acid digestibility of triticale grain from diverse genotypes as studied in cecectomized laying hens.

Triticale, an anthropogenic hybrid grain, is increasing in importance as a feed grain for laying hens. However, our limited knowledge of its nutritional qualities and their impact on hen performance prevents optimization of its use. The present study investigated the digestibility of amino acids ( AA: ) in triticale grain in laying hens, and additionally examined relationships between AA digestibility and chemical and physical characteristics of the grain. Twenty genotypes of triticale were grown under standardized agronomic and environmental conditions and were characterized according to their physical properties (thousand-seed weight, test weight, falling number, extract viscoelasticity), chemical composition (proximate nutrients, non-starch polysaccharides, AA, minerals, inositol phosphates) and gross energy concentration. Additionally, the in vitro solubility of nitrogen was determined. The animal trial comprised 4 Latin Squares (6 × 6) distributed among 2 subsequent runs. Twelve cecectomized LSL-Classic hens were individually housed in metabolism cages and either fed a basal diet containing 500 g/kg cornstarch or one of 20 triticale diets, each replacing the cornstarch with one triticale genotype, for 8 d. During the last 4 d, feed intake was recorded and excreta were collected quantitatively. Amino acid digestibility of the triticale genotypes was calculated by linear regression. The digestibility of all AA differed significantly between the 20 genotypes, including Lys (digestibility range 68 to 80%), Met (77 to 86%), Thr (68 to 78%) and Trp (74 to 83%). However, AA digestibility only correlated with characteristics of the grain in few cases, without a consistent pattern among AA. Equations to predict AA digestibility based on the grain's physical and chemical characteristics were calculated by multiple linear regression. The explanatory power (adjusted R2;) of these prediction equations was below 0.7 for most AA and thus not sufficiently precise to be suitable for practical application. In conclusion, AA digestibility of triticale grain is high overall in laying hens but varies significantly between crop genotypes. This variation could not be well explained by physical and chemical characteristics of the grain.

Standardized ileal digestibility of amino acids in eight genotypes of barley fed to growing pigs.

To determine chemical composition, physical characteristics and standardized ileal digestibility (SID) of CP and amino acids (AA) in eight current hulled barley genotypes, an experiment with growing pigs has been conducted. These genotypes included Yool, Campanile, Lomerit, Travira, Anisette, Canberra, Metaxa and Fridericus. Growing barrows with an average initial BW of 30±2 kg were surgically fitted with simple T-cannulas at the distal ileum, and allotted to an 8×9 Youden square design with eight periods of 6 days each and nine pigs. Barley was the sole dietary source of CP and AA. On average, the eight genotypes contained on as-fed basis 10.7% CP, 15.2% total non-starch polysaccharides (NSP), 17.1% NDF and 4.1% ß-glucan, and had a mean test weight (TW) of 72.2 kg/hl. The SID of CP in the barley genotypes varied from 69% to 74%, and was greater (P<0.01) for genotypes Travira, Anisette and Metaxa compared to Yool and Campanile. Standardized ileal digestibility of Lys, Met and Trp (P<0.05) but not of Thr differed between genotypes. Moreover, barley genotypes differed in their standardized ileal digestible content (cSID) of CP and AA. Furthermore, SID and cSID of CP and most AA linearly decreased (P<0.05) with increasing NDF and total sugar content. Standardized ileal digestibility of CP and some AA and cSID of CP and most AA decreased linearly with increasing TW (P<0.05). Additionally, SID and cSID of CP and AA of most barley genotypes were lower when compared to tabulated values. In conclusion, a comprehensive database on chemical composition and SID of CP and AA in eight current barley genotypes has been made available. However, as present SID values are lower compared to feed tables, adjustments are required to minimize the risk of overestimating the actual protein value of barley for pigs.

Effect of processing of rapeseed under defined conditions in a pilot plant on chemical composition and standardized ileal amino acid digestibility in rapeseed meal for pigs.

Five rapeseed meals (RSM) were produced from a single batch of rapeseed in a large-scale pilot plant under standardized conditions. The objective was to evaluate the effect of residence time in the desolventizer/toaster (DT) on chemical composition and standardized ileal digestibility (SID) of AA in RSM. Four RSM, with 48, 64, 76, and 93 min residence time and using unsaturated steam in the DT, referred to as RSM48, RSM64, RSM76, and RSM93, respectively, and 1 low-glucosinolate RSM, which was subjected to sequential treatment with unsaturated steam, saturated steam, and dry heat in the DT, referred to as low-GSL RSM, were assayed. Six barrows (average initial BW = 22 ± 1 kg) were surgically fitted with a T-cannula at the distal ileum. Pigs were allotted to a 5 × 6 row × column design with 5 diets and 5 periods. The 5 RSM were included in a cornstarch-casein-based basal diet. In addition, basal ileal endogenous losses and SID of AA originating from casein were determined at the conclusion of the experiment in 2 additional periods by means of the regression method and using 3 graded levels of casein. The SID of AA in the 5 RSM was determined in difference to SID of AA originating from casein. The glucosinolates (GSL) were efficiently reduced, whereas NDF, ADF, ADL, and NDIN contents increased and reactive Lys (rLys) and Lys:CP ratio decreased as the residence time in the DT was increased from 48 to 93 min. The SID of most AA in RSM linearly decreased (P < 0.05) as the residence time in the DT increased from 48 to 93 min. Moreover, there was a linear decrease (P < 0.05) in SID of AA with increasing NDF, ADF, ADL, and NDIN contents in these RSM, whereas SID of AA linearly decreased (P < 0.05) with decreasing levels of GSL and rLys and a decreasing Lys:CP ratio. The decrease (P < 0.05) in SID of AA amounted from 3 up to 6 (percentage units) for most AA, except for SID of Cys and Lys, which decreased by 10 and 11%-units (P < 0.05), respectively, as the residence time in the DT was increased from 48 to 93 min. The SID in low-GSL RSM was for CP and most AA similar to RSM93 but lower ( < 0.05) compared to RSM48. It can be concluded that time and energy-intensive heat treatment results in lower contents of SID AA in RSM together with a reduction in GSL levels. The feed industry would most likely benefit from a rapid and accurate prediction of SID of AA, for example, based on content of NDIN, GSL, rLys or on Lys:CP ratio, in different batches of RSM used for feed manufacturing.

Standardized ileal digestibility of amino acids in eight genotypes of soft winter wheat fed to growing pigs.

A study with growing pigs was conducted to determine the chemical composition and standardized ileal digestibility (SID) of CP and AA of 8 wheat genotypes that have recently been added to the German Descriptive Variety List. These genotypes included Tabasco, KWS Erasmus, Tobak, Skalmeje, Mulan, Event, Tommi, and Adler. The 8 genotypes were grown under identical environmental conditions on the same site, and they were harvested and processed under the same conditions. Nine barrows with an initial BW of 32 ± 2 kg were surgically fitted with simple ileal T-cannulas and allotted to a row-column design with 9 pigs and 8 periods of 6 d each. Wheat was the sole dietary source of CP and AA. Among the 8 wheat genotypes, contents of CP ranged from 10.9 to 13.3% (as-fed basis), whereas contents of total nonstarch polysaccharides ranged from 8.0 to 9.4% (as-fed basis). The SID of CP in the 8 genotypes ranged from 83 to 87%, with greatest ( = 0.01) values for Event and lowest ( = 0.01) for all other wheat genotypes. Intermediate SID of CP values were obtained for Adler and KWS Erasmus. For Lys, greater ( < 0.05) SID was observed in Adler (73%) and KWS Erasmus (74%) in comparison to Tommi, Tobak, and Mulan (69%). Adler had greater SID of Met (88%; = 0.01) when compared to Tabasco (86%); Tobak, Skalmeje, and Mulan (85%); and Tommi (84%). Among the 8 wheat genotypes, standardized ileal digestible content (cSID) of CP followed total CP content and ranged from 9.1 to 11.3% (as-fed basis). Standardized ileal digestible content of both CP and AA were greater ( < 0.001) in Adler compared to all other genotypes. For most AA, Tabasco had the lowest ( < 0.001; except for His, Trp, Asp, and Cys) cSID values of all wheat genotypes. The cSID of CP decreased ( < 0.001) as the starch content in the 8 wheat genotypes increased, but cSID of CP increased ( < 0.001) as the CP content in the 8 genotypes increased. Because SID and cSID of CP and most AA increased ( < 0.05) with lower test weight and falling number, these variables may aid to predict SID and cSID in wheat batches, whereas other nutrients such as fiber fractions are not suitable due to low variation among the 8 genotypes. The present study provides a comprehensive database on nutritional composition and SID of CP and AA of 8 wheat genotypes grown under identical conditions. Because the SID values in these genotypes are lower when compared to literature data, digestibility values in actual feed tables for wheat may overestimate their protein values and need to be updated.

Effect of particle size and heat treatment of soybean meal on standardized ileal digestibility of amino acids in growing pigs.

A study with growing barrows was conducted to evaluate of variations in particle size and degree of heat treatment during processing on standardized ileal digestibility (SID) of AA in soybean (Glycine max) meal (SBM). A commercial SBM batch was visually identified as being overtoasted due to its brownish color and was separated into small and large particles using a 1-mm sieve. In addition, 3 SBM were produced from 1 batch of soybean and exposed to different processing conditions (temperature and direct steam contact) referred to as mild (105°C; 34 min), medium (115°C; 45 min), and strong (139°C; 7 min). In total, 5 SBM-corn (Zea mays) starch-based diets were formulated to contain SBM as the sole protein source. This experiment was conducted according to a 6 × 6 Latin square design using 6 barrows (23 kg initial BW) fitted with a T-cannula at the distal ileum. With increasing particle size, SID of His and some dispensable AA increased (P < 0.05). Lower SID values in small compared to large SBM particles indicate more pronounced heat damage possibly due to increased surface area. The SID of CP and AA was lowest in the mild, intermediate in the strong, and highest in the medium toasted SBM (P < 0.001). These differences in SID are reflected in varying contents of trypsin inhibitors, Lys, reactive Lys, and NDF. In conclusion, both differences in particles size and variations in thermal processing conditions of SBM may affect SID of CP and AA.