Standardized Ileal Digestible Met Research Articles

144 Bioavailability of calcium salt of hydroxy analogue of methionine relative to DL-methionine to support growth performance of 11 to 20 kg pigs

Abstract Methionine (Met) is typically the third limiting AA in commercial swine diets and is commonly supplied as dry DL-Met (99% pure) or DL-Met hydroxy analogue. Data on the relative bioavailability (RBV) of calcium salt of hydroxy analogue of DL-Met (MHA-Ca; 84%) compared with DL-Met in weaned pigs is scarce. The objective of the experiment was to determine the RBV of MHA-Ca compared with DL-Met to support growth performance of 11 to 20 kg pigs. A total of 504 piglets [DNA x Pietrain pigs; approximately 42 d of age and 11 kg body weight (BW)] were used in two blocks of 252 pigs each with 6 pigs (3 entire males and 3 gilts) per pen and 12 replicate pens per treatment. Within each block, pigs were randomly allotted to 7 diets for 21 d. A basal diet (BD) was formulated to be adequate in all essential nutrients except for Met (0.22% standardized ileal digestible Met), which was 61% of the SID Met requirement of 0.36% recommended by NRC (2012) for 10 to 25 kg pigs. The Met-deficient BD was then supplemented with 3 graded levels of DL-Met (0.05, 0.10, and 0.15%) or MHA-Ca (0.077, 0.154, and 0.231%) at the expense of corn. Pigs had ad libitum access to feed (mash) and water. Individual pigs and pen feed disappearance were weighed on d 0 and d 21 to calculate average daily gain (ADG), average daily feed intake (ADFI) and feed conversion rate (FCR). On d 21, blood samples were collected from 1 pig per pen after 8 h fasting to determine total protein, albumin and glucose. Data were analyzed as a randomized complete block design using GLM procedure of SAS 9.4 (SAS Inst. Inc.). Orthogonal-polynomial contrasts were used to determine linear and quadratic effects of increasing levels of DL-Met and MHA-Ca, and the effect of Met sources. The final BW at d 21 and overall average daily gain (ADG; 375, 401, 429, 430, 402, 431, and 428 g/d for diets 1 to 7, respectively) increased linearly (P < 0.01) by graded additions with both Met sources. The ADFI was not different but the overall FCR (1.64, 1.55, 1.51, 1.45, 1.59, 1.46, and 1.50 for diets 1 to 7, respectively) improved linearly (P < 0.01) by supplementation with DL-Met or MHA-Ca. Pig performance responses (ADG, ADFI and FCR) was not different (P ≥ 0.15) when Met was supplemented in the Met-deficient diet at a DL-Met to MHA-Ca ratio of 65:100 on a product basis. Plasma concentrations of total protein, albumin and glucose on d 21 were not affected (P >0.05) by dietary treatments or Met sources. Based on ADG as a response of Met supplementation level, the linear and exponential regressions estimated the RBV of 64 and 65%, respectively for MHA-Ca relative to DL-Met (product-to-product basis) in 11 to 20 kg pigs.

PSII-13 Effects of Standardized Ileal Digestible Lysine, Fiber Level, and Amino Acid Ratios on Growth Performance of Nursery Pigs

Abstract An experiment was conducted to determine the interactive effects of standardized ileal digestible (SID) lysine, dietary fiber, and amino acid ratios on growth performance of nursery pigs. A total of 4,320 pigs (initial BW = 7.8 kg), placed in pens of 36 mixed sex pigs, were used in a 43-d trial. Treatments were arranged in a 2 × 2 × 2 factorial structure with two levels of SID Lys (1.15 or 1.38%), two levels of dietary fiber [control or high fiber (5% sugar beet pulp + 3.75% soy hulls)], and two amino acid ratio profiles [control (65% SID Thr:Lys, 58% SID Met+Cys:Lys, 67% SID Val:Lys, 55% SID Ile:Lys, and 18.5% SID Trp:Lys) or AA+ (5 percentage points greater than control ratios)] with 15 replicates per treatment. The experimental diets were fed from d 0 to 25 and a common corn-soybean meal-based diet was fed from d 25 to 43. Pigs were weighed on d 0, 25, and 43 to calculate ADG, ADFI, and G:F. Data were analyzed with the MIXED procedure in SAS. From d 0 to 25, there was a fiber × amino acid ratio interaction (P = 0.008) for ADFI, where pigs fed the high fiber diet had similar ADFI, regardless of AA ratios, but those fed control levels of fiber had reduced ADFI when fed AA+ ratios (Table 1). Similar interactions were also observed (P < 0.05) for overall (d 0 to 43) ADG, ADFI, and final BW. There were no other significant interactions (P > 0.05). As for main effects, pigs fed low Lys had reduced (P < 0.05) ADG, ADFI, and G:F. Feeding high fiber diets reduced (P < 0.05) G:F but did not impact (P > 0.05) ADG or ADFI. Pigs fed AA+ ratios had improved (P < 0.05) G:F but no evidence for differences (P > 0.05) for ADG or G:F was observed.

Effects of supplemental d-methionine in comparison to l-methionine on nitrogen retention, gut morphology, antioxidant status, and mRNA abundance of amino acid transporters in weanling pigs.

An N-balance experiment was conducted to test the hypothesis that d-Methionine (d-Met) has the same bioavailability and efficacy as l-Methionine (l-Met) when fed to weanling pigs. A Met-deficient basal diet containing 0.24% standardized ileal digestible (SID) Met was formulated. Six additional diets were formulated by adding 0.036%, 0.072%, or 0.108% d-Met or l-Met to the basal diet, and these diets, therefore, contained 77%, 87%, or 97% of the requirement for SID Met. Fifty-six barrows (10.53 ± 1.17 kg) were housed in metabolism crates and allotted to the seven diets with eight replicate pigs per diet. Feces and urine were collected quantitatively with 7-d adaptation and 5-d collection periods. Blood and tissue samples from pigs fed the basal diet and pigs fed diets containing 0.108% supplemental Met were collected on the last day. Results indicated that N retention (%) linearly increased (P < 0.01) as supplemental d-Met or l-Met increased in diets. Based on N retention (%) as a response, the linear slope-ratio regression estimated the bioavailability of d-Met relative to l-Met to be 101% (95% confidence interval: 57%-146%). The villus height and crypt depth in the jejunum were not affected by the Met level or Met source. Total antioxidant capacity or thiobarbituric acid reactive substance concentrations in plasma or tissue samples from pigs fed the control diet or diets containing 0.108% supplemental d-Met or l-Met were not different. Abundance of mRNA for some AA transporters analyzed in intestinal mucosa of pigs also did not differ. Therefore, it is concluded that d-Met and l-Met are equally bioavailable for weanling pigs.

Maintaining the same ratio between standardized ileal digestible methionine and cysteine do not affect its requirements for starting pigs

AbstractThis study aimed to determine the requirements of standardized ileal digestible (SID) methionine (Met) + cysteine (Cys) of 15–30 kg barrows, maintaining or increasing the 1:1 ratio between SID Met and SID Cys. Seventy crossbred barrows averaging 15.2 ± 0.54 kg of live weight were allotted in a randomized block design 2 × 3 + 1 factorial scheme, with five replicates and two animals per pen. Treatments consisted of maintaining or increasing the 1:1 ratio between SID Met and SID Cys, three levels of SID Met + Cys (5.8, 6.4 and 7.0 g/kg) and a basal diet containing the lowest SID Met + Cys level (5.2 g/kg), formulated to provide a 1:1 ratio of SID Met (2.6 g/kg) and SID Cys (2.6 g/kg). Performance, blood parameters, longissimus dorsi muscle depth, backfat thickness and S–S linkages in the bristles were evaluated. The best average daily gain was estimated at 6.61 g/kg of SID Met + Cys, without maintaining the 1:1 ratio between sulphur amino acids (SAA). The daily intake of SID Met + Cys increased due to dietary SID Met + Cys levels, maintaining or increasing the same ratio between SAA. Plasma glucose increased and total cholesterol decreased according to SID Met + Cys levels, without maintaining the same ratio between the SAA. The requirement of SID Met + Cys for 15–30 kg barrows was 6.61 g/kg (7.88 g/day) for an optimum average daily gain, with no need to maintain the same ratio between the SAA.

Dietary glycine equivalent and standardized ileal digestible methionine + cysteine levels for male broiler chickens fed low-crude-protein diets

This study was conducted to determine the optimum dietary glycine equivalent (Glyequi) level in low-crude-protein diets of 181 g·kg−1 containing varied concentrations of standardized ileal digestible (SID) methionine + cysteine (Met + Cys) for broiler chicks (1–21 d old). A total of 1275, 1-d-old Cobb-Vantress® male broilers were distributed in a 5 × 3 factorial arrangement with a completely randomized design of 15 treatments with five replicates of 17 birds each. Treatments consisted of five levels of dietary Glyequi (14.9, 16.4, 17.9, 19.4, and 20.6 g·kg−1) and three concentrations of SID Met + Cys (7.70, 9.0, and 10.3 g·kg−1). Interactions between Glyequi and SID Met + Cys levels were observed for feed:gain (P = 0.055) and breast meat yield (BMY) (P = 0.017). In 7.7 and 9.0 g SID Met + Cys·kg−1 diets, optimal feed:gain and increased BMY were observed at Glyequi levels not lower than 17.9 g·kg−1. In 10.3 g SID Met + Cys·kg−1 diet, a lower feed:gain was achieved at 19.4 g Glyequi·kg−1. Therefore, a minimum dietary level of 17.9 g Glyequi·kg−1 is needed to increase growth of broilers fed diets containing 7.7 or 9.0 g·kg−1 SID Met + Cys, whereas 19.4 g·kg−1 Glyequi is necessary in diets containing 10.3 g·kg−1 SID Met + Cys for optimum growth.

200 Reduced growth performance of pigs fed methionine deficient diet may be associated with their reduced muscle cell differentiation

Abstract Methionine (Met) is the second or third limiting AA in typical swine diets and plays important roles in promoting the growth, especially, the muscle growth of pigs. This research studied the effects of dietary Met restriction on growth performance and myogenic gene expression in growing pigs. Eight genes in two families, including myogenic regulatory factor family comprising myogenic differentiation 1 (MyoD1), myogenic factor 5 (Myf5), myogenin (MyoG) and myogenic factor 6 (Myf6), and myocyte enhancer factor 2 (Mef2) family comprising Mef2A, Mef2B, Mef2C and Mef2D, were selected for analysis. Individually penned barrows (crossbred, 23.6±2.4 kg) were randomly assigned to two dietary treatments. A basal diet (Diet 1; Met-deficient) was formulated to contain 0.22% standardized ileal digestible (SID) Met and 0.52% SID Met+Cys but to meet the NRC (2012) recommendations for other nutrients. Crystalline DL-Met was added to the basal diet to generate Diet 2 adequate in Met (0.37% SID Met, 0.67% SID Met+Cys). During the four-week ad libitum feeding trial, ADG, ADFI and G:F were measured. Immediately before and after the trial, muscle samples were collected from the longissimus dorsi using a standard biopsy protocol. Total RNA was extracted from the muscle samples (TRIzol Reagent; Invitrogen) and subjected to cDNA reverse-transcription (QuantiTect Reverse Transcription Kit; Qiagen). Transcribed cDNA were used for qPCR analysis (Rotor-Gene Q System; Qiagen). Comparative ΔΔCT method was used for quantitation. Data were analyzed with Student’s T-test. Pigs fed Diet 1 (vs. Diet 2) had a lower ADG and G:F (P&amp;lt; 0.01). Before the feeding trial, all the tested genes had comparable mRNA levels between the two treatments (P &amp;gt;0.17). After the trial, Diet 1 pigs showed tendency for lower levels of Myf6 and Mef2D mRNA (P&amp;lt; 0.09). These results suggest that the reduced ADG and G:F is associated with the possibly-reduced muscle cell differentiation in pigs fed Met-deficient diet.

210 Effects of D-methionine compared with L-methionine on N retention, gut morphology and antioxidant status of weaned pigs

Abstract A N-balance study was conducted to compare the effect of D-methionine (D-Met) or L-methionine (L-Met) supplementation on N balance, gut morphology and antioxidant status of weaned pigs. Fifty-six weaned barrows (10.5 ± 1.2 kg initial BW) were allotted to 7 diets in 2 blocks. A Met-deficient basal diet (BD; 0.24% standardized ileal digestible (SID) Met) but adequate in other AA, was supplemented with 3 graded levels (0.036, 0.072, and 0.108%) of D-Met or L-Met. After a 7-d adaptation, feces and urine were collected quantitatively for 5 d to determine N balance. At the completion of the experiment, blood samples were collected from all pigs. Pigs fed the BD and pigs fed the highest level of SID Met (0.34%) of both Met sources were euthanized and tissue samples from liver, kidney, muscle (longissimus dorsi), duodenal and jejunal mucosa were collected. N retention as % of N intake increased (P &amp;lt; 0.001; 67, 72, 73, 74, 71, 74, 74%, respectively) by graded supplemental level of D-Met or L-Met. However, there was no interaction between Met source and supplemental level for all N-balance metrics. Using a slope-ratio regression, the bioavailability of D-Met relative to L-Met was 100.1% (95% confidence intervals: 85-116%) based on N retention (% of N intake). Villus height and crypt depth in the duodenum and jejunum were not affected by Met sources. Pigs fed the D-Met diet had a greater (P &amp;lt; 0.05) total glutathione concentration in liver (4.9 vs. 1.5 µM) vs. BD. However, total antioxidant capacity and concentration of thiobarbituric acid-reactive substances in liver, muscle or plasma samples were not different among treatments. Supplementation with D-Met increased glutathione peroxidase activity in kidney (878 vs. 413 and 229 mU/mL; P &amp;lt; 0.05) compared with BD or L-Met diet, however, activity of glutathione reductase in liver and kidney were not affected by treatments. These data indicate that D-Met and L-Met are equally efficient to support N retention, intestinal morphology and oxidative status in weaned pigs.

PSVII-4 Optimal standardized ileal digestible lysine and methionine + cysteine to lysine ratio for 12 to 23 kg pigs fed antibiotic-free diets

Abstract Requirement of Lys is affected by lean gain capacity of the pigs. Methionine is the 3rd limiting AA in typical swine diets. In Exp. 1, 108 crossbred pigs (initial BW 11.8 kg) were assigned to 6 diets adequate in all AA but with increasing Lys content [0.90, 1.00, 1.10, 1.20, 1.30 and 1.40% standardized ileal digestible (SID) Lys] to determine the SID Lys requirement. In Exp. 2, 108 pigs (initial BW 11.9 kg) were assigned to 6 diets to determine the optimal SID Met+Cys:Lys ratio. Diets 1 to 5 were varied in SID Met+Cys:Lys (50, 55, 60, 65 and 70%) and 1.17% SID Lys (second limiting). Diet 6 was formulated to be adequate in all AA (1.25% SID Lys and 62% SID Met+Cys:Lys). There were 6 pens (2 barrows and 1 gilt) per treatment in both experiments and lasted for 21 d. Data were analyzed by ANOVA using the GLM procedure of SAS. In Exp. 1, increasing SID Lys increased the overall ADG and G:F (linear, P &lt; 0.001) and decreased plasma urea nitrogen (PUN; linear, P &lt; 0.001). Regression analysis estimated the SID Lys to be 1.36, 1.38 and 1.28% for ADG, G:F and PUN, respectively with an average SID Lys requirement of 1.34% for 12-23 kg pigs. In Exp. 2, increasing SID M+C:Lys ratio (diets 1 to 5) increased ADG and G:F (linear and quadratic, P &lt; 0.001) and decreased PUN (quadratic, P &lt; 0.001). Pigs fed a high Lys diet (diet 6) tended to have a lower PUN (P = 0.076) but performance was not affected. The regression models estimated the optimum SID M+C:Lys ratio to be 63.1 and 60.7% for ADG, and 62.5 and 61.1% for G:F, respectively while 62.9% SID M+C:Lys optimized PUN. On average, the optimal SID M+C:Lys ratio for 12-23 kg pigs was 62%.

Available energy and amino acid digestibility of yellow dent corn fed to growing pigs1.

Two experiments were conducted to determine the DE and ME as well as the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP and AA in corn fed to growing pigs. All corn was yellow dent corn collected from different areas in China. In Exp. 1, 60 crossbred barrows (Duroc × Landrace × Yorkshire; 40.7 ± 3.5 kg BW) were randomly allotted to 1 of 10 diets to determine the DE and ME of corns. Diets were formulated to contain 96.8% of 1 of the 10 corn samples and 3.2% of other microingredients. In Exp. 2, 11 crossbred barrows (Duroc × Landrace × Yorkshire; 30.5 ± 2.3 kg) fitted with a T-cannula at the distal ileum were assigned to a 6 × 11 Youden square design with 6 periods and 11 diets. Diets included a N-free diet based on cornstarch and sucrose and 10 test diets formulated with 96.6% 1 of the 10 corns as the sole source of AA. Chromic oxide (0.3%) was added to each diet as an indigestible marker for calculating the AA digestibility. On a DM basis, the starch, ether extract (EE), CP, NDF, and ADF contents of corns averaged 74.05% (69.98 to 78.59%), 3.83% (2.04 to 4.73%), 9.63% (7.74 to 10.43%), 10.80% (10.27 to 11.46%), and 2.27% (2.03 to 2.57%), respectively. The CV of EE, CP, and ADF was 22.59, 8.22, and 8.21%, respectively. The DE and ME of corns averaged 4,087 and 3,981 kcal/kg, respectively, and ranged from 3,999 to 4,161 kcal/kg and from 3,898 to 4,067 kcal/kg, respectively. The DE and ME values were positively correlated (P < 0.05) with the EE content. Optimal prediction equations of ME were ME = 940.35 + (0.72 × DE) + (21.88 × EE) (R2 = 0.94) or ME = 1,051.50 + (0.82 × DE) - (282.05 × ash) (R2 = 0.99). In Exp. 2, significant differences (P < 0.05) were observed in the SID of Arg, His, Phe, Ala, Pro, Cys, and Tyr. The SID of Lys (average 73.79%), Met (average 87.32%), and Thr (average 80.06%) ranged from 61.45 to 78.47%, from 74.09 to 90.91%, and from 79.19 to 85.79%, respectively. The standardized ileal digestible Met was positively correlated (P < 0.01) with the Met and CP contents. The obtained prediction equations were standardized ileal digestible Met = 31.34 + (3.43 × CP) + (116.04 × Met) and standardized ileal digestible Met = 104.92 + (294.71 × Met) - (7.03 × NDF). In conclusion, sources had an effect on the energy values and ileal digestibility of most AA in corn. The ME can be predicted by the DE combined with either the EE or ash content. The AA concentrations and SID of AA in corn varied largely.

Bioavailability of di-peptide dl-methionyl-dl-methionine in comparison to dl-methionine in weaned and growing pigs

The relative bioavailability (RBV) of a dipeptide dl-methionyl-dl-methionine (dl-Met-Met) was compared with dl-methionine (dl-Met) in growing pigs (experiment 1; N-balance study) and in weaned pigs (experiment 2; performance study). In experiment 1, 42 barrows with an initial body weight (BW) of 21.0 ± 1.37 kg were assigned to 7 dietary treatments with 6 replicate/pigs per treatment in a nitrogen (N) balance study to evaluate the RBV of dl-Met-Met to dl-Met. A basal diet (BD) was formulated to be adequate for all amino acids with the exception of Met + Cys which was 68% of the requirement [4.7 g/kg standardized ileal digestible (SID) Met + Cys; 11.5 g/kg SID Lys] for 20–25 kg pigs. Three graded levels of dl-Met (0.3, 0.6 and 0.9 g/kg) and dl-Met-Met (0.306, 0.612 and 0.919 g/kg) were supplemented to the BD to create diets 2–7. In experiment 2, a total of 189 weaned pigs (initial BW of 10.2 ± 0.98 kg) were assigned to 7 dietary treatments with 9 replicates/pens of 3 pigs per treatment. The dietary treatments consisted of a Met-deficient BD (5.3 g/kg SID Met + Cys; 13.0 g/kg SID Lys) and the same 3 graded levels of dl-Met and dl-Met-Met as in Exp. 1. In experiment 1, supplementation with dl-Met or dl-Met-Met linearly decreased (P ≤ 0.01; linear) urinary N excretion and increased (P ≤ 0.02; linear) N retained (g/day), N retention (% of intake and % of absorbed). However, there was no effect of Met sources on all N balance parameters. Based on the slope-ratio regression the RBV for dl-Met-Met compared to dl-Met was estimated 111% [95% confidence interval (CI): 63-158%] for N retained (g/d), 109% (95% CI: 57-160%) for N retention (% of intake) and 98% (95% CI: 43–154%) for N retention (% of absorbed) on an equi-molar basis. In experiment 2, the overall average daily gain (ADG) and gain:feed ratio (G:F) increased linearly (P < 0.01) by supplementation with dl-Met or dl-Met-Met. The average daily feed intake increased by supplementation with dl-Met (P = 0.02) and dl-Met-Met (P = 0.09). For ADG, the RBV for dl-Met-Met was estimated 104% (95% CI: 66-141%) on an equi-molar basis by the slope-ratio. Based on G:F, the RBV for dl-Met-Met was estimated 117% (95% CI: 61–174%) on an equi-molar basis. The results of both experiments indicate that the bioavailability dl-Met-Met is not different and at least equally bioavailable as dl-Met as a Met source for pigs.

Prediction of the concentration of standardized ileal digestible amino acids in distillers dried grains with solubles1

Values for the concentration of standardized ileal digestible (SID) CP, Lys, Met, Thr, and Trp from 34 sources of distillers dried grains with solubles (DDGS) were obtained from a series of 5 experiments with the objective of predicting the concentration of SID AA from physical and chemical assays. The concentration of NDF, ADF, hemicellulose, acid detergent insoluble CP (ADICP), and KOH soluble protein (SolCP) were measured and calculated in all DDGS sources. Likewise, particle size was measured and color of each source of DDGS was determined with a Minolta colorimeter and HunterLab spectrometer and was expressed as lightness (L*), redness (a*), and yellowness (b*). The HunterLab spectrometer also provided optical density that was recorded between 400 and 700 nm. Front face fluorescence was measured at 360 nm excitation and recorded from 380 to 600 nm. Multiple linear regression and principal components analyses were performed to predict the concentration of SID AA among DDGS sources, and predicted means as well as predicted residual sums of squares (PRESS) were calculated to estimate accuracy and precision of the model. Some correlations (P < 0.05) were observed between ADF, hemicellulose, ADICP, and SolCP with SID CP and AA but were generally low (r < 0.51). There was a greater association (R(2) = 0.40; P < 0.05) between L* and SID Lys among DDGS sources when L* was less than 50 than when samples had L* values greater than 50. In addition, a* was negatively correlated (P < 0.05) with SID CP (r = -0.41), Lys (r = -0.59), and Met (r = -0.50) whereas b* tended to be positively correlated (P < 0.10) with SID Lys (r = 0.31) and Trp (r = 0.30) and was correlated (P = 0.05) with SID Met (r = 0.43) and Thr (r = 0.36). There were no correlations between NDF or particle size with SID CP and AA. Optical density, along with CP, was highly predictive of SID Lys (R(2) = 0.97; PRESS = 0.05), Thr (R(2) = 0.94; PRESS = 0.06), and Trp (R(2) = 0.93; PRESS = 0.004) but not SID Met (R(2) = 0.39; PRESS = 0.12). Front face fluorescence was also highly predictive of SID Lys (R(2) = 0.99; PRESS = 0.07), Met (R(2) = 0.95; PRESS = 0.05), Thr (R(2) = 0.99; PRESS = 0.008), and Trp (R(2) = 0.99; PRESS = 0.006). In conclusion, correlations between ADICP, SolCP, NDF, particle size, and color measurements with SID AA concentrations were poor, but optical density and front face fluorescence methods appear to provide good predictions of SID AA concentrations in DDGS. However, these prediction equations need to be validated using samples of DDGS from a separate data set.

Growth performance, organ weights, and blood parameters of broilers fed diets containing expeller-extracted canola meal

A study was conducted to determine the effect of including expeller-extracted canola meal (EECM) in diets for broilers on performance, thyroid gland size, liver and kidney sizes, blood serum concentration of triiodothyronine and tetraiodothyronine, hemoglobin content in blood, hematocrit, and histology of liver and kidney. A total of 200 male broiler chicks (1 d old) were divided into 40 groups of 5 birds balanced for BW and fed 5 diets in a completely randomized design (8 groups/diet) from d 1 to 21 of age. The diets were a complete corn-soybean meal-based basal diet with 0, 10, 20, 30, or 40% of EECM. Diets were formulated to have the same ME, CP, Ca, nonphytate P, and standardized ileal digestible Met and Lys contents. The EECM contained (% of DM) 37.8% CP, 0.74% Met, 2.14% Lys, 1.62% Thr, 1.61% Val, and 7.64 μmol/g of glucosinolates. An increase in dietary level of EECM from 0 to 40% resulted in a linear decrease in feed intake (P < 0.001) by 4.8 g/21-d period for each 1% increase in EECM and in BW gain (P < 0.001) by 6.0 g/21-d period for each 1% increase in EECM. However, dietary EECM linearly increased liver weight relative to live BW (P < 0.001) and serum tetraiodothyronine concentration (P = 0.019). An increase in dietary level of EECM from 0 to 40% did not result in a significant increase in kidney weight relative to live BW. There was no effect of EECM on heart and thyroid gland weights relative to live BW or on the blood hemoglobin content, hematocrit, and serum triiodothyronine concentration. In conclusion, an increase in dietary level of EECM resulted in reduced growth performance and may interfere with liver function, likely because of increased dietary concentration of glucosinolates. Thus, the amount of EECM included in broiler diets should be based on the desired growth performance and the cost of the EECM.

Processing conditions affect nutrient digestibility of cold-pressed canola cake for grower pigs1

Cold-pressed canola cake is a coproduct of biodiesel production that contains more residual oil than expeller-pressed and solvent-extracted canola meal. Cold-pressed canola cake might be an attractive feedstuff for swine due to local availability from small plants. However, the nutritional quality and content of anti-nutritional factors of cold-pressed canola cake are poorly defined and vary with processing conditions. This experiment evaluated cold-pressed canola cake processed using 4 different conditions: a nonheated and heated barrel at slow and fast screw speed in a 2 × 2 factorial arrangement. Seven ileally cannulated barrows (26 kg of BW) were fed twice daily at 2.8 × maintenance diets containing either 44% of 1 of the 4 cold-pressed canola cake samples, expeller-pressed canola meal, canola seed, or an N-free diet in a 7 × 7 Latin square. The objectives were to measure the energy and AA digestibility and to calculate standardized ileal digestible (SID) AA and NE content. Each 9-d experimental period consisted of a 5-d diet adaptation, followed by 2-d feces and 2-d ileal digesta collections, and 7 observations per diet were obtained. Cold-pressed canola cake contained 41% CP, 16% ether extract, and 5 µmol of total glucosinolates/g (DM basis). Both apparent ileal digestibility (AID) and total tract energy digestibility of energy in cold-pressed canola cake was 36% greater (P < 0.05) in heated vs. nonheated conditions and 8% greater (P < 0.05) in fast vs. slow screw speed without interaction, indicating that heat enhanced energy digestibility. The AID of energy of cold-pressed canola cake was 13 and 118% greater (P < 0.01) than expeller-pressed canola meal and canola seed, respectively. Heat and speed interacted (P < 0.05) for SID of AA of test ingredients, but effects were not consistent among AA. The DE and calculated NE content of cold-pressed canola cake was 0.73 and 0.52 Mcal/kg greater (P=0.001; DM basis), respectively, than expeller-pressed canola meal and did not differ from canola seed. Cold-pressed canola cake averaged 4.17 Mcal of DE/kg, 2.84 Mcal of NE/kg, 0.87% SID Lys, 0.46% SID Met, and 0.79% SID Thr (DM basis). In conclusion, processing conditions greatly affected the digestible nutrient content of cold-pressed canola cake. Content of residual ether extract was an important determinant of the energy value of cold-press canola cake, whereas residual glucosinolates did not seem to hamper nutrient digestibility.