Effects of keratinase supplementation of corn-soybean meal based diets on apparent ileal amino acid digestibility in growing pigs and serum amino acids,cytokines, immunoglobulin levels and loin muscle area in nursery pigs

Two experiments were conducted to evaluate effects of keratinase for growing and nursery pigs. In Exp. 1, six pigs (32.3 ± 2.8 kg body weight), fitted with a simple T-cannula at the distal ileum, were assigned to one of two 3 × 3 Latin squares involving three periods and three diets including a basal diet and the same diets supplemented with 0, 0.05 or 0.1% keratinase. Dietary keratinase supplementation increased the apparent ileal digestibility of crude protein (CP), arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, alanine, glutamic acid and proline (p < 0.05). Digestibility coefficients did not differ between pigs fed 0.05 and 0.1% keratinase. In Exp. 2, 24piglets weaned at 30 ± 2 d of age were used in a 2 × 2 factorial design experiment with two CP concentrations (19 vs. 22%) and two levels of keratinase supplementation (0 vs. 0.05%). Keratinase supplementation increased (p < 0.05) average daily gain, serum arginine concentration and loin muscle area but decreased (p < 0.05) serum interleukin-10 concentrations. The reduction in dietary CP level decreased (p < 0.05) serum urea nitrogen concentrations, isoleucine, serine and proline concentrations, but increased serum arginine concentrations. Few interactions between keratinase supplementation and dietary CP concentration were observed. This study indicated that dietary keratinase supplementation improved apparent ileal amino acid digestibility for growing pigs and had a positive effect on weight gain, immune response and loin muscle area for nursery pigs.     

Effect of microbial phytase on apparent ileal amino acid digestibility of phosphorus-adequate diets in growing pigs

Six ileally cannulated pigs (mean initial body weight 34.8 kg) were used to study the effect of microbial phytase on apparent ileal digestibility of P, total N and amino acids. Three P-adequate diets (digestible P concentration 2.3 g kg(- )l) containing barley (B), soyabean meal (S) or a mixture of the two (BS) with or without phytase supplement (1000 FTU x kg(-1)) were fed to pigs using a 6 x 6 Latin square design. The addition of phytase increased (p < 0.05) apparent ileal P digestibility of diets B, S and BS by 16.5, 19.2 and 19.2%, respectively. There was no effect of phytase on the ileal digestibility of total N. Apparent ileal digestibility of amino acids tended to increase in the BS diet supplemented with phytase (mean improvement of 2.2%); but no significant difference was found for any amino acid as compared with the unsupplemented diet. To asses the additivity of apparent amino acid digestibility, the determined values for the BS diet were compared to those calculated from digestibilities found in diets B and S. There were no significant differences between the determined and calculated values. It is concluded that the addition of microbial phytase to P-adequate diets does not affect ileal amino acid digestibility in growing pigs and that the apparent amino acid digestibility values determined in single ingredients may be additive when included into a complex diet.     

Evaluating standardized ileal digestibility of amino acids in growing pigs

The ileal digestibility coefficient (CSID) of amino acids (AA) and crude protein (CP) in 40 feedstuffs for growing pigs were determined with the protein-free (PF) and enzyme-hydrolyzed casein (EHC) methods. The 40 feedstuffs that were used earlier were 10 samples of cereals and cereal by-products, 12 samples of legumes, 6 samples of animal protein feedstuff and 12 samples of oil seed meals. Six growing pigs (initial body weight of 35 ± 1.5 kg), fitted with T-cannula at the terminal ileum, were randomly allocated to either a PF or a EHC diet according to a crossover design during two ileal digesta collection periods. In each period, pigs were adjusted to the experimental diets for 5 days. On days 6 and 8, ileal digesta were collected continuously for 24 h to determine ileal endogenous AA and CP losses. Pigs fed the EHC diet had a higher ileal flow of endogenous CP and of most of AA (P<0.05) than pigs fed the PF diet. Among the ileal endogenous AA flows (g/kg dry matter intake for pigs), methionine excretion was the lowest in pigs (0.09 and 0.25 g/kg dry matter intake) fed the PF and EHC diet, respectively, whereas glutamate (1.83 g/kg dry matter intake) and proline (1.22 g/kg dry material intake) excretion were the highest in pigs fed the EHC and the PF diet, respectively. Endogenous losses of CP and AA determined in the current study and previously published data on apparent ileal digestibility [Yin, Y.L., Huang, R.L., Zhong, H.Y., Chen, C.M., Li, T.J., Pan, Y.F., 1993. Nutritive value of feedstuffs and diets for pigs: 1. Chemical composition, apparent ileal and fecal digestibilities. Anim. Feed Sci. Technol. 44, 1–27] were used to calculate CSID coefficients. For most cereals and cereal by-products, the CSID coefficients of CP determined by the EHC method were higher than those determined by the PF method. Arginine, lysine, methionine, threonine, valine, alanine, aspartate, glutamate, glycine, proline and serine in some cereals and cereal by-products; methionine, valine, alanine and proline in some legumes; and methionine, alaline and proline in some oilseed meals had higher CSID determined by the EHC method than the PF method indicating that there are methodological differences when evaluating the CSID of feed ingredients.     

Meta-analysis of the amino acid digestibility of oilseed meal in growing pigs

Oilseed meal is an important source of essential amino acids (EAA) for livestock production. It is the second most important ingredient in pig feed after grains. Optimal use of these ingredients requires precise knowledge of amino acid standardized ileal digestibility (SID), which may vary depending on several factors including botanical variety or processing treatments. A meta-analysis was performed in order to derive models for predicting the SID of soybean, cotton and rapeseed meal EAA, based on chemical composition data such as CP, total concentration of each EAA and fibre (crude fibre, ADF and NDF) content. A database of 47 references (224 experimental treatments) was built. A model incorporating processing method of the meals (e.g. cold pressed, expeller pressed, solvent extracted), experimental surgical procedure (T-cannula, re-entrant cannula, post valve T-cannula and ileo-rectal anastomosis) and pig growth stage (BW⩽ or ⩾25 kg) was tested. Results indicated that neither processing nor BW affected EAA SID. NDF was the best predictor of SID (R²=0.944, 0.836, 0.779, 0.899 and 0.814, respectively, for Lys, Met, Thr, Trp and Val). The total EAA content was the best predictor of digestible content (g/kg diet) for each EAA (R²=0.990, 0.985, 0.977, 0.985 and 0.978, respectively, for Lys, Met, Thr, Trp and Val). This study shows that routine chemical analyses may be used to predict EAA digestibility with satisfactory accuracy.     

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% β-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.     

Effects of ileal endogenous nitrogen losses and dietary amino acid supplementation on nitrogen retention in growing pigs

The relationship between ileal endogenous nitrogen (N) losses and N retention was studied in two experiments with growing pigs of 40 to 60 kg. In Experiment 1, 13 ileal cannulated castrated males were fed diets based on maize starch, containing either soyabean meal (SBM) with a low trypsin inhibitor activity (TIA), a mixture of toasted and untoasted soyabean meal with a high TIA (mSBM), a commercial batch of peas, or rapeseed expeller cake (RC). Ileal endogenous N recovery was measured using the ¹⁵N-isotope dilution technique. Apparent ileal digestibility of crude protein (CP) for the SBM, mSBM, pea and RC diets were 82.8, 72.0, 76.7 and 68.7% (P < 0.05). True ileal CP digestibility for the diets was 96.5, 93.0, 94.0 and 87.5% (P < 0.05), and the recovery of ileal endogenous N was 3.08, 6.01, 4.55 and 5.36 g/kg DMI (P < 0.05). In Experiment 2, sixteen castrated males were used to determine N retention, using almost similar diets as in Experiment 1. The diets contained either SBM, mSBM or peas and were balanced for the contents of apparent ileal digestible (ID) CP (96 g/kg) and ID essential amino acids (EAA; at least 85% of requirement values). The fourth treatment was a diet with mSBM as protein source, but supplemented with EAA to the level of 95% of the requirement values (diet mSBMs). Apparent faecal CP digestibility for the SBM, mSBM, pea and mSBMs diets was 88.6, 87.2, 86.1 and 86.0% (P < 0.05). Urinary N excretion and N retention for these treatments were 0.39, 0.59, 0.40, 0.53 (P < 0.05) and 0.87, 0.80, 0.85, 0.84 g/kg^0.75/day (P < 0.05), respectively. Utilization of dietary ID N for N retention were 79.8, 73.3, 78.2 and 77.6% (P < 0.05), respectively. The study showed that increased ileal endogenous N losses are associated with higher losses of urinary N and with a lower N retention. Supplementation of extra essential AA to a diet causing a relatively high flow of ileal endogenous N, may compensate for the lower N utilization under these conditions, and thus limit effects on N retention.     

Effects of dietary protein and amino acid levels on the expression of selected cationic amino acid transporters and serum amino acid concentration in growing pigs

The absorption of lysine is facilitated by leucine, but there is no information regarding the effect of crude protein, lysine and leucine levels on the expression of cationic amino acid transporters in pigs. Therefore, an experiment was conducted with 20 pigs (14.9 +/- 0.62 kg initial body weight) to evaluate the effect of two protein levels, and the content of lysine, threonine, methionine and leucine in low crude protein diets on the expression of b(0,+) and CAT-1 mRNA in jejunum, Longissimus dorsi and Semitendinosus muscles and serum concentration of amino acids. Treatments were as follows: (i) wheat-soybean meal diet, 20% crude protein (Control); (ii) wheat diet deficient in lysine, threonine and methionine (Basal diet); (iii) Basal diet plus 0.70% L-lysine, 0.27% L-threonine, 0.10% DL-methionine (Diet LTM); (iv) Diet LTM plus 0.80% L-leucine (Diet LTM + Leu). Despite the Basal diet, all diets were formulated to meet the requirements of lysine, threonine and methionine; Diet LTM + Leu supplied 60% excess of leucine. The addition of lysine, threonine and methionine in Diet LTM increased the expression of b(0,+) in jejunum and CAT-1 in the Semitendinosus and Longissiums muscles and decreased CAT-1 in jejunum; the serum concentration of lysine was also increased (p < 0.01). Further addition of L-leucine (Diet LTM + Leu) decreased the b(0,+) expression in jejunum and CAT-1 in the Longissimus dorsi muscle (p < 0.05), increased the serum concentration ofleucine and arginine and decreased the concentration of isoleucine (p < 0.05). Pigs fed the Control diet expressed less b(0,+) in jejunum, and CAT-1 in the Semitendinosus and Longissiums muscles expressed more CAT-1 in jejunum (p < 0.05) and had lower serum concentration ofisoleucine, leucine and valine (p < 0.05), but higher lysine concentrations (p < 0.01) than those fed Diet LTM. These results indicated that both, the level and the source of dietary amino acids, affect the expression of cationic amino acid transporters in pigs fed wheat-based diets.     

Dietary supplementation with Chinese herbal powder enhances ileal digestibilities and serum concentrations of amino acids in young pigs

This study was designed to determine the effect of ultra-fine Chinese herbal powder as a dietary additive on serum concentrations and apparent ileal digestibilities (AID) of amino acids (AA) in young pigs. In Experiment 1, 60 Duroc x Landrace x Yorkshire piglets weaned at 21 days of age were randomly assigned to one of three treatments, representing supplementation with 0 or 2 g/kg of the powder, or 0.2 g/kg of colistin (an antibiotic) to corn- and soybean meal-based diets (n = 20 per group). Blood samples from five piglets per group were collected on days 7, 14, and 28 to determine serum AA concentrations. In Experiment 2, 12 barrows with an average initial body weight of 7.64 kg were randomly assigned to one of the three dietary treatments, followed by surgical placement of a simple T-cannula at the terminal ileum. All of the diets contained 0.1% titanium oxide as a digestibility marker. The samples of terminal ileal digesta were collected on day 7 for determining AID of AA. Results show that dietary supplementation with the herbal powder increased (P < 0.05) serum concentrations and AID of most AA by 10-50% and 10-16%, respectively. As an indicator of improved intestinal function, AID values of calcium were also enhanced in piglets supplemented with the herbal powder. Dietary supplementation of colistin increased serum concentrations and AID values of some AA by 8-44% and 10-15%, respectively, in comparison with the non-supplemented group. These novel findings demonstrate that the herbal powder can enhance the digestibility of dietary protein and the intestinal absorption of AA into the systemic circulation in post-weaning pigs, therefore providing a new mechanism for its growth- and immunity-promoting efficacy.     

Effects of graded dose dietary supplementation of Piper betle leaf meal and Persicaria odorata leaf meal on growth performance,apparent ileal digestibility,and gut morphology in broilers

Due to antimicrobial resistance and the public health hazard of antibiotic growth promoters, there is a grave need to find potential alternatives for sustainable poultry production. Piper betle (PB) and Persicaria odorata (PO) are herbs, which have been reported for antimicrobial, antioxidant, and anti-inflammatory properties. The present study aimed to estimate the influence of different dose supplementation of Piper betle leaf meal (PBLM) and Persicaria odorata leaf meal (POLM) on growth performance, ileal digestibility and gut morphology of broilers chickens. A total of 210 one day-old broiler chicks were randomly grouped into 7 treatments, and each treatment group has 3 replicates (n = 10) with a total number of 30 chicks. The treatments included T₁ control (basal diet (BD) with no supplementation), T₂ (BD + 2 g/kg PBLM); T₃ (BD + 4 g/kg PBLM), T₄ (BD + 8 g/kg PBLM), T₅ (BD + 2 g/kg POLM), T₆ (BD + 4 g/kg POLM), T₇ (BD + 8 g/kg POLM). Growth performance, gut morphology and ileal digestibility were measured. Except for T₄ (8 g/kg PBLM), graded dose inclusion of PBLM and POLM increased (P < 0.05) the body weight gain (BWG), positively modulated the gut architecture and enhanced nutrient digestibility in both stater and finisher growth phases of broiler chickens. Birds fed on PBLM 4 g/kg (T₃), and POLM 8 g/kg (T₇) had significantly higher (P < 0.05) BWG with superior (P < 0.05) feed efficiency in the overall growth period. Chickens fed on diets T₃ and T₇ had longer (P < 0.05) villi for duodenum as well as for jejunum. Furthermore, the birds fed on supplementations T₃ and T₇ showed improved (P < 0.05) digestibility of ether extract (EE), and dry matter (DM) compared to the control group. However, least (P < 0.05) crude protein (CP) digestibility was recorded for T_4. In conclusion, dietary supplementations of PBLM 4 g/kg and POLM 8 g/kg were positively modulated the intestinal microarchitecture with enhanced nutrient digestibility, resulted in maximum body weight gain, thus improved the growth performance of broiler chickens.     

Effects of rapeseed meal fiber content on phosphorus and calcium digestibility in growing pigs fed diets without or with microbial phytase

The optimization of dietary phosphorus (P) and calcium (Ca) supply requires a better understanding of the effect of dietary fiber content of co-products on the digestive utilization of minerals. This study was designed to evaluate the effects of dietary fiber content from 00-rapeseed meal (RSM) on P and Ca digestibility throughout the gastrointestinal tract in growing pigs fed diets without or with microbial phytase. In total, 48 castrated male pigs (initial BW=36.1±0.4 kg) were housed in metabolic crates for 29 days. After an 8-day adaptation period, pigs were allocated to one of the eight treatments. The impact of dietary fiber was modulated by adding whole RSM (wRSM), dehulled RSM (dRSM) or dRSM supplemented with 4.5% or 9.0% rapeseed hulls (dRSMh1 and dRSMh2). Diets contained 0 or 500 phytase unit of microbial phytase per kg. From day 14 to day 23, feces and urine were collected separately to determine apparent total tract digestibility (ATTD) and apparent retention (AR) of P and Ca. At the end of the experiment, femurs and digestive contents were sampled. No effect of variables of interest was observed on growth performance. Microbial phytase increased ATTD and AR of P (P<0.001) but the P equivalency with the wRSM diet was lower than expected. Moreover, stomach inorganic P (iP) solubility was improved by microbial phytase (P<0.001). The ATTD of Ca was not affected by microbial phytase which increased AR of Ca and femur characteristics (P<0.05). Ileal recovery of P was not affected by microbial phytase but cecal recovery was considerably reduced by microbial phytase (P<0.001). The decrease in digesta pH between the distal ileum and cecum (7.6 v. 5.9) enhanced the solubility of iP and may have improved its absorption, as supported by the negative relationship between soluble iP and pH (R²=0.40, P<0.001 without microbial phytase and R²=0.24, P=0.026 with microbial phytase). The inclusion of hulls improved the solubility of iP (P<0.05). In conclusion, dehulling does not largely increase nutrient digestibility although dRSM seems to improve the efficacy of microbial phytase in releasing phosphate in the stomach. Moreover, dietary fiber may affect solubilization process in the cecum which potentiates the effect of microbial phytase on P digestibility.     

Estimates of dietary threshold levels for crude protein and amino acids to obtain plateau values of apparent ileal crude protein and amino acid digestibilities in newly weaned pigs

This study was conducted to estimate dietary threshold levels for crude protein (CP) and amino acids (AA) at which apparent ileal digestibilities (AID) of CP and AA in assay diets for newly weaned pigs reach plateaus. A total of 14 (12 + 2 for replacement) three-week old barrows were fitted with simple T cannulas at the distal ileum. Corn starch-based diets containing six graded levels of CP from casein, 90, 155, 220, 285, 350, or 415 g CP/kg assay diet (as-fed), were formulated. At 28 days of age, the pigs were randomly allocated to the six dietary treatments with two pigs per CP level in four weekly repeated measurement periods. They were fed twice daily a total of 30 g (as-fed) per kg of individual body weight at 8:00 and 20:00 h. The dietary CP and AA levels affected AID of CP and most AA (p = 0.005 to p = 0.040) in the assay diets. The AID of CP and AA were higher at 155 and 220 compared to 90 g CP/kg assay diet (p < 0.001 to p = 0.047). Initially, the AID of CP and AA increased sharply then gradually reached, at individual break points (p < 0.001 to p = 0.047), their plateaus (p < 0.001), which did not change up to dietary CP levels of 415 g/kg assay diet and the AID values became independent of the dietary AA levels. The piglets' capacity to digest CP and absorb AA was not limiting under these experimental conditions. There was no effect of age on AID of CP and AA (p = 0.056 to p = 0.899) except for a linear increase (p = 0.045) in AID of glycine from Period 1 to 4. Segmented quadratic with plateau relationships between the AID of CP and AA and their dietary contents were fitted for CP and each AA. The lower end points of 95% confidence intervals of the plateau AID values were defined to represent the initial plateau AID. The dietary CP and AA contents, corresponding to the initial plateau AID values, represent the dietary threshold levels. For CP and the indispensable amino acids, the plateau AID [%] and the dietary threshold levels [g/kg DM], respectively, in casein were: CP, 94.2 and 176; arginine, 95.1 and 7; histidine, 96.0 and 5; isoleucine, 96.4 and 8; leucine, 96.8 and 16; lysine, 96.8 and 12; methionine, 97.9 and 5; phenylalanine, 96.2 and 10; threonine, 93.4 and 9; tryptophan, 94.3 and 2; valine, 95.9 and 11. For the determination of plateau AID in piglets, the crude protein and amino acid contents in the assay diets should meet or exceed the corresponding dietary threshold levels.     

Dietary supplementation with arginine and glutamic acid alters the expression of amino acid transporters in skeletal muscle of growing pigs

Amino Acids - Sixty Duroc × Large White × Landrace pigs with an average initial body weight (BW) of 77.1 ± 1.3&nbsp;kg were selected to...     

Impact of wheat grinding and pelleting in a wheat–rapeseed meal diet on amino acid ileal digestibility and endogenous losses in pigs

The purpose of the current experiment was to investigate the impacts of grinding and pelleting procedures applied to wheat in a wheat–rapeseed meal diet on the coefficients of standardized ileal digestibility, i.e., apparent digestibility corrected for basal endogenous losses (CSID), and true ileal digestibility, i.e., apparent digestibility corrected for total endogenous losses (CTID), of nitrogen (N) and amino acids (AA) in pigs. Ileal digestibility was measured by collecting digesta from pigs fitted with ileorectal anastomoses. Four diets, involving four technological treatments applied to wheat, were compared in vivo according to a 4 × 4 Latin square design (four pigs each fed four diets during four successive periods of 1 week). The technological treatments of wheat were two grinding procedures and two pelleting processes. Wheat was ground to obtain mean flour particle sizes of 1000 and 500 μm, leading after mixing with rapeseed meal and minerals-vitamins premix to the first and second diets named “coarse” and “fine”, respectively. Part of the 500 μm wheat flour was pelleted through dies of same screen diameter (4 mm) but different thicknesses, 16 and 20 mm, inducing a low and high compression ratio, leading after mixing with rapeseed meal and premix to the third and fourth diets named “LCR” and “HCR”, respectively. Basal endogenous losses were determined by feeding a protein-free diet during the 5th week of the experiment. Total endogenous losses were measured by way of the isotopic dilution method using ¹⁵N-labeled wheat and rapeseed meal. Decreasing wheat particle size from 1000 to 500 μm improved (P<0.05) the coefficient of ileal digestibility of dietary energy (0.707 versus 0.665), organic matter (0.718 versus 0.677) and dry matter (0.681 versus 0.645), but neither AA CSID nor N retention. The pelleting processes did not further increase (P>0.10) energy or organic matter digestibility but improved (P<0.05) N and AA CSID (0.785 versus 0.759 for N and 0.725 versus 0.679 for lysine, with HCR versus fine diet, respectively). Pelleting wheat flour at higher compression ratio (HCR versus LCR diet) was more efficient to improve dietary N and AA digestibility values due to a significant decrease in ileal specific, i.e., total minus basal, N and AA endogenous losses (P<0.05) associated with an increase in CTID. It is concluded that pelleting wheat fine flour at high compression ratio allows maximizing AA digestibility and availability of a wheat–rapeseed meal diet.     

Interaction of CP levels in maternal and nursery diets,and its effect on performance,protein digestibility,and serum urea levels in piglets

Reduced protein levels in nursery diets have been associated with a lower risk of postweaning diarrhea, but the interaction with CP levels in maternal diet on the performance of the offspring remains unclear. The objective of this study was to determine the effect of protein content in sow gestation and piglet nursery diets on the performance of the piglets until slaughter. This was studied in a 2 × 2 factorial trial (35 sows, 209 piglets), with higher or lower (H or L) dietary CP in sow diets (168 vs 122 g CP/kg) during late gestation. A standard lactation feed was provided for all sows (160 g CP/kg). For both sow treatments, half of the litters received a higher or lower CP in the piglet nursery diet (210 vs 166 g CP/kg). This resulted in four possible treatment combinations: HH, HL, LH and LL, with sow treatment as first and piglet treatment as second letter. For each phase, all diets were iso-energetic and had a similar level of essential amino acids. P_s*p is the p-value for the interaction effect between sow and piglet treatment. In the nursery phase (3.5–9 weeks of age), a tendency toward interaction between piglet and sow treatments with feed efficiency (P_s*p = 0.08) was observed with HH having the highest gain:feed ratio (G:F) (0.74 ± 0.01), LH the lowest (0.70 ± 0.01) and the other two groups intermediate. In the growing-finishing phase, an interaction was observed between the piglet and sow diets with decreased G:F for LH (P_s*p = 0.04) and a tendency toward interaction with increased daily feed intake for LH (P_s*p = 0.07). The sow diet showed a tendency toward a long-lasting effect on the dressing percentage and meat thickness of the offspring, which was higher for the progeny of H sows (P_s < 0.01 and P_s = 0.02, respectively). At 23 weeks, serum urea concentrations tended to be lower for the HH and LL groups (P_s*p = 0.07). Fecal consistency scores were higher at day 10–day 14 after weaning for piglets from L sows (P_s = 0.03 and P_s < 0.01, respectively). At day 7 after weaning, fecal consistency score was higher for piglets fed the higher protein diet (P_p < 0.01). At 8 weeks of age, the apparent total tract digestibility of CP (ATTD_CP) interacted between piglet and sow diet (P_s*p = 0.02), with HH showing the highest digestibility values. In conclusion, the protein levels in sow late-gestation and piglet nursery diets interacted with feed efficiency, ATTD_CP and serum urea concentrations in the nursery phase.     

Determination of energy and amino acid digestibility in growing pigs fed corn distillers' dried grains with solubles containing different lipid levels

Two experiments were conducted to estimate the digestibility of energy, nitrogen and amino acids (AA) in growing pigs fed diets containing one of five corn distillers' dried grains with solubles (DDGS), including three normal oil DDGS (NO-DDGS) and two low oil DDGS (LO-DDGS) samples. Exp. 1 was conducted to determine the digestible energy (DE) and metabolisable energy (ME) content. Six growing barrows (initial body weight [BW]: 35.1 +/- 2.2 kg) were allotted to a 6 x 6 Latin square design, with six periods and six diets. One diet was a corn soybean meal basal diet and the other five diets were based on corn, soybean meal and 28.8% DDGS. The average DE and ME values for the three NO-DDGS samples were 16.0 and 14.9 MJ/kg dry matter (DM). These values were 9 and 13% greater than the LO-DDGS values of 14.7 and 13.2 MJ/kg DM respectively. Exp. 2 was conducted to determine and compare apparent (AID) and standardised (SID) ileal digestibility for crude protein and AA in the five DDGS samples. Six growing barrows (initial BW, 32.2 +/- 1.9 kg) fitted with a simple T-cannula were allotted to a 6 x 6 Latin square design with six periods and six diets. Five of the diets were based on the five DDGS samples, and the remaining one diet was nitrogen-free diet based on cornstarch and sucrose. Titanium dioxide (0.1%) was used as inert marker. The results of the experiment showed the largest variation among the different samples in AID and SID for lysine (from 41.8 to 65.8% and 53.8 to 73.9% respectively) and threonine (from 54.3 to 73.8% and 65.2 to 79.5% respectively). Also, among the indispensable AA, the SID values for arginine, histidine, threonine and tryptophan observed in LO-DDGS were not different from the values derived from NO-DDGS. In conclusion, LO-DDGS may have decreased energy compared with NO-DDGS because of its lower fat content. However, oil removal during the production of DDGS may not affect amino acid digestibility.     

Effects of amino acid supplementation on the nutritive quality of fermented linseed meal protein in the diets for rohu, Labeo rohita, fingerlings

A feeding trial was conducted for 8 weeks to examine the effects of partial substitution of fish meal (FM) protein (crude protein content: 58.5%) with linseed meal protein with and without supplemental amino acids in diets for rohu Labeo rohita (Hamilton), fingerlings (mean weight: 1.50 ± 0.3 g). Prior to incorporation into the diets, linseed meal was fermented with lactic acid bacteria ( Lactobacillus acidophilus ) to reduce/eliminate the antinutritional tannin and phytic acid factors. Twelve experimental diets (diets D1–D12) were formulated to replace the FM protein from a reference diet (RD) with linseed meal protein at different levels (four sets of diets, of which each set of three diets contained 25%, 50% and 75% replacement of FM protein by linseed meal protein, respectively). Diets D1–D3 were not supplemented with any amino acid. Lysine was supplemented in diets D4–D6. Diets D7–D9 were supplemented with methionine + cystine (together), and diets D10–D12 contained lysine and methionine + cystine (together). Lysine and methionine + cystine (together) were added to the diets at 5.7% and 3.1% of dietary protein, respectively. The groups of fish fed diets without amino acid supplementation had significantly lower percentages of weight gain, specific growth rate and high feed : gain ratio than the fish groups fed other experimental diets. The addition of lysine and methionine + cystine to the diet in which 50% of the FM protein was replaced by linseed meal protein (diet D11) significantly improved fish performance. The results of the present study suggest that rohu fingerlings can effectively utilize the supplemented amino acids and that linseed meal protein can replace up to 50% of the FM protein in rohu diets if the linseed meal is properly processed (fermented) and supplemented with the lacking amino acids.     

Effects of balancing crystalline amino acids in diets containing heat-damaged soybean meal or distillers dried grains with solubles fed to weanling pigs

Two experiments were conducted to investigate if adjustments in diet formulations either based on total analysed amino acids or standardized ileal digestible (SID) amino acids may be used to eliminate negative effects of including heat-damaged soybean meal (SBM) or heat-damaged corn distillers dried grains with solubles (DDGS) in diets fed to weanling pigs. In Experiment 1, four corn–SBM diets were formulated. Diet 1 contained non-autoclaved SBM (315 g/kg), and this diet was formulated on the basis of analysed amino acid concentrations and using SID values from the AminoDat® 4.0 database. Diet 2 was similar to Diet 1 in terms of ingredient composition, except that the non-autoclaved SBM was replaced by autoclaved SBM at 1 : 1 (weight basis). Diet 3 was formulated using autoclaved SBM and amino acid inclusions in the diet were adjusted on the basis of analysed total amino acid concentrations in the autoclaved SBM and published SID values for non-autoclaved SBM (AminoDat® 4.0). Diet 4 also contained autoclaved SBM, but the formulation of this diet was adjusted on the basis of analysed amino acids in the autoclaved SBM and SID values that were adjusted according to the degree of heat damage in this source of SBM. Pigs (160; initial BW: 10.4 kg) were allotted to the four treatments with eight replicate pens per treatment in a randomized complete block design. Diets were fed to pigs for 21 days. The gain to feed ratio (G : F) was greater (P<0.05) for pigs fed Diet 1 compared with pigs fed the other diets and pigs fed Diet 4 had greater (P<0.05) G : F than pigs fed Diet 2. In Experiment 2, 144 pigs (initial BW: 9.9 kg) were allotted to four diets with eight replicate pens per diet. The four diets contained corn, SBM (85 g/kg) and DDGS (220 g/kg), and were formulated using the concepts described for Experiment 1, except that heat-damaged DDGS, but not heat-damaged SBM, was used in the diets. Pigs fed Diet 1 had greater (P<0.05) G : F than pigs fed Diet 2, but no differences were observed for G : F among pigs fed diets containing autoclaved DDGS. Results demonstrate that the negative effects of heat damage of SBM or DDGS may be ameliorated if the reduced concentration and digestibility of amino acids in heat-damaged SBM or DDGS is taken into account in diet formulation. Further research is needed to improve the prediction of the ileal digestibility of amino acids in heat-processed ingredients used in practical diet formulations.