Apparent Ileal Digestibility Coefficients Research Articles

Influence of feed form and particle size on performance, nutrient utilisation, and gastrointestinal tract development and morphometry in broiler starters fed maize-based diets

The influence of feed form and particle size on the performance, coefficient of apparent ileal digestibility (CAID) of nutrients, apparent metabolisable energy (AME) and intestinal morphology in broiler starters fed maize-based diets was examined in this study. Two feed forms (mash and pellet) and three particle sizes (fine, medium and coarse) were evaluated in a 2×3 factorial arrangement of treatments. Birds fed pelleted diets had higher (P<0.05) weight gain and feed intake than those fed mash diets. In mash diets, fine grinding resulted in lower (P<0.05) feed per unit gain compared to medium and coarse grinding, whereas, in pelleted diets, there was no effect (P>0.05) of particle size. Gizzard pH was not influenced (P>0.05) by particle size in mash diets, but fine grinding increased (P<0.05) gizzard pH compared to medium and coarse grinding in pelleted diets. Pelleting reduced (P<0.05) the CAID of nitrogen but increased (P<0.05) the ileal fat digestibility. Particle size had no effect (P>0.05) on CAID of starch and AME in mash diets, but in pelleted diets, pellets made from medium and coarsely ground maize showed higher (P<0.05) starch digestibility. Coarse grinding resulted in higher (P<0.05) AME in pelleted diets. Feeding pelleted diets reduced (P<0.05) the CAID of calcium and phosphorus, but increased (P<0.05) that of sodium. Medium and coarse grindings resulted in higher (P<0.05) calcium digestibility than fine grinding. Feeding pelleted diets reduced (P<0.05 to 0.001) the relative length of all small intestinal segments and the relative weight of pancreas, proventriculus, and gizzard. Medium and coarse grinding increased (P<0.05) the gizzard weight compared to fine grinding. In both the duodenum and jejunum, birds fed pelleted diets had greater (P<0.05) villus height than those fed mash diets. Goblet cell number in duodenum was higher (P<0.05) in birds fed diets containing fine particles compared to those fed medium and coarse particle sizes. The crypt depth in jejunum was greater (P<0.05) in birds fed pelleted diets. Overall, the present data showed that coarse grinding of maize, through enhanced gizzard development and functionality, is beneficial to nutrient and energy utilisation and growth performance in broilers fed pelleted diets.

Use of larvae meal as protein source in broiler diet: Effect on growth performance, nutrient digestibility, and carcass and meat traits.

The aim of this research was to study the effect of insect meal from larvae ( larvae meal [TML]) as complete replacement of soybean meal (SBM) on growth performance, nutrient digestibility, and carcass and meat traits of broilers. A total of eighty 30-d-old male Shaver brown broilers were homogenously divided into 2 groups (each consisting of 8 replicates of 5 birds). Up to 62 d of age, the groups were fed 2 isoproteic and isoenergetic diets differing for the ingredient used as the main protein source: the control group was fed a corn-SBM-based diet, whereas in the TML group, the SBM was completely replaced by TML. Broiler growth performance was measured during the trial. At 62 d of age, 2 broilers per replicate (16 per group) were slaughtered and apparent ileal digestibility coefficients and carcass and meat traits were determined. The use of TML as the main protein source in the broiler diet had no significant effect on most growth performance and carcass traits and chemical and physical properties of meat, the latter being important for marketing purposes. The feed conversion ratio in the entire experimental period (from 30 to 62 d) was improved in the TML group compared with the SBM group ( < 0.05). The apparent ileal digestibility coefficients of DM, OM, and CP in broilers fed the SBM diet were greater ( < 0.01) than the other group. The full digestive system in broilers fed SBM had a lower ( < 0.05) absolute and relative weight than that of broilers fed TML. Also, the weight and the percentage of the spleen in the SBM group were lower ( < 0.05) than those in the TML group. The length of the entire intestine in the group fed TML was greater ( < 0.05) than the other group and the same happened when intestinal length was expressed as percentage of broiler BW ( < 0.05). Among the different intestinal tracts, the ileum and ceca of broilers fed TML had a greater ( < 0.05) length than that of broilers fed SBM. Also, ceca weight (as an absolute value or percentage on live weight) in broilers fed TML was greater ( < 0.05) than that of broilers fed SBM. Breast pH and cooking losses in broilers fed TML were greater ( < 0.05) than those of broilers fed SBM. Chemical characteristic of meat obtained from right breast of slaughtered broilers were unaffected by dietary treatments. larvae meal can be a suitable alternative protein source for growing broilers and also when used as principal protein contributor to the diet.

Apparent ileal digestibility of calcium in limestone for broiler chickens

The objective of the study that is presented herein was to determine the apparent ileal calcium (Ca) digestibility of limestone for broiler chickens as influenced by limestone source and dietary phosphorus (P) concentration. Limestone from three commercial sources (coded as LM-1, LM-2 and LM-3) were obtained, ground to pass through a 0.2mm sieve and analysed for mineral composition and in vitro solubility. Analysed Ca concentration and in vitro solubility coefficient of LM-1, LM-2 and LM-3 were 410, 390 and 420g/kg, and 0.28, 0.29 and 0.27, respectively. Two experimental diets, containing 9g/kg Ca, were developed from each limestone source with 0 and 4.5g/kg dietary P. Titanium dioxide was incorporated as an indigestible marker. Each experimental diet was then randomly allotted to six replicate cages (eight birds per cage) and fed from day 21 to 24 post-hatch. Apparent ileal digestibility of Ca was calculated using the indicator method. Apparent ileal Ca digestibility coefficients of LM-1, LM-2 and LM-3 were determined to be 0.58, 0.61 and 0.54, respectively. Calcium digestibility of LM-3 was lower (P<0.05) than LM-2 but similar (P>0.05) to LM-1. There was no difference (P>0.05) between the Ca digestibility of LM-1 and LM-2. Increasing the dietary P concentration from 0 to 4.5g/kg in assay diets increased (P<0.05) the average Ca digestibility from 0.56 to 0.60.

Pigs that are divergent in feed efficiency, differ in intestinal enzyme and nutrient transporter gene expression, nutrient digestibility and microbial activity

Feed efficiency is an important trait in the future sustainability of pig production, however, the mechanisms involved are not fully elucidated. The objective of this study was to examine nutrient digestibility, organ weights, select bacterial populations, volatile fatty acids (VFA’s), enzyme and intestinal nutrient transporter gene expression in a pig population divergent in feed efficiency. Male pigs (n=75; initial BW 22.4 kg SEM 2.03 kg) were fed a standard finishing diet for 43 days before slaughter to evaluate feed intake and growth for the purpose of calculating residual feed intake (RFI). Phenotypic RFI was calculated as the residuals from a regression model regressing average daily feed intake (ADFI) on average daily gain (ADG) and midtest BW0.60 (MBW). On day 115, 16 pigs (85 kg SEM 2.8 kg), designated as high RFI (HRFI) and low RFI (LRFI) were slaughtered and digesta was collected to calculate the coefficient of apparent ileal digestibility (CAID), total tract nutrient digestibility (CATTD), microbial populations and VFA’s. Intestinal tissue was collected to examine intestinal nutrient transporter and enzyme gene expression. The LRFI pigs had lower ADFI (P<0.001), improved feed conversion ratio (P<0.001) and an improved RFI value relative to HRFI pigs (0.19 v. −0.14 SEM 0.08; P<0.001). The LRFI pigs had an increased CAID of gross energy (GE), and an improved CATTD of GE, nitrogen and dry matter compared to HRFI pigs (P<0.05). The LRFI pigs had higher relative gene expression levels of fatty acid binding transporter 2 (FABP2) (P<0.01), the sodium/glucose co-transporter 1 (SGLT1) (P<0.05), the glucose transporter GLUT2 (P<0.10), and the enzyme sucrase–isomaltase (SI) (P<0.05) in the jejunum. The LRFI pigs had increased populations of lactobacillus spp. in the caecum compared with HRFI pigs. In colonic digesta HRFI pigs had increased acetic acid concentrations (P<0.05). Differences in nutrient digestibility, intestinal microbial populations and gene expression levels of intestinal nutrient transporters could contribute to the biological processes responsible for feed efficiency in pigs.

Determination of Ileal Amino Acid Digestibilities of Some By-products for Chickens

The aim of this study was to determine the standardized ileal digestibility of amino acids in six by-product ingredients for broiler, i.e., copra meal, rapeseed meal, feather meal, hydrolyzed poultry meal, meat and bone meal, and shrimp head meal. Luong Phuong chickens at 35 days of age were used in the trials. Dietary protein in all assay diets was supplied solely by the test ingredient. In the case of protein-rich ingredients, dextrose was added to assay diets to obtain 20% of crude protein. Standardized ileal amino acid digestibilities were calculated by correcting the apparent ileal digestibility coefficients by basal endogenous amino acid losses. Results of study showed that the variation in ileal digestibility coefficients of amino acids was low in rapeseed meal and high in copra meal. Among animal protein meals, the lowest variation of digestibility among amino acids was observed in shrimp head meal. The high standardized ileal digestibilities of Arg, His, Leu + Ile, Thr, Trp, Val, and Phe were observed in hydrolyzed poultry meal and shrimp head meal. Meanwhile, the standardized ileal digestibility values of Lys, Thr, and Trp in feather meal were very low. Meat and bone meal and feather meal was the two least digestible amino acid ingredients.

Nutrient digestibility, digesta volatile fatty acids, and intestinal bacterial profile in growing pigs fed a distillers dried grains with solubles containing diet supplemented with a multi-enzyme cocktail

ABSTRACT This study investigated the effects of adding a multi-enzyme cocktail (MC) to a distillers dried grains with solubles (DDGS)-containing diet on energy and nutrient coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility, digesta volatile fatty acids (VFA) concentration, and gut bacterial profile using ileal-cannulated barrows (n = 9; 62.7 ± 6.4 Kg initial body weight). Three isocaloric/isonitrogenous diets based on corn and soybean meal with 0 (control) or 30% DDGS (DDGS diet) and DDGS diet supplemented with MC (DDGS + MC) were used. The 3 diets were fed to pigs in a 2-period change over design to obtain 6 observations per diet. A casein–cornstarch-based diet was used in a separate period to determine basal endogenous N and AA losses to estimate standardized ileal digestibility (SID) of AA. All diets contained titanium dioxide as a digestibility marker. Ileal digesta and feces were used for VFA and bacterial profile determination, respectively. The CAID for DM, N, starch, and energy were greater (P 0.10). The DDGS diet also decreased (P 0.10) for N and NDF. However, diet had no effect (P > 0.10) on hindgut nutrient disappearance. Diet did not influence (P > 0.10) digesta pH and VFA concentrations except for isovalerate concentration, which was greatest (P 0.10) by diet. In conclusion, adding MC to the DDGS diet improved the digestibility of DM, starch, most AA, but not NDF and N digestibility. The results show that addition of MC to the DDGS diet stimulated the growth of intestinal bacteria with xylanolytic and cellulolytic activities.

Apparent ileal digestibility of protein and amino acids in protein feedstuffs and trypsin activity in the small intestine in broiler chickens

Coefficients of ileal apparent digestibility (CIAD) for crude protein (CP) and amino acids in five protein feedstuffs: corn distillers dried grains with solubles (DDGS), raw full-fat soybean (RFFSB), extruded full fat soybean (EFFSB), soybean meal (SBM), and rapeseed meal (RSM) were determined using 5-week-old male broiler chickens. Trypsin activity in digesta in the ileum and jejunum were also measured. CIAD of CP was the highest in SBM (0.73). The lowest (P &amp;lt; 0.05) CIAD of CP was determined for RFFSB (0.45). There was no significant difference in CIAD of CP between RSM (0.61) and DDGS (0.62). The CIAD values for all essential amino acids except Lys (0.52) were the lowest in RFFSB (P &amp;lt; 0.05). The CIAD of Lys was the lowest in DDGS (0.39, P &amp;lt; 0.05). The CIAD for all essential amino acids was the highest in SBM (P &amp;lt; 0.05). There was no significant difference between EFFSB and SBM (P &amp;gt; 0.05) in CIAD of Leu (0.71, 0.73), His (0.66, 0.69), Lys (0.70, 0.77), Met (0.74, 0.80), Thr (0.60, 0.62), and Val (0.65, 0.67). Both the feedstuff and the intestinal region and their interaction had a significant (P &amp;lt; 0.01) effect on trypsin activity. The CIAD of CP and amino acids were very high and comparable both in EFFSB and SBM. The CIAD values for CP and amino acids in DDGS and RSM were lower than in SBM, but they seemed to be comparable to each other.

Comparative efficacy of xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran- or corn and corn DDGS-based diets supplemented with phytase

Two experiments were conducted to determine the effects of supplemental xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five xylanases from different microbial origins. The xylanases were identified as A, B, C, D and E and fed at 75mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0±0.2kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P<0.05) such that pigs fed wheat diets with xylanases A and C and corn diets with xylanases A and D had greater (P=0.044) ADG than pigs fed xylanase-free diets or wheat diets with xylanase D or corn diets with xylanases B and C. A main effect of xylanase was observed for G:F in which case xylanase A improved G:F by 10% (P=0.010) compared to the control. In Experiment 2, TiO2 (3g/kg) was added in all diets and pigs were allotted diets in a Youden Square design, to give 6 replicates per diet. Interaction (P<0.05) between diet type and xylanase were observed on CAID of gross energy (GE), insoluble arabinose and xylose (iAX), total arabinose and xylose (tAX), insoluble NSP (iNSP), and total NSP (tNSP). In this context, pigs fed wheat-based diets with xylanase C and D and those fed corn-based diets with xylanases B and E had greater (P<0.05) CAID of GE compared to those fed xylanase-free diets. The CAID of tAX and tNSP in pigs fed wheat-based diets with xylanase C and corn-based diets with xylanases B and E were higher (P<0.001) than in pigs fed the other diets. There was no treatment effects on CATTD of GE, DM and crude protein, however, xylanases independently improved (P=0.040) CATTD of fat compared to the control. Different xylanases responded differently in improving dietary components digestibility and growth performance depending on the diet type. However, the comparisons made in the present study are only valid for the test conditions as some of the xylanases may have been dosed at levels below the biological optimum and others well above.

Nutritional value of two insect larval meals (Tenebrio molitor and Hermetia illucens) for broiler chickens: Apparent nutrient digestibility, apparent ileal amino acid digestibility and apparent metabolizable energy

The aim of this study was to determine the apparent digestibility coefficients of the total tract (CTTAD) of nutrients and the apparent metabolizable energy (AME and AMEn) of two insect larval meals (Tenebrio molitor and Hermetia illucens) for broiler chickens. The amino acid (AA) apparent ileal digestibility coefficients (AIDC) was also determined. The experimental diets were: a basal diet and two diets prepared by substituting 250g/kg (w/w) of the basal diet with Tenebrio molitor meal (TM) or Hermetia illucens meal (HI). No statistical difference was found between the two insect larval meals for the CTTAD of the nutrients, except for the CTTAD for ether extract (P<0.001) where the HI meal proved to be more digestible than the TM meal (0.99 and 0.88, respectively). The CTTAD for DM was 0.60 and 0.53; 0.66 and 0.66 for OM; 0.60 and 0.51 for CP, whereas it was 0.64 and 0.69 for GE, for TM and HI, respectively. No difference was observed between TM and HI (P>0.05) for AME or AMEn (AME=16.86 and 17.38MJ/kg DM, respectively; AMEn=16.02 and 16.60MJ/kg DM, respectively). The average AIDC of the 17 analyzed AAs was higher (P<0.001) in TM than in HI (0.86 and 0.68, respectively) because the AIDC of isoluecine, lysine, methionine, phenylalanine, valine, alanine, aspartic acid, glycine, glutamic acid and tyrosine was higher (P<0.05) in TM than in HI. Overall, the present results have shown that TM and HI meals are excellent sources of AME for broilers and a valuable source of digestible AA, particularly as far as TM meal is concerned.

Measurement of true ileal phosphorus digestibility in meat and bone meal for broiler chickens

An experiment was conducted to estimate true ileal phosphorus (P) digestibility of 3 meat and bone meal samples (MBM-1, MBM-2, and MBM-3) for broiler chickens. Four semipurified diets were formulated from each sample to contain graded concentrations of P. The experiment was conducted as a completely randomized design with 6 replicates (6 birds per replicate) per dietary treatment. A total of 432 Ross 308 broilers were assigned at 21 d of age to the 12 test diets. The apparent ileal digestibility coefficient of P was determined by the indicator method, and the linear regression method was used to determine the true P digestibility coefficient. The apparent ileal digestibility coefficient of P in birds fed diets containing MBM-1 and MBM-2 was unaffected by increasing dietary concentrations of P (P > 0.05). The apparent ileal digestibility coefficient of P in birds fed the MBM-3 diets decreased with increasing P concentrations (linear, P < 0.001; quadratic, P < 0. 01). In birds fed the MBM-1 and MBM-2 diets, ileal endogenous P losses were estimated to be 0.049 and 0.142 g/kg DM intake (DMI), respectively. In birds fed the MBM-3 diets, endogenous P loss was estimated to be negative (−0.370 g/kg DMI). True ileal P digestibility of MBM-1, MBM-2, and MBM-3 was determined to be 0.693, 0.608, and 0.420, respectively. True ileal P digestibility coefficients determined for MBM-1 and MBM-2 were similar (P < 0.05), but were higher (P < 0.05) than that for MBM-3. Total P and true digestible P contents of MBM-1, MBM-2, and MBM-3 were determined to be 37.5 and 26.0; 60.2 and 36.6; and 59.8 and 25.1 g/kg, respectively, on an as-fed basis.

Amino acid digestibility in rice co-products fed to growing pigs

The global production of paddy rice exceeds 700 million tons per year. The primary objective of rice production is to produce polished white rice for human consumption, but in this process, several co-products that may be fed to livestock are also generated. The objective of this experiment was to determine the coefficient of ileal apparent digestibility (CIAD) and the coefficient of ileal standardized digestibility (CISD) of crude protein (CP) and amino acids (AA) in 2 sources of full fat rice bran (FFRB), 1 source of defatted rice bran (DFRB), and in broken rice when fed to growing pigs. Seven finishing pigs with an average initial body weight of 70.1 ± 6.3 kg were used. Pigs were surgically fitted with a T-cannula in the distal ileum. Animals were allotted to a 7 × 7 Latin square design with 7 diets and 7 periods. Seven diets were prepared, but 1 diet was unrelated to this experiment; therefore only 6 diets were used in this experiment. One diet was based on bakery meal, and 1 diet was based on broken rice. Three additional diets were formulated by mixing bakery meal and each of the 2 sources of FFRB (FFRB-1 and FFRB-2) or DFRB. The last diet was an N-free that was used to estimate the basal ileal endogenous losses of CP and AA. The CIAD of CP and AA in bakery meal and broken rice was calculated using the direct procedure, but the CIAD of CP and AA in both sources of FFRB and in DFRB was calculated using the difference procedure. The CIAD and CISD of CP and AA in broken rice were greater (P < 0.05) than the CIAD and CISD of CP and AA in all other ingredients. The CIAD of the average of indispensable AA was greater (P < 0.05) for broken rice and less (P < 0.05) for DFRB, than for the 2 sources of FFRB. The CISD for the average of indispensable AA in broken rice (0.949) was greater than in FFRB-1 (0.862), FFRB-2 (0.850), and DFRB (0.817), but there were no differences between the 2 sources of FFRB, and the average CISD of indispensable AA in DFRB was less (P < 0.05) than in the other ingredients. The concentrations of CISD CP and indispensable AA in DFRB were greater (P < 0.05) than in all other ingredients. In conclusion, the CIAD and CISD of CP and AA in broken rice was greater than in FFRB and DFRB, but the greater concentration of CP and AA in FFRB and DFRB result in greater concentrations of CISD CP and AA in FFRB and DFRB than in broken rice.

Measurement of true ileal calcium digestibility in meat and bone meal for broiler chickens

The objective of the present experiment was to determine the true ileal calcium (Ca) digestibility in three samples of meat and bone meal (coded as MBM-1, MBM-2 and MBM-3) for broiler chickens. Four experimental diets, containing graded concentrations of Ca, were formulated from each MBM sample with inclusion levels of 20, 40, 60 and 80g/kg diet. Each experimental diet was randomly allotted to four replicate cages (six birds per cage) and fed for three days from day 28 post-hatch. Apparent ileal digestibility coefficient of Ca was measured by the indicator method and linear regression analysis was used to determine the true Ca digestibility coefficient. Apparent Ca digestibility was unaffected (P>0.05) by increasing Ca concentrations. The apparent digestibility coefficients in MBM-1, MBM-2 and MBM-3 were 0.50, 0.44 and 0.45, respectively. Significant linear (P<0.001) relationship was observed between dietary Ca intake and digesta Ca output for MBM-1, MBM-2 and MBM-3 with R2 values of 0.82, 0.93 and 0.95, respectively. The true ileal digestibility coefficients of Ca in MBM-1, MBM-2 and MBM-3 were determined to be 0.60, 0.46 and 0.50, respectively. The corresponding ileal endogenous Ca losses were 292, 123 and 174mg/kg dry matter intake, respectively.

Measurement of true ileal phosphorus digestibility in maize and soybean meal for broiler chickens: Comparison of two methodologies

An experiment was conducted to determine the true ileal P digestibility of maize and soybean meal for broiler chickens using two methodologies based on the regression method. The two methods differed in dietary protein content and dietary Ca:P ratios in the assay diets used. In Method 1, the test ingredient was used as the sole dietary source of protein and P and a dietary Ca:non-phytate P ratio of around 2:1 was maintained by the addition of limestone. In Method 2, dried egg albumen was used as the additional protein supplement and a dietary Ca:total P ratio of 1.3:1 was maintained by the addition of limestone. For the maize-based diets, disodium phosphate was used as an additional P supplement. Two sets of sequential semi-purified diets containing 200, 460 and 720g/kg of maize or 400, 510 and 620g/kg of soybean meal were formulated. Each set was evaluated as a 2×3 factorial arrangement of treatments, which included two methods and three inclusion levels. The experiment was conducted as a randomised complete block design and a total of 288 of 21-day old male broilers (Ross 308) were assigned to four blocks based on body weights. Each block had 12 cages (six birds per cage) and the 12 test diets were assigned to a cage within each block. Apparent ileal digestibility coefficient of P was determined by the indicator method and linear regression was used to determine true ileal P digestibility. In both methods, ileal P output and ileal digestible P increased linearly with increasing inclusion levels of maize (P<0.01) and soybean meal (P<0.001). Apparent ileal P digestibility coefficients of P determined for maize were higher (P<0.001) in Method 2 compared with Method 1 whereas the opposite trend was observed for soybean meal. True ileal P digestibility coefficients determined for maize in Methods 1 and 2 were 0.728 and 0.426, respectively, and were different (P<0.01). True ileal P digestibility coefficients determined for soybean meal in Methods 1 and 2 were 0.740 and 0.523, respectively, and were different (P<0.01). The present findings showed that estimation of true ileal P digestibility in maize and soybean meal was influenced by the assay methodology employed.

Influence of separate feeding of calcium on nutrient digestibility, energy utilisation and performance of young broilers fed pelleted wheat-based diets

Six broiler starter diets, based on wheat and soybean meal, were formulated to contain 1.1 2.0, 4.0, 6.0, 8.0 and 10.0g calcium (Ca)/kg. All diets were equivalent in respect of total and non-phytate phosphorus contents (5.4 and 3.0g/kg, respectively). The influence of dietary treatments on the growth performance, coefficient of apparent ileal digestibility (CAID) of nitrogen (N), starch, fat and phosphorus (P), Ca retention and apparent metabolisable energy (AME) in broiler starters was evaluated. A total of 288, one-day-old male broilers (Ross 308) were allocated to 36 cages (8birds/cage), and cages were randomly assigned to 6 dietary treatments. Birds were also provided with a source of Ca in a separate feed trough. Birds fed the diet with 1.1g Ca/kg gained more (P<0.05) weight and tended (P=0.08) to have higher feed intake than those fed the diets with 8.0 and 10.0g Ca/kg. Increasing dietary Ca concentrations from 1.1 to 8.0g/kg increased (P<0.05) feed per unit gain, but diets with 1.1 and 10.0g/kg Ca resulted in similar (P>0.05) feed per unit gain. During d 8 to 14, d 15 to 21, and over the entire trial period of 21 d, birds fed Ca-deficient (6.0g Ca/kg and less) diets consumed more (P<0.001) of the separate Ca source. During the third week and over the 21 d trial period, total Ca intake (Ca from feed plus Ca from separate source) of birds fed Ca-insufficient diets was higher (P<0.05) than those fed diets with higher dietary Ca concentrations. Diets with 1.1g Ca/kg resulted in the highest (P<0.05) CAID of P. There was no effect (P>0.05) of dietary Ca on the retention of Ca and ash, AME and toe ash. The present data suggest that feeding broilers low Ca diets with access to a separate Ca source, is advantageous in terms of broiler performance, while maintaining bone mineralisation. The data also demonstrate that the provision of separate Ca source may hold promise for reducing the dietary P contents.

Apparent ileal amino acid digestibility of reduced-oil distillers dried grains with solubles fed to broilers from 23 to 31 days of age

An experiment was conducted using male Ross × Ross 708 broiler chicks to determine the effect of oil extraction from corn distillers dried grains with solubles on apparent ileal amino acid digestibility from 23 to 31 d of age. On an as-fed basis, ether extract concentrations were determined as 5.4% (L-distillers dried grains with solubles), 7.9% (M-distillers dried grains with solubles), and 10.5% (H-distillers dried grains with solubles) for the 3 experimental distillers dried grains with solubles sources. Prior to experimentation, each sample (H-distillers dried grains with solubles (control), M-distillers dried grains with solubles and L-distillers dried grains with solubles) was analyzed on an as-fed basis for crude protein (29.2, 27.6, and 27.9%), starch (4.4, 5.2, and 6.1%), neutral detergent fiber (29.5, 33.2, and 29.9%), and total dietary fiber (31.4, 36.6, and 33.6 %). Four hundred and thirty-two male chicks (12 birds per cage; 0.04 m2 per bird) were randomly assigned to 36 battery grower cages. Broilers were fed one of 3 semi-purified diets, which were comprised of 76% L-distillers dried grains with solubles, M- distillers dried grains with solubles, or H-distillers dried grains with solubles as the sole amino acid source from 23 to 31 d of age. Apparent ileal amino acid digestibility coefficients were negatively affected (P < 0.05) by oil extraction for Met (0.722, 0.788, and 0.791), Lys (0.504, 0.510, and 0.552), Thr (0.563, 0.566, and 0.612), Trp (0.708, 0.733, and 0.767), and Arg (0.762, 0.776, and 0.799) for L-distillers dried grains with solubles, M-distillers dried grains with solubles, and H-distillers dried grains with solubles, respectively. Conversely, no differences in apparent amino acid coefficients were reported for Ile, Leu, and Val. These results indicated that L-distillers dried grains with solubles had lower apparent amino acid digestibility coefficients for Met, Lys, Thr, Trp, and Arg compared with H-distillers dried grains with solubles.

Effects of Feeding Prosopis juliflora Pods with and Without Exogenous Enzyme on Performance, Meat Quality and Health of Broiler Chickens

Two experiments were conducted to evaluate the use of Prosopis juliflora pods as a partial replacement of corn as a source of energy for growing broiler chicken. The main objective of Experiment 1, an ileal digestibility assay, was to assess the nutritional value of Prosopis juliflora pods compared with corn for feeding broiler chicken. The two test ingredients, Prosopis juliflora pods and corn were given alone to determine apparent metabolizable energy (AME) and apparent ileal digestibility of crude fibre. Prosopis juliflora pods had significantly lower AME content (10.64 vs 15.26 MJ/kg) and lower apparent ileal digestibility coefficient for crude fibre (0.24 vs 0.63) than corn (p<0.001). The objective of Experiment 2, a growth study, was to test the effect of exogenous enzymes on the nutritive value of Prosopis juliflora pods. Three Prosopis juliflora pods contents (5, 10 and 15%) with and without enzyme supplementation were evaluated. Daily feed intake, body weight gain and feed conversion ratio were measured. At the end of Experiment 2, 64 birds were randomly selected and slaughtered to evaluate carcase and meat quality characteristics. Substitution of corn by 10 and 15% Prosopis juliflora pods significantly depressed AME (p<0.001). Enzyme supplementation did not improve crude fibre digestibility. The inclusion of Prosopis juliflora pods in the diets, except at 5 % decreased average daily gains, feed intake and feed conversion ratio (p<0.001). Addition of Prosopis juliflora pods caused a significant increase in the weights of total digestive tract, pancreas and caecum (p<0.01). Addition of Prosopis juliflora pods or the exogenous enzyme had no significant effect on carcase or meat quality characteristics, haematology, serum biochemistry and sensory evaluation. This study indicated that Prosopis juliflora pods can be included at levels of 5% in broiler diets without affecting performance.

Effects of Enterococcus faecium DSM 7134 supplementation in different energy and crude protein density diets on ileal amino acid digestibility and intestinal shedding of lactobacilli and Escherichia coli in finishing pigs

This experiment was conducted to determine the efficacy of Enterococcus faecium DSM 7134, in different energy and crude protein density diets on ileal amino acid digestibility and intestinal microbial shedding in finishing pigs. Twelve finishing barrows (initial body weight=75.1±3.44kg) were surgically equipped with a T-cannula in the distal ileum and arranged in a triplicate 4×4 Latin square design with four diets and four periods. Diets were formulated with two levels of nutrient density (high energy: 14.6MJ/kg ME or low energy: 14.2MJ/kg ME) and two levels of probiotic (0 or 1.0×109cfu/kg diet). The coefficient of apparent ileal digestibility (CAID) of crude protein (CP), gross energy (GE), and most of the indispensable amino acids (AA) except for His-Phe and Val were increased (P<0.05) by 5.3%, 6.0%, and 5.2–7.2% in pigs fed the E. faecium compared with non-supplemented groups. The CAID of Cys and Gly was 6.2% and 7.0% greater (P<0.05) in E. faecium groups than non-supplemental groups. Ileal and fecal Lactobacilli counts were increased (P<0.05) by 19.9% and 16.6%, and Escherichia coli counts were decreased (P<0.05) by 8.9% and 9.5% in pigs fed the diets supplemented with probiotic, respectively. The CAID of CP, Lys-Met-Thr-Leu-Ile-Cys-Gly as well as the lactobacilli counts were increased in both E. faecium treatments, but values were increased higher in the high density diet. In conclusion, dietary supplementation with 1.0×109cfu/kg of E. faecium DSM 7134 exerted beneficial effects on the CAID of CP and AA and intestinal lactobacilli shedding, especially was administrated in high energy and crude protein density diets.

Effects of maize source and complex enzymes on performance and nutrient utilization of broilers.

The objective of this study was to investigate the effect of maize source and complex enzymes containing amylase, xylanase and protease on performance and nutrient utilization of broilers. The experiment was a 4×3 factorial design with diets containing four source maize samples (M1, M2, M3, and M4) and without or with two kinds of complex enzyme A (Axtra XAP) and B (Avizyme 1502). Nine hundred and sixty day old Arbor Acres broiler chicks were used in the trial (12 treatments with 8 replicate pens of 10 chicks). Birds fed M1 diet had better body weight gain (BWG) and lower feed/gain ratio compared with those fed M3 diet and M4 diet (p<0.05). Apparent ileal crude protein digestibility coefficient of M2 was higher than that of M3 (p<0.05). Apparent metabolisable energy (AME) and nitrogen corrected AME (AMEn) of M1 were significant higher than those of M4 (p<0.05). Supplementation of the basal diets with enzyme A or B improved the BWG by 8.6% (p<0.05) and 4.1% (p>0.05), respectively. The fresh feces output was significantly decreased by the addition of enzyme B (p<0.05). Maize source affects the nutrients digestibility and performance of broilers, and a combination of amylase, xylanase and protease is effective in improving the growth profiles of broilers fed maize-soybean-rapeseed-cotton mixed diets.

Effects of protease, phytase and a Bacillus sp. direct-fed microbial on nutrient and energy digestibility, ileal brush border digestive enzyme activity and cecal short-chain fatty acid concentration in broiler chickens.

Two experiments were conducted to determine the effects of protease and phytase (PP) and a Bacillus sp. direct-fed microbial (DFM) on dietary energy and nutrient utilization in broiler chickens. In the first experiment, Ross 308 broiler chicks were fed diets supplemented with PP and DFM in a 2×2 factorial arrangement. The 4 diets (control (CON), CON + PP, CON + DFM, and CON + PP + DFM) were fed from 15–21 days of age. In Experiment 1, significant interaction (P≤0.01) between PP and DFM on the apparent ileal digestibility coefficient for starch, crude protein, and amino acid indicated that both additives increased the digestibility. Both additives increased the nitrogen retention coefficient with a significant interaction (P≤0.01). Although no interaction was observed, significant main effects (P≤0.01) for nitrogen-corrected apparent ME (AMEn) for PP or DFM indicated an additive response. In a follow-up experiment, Ross 308 broiler chicks were fed the same experimental diets from 1–21 days of age. Activities of ileal brush border maltase, sucrase, and L-alanine aminopeptidase were increased (P≤0.01) by PP addition, while a trend (P = 0.07) for increased sucrase activity was observed in chickens fed DFM, in Experiment 2. The proportion of cecal butyrate was increased (P≤0.01) by DFM addition. Increased nutrient utilization and nitrogen retention appear to involve separate but complementary mechanisms for PP and DFM, however AMEn responses appear to have separate and additive mechanisms.

Improvements in growth performance, bone mineral status and nutrient digestibility in pigs following the dietary inclusion of phytase are accompanied by modifications in intestinal nutrient transporter gene expression.

Phytase (PHY) improves growth performance, nutrient digestibility and bone structure in pigs; however, little is known about its effects on intestinal nutrient transporter gene expression. In the present study, a 44 d experiment was carried out using forty-eight pigs (11·76 (sem 0·75) kg) assigned to one of three dietary treatment groups to measure growth performance, coefficient of apparent ileal digestibility (CAID), coefficient of apparent total tract nutrient digestibility (CATTD) and intestinal nutrient transporter gene expression. Dietary treatments during the experimental period were as follows: (1) a high-P (HP) diet containing 3·4 g/kg available P and 7·0 g/kg Ca; (2) a low-P (LP) diet containing 1·9 g/kg available P and 5·9 g/kg Ca; (3) a PHY diet containing LP diet ingredients+1000 phytase units (FTU)/kg of PHY. The PHY diet increased the average daily gain (P< 0·05) and final body weight (P< 0·01) and decreased the feed conversion ratio (P< 0·05) compared with the LP diet. Pigs fed the PHY diet had a higher CAID of gross energy compared with those fed the HP and LP diets (P< 0·001). Pigs fed the PHY diet had increased CAID of P (P< 0·01) and CATTD of Ca and P (P< 0·001) compared with those fed the LP diet. The PHY diet increased the gene expression of the peptide transporter 1 (PEPT1/SLC15A1) (P< 0·05) in the ileum compared with the LP diet. The LP diet decreased the gene expression of the sodium-glucose-linked transporter 1 (SGLT1/SLC5A1) and GLUT2/SLC2A2 (P< 0·05) and increased the expression of membrane Ca channel (TRPV6) and calbindin compared with the HP diet (P< 0·001). In conclusion, feeding a diet supplemented with PHY improves growth performance and nutrient digestibility as well as increases the gene expression of the peptide transporter PEPT1.