Wheat-based Diets Research Articles

Effect of different levels of rapeseed meal and sunflower meal and enzyme combination on the performance, digesta viscosity and carcass traits of broiler chickens fed wheat-based diets

The aim of the present experiment was to examine the effect of different levels of rapeseed meal (RSM) and sunflower meal (SFM) and enzyme combination (endoxylanase and β-glucanase) on the production performance, carcass quality, gizzard development and digesta viscosity of broiler chickens. The experimental design was a 3×2 factorial arrangement of treatments evaluating three diet types containing different levels of RSM and SFM (low (L), medium (M) and high (H)) and two levels of enzyme inclusion (0 or 100 g/tonne diet to provide 1220 U xylanase and 152 U β-glucanase per kg diet). Broiler starter and grower/finisher diets were formulated, based on wheat and soya bean meal and containing 50, 50 and 80 g/kg RSM and 0, 50 and 60 g/kg SFM for L, M and H treatments, respectively, during starter period and 80, 80 and 120 g/kg RSM and 0, 80 and 100 g/kg SFM for L, M and H, respectively, during grower/finisher period, and each diet was fed ad libitum to eight pens of 20 male broilers each. During the starter period (1 to 21 days), birds fed the H treatment had lower (P<0.05) BW gain (BWG) compared with those fed the L and M treatments. Diet type also influenced (P<0.05) feed intake (FI). Feeding the H treatment reduced (P<0.05) FI compared with the M treatment. Diet type and enzyme supplementation had no effect (P>0.05) on feed conversion ratio (FCR). During the grower/finisher phase (22 to 42 day) and over the entire period (1 to 42 day) birds fed the H treatment had lower (P<0.05) BWG and higher (P<0.05) FCR compared with those fed the L and M diets. Enzyme supplementation improved (P<0.05) FCR compared with the unsupplemented diets. No interactions (P>0.05) between RSM and SFM inclusion level and enzyme supplementation were observed for any of the measured parameters at any period. Diet type and enzyme supplementation had no effect (P>0.05) on carcass traits, abdominal fat pad, breast meat yield and jejunal digesta viscosity. Diet type influenced (P=0.05) relative empty gizzard weight, where the H treatment had higher relative empty gizzard weight compared with the L treatment. Enzyme supplementation tended (P=0.10) to increase relative empty gizzard weight. The present data suggest that high inclusion of SFM and RSM negatively influenced broiler performance. Enzyme supplementation improved FCR at all levels of RSM and SFM included in this study, but did not recover the reduction in weight gain caused by high inclusion of RSM and SFM.

Growth performance of nursery pigs fed pelleted wheat-based diets containing graded levels of supplemental xylanase

Growth performance of nursery pigs fed pelleted wheat-based diets containing graded levels of supplemental xylanase

Anthocyanin-Rich Diet in Chemically Induced Colitis in Mice

The aetiology of inflammatory bowel diseases is unclear, but oxidative stress plays a key role in the pathogenesis. Anthocyanins – plant polyphenols – were shown to have antioxidant and anti-inflammatory properties. The aim of this study was to investigate the potential protective effects of anthocyanins on the oxidative status in mice with chemically induced colitis. Adult male mice were randomly divided into a control group drinking tap water and a colitis group drinking 1% dextran sulphate sodium solution. Animals had ad libitum access to a control wheat-based diet or food based on wheat producing anthocyanins. Bodyweight and stool consistency were monitored daily for 14 days. At the end of the experiment, colon length was measured and tissue samples were collected for the assessment of histology and oxidative status. Mice with colitis had lower body weight, higher stool score and shorter colon than control mice. Anthocyanins had neither an effect on stool consistency, nor on bodyweight loss and colon length. In the colon, liver and plasma, analysis of oxidative stress markers and antioxidant status revealed no significant differences between the groups. Food made from wheat producing anthocyanins did not protect mice from the consequences of chemically induced colitis. The measured biomarkers do not confirm the role of oxidative stress in this model of colitis. Further optimization of the anthocyanin- rich food might be needed before further experiments are conducted.

A combination of xylanase, amylase and protease influences growth performance, nutrient utilisation, starch and protein digestive dynamics in broiler chickens offered maize-, sorghum- and wheat-based diets

In order to examine the influence of an enzyme combination of xylanase, amylase and protease on growth performance and energy utilisation in boiler chickens offered maize-, sorghum- and wheat-based diets and also determine the impact of exogenous enzymes on digestive dynamics of starch and protein in the small intestine and their relativity to broiler performance, a 3 × 2 factorial array of dietary treatments were offered to 288 male Ross 308 chicks from 7 to 27 days post-hatch. Apparent digestibility coefficients of starch, protein and fat in the proximal jejunum, distal jejunum, proximal ileum and distal ileum were determined at Day 27. The digestion rates of starch, protein and energy were predicted by using exponential mathematical models to fit apparent digestibility coefficients with mean retention times in each small intestinal segment. Sorghum-based diets supported the highest weight gain (P &lt; 0.05) and feed intake (P &lt; 0.05) but feed conversion ratios (FCR) were similar across all three grain-based diets (P &gt; 0.10). There were significant interactions between grain type and enzyme supplementation in FCR and the enzyme combination significantly improved FCR in maize-based diets only (P &lt; 0.01). The enzyme combination significantly increased apparent metabolisable energy (AME) in all three grain-based diets (P &lt; 0.05) and increased nitrogen-corrected apparent metabolisable energy (AMEn) in maize- and wheat-based diets (P &lt; 0.05). Wheat-based diets had the lowest N retention (P &lt; 0.01), relative gizzard weight (P &lt; 0.001) and highest gizzard pH (P &lt; 0.05). There were significant grain × enzyme supplementation interactions for starch (P &lt; 0.01) and N (P &lt; 0.05) digestibility coefficients in the four small intestinal segments. Starch digestibility responses to the enzyme combination were most pronounced in wheat-based diets with significant improvement in all segments. The enzyme combination significantly retarded starch digestion rates (P &lt; 0.05) but did not influence protein (N) digestion rates (P &gt; 0.25). In conclusion, feed conversion of sorghum-based diet (1.475) was significantly more efficient than those based on maize (1.518) and wheat (1.532) in non-supplemented diets. The enzyme combination significantly improved energy utilisation (AME) in all three grain-based diets and improved feed conversion efficiency in maize-based diets.

Effect of incremental levels of crude degummed canola oil on milk progesterone, plasma luteinizing and follicle stimulating hormones of primiparous Holstein–Friesian cows in a pasture-based system

Dietary supplementation of lactating cows with fat can alter the profiles of key reproductive hormones and boost postpartum energy balance. However, published data under Australian pasture-based dairy production conditions are scanty and inconsistent. Therefore, the objective of this study was to determine whether dietary inclusion of crude degummed canola oil (CDCO) at incremental levels for eight-weeks will have significant influence on progesterone (P4), luteinizing hormone (LH) and follicle stimulating hormone (FSH) of primiparous Holstein–Friesian cows grazing pastures. We tested the hypothesis that postpartum supplementation of primiparous Holstein–Friesian cows with dietary CDCO in a pasture-based system will alter the concentrations of P4, LH and FSH reproductive hormones. A random allocation of twenty primiparous Holstein–Friesian cows into four treatment groups that consisted of a wheat-based pelleted basal diet with no supplemental CDCO (control), or a wheat-based pelleted basal diet with CDCO added at 25ml/kg (low), 35ml/kg (medium) and 50ml/kg (high) was employed in an eight-week feeding trial after two weeks of adjustment. Supplementation levels of CDCO and week of data collection were significant sources of variation (P<0.05) that influenced FSH and P4 concentrations. However, there was no significant effect of supplementation on LH concentration (P>0.05). It was apparent that cows in the high (0.459ng/ml), medium (0.367ng/ml) and low (0.251ng/ml) levels of oil treatments had higher mean plasma FSH concentrations compared to the control (0.172ng/ml) cows. It was concluded that the current levels of CDCO can be used in pasture-based dairy systems to increase FSH, but not LH and P4.

Composition of diet modifies colonization dynamics of Campylobacter jejuni in broiler chickens.

To evaluate the impact of diet composition on colonization dynamics of Camp.jejuni and on related physiological parameters in the chicken intestine. A total of 54 1-day-old Ross 308 broiler chicks were randomly divided into three isocaloric and isonitrogenous dietary groups: maize-based (MB), wheat-based (WB) diet and wheat-based diet with NSP-degrading enzyme supplementation (WBES). Chickens were orally infected with 10(8) CFU Camp.jejuni on day 14, and samples (n=6) were collected on 7, 14 and 21days postinfection (DPI), respectively. Colony forming units of Camp.jejuni of caecum and jejunum, short-chain fatty acid (SCFA) concentrations, pH values of the caecum, jejunal histomorphology and viscosity of jejunal chymus were measured. In case of WBES diet, lower Camp.jejuni colonization 14 DPI, higher jejunal viscosity, higher total SCFA concentrations in the caecum and enhanced jejunal histomorphology were observed compared to those measured in chickens fed MB diet. The WBES diet altered Camp.jejuni colonization dynamics in the chicken intestine which resulted by higher SCFA concentrations in the caecum and by the change of gut morphology. Our study proves that diet composition can modify Camp.jejuni colonization depending on sampling time point postinfection.

Supplementation of a wheat-based diet low in phosphorus with microbial 6-phytase expressed in Aspergillus oryzae increases digestibility and plasma phosphorus but not performance in lactating sows

Phosphorus (P) in most diets for sows is poorly digested because pigs do not produce salivary or gastric phytase to hydrolyze P from phytate (inositol hexaphosphate), thus leading to a relatively high amount of P in the manure. An experiment was carried out to study the efficacy of a novel bacterial 6-phytase produced by a strain of Aspergillus oryzae expressing two synthetic genes, both mimicking a phytase gene from a Citrobacter braakii strain. The apparent total tract digestibility coefficient (CATTD) of P, calcium (Ca), crude protein (CP), and gross energy, concentrations of plasma variables, and sow performance were used as response variables. In total, 45 crossbred gestating sows (Large white×Landrace) were individually housed with their litter. Three diets were prepared: (1) positive control (PC; 5.2g available P/kg), regular sow diet containing inorganic P; (2) negative control (NC; 2.0g available P/kg) without inorganic P; and (3) NC+500 FTU/kg diet (NC+PHY). Each diet was fed to 15 sows for 21 days (from day 108 of gestation to day 15 of lactation). To the diets, 3.0g titanium dioxide/kg was added as a marker to determine CATTD of nutrients. Blood samples were collected from the anterior vena cava at day 1 and 15 of lactation to determine plasma minerals (P, Ca, magnesium, copper, iron, and zinc) and plasma urea, glucose, total protein, albumin, and globulin. At day 15 of lactation, CATTD of P did not differ between PC and NC. Phytase supplementation to NC increased (P<0.05) CATTD of P from 0.34 to 0.46 compared to NC, but did not affect CATTD of CP, gross energy, and Ca. On day 1 of lactation, plasma P was 0.66mmol/L lower (P<0.05) in sows fed NC than PC. Phytase supplementation to NC increased (P<0.05) plasma P by 0.40mmol/L on day 1 but not on day 15 of lactation. Sow performance measured as feed intake and body weight changes did not differ between PC and NC or phytase supplementation to NC. In conclusion, phytase supplementation increased P bioavailability in lactating sows. Feeding a P-reduced diet during the first 2 weeks of lactation did not reduce sow performance.

Diet nutrient digestibility and growth performance of weaned pigs fed field pea

Striving for maximum replacement of soybean meal (SBM) with field pea in swine diets is economically important for pork producers. To explore, effects of increasing inclusion of field pea by substituting SBM on diet nutrient digestibility and growth performance of young pigs were evaluated. In total, 260 pigs (8.5kg) starting 1 week after weaning at 19 days of age were fed Phase 1 diets for 2 weeks (day 1–14) and sequentially Phase 2 diets for 3 weeks (day 15–35). Five pelleted wheat-based diets including 0, 100, 200, 300 and 400g yellow field pea (Pisum sativum L., subsp. hortense)/kg in substitution for up to 300g SBM/kg and 100g wheat/kg were fed. Phase 1 and 2 diets were formulated to provide 10.2 and 9.8MJ net energy (NE)/kg, and 1.2 and 1.0g standardised ileal digestible (SID) Lys/MJ NE, respectively. Diets were balanced for NE by reducing dietary canola oil from 48 to 34g/kg and from 27 to 12g/kg for Phase 1 and 2 diets, respectively, and for amino acids by increasing crystalline amino acids. Increasing inclusion of field pea to 400g/kg linearly reduced (P<0.001) the apparent total tract digestibility coefficient (CATTD) of crude protein (CP) by 7% and of gross energy by 2% in Phase 1 diets, but only linearly reduced (P<0.05) CATTD of CP by 1% in Phase 2 diets. Increasing inclusion of field pea to 400g/kg quadratically reduced (P<0.001) calculated diet NE values by 0.4MJ/kg as fed in Phase 1 and linearly reduced (P<0.001) calculated diet NE values by 0.2MJ/kg as fed in Phase 2 diets. The NE value for field pea used for diet formulation was overestimated for pigs immediately after weaning. For day 1–7, increasing inclusion of field pea did not affect average daily feed intake (ADFI) but linearly reduced (P<0.01) average daily gain (ADG) and feed efficiency (G:F). Growth performance was not affected for day 8–14 and 15–21. Increasing inclusion of field pea quadratically increased (P<0.05) ADFI and ADG but did not affect G:F for day 22–28. For day 29–35, increasing inclusion of field pea tended to linearly increase (P<0.10) ADFI, linearly increased (P<0.05) ADG, but did not affect G:F. Overall (day 1–35), increasing dietary inclusion of field pea did not affect ADFI, ADG or G:F. In conclusion, up to 400g/kg field pea can entirely replace SBM in nursery diets formulated to equal NE value and SID amino acid content without detrimental effects on growth performance after a 7-day adaptation.

Phytase supplementation of maize-, sorghum- and wheat-based broiler diets with identified starch pasting properties influences phytate (IP6) and sodium jejunal and ileal digestibility

The effects of phytase supplementation on growth performance, nutrient utilisation, starch and protein digestive dynamics in broiler chickens offered maize-, sorghum- and wheat-based diets were determined in a previous study (Liu et al., 2014). Responses to phytase were most pronounced in maize-based diets, which suggest that more phytate was degraded in these diets. Relevant retained samples of grain, diets and digesta from four small intestinal segments were retrospectively analysed for concentrations of phytate, sodium and starch pasting properties to investigate the hypothesis that phytate in maize-based diets was more completely degraded by exogenous phytase. Exogenous phytase significantly (P<0.001) degraded dietary phytate in the proximal jejunum, distal jejunum, proximal ileum and distal ileum and increased distal ileal phytate digestibility coefficients from 0.238 to 0.631. There were significant differences (P<0.001) between diets based on maize (0.515), wheat (0.449) and sorghum (0.340) for distal ileal phytate digestibility coefficients. Phytase accelerated phytate disappearance rates from all four segments and increased distal ileal phytate disappearance rates from 201 to 535mg/bird/day. This was significantly more pronounced in maize (459mg/bird/day) than in diets based on sorghum (301mg/bird/day) and wheat (343mg/bird/day). Sodium digestibility coefficients were significantly improved (P<0.01) by exogenous phytase in proximal jejunum, distal jejunum and proximal ileum. Exogenous phytase significantly influenced starch properties of experimental diets determined by rapid visco-analysis (RVA). There were significant negative correlations between RVA setback viscosity of starch in experimental diets and starch digestibility coefficients at the distal jejunum (r=−0.438; P<0.01) and proximal ileum (r=−0.591; P<0.001) determined in the Liu et al. (2014) study. Distal ileal phytate digestibility coefficients appeared to be higher in non-supplemented, maize-based diets (0.349) than in diets based sorghum (0.128) and wheat (0.239) thus the likelihood is that phytate in maize-based diets was more readily degraded by endogenous, mucosal phytase in the small intestine. Consideration is given to the possibilities that location of phytate within grains influences phytate degradation and that the relatively low sodium concentrations in maize-based diets may have contributed to the more robust responses to exogenous phytase observed.

Effects of wheat cultivar, metabolizable energy level, and xylanase supplementation to laying hens diet on performance, egg quality traits, and selected blood parameters

A 2 x 2 x 2 factorial arrangement of treatments was conducted to evaluate the effects of two dietary apparent metabolizable energy (AME) levels (2,720 and 2,580 kcal kg-1 diet) and enzyme (0 and 0.3 g kg-1 diet, Grindazym® GP 15,000 with mostly xylanase activity) supplementation on the performance of laying hens fed diets based on two wheat cultivars (Marvdasht and Sardari). Experimental diets were formulated to have a constant energy to protein ratio and were fed to 65-wk-old Lohmann LSL-Lite laying hens for 7 wk. The lower level of AME reduced egg production and egg mass (p&lt;0.05) and increased feed conversion ratio (p&lt;0.05). Enzyme addition increased feed intake of the birds fed a diet with Sardari cultivar (p&lt;0.05) but had no effect on feed intake of the birds fed a diet with Marvdasht cultivar (p&gt;0.05). Nevertheless, birds receiving diets based on Marvdasht cultivar had higher feed intake and egg mass than that of those receiving diets based on Sardari cultivar (p&lt;0.05). The birds fed diets based on Marvdasht cultivar produced less undesired eggs and had better yolk color as compared with the birds fed diets based on Sardari cultivar (p&lt;0.05). The serum concentration of glucose increased by enzyme supplementation when birds receiving lower AME level (p&lt;0.05). These results indicate that enzyme supplementation may have a positive effect on the feed intake of laying hens when fed on wheat-based diets; however, this effect is cultivar dependent and does not necessarily mean that enzyme supplementation always benefit production.

Contribution of protein, starch, and fat to the apparent ileal digestible energy of corn- and wheat-based broiler diets in response to exogenous xylanase and amylase without or with protease

The ileal energy contribution of protein, starch, and fat in response to 2 exogenous enzyme combinations was studied in 2 digestibility assays with 21- (experiment 1; 432 birds) and 42-d-old (experiment 2; 288 birds) Ross 308 broiler chickens. A 2 × 2 × 3 factorial arrangement of treatments with 2 base grains (corn or wheat), without or with high fiber ingredients (corn distillers dried grains with solubles and canola meal), and 3 enzyme treatments was implemented. Enzyme treatments, fed from 12 to 21 d or 32 to 42 d, were 1) without enzymes, 2) with xylanase from Trichoderma ressei (2,000 U/kg) and amylase from Bacillus licheniformis (200 U/kg; XA), or 3) with XA plus protease from Bacillus subtilis (4,000 U/kg; XAP). All diets contained Escherichia coli phytase (500 FTU/kg). Apparent ileal digestibility (AID) of protein, starch, and fat, as well as the apparent ileal digestible energy, were determined using titanium dioxide as inert marker. A generalized mixed model was used to test main effects and 2-way interactions at P < 0.05. An enzyme × grain interaction was detected for AID of starch at 21 and 42 d, and AID of fat at 21 d, with greater effects of enzymes in wheat-based compared with corn-based diets, but significant increments due to enzymes compared with controls in both diet types. Apparent ileal digestibility of fat at 42 d increased with enzyme supplementation compared with the control treatments. The XA and XAP treatments gradually (P < 0.05) increased AID of protein at 21 d, but only XAP increased AID of protein compared with the control at 42 d. Compared with the controls, XA increased AID energy by 52 or 87 kcal, and XAP by 104 or 152 kcal/kg of DM at 21 or 42 d, respectively. The caloric contribution of starch, fat, and protein were affected differentially by base grain and the presence of fibrous ingredients at 21 and 42 d of age.

Effects of the composition of the basal diet on the evaluation of mineral phosphorus sources and interactions with phytate hydrolysis in broilers

The objectives of this study were to determine the availability of P from mineral phosphate sources by using different basal diets and measurement of P retention and prececal (pc) P digestibility as well as pc myo-inositol phosphate (InsP) degradation in broilers. Semi-synthetic and corn-soybean meal-based basal diets were used in experiment 1, and corn-based and wheat-based basal diets were used in experiment 2. Anhydrous monosodium phosphate (MSPa) or monocalcium phosphate monohydrate (MCPh) was supplemented to increment the P concentration by 0.05, 0.10, and 0.15% or by 0.075 and 0.150% in experiments 1 and 2, respectively. Titanium dioxide was used as an indigestible marker. Diets were pelleted through a 3-mm screen. In experiment 1, retention was measured based on total excreta collection from 20 to 24 d of age using 7 replicated birds per diet. In experiment 2, digesta from the terminal ileum was collected from 22-d-old broilers penned in groups of 19 with 5 replicated pens per diet. The P retention response to supplemented MSPa did not differ between the 2 basal diets in experiment 1. The response in pc P digestibility to MCPh supplements also did not differ between the 2 basal diets in experiment 2, as calculated by linear regression analysis. Hydrolysis of InsP6 measured on both the excreta and pc levels was high in the basal diets without a mineral P supplement. Mineral P supplementation significantly decreased (P < 0.05) InsP6 hydrolysis from the InsP-containing diets in both experiments. Thus, the choice of the basal diet did not affect the evaluation of the supplemented mineral P source. However, calculated values for mineral P sources need to be adjusted for the decline in hydrolysis of InsP contained in the basal diet that results from the P supplement.

Dietary nano-chromium tripicolinate increases feed intake and decreases plasma cortisol in finisher gilts during summer.

Chromium (Cr) is an essential mineral element and has been used in pig diets to improve growth performance, insulin sensitivity, immune response and carcase traits and to reduce heat or other stress responses. The aims of thiss study were to determine the impact of nano-sized chromium tripicolinate (nCrPic) on growth performance, feed efficiency and carcase characteristics of finisher gilts during the summer period. A total of 60 finisher Large White x Landrace gilts were stratified on initial weight and then within strata randomly allocated into two treatment groups in three replicates during mid-summer for 28 days. All pigs were housed in individual pens and had ad libitum access to feed and water. Pigs were fed either a control finisher diet (wheat-based diet containing 13.8 MJ digestible energy (DE) per kilogram and 0.56 g available lysine/MJ DE) or a control diet containing 400 ppb Cr as nCrPic. Dietary nCrPic supplementation increased feed intake by 6 % over the entire study (P = 0.05). In particular, dietary nCrPic increased average daily feed intake (ADFI) by 8 % (P = 0.02) during the final 2 weeks of the study. Moreover, dietary nCrPic tended to improve average daily feed (ADFI) over the entire study (P = 0.09). However, there were no significant effects of nCrPic on feed conversion ratio (FCR), final weight, hot standard carcase weight (HCWT), P2 depth or dressing percentage. Plasma cortisol was decreased by 25 % (P = 0.06) by dietary nCrPic supplementation. However, there were no effects of nCrPic on plasma glucose, insulin and nonesterified fatty acids (NEFA), might because of the higher feed intake. In conclusion, this study demonstrates that dietary nCrPic supplementation at 400 ppb can increase feed intake in finisher gilts during mid-summer, suggesting that nCrPic can ameliorate some of the negative effects of heat stress in pigs, possibly via decreased of circulating cortisol.

&lt;b&gt;Influence of xylanase and vitamin A in wheat-based diet on performance, nutrients digestibility, small intestinal morphology and digesta viscosity in broiler chickens

The effect of wheat-based diet (WBD), supplemented with xylanase and surplus vitamin A, on performance, nutrient digestibility, intestinal morphology and digesta viscosity of broiler chickens was investigated. Based on a completely randomized design, 240-day-old chickens were randomly divided into six experimental diets and four replications with 10 chickens each. Experimental diets consisted of corn-based diet (CBD) (T1), WBD with routine amounts of vitamin A (9000 IU kg-1) (T2), T2 without vitamin A in premix (T3), T2 + 6000 IU kg-1 vitamin A (T4), T2 + 420 IU kg-1 xylanase (T5), and T2 + 6000 IU kg-1 vitamin A + 420 IU kg-1 xylanase (T6). For Feed Conversion Rate (FCR) between day 1 and 21 and between day 21 and 42 WBD supplemented with vitamin A and enzyme was less than CBD (p < 0.05). Also, supplementation of surplus vitamin A singly, and vitamin A and enzyme improved digestibility of crude protein (CPD) and crude fat (CFD) than WBD with routine amounts of vitamin A (p < 0.05). The villus (duodenum, jejunum and ileum) was longer (p < 0.05) in broilers fed on diet supplemented with vitamin A and enzyme than those with CBD. It may be concluded that enzyme and vitamin A supplementation to WBD may improve mentioned parameters.

Effects of phytase supplementation on growth performance, nutrient utilization and digestive dynamics of starch and protein in broiler chickens offered maize-, sorghum- and wheat-based diets

To investigate the effects of phytase supplementation on growth performance, nutrient utilization and digestive dynamics of starch and protein, a study was conducted using 288 male Ross 308 chicks (6 treatments with 8 replicate cages of 6 birds). Birds were offered steam-pelleted diets based on maize, sorghum or wheat, without or with phytase supplementation, from 7 to 27 days post-hatch. Experimental diets were formulated to be equivalent for energy, protein/amino acids and were P-adequate. Digesta samples from proximal jejunum, distal jejunum, proximal ileum and distal ileum were collected in their entirety at day 27. Digestion rates of starch and protein were determined by fitting exponential mathematical model to apparent digestibility coefficients with mean retention times in each small intestinal segment. The growth performance of birds offered maize and sorghum were comparable but those offered wheat-based diets were inferior. Phytase improved weight gain (P<0.001), feed intake (P<0.001) and feed conversion (P<0.05) in maize-, sorghum- and wheat- based diets, although the most pronounced improvements tended to be for maize. There were grain type-phytase interactions (P<0.01) for nutrient utilization (AME, N retention, AMEn) where substantial phytase responses were observed for maize but not for sorghum- and wheat-based diets. Phytase did not influence digestion rates of starch and protein (P>0.05), but it significantly increased disappearance rates of starch in maize-based diets (P<0.05). In conclusion, phytase improved weight gain and feed conversion efficiency in maize-, sorghum- and wheat-based diets with more pronounced response in maize-based diets. Moreover, phytase also significantly enhanced nutrient utilization in maize-based diets.

Green manure addition to soil increases grain zinc concentration in bread wheat.

Zinc (Zn) deficiency is a major problem for many people living on wheat-based diets. Here, we explored whether addition of green manure of red clover and sunflower to a calcareous soil or inoculating a non-indigenous arbuscular mycorrhizal fungal (AMF) strain may increase grain Zn concentration in bread wheat. For this purpose we performed a multifactorial pot experiment, in which the effects of two green manures (red clover, sunflower), ZnSO4 application, soil γ-irradiation (elimination of naturally occurring AMF), and AMF inoculation were tested. Both green manures were labeled with 65Zn radiotracer to record the Zn recoveries in the aboveground plant biomass. Application of ZnSO4 fertilizer increased grain Zn concentration from 20 to 39 mg Zn kg−1 and sole addition of green manure of sunflower to soil raised grain Zn concentration to 31 mg Zn kg−1. Adding the two together to soil increased grain Zn concentration even further to 54 mg Zn kg−1. Mixing green manure of sunflower to soil mobilized additional 48 µg Zn (kg soil)−1 for transfer to the aboveground plant biomass, compared to the total of 132 µg Zn (kg soil)−1 taken up from plain soil when neither green manure nor ZnSO4 were applied. Green manure amendments to soil also raised the DTPA-extractable Zn in soil. Inoculating a non-indigenous AMF did not increase plant Zn uptake. The study thus showed that organic matter amendments to soil can contribute to a better utilization of naturally stocked soil micronutrients, and thereby reduce any need for major external inputs.

Evaluation of free water and water activity measurements as functional alternatives to total moisture content in broiler excreta and litter samples

Litter moisture contents vary greatly between and within practical poultry barns. The current experiment was designed to measure the effects of 8 different dietary characteristics on litter and excreta moisture content. Additionally, free water content and water activity of the excreta and litter were evaluated as additional quality measures. The dietary treatments consisted of nonstarch polysaccharide content (NSP; corn vs. wheat), particle size of insoluble fiber (coarse vs. finely ground oat hulls), viscosity of a nonfermentable fiber (low- and high-viscosity carboxymethyl cellulose), inclusion of a clay mineral (sepiolite), and inclusion of a laxative electrolyte (MgSO4). The 8 treatments were randomly assigned to cages within blocks, resulting in 12 replicates per treatment with 6 birds per replicate. Limited effects of the dietary treatments were noted on excreta and litter water activity, and indications were observed that this measurement is limited in high-moisture samples. Increasing dietary NSP content by feeding a corn-based diet (low NSP) compared with a wheat-based diet (high NSP) increased water intake, excreta moisture and free water, and litter moisture content. Adding insoluble fibers to the wheat-based diet reduced excreta and litter moisture content, as well as litter water activity. Fine grinding of the oat hulls diminished the effect on litter moisture and water activity. However, excreta moisture and free water content were similar when fed finely or coarsely ground oat hulls. The effects of changing viscosity and adding a clay mineral or laxative deviated from results observed in previous studies. Findings of the current experiment indicate a potential for excreta free water measurement as an additional parameter to assess excreta quality besides total moisture. The exact implication of this parameter warrants further investigation.

Effects of broiler breeder-feeding programme and feeder space change at photostimulation using maize- or wheat-based diets on eggshell properties and progeny bone development

1. The effects of diet type, feeding programme and fast- or slow-feed allocation in fast-feathering Cobb 500 broiler breeder hens on eggshell properties and broiler progeny bone development were investigated in a 2 × 2 × 2 factorial experiment.2. The birds were fed on either maize- or wheat-based diets during rearing and production and on a fast- or slow-feed allocation programme from 14 to 29 weeks of age. At 22 weeks, 69 females from each pen were placed in a layer house where feeder space (FS) either remained similar or was increased.3. Eggs produced at 33 weeks were incubated, eggshell conductance (G) was determined and a sample of 14 chicks from each treatment combination was taken to obtain bone traits at hatching.4. Diet type did not influence G, yolk-free body weight (BW), residual yolk weight or relative asymmetry (RA) of any bilateral traits of leg bones of hatchlings. However, breeder diet type was involved on two-way and three-way interaction effects on progeny leg bone traits.5. Breeders feed restricted according to the slow-feeding programme laid eggs with greater G compared to those managed with the fast-feeding programme, but there was no effect of feeding programme on progeny bone traits at hatching.6. Eggs from breeders given more FS at photostimulation had greater G than those from breeders provided with similar FS. Maternal FS change did not influence hatchling yolk-free BW; however, breeders given more FS produced progeny with heavier tibias and shanks and longer femurs compared with those provided with similar FS, but only when breeders were fed on maize. Moreover, increased maternal FS at photostimulation was associated with an increased RA of femur length in the progeny.7. It was concluded that breeder FS change at photostimulation influenced eggshell conductance and consistently affected bone development of the broiler progeny.

Growth performance, nutrient utilization, and digesta characteristics in broiler chickens fed corn or wheat diets without or with supplemental xylanase

Efficacy of supplemental xylanase on growth performance, nutrient utilization, and digesta characteristics in broiler chickens fed corn- or wheat-based diets was investigated. In experiment 1, 192 male broilers (8 birds/pen; n = 6) were fed 4 diets (corn or wheat without or with 1,250 xylanase units/kg) in 2 phases (starter, d 0–21 and grower, d 22–42). There was no interaction (P > 0.05) between diet and xylanase on performance (d 0–42). Wheat diets resulted (P < 0.01) in better performance than corn diets, whereas xylanase-fed birds had improved (P < 0.01) BW gain (2,457 vs. 2,275 g) and feed per gain (1.677 vs. 1.762) relative to birds not fed xylanase. In experiment 2, TiO2 (0.3%) was added in starter diets used in experiment 1, allocated to 13-d-old broiler chicks (n = 6) housed in cages (6 birds/cage) and fed up to d 21. Excreta samples were obtained from d 17 to 20 and birds were euthanized on d 21 for digesta. Corn diets had a greater concentration (10.7 vs. 9.8%) of insoluble nonstarch polysaccharides (NSP) than wheat diets, which in turn had more than twice the concentration of soluble NSP. There was an interaction (P < 0.03) between diet type and xylanase on jejunal digesta viscosity but not (P > 0.10) on apparent ileal digestibilities of nutrients, cecal volatile fatty acids, and AMEn. In this context, diet type influenced (P < 0.05) cecal volatile fatty acids and retention of nutrients and fiber but did not affect (P = 0.45) AMEn. In contrast, xylanase-fed birds showed higher (P < 0.05) ceca digesta acetic acid, apparent ileal digestibilities of nutrients, and retention of components. As a result, birds fed xylanase had higher AMEn (3,059 vs. 2,995 kcal/kg; P < 0.01) compared with birds not fed xylanase. Although wheat diets had superior growth performance, the AMEn was similar in both diets. Xylanase improved growth performance and AMEn independent of diet type, suggesting hydrolysis of both soluble and insoluble NSP.

Effects of exogenous xylanase on performance, nutrient digestibility, volatile fatty acid production and digestive tract thermal profiles of broilers fed on wheat- or maize-based diet

1. A previous experiment reported that caecal temperature was negatively correlated with d 49 feed conversion ratio (FCR). This increased temperature in the caeca may indicate a prebiotic effect. An experiment was designed to investigate whether caecal temperature was affected in diets based on maize and whether other portions of the tract were affected.2. A total of 25 Ross 308-d-old male broilers were allocated to each of 8 replicate pens per treatment. Treatments followed a 2 × 3 factorial design: two diets based on wheat or maize and three levels of enzyme addition, 0, 16 000 or 32 000 BXU/kg. Growth performance was assessed between d 1 and 49. Digestibility measurements were taken at d 28 and 49. On d 49, the excised small and large intestine of each bird was thermally imaged, weighed and volatile fatty acids (VFA) measured.3. On d 28 and d 49, birds on the maize diets had higher feed intake and weight gain than those offered wheat diets. Additionally, on d 28, birds that received the maize diet had lower FCR than those offered the wheat diet. Enzyme improved FCR at d 49, independently of cereal. On d 28, enzyme improved the coefficient of apparent ileal DM digestibility and the coefficient of apparent ileal nitrogen digestibility. Enzyme only improved apparent ileal digestible energy in wheat-based diets (interactive term). On d 49, all digestibility parameters were improved by enzyme. Enzyme increased gizzard weight in maize-fed birds and the caeca of those fed wheat were heavier. The higher enzyme dose decreased duodenal temperature. In summary of VFA data, wheat-based diets produced more total VFAs and the total amount also increased with enzyme.4. It appears from this study that there is equal potential in both wheat and maize diets for xylanase to improve performance of broilers probably through different mechanisms.