AMEn Of Diet Research Articles

Viscosity negatively affects the nutritional value of blue lupin seeds for broilers

This study examines the impact of Lupinus angustifolius variety (C) and inclusion level (L) in broiler diets on the nutritional value, viscosity of ileal digesta and activity of gut microbiota. The experiment was conducted on 154 female 21-day-old broilers, allocated to 11 groups (kept individually). A reference lupin-free diet and 10 test diets containing one of five lupin seeds; Kadryl, Regent, Dalbor, Bojar and Tango, mixed with the reference diet at a ratio of 25 : 75 or 32 : 68 dry matter (DM) (low or high level of inclusion) were prepared. Diets were fed for 6 days, excreta were collected over last 4 days. Apparent metabolizable energy corrected to zero N balance (AMEN) of diets and AMEN of lupin seeds were calculated. Birds were sacrificed, ileal and caecal digesta were pooled by segments from two birds, and the activity of bacterial enzymes was determined. The ileal digesta viscosity was measured immediately (ileal viscosity immediate (IVI)) or after 6 days storage at −18°C (ileal viscosity frozen). AMEN of test diets were lower than the reference diet. Lupin AMEN values ranged from 6.04 MJ/kg DM for Regent at high level to 9.25 MJ/kg DM for Bojar at low level. High inclusion level numerically decreased AMEN value in all cultivars, except for Kadryl, for which it increased (significant C×L interaction). The IVI value was 2.6 mPa·s in the reference group, but ranged from 6.3 to 21.7 mPa·s in lupin-fed birds. It increased significantly with level for Regent, Dalbor and Tango but not for the other two cultivars (significant C×L interaction). There was a negative correlation between IVI and: apparent total tract N retention, fat digestibility from test diets, AMEN of diets and lupins. Ileal viscosity immediate was positively correlated with the activity of ileal α- and β-glucosidase and negatively with ileal α-galactosidase and caecal α-glucosidase. Ileal viscosity frozen ranged from 3.2 to 5 mPa·s and it was not correlated with lupins AMEN. This suggests that the digesta viscosity caused by narrow-leafed lupin is detrimental to its nutritional value and interfere with the gut microbial activity. In addition, the lupins viscosity was measured by two in vitro methods: the water extract viscosity (WEV) method and after incubation in conditions imitating in vivo digestion (enzyme-treated extract viscosity (EEV)). In vivo viscosity was weakly reflected by in vitro measurements as there was no correlation between IVI and WEV or EEV. Overall, findings suggest that the different cultivars of narrow-leafed lupin may have different value for practical application in broiler diets.

The effect of protease, amylase, and nonstarch polysaccharide-degrading enzyme supplementation on nutrient utilization and growth performance of broiler chickens fed corn-soybean meal-based diets

A study was conducted to determine if amylase and protease addition would improve nutrient digestion during the first 2 wk of growth. The experimental treatments included a control corn-soybean meal-based diet and diets supplemented with either amylase or amylase plus protease. No effect of enzyme supplementation was observed on BW gain and feed conversion ratio. This was corroborated by similar ileal starch and protein digestibility values, which averaged 96.8, 96.8, and 96.9% and 83.9, 80.1, and 79.6%, respectively, for the control and for the amylase or amylase plus protease supplemented diets. Total tract digestibility of starch averaged 97.8, 97.7 and 97.7% for the 3 diets and was followed by a similar diet with AMEn values of 3,129, 3,129, and 3,106 kcal/kg. In another study, a 23 factorial arrangement of 8 dietary treatments was used to evaluate the effect of corn particle size (conventional or coarse vs. fine) and the addition of a nonstarch polysaccharide enzyme, amylase, or both on growth performance and nutrient utilization of broiler chickens from 1 to 21 d of age. Chickens fed a diet containing a conventionally ground corn (geometric mean diameter of 736 µm) showed higher (P < 0.001) BW gain (808 vs. 750 g/bird) and lower feed conversion ratio (1.27 vs. 1.32) than those consuming a fine corn-containing diet (geometric mean diameter of 482 µm). This was further substantiated by a lower AMEn content (2,852 vs. 2,972 kcal/kg). Addition of amylase had no effect on growth performance of chickens fed a conventional corn-containing diet, but improved BW gain, feed conversion ratio, and diet AMEn in those fed the finely ground corn, possibly due to increased starch digestion in the upper gut. Addition of nonstarch polysaccharide enzymes was effective for both diets, with the most pronounced effects observed in feed converstion ratio for the conventional corn-containing diet (1.27 vs. 1.23) and BW gain (750 vs. 789 g/bird) for the fine corn-containing diet. This was followed by the same magnitude of difference in diet AMEn content, which increased from 2,972 to 3,042 and 2,852 to 3,009 kcal/kg following enzyme addition.

Effect of supplementing direct-fed microbials on broiler performance, nutrient digestibilities, and immune responses

Direct-fed microbials (DFM) are used to improve livestock health and performance. The effects of 2 DFM products, a blend of 3 Bacillus strains (DFMB) and a Propionibacteriumspp. (DFMP), on broiler performance, nutrient utilization, and immune responses were investigated. Day-old (n = 120) male broilers were divided into 24 groups of 5 birds and fed 3 wheat-based diets in mash form (8 groups per diet) from d 1 to 22. The control diet was fed without or with 7.5 × 10(4) cfu/g of either DFMB or DFMP. From d 19 to 21 fecal samples were collected for determination of total tract apparent retention (TTAR) of nutrients and AMEn. On d 21, feed intake and BW were determined. On d 22, 5 birds per treatment were killed by cervical dislocation to collect jejunal and ileal contents for determination of digesta viscosity and apparent ileal digestibility (AID) of nutrients, respectively, and ileum, cecal tonsil, and spleen tissues for Toll-like receptors (TLR) and cytokine expressions. Compared with the control, DFM did not affect BW gain and feed intake but DFMP reduced G:F (P < 0.01). Compared with the control (2,875 kcal/kg), birds fed on DFMB and DFMP had higher AMEn (2,979 and 2,916 kcal/kg, respectively; P < 0.05), whereas both DFM reduced the AID of DM (P < 0.001) and CP (P < 0.01). Furthermore, DFMP reduced TTAR of NDF (29.0 vs. 18.4%; P < 0.001), whereas both DFM increased TTAR of DM and fat (P < 0.001). Supplementing DFMP downregulated ileal expression of TLR-2b, IL-2, IL-4, IL-6, IL-10, and IL-13, whereas DFMB downregulated TLR-2b, IL-2, IL-4, and IL-6 in all 3 tissues, IL-10 in the spleen, and upregulated IL-13 in the spleen. In conclusion, the DFM did not improve performance but increased the AMEn of diet by possibly increasing DM and fat retention. Overall, both DFM showed an antiinflammatory effect in the ileum, but DFMB had more effects on local and systemic immunity than DFMP.

Buckwheat bran (Fagopyrum esculentum) as partial replacement of corn and soybean meal in the laying hen diet

The effect of partial substitution of corn (−20%) and soybean meal (−10%) with buckwheat bran (+30%) (Fagopyrum esculentum Moench) in the diet of ISA-Brown hens was investigated in sixteen 74-week old hens, housed in couple wire cages and submitted to a 16 h light:8 h dark photoperiod. The following traits were measured: body weight, egg production, egg mass, egg quality, feed intake, feed conversion, comparative palatability of ingredients and digestibility of diet. χ2 and non-parametric tests were used for production rate and yolk color score, respectively. ANOVA was used for all other parameters. Comparative choice of buckwheat, corn and soy was checked under different forms in 3 free choice tests. Results show that egg production rate (43.3% vs 50.5%; P<0.05) and feed intake (78.3±0.68 eggs/hen d vs 87.8±0.68 eggs/hen d; P<0.05) increased with the partial introduction of buckwheat bran in the diet. There was no difference in feed conversion between treatments. Nutrient balance confirmed that AMEn of diet was deeply lowered by the buckwheat bran use (6.5 MJ/kg vs 10.1 MJ/kg), due to the high fibre content of buckwheat bran (263 g/kg). Maize was always the most preferred ingredient, buckwheat bran was consumed more than expected in absence of any preference, and soybean was the food least chosen. Buckwheat bran can be used as an ingredient feed for low-producing laying hens; it induces a feed-intake increase, partially balanced by improved egg-production rates and a tendency to better albumen Haugh units.

Supplementation of β-mannanase to starter and grower diets for broilers

Kong, C., Lee, J. H. and Adeola, O. 2011. Supplementation of β-mannanase to starter and grower diets for broilers. Can. J. Anim. Sci. 91: 389–397. Two experiments were conducted to investigate the efficacy of β-mannanase on ileal nutrient digestibility, total tract utilization of dry matter (DM), N, energy, and apparent metabolizable energy (AME, exp. 1), and growth performance (exp. 2) of birds fed practical corn-soybean meal (SBM)-based diets. In each experiment, 192 male broilers were assigned to four diets arranged in a 2×2 factorial of energy level [corn-SBM-based diet that met or exceeded NRC nutrient requirements (AE) or low energy (LE) diet containing 100 kcal of ME kg−1 less than the AE diet] and enzyme supplementation (with or without β-mannanase) for 21 d. Supplementing the diet with β-mannanase increased the birds’ apparent ileal DM digestibility of the experimental diets (P&lt;0.05), whereas there was no effect of energy level. Neither β-mannanase supplementation nor energy level had any effect on apparent ileal digestibility of any of the amino acids. The interaction between enzyme and energy levels was not significant for any criteria measured in the excreta except for DM (P=0.05). Addition of β-mannanase improved (P&lt;0.01) the apparent total tract utilization of DM and energy in the broilers, and there was the same trend (P=0.06) for N utilization. Supplementing the diet with β-mannanase also improved the AME and AMEn of diets by 4.6 and 5.0%, respectively. For all growth performance responses in exp. 2, the interaction between enzyme and energy levels was not significant. During the starter period (day 2 to 22 post-hatch), β-mannanase supplementation significantly (P&lt;0.05) increased the body weight (BW) gain of birds. During the grower period (day 22 to 44 post-hatch) and for the overall period there was no significant difference in BW gain or feed intake of birds regardless of energy level and β-mannanase supplementation. There were no dietary effects on feed efficiency of birds during the starter and the grower periods, whereas the birds fed AE diets had higher feed efficiency (P&lt;0.01) than the birds fed LE diets. The results indicate that supplementing with β-mannanase may improve gain and energy utilization of broilers, whereas it may not affect ileal amino acid digestibility.

Growth performance and nutrient utilization of broiler chickens fed diets supplemented with phytase alone or in combination with citric acid and multicarbohydrase

An experiment was conducted to determine the effect of supplementing a corn-soybean meal-based diet with phytase alone or in combination with citric acid (CA) or multicarbohydrase, a preparation containing nonstarch polysaccharide-degrading enzymes, or both, on growth performance, nutrient utilization, and bone mineralization. A total of 360 one-day-old broiler chicks were assigned to 6 dietary treatments, consisting of 12 pens of 5 birds each, and were fed experimental diets from 1 to 21 d of age. The diets included a positive control (0.46% nonphytate P; 1.1% Ca) and a negative control (NC; 0.26% nonphytate P; 0.89% Ca) without or with phytase (600 U/kg) alone, phytase plus CA (5 g/kg), phytase plus multicarbohydrase (Superzyme OM; 0.6 g/kg), or phytase (Ronozyme P-CT) plus CA and multicarbohydrase. Birds fed the positive control diet had higher (P<0.05) BW gain (764 vs. 594 g/21 d) and tibia ash content (50.0 vs. 38.3%) than those fed the NC diet. Phytase improved (P<0.05) BW gain (632 g/21 d), which increased further (P<0.05) to 673 g/21 d for the phytase plus multicarbohydrase diet. In contrast to phytase alone, phytase plus multicarbohydrase supplementation improved (P<0.05) feed conversion ratio of the NC diet from 1.37 to 1.32. Tibia ash content for the NC diet increased (P<0.05) from 38.3 to 42.4% due to phytase addition. Phytase improved (P<0.05) ileal digestibility of P from 29.5 to 43%, and the addition of CA or multicarbohydrase, or both, to a phytase-supplemented diet further increased (P<0.05) P digestibility to 51.5, 53.4, and 54.3%, respectively. Phytase addition improved (P<0.05) diet AMEn content from 2,959 to 3,068 kcal/kg, which tended (P<0.06) to increase further with CA (3,150 kcal/kg) or multicarbohydrase (3,142 kcal/kg) addition. No beneficial interactions were detected between CA and multicarbohydrase for all response criteria measured. Results show that addition of multicarbohydrase to the phytase-supplemented broiler diets improved nutrient utilization and growth performance.

Effect of Gelatinizing Dietary Starch Through Feed Processing on Zero- to Three-Week Broiler Performance and Metabolism

Feed manufacturing produces physical and chemical changes in ingredients, including the gelatinization of starch. The effect of gelatinized starch on animal metabolism and subsequent performance has been inconsistent in past research. In the current study, corn was processed through different procedures (pelleting and extrusion) and substituted for unprocessed corn at varying levels (one-third, two-thirds, and three-thirds) in complete diets. Complete diets were not further processed. The objective of the study was to evaluate different levels of starch gelatinization produced by different processes on broiler performance through 3 wk of age. Pelleted and extruded corn had analyzed starch gelatinizations of 29 and 92%, respectively. Each of the 6 processed corn diets and a control diet (ground unprocessed corn) was fed to 8 replicate pens of 10 male broilers. A second experiment determined AME n of each diet. Broilers fed diets containing pelleted corn had lower feed intake (P = 0.0439) and higher gain to feed (G:F, P = 0.0028) than broilers fed diets containing extruded corn. Gain-to-feed ratio was not affected when pelleted or extruded corn was increased in diets. The AMEn of diets increased as pelleted or extruded corn inclusion increased (P = 0.0331 and 0.0009, respectively). Diets containing pelleted or extruded corn pooled by inclusion level did not improve AMEn or G:F compared with the control diet. However, diets containing pelleted or extruded corn pooled by inclusion level increased live weight gain (LWG, P = 0.04 and 0.0038, respectively) compared with the control in part due to increased feed intake.

Metabolizable Energy of Layer Diets Containing Regular or Heat-Treated Flaxseed

Two experiments were conducted to determine whether the AMEn of diets containing flaxseed could be improved by subjecting flaxseed or flax-based diets to various heat treatments. In Experiment 1, a corn-soybean diet was prepared, and a flaxseed premix was added to produce a diet containing either 10% heat-treated (extruded) flaxseed or 10% flaxseed that was not heat treated. Experiment 2, utilized a commercial diet containing 10% flaxseed that had been processed through an expander. Extruding flaxseed improved its AMEn; however, the AMEn of the expanded diet was significantly (P < 0.05) less compared to a diet that was merely pelleted. The amount of α-linolenic acid (LNA) and docosahexaenoic acid (DHA) deposited in the eggs from hens fed extruded flaxseed was also significantly (P < 0.05) less compared to the hens fed a conventional pelleted diet.

Studies on the metabolizable energy content of ground full-fat flaxseed fed in mash, pellet, and crumbled diets assayed with birds of different ages

Four experiments were carried out to determine the AMEn of ground flaxseed in chickens of different ages and to study the effect of feeding flaxseed in pelleted or crumbled diets on flaxseed AMEn. A corn-soybean meal basal diet was prepared, in which the energy-yielding ingredients were substituted with ground flaxseed at 5, 10, 15, or 20%. Experiments 1, 2, and 3 consisted of these five dietary treatments replicated six times using 9-d-, 6-wk-, and 79-wk-old birds, respectively. A total collection procedure was used to measure diet AMEn, and linear regression analyses were used to calculate the AMEn value of flaxseed for birds at different ages. Experiment 4 involved birds fed either a basal or a 10% ground flaxseed diet prepared as mash, pellets, or crumbles. The flaxseed AMEn values obtained with 9-d- and 6-wk-old chickens were 2,118 and 2,055 kcal/kg, respectively. These values contrast with those of Experiments 3 and 4, in which mature roosters were fed mash diets with AMEn values of 3,560 and 3,654 kcal/kg, respectively. In Experiment 4, a significant improvement in flaxseed AMEn was observed when diets were pelleted or crumbled (4,578 and 4,277 kcal/kg, respectively). We concluded that the difference in AMEn of flaxseed observed in young birds vs. that found in mature birds was likely due to a greater tolerance of the latter to flaxseed, with less evidence of diarrhea. Feeding flaxseed in pellet or crumbled diets can significantly increase AMEn value.

Effect of Dietary Lipase Enzyme on Gut Morphology, Gastric Motility, and Long-Term Performance of Broiler Chicks

Three experiments were conducted to test a previously described anorexic effect of graded dietary supplements of Pancreatic® lipase enzyme on gut structure, gastric motility, and long-term performance of broiler chicks. In Experiment 1, dietary Pancreatic® enzyme was used at graded levels of 0, 0.214, 0.429, 0.643, 0.857, and 1.071% to test the effect of this enzyme on gut structure, whereas Experiment 2 was designed to test its effect at 0, 0.268, 0.536, 0.804, 1.071, and 1.339% on gastric motility. The histological examination of the small intestine and a cineradiographic study of birds fed diets supplemented with lipase enzyme failed to detect any difference in gut structure, and there was no apparent adverse effect on gastric motility. Experiment 3 was conducted to test the effect of graded supplements of Pancreatic® enzyme on performance of 300 male broiler chicks raised for 6 wk to determine whether the enzyme had any long-term effect on performance characteristics, especially feed intake. Only starter diets (0 to 21 d) were supplemented with 0, 0.375, 0.750, or 1.125% enzyme, and each diet was represented by three replicate pens of 25 male chicks each. Subsequent diets did not contain any enzyme. During the first 3 wk, increased dietary concentration of lipase enzyme caused a linear reduction of feed intake and body weight gain (P < 0.01). At 21 d the percentage weight of the liver was significantly greater with 1.125% enzyme (P < 0.01). However, added enzyme had no effect on 21 to 42 d or 1 to 42 d growth or feed intake (P > 0.05) or on the size of any internal organs examined at 42 d. Pancreatic® enzyme has previously been shown to improve fat digestion and increase diet AMEn for young chicks fed animal-vegetable blended fats. These positive effects, however, are associated with marked anorexia, and from the present study, it seems that this effect was not related to physical changes in gut histology or in prolonged digesta transit time.

Effect of dietary enzyme on the metabolizable energy of diets with increasing levels of barley fed to broilers at different ages

The effect of enzyme addition on the AMen of a two-row barley for broiler chickens was determined with increasing levels of barley at 10 and 30 days of age in a 4 × 3 factorial design. Four levels of barley (30, 40, 50 and 60%) and two commercial enzyme complexes were used, the first obtained from Trichoderma reesei and Aspergillus niger and the second from Bacillus subtilis and Humícola insolens. At both 10 and 30 days of age, the AMEn of diets decreased significantly with increasing barley level (218 kJ for each 10% barley included). The enzyme response magnitude (1.4% on average) was affected by barley level; the response was only significant at 40 and 50% barley inclusion (AMEn improved 2.6% on average). There was no difference between enzyme complexes or ages in the AMEn of the diets or the barley (AMEn 12.71 and 13.10 MJ kg −1 for unsupplemented and enzyme supplemented barley respectively). Gut viscosity alone accounted for 97% of AMEn variation among unsupplemented diets. Increasing gut viscosity by 1 cps corresponded to a decrease in AMEn of 59 kJ. However, gut viscosity was not highly related to AMEn in enzyme supplemented diets because of the virtual complete elimination of the viscosity effect.