Nitrogen-corrected Apparent Metabolizable Energy Research Articles

Effects of Added Lipids on Digestibility and Nitrogen Balance in Oiled Common Murres ( Uria aalge ) and Western Grebes ( Aechmophorus occidentalis ) Fed Four Formulations of a Critical Care Diet.

Nutritional support is a primary therapy administered to oiled animals during responses to oil spills, but data informing nutritional decision-making during events are limited. In this study, 44 common murres ( Uria aalge ) and 6 Western grebes ( Aechmophorus occidentalis ), naturally oiled by oceanic seeps off the coast of Ventura and Santa Barbara Counties, CA, USA, were assigned to 1 of 4 groups fed diets with varying levels (6.8% [no added oil], 11%, and 20%) and types (salmon, corn) of oil added to a partially purified basal diet. Birds used in the study ranged from extremely emaciated to thin body condition (62%-80% wild bird mean body mass). Acid-insoluble ash was used as an indigestible dietary marker to quantify nitrogen retention, apparent nitrogen digestibility, nitrogen-corrected apparent metabolizable energy, energy digestibility, fat retention, fat digestibility, and estimated fat excretion. Fat excretion is important in these species because once birds have been cleaned they are at risk of plumage recontamination from excreted fat during care. Lower fat diets resulted in lower fat excretion but higher nitrogen retention, higher apparent nitrogen digestibility, and higher apparent metabolizable energy. Decreases in nitrogen retention were significantly related to increases in fat excretion. Regardless of diet, energy digestibility significantly declined with declines in body mass, suggesting severity of emaciation reduced a birds' ability to extract energy from food. Energy digestibility was highest in the 11% (low) salmon oil diet; hence, this diet had the highest effective energy content despite a lower gross kcal/kg diet. Diets fed during oil spills historically have had high fat concentrations to provide maximum caloric support. Results of this study suggest that lower fat diets may be more efficacious for nutritionally depleted seabirds. This study provides valuable data to guide clinical decision making regarding nutritional support during oil spills and other mass stranding events.

Productive performance, nutrient digestibility and intestinal morphometry in broiler chickens fed corn or wheat-based diets supplemented with bacterial- or fungal-originated xylanase

An experiment was conducted to evaluate effects of dietary supplementation of a corn- or a wheat-based diet with two sources of exogenous xylanase (fungal or bacterial originated) on productive performance, ileal nutrients digestibility, nitrogen-corrected apparent metabolisable energy (AMEn) and digestive organs morphometry in broiler chickens. Broilers were fed with one of the six dietary treatments consisting of two basal diets (based on corn or wheat) each with or without xylanase (from bacterial or fungal origin) supplementation. Compared with corn-based diet, feeding birds with the wheat-based diet improved weight gain and feed intake by 4.71 and 4.81%, respectively, and ileal digestibility of dry matter and crude protein were greater in birds fed wheat-based diets compared with the birds grown on corn-based during Days 1–21 of age (p<.05). Villus length and villus length to crypt depth ratio increased (p < .05) in birds received wheat-based diets compared with those fed on corn-based diets. Gizzard weight was greater in birds fed with corn-based diets on days 21 and 42 of age by 11.5% and 31.8%, respectively, compared with those received wheat-based diets (p < .05). Supplementing diets with fungal xylanase increased liver weight in birds grown on wheat-based diets compared with those grown on control and corn-based diets, respectively, on Days 21 and 42 of age (p < .05). It was concluded that supplementing a corn- or wheat-based diet with a xylanase of bacterial or fungal origin had no effect on productive performance or AMEn of diets in broiler chickens during the starter and growing periods.

Meal residual oil level and heat treatment after oil extraction affects the nutritive value of expeller pressed canola meal for broiler chickens

This experiment determined the effects of expeller-pressed canola meal (EPCM) residual oil (10% vs. 14%) and heat treatment at 115 °C for 25 min on the nitrogen-corrected apparent metabolizable energy (AMEn) value and amino acid (AA) digestibility for broilers. Day-old male chicks (six per cage) were fed six test diets (five cages per diet) from 14 to 21 d using the substitution method in a 2 × 2 factorial design. Increasing EPCM oil content from 10% to 14% increased (P < 0.05) EPCM AMEn value by 287 kcal kg−1. There was heat treatment by oil level interaction (P < 0.05) on standardized ileal digestibility of arginine, isoleucine, leucine, lysine, phenylalanine, threonine, and valine for EPCM in which heat treatment of the low oil EPCM reduced (P ≤ 0.0012) the digestibility of all these AA, but heat treatment of the high oil EPCM only reduced lysine digestibility. In conclusion, heat treatment of EPCM reduced its AMEn value and digestibility of some AA. The AA digestibility of EPCM with low oil was reduce...

Linear associations among phenological, morphological, productive, and energetic-nutritional traits in corn

Abstract: The objective of this work was to verify if there is linear dependence between the phenological, morphological, and productive traits and the energetic-nutritional ones in early maturing and super-early maturing corn genotypes. A total of 36 early maturing and 22 super-early maturing corn genotypes were evaluated in a randomized complete block design with three replicates, and the phenological, morphological, productive, and energetic-nutritional traits were measured. The matrix of phenotypic correlation coefficients among traits was determined; the multicollinearity diagnosis was carried out within each group of traits; and the canonical correlation analysis was performed. Linear dependence was observed between the groups of phenological, morphological, and productive traits and of the energetic-nutritional ones. In early maturing genotypes, significant canonical correlation shows the existence of linear dependence between the morphological and energetic-nutritional traits. The significant canonical pair shows that taller plants have lower amylose contents in the grains and reduced nitrogen-corrected apparent metabolizable energy. In super-early maturing genotypes, significant canonical correlations of the phenological, morphological, and productive traits with the energetic-nutritional ones indicate that a greater number of days from sowing to female flowering and ear insertion height, as well as a lower number of ears, increase ether extract contents in the grains.

Effect of soaking, fermentation with lactobacillus and enzyme treatment on nitrogen-corrected apparent metabolizable energy values of wheat in cockerels and quails.

An experiment was carried out to determine nitrogen-corrected apparent metabolizable energy (AMEn) values of processed wheat products with two levels of enzyme (0 and 0.5g/kg) and five processing methods [control (C), water-soaking for 12h (SO12h), 24h (SO24h) and 48h (SO48h) and fermentation with lactobacillus (FL)] in two species of poultry (cockerel and Japanese quail). In this study, each processing method group had six replications with two cockerels or four quails per replication. The results showed that the calculated AMEn values of processed wheat by different methods were as follows: C-12.61 and 12.60; SO12h-12.75 and 12.73; SO24h-12.80 and 12.79; SO48h-12.97 and 12.96; and FL-13.36 and 13.33 MJ/kg for cockerels and quails, respectively, indicating that fermentation improved AMEn values compared with the others. The mean AMEn of processed wheat with enzyme (13.12 MJ/kg) was significantly higher than that of processed wheat without enzyme (12.64 MJ/kg). However, there were no significant differences in the AMEn of processed wheat between cockerels and quails. The interaction between species and levels of enzyme in AMEn values was not significant. There was no significant difference (p>0.05) in three-way interactions among species, levels of enzyme and wheat processing methods for AMEn values. In conclusion, the results of the experiment suggest that the FL was more effective processing method of wheat to obtain high level of AMEn values than the others, and the combination of enzyme and processing methods can increase the AMEn values compared with processing methods alone.

Metabolizable energy and digestible amino acids of full-fat soybean without or with protease supplementation in diets for broilers

ABSTRACT Two experiments were carried out to determine the energy values and the true ileal digestibility of amino acids of nine toasted full-fat soybeans (FFSB), without or with the addition of monocomponent protease. In the first experiment, to determine the energy values, the method of excreta collection was used with 1120 broiler chicks at 14 days old, distributed in randomized blocks in a 10x2 factorial arrangement with nine full-fat soybeans (30% included) plus a control diet (70%) without or with the addition of protease, totaling 20 treatments with 8 replicates and 7 birds per cage. In the second experiment, 1120 broiler chickens from 24 to 28 days of age were distributed in randomized blocks in a 10x2 factor arrangement, with nine full-fat soybeans (40% included) + a protein free diet (60%), without or with the addition of protease, totaling 20 treatments with 8 replicates and 7 birds per cage. Ileal digesta collection was used to determine the true digestibility coefficients and the digestible amino acid content of full-fat soybean. The average values of nitrogen-corrected apparent metabolizable energy (AMEn) and their respective metabolization coefficients (CAMEn) were 3207 kcal/kg and 62.57%, respectively. The average values of digestibility coefficients of crude protein and essential and nonessential amino acids were 86.79, 87.90 and 84.34%, respectively. The inclusion of protease improved (P&lt;0.05) all evaluated parameters. Therefore, its use is recommended in diets containing full-fat soybeans for broiler chickens.

Enzyme Complex Added to Broiler Diets: Effects on Performance, Metabolizable Energy Content, and Nitrogen and Phosphorus Balance

Two trials were performed to evaluate the effects of an enzyme complex (EC) on broiler performance, metabolizable energy, and phosphorus and nitrogen balance. In the first trial, 960 one-day-old male Cobb broilers were randomly distributed in a 3 x 2 factorial arrangement (three nutritional levels and the inclusion or not of EC), totaling six treatments with eight replicates of 20 birds per pen, and reared until 42 days of age. The control diet was formulated to meet the broilers' nutritional requirements. The other diets contained reduced available phosphorus (P), metabolizable energy, and amino acid levels, considering 100% and 150% of the EC nutritional matrix. The inclusion of the EC (200 g/ton) resulted in better broiler performance, improving weight gain in 4% and feed conversion ratio in 3% (p< 0.05). In the second trial, 240 male broilers were randomly distributed into the same treatments with eight replicates of five birds per cage. The method of total excreta collection was used. There was an interaction (p< 0.05) between diets and EC for P intake, nitrogen (N) intake, and N retention. The EC supplementation improved nitrogen-corrected apparent metabolizable energy values in 2.02% (p< 0.05). Significant effects were observed on phosphorus and nitrogen balance (p< 0.05). Phosphorus retention improved in 10.26%, nitrogen retention increased in 5.3%, while nitrogen excretion decreased in 3.3%. Based on the results of the present study, we recommend the addition of 200 g/t of the enzyme complex to broiler diets, considering nutrient reduction based on 100% of the EC nutritional matrix.

Comparative performance of broiler chickens offered ten equivalent diets based on three grain sorghum varieties as determined by response surface mixture design

Ten nutritionally-equivalent diets containing 620g/kg grain sorghum, based on seven blends and three varieties (Block I, HP, Liberty), were offered to a total of 360 male Ross 308 chicks from 7 to 28days post-hatch. The effects of dietary treatments on growth performance, nutrient utilisation, starch and protein (Nitrogen) digestibility coefficients, disappearance rates and starch:protein disappearance rate ratios in the distal jejunum and distal ileum were determined. On the basis of response surface contour plots, the optimal weight gain of 1439g/bird would be generated by a 79.2-20.8 blend of HP and Liberty and the optimal feed conversion ratio (FCR) of 1.486 by a 55.6-44.4 HP-Liberty blend. Similarly, the optimal nitrogen-corrected apparent metabolisable energy (AMEn) of 12.38MJ would be generated by a 32.0-68.0 blend of HP and Liberty and the optimal apparent metabolisable energy to gross energy (AME:GE) ratio of 0.845 by a 31.1-68.9 HP-Liberty blend. Thus Block I sorghum was effectively rejected. Instructively, Block I contained higher concentrations of kafirin, phenolic compounds and phytate than the two other sorghum varieties. Across the ten diets, sorghum concentrations of these three factors were negatively correlated with AME:GE ratios or efficiency of energy utilisation. These negative linear regressions indicate that all three factors may be contributing to sub-standard starch/energy utilisation in broiler chicks offered sorghum-based diets.

Effects of derived meals from juncea (Brassicajuncea), yellow and black seeded canola (Brassicanapus) and multicarbohydrase enzymes supplementation on apparent metabolizable energy in broiler chickens.

Two experiments were conducted to determine the nitrogen-corrected apparent metabolizable energy (AMEn) of differently processed meals from Juncea (Brassica juncea), yellow and black seeded canola (Brassica napus), with or without supplementation of multi-carbohydrase enzymes (Enz) in diets for broiler chickens. The first experiment was a 3 × 2 × 2 factorial arrangement with the main factors being seed type (yellow [Yellow] or black [B1] canola seeds and Juncea seeds), processed at two temperatures (high temperature desolventized-toasted [HTDT] at 95°C or low temperature desolventized-toasted [LTDT] at 57°C), with or without Enz. In Exp. 1, a total of 384 one-day-old male broiler chicks were randomly assigned to 64 battery cages, with 6 birds/cage. The second experiment was a 2 × 2 × 2 factorial arrangement with the main factors being seed type (Yellow or black [B2]), seed source (Scott, Saskatchewan or Truro, Nova Scotia) and Enz (with or without) supplementation. A total of 264 one-day-old male broiler chicks were randomly assigned to 44 battery cages, with 6 birds per cage. In Exp. 1 and 2, all birds were fed a common starter diet from 1 to 14 days of age. From d 15 to 21, the birds were fed one of the test treatments, a basal grower diet or the basal grower diet replaced with 30% test ingredient with celite (0.8%) added as an inert marker. Excreta was collected on d 20 and 21. In Exp. 1, there were no interactions (P > 0.05) among seed type, processing temperature and Enz. Processing temperature and dietary Enz did not affect (P > 0.05) AMEn of different canola meals. The AMEn of prepress solvent extracted canola and juncea meals (PSEM) from Yellow (11.2 MJ/kg) was higher (P < 0.05) than B1 (10.2 MJ/kg) and Juncea (10.2 MJ/kg). In Exp. 2, there were no interactions (P > 0.05) among seed color, location and Enz. Supplementation of dietary Enz did not affect (P > 0.05) AMEn of different cold press canola meals. The AMEn of cold press canola meals (CPM) from Yellow (14.7 MJ/kg) was higher (P < 0.05) compared with B2 (12.2 MJ/kg). In conclusion, among the different processing methods of oil extraction, meals derived from yellow seeded canola had higher AMEn than B seeded canola and Juncea.

Influence of Palm Kernel Meal Inclusion and Exogenous Enzyme Supplementation on Growth Performance, Energy Utilization, and Nutrient Digestibility in Young Broilers.

The objective of the present study was to investigate the influence of palm kernel meal (PKM) inclusion and exogenous enzyme supplementation on growth performance, nitrogen-corrected apparent metabolizable energy (AMEn), coefficient of apparent ileal digestibility (CAID) and total tract retention of nutrients in young broilers fed corn-based diets. Four inclusion levels of PKM (no PKM [PKM0], 8% [PKM8], 16% [PKM16], and 24% [PKM24]) and two enzyme additions were evaluated in a 4×2 factorial arrangement of treatments. A total of 384, one-d-old male broilers (Ross 308) were individually weighed and allocated to 48 cages (eight broilers/cage), and cages were randomly assigned to eight dietary treatments. Results indicated that the inclusion of 8% and 16% PKM increased (p<0.05) the weight gain compared to the PKM0 diet. Birds fed the PKM8 diets had the highest (p<0.05) feed intake. Weight gain and feed intake were severely reduced (p<0.05) by feeding the PKM24 diet. Enzyme supplementation increased weight gain (p<0.05), independent of PKM inclusion level. In PKM0 and PKM8 diets, enzyme addition significantly (p<0.05) lowered feed conversion ratio (FCR); whereas enzyme addition had no effect on FCR of birds fed PKM16 and PKM24 diets. In PKM0 and PKM16 diets, enzyme addition significantly (p<0.05) increased CAID of nitrogen and energy but had no effect in the PKM8 and PKM24 diets. Inclusion of PKM into the basal diet, irrespective of inclusion level, enhanced (p<0.05) starch and fat digestibility. Inclusion of PKM at 16% and 24% resulted in similar CAID of neutral detergent fiber (NDF) but higher (p<0.05) than that of the PKM0 and PKM8 diets. Enzyme addition, regardless of the level of PKM inclusion, significantly (p<0.05) increased CAID of NDF. There was a significant (p<0.05) decrease in AMEn with PKM inclusion of 24%. The present data suggest that inclusion of PKM in broiler diets could be optimized if PKM-containing diets are formulated based on digestible amino acid contents and supplemented with exogenous enzymes. If amino acid digestibility and AME of PKM considered in the formulation, it can be included in broiler diets up to 16% with no deleterious effects on growth performance.

Influence of high dose of phytase and an emulsifier on performance, apparent metabolisable energy and nitrogen retention in broilers fed on diets containing soy oil or tallow

The effects of high dose of microbial phytase and an emulsifier on the performance, apparent metabolisable energy (AME) and nitrogen (N) retention in broilers fed on diets containing different fat sources were examined in a 5-week trial. Two fat sources (soy oil and tallow), two inclusion levels of E. coli phytase (500 or 1000 phytase units (FTU)/kg diet) and two inclusion levels of lysolecithin emulsifier (0 or 3.5 g/kg of diet) were evaluated in a 2 × 2 × 2 factorial arrangement of treatments.Throughout the 5-week trial, soy oil supplementation improved weight gain and feed per gain compared with tallow, but had no effect on feed intake.The high dose of phytase increased the weight gain and feed intake and lowered the feed per gain during d 1–21, but had no effect on performance parameters over the whole trial period.An effect of emulsifier was observed for feed intake during d 1–21 and over the whole trial period. Addition of emulsifier increased feed intake compared with diets without emulsifier.During weeks 1, 2, 3 and 5, birds fed on soy oil–based diets had higher nitrogen-corrected AME (AMEN) compared with those fed on tallow-based diets. During weeks 2, 3 and 5, the effect of phytase was significant for AMEN, with the high dose increasing the AMEN. During week 2, AMEN was increased with emulsifier addition.During weeks 1, 2, 3 and 5, birds fed on soy oil–based diets had higher fat retention compared with those fed on tallow-based diets. The high dose of phytase improved the retention of fat during week 5 and the addition of emulsifier resulted in higher fat retention during week 1.During weeks 2, 3 and 5, an interaction between fat source × phytase × emulsifier was observed for N retention. In soy oil–based diets, emulsifier plus 1000 FTU/kg phytase increased N retention compared with other groups, while in tallow-based diets, emulsifier addition increased N retention in diets with 500 FTU/kg, but not in 1000 FTU/kg diet.Overall, the present data suggest that the dietary fat source influenced performance, AMEN and fat retention in broiler chickens. There is opportunity to improve bird performance during d 1–21, AMEN and fat retention with higher doses of microbial phytase. Addition of the emulsifier increased the AMEN during week 2 and tract retention of fat during week 1, but this effect was not translated into improvements in performance.

Microbial phytase improves performance and bone traits in broilers fed diets based on soybean meal and containing lupin meal

A completely randomised design study with a 3 × 2 factorial arrangement was conducted. A total of 480 male broiler chickens were used to determine the influence of phytase addition, plant protein source [soybean meal, soybean meal + 200 g/kg of blue lupin meal (Lupinus angustifolius L.) or soybean meal + 200 g/kg yellow lupin meal (Lupinus luteus L.)] on performance of broiler chickens, ileal calcium (Ca), phosphorus (P) and protein digestibility, tibia bone characteristics and nitrogen-corrected apparent metabolisable energy. All diets were deficient in Ca, available P as well as lysine and total sulfur amino acids. Birds fed different protein sources were characterised by similar bodyweight gain and feed intake during the whole trial but feed conversion ratio was higher when birds were fed supplemented with yellow lupin meal (P &lt; 0.05). Phytase improved bodyweight gain and feed conversion ratio regardless of protein source (P &lt; 0.05). Diets supplemented with 200 g/kg blue or yellow lupin meal were found to be lower in nitrogen-corrected apparent metabolisable energy than soybean meal diets (P &lt; 0.05). Birds fed diets supplemented with phytase were characterised by higher utilisation of Ca and P than birds whose feed was not supplemented with phytase (P &lt; 0.05). Tibia bone ash as well as Ca content was similar across protein sources (P &gt; 0.05), whereas tibia P content was lower when soybean meal or blue lupin meal was used (P &lt; 0.05). Birds fed diets supplemented with blue lupin meal were characterised by the highest tibia P content (P &lt; 0.05). Birds fed phytase-supplemented diets were characterised by higher tibia Ca and P content irrespective of protein source.

Nutrient analysis, metabolisable energy and ileal amino acid digestibility of palm kernel meal for broilers

Nutrient composition, apparent metabolisable energy (AME) and ileal amino acid (AA) digestibility of palm kernel meal (PKM) were evaluated using laboratory analyses and animal studies. The AME assay was conducted with broilers using the classical total excreta collection between d 18 and 25 post-hatch. A maize-soy basal diet was formulated and a test diet, containing PKM, was developed by replacing (w/w) 250 g/kg of the basal diet with PKM. The AME of PKM was calculated based on the difference between the AME values of basal and test diets. Ileal AA digestibility of PKM was determined using two methods, namely direct and difference methods. In the direct method, the assay diet was formulated with the PKM serving as the sole source of AA. In the difference method, the basal and test diets used in the AME assay were used. All diets (both methods) contained titanium dioxide as an indigestible marker. The ratios between the titanium and AA in the diet and digesta were used to calculate the digestibility. The crude protein and fat contents of the PKM sample were 159 and 94.0 g/kg, respectively. The AME and nitrogen-corrected AME of PKM were determined to be 5.47 and 5.23 MJ/kg, respectively. The assay method had no effect (P > 0.05) on the ileal digestibility of protein, but influenced (P < 0.05–0.001) the digestibility of all AA except tyrosine (P > 0.05). Standardised ileal AA digestibility coefficients determined by the difference method were higher than those determined by the direct method. The present data showed that the use of direct method will underestimate the ileal AA digestibility coefficients of feedstuffs with low-protein content.

Validation of Prediction Equations of Energy Values of a Single Ingredient or Their Combinations in Male Broilers.

A set of prediction equations to estimate the nitrogen-corrected apparent metabolizable energy (AMEn) of individual ingredients and diets used in the poultry feed industry was evaluated. The AMEn values of three energy ingredients (maize, sorghum and defatted maize germ meal), four protein ingredients (soybean meal, maize gluten meal 60% crude protein, integral micronized soy and roasted whole soybean) and four diets (three containing four feedstuffs, complex diets, and one containing only corn-soybean meal, basal diet) were determined using a metabolism assay with male broilers from 1 to 7, 8 to 21, 22 to 35, and 36 to 42 days old. These values were compared to the AMEn values presented in the tables of energy composition or estimated by equation predictions based on chemical composition data of feedstuffs. In general, the equation predictions more precisely estimated the AMEn of feedstuffs when compared to the tables of energy composition. The equation AMEn (dry matter [DM] basis) = 4,164.187+51.006 ether extract (% in DM basis)–197.663 ash–35.689 crude fiber (% in DM basis)–20.593 neutral detergent fiber (% in DM basis) (R2 = 0.75) was the most applicable for the prediction of the energy values of feedstuffs and diets used in the poultry feed industry.

Effect of incorporating sugar beet pulp in the finisher diet on performance of geese

The aim of this work was to study the effects of incorporating sugar beet pulp (SBP) into the diet on the development of the crop and performance of geese. A total of 480 1-day-old ganders were divided into three groups differing in the composition and mode of distribution of the diet offered from day 56 to 89. The following two diets were used: a standard diet (nitrogen-corrected apparent metabolizable energy, AMEn 11.44 MJ/kg; 160 g/kg CP) or a diet containing 10% of SBP (SBP diet; AMEn 11.47 MJ/kg; 160 g/kg CP). The swelling capacity (SC) hydration was higher for SBP than for the standard diet (3.62 v. 2.72 ml of H2O/g of dry matter at 60 min; P<0.05). In the Control group, birds were fed with a controlled time of access to a standard diet. Other birds were fed the SBP diet with a controlled time of access (SBPt group) or a controlled quantity offered (SBPq). From day 90 to 104, 88 birds/group were overfed with a mixture containing mainly corn. Body traits including volume of the crop were measured at day 89. Fatty liver weight and commercial grading were measured at d 104. Feed intake from day 56 to 89 was higher in the Control group than in the SBPt group (8097 v. 7545 g; P<0.05), feed intake in the SBPq group being intermediate (7801 g); however, live weights (LW) of the birds were similar in the three groups measured at day 89 (5746 g; P>0.05). At day 89, the volume of the crop tended to be higher in the SBPt compared with the Control group (52.8 v. 48.8 ml/kg of LW; P=0.101). After overfeeding, feed intake (12 922 g), weight gain (2412 g), LW (8170 g), fatty liver weight (875 g) and commercial grading of the fatty liver were similar (P>0.1) for all the three groups. Therefore, SBP could help adapt the digestive tract of waterfowl to high feed intake through an increase in the crop volume, but its method of use – that is, level of incorporation and mode of distribution – should continue to be investigated.

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.

Digestibility and utilization of faba bean (Vicia faba L.) diets in broilers

There is a strong interest in maximizing the use of locally produced protein sources, like faba beans (FB), as a substitute for imported soybean meal (SBM). The aim of the present study was to determine the effects of dietary FB inclusion on diet digestibility. A further aim was to find an optimal inclusion level of locally produced unprocessed FB seeds in diets of broilers. A total of 196 male Ross 508 chicks were randomly assigned to four feeding treatments, and seven replications per treatment. FB seeds in proportions of 0, 80, 160, and 240 g/kg in the wheat- and SBM-based diets were tested in the grower period (bird age of 6–32 days). Digestibility and retention of nutrients were determined at the end of the experiment, and production performance was measured throughout the experiment. Apparent total tract digestibility of ash, nitrogen retention, apparent ileal digestibility of organic matter, and the nitrogen-corrected apparent metabolizable energy increased, with increased FB inclusion. The apparent ileal digestibilities of alanine, arginine, aspartic acid, histidine, and treonine increased by FB inclusion, while the apparent ileal digestibilities of cysteine and proline decreased. Digestibility differences were related to FB inclusion, but as well changes in proportion of wheat and SBM. Body weight, body weight gain, and feed consumption linearly decreased when dietary FB inclusion increased, while feed conversion ratio linearly improved. FB inclusion had no negative effect on the health of the broilers. In conclusion, 160 g/kg of FB can be used in broiler diets without major negative effects on production performance.

Effects of functional oils on coccidiosis and apparent metabolizable energy in broiler chickens.

The objective of the present study was to investigate the effects of a mixture of functional oils (Essential, Oligo Basics Agroind. Ltda) on performance response of chickens challenged with coccidiosis and the determination of apparent metabolizable energy (AME), nitrogen-corrected apparent metabolizable energy (AMEn), the coefficients of protein and ether extract digestibility and intestinal morphology of broilers fed with diets containing Essential. In Exp. 1, a completely randomized design (CRD) was used, with one control diet without Essential inclusion with coccidiosis (Eimeria acervulina, Eimeria maxima, and Eimeria tenella) challenged birds and two different inclusion rates of Essential (1.5 kg/ton and 2 kg/ton) with coccidiosis-challenged and non-challenged birds for each inclusion rate, using 10 replicates and 50 birds per experimental unit. After 7 d of coccidiosis challenge, the livability was approximately 10% lower (p<0.05) for the control group. Intestinal lesion scores were lower (p<0.05) in the anterior intestine and the cecum for the chickens supplemented. Feed efficiency and growth rate were improved in birds supplemented with Essential (p<0.05) before the coccidiosis challenge and during the first 7 d post infection. In Exp. 2, a CRD was used, with one control diet without Essential inclusion and one diet with inclusion of Essential (1.5 kg/ton), using nine replications and 33 chicks per pen. The diets with Essential yielded approximately 4% higher AME (p = 0.003) and AMEn (p = 0.001). Essential supplementation increased villus height in the jejunum on d 14 (p<0.05). Villus height:crypt depth ratio for the supplemented birds was larger (p<0.05) in the jejunum on d 7, larger (p<0.05) in the jejunum and ileum on d 14. In conclusion, these functional oils improved the energy utilization and the livability and decreased lesions caused by coccidiosis in supplemented birds.

Efficiency of microbial phytase supplementation in diets formulated with different calcium:phosphorus ratios, supplied to broilers from 22 to 33 days old

An experiment was conducted with broilers from 22 to 33 days of age to evaluate the efficiency of six microbial phytases supplemented in diets (1500 FTU/kg) that were formulated with three different calcium:available phosphorus (Ca:P(avail)) ratios (4.5:1.0, 6.0:1.0 and 7.5:1.0). A positive control diet without phytase was formulated with a Ca:P(avail) ratio of 7.5:3.4 to meet the nutritional requirements of the broilers. The P and ash contents of the tibia, magnesium in the plasma, performance, balance and retention of phytate phosphorus (P(phyt)), intake of total P and nitrogen (N), nitrogen-corrected apparent metabolizable energy and apparent digestibility of dry matter of the diets were not influenced (p > 0.05) by the type of phytase or the dietary Ca:P(avail) ratio. However, there was an interaction (p < 0.05) between the phytase type and the Ca:P(avail) ratio for the retention coefficients of total P, Ca and N. Phytase B resulted in the highest Ca deposition in the tibia (p < 0.01). Phytases D, E and F reduced the Ca concentrations in the tibia (p < 0.01) and plasma (p < 0.05). Phytase D increased the P level in the plasma and decreased the total P excretion (p < 0.01). Phytases E and F increased Ca excretion, while phytase A reduced it (p < 0.01). Regardless of the phytase type, increasing the dietary Ca:P(avail) ratio reduced (p < 0.05) the plasma P concentration and the excretion of total P and N and, conversely, increased (p < 0.05) the plasma concentration, intake and excretion of Ca. For the rearing period evaluated, it is possible to reduce the P(avail) of the diet to 1.0 g/kg when Ca is maintained at 7.5 g/kg, and the diet is supplemented with 1500 FTU of phytase A, C, D or E/kg. This diet allows the maintenance of performance and adequate bone mineralization, and it improves the Ca, total P and P(phyt) utilization in addition to reducing the excretion of N and P into the environment.

Variability of grain productivity and energy profile of maize (Zea mays L.) genotypes

The goal of the present work was to test if there is genetic variability between precocious and superprecocious cycle maize genotypes in terms of grain productivity and energy profile. Data from two separate experiments were used. An experiment was conducted with 36 precocious cycle genotypes and another experiment was conducted with 22 superprecocious cycle genotypes. The following variables were measured: grain productivity (PROD), ethereal extract (EE), starch (ST), amylose (AML), and nitrogen-corrected apparent metabolizable energy (AMEn). For all variables, basic statistics and analysis of variance was performed. For each experiment, the genotypic correlation matrix was calculated and the multicollinearity was evaluated. Then, the Mahalanobis generalized distance matrix was calculated, the clustering of the genotypes was performed and the averages of the groups formed were compared, separately for each experiment. There was genetic divergence between precocious genotypes, as well as between superprecocious genotypes, especially in terms of grain PROD, EE concentration, and AML concentration. Groups of more productive genotypes presented lower EE and higher AML grain concentrations. The results of the present study indicated that it is possible to plan crossings between groups of genotypes in terms of PROD, EE and AML, with the goal of maximizing heterosis.