Dietary Metabolizable Energy Research Articles

Dietary muramidase increases ileal amino acid digestibility of wheat and corn-based broiler diets without affecting endogenous amino acid losses

The objective of these studies was to evaluate the impact of dietary muramidase (MUR) on endogenous amino acids (AA) losses and digestibility of nutrients in wheat and corn-based broiler diets. In experiment 1, the effect of dietary MUR on the flow of endogenous AA (EAA) at the jejunum and terminal ileum of broilers were assessed using either the nitrogen (N) free diet method (NFD) or the highly digestible protein diet method (HDP; 100 g casein/kg diet). Sialic acid and muramic acid concentrations were measured in the jejunal content. In experiment 2, a 2x2x2 factorial arrangement of treatments with 2 base grains (wheat or corn), with low or high metabolizable energy (ME) levels, and without or with MUR supplementation was implemented. All diets contained phytase, xylanase, and cellulase. Apparent ileal digestibility (AID) of dry matter (DM), protein (CP), amino acids (AA), crude fat, and energy, as well as the apparent total tract metabolizability (ATTM) of DM, CP, and gross energy (GE) were determined. The standardized ileal digestibility (SID) of AA was obtained by correcting AID values for basal ileal EAA obtained from chicks fed with NFD or HDP in experiment 1, jejunal EAA flow of all AA was higher (P < 0.001) compared to the ileum, but this effect was method dependent. Jejunal, but not ileal, EAA flow measured with HDP was higher compared to NFD, as well as sialic acid (P < 0.001) and muramic acid (P < 0.004) concentrations. Muramidase inclusion had no effect on basal EAA flow, independently of the segment and the method used. In experiment 2, dietary MUR supplementation increased the AID of CP (P < 0.05), all AA, and tended (P=0.07) to increase the AID of GE, independently of the cereal type used. However, ATTM of DM and GE, but not CP, increased with MUR inclusion compared with the control treatments, especially in wheat and low ME diets (P < 0.05). In conclusion, MUR supplementation improved AID of CP and AA without affecting EAA losses and increases energy utilization.

Performance and behavior of piglets fed diets with different metabolizable energy levels

This study evaluated the effect of different metabolizable energy (ME) levels in diets on digestibility, performance, and feeding behavior of weaned piglets. A digestibility study to determine ME levels was performed using 12 male piglets with 11.5 ± 0.5 kg body weight (BW), in a cross-over design fed with different ME levels (treatments). In the performance study were used 64 female piglets with 7.5 ± 0.8 kg BW, in a randomized block design with four treatments (3.30, 3.40, 3.50, and 3.60 Mcal.kg-1ME levels), and feeding program with three phases (pre-initial I, pre-initial II, and initial). For feeding behavior, four pens of each treatment were monitored with cameras. The crude-protein digestibility coefficient reduced as dietary ME level increased (P &lt;0.05). In pre-initial I animal performance was not influenced (P &lt;0.05) by ME diet levels, and in the pre-initial II and initial phases, increases in ME caused quadratic (r² 0.99) and linear (r² 0.99) effects on daily feed intake, respectively. When ME levels increased, feed conversion ratio decreased linearly in the pre-initial II phase (r² =0.98), and quadratically in the initial phase (r²= 0.99). The number and duration of feeder visits linearly decreased as the diet energy levels increased (P &lt;0.05). Weaned piglets can regulate feed intake according to dietary ME levels. The performance of weaned piglets can be maintained using diets containing metabolizable energy levels between 3.30 at 3.60 Mcal.ME.kg-1 if the ratio of nutrients to energy is maintained constant.The feed intake behavior of weaned piglets is influenced by increases in dietary metabolizable energy levels evaluated, resulting in fewer and shorter visits to the feeder.

Dietary and phytogenic inclusion effects on the broiler chicken cecal ecosystem

Dietary modulation in broilers is crucial for the establishment of beneficial microbiota and, subsequently, the promotion of intestinal health. In this trial, a 2 × 2 factorial design was used with two different specifications with respect to dietary metabolizable energy (ME) and crude protein (CP) levels (i.e., 95% and 100% of recommendations) and phytogenic levels (0 and 150 mg/kg). Levels of total bacteria, Bacteroides spp., Lactobacillus spp., and Clostridium cluster XIVa attached to the cecal mucosa and in the cecal digesta were lower in broilers fed the 95% ME and CP specification diets, as was the molar ratio of butyric acid. In addition, the relative activity of autoinducers-2 (AI-2) and the expression levels of TLR4 and AvBD6 were increased. Phytogenic supplementation reduced cecal digesta levels of Escherichia coli and Clostridium cluster I levels, and increased Clostridium cluster IV levels. Moreover, the butyric acid molar ratio and the relative activity of AI-2 were increased, whereas the concentration of branched VFAs and the expression of AvBD6 and LEAP2 were reduced by phytogenic administration. Dietary specifications and phytogenic interactions were shown for the cecal-attached microbiota composition, metabolic activity of digesta microbiota, relative expression of autoinducers-2, and relative expression of toll-like signaling molecules and host antimicrobial peptides. In conclusion, it has been shown that ME and CP dietary specifications, combined or not with phytogenics, modulate multilevel gut biomarkers ranging from microbiota composition and metabolic activity to microbial communications and host signaling, inflammation, and defense.

Does modern broilers need less energy for better growth and intestinal development?

The current study was carried out to evaluate the response of broiler chicks to dietary energy. In total 11,400 day-old Ross-308 chicks (95 males and 95 females per pen) were placed in the study for 42 days. Hatchlings were randomly distributed to 6 dietary treatments with 10 replicates. Aviagen metabolisable energy (ME) recommendation for Ross 308 was served as a positive control (PC) and other treatments were adjusted to 101.25, 98.75, 97.50, 96.25 and 95% of PC. Birds had free access to water and pellet feed. Body weight (BW), Feed intake, feed conversion ratio (FCR), carcass yield and jejunal morphometric analysis were determined per replicate.Feeding the birds with 1.25% higher ME than PC did not result in any improvement in BW, FCR, mortalityand carcass parameters. Significant linear improvement was observed at starter period for BW and FCR with the reduction of dietary ME (p < 0.05). There was no significant impairment in final BW with the reduction of ME up to 5.0%. Whole period FCR reduced by 0.009, 0.022, 0.014, 0.037 points by lowering ME by 1.25, 2.5, 3.75and 5%, respectively (linear, p < 0.05). Carcass yield, abdominal fat and pancreas weights were not significantly influenced (p > 0.05). However, significant improvement in villus height, surface area (quadratic and cubic, p < 0.05), and villus width (quadratic, p < 0.05) were observed with 2.5 and 3.75% reduction of dietary ME. Dietary treatments had no significant effect on liver haemorrhagic lesion score.The results of the current research suggest that the optimum level of dietary energy level of modern broilers may be lower than the one recommended by the primary breeders. Lowering dietary energy density up to 5% leads to 0.03 points reduction in FCR without any negative effect on BW.

The effects of dietary essential fatty acid ratios and linoleic acid level in grow-finish pigs.

The objective of this study was to investigate the effects of dietary linoleic acid level and the ratio of linoleic acid:linolenic acid (LA:ALA) on the growth performance, expression of genes associated with lipid metabolism, and inflammatory status of grow-finish pigs. A total of 300 growing pigs (body weight [BW] = 41.1 ± 6.3 kg) were randomly assigned to either a high (30 g/kg; HLA) or low (15 g/kg; LLA) dietary linoleic acid level with a high (23:1; HR), moderate (13:1; MR) or low (4:1; LR) dietary LA:ALA in a 2 × 3 factorial design. Diets were fed across three 28-d phases and were balanced for dietary metabolizable energy. Pigs were housed five pigs per pen in single-sex pens. Blood samples were collected on days 0, 21, 42, and 84, and synovial fluid was collected from the hock joint on days 0 and 84 for inflammatory marker analysis. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4) with initial BW as a covariate, pen as the experimental unit, and LA level, LA:ALA, sex, phases, and their interactions as fixed effects. Compared to HLA, LLA pigs tended to have increased BW at days 56 and 84 (P = 0.088). There was no effect of LA × LA:ALA for growth performance. For the overall days 0 to 84 growth period, pigs fed HR had increased ADG compared to MR, with pigs receiving LR performing intermediate of MR and HR. Gilts receiving HR diets had increased day 84 BW compared to gilts receiving the low and moderate LA:ALA (P = 0.006), which was a result of improved overall days 0 to 84 ADG compared to gilts receiving the MR diets (P = 0.023). Barrows fed LR had improved BW on day 56 compared to MR and HR and higher final BW compared to HR, with MR performing intermediately (P = 0.006). This was a result of greater days 0 to 84 ADG (P = 0.023). Overall, C-reactive protein (CRP), tumor necrosis factor-α (TNFα), and interleukin-6 were reduced in the plasma of pigs over time (P ≤ 0.037). Across all treatments, CRP and TNFα were reduced in the hock and carpus synovial fluid on day 84 vs. day 0 (P ≤ 0.049). In conclusion, LA:ALA ratios utilized in this study can be fed at varying linoleic acid levels without impacting growth or inflammation. Additionally, LA:ALA ratios can differentially impact the growth of gilts and barrows.

The effects of dietary essential fatty acid ratios and energy level on growth performance, lipid metabolism, and inflammation in grow-finish pigs.

The objective of this study was to investigate the effects of dietary metabolizable energy (ME) level and the ratio of linoleic acid:α-linolenic acid (LA:ALA) on the growth performance, lipid metabolism, circulatory and joint inflammatory status, and synovial fluid proteome of grow-finish pigs. A total of 224 pigs (BW = 41.5 ± 6.1 kg; PIC Genus 337 × 1050, Hendersonville, TN) were randomly assigned to either a high (3.55 Mcal/kg; HE) or low (3.29 Mcal/kg; LE) ME dietary treatment with a high (23:1) or low (12:1) LA:ALA in a 2 × 2 factorial arrangement. Diets were fed across three 28-d phases. Pigs were housed either four barrows or four gilts per pen. Blood samples were collected on days 0, 21, 42, and 84. Synovial fluid was collected from the hock and carpus joints on days 0 and 84. Liver and adipose tissue samples were collected on day 84. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4) with pen as the experimental unit and energy level, essential fatty acid ratio, sex, phase, and their interactions as fixed effects. Compared to LE, HE increased days 28, 56, and 84 body weight (BW; P = 0.005). For the overall period, HE increased average daily gain (ADG) compared to LE (P < 0.001) and improved feed efficiency (P = 0.001), while LE increased feed intake compared to HE (P < 0.001). Gilts receiving diets with low LA:ALA had similar final BW to barrows receiving a low LA:ALA at days 28, 56, and 84 (P = 0.024), resulting from improved overall days 0-84 ADG compared to gilts receiving the high LA:ALA (P = 0.031). In the liver, HE decreased the mRNA abundance of acetyl CoA carboxylase (ACACA; P = 0.004), cluster of differentiation 36 (P = 0.034), and tended to decrease fatty acid synthase (FASN; P = 0.056). In adipose tissue, HE decreased ACACA (P = 0.001) and FASN (P = 0.017). Plasma inflammatory markers C-reactive protein (CRP) and tumor necrosis factor-α (TNFα) were reduced on day 84 compared to day 0 (P ≤ 0.014). In the hock and carpus synovial fluid, LE tended to reduce CRP and TNFα (P ≤ 0.096). Hock and carpus synovial fluid CRP were also reduced on day 84 compared to day 0 (P = 0.001). Age of the pig impacted serum and hock synovial fluid protein abundance, but not energy level, LA:ALA, or their interactions (P < 0.05). To conclude, the high and low LA:ALA ratios utilized in this study can be fed at varying energy levels without impacting growth. Additionally, LA:ALA ratios can differentially impact the growth of barrows and gilts.

Transition cow nutrition and management strategies of dairy herds in the northeastern United States: Part III—Associations of management and dietary factors with analytes, health, milk yield, and reproduction

The objective was to evaluate relationships between putative periparturient management and dietary factors at the pen and herd levels with metabolic- and inflammation-related analytes, health disorders, milk yield, and reproductive performance. Multiparous and primiparous cows from 72 farms in the northeastern United States were enrolled in a prospective cohort study. Farms were visited 3 times during the prepartum and postpartum periods: during the far-off dry, close-up dry, and fresh periods. Pen measurements were taken at each visit for the pens where cows sampled were housed, and particle size was determined for the total mixed ration for the pen. A survey was used to acquire data on herd-level management variables. Blood samples were collected from the same 11 to 24 cows per farm during the close-up and fresh period visits. Whole blood was analyzed for postpartum β-hydroxybutyrate (BHB) concentrations, and plasma was analyzed for prepartum and postpartum nonesterified fatty acids (NEFA) and postpartum haptoglobin (Hp) concentrations. Health event, milk yield, and reproductive records were acquired through the records management software program used on the farm. For the pen-level analysis, primiparous and multiparous cows were analyzed separately. For the pen- and herd-level analysis, a simple linear regression was conducted on all possible explanatory variables. Variables were included in the full multivariable general linear model if P < 0.20, and a manual backward stepwise elimination process ensued until all variables had P < 0.10. Our results indicate that pen- and herd-level management factors are associated with blood biomarkers, health, milk yield, and reproductive performance. For the prepartum period, our results support increasing the proportion of particles on the 19-mm sieve of the Penn State Particle Separator, optimizing bunk space, and not overfeeding metabolizable energy (ME), to decrease the prevalence of elevated postpartum NEFA, BHB, and Hp concentrations, decrease disorder incidence, maximize milk yield, and improve pregnancy risk to first service. For the fresh period, our results generally support optimizing bunk space, avoiding commingling, increasing feeding frequency, avoiding high physically effective undigested neutral detergent fiber (NDF) after 240 h of in vitro fermentation and high total fermentable carbohydrate diets while optimizing the inclusion of forage NDF, and ensuring adequate diet ME and metabolizable protein to reduce the prevalence of elevated postpartum NEFA, BHB, and Hp concentrations, minimize disorder incidence, maximize milk yield, and improve pregnancy risk to first service. At the herd level, our results generally support not vaccinating in the calving pen, minimizing the number of prepartum and postpartum pen moves, and avoiding long stays in the calving pen after parturition to reduce the prevalence of elevated biomarker concentrations, decrease disorder incidence, increase milk yield, and improve reproductive performance.

Dietary metabolizable energy and crude protein levels affect pectoral muscle composition and gut microbiota in native growing chickens

The experiment aimed to study effects of dietary metabolizable energy (ME) and crude protein (CP) levels alone and in interaction on performance, pectoral muscle composition and gut microbiota in native growing chickens. A total of 648 10-wks-old Beijing-You Chicken (BYC) female chickens were randomly allocated to 9 groups with 6 replicates per group and 12 chickens per replicate, and the chickens were fed with a 3×3 factorial diets (3 levels of dietary ME: 11.31 MJ/kg, 11.51 MJ/kg, 11.71 MJ/kg; and 3 levels of dietary CP: 14%, 15%, 16%). The results showed that dietary ME and CP levels didn't affect average feed intake (AFI), body weight gain, feed gain ratio (P > 0.05), but ME level significantly affected the AFI (P < 0.05); mortality rate of 11.31 MJ/kg group was the highest (P < 0.05). Dietary ME, CP levels, and the interaction significantly affected pectoral CP and crude fat (CF) content of the growing chickens (P < 0.01). Dietary CP level had opposite effects on pectoral CP and CF content (P < 0.01). The 16% CP increased the pectoral CF content, which may have a negative impact on meat flavor. Dietary ME level affected 11 types of pectoral free amino acids (FAA) contents, including aspartic acid, L-threonine (P < 0.05), also amino acid classification, for example, total amino acid (TAA) and essential amino acid (EAA) content (P < 0.05). The 11.51 MJ/kg group had the highest TAA, EAA, delicious amino acid (DAA) content and EAA percentage (P < 0.05), while 11.31 MJ/kg group had the lowest bitter amino acid (BAA) content and BAA percentage and the highest fresh and sweet amino acid (FSAA) percentage (P < 0.05). Dietary CP level significantly affected glutamine and tyrosine content (P < 0.05). The interaction of dietary ME and CP level affected C20:3n6 content, saturated fatty acid (SFA), and unsaturated fatty acid (UFA) percentage (P < 0.05). The CP level significantly affected SFA percentage (P < 0.05). The 16% CP level increased the diversity of gut microbiota, but at the same time increased the relative abundance of Proteobacteria (P < 0.05), which is a sign of microbiota disorder. The increase of dietary ME level resulted in a gradual decrease in the diversity and relative abundance of gut microbiota. In conclusion, the present study suggested that the medium dietary ME (11.51 MJ/kg) and low CP (14-15%) levels can be helpful for enhancing pectoral muscle composition, increase meat quality such as flavor and nutritional value, and benefit for gut microbiota in native growing chickens.

Evaluation of dietary metabolizable energy concentrations on meat quality and lipid metabolism-related gene expression in yellow-feathered chickens.

This study evaluated the effects of different dietary metabolizable energy (ME) concentrations on the meat quality, carcass traits, volatile flavourand lipid metabolism-related gene expression levels in yellow-feathered chickens. In total, 600 Huxu female chickens aged 90 days were randomly assigned to six dietary treatments, each with 10 replicates of 10 birds. During the finisher phase, the birds were fed diets containing 2880 (low), 2940, 3000, 3060, 3120and 3180 (high) kcal ME/kg. The results showed that the average daily gain of chickens increased as the dietary ME concentration increased, while the feed to gain improved (p < 0.05), and the intramuscular fat content of breast muscle increased (p < 0.05). The energy concentration had no effect on the breast muscle pH (45 min and 24 h), colour parameter (L*)or percentage of drip loss (p > 0.05), but the shear force values decreased significantly (p < 0.05). The diameter and area of the breast muscle fiber decreased and the muscle fibre density increased as the dietary ME concentration increased (p < 0.05). The highest ME concentration (3180 kcal) increased the percentages of aldehydes (hexanal, heptanal, 2,4-nonadienal, octanal, nonanaland 2-decenal), alcohols (2-nonen-1-ol, trans-2-undecen-1-ol, 7-hexadecenal, 2-hexyl-1-decanoaland n-nonadecanol-1,3,7,11-trimethyl-1-dodecanol), alkanes (2,6-dimethyl-heptadecane)and carboxylic acids (9-hexadecenoic acid), but reduced the percentages of octadecanal, octadecane, heneicosaneand tetradecanal (p < 0.05). In addition, the mRNA gene expression levels of fatty acid-binding protein 3 and apolipoprotein B were significantly upregulated in the liver, whereas that of cholesteryl ester transfer protein was significantly downregulated. In conclusion, increasing the ME diet to 3180 kcal/kg significantly improved the quality and flavour of the meat from yellow-feathered broilers. our finding may help poultry producers to improve the taste of meat by regulating genes related to lipid metabolism, thereby achieving the flavour and taste characteristics preferred by consumers.

Effect of the ratio of dietary metabolizable energy to nitrogen content on production performance, serum metabolites, rumen fermentation parameters, and bacterial diversity in yaks.

This study examined the effect of the ratio of dietary metabolizable energy (MJ) to nitrogen (g) content (ME:N) on average daily gain (ADG), blood biochemical indices, rumen fermentation parameters, and rumen bacterial community in yaks. Thirty-six male yaks, aged 2–3 years, were divided into three groups and received a ME:N ratio of 0.42 (HY), 0.36 (MY,) or 0.32 (LY) MJ/g. Dry matter intake ranged between 3.16 and 3.63 kg/d and was lesser (p < 0.001) in the LY group than the other two groups. ME intake increased (p < 0.001) with an increase in the ME:N ratio, while N intake did not differ among groups. The ADG was 660 g/day for the MY group, which was higher (p < 0.005) than the 430 g/day in the LY group, while the HY group gained 560 g/day and did not differ from the other two groups. Feed intake to ADG ratio ranged between 5.95 and 7.95, and numerically was highest in the LY group and lowest in the MY group. In general, the concentration of ruminal total volatile fatty acids (p < 0.03) and molar proportions of propionate (p < 0.04), increased, while the molar proportion of acetate (p < 0.005) and the acetate:propionate ratio decreased (p < 0.001) with a decrease in the ME:N ratio. The molar proportion of butyrate did not differ among groups (p = 0.112). Group MY had higher ruminal NH3-N content than group HY and had a higher serum glucose content but lower urea content, lactate dehydrogenase, and creatine kinase content than group LY. In ruminal bacteria at the phylum level, the relative abundance of Firmicutes (F) was greater and of Bacteroidetes (B) was lesser, while the F:B ratio was greater in group MY than in groups HY an LY. We concluded that the yaks consuming the diet containing a ME:N ratio of 0.36 MJ/g had the best performance of the three groups.

93 Predicting Metabolizable Energy from Digestible Energy for Growing and Finishing Beef Cattle and Relationships to Prediction of Methane

Abstract Reliable predictions of metabolizable energy (ME) from digestible energy (DE) are necessary to prescribe nutrient requirements of beef cattle accurately. Our objectives were to add new data to a previously published database and re-evaluate the relationship between DE and ME and to describe and evaluate new methane prediction equations derived from the DE:ME relationship. The previous database, which included 87 treatment means from 23 respiration calorimetry studies was updated to evaluate the efficiency of converting DE to ME by adding 47 treatment means from 11 additional studies. Diets were fed to growing-finishing cattle under individual feeding conditions. A citation-adjusted linear regression equation was developed where dietary ME concentration (Mcal/kg of dry matter [DM]) was the dependent variable and dietary DE concentration (Mcal/kg) was the independent variable: ME = 1.0001 × DE – 0.3926. The slope did not differ from unity; therefore, the intercept defines the value of ME predicted from DE. For practical use, we recommend ME = DE - 0.39. Based on the relationship between DE and ME, the citation-adjusted loss of methane was calculated and yielded a citation-adjusted value of 0.2433 Mcal/kg of DMI. Recognizing that methane production decreases per unit of intake energy as DMI increases above maintenance, we also examined the relationship between multiples of maintenance intake and daily energy lost as methane. This citation-adjusted relationship was: CH4, Mcal/kg = 0.3344 – 0.05639 × multiple of maintenance. Both the 0.2433 value and the result of the intake-adjusted equation can be multiplied by DMI to yield an estimate of methane production. Further research is needed to determine whether coefficients to predict methane from DMI could be developed for specific diet types, levels of DMI relative to body weight, or other variables that affect the emission of methane.

265 Effects of non-Starch Polysaccharide Degrading Enzymes + Lysophospholipids in Feeds with Varied ME Contents on Growth Performance and Nutrient Utilization of Pigs from 25 to 75 Kg BW

Abstract This study aimed to investigate efficacy of the combinational use of non-starch polysaccharide degrading enzymes (NSPase) and lysophospholipids (LPL) on growth performance and nutrient utilization in pigs fed feeds with varied metabolizable energy (ME) levels. Grower pigs (n = 270; 28.1 ± 0.6 kg BW) were allotted in a randomized complete block design with a 3 x 3 factorial arrangement of treatments fed for 51 d in 2 phases (30 and 21 d, respectively). Two factors were ME (3,260, 3,335, and 3,410 kcal/kg) and NSPase + LPL (ELPL at 0.00, 0.05, and 0.10%). Growth performance and backfat were measured. Blood was collected to measure plasma urea nitrogen (PUN) concentrations. Data were analyzed using the MIXED procedure on SAS 9.4. Increasing ME tended to increase (P = 0.066) ADG during Grower 2 and increased (P &amp;lt; 0.05) G/F during the overall period. Increasing ELPL supplementation increased (P &amp;lt; 0.05) both ADG and ADFI during Grower 2, whereas it tended to reduce (P = 0.084) G/F during the overall period. Supplemental effects of ELPL on increasing ADG was prominent (P &amp;lt; 0.05) at high ME content (3% above NRC requirement). Supplementation of ELPL tended to reduce (P = 0. 057) G/F during Grower 2 at low ME content (3% below NRC requirements). Backfat thickness and NEFA were not influenced by 2 factors. Increasing ME increased (P &amp;lt; 0.05) PUN during Grower 1 whereas increasing ELPL tended to increase (P = 0.077) PUN during Grower 2. In conclusion, supplementation of ELPL enhanced growth and feed intake of pigs from 50 to 75 kg BW, especially when dietary ME was above NRC requirement (3%) by fat supplementation (4%). These improvements may be due to increased nutrient utilization as indirectly indicated by increased PUN during fed status.

Effects of 25-hydroxycholecalciferol (25-OH-D3) and 1-hydroxycholecalciferol (1-OH-D3) on serum bone biomarkers and calcium and phosphorus balance and concentrations of energy in diets without or with microbial phytase fed to sows in late gestation.

The objective was to test the hypothesis that supplementation of diets for gestating sows with 25-hydroxycholecalciferol (25-OH-D3) or 1-hydroxycholecalciferol (1-OH-D3) affects serum biomarkers for bone and increases Ca and P balance and the apparent total tract digestibility (ATTD) of gross energy (GE), and the concentrations of digestible energy (DE) and metabolizable energy (ME) in diets without or with microbial phytase. Sixty multiparous sows were allotted to 1 of 6 diets. Diets were formulated using a 3 × 2 factorial with 3 inclusions of supplemental vitamin D metabolite (no metabolite, 25-OH-D3, or 1-OH-D3) and 2 inclusion levels of microbial phytase (0 or 1,000 units). Sows were housed individually in metabolism crates and feces and urine were collected quantitatively. Results indicated that there was no difference in the ATTD of dry matter (DM) and GE and concentration of DE among the 3 diets containing microbial phytase, but the ATTD of DM and GE and concentration of DE was greater (P < 0.05) in diets containing 1-OH-D3 compared with the diet without a vitamin D metabolite if phytase was not used (interaction; P < 0.05). In diets without microbial phytase, ME was greater in diets containing either one of the 2 vitamin D metabolites than in the diet without a vitamin D metabolite, but among diets with microbial phytase, the ME of the 1-OH-D3 diet was less than of the 25-OH-D3 diet (interaction; P < 0.05). No effect of microbial phytase on concentrations of DE and ME was observed. There was no interaction between supplementation of microbial phytase and vitamin D metabolites for Ca and P balances, and regardless of metabolite supplementation, use of microbial phytase increased (P < 0.05) the ATTD and retention of Ca and P. Regardless of dietary phytase, the ATTD and retention of Ca and P increased (P < 0.05) for sows fed a diet containing one of the vitamin D metabolites compared with sows fed the diet without a vitamin D metabolite. Serum biomarkers for bone resorption or bone tissue synthesis were not affected by experimental diets. In conclusion, the ATTD of DM and GE, concentrations of DE and ME, and Ca and P balance in phytase-free diets fed to sows in late gestation were increased by supplementation with 1-OH-D3 or 25-OH-D3, but no differences between the 2 vitamin D metabolites were observed. Supplementation of diets with microbial phytase increased Ca and P balance, but did not affect DE and ME of diets.

Effects of an emulsifier blend supplementation on growth performance, nutrient digestibility, intestinal morphology, and muscle fatty acid profile of broiler chickens fed with different levels of energy and protein

The effects of emulsifier blend (EB) supplementation of diets with various levels of metabolizable energy (ME) and crude protein (CP) on broiler performance, digestibility, gut morphology, and muscle fatty acid profile were investigated over a 42-d period. Diets were arranged factorially (2 × 2 × 3) and consisted of 2 levels of ME (normal [commercially recommended levels] and low [100 kcal/kg reduction in dietary ME]), 2 levels of CP and limiting amino acids (normal [commercially recommended levels] and low [95% of the normal CP level]), and 3 levels of EB supplementation (0, 1, and 2 g/kg of diet). A total of 1,200 one-day-old male broiler chickens (Ross 308) were randomly assigned to 12 treatment groups (5 pens/treatment with 20 birds/pen). Supplemental EB linearly improved (P < 0.05) final body weight, overall average daily gain, and feed conversion ratio, but the magnitude of the responses was greater in low-ME and low-CP treatments, resulting in significant ME × CP × EB interactions. Similarly, the inclusion of EB in the diet, particularly at 2 g/kg, increased the ileal digestibility of crude protein and crude fat, as well as the AMEn value (P < 0.05), but the response was greater at lower ME concentration, indicating significant ME × EB interactions. Additionally, there were CP × EB interactions (P < 0.05) for duodenal villus height and villus height/crypt depth ratio, indicating that the effect of EB on these responses was more marked at lower dietary CP levels. An increase in dietary EB levels was accompanied by a linear increase in the concentration of total saturated fatty acids and a linear decrease (P < 0.05) in the concentrations of total polyunsaturated fatty acids in both breast and thigh meat. In conclusion, the positive effects of EB supplementation, particularly at a dietary inclusion level of 2 g/kg, were clearly evident in broiler chickens fed with low nutrient diets (−100 Kcal/kg ME and/or −5% CP and limiting amino acids) in terms of growth performance, nutrient digestibility, and gut morphology.

Dietary metabolizable energy and crude protein levels affect the performance, egg quality and biochemical parameters of a dual-purpose chicken

Effects of dietary metabolizable energy (ME) and crude protein (CP) level on performance, egg quality and biochemical parameters were studied in a dual-purpose chicken-Beijing You Chicken (BYC) at peak laying period. A 3 × 3 factorial experiment was arranged, including 3 levels of dietary ME (11.31, 11.51, 11.71 MJ/kg) and 3 levels of dietary CP (14%, 15%, 16%). The results showed that dietary CP level alone and the interaction of ME by CP affected the total feed intake (TFI) during 27–30 wks, dietary ME level affected the mortality rate of 27–34 wks of age (p = 0.018), with the highest mortality rate found in 11.31 MJ/kg group (3.10%). The albumen height (AH), Haugh unit (HU) and egg grade (EG) of 16% group was higher than those in 14% and 15% groups (p < 0.05). Serum immunoglobulin G content in 11.31 MJ/kg group was lower than in 11.51 MJ/kg and 11.71 MJ/kg groups (p = 0.037). The present study suggested that dietary levels of 11.51 MJ/kg ME and 16.0% CP are enough to maintain the performance and egg quality of BYC at peak laying period. 11.31 MJ/kg ME increased the mortality of the chicken, which may be related to the decrease of the humoral immune function and antioxidative capability.

Letter to editors: misinterpretation of results led to a biased view about Guanidino acetic acid being beneficial in energy deficient diets

View responses to this article:Response to letter to the editors by Behnam Saremi referring to the article ‘Feeding guanidinoacetic acid to broiler chickens can compensate for low dietary metabolizable energy formulation’ by Pirgozliev et al

Effect of β-Mannanase Supplementation on Growth Performance, Ileal Digestibility, Carcass Traits, Intestinal Morphology, and Meat Quality in Broilers Fed Low-ME Diets.

Simple Summaryβ-mannans, an example of non-starch polysaccharides, is one of the important anti-nutritional factors found in many leguminous feedstuffs used as raw material in poultry feed formulation. β-mannans bind to nutrients, reduce their bioavailability, and also increase the viscosity of intestinal digesta, which prevents the proper mixing of enzymes with digesta and affects the digestibility of nutrients. All these conditions ultimately reduce the growth performance of poultry birds. So, the objective of present study was to lower the effect of β-mannans by using β-mannanase in broiler diets. Results suggested that β-mannanase supplementation improved the intestinal morphology, which helped to increase the dry matter and crude fiber digestibility in broilers fed low energy diets. In addition, growth performance of broilers was not affected by reducing dietary energy levels with added β-mannanase than the Control group. Similarly, carcass traits were not affected by decreasing dietary energy levels with supplementation of β-mannanase. In conclusion, it could be stated that a low caloric diet with added β-mannanase had no negative effect on growth performance and carcass characteristics; however, it improved the dry matter and crude fiber digestibility.Experiment was designed to analyze the effect of low caloric diets, supplemented with β-mannanase on growth performance, carcass characteristics, nutrient digestibility, and other parameters in broilers. In this study, 400 broiler chicks were randomly divided into four treatments (Cont: without β-mannanase; LM-30, MM-60, and HM-90: supplemented with 200, 400, and 600 mg/kg β-mannanase, respectively). Dietary metabolizable energy (ME) in Cont was standard (starter diet 3100 kcal/kg; finisher diet 3200 kcal/kg) and reduced by 30, 60, and 90 kcal/kg, correspondingly in β-mannanase-supplemented treatments. The results exhibited that growth performance was not affected by reducing dietary energy levels with supplementation of β-mannanase. Ileal digestibility of DM and CF was improved (p < 0.01) by supplementation of β-mannanase at low dietary ME levels. Concerning carcass traits, the relative weight of breast meat, drumstick, and abdominal fat increased (p < 0.05) with β-mannanase supplementation in low-ME diets. Treatment HM-90 showed significantly (p < 0.05) better results regarding villus height and VH:CD. It could be concluded from the present results that supplementation of β-mannanase could improve the nutrient digestibility so that it is possible to reduce the dietary energy level without compromising production performance, carcass trails, and meat quality in broilers.

An automatically progressed computer-controlled simulated digestion system to predict digestible and metabolizable energy of unconventional plant protein meals for growing pigs.

The objective of this experiment was to develop a new computer-controlled simulated digestion system to predict the digestible energy (DE) and metabolizable energy (ME) of unconventional plant protein meals for growing pigs. Nine meals tested included 1 source of rapeseed meal, 4 sources of cottonseed meal, 2 sources of sunflower meal, and 2 sources of peanut meal. Twenty growing pigs (Duroc × [Landrace × Large White]) with an initial body weight (BW) of 41.7 ± 2.6 kg were allotted to a replicated 10 × 3 incomplete Latin square design to determine the DE and ME of 1 basal diet and 9 experimental diets formulated with 9 unconventional plant protein meals. The DE and ME values of unconventional plant protein meals were calculated by the difference method. The in vitro digestible energy (IVDE) of 1 basal diet, 9 experimental diets, and 9 unconventional plant protein meals were determined with 5 replicates of each sample in a complete randomized arrangement. The IVDE/DE or IVDE/ME ranged from 0.96 to 0.98 or 1.00 to 1.01, and the correlation coefficient between IVDE and DE or ME was 0.97 or 0.98 in 10 experimental diets. Accordingly, the IVDE/DE or IVDE/ME ranged from 0.86 to 1.05 or 0.96 to 1.20, and the correlation coefficient between IVDE and DE or ME was 0.92 or 0.91 in 9 unconventional plant protein meals. The coefficient of variation (CV) of IVDE was less than that of DE and ME in the experimental diets (0.43%, 0.80%, and 0.97% for CV of IVDE, DE and ME, respectively) and unconventional plant protein meals (0.92%, 4.84%, and 6.33% for CV of IVDE, DE and ME, respectively). The regression equations to predict DE from IVDE in 10 experimental diets and 9 unconventional plant protein meals were DE = 0.8851 × IVDE +539 (R2 = 0.9411, residual standard deviation [RSD] = 23 kcal/kg DM, P < 0.01) and DE = 0.9880 × IVDE + 166 (R2 = 0.8428, RSD = 182 kcal/kg DM, P < 0.01), respectively. There was no statistical difference in the slopes (P = 0.82) or intercepts (P = 1.00) of these 2 equations. Thus, 10 diets and 9 unconventional plant protein meals were pooled to establish the regression equation of DE on IVDE as: DE = 0.9813 × IVDE +187 (R2 = 0.9120, RSD = 118 kcal/kg DM, P < 0.01). The regression equations to predict ME from IVDE in 10 experimental diets and 9 unconventional plant protein meals were ME = 0.9559 × IVDE +146 (R2 = 0.9697, RSD = 18 kcal/kg DM, P < 0.01) and ME = 0.9388 × IVDE + 3 (R2 = 0.8282, RSD = 182 kcal/kg DM, P < 0.01), respectively. There was no statistical difference in slopes (P = 0.97) but significant difference between the intercepts (P = 0.02) of these 2 equations. Our results indicate IVDE has similar response to the DE but different response to the ME in 10 experimental diets and 9 unconventional plant protein meals. Therefore, IVDE is more suitable to predict DE than ME of diets and unconventional plant protein meals for growing pigs.

Effect of Exogenous Enzymes Cocktail on Performance, Carcass Traits, Biochemical Metabolites, Intestinal Morphology, and Nutrient Digestibility of Broilers Fed Normal and Low-Energy Corn-Soybean Diets.

Simple SummaryCorn and soybean meal (SBM) are the principal sources of energy and protein in poultry feed, respectively. Decreasing feed cost per unit of production and increasing the nutritional value of feed ingredients like corn and SBM are continuous concerns for poultry producers. Corn and SBM-based diets are incompletely digested by poultry due to the presence of non-starch polysaccharides (NSPs), which can obstruct the processes of nutrient digestion and absorption. Poultry does not own endogenous enzymes capable of digesting NSPs. The use of enzyme cocktails (EC) and dietary energy sources are essential topics in the poultry industry because they could enhance nutrient utilization by reducing the harmful effects of NSPs. Therefore, evaluating the efficacy of EC that may improve the feeding value of corn–SBM diets warrants attention. The efficacy of two doses of an EC with multiple enzymatic activities at two levels of dietary metabolizable energy (ME) on the performance of broilers fed corn and SBM-based diets up to 35 days was evaluated. Our results indicate that adequately adjusting dietary ME and using the EC with xylanases, β-glucanases, cellulases, proteases, pectinases, and debranching enzymes activities could enhance the nitrogen-corrected apparent ME of corn and SBMbased diets for broiler chickens and potentially offer economic advantages to producers.Ross 308 broilers in a randomized complete block design with a 2 × 2 factorial treatment arrangement (four treatments with 12 replications of six chicks each) were fed corn and SBMbased diets with two concentrations of metabolizable energy (ME) (normal (positive control, PC) and low (negative control, NC)) and two amounts of enzyme cocktail (EC) (0% and 0.005%) for 35 days. Performance, carcass traits, serum metabolites, ileal histology, and apparent nutrient digestibility were evaluated. Compared with the non-supplemented diet, the use of EC improved feed conversion ratio (FCR) over 26–35 and 0–35 days (p < 0.01), European performance efficiency factor (EPEF) over 26–35 days (p < 0.05), dressing yield (p < 0.01), villus height (p < 0.05), nitrogen-corrected apparent ME (AMEn) (p < 0.01), and serum glucose (p < 0.05). Compared with the NC diet, feeding the PC diet improved FCR over all experimental periods (p < 0.01, p < 0.05, p < 0.05, and p < 0.01, respectively), EPEF over 0–10 days (p < 0.05), and AMEn retention (p < 0.01). To conclude, the AMEn of broilers fed corn and SBM diets could be improved by adequately adjusting dietary ME and using a cocktail of non-starch polysaccharide-degrading enzymes, improving commercial benefits to producers.

Requirements of Energy and Protein for Arabic Chicken Hens During Late Egg Production Period

The present study aimed to estimate the metabolizable energy (ME) and protein (CP) requirements of Arabic chicken hens during the late egg production period reared under a semi-scavenging system with free-choice feeding. A total of 112 sixty-two-week-old Arabic chicken hens were used. The treatments were control and the choice diet consisted of 6 replicate pens. Control hens received a control diet (2750 kcal of ME/kg and 14.1% of CP) complying with the Hy-line Brown Commercial Management Guide 2011, whereas the choice hens offered control and three other diets (high energy-high protein [3006 and 17.3], high energy-low protein [3089 and 12.7], and low energy-high protein [2656 and 17.0] kcal of ME/kg and % of CP, respectively). Feed, ME, and CP intake, the concentration of dietary ME and CP, and egg production were recorded weekly. Data were analyzed using Proc Mixed of SAS. The feeding method influenced feed intake, CP concentration, and ME concentration but had no significant effect on CP intake, ME intake, and egg production. Weekly feed intake of choice hens was lower than that of control hens (514.03 vs. 551.18 g /hen/week; P&lt;0.03). Dietary concentrations of ME and CP in the choice hens were higher than those in the control hens (2957 vs. 2750 kcal of ME/kg; P&lt;0.001 and 150.6 vs. 14.1 g of CP/kg; P&lt;0.001). Egg production of the choice hens was not significantly higher than that of the control hens (51.17% vs. 46.82%; P&gt;0.05). Feed intake, CP intake, and ME intake decreased significantly at week 66 onward, while egg production decreased at week 65 onward. It can be concluded that Arabic chicken hens in the late egg production period were able to adjust their energy and protein requirements by consuming more from high dietary energy than from a high dietary protein. Based on the choice feeding, ME and CP requirements for Arabic chicken hens during the late egg production period in the semi-scavenging system were 2957 kcal/kg and 151 g/kg and higher than ME and CP contain in the control diet of 2750 kcal/kg and 141 g/kg to maintain egg production. The egg mass and feed conversion ratio were better in the choice hens group.