Insoluble fibre and enzyme supplementation in mash or pellets diets on growth performance, apparent ileal digestibility and intestinal morphology of broiler chickens fed barley containing diets

BACKGROUND

Enzyme supplementation and the inclusion of fibre in the barley-based diets have been some of the alternatives proposed to improve productivity in the absence of growth promoters.

OBJECTIVE

This study was performed to investigate the effect of adding sunflower hulls (SFH), a multi-enzyme carbohydrate, and feed forms (mash and pellet) on performance and some physiological parameters in broiler chickens fed barley containing diets.

METHODS

Treatments were two feed forms (mash vs. pelleted), and four diets consisted of a barley-based diet (control, CTL) or test diets which contained either SFH at 30 g/kg, enzyme (ENZ; 0.2 g/kg) or combination of SFH and enzyme (SFH + ENZ).

RESULTS

The results showed that average daily feed intake and average daily gain were significantly increased in chickens that were fed ENZ (p < 0.05). The highest digestibility of ether extract (EE) was observed in the treatment containing SFH and SFH + ENZ (p < 0.05). The highest population of Lactobacillus spp. was observed in the treatment containing SFH (p < 0.05). The villus height and villus height to crypt depth ratios of duodenum and jejunum were significantly higher (p < 0.05) in broilers fed pellet diets compared to the mash.

CONCLUSION

It can be concluded that pellet diets reduce digesta viscosity and harmful microorganisms (Escherichia coli), increase growth performance, and improve intestinal morphology in barley-based diets. Moreover, SFH and ENZ had favourable effects on EE digestibility and caecal microbial population of broilers fed with barley containing diets.

Xylanase and beta-glucanase improve performance parameters and footpad dermatitis and modulate intestinal microbiota in broilers under an Eimeria challenge

Coccidiosis is an enteric disease of poultry worldwide that compromises gut health and growth performance. The current research investigated the effects of 2 doses of a multienzyme preparation on broilers' performance, gut health, and footpad dermatitis (FPD) under an Eimeria challenge. A total of 512 mixed-sex day-old chicks (Cobb 500) were randomly allocated to 4 treatments of 8 replicates. Treatments were: 1) nonchallenged control (NC); 2) NC + Eimeria challenge (CC); 3) CC + recommended level of xylanase and glucanase (XG, 100 g/t feed [on top]); 4) CC + double XG (2XG, 200 g/t feed). Eimeria spp. vaccine strains were gavaged on d 9 to induce coccidiosis in chickens. Performance parameters were evaluated during starter, grower, and finisher phases, and 4 birds per pen were euthanized on d 16 for sampling, FPD was scored on d 35, and litter moisture was analyzed on d 17 and 35. The data were analyzed using 1-way ANOVA with Tukey's test to separate means, and Kruskal-Wallis test was used for non-normally distributed parameters. The results showed that the Eimeria challenge was successful based on reduced weight gain and feed intake during grower phase, and higher FITC-d concentration, lesion score (female), and oocyst counts (d 14) in CC group compared to N.C. group, while XG and 2XG increased (P < 0.001) weight gain and improved FCR compared to CC and NC groups during finisher phase. The addition of X.G. and 2XG decreased litter moisture (P = 0.003) and FPD (P < 0.001) in challenged broilers compared to the N.C. group (d 35). Supplementing XG and 2XG reestablished the population of Lactobacillus in the cecum of challenged birds to an intermediate level between the NC and CC groups (P > 0.05). The inclusion of XG tended to increase the expression of Junctional adhesion molecule 2 (JAM2), which was not different from CC and NC groups (P > 0.05). In conclusion, the combination of xylanase and glucanase (Natugrain TS) improved the performance and modulated jejunal microbiota of broilers under mild Eimeria challenge.

Impacts of Solid-State Fermented Barley with Fibrolytic Exogenous Enzymes on Feed Utilization, and Antioxidant Status of Broiler Chickens

The present and future high demand of common cereals as corn and wheat encourage the development of feed processing technology that allows for the dietary inclusion of other cereals of low nutritional value in poultry feeding. Barley grains contain anti-nutritional factors that limit their dietary inclusion in the poultry industry. The treatment of barley with solid-state fermentation and exogenous enzymes (FBEs) provides a good alternative to common cereals. In this study, barley grains were subjected to solid-state microbial fermentation using Lactobacillus plantarum, Bacillus subtilis and exogenous fibrolytic enzymes. This study aimed to assess the impact of FBEs on growth, feed utilization efficiency, immune modulation, antioxidant status and the expression of intestinal barrier and nutrient transporter-related genes. One-day-old broiler chicks (Ross 308, n = 400) comprised four representative groups with ten replicates (10 chicks/replicate) and were fed corn-soybean meal basal diets with inclusions of FBEs at 0, 5, 10 and 15% for 38 days. Solid-state fermentation of barley grains with fibrolytic enzymes increased protein content, lowered crude fiber and reduced sugars compared to non-fermented barley gains. In consequence, the group fed FBEs10% had the superior feed utilization efficiency and body weight gain (increased by 4.7%) with higher levels of nutrient metabolizability, pancreatic digestive enzyme activities and low digesta viscosity. Notably, the group fed FBEs10% showed an increased villi height and a decreased crypt depth with a remarkable hyperactivity of duodenal glands. In addition, higher inclusion levels of FBEs boosted serum immune-related parameters and intestinal and breast muscle antioxidants status. Intestinal nutrient transporters encoding genes (GLUT-1, CAAT-1, LAT1 and PepT-1) and intestinal barriers encoding genes (MUC-2, JAM-2, occludin, claudins-1 and β-defensin 1) were upregulated with higher dietary FBEs levels. In conclusion, feeding on FBEs10% positively enhanced broiler chickens' performance, feed efficiency and antioxidant status, and boosted intestinal barrier nutrient transporters encoding genes.

Dry heating, moist heating, and microwave irradiation of cold-climate-adapted barley grain-Effects on ruminant-relevant carbohydrate and molecular structural spectral profiles

Different feed processing techniques affect barley digestibility and nutrient utilization in ruminants. To our knowledge, there are few studies on the interactive relationship between carbohydrate molecular structure profiles of cool-season-adapted barley grain and nutritional characteristics for ruminants. The objectives of this study were: (1) to investigate the effect of different technological processing methods on carbohydrate chemical profiles, Cornell Net Carbohydrate and Protein System-carbohydrate subfractions, ruminal and intestinal carbohydrate digestion of barley grain in dairy cows; (2) to study the effect of heat processing on carbohydrate molecular structure of barley grain using advanced molecular spectroscopy; and (3) to associate processing-induced changes in carbohydrate molecular structure with changes in carbohydrate metabolic profiles in dairy cows. Barley grain samples collected from Crop Research Field in Western Canada underwent four different processing treatments: control, dry heating (120°C for 60 min in an air-ventilated oven), moist heating (120°C for 60 min in an autoclave), and microwave irradiation (900 W and 2450 MHz for 5 min in a microwave). The heating conditions used in the current study induced some changes in rumen-degradable and -undegradable digestible fibre (CB3) fraction. Intestinally digestible CB3 was decreased after moist heating. Moist heating decreased starch digestibility compared to the other three treatments. The processing-induced carbohydrate molecular structure changes, which was revealed by advanced vibrational molecular spectroscopic technique (attenuated total reflectance-Fourier transform infrared), could be used to predict carbohydrate nutritional value.

Nutritional and Functional Roles of Phytase and Xylanase Enhancing the Intestinal Health and Growth of Nursery Pigs and Broiler Chickens

This review paper discussed the nutritional and functional roles of phytase and xylanase enhancing the intestinal and growth of nursery pigs and broiler chickens. There are different feed enzymes that are currently supplemented to feeds for nursery pigs and broiler chickens. Phytase and xylanase have been extensively studied showing consistent results especially related to enhancement of nutrient digestibility and growth performance of nursery pigs and broiler chickens. Findings from recent studies raise the hypothesis that phytase and xylanase could play functional roles beyond increasing nutrient digestibility, but also enhancing the intestinal health and positively modulating the intestinal microbiota of nursery pigs and broiler chickens. In conclusion, the supplementation of phytase and xylanase for nursery pigs and broiler chickens reaffirmed the benefits related to enhancement of nutrient digestibility and growth performance, whilst also playing functional roles benefiting the intestinal microbiota and reducing the intestinal oxidative damages. As a result, it could contribute to a reduction in the feed costs by allowing the use of a wider range of feedstuffs without compromising the optimal performance of the animals, as well as the environmental concerns associated with a poor hydrolysis of antinutritional factors present in the diets for swine and poultry.

Barley, an Undervalued Cereal for Poultry Diets: Limitations and Opportunities

Simple Summary

With the ever-increasing demand for poultry products, the continuous supply of conventional cereal grains such as maize has become a challenge. Barley has been recognised as a potential alternative feed ingredient that can replace common cereal grains in poultry diets. However, due to several limitations such as the presence of various anti-nutritive factors and the variability in nutrient composition and quality, the use of barley in poultry diets remains comparatively low. The previous findings on the optimum use of barley in poultry diets are also inconsistent primarily due to differences in research methodologies. The importance of using accurate nutrient profiles for specific barley cultivars to formulate barley-based diets is emphasised in this review. Moreover, the need to adapt feed processing conditions suitable to different barley cultivars to increase the inclusion of barley in poultry diets is highlighted in this review.

Abstract

The supply of conventional cereal grains, especially of maize, will be a significant constraint to the future growth of the poultry industry. Various alternative feed ingredients are being tested to replace maize in poultry diets. Barley (Hordeum vulgare L.) is one such feed ingredient, the use of which remains limited in poultry diets due to its low metabolisable energy, presence of anti-nutritive, soluble non-starch polysaccharides and consequent inter-cultivar variability. Differences in research methodologies used in published studies have also contributed to the inconsistent findings, preventing a good understanding of the nutritional value of barley for poultry. The importance of using accurate nutrient profiles, specifically metabolisable energy and digestible amino acids, for specific barley cultivars to formulate barley-based diets is emphasised. Nutritionists should also pay close attention to feed processing conditions tailored to the specific barley cultivars to increase the barley inclusion in poultry diets.

Enzyme complex addition in barley or rye broiler diets with two energy levels fed from 1 to 21 days

Two experiments were conducted to evaluate diet digestibility, performance, digestive parameters, and blood parameters when an enzyme complex (EC) was used in barley- and rye-based diets with different energy levels. In the digestibility assay (exp. I), 108 seventeen-day-old Cobb male broilers were distributed in a completely randomized design in 2 × 2 × 2 + 1 factorial arrangement with two feeds (barley or rye), two EC levels (0% and 0.02%), and two energy levels [3025 and 3125 kcal apparent metabolizable energy (AME)·kg−1], plus a control treatment. In exp. II, 1080 one-day-old Cobb male broilers were distributed in a completely randomized design in 2 × 2 × 2 + 1 factorial arrangement with two feeds (barley or rye), two EC levels (0% and 0.02%), and two energy levels (2875 and 2975 kcal AME·kg−1). No interactions were observed for any variables (exp. I and II). Enzyme complex improved the apparent metabolizable coefficient of gross energy (P = 0.0432) of diets. The EC provided greater weight gain (P = 0.0003) and better feed conversion (P = 0.0025). Intestinal viscosity at 21 d was reduced (P < 0.0001) with the addition of the EC. The EC improved nutrient digestibility and performance, but the effects of energy reduction on performance could not be overcome.

High steam-conditioning temperature during the pelleting process impairs growth performance and nutrient utilization in broiler starters fed barley-based diets, regardless of carbohydrase supplementation

The influence of supplemental carbohydrase (Carb) and conditioning temperature (CT) on growth performance, nutrient utilization and intestinal morphometry of broilers (d 1-21) fed barley-based diets was examined in a 2 × 3 factorial arrangement, evaluating 2 levels of Carb (0 and 150 g/tonne of feed) and three CT (60, 74, and 88°C). A total of 288, 1-day-old male broilers (8 birds/cage; 6 cages/treatment) were used. The activities of endo-1,4-β- glucanase, endo-1,3 (4)-β-glucanase and endo-1,4-β-xylanase in the Carb were 800 BGU/g, 700 BGU/g and 2,700 XU/g, respectively. On d 21, ileal digesta was collected for the determination of nutrient digestibility. There was no significant interaction between Carb and CT for any tested parameter. Supplemental Carb, regardless of CT, increased weight gain (WG; P < 0.05) and reduced feed per gain (F/G; P < 0.001) by 30 g/bird and 6.5 points, respectively. Increasing CT to 88°C reduced (P < 0.05) WG, but increased (P < 0.05) F/G compared to the diets conditioned at 60° and 74°C. Regardless of CT, Carb enhanced (P < 0.05) the digestibility of starch and AMEn by 1.15% and 32 kcal/kg, respectively. Compared to the diets conditioned at 60° and 74°C, CT at 88°C reduced (P < 0.05) digestibility of dry matter, nitrogen, phosphorus, gross energy, and AMEn. Birds fed diets conditioned at 88°C showed lower (P < 0.05) starch digestibility compared to those fed diets conditioned at 60°C. Conditioning at 88°C increased (P < 0.05) jejunal digesta viscosity by 10.2% compared to diets conditioned at 60° and 74°C. Overall, Carb supplementation improved WG, F/G, starch digestibility and AMEn in broilers fed barley-based diets, irrespective of CT applied. Conditioning barley-based diets at 88°C impaired the ability of birds to utilize nitrogen, starch, phosphorus and energy, and consequently deteriorated WG and F/G. The lack of significant interactions between Carb and CT indicated that negative impacts caused by high CT on bird performance and nutrient utilization occurred regardless of Carb enzyme supplementation. Supplemental Carb per se could not remedy the adverse effects of high CT.

Friend or Foe? Impacts of Dietary Xylans, Xylooligosaccharides, and Xylanases on Intestinal Health and Growth Performance of Monogastric Animals

This paper discusses the structural difference and role of xylan, procedures involved in the production of xylooligosaccharides (XOS), and their implementation into animal feeds. Xylan is non-starch polysaccharides that share a β-(1-4)-linked xylopyranose backbone as a common feature. Due to the myriad of residues that can be substituted on the polymers within the xylan family, more anti-nutritional factors are associated with certain types of xylan than others. XOS are sugar oligomers extracted from xylan-containing lignocellulosic materials, such as crop residues, wood, and herbaceous biomass, that possess prebiotic effects. XOS can also be produced in the intestine of monogastric animals to some extent when exogenous enzymes, such as xylanase, are added to the feed. Xylanase supplementation is a common practice within both swine and poultry production to reduce intestinal viscosity and improve digestive utilization of nutrients. The efficacy of xylanase supplementation varies widely due a number of factors, one of which being the presence of xylanase inhibitors present in common feedstuffs. The use of prebiotics in animal feeding is gaining popularity as producers look to accelerate growth rate, enhance intestinal health, and improve other production parameters in an attempt to provide a safe and sustainable food product. Available research on the impact of xylan, XOS, as well as xylanase on the growth and health of swine and poultry, is also summarized. The response to xylanase supplementation in swine and poultry feeds is highly variable and whether the benefits are a result of nutrient release from NSP, reduction in digesta viscosity, production of short chain xylooligosaccharides or a combination of these is still in question. XOS supplementation seems to benefit both swine and poultry at various stages of production, as well as varying levels of XOS purity and degree of polymerization; however, further research is needed to elucidate the ideal dosage, purity, and degree of polymerization needed to confer benefits on intestinal health and performance in each respective species.

Pre-starter feed thermally processed to feed broiler chicks

ABSTRACT The objective of this study was to evaluate the thermal processing of pre-initial diets on performance, morphometry of the organs of the digestive system and nutrient digestibility in broiler chicks. The test sample consisted of 180 broiler chicks distributed in a completely randomized design, with two treatments, six replications of 15 birds each. The treatments consisted of pelleted feed (70°C) and extruded feed (150°C). The metabolism test was realized from 4 to 7 days of age, while the performance and morphometry of the organs of the digestive system were evaluated at 7 and 21 days of age. The data were submitted to analysis of variance. At seven days of age, chicks that consumed extruded feed had lower feed intake, less development of digestive tract organs, lower nitrogen absorption rate, dry matter, in addition to less metabolizable energy compared to pelleted feed. Likewise, at 21 days of age, chicks that consumed extruded pre-starter feed performed worse than pelleted feed. The conclusion is thus reached that feed extruded at 150 ° C for broiler chicks in the pre-initial phase, results in lower nutrient digestibility and an inferior development of the organs of the digestive system at 7 days of age and worse performance at 21 days.

Effect of particle size of insoluble fibre on growth performance, apparent ileal digestibility and caecal microbial population in broiler chickens fed barley-containing diets

1. This study was conducted to investigate the effect of particle size of insoluble fibre on growth performance, apparent ileal digestibility (AID) and caecal microbial population in broiler chickens fed barley-containing diets. 2. The dietary treatments included: a barley-based diet (control, CTL) or test diets which contained high-fibre ingredients, either sunflower hulls (SFH), sugarcane bagasse (SB) or wheat bran (WB) ground through a 1.0 (fine) or 3.0 mm (coarse) screen that were added to the control diet at 30 g/kg. 3. For the entire experimental period, insoluble fibre inclusion improved ADG (P < 0.05) and FCR (P < 0.05) compared to the CTL group. Broilers fed SFH had higher (P < 0.05) ADG and better (P < 0.05) FCR than broilers fed SB. 4. Fibre inclusion increased the relative weight of breast and thigh and decreased relative weight of liver compared to the CTL group, but coarse grinding of the SB decreased relative weight of abdominal fat (P < 0.05). 5. The digestibility of nutrients increased with dietary inclusion of insoluble fibre compared to the CTL group. Coarse grinding of SFH increased AID of crude protein compared to the coarse grinding of WB or SB. Fine grinding of various types of fibre improved the AID of fat (as ether extract) and organic matter (P < 0.05). 6. Fine grinding of the WB decreased caecal populations of E. coli. The inclusion of SFH increased caecal populations of Lactobacillus spp. (P < 0.05). Coarse grinding of various types of fibre decreased the caecal population of coliforms (P < 0.05). 7. The inclusion of WB increased digesta viscosity in the ileum compared to samples from the SB and SFH groups (P < 0.05). Coarse grinding of various types of fibre decreased the digesta viscosity in the ileum (P < 0.05). 8. Overall, the data showed that dietary inclusion of insoluble fibre improved growth performance, increased AID of nutrients and decreased ileal viscosity in the birds fed diets containing barley.

Influence of grinding size of the main cereal of the diet on egg production and eggs quality of brown egg laying hens from 33 to 65 weeks of age

The influence of grinding size of the main cereal of the diet on production and egg quality traits was studied in brown hens from 33 to 65 wk of age. The experiment was completely randomized with 6 treatments arranged as a 3 × 2 factorial with 3 main cereals (barley, corn, and wheat) and 2 grinding size of the cereal (6 and 10 mm screen). Each treatment was replicated 11 times (10 hens/replicate). Diets were isonutritive and contained 2,740 kcal/kg AMEn and 16.8% CP. Egg production, ADFI, egg weight, and feed conversion ratio (FCR) were determined by period (4 wk) and for the entire experiment. Egg quality traits (percentage of undergrades, Haugh units, thickness, strength, color of the shell, and proportion of albumen, yolk, and shell) were measured also by period. No interactions between main cereal and grinding size of the main cereal of the diet were observed for any of the traits studied. Feed intake, egg production, and BW gain were not affected by diet or grinding size. Eggs were heavier (P < 0.01) in hens fed barley than in hens fed corn or wheat, probably because of the higher fat content of the barley diets. Also, FCR tended to improve in hens fed barley compared with hens fed corn or wheat (P = 0.07). Diet did not affect any of the egg quality traits studied. In summary, barley and wheat conveniently supplemented with enzymes, can be used in substitution of corn at levels of up to 55% in diets for laying hens, without any adverse effect on egg production or egg quality traits. Moreover, the substitution of corn by a combination of barley and supplemental fat increased egg size. Consequently, the inclusion of one or other cereal in the diet will depend primarily on their relative cost. Within the range studied, screen size (6 vs. 10 mm) of the cereal had limited effects on hen production.

Nitrogen-corrected apparent metabolizable energy values of barley varies by treatment and species

The aim of this study was to evaluate the effects of two species of poultry (cockerel and Japanese quail), two levels of enzyme (0 and 0.5 g/kg), and 6 processing methods (control (C), gamma irradiation 25 (GI25), and 50 kGy (GI50), autoclaving (AU), fermentation without lactobacillus (F), and fermentation with lactobacillus (FL)) on the nitrogen-corrected apparent metabolizable energy (AMEn) of barley. In this experiment, each processing method was tested at two levels of enzyme (0 and 0.5 g/kg) in six replications with two cockerels or four quails per replication. The results showed that the AMEn values by barley processing methods were: C-11.45 and 12.27; GI25-11.50 and 11.30; GI50-11.49 and 11.29; AU-11.70 and 11.46; F-12.90 and 12.30; FL-1295 and 12.51 MJ/kg in cockerels and quails, respectively. The AMEn (11.49 MJ/kg) of enzyme 0 was significantly lower than that of enzyme 0.5 (12.35 MJ/kg). There was a significant difference in the AMEn of processed barley between cockerels and quails. In conclusion, the most effective processing method of barley for AMEn is fermentation with lactobacillus and enzyme.

Influence of dietary rapeseed meal levels on growth performance, organ health and standardized ileal amino acid digestibility in meat ducks from 15 to 35 days of age

This study was conducted to investigate the effects of dietary rapeseed meal (RSM) inclusion levels on growth performance, organ health and standardized ileal amino acid digestibility (SIAAD) in meat ducks from 15 to 35 days of age. Six hundred and eighty 15-days-old ducks were randomly allotted to five treatments based on body weight. Five isonitrogenous and isoenergetic diets were formulated on a digestible amino acid basis by replacing 0% (the control), 25%, 50%, 75% and 100% (based on fresh) of protein from soya bean meal (SBM) with protein from RSM. The corresponding levels of RSM in experimental diets were 0%, 6.66%, 13.32%, 19.98% and 26.64% respectively. With increasing dietary RSM levels, body weight (BW) and average daily gain (ADG) linearly decreased (p < 0.001), whereas feed-to-gain ratio (F: G) linearly increased (p = 0.0078). Ducks fed the diets with 13.32% or more RSM had significantly lower (p < 0.05) BW, ADG and ADFI, or higher F: G than ducks fed the control diet. The maximum limit of dietary RSM supplementation was estimated to range from 4.27% to maximize ADG for 15 to 35 days to 11.69% to maintain feed intake for 15 to 35 days on the basis of a broken-line model. At day35, the 4th primary wing feather length and SIAAD (except for Met, Thr and Val) linearly decreased (p < 0.001), and the thyroid glands weight (% of BW) linearly increased (p < 0.05) with increasing dietary RSM levels. Ducks fed the RSM inclusion diets had significantly lower (p < 0.0001) serum aspartate aminotransferase (AST) and alanine transaminase (ALT) activities than ducks fed the control diet. These results suggested that the maximum limit of dietary RSM containing 7.57 μmol/g glucosinolates was estimated to be 4.27% to avoid growth reduction.

Effects of fiber inclusion on growth performance and nutrient digestibility of piglets reared under optimal or poor hygienic conditions

Two experiments were conducted to study the effects of inclusion of additional fiber in the Phase I diet on growth performance and nutrient digestibility in piglets reared under "optimal" or "poor" hygienic conditions. In both experiments, the design was completely randomized with a control diet that contained 2.2% crude fiber and 8 additional isonutritive diets that included 2.5 or 5.0% of sugar beet pulp (SBP), straw, oat hulls (OH), or wheat middlings (WHM). Preplanned polynomial contrasts were used to study the effects of 1) fiber inclusion (control diet vs. average of the 8 fiber-containing diets), 2) source of fiber, 3) level of fiber, and 4) interaction between source and level of fiber. In Exp. 1 (clean barn), fiber inclusion increased ( < 0.01) the incidence of postweaning diarrhea (PWD) and reduced ( < 0.05) feed efficiency and apparent total tract digestibility (ATTD) of all nutrients except that of CP, which was not affected. Piglet performance was not affected by source or level of dietary fiber. The ATTD of all nutrients decreased ( < 0.05) as the level of fiber increased and was lower in pigs fed straw or OH than in pigs fed SBP or WHM. The apparent ileal digestibility of GE and DM decreased ( < 0.05) with fiber inclusion, a reduction that was more pronounced ( < 0.05) with straw or SBP than with OH inclusion, with WHM inclusion being intermediate. Fiber inclusion did not affect villous height to crypt depth ratio of the ileum mucosa. The inclusion of 5% of a fiber source increased and counts in the cecum ( < 0.001) but the to ratio was not affected. In Exp. 2 (dirty barn), fiber inclusion did not affect piglet performance but tended to increase PWD ( = 0.07). Also, fiber inclusion reduced ( < 0.05) the ATTD of all dietary components except that of CP, which was not affected. Source and level of fiber did not affect ATTD of nutrients except for DM, which was greater for pigs fed SBP than for pigs fed straw ( < 0.05). In conclusion, in the current research, pigs reared under optimal hygienic conditions had lower incidence of PWD, better growth performance, and greater DM and GE digestibility than pigs reared under poor hygienic conditions. An excess of dietary fiber was more detrimental for all these traits in piglets reared under optimal hygienic conditions. The effects of the source and level of fiber on piglet performance was limited in the 2 experiments.

Inclusion of insoluble fiber sources in mash or pellet diets for young broilers. 1. Effects on growth performance and water intake

The effects of feed form and the inclusion of insoluble fiber in the diet on growth performance and water intake were studied in female broilers from 0 to 21 d of age. The experimental design was completely randomized with 14 treatments arranged as a 2 × 7 factorial with 2 feed forms (mash vs. pelleted) and 7 diets that consisted of a control diet low in fiber (1.6% crude fiber) based on broken rice, fermented soybean meal, and fish meal and 6 extra diets that resulted from the inclusion of 3 insoluble fiber sources (oat hulls; OH, rice hulls; RH, and sunflower hulls; SFH) at 2 levels (2.5 vs. 5%). Each treatment was replicated 6 times. Broilers fed pellets had 32% greater ADG and 3% better feed to gain ratio (F:G) than those fed mash (P ≤ 0.001). The inclusion of the fiber sources improved ADG (P ≤ 0.05) and F:G (P ≤ 0.05). Pelleting increased (P ≤ 0.001) water intake from 6 to 8 d, water-to-feed intake ratio from 18 to 20 d, and moisture content of the excreta at 20 d of age. The inclusion of the insoluble fiber sources increased water intake (P ≤ 0.05) from d 18 to 20 but not from d 6 to 8. Increasing the level of fiber inclusion from 2.5 to 5.0% tended to increase (P = 0.086) moisture content in the excreta at d 20. Pelleting and the inclusion of insoluble fiber sources improved ADG and F:G in broilers fed low-fiber diets, and the improvements observed were more pronounced with pellets than with mash. Growth performance of young broilers improves with the addition of moderate amounts of structural insoluble fiber in the diet, regardless of feed form. The inclusion of OH or SFH into low fiber diets was more beneficial for improving broiler performance than the inclusion of RH.

Influence of the main cereal and feed form of the rearing phase diets on performance, digestive tract, and body traits of brown-egg laying pullets from hatch to 17 weeks of age

The effects of the main cereal and feed form of the rearing phase diets on growth performance, gastrointestinal tract characteristics, and body traits were studied in brown-egg pullets from hatch to 17 wk of age. Eight dietary treatments that were a combination of 2 main cereals (corn vs. wheat) and 4 feeding programs were used. The feeding program consisted in feeding crumbles from 0 to 5, 0 to 10, or 0 to 17 wk of age followed by mash until 17 wk, or feeding mash continuously from 0 to 17 wk. Each treatment was replicated 9 times. From hatch to 17 wk of age, pullets fed corn had similar ADG but poorer feed conversion ratio (FCR; P < 0.001) than pullets fed wheat. Also, pullets fed crumbles continuously (0 to 17 wk) had greater ADG (12.3 vs. 11.5 g; P < 0.001) and better FCR (4.21 vs. 4.36; P < 0.001) than pullets feed mash continuously, with pullets that were changed at any age of the rearing period from crumbles to mash feeding showing intermediate results. At 17 wk of age, the relative weights (% BW) of the gastrointestinal tract and gizzard were greater in pullets fed corn than in pullets fed wheat (P < 0.01) but the relative length (cm/kg full BW) of the small intestine, body, and tarsus was not affected. Pullets fed crumbles continuously had lighter gizzards (P < 0.001), higher gizzard pH (P < 0.001), and were shorter (P < 0.01) than pullets fed mash continuously, with pullets fed the other 2 treatments being intermediate. In summary, wheat can be used in substitution of corn in pullet diets without any adverse effect on growth performance. Feeding crumbles improves pullet performance but hinders gizzard and gastrointestinal tract development. Growth performance, gastrointestinal tract, and body traits of the pullets re-adapt quickly to changes in feed form of the rearing diets.

Standardized ileal amino acid digestibility of expeller-extracted canola meal subjected to different processing conditions for starter and grower broiler chickens

Six expeller-extracted canola meal (ECM) samples produced under different seed conditioning temperatures (90, 95, or 100°C) and screw torques in the second press (low or high) were evaluated in a 3 × 2 factorial arrangement of treatments to determine the effect of processing on standardized ileal amino acid digestibility (SID) in 10 and 24-day-old broilers. A nitrogen-free diet was fed to determine ileal endogenous amino acid flow. Each diet was fed for 5 d to 6 replicate cages of 10 or 7 chicks, and ileal samples were collected at 10 and 24 d, respectively. The endogenous flow (mg/kg DM intake) of CP and all amino acids except Cys decreased (P < 0.01) with age. Conditioning temperature by screw torque interactions were detected (P < 0.05) for apparent ileal digestibility (AID) of CP, Arg, Ile, Lys, Phe, Thr, Ala, Asp, Glu, Pro ,and Ser at d 10, and the same trend was observed at d 24 except for Ile, Phe, Ala, and Pro (P > 0.05). Meals processed under medium conditioning temperature (95°C) at either low or high screw torque had the greatest (P < 0.05) AID of CP and total amino acids. The SID values followed a similar pattern as AID at both ages. When corrected for endogenous losses, the average AID of total amino acids improved approximately 3.5 and 2.0 units, at 10 and 24 d, respectively. The AID and SID values increased (P < 0.05) with age for most AA, but the effect of age was not consistent between ECMs. A negative correlation was detected between NDF and neutral detergent-insoluble nitrogen (NDIN) content of the meals and SID values of Lys at d 24 (r = -0.79, r = -0.76; P = 0.001, respectively). Processing conditions affected CP and amino acid digestibility, likely because of alterations to the chemical composition of ECM and formation of indigestible complexes of amino acids with fiber. The AID and SID values increased with age independent of meal processing conditions.

Effect of dietary supplementation of xylanase on apparent ileal digestibility of nutrients, viscosity of digesta, and intestinal morphology of growing pigs fed corn and soybean meal based diet

This study was to determine apparent ileal digestibility of acid detergent fiber (ADF), neutral detergent fiber (NDF), dry matter (DM), energy, organic matter (OM), crude ash, digesta viscosity, and gut morphology in nursery pigs fed diets containing xylanase (Lohmann Animal Nutrition GmbH, Cuxhaven, Germany). The diet (61% corn, 35% soybean meal, 1% poultry fat, and 3% minerals and vitamins) was mixed with 3 levels of xylanase (0, 700, and 1400 LXU/kg). Thirty-six barrows (17.6 ± 3.3 kg) received one of 3 treatment diets based on a randomized complete block design with the initial body weight (BW) as a block. Pigs were individually housed and received experimental diets twice daily (0700 and 1700 h) at a fixed amount based on BW of pigs (0.09 × BW^0.75 kg). Pigs were fed diets for 10 d, and chromium oxide (0.3%) was added to the diets from d 6 as an indigestible external marker. Pigs were euthanized at the end of d 10 for the collection of digesta and tissues. Jejunal digesta were centrifuged to measure viscosity using a viscometer (Brookfield Engineering Laboratories, Stoughton, MA). Diets and freeze-dried ileal digesta were used to measure ADF, NDF, and chromium to calculate apparent ileal digestibility of ADF and NDF. Villus height and crypt depth of jejunum were measured using a microscope (Fisher Scientific, Hampton, NH). Data were analyzed using polynomial contrasts in the MIXED procedure of SAS version 9.3 (SAS Inc., Cary, NC, USA). Morphological measurements and ileal ADF digestibility were not affected by increasing xylanase. However, increasing xylanase supplementation from 0 to 1400 LXU/kg enhanced ileal digestibility of NDF (P < 0.042, linear) from 27.9 to 40.3%, DM (P < 0.006, linear) from 55.4 to 64.6%, OM (P < 0.006, linear) from 59.2 to 67.7%, and energy (P < 0.003, linear) from 58.8 to 68.0%. Viscosity of jejunal digesta decreased (P < 0.023) in a non-linear manner from 2.9 to 2.5 centipoises (cP). In conclusion, the usage of xylanase in corn and soybean meal based pig diets linearly enhanced digestibility of nutrients and affected viscosity of digesta in a non-linear manner.

The effects of extrusion of wheat distillers dried grains with solubles with or without an enzyme cocktail on performance of turkey hen poults

Two experiments were conducted to determine if extrusion (EX) or enzymes (E) could overcome the restrictions (e.g., high fiber) of feeding wheat distillers dried grain with solubles (wDDGS) and improve its nutritional value for feeding turkeys. Two starter diets with either 0 or 30% wDDGS were formulated to meet or exceed the nutrient requirements of the Hybrid Converter female turkeys. The 30% wDDGS diet was substituted with either non-extruded (EX-) or extruded (EX+) wDDGS to produce three basal diets [0% wDDGS (EX-) or 30% wDDGS (EX-/EX+)]. Diets were blended to obtain 15% wDDGS. In the respective treatments, only wDDGS was extruded (temperature; 118°C, retention; 15 sec, total moisture; 25% and pressure 33 bar). The respective experimental diets were supplemented with/without an enzyme cocktail (E; 0.5 g/kg). Test diets were fed from 7-21 d in a completely randomized design. In Experiment 1, a total of 210 turkey hen poults were fed diets containing 0, 15, or 30% wDDGS (EX-) with or without enzyme (E+/E-). Body weight (BW) and feed intake (FI) were significantly higher for 0% wDDGSE-. Nitrogen retention (NR) and apparent metabolizable energy (AME) for the 30% wDDGSE- was significantly higher than other treatments at 21 d. The results indicated significant main effects of E and an interaction between wDDGS level and E. In Experiment 2, 280 turkey hen poults were fed 8 diets [15/30% wDDGS (E+/E-), (EX-/EX+)]. The level of wDDGS had a significant effect on BW, FI and gain:feed; 15% inclusion was superior to 30%. There were significant 2- and 3-way interactions for AME and NR at 21 d due to differences in enzyme response with 15 or 30% wDDGS inclusion and/or extrusion of wDDGS. As high as 15% wDDGS can be incorporated in turkey hen diets. There were no beneficial effects of EX or E on poult performance.

Effects of Enzyme Complex Supplementation to a Paddy-based Diet on Performance and Nutrient Digestibility of Meat-type Ducks

Paddy rice is rarely used as a feed because of its high fiber content. In this study, two experiments were conducted to study the effects of supplementing an enzyme complex consisting of xylanase, beta-glucanase and cellulase, to paddy-based diets on the performance and nutrient digestibility in meat-type ducks. In the both experiments, meat-type ducks (Cherry Valley) were randomly assigned to four treatments. Treatment 1 was a basal diet of corn-soybean; treatment 2 was a basal diet of corn-paddy-soybean; treatment 3, had enzyme complex added to the corn-paddy-soybean basal diet at levels of 0.5 g/kg diet; and treatment 4, had enzyme complex added to the corn-paddy-soybean diet at levels of 1.0 g/kg diet. The results showed that the enzyme complex increased the ADG, and decreased the ADFI and F/G significantly (p<0.05) in the ducks, and the ADFI for the ducks fed the corn-paddy-soybean diet showed no difference compared to the ducks fed corn-soybean diets at all stages of the experiment (p<0.05). When corn was partially replaced by paddy, the digestibility of CP and NDF was decreased and increased, respectively (p<0.05), and the level of enzyme complex had a significant effect on both CP and NDF digestibility (p<0.05). As for the AME, addition of enzyme complex increased it significantly (p<0.05), but both diet types and levels of enzyme complex had no effect (p>0.05). The outcome of this research indicates that the application of enzyme complex made up of xylanase, beta-glucanase, and cellulase, in the corn-paddy-soybean diet, can improve performance and nutrition digestibility in meat-type ducks.

Chemical alterations with nutritional consequences due to pelleting animal feeds: a review

Pelleting is an energy-demanding process that is carried out on many animal feeds to assure a large macro-structure and thus improved handling properties and a high and homogenous feed intake. Due to the heat applied during conditioning and pelleting, some chemical alterations may take place. Proteins are to some extent denatured, and this will potentially improve nutritional value through inactivation of proteinous antinutrients, although may contribute negatively through inactivation of exogenous enzymes. Only a small fraction of the starch will be gelatinised, and pelleting will not affect starch digestibility to any considerable extent. Some vitamins, however, may be destroyed during the pelleting process, and viscosity of soluble fibres may increase.