Effect of Bacillus spp. direct-fed microbial on slurry characteristics and gaseous emissions in growing pigs fed with high fibre-based diets.

A 26-day trial with 18 Pietrain×(Landrace×Duroc) pigs was conducted to investigate the effect of two dose levels of a specifically selected Bacillus spp. direct-fed microbial (DFM) product, on the emission of environmentally harmful gasses (methane, ammonia and hydrogen sulphide) from manure. Pigs were assigned to one of three treatments in a randomized complete block design according to their sex and initial BW. Each treatment contained three replications with two pigs per pen. The test treatments included a Bacillus spp. DFM containing 3×108 colony-forming unit/g, added at a low (250 mg/kg) and high (500 mg/kg) dose to an antibiotic free high fibre-based diet, and a non-supplemented control diet. Manure from pigs fed with the supplemented diets emitted lower amounts of atmospheric contaminants. The most significant reduction was observed with low DFM supplementation, in which methane and ammonia volatilization decreased (P40% and 50%, respectively, on fresh weight basis in relation to the control. Microbiome analysis of manure by high through put sequencing techniques on eubacterial and archaeal 16S rRNA genes highlighted the complex interactions between indigenous gut microflora and inoculated Bacillus spp. The tested Bacillus DFM could be considered as a best available technique in reducing the environmental impacts of growing pigs fed with high fibre-based diets.

Dietary ß-galactomannans have beneficial effects on the intestinal morphology of chickens challenged with Salmonella enterica serovar Enteritidis.

Salmonella enterica serovar Enteritidis is one of the leading causes of food-borne salmonellosis in humans. Poultry is the single largest reservoir, and the consumption of incorrectly processed chicken meat and egg products is the major source of infection. Since 2006, the use of antibiotics as growth promoters has been banned in the European Union, and the dietary inclusion of ß-galactomannans (ßGM) has become a promising strategy to control and prevent intestinal infections. The aim of this study was to investigate the effect of various ßGM-rich products on intestinal morphology in chickens challenged with Salmonella Enteritidis. To assess this effect, a total of 280 male Ross 308 chickens were studied (40 animals per treatment housed in 5 cages). There were 7 treatments, including controls: uninoculated birds fed the basal diet (negative control) and inoculated birds fed the basal diet (positive control) or the basal diet supplemented with Salmosan (1 g/kg), Duraió gum (1 g/kg), Cassia gum (1 g/kg), the cell walls of Saccharomyces cerevisiae (0.5 g/kg), or the antibiotic colistine (0.8 g/kg). The birds were fed these diets from the d 1 to 23, except the animals in the colistine group, which were fed the diet containing the antibiotic only from d 5 to 11. The inoculated animals were orally infected on d 7 with 10(8) cfu of Salmonella Enteritidis. Bird performance per replicate was determined for the whole study period (23 d), and the distal ileum and cecal tonsil of 5 animals per treatment (1 animal per replicate) were observed at different magnification levels (scanning electron, light, and laser confocal microscopy). In the images corresponding to the treatments containing ßGM we observed more mucus, an effect that can be associated with the observation of more goblet cells. Moreover, the images also show fewer M cells, which are characteristic of infected animals. Regarding the morphometric parameters, the animals that received Duraió and Cassia gums show greater (P = 0.001 and P = 0.016, respectively) villus length compared with the animals in the positive control, thus indicating the capacity of these products to increase epithelial surface area. However, no effect (P > 0.05) on microvillus dimensions was detected. In conclusion, the results obtained indicating the beneficial effects of these ßGM on intestinal morphology give more evidence of the positive effects of these supplements in poultry nutrition.

Immune-modulatory effects of dietary Saccharomyces cerevisiae cell wall in broiler chickens inoculated with Escherichia coli lipopolysaccharide.

1. An experiment was conducted to study the effect of yeast (Saccharomyces cerevisiae) cell wall (YCW) supplemented in diets of broiler chickens challenged with Escherichia coli lipopolysaccharide (LPS). 2. One-day-old broiler chicks were randomly distributed into 24 cages (6 replicate cages; 8 birds/cage) and were inoculated with 0 or 1 mg/kg body weight E. coli-LPS (d 4 and 9) and 0 or 500 mg YCW/kg feed, resulting in a 2 × 2 factorial arrangement of treatments. Experimental diets did not include coccidiostats, in-feed antibiotics or enzymes. 3. On d 21, the inoculation of E. coli-LPS reduced weight gain and feed intake and increased feed conversion ratio (FCR) of birds, an effect maintained until 28 d. In contrast, chickens given diets with YCW improved the FCR at both 21 and 28 d of age. 4. E. coli-LPS challenge reduced the relative weight of bursa of Fabricius, except when chickens were given YCW, which resulted in an interaction. Supplementation of broiler diets with YCW exacerbated the cellular immune response as measured by the delayed cutaneous hypersensitivity response test. 5. The results of this study suggested a benefit on feed efficiency when YCW was added to diets fed to broiler chickens challenged with E. coli-LPS. Part of the mode of action of YCW might be related to better maintenance of immune status in response to microbial challenge.

The influence of dietary locust bean gum and live yeast on some digestive immunological parameters of piglets experimentally challenged with Escherichia coli.

Gums and yeast cells are natural mannose-rich products that can be used as subtracts for adhesion of gram-negative bacteria. The aim of the study was to investigate the role of dietary locust bean gum (LBG; Salmosan, ITPSA, Spain) or live yeast (Saccharomyces cerevisiae Sc47; Actisaf, Lesaffre, France) as immunological enhancers of the intestinal function of piglets. Treatments included a noninfected group fed with a control diet and 4 other groups orally challenged with 1x10(8) cfu of Escherichia coli K88. The challenged groups were fed the control or the control diet supplemented with colistin, LBG, or yeast. Twenty-five Landrace × Duroc piglets weaned at 4 wk were used. The animals were group housed, challenged on day 14, and euthanized 2 d later. Blood, bile, ileum, and mesenteric lymph node (MLN) samples were obtained for analysis of C-reactive protein (CRP), secretory immunoglobulin A (sIgA), and Toll-like receptors 2 (TLR2) and 4 (TLR4). Challenge increased the level of CRP of piglets fed the control diet, but this did not happen in the piglets fed the supplemented diets (P < 0.001). Challenge upregulated TLR2 in MLN and TLR4 in ileum and MLN (P < 0.05). This was prevented by yeast supplementation for the TLR2 in MLN and TLR4 in ileum. Pigs fed colistin and LBG diets showed intermediate but nonsignificant responses. In conclusion, the results suggest that colistin, live yeast, and LBG reduce the levels of CRP in blood of piglets challenged with E. coli, and yeast reduces the expression of Toll-like receptors in the intestine.

Redox potential of cecum content of growing pigs and its relation with pH and VFA concentration.

Digestive microflora is partly responsible for physiological gut conditions. Measurements of redox potential (Eh) and pH of digesta may give a basis for understanding microbial activity and dynamics of fermentation. However, few studies have assessed the Eh of the gastrointestinal tract of pigs. Twenty-four pigs of 30 kg BW were slaughtered to measure Eh and pH of cecum content in situ and to obtain samples of ileum, cecum, and colon contents for VFA determinations. Pigs had previously been fed with a nonmedicated starter feed for 5 wk. Measurements of Eh and pH were recorded first at 2 min and then at 5-min intervals for 35 min to estimate kinetics and the delay to reach stabilization of the Eh value. Cecum Eh rapidly decreased (P < 0.001) from -115 to -180 mV after 15 min of insertion of the electrodes and then slowly decreased until -185 mV at 35 min. Cecal pH started at 5.74 and decreased (P < 0.01) slowly afterwards until 5.53 after 35 min. The Eh value after stabilization was negatively correlated (r = -0.64; P < 0.001) with final pH. Acetic, propionic, and butyric acids accounted for 58.7, 24.0, and 12.8%, respectively, of total VFA production of cecum content. The VFA production of ileal content was lower (P < 0.001) when compared to cecum or colon (50.8, 142.1, and 130.8 µmol/g, respectively) and a higher proportion of formic and lactic acids was detected (32.3 and 27.0%, respectively). Proportions of acetic and propionic acids were negatively (r = -0.53; P < 0.01) and positively (r = 0.66; P < 0.001) correlated with Eh, respectively. In conclusion, Eh measured after stabilization seemed to be a meaningful predictor of hindgut fermentative activity.

Effects of different yeast cell wall supplements added to maize- or wheat-based diets for broiler chickens.

1. Three experiments were carried out to study the effects of two experimental yeast cell wall (YCW) supplements, one from the yeast extract industry and the other from the brewery industry, added to maize or wheat based-diets, on performance and intestinal parameters of broiler chickens (Ross 308). 2. In the first and second experiments, a completely randomised block design with 4 experimental treatments was used: T-1) Negative control, no additives T-2) Positive control, avilamycin group (10 mg/kg feed), T-3) Yeast extract-YCW (500 mg/kg), and T-4) Brewery-YCW (500 mg/kg feed). There were 6 replicates of 20 (experiment 1) and 22 (experiment 2) chicks per treatment. 3. In experiment 1 (wheat based diets), yeast extract-YCW increased BW and daily feed intake (42 d). The effects were comparable to those of avilamycin. In experiment 2 (maize based diet), avilamycin, yeast extract-YCW and brewery-YCW treatments improved the feed conversion ratio with respect to the negative control group (0 to 14 d). 4. At 24 d, in both experiments, the ileal nutrient digestibility and ileal bacterial counts were not affected by any experimental treatment. In maize diets, lower intestinal viscosity was obtained with avilamycin, yeast extract-YCW and brewery-YCW than with the negative control. In wheat diets, yeast extract-YCW and brewery-YCW reduced intestinal viscosity. 5. A third experiment was conducted to study the effect of yeast extract-YCW on animal performance, intestinal mucosa morphology and intestinal viscosity. A 2 x 2 factorial arrangement of treatments was used; one factor was the dietary yeast extract-YCW supplementation (0 or 500 mg/kg feed) and the other the cereal in the diet (maize or wheat). 6. At 43 d, the heaviest BW was in chickens fed on yeast extract-YCW compared to those given the negative control. At 22 d, yeast extract-YCW increased villus height, mucus thickness and number of goblet cells with respect to negative control. 7. Results of these experiments suggest that supplementation of yeast extract-YCW to broiler chicken diets increased animal performance by favouring intestinal mucosal development.

Reduction of Salmonella enterica var. Enteritidis colonization and invasion by Bacillus cereus var. toyoi inclusion in poultry feeds.

The effect of continuously feeding the probiotic microorganism Toyocerin to birds inoculated with Salmonella Enteritidis field-isolated strains on Salmonella Enteritidis prevalence, and performance variables were studied in 2 experiments. The experiments were performed with 1) broiler chickens in floor pens until slaughter 42 d of age, challenge was performed on d 3, 7, or 14 with 2 x 10(6) cfu per chick, and 2) Single Comb White Leghorn chickens in cages until 28 d of age, challenge was performed on d 7 with 10(8) cfu per chick. The inclusion of Toyocerin in feed of inoculated broiler chickens did significantly (P < 0.05) improve ADG (by 3.4 g), BW (by 141 g), and feed conversion ratio (by -0.060 kg/kg) at the end of the trial at 42 d compared with inoculated and untreated birds. At the end of the trial at 42 d, the slaughter age, 42% of untreated birds were still positive for Salmonella, whereas Salmonella was not detected in Toyocerin-treated birds. In Leghorn chickens, at 3 wk after inoculation (the end of the trial), only 38% of birds from the Toyocerin-treated groups were Salmonella-positive, whereas 63% of birds were still Salmonella-positive in the untreated control treatment. No significant differences were detected in performance variables in Leghorn chickens. The results of the present experiments indicate that feeding Toyocerin reduced the prevalence of Salmonella in poultry and in the case of broiler chickens also significantly improved performance variables at slaughter age.

Use of yeast cell walls; beta-1, 3/1, 6-glucans; and mannoproteins in broiler chicken diets.

Two experiments were carried out to evaluate the effect of dietary addition of yeast cell wall (YCW); beta-1, 3/1, 6-glucan (BG); and mannoprotein complex (MP) purified fractions in broilers. In experiment 1, there was a control diet and 5 experimental diets containing, respectively: 10 mg of avilamycin (AVI)/kg of feed, 500 mg of YCW/kg of feed, 95 mg of MP/kg of feed, 145 mg of BG/kg of feed, and 95 mg of MP plus 145 mg of BG/kg of feed. All birds were vaccinated via drinking water against Newcastle disease virus at 9 d of age. At 42 d, chickens fed AVI, YCW, MP + BG, and BG diets had similar BW not significantly different from chickens fed the control diet. The antibody response of Newcastle disease virus vaccine was not affected by any experimental treatment. Broilers fed MP + BG diet had greater thymus weights (P

Occurrence and bioaccumulation study of PCDD and PCDF from mineral feed additives.

Extraction of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was evaluated in sepiolite matrices. Soxhlet extraction using different extracting strategies and acid treatment were tested. Acid treatment or Soxhlet extraction using a mixture of toluene:ethanol as solvent allowed to reach the minimum requirements for recovery rates. However, Soxhlet extraction using a mixture cyclohexane:toluene as extracting solvent did not allow to comply with these minimum requirements. Significant differences were obtained in TEQ units when acid treatment was applied in comparison to Soxhlet extraction. This fact can be explained because the use of drastic acid conditions allows removing strongly adsorbed analytes which can be uniquely extracted after a total destruction of the crystalline. On the contrary, Soxhlet extraction was not able to destroy the structure of sepiolite and as a consequence the PCDDs/Fs remain adsorbed in the internal structure of the mineral. A bioaccumulation study was also conducted to evaluate the transference of PCDDs/Fs from the sepiolite into the animal when fed with feed containing sepiolite. Four groups of chickens were exposed through diet to a control feed, feed with 3% w/w sepiolite, spiked feed contaminated with PCDDs/Fs and feed containing contaminated kaolinitic clay. Livers of animals were analyzed throughout the exposure period. Results of this trial showed that the performance of broilers was not affected by the presence of dioxins at levels tested, and chickens did not show any abnormal behaviour. Dioxins intentionally added to the diet were significantly absorbed and accumulated in liver, whereas the PCDDs/Fs from sepiolite were not available for chickens since livers from broilers fed 3% sepiolite presented similar WHO-TEQ values than those from broilers fed control diet.

Effects of an experimental phytase on performance, egg quality, tibia ash content and phosphorus bioavailability in laying hens fed on maize- or barley-based diets.

A 24-week performance trial was conducted to evaluate the efficacy of an experimental phytase on performance, egg quality, tibia ash content and phosphorus excretion in laying hens fed on either a maize- or a barley-based diet. At the end of the trial, an ileal absorption assay was conducted in order to determine the influence of phytase supplementation on the apparent absorption of calcium and total phosphorus (P). Each experimental diet was formulated either as a positive control containing 3.2 g/kg non-phytate phosphorus (NPP), with the addition of dicalcium phosphate (DCP), or as a low P one, without DCP addition. Both low P diets (containing 1.3 or 1.1 g/kg NPP) were supplemented with microbial phytase at 0, 150, 300 and 450 U/kg. The birds were housed in cages, allocating two hens per cage as the experimental unit. Each of 10 dietary treatments was assigned to 16 replicates. Low dietary NPP (below 1.3 g/kg) was not able to support optimum performance of hens during the laying cycle (from 22 to 46 weeks of age), either in maize or barley diets. Rate of lay, daily egg mass output, feed consumption, tibia ash percentage and weight gain were reduced in hens fed low NPP diets. The adverse effects of a low P diet were more severe in hens on a maize diet than in those on a barley diet. Low dietary NPP reduced egg production, weight gain, feed consumption and tibia ash content and microbial phytase supplementation improved these parameters. Hens given low NPP diets supplemented with phytase performed as well as the hens on positive control diets containing 3.2 g/kg of NPP. A 49% reduction of excreta P content was achieved by feeding hens on low NPP diets supplemented with phytase, without compromising performance. Phytase addition to low NPP diets increased total phosphorus absorption at the ileal level, from 0.25 to 0.51 in the maize diet and from 0.34 to 0.58 in the barley diet. Phosphorus absorption increased linearly with increasing levels of dietary phytase. Mean phosphorus absorption was higher in barley diets than in maize diets (0.49 vs 0.39).

Assessment of potential interactions between phytase and glycosidase enzyme supplementation on nutrient digestibility in broilers.

The effects of microbial 3-phytase and glycosidase enzymes, and their interactions, on energy values and nutrient digestibility in diets rich in nonstarch polysaccharides (NSP) were studied in diets based on corn, wheat, or barley. Four diets were prepared with each cereal grain. One had no enzymes, a second had 500 units of phytase, a third had glycosidase enzyme, and a fourth had phytase and glycosidase. The glycosidases used were alpha-galactosidase (corn diet), xylanase (wheat), and beta-glucanase (barley). Glycosidase decreased intestinal viscosity, whereas phytase increased this parameter in corn diets. Phytase increased AME in corn diets, whereas beta-glucanase in barley diets improved AME and AMEn, and digestibility of dry matter, starch, beta-glucans, and lipid. Xylanase in wheat diets improved dry matter and starch digestibility. Phytase increased total phosphorus retention in all diets, and significant interactions between glycosidase enzymes and phytase were detected in wheat and barley diets. Phytase decreased phosphorus excretion in corn and barley diets, whereas alpha-galactosidase increased phosphorus excretion in corn diets. Phytase in corn diets and beta-glucanase in barley diets increased calcium retention, whereas inclusion of xylanase decreased calcium retention in wheat diets. Phytase and beta-glucanase decreased calcium excretion in corn- and barley-based diets, respectively. An interaction was detected between phytase and beta-glucanase in barley diets, in which calcium excretion was reduced. In general, no negative interactions between phytase and glycosidase enzymes were found, indicating that both types of enzymes may be used together in feeds based on corn, wheat, or barley.

Effect of fishmeal replacement with spray-dried animal plasma and colistin on intestinal structure, intestinal microbiology, and performance of weanling pigs challenged with Escherichia coli K99.

We evaluated spray-dried animal plasma (SDAP) as an alternative to antimicrobial medication with colistin sulfate in weanling pigs challenged with Escherichia coli K99. Forty-eight piglets weaned at 24 d of age were distributed into 12 pens, and each pen was assigned to one of four dietary treatments. All the piglets were given an oral dose of 5 x 10(7) cfu of E. coli K99 at weaning. The dietary treatments followed a factorial arrangement with two levels of SDAP (0 and 7%) and two levels of colistin (0 and 300 mg/kg of diet). The ADG and ADFI were measured on d 7 and 14 of trial. Three piglets from each treatment were killed on d 7 and 14 to remove the small intestine, and to obtain ileal and cecal digestive contents. The inclusion of SDAP improved ADG by 68 g (P < 0.05) and ADFI by 41 g (P < 0.10) in wk 1 of trial. During wk 2, SDAP improved ADG by 41 g (P < 0.10) and gain:feed ratio (G:F) by 25% (P < 0.01). On the other hand, whereas colistin had no effect on performance in wk 1, it improved ADG by 102 g (P < 0.01), ADFI by 62 g (P < 0.01), and G:F by 26% (P < 0.01) in wk 2. Over the 14 d of the trial, ADG was improved by 54 (P < 0.05) and 75 g (P < 0.05), and G:F was improved by 35 (P < 0.05) and 32% (P < 0.05) due to SDAP and colistin, respectively. There was interaction between colistin and SDAP for ADFI in wk 2 and between d 0 to 14 (P < 0.05), which indicates that their effects were not additive. The use of colistin was advantageous in the maintenance of the integrity of the intestinal mucosa of the pigs, as suggested by a small intestine that was 93 g heavier (P < 0.10) and with the tallest villi 106 microm longer (P < 0.10) than in pigs without colistin. The inclusion of SDAP in the diet favored the growth of lactobacilli in the ileum (P < 0.10) and the cecum (P < 0.05), whereas colistin reduced the number of enterococci in the cecum (P < 0.05) and of Escherichia coli both in the ileum and the cecum (P < 0.001). These results suggest that SDAP may be an alternative to medicated feed with antibiotics since it provided a level of protection against an experimental challenge with E. coli K99 similar to that obtained with colistin, an antibiotic of proven efficacy. The current situation in which the use of antimicrobials in animal feeding is being questioned should encourage further investigation into the use of SDAP as a means of preventing disease in pigs at weaning.

Influence of source and ratio of xanthophyll pigments on broiler chicken pigmentation and performance.

One experiment was conducted using 960 1-d-old, sexed broilers of Ross 308 strain from 1 to 43 d to evaluate if one type of chemically isomerized marigold with 25% of xanthophylls as zeaxanthin (SME-25) could produce pigmentation equivalent to the current addition of conventional marigold with 10% of xanthophylls as zeaxanthin (SME-10) plus canthaxanthin (CTX) in practical broiler diets (maize-wheat-soybean). Birds were allocated in 32 pens, in a randomized complete block design (four blocks x four treatments). The treatments consisted of a nonpigmented control (T1), a combination of 35 ppm of yellow xanthophylls (YX) from SME-10 + 5 ppm of CTX (T2), a combination of 32 ppm of YX from SME-10 + 2 ppm of CTX (T4), and one treatment with 40 ppm of YX from a new SME-25 (T3). There were no significant treatment effects on chicken performance. All color parameters (Minolta coordinates, Roche color fan scores, Rank test) presented significant differences (P < 0.0001) because of dietary pigments on shanks and breast skin. Birds fed the SME-25 diet had less pigmentation than those fed equivalent quantities of a combination of SME-10 + CTX. The Minolta coordinate "b" measured in breast skin was a good indicator of YX content in feed, whereas the "a" coordinate measured on the shank showed a linear relationship with the dietary CTX level (r = 0.61, P < 0.0001). The same visual color classification of chickens was achieved irrespective of the rank test performed (by shank or carcass color). Lutein and zeaxanthin from the SME-25 product had lower deposition rates in skin and fat tissues than those from the SME-10 product. This finding seems to be related to the ratio of zeaxanthin stereoisomer RR (optically active) vs. RS that was found in tissues from the SME-10 product (97.8%:2.2%), whereas with SME-25 this ratio was 16.0:84.0%. These results suggest that inclusion of only the SME-25 product could not replace the current addition of SME-10 and CTX combinations.

Influence of growing season, tannin content and autoclave treatment on the nutritive value of near-isogenic lines of faba beans (Vicia faba L.) when fed to leghorn chicks.

1. The objective of this study was to determine the influence of heat-treatment (autoclaving) on the utilisation by chicks of near-isogenic lines of faba beans that were either tannin-free (Winter-white or Spring-white) or had tannins in the seed coat (Winter-coloured or Spring-coloured). The effect of heat treatment on a common tannin-containing cultivar, Diana, was also studied. 2. The nitrogen-corrected apparent metabolisable energy (AMEn) values of diets containing 600 g faba beans/kg diet were affected by tanning content and autoclave treatment of faba beans, with 59% of total variance in AMEn being attributable to the effect of autoclaving. The AMEn values were 9% higher for chicks fed on the autoclaved compared with those fed on diets containing the raw faba beans, 5% higher for the near-isogenic faba beans with no tannins compared with those with tannins, and 4% higher for the Winter compared with the Spring cultivars. 3. The above study was carried out on droppings obtained by total collection. Similar but not identical trends were obtained when AMEn was calculated using the chromic oxide index method (r = 0.91). 4. Both autoclaving and the use of tannin-free faba beans improved the apparent protein digestibility (APD) of the diets by similar amounts (4% as determined by the total collection method and 6% as determined by the chronic oxide index method). 5. The digestibility of most amino acids either alone or together was affected by a cultivar x tannin x processing interaction. The cultivar by tannin interaction demonstrated that autoclaving increased the digestibility of amino acids to a greater degree when the tannin-containing (for example, 9% for lysine) than when the tannin-free faba beans (4% for lysine) were used in the diets. 6. The improvements in AMEn, APD and total amino acid digestibilities of faba beans following heat treatments ranged from 18% to 33%, 5% to 16% and 5% to 11%, respectively. The results demonstrate that the method of analysis can affect the values obtained but that they do not change the overall pattern of results. The results also suggest that, in most cases, more than half of the response to heat treatment is associated with the inactivation of tannins while the balance of the response is attributable to an effect of heat treatment on the non-tannin-containing factors. In summary, heat treatment can improve the utilisation of faba bean by chickens especially when they contain tannins. 7. Chicks, unlike rats, do not seem to adapt to tannins as the excretion of 3 amino acids that are the main constituents of a proline-rich protein were not affected by dietary tannins.

Effect of inclusion of sugar beet pulp, pelleting and season on laying hen performance.

1. The effect of three metabolisable energy (ME) concentrations 12.2, 11.3 and 10.5 MJ ME/kg and two forms of diet (mash and pellet) on egg production in summer and winter were studied. The different ME values were obtained by diluting the 12.2 MJ ME/kg diet with sugar beet pulp of 2.88 MJ/kg DM. In a 3rd summer experiment the water intake of hens on these diets was examined. Data were analysed by factorial analysis of variance, and the relationship between performance and dietary energy concentration was examined by regression analysis. 2. The use of low energy diets (10.5 to 11.3 MJ ME/kg) decreased egg production in both seasons, but pelleting diets improved egg production and egg weight in summer. Egg weight was not affected by energy density in winter, but decreased in the summer when energy density increased. 3. In winter, food consumption was not affected by the dietary ME, while in summer food consumption increased when the dietary ME increased. Therefore, energy intake was not the same at all energy densities, but tended to increase as the energy density increased. 4. In summer, pelleting improved food efficiency and egg production and increased water consumption and the ratio of water to food intake. Water intake and water: food ratio decreased with increasing dietary energy concentration.

Bioefficacy of enzyme preparations containing beta-glucanase and xylanase activities in broiler diets based on barley or wheat, in combination with flavomycin.

The objective of the study was to determine the effects of two enzyme preparations containing beta-glucanase and xylanase activities on barley- and wheat-based diets, respectively, for broilers, in combination with flavomycin. In addition, the stability of the enzyme preparations after pelleting was measured. Temperatures recorded during the pelleting process reached 75 to 80 C, and the activities recovered with respect to the amounts present in the mash feed before pelleting were 80% or higher. Two performance experiments were conducted simultaneously under the same conditions over 6 wk. In addition, intestinal viscosity and incidence of vent pasting were measured and carcasses were eviscerated to determine abdominal fat, carcass yield, and percentage weight of intestines and viscera. Twenty-four pens (12 per sex), each containing 75 chickens were used in each experiment. Wheat- or barley-based diets were supplemented with flavomycin and a xylanase or a beta-glucanase preparation, respectively, in a 2 x 2 factorial arrangement of treatments. In the wheat diets, xylanase and flavomycin improved feed efficiency, in parallel with a reduction of intestinal viscosity. Xylanase reduced the incidence of vent pasting and the percentage viscera, especially of intestines, and increased abdominal fat. In the barley diets, beta-glucanase and flavomycin improved feed conversion. beta-Glucanase also reduced intestinal viscosity and vent pasting. Both beta-glucanase and flavomycin reduced percentage intestines, but the effects were not additive. In general, the effects of the enzyme preparations and flavomycin were independent, except for percentage intestines with beta-glucanase.

Determination of beta-(1-3),(1-4)-D-glucans in barley by reversed-phase high-performance liquid chromatography.

An HPLC method for the determination of beta-glucan in barley was developed. The beta-glucan was hydrolysed with lichenase [endo-beta-(1-3),(1-4)-D-glucan-4-glucanhydrolase from Bacillus subtilis] to oligosaccharides, which were analysed by reversed-phase HPLC using water as the mobile phase at a flow-rate of 0.7 ml/min. The separation of the oligosaccharides was performed in a C18 stainless-steel column (Spherisorb ODS-2) with 5-microns particles in less than 10 min, with a refractive index detection.

The differences in intestinal viscosity produced by barley and beta-glucanase alter digesta enzyme activities and ileal nutrient digestibilities more in broiler chicks than in cocks.

The objectives of this study were to determine whether intestinal viscosity caused by mixed linked barley beta-glucan depresses ileal nutrient digestibility and digestive enzyme activities and to determine the interaction of intestinal viscosity, digestive enzyme activities and ileal nutrient digestibility in different ages of poultry. In Experiments 1 and 2, 1-d-old broiler chicks and 1-y-old cocks, respectively, were fed diets with 60% corn, low and high viscosity barley with or without beta-glucanase, for 3 wk. A 3 x 2 factorial design was used. Comparisons were made only within the same age group. In Experiment 3, 1-d-old broiler chicks were fed high viscosity barley with and without beta-glucanase to measure fecal nutrient and ileal and fecal amino acid digestibility. Broiler chicks fed barley ate less and gained less weight than those fed corn; added beta-glucanase resulted in increases in both food consumption and weight gain for the barley-fed chicks (P < 0.05). Relative pancreas weight was higher (P < 0.05) in chicks fed barley than in those fed corn, and lower with beta-glucanase (P < 0.05). Digesta from barley-fed birds had the highest viscosities, which were decreased (P < 0.05) by beta-glucanase. Amylase and lipase were lower in broiler chicks fed high viscosity barley compared with corn (P < 0.05), and beta-glucanase increased both activities and that of trypsin as well (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of cultivar, pelleting and enzyme addition on nutritive value of barley in poultry diets.

1. The effect of pelleting process and Trichoderma viride enzymes (TVE) addition on apparent metabolisable energy, corrected for nitrogen balance (AMEn) and on productive value of practical diets containing 40 and 45% of three different barley cultivars and one wheat were studied in poultry. 2. The effect of the pelleting process on AMEn was inconsistent and was dependent on the cereal included and the addition of enzyme. 3. The growth trial showed a significant effect of enzyme addition to pelleted diets over the whole growth period (0 to 42 d). Addition of TVE improved weight gain and food efficiency by 1.3% and 2.9%, respectively and decreased food intake by 1.6% between 0 and 22 d. In the finisher period (23 to 42 d) TVE improved efficiency by 2.8% and reduced food intake by 2.9%. 4. The incidence of sticky droppings was related to the viscosity of barley used, and enzyme supplementation reduced it. Both pelleting and enzyme addition increased dry matter content of excreta. 5. At the end of the experiment, 14 animals per treatment were slaughtered and carcass yield, viscera weight and abdominal fat were determined.