• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1642-1649
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• 2003

An experiment was conducted to evaluate the effects of phytase supplementation on the growth performance, nutrients utilization and bone mineralization in broiler chickens. Day-old broiler chicks (n=480) were equally devided into eight treatment groups and fed maize or wheat based isocaloric, isonitrogenous and isocalcium diets having two non phytate phosphorus (NPP) concentrations (0.50% and 0.30%) and two phytase levels (0 and 500 phytase units/kg diet) in a 42 days growth trial. Maize based dietary treatments were MC (NPP 0.50%, MN (NPP 0.30%), MNP (MN+500 units of phytase) and MCP (MC+500 units of phytase), whereas wheat based experimental diets were WC (NPP 0.50%), WN (NPP 0.30%), WNP (WN+500 units of phytase) and WCP (WC+500 units of phytase). The NPP levels were maintained by dicalcium phosphate. Reduction in dietary NPP depressed live weight gain and feed intake and increased feed conversion ratio (FCR). Phytase supplementation to low NPP (0.30%) diets significantly (p<0.05) improved the growth performances of broilers. The supplementation to low NPP diets allowed complete, safe and economic replacement of dietary inorganic P (dicalcium phosphate) to reduce feed cost per kg live weight gain of broilers. Reduction in dietary NPP did not affect retention of nutrients except phosphorus (P) but had a significant (p<0.05) depression in tibia ash and minerals (Ca, P) concentration in serum and tibia ash. Phytase supplementation at low NPP level was effective (p<0.05) in improving the retention of dry matter, Ca and P and Ca and P concentration in serum and tibia ash. However, the supplementation was not effective at high level of NPP (0.50%). There were no significant (p>0.05) differences in carcass quality among dietary treatments. The response of phytase was greater in low NPP and maize based diets as compared with high NPP and wheat based diets, respectively. The results show that phytase supplementation to low NPP (0.30%) diets improved the growth performance, relative retention of nutrients (N, Ca and P) and minerals (Ca, P) status of blood and bone in broiler chickens, with a better efficacy in maize based diets.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.394-402
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• 2003

Individual and combined supplementation of phosphorus-adequate, wheat-based broiler diets with exogenous phytase and xylanase was evaluated in three experiments. The effects of the enzyme combination in lysine-eficient diets containing wheat and sorghum were more pronounced than those of the individual feed enzymes. The inclusion of phytase plus xylanase improved (p<0.05) weight gains (7.3%) and feed efficiency (7.0%) of broilers (7-28 days post-hatch) and apparent metabolisable energy (AME) by 0.76 MJ/kg DM. Phytase plus xylanase increased (p<0.05) the overall, apparent ileal digestibility of amino acids by 4.5% (0.781 to 0.816); this was greater than the responses to either phytase (3.6%; 0.781 to 0.809) or xylanase (0.7%; 0.781 to 0.784). Absolute increases in amino acid digestibility with the combination exceeded the sum of the individual increases generated by phytase and xylanase for alanine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, phenylalanine, threonine, tyrosine and valine. These synergistic responses may have resulted from phytase and xylanase having complementary modes of action for enhancing amino acid digestibilities and/or facilitating substrate access. The two remaining experiments were almost identical except wheat used in Experiment 2 had a higher phytate concentration and a lower estimated AME content than wheat used in Experiment 3. Individually, phytase and xylanase were generally more effective in Experiment 2, which probably reflects the higher dietary substrate levels present. Phytase plus xylanase increased (p<0.05) gains (15.4%) and feed efficiency (7.0%) of broiler chicks from 4-24 days post-hatch in Experiment 2; whereas, in Experiment 3, the combination increased (p<0.05) growth to a lesser extent (5.6%) and had no effect on feed efficiency. This difference in performance responses appeared to be 'rotein driven'as the combination increased (p<0.05) nitrogen retention in Experiment 2 but not in Experiment 3; whereas phytase plus xylanase significantly increased AME in both experiments. In Experiments 2 and 3 the combined inclusion levels of phytase and xylanase were lower that the individual additions, which demonstrates the benefits of simultaneously including phytase and xylanase in wheat-based poultry diets.

• Animal Bioscience
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• v.34 no.6
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• pp.1049-1060
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• 2021

Objective: This study assessed the effect of different levels of xylanase, β-glucanase and phytase on intestinal enzyme activities and tibia bone development in broiler chickens fed wheat-based diets. Methods: Twelve experimental diets were formulated using a 3×2×2 factorial design (three doses of phytase and two doses of both xylanase and β-glucanase) and offered to 648 day-old Ross 308 male chicks having 6 replicates groups with 9 birds per replicate and lasted for 35 days. Results: An interaction between the enzymes products improved (p<0.01) the activity of chymotrypsin. Protein content at d 10 was highest (p<0.001) with addition of phytase while general proteolytic activity (GPA) (p<0.02) and lipase activity (p<0.001) were decreased. At d 24, there were improvements in protein content (p<0.01) and lipase (p<0.04) with supplementation of superdose phytase. Addition of superdose phytase decreased in chymotrypsin (p<0.02), trypsin (p<0.01) and GPA (p<0.001). The optimum dose of xylanase decreased the chymotrypsin activity (p = 0.05), while the GPA (p<0.001) was increased with the optimum level of β-glucanase. Superdose phytase supplementation at d 10 improved maltase (p = 0.05), sucrase (p<0.001) and alkaline phosphatase (p<0.001) activities in the jejunum while aminopeptidase activity was highest (p<0.005) with the low level of phytase. Protein content of jejunum mucosa was bigger (p<0.001) in birds fed superdose phytase while maltase activity (p<0.001) at d 24 was reduced by this treatment. Sucrase (p<0.04) and aminopeptidase activities (p<0.001) improved when diets supplemented with low levels of phytase. Tibia bone breaking strength was highest (p<0.04) with addition of low level of superdose phytase or optimum level of β-glucanase. Bone dry matter content decreased (p<0.04) when diets supplemented with phytase. Conclusion: From the results obtained in this study, supplementation of superdose phytase was the most effective, however, the cost-benefit analysis of the use of such a dose needs to be evaluated.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.137-142
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• 2008

This study was conducted to investigate the effect of single or mixed supplementation of bacterial and fungal phytase using 45-wk-old 450 Hy-Line Brown laying hens housed in individual cages for 12-wk period. The birds were reallocated to have similar egg productivity by examining the egg production for one wk before starting the experiment. Two sources of phytase, bacterial (BP) and fungal (FP), were used either in single or mixture to determine the effects of these phytase. Five dietary treatments consisted of control (BP 0, FP 0), T1 (BP 300, FP 0), T2 (BP 300, FP 300), T3 (BP 300, FP 3000), and T4 (BP 0, FP 3000). The DPU was used for phytase activity in this experiment. The nonphytate phosphorus (NPP) content of control was 0.30%, and those of phytase treatments were set to 60% of the Control. Experimental diets were fed ad libitum throughout the experimental period. The lighting schedule of 17L7D was employed. The egg production was not different between control and bacterial phytase treatments, but the T4 showed significantly low productivity compared to control (P<0.05). No difference was found in average egg weight among all treatments. The daily egg mass did not show any statistical differences among all treatments: however, it was significantly low in T4 compared to ther control during the latter half of the experiment (P<0.05). No significant difference was found among treatments in terms of feed intake, feed conversion and egg quality. The digestibilities of dry matter, crude protein, and fat digestibility were similar regardless of the treatments. No significant trends were detected in Ca and P availability. In conclusion, the BP level of 300 DPU contributed to achieve 40% reduction of recommended nonphytate phosphorus addition. The synergistic effect of bacterial and fungal phytase was not confirmed.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.651-656
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• 1999

In current animal production in Japan, a large surplus of nitrogen and phosphorus is given to animals as their feed which are mostly imported from outside of our own country. Today, an excess of nitrogen and phosphorus from animal manure has been spread out of the area of animal production and the surroundings. These components have become the major reason for eutrophication of ground, surface and inland water. Nutritional studies for the reduction of nitrogen and phosphorus from animal waste has been done by many researchers. The reduction of excess protein in animal feed and the supplementation of deficient essential amino acids to feed have a possibility to increase the biological value of feed and to reduce nitrogen excretion, especially, via urine. The use of phytase activity to degrade phytate and to release utilizable inorganic phosphorus make it possible to cut an excess supply of feed additive inorganic phosphorus and to reduce phosphorus excretion from animal waste.

• BMB Reports
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• v.37 no.3
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• pp.282-291
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• 2004

Phytases catalyze the release of phosphate from phytic acid. Phytase-producing microorganisms were selected by culturing the soil extracts on agar plates containing phytic acid. Two hundred colonies that exhibited potential phytase activity were selected for further study. The colony showing the highest phytase activity was identified as Aspergillus niger and designated strain 113. The phytase gene from A. niger 113 (phyI1) was isolated, cloned, and characterized. The nucleotide and deduced amino acid sequence identity between phyI1 and phyA from NRRL3135 were 90% and 98%, respectively. The identity between phyI1 and phyA from SK-57 was 89% and 96%. A synthetic phytase gene, phyI1s, was synthesized by successive PCR and transformed into the yeast expression vector carrying a signal peptide that was designed and synthesized using P. pastoris biased codon. For the phytase expression and secretion, the construct was integrated into the genome of P. pastoris by homologous recombination. Over-expressing strains were selected and fermented. It was discovered that ~4.2 g phytase could be purified from one liter of culture fluid. The activity of the resulting phytase was 9.5 U/mg. Due to the heavy glycosylation, the expressed phytase varied in size (120, 95, 85, and 64 kDa), but could be deglycosylated to a homogeneous 64 kDa species. An enzymatic kinetics analysis showed that the phytase had two pH optima (pH 2.0 and pH 5.0) and an optimum temperature of $60^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.985-993
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• 2017

Objective: The objective of this study was to evaluate increasing doses of a novel microbial phytase (Cibenza Phytaverse, Novus International, St. Charles, MO, USA) on standardized total tract digestibility (STTD) of P in canola meal (CM), corn, corn-derived distiller's dried grains with solubles (DDGS), rice bran (RB), sorghum, soybean meal (SBM), sunflower meal (SFM), and wheat. Methods: Two cohorts of 36 pigs each (initial body weight = $78.5{\pm}3.7kg$) were randomly assigned to 2 rooms, each housing 36 pigs, and then allotted to 6 diets with 6 replicates per diet in a randomized complete block design. Test ingredient was the only dietary source of P and diets contained 6 concentrations of phytase (0, 125, 250, 500, 1,000, or 2,000 phytase units [FTU]/kg) with 0.4% of $TiO_2$ as a digestibility marker. Feeding schedule for each ingredient was 5 d acclimation, 5 d fecal collection, and 4 d washout. The STTD of P increased (linear or exponential $p{\leq}0.001$) with the inclusion of phytase for all ingredients. Results: Basal STTD of P was 37.6% for CM, 37.6% for corn, 68.6% for DDGS, 10.3% for RB, 41.2% for sorghum, 36.7% for SBM, 26.2% for SFM, and 55.1% for wheat. The efficiency of this novel phytase to hydrolyze phytate is best described with a broken-line model for corn, an exponential model for CM, RB, SBM, SFM, and wheat, and a linear model for DDGS and sorghum. Based on best-fit model the phytase dose (FTU/kg) needed for highest STTD of P (%), respectively, was 735 for 64.3% in CM, 550 for 69.4% in corn, 160 for 55.5% in SBM, 1,219 for 57.8% in SFM, and 881 for 64.0% in wheat, whereas a maximum response was not obtained for sorghum, DDGS and RB within the evaluated phytase range of 0 to 2,000 FTU/kg. These differences in the phytase concentration needed to maximize the STTD of P clearly indicate that the enzyme does not have the same hydrolysis efficiency among the evaluated ingredients. Conclusion: Variations in enzyme efficacy to release P from phytate in various feedstuffs need to be taken into consideration when determining the matrix value for phytase in a mixed diet, which likely depends on the type and inclusion concentration of ingredients used in mixed diets for pigs. The use of a fixed P matrix value across different diet types for a given phytase concentration is discouraged as it may result in inaccurate diet formulation.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.691-700
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• 2019

Objective: This study was conducted to assess increasing doses of phytase added to broiler diets formulated with different levels of available phosphorus (avP), calcium (Ca), and sodium (Na), and the respective effects on performance parameters, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of organs. Methods: Three different matrices were assumed for phytase with the following nutritional values: matrix A (MT A): 0.165% Ca, 0.150% avP, and 0.035% Na; matrix B (MT B): 0.215% Ca, 0.195% avP, and 0.045% Na; matrix C (MT C): 0.245% Ca, 0.225% avP, and 0.053% Na. There were six different diets: No phytase (formulated to meet the nutritional requirements); phytase 500 FTU/kg+MT A; phytase 1,000 FTU/kg+MT A; phytase 1,500 FTU/kg+MT A; phytase 1,000 FTU/kg+MT B and phytase 1,500 FTU/kg+MT C. Results: There was no significant phytase influence on performance, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of the organ throughout the study period, however, it was possible to observe a tendency of improvement in body weight corrected feed conversion for broilers fed the phytase 1,500+MT C diet, where potentially these birds were more efficient on utilize phytic phosphorus and other nutrients bounded to phytate molecule, translating into improvement in performance, and there was also a non significant numerical improvement in body weight corrected feed conversion of broilers fed this diet. Conclusion: Broilers fed with diets formulated with different levels of avP, Ca, and Na and increasing doses of phytase have shown no change on performance, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of organs.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.177-187
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• 2014

Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (> $150{\mu}m$), soy bean meal (SB), corn meal (< $150{\mu}m$) (CM), and maltodextrin as drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1490-1495
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• 2010

Two experiments were conducted to evaluate the effects of addition of sodium polyacrylate (SPA) to a phytasesupplemented diet on the performance and phosphorus (P) retention of chicks. In experiment 1, chicks were randomly allocated to four dietary treatments which were fed from 7 to 21 days of age: i) basal diet (low nonphytate phosphorus (0.23% NPP)); ii) basal with 250 U/kg diet of phytase; iii) as (ii) with 2.5 g/kg diet of SPA; and iv) as (ii) with 5.0 g/kg diet of SPA. In experiment 2, three replicates, each with three chicks, were fed from 7 to 28 days of age the basal diet (0.23% NPP) with supplementation of phytase (0, 300, 600, 900 U/kg diet) and SPA (0, 2.5 g/kg diet) in a $4{\times}2$ factorial arrangement. In Experiment 1, feed efficiency was improved and excreted P was 10% less with phytase supplementation. However, the addition of SPA did not affect performance or P excretion. Dietary SPA supplementation to the diets showed significantly higher amounts of P retention, and highest values were observed in chicks fed 2.5 g/kg of the SPA-supplemented diet. In Experiment 2, feed efficiency was improved with phytase supplementation, and the addition of SPA showed significant improvement in feed efficiency. Excreted P was significantly lower in chicks fed SPA-supplemented diets, and the retained P coefficient improved with SPA supplementation. In conclusion, the increased transit time of digesta with suitable supplementation levels of SPA may allow phytase activity to be more effective in the degradation of phytate, and improve P retention.