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Query: EC:3.1.3.8 (phytase)
 1,997 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Positive effects of dietary phytase supplementation on pig performance are observed not only when phosphorus is limiting. Improved energy utilization might be one explanation. Using indirect calorimetry, phytase-induced changes in energy metabolism were evaluated in young piglets with adequate phosphorus intake. Eight replicates of 8 group-housed barrows each were assigned to either a control or a phytase-supplemented diet [1500 phytase units (FTU)/kg feed]. Piglets were fed a restricted amount of the control or phytase diet. The diets were made limiting in energy content by formulating them to a high digestible lysine:DE ratio. Fecal nutrient digestibility, portal blood variables, organ weights, and apparent absorption and urinary excretion of ash, Ca, P, Na, K, Mg, Cu, and Fe, were also measured. A model was developed to estimate energy required for absorption and excretion, which are partly active processes. Phytase tended to improve energy digestibility (P = 0.10), but not its metabolizability. Energy retention and heat production were not affected. At the end of the 3-wk period, pancreas weight (P < 0.05) and blood pH were lower (P < 0.01), and CO(2) pressure was higher (P < 0.01) due to phytase. This suggests that phytase reduced energy expenditure of the digestive tract, and increased metabolic activity in visceral organs. The potential increases in energy retention due to phytase were counterbalanced by increased energy expenditures for processes such as increased mineral absorption (for most P < 0.05), and their subsequent urinary excretion. Energy costs of increased absorption of nutrients, and deposition and excretion of minerals was estimated as 4.6 kJ/(kg(0.75) . d), which is 1% of the energy required for maintenance. The simultaneous existence of both increases and decreases in heat production processes resulted in the absence of a net effect on energy retention.
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PMID:Mineral absorption and excretion as affected by microbial phytase, and their effect on energy metabolism in young piglets. 1586 93

An experiment was conducted to determine the efficacy of a so-called consensus phytase preparation produced by Hansenula polymorpha on growth, tibia and toe ash and P retention of young turkeys. A total of 192 female turkeys (BUT 9 strain) were placed into 96 batteries at two per cage and assigned to one of eight diets: A negative control containing 2.5 g non-phytate P per kg feed (T-1); T-1 plus 125, 250, 500, 1000 or 10 000 phytase units (U) per kg feed, respectively, (T-2 to T-6); T-1 plus 0.5 or 1.0 g Pi/kg feed as dicalcium phosphate dihydrate (DCP), respectively, (T-7 and 8). The experiment lasted 32 d, and excreta were collected and weighed between 26 and 29 d of age. Feed was also weighed during this period in order to calculate P retention. Performance was calculated for the 0 to 32 d period. At the end of the experiment one bird per pen was killed for tibia and toe ash content determination, except for T-2, T-3, and T-7. Body weight, FCR, toe and tibia ash, and P retention responded to phytase or Pi supplementation. Using linear or quadratic models for comparing performance of the treatments containing supplemental Pi with phytase treatments, an equivalence between phytase and Pi was calculated. Body weight, toe ash, tibia ash and P retention showed a significant response to phytase supplementation. The values of equivalence for body weight, toe ash, tibia ash and P retention were 251, 597, 391 and 390 U to 1 g Pi/kg feed. At 10 000 U/kg feed there was a significant response in terms of weight gain and P retention, indicating that turkeys respond to levels greater than 1 000 U/kg feed.
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PMID:Phosphorus equivalence of a Consensus phytase produced by Hansenula polymorpha in diets for young turkeys. 1588 52

An experiment was conducted to determine the interactive effects of Eimeria acervulina infection and phytase in male broiler chicks. Chicks were standardized from 0 to 4 d posthatching, and the assay period was 5 to 15 d. Treatments were replicated with 6 pens of 5 chicks each. The initial and final BW were 67 and 363 g. A corn-soybean meal diet formulated to provide 1.26% total Lys and 3,200 kcal of ME/kg was used, and it was adequate in all other nutrients except Ca and nonphytate P (NPP) when appropriate. The treatments were in a 2 x 2 x 2 factorial arrangement: adequate Ca and NPP (1.0% Ca and 0.45% NPP) or inadequate Ca and NPP (0.80% Ca and 0.25% NPP), 0 or 600 phytase units/kg of diet, and uninfected or infected with 400,000 E. acervulina oocysts on d 0, 3, and 6 of the experiment. Daily gain, average daily feed intake, and gain:feed (GF) were reduced (P < 0.01) by the coccidial infection and the reduction in Ca and NPP. Phytase addition increased (P < 0.02) average daily gain and average daily feed intake, regardless of the Ca and NPP contents of the diet or the presence of coccidiosis. The GF was increased by phytase but only in uninfected chicks (phytase x coccidiosis, P < 0.02). Toe and tibia ash percentages were decreased (P < 0.01) in chicks fed diets deficient in Ca and NPP, but tibia ash was decreased more by Ca and NPP in healthy chicks than in infected chicks (coccidiosis x Ca and NPP, P < 0.02). Phytase increased (P < 0.02) toe and tibia ash but only in diets deficient in Ca and NPP (phytase x Ca and NPP, P < 0.01). Phytase increased toe ash percentage of healthy chicks fed diets deficient in Ca and NPP, but it had less of an effect in infected chicks fed diets deficient in Ca and NPP (coccidiosis x Ca and NPP x phytase, P < 0.08). Also, phytase was less effective in increasing tibia ash percentage in coccidiosis-infected chicks than in uninfected chicks (phytase x coccidiosis, P < 0.02). These data indicate that phytase is effective in the presence of a coccidial infection, but based on GF and tibia ash percentage, it may not be as effective as in uninfected chicks. Also, phytase increased average daily gain and average daily feed intake in uninfected chicks fed diets formulated to be adequate (or in excess) in all nutrients for male broiler chicks.
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PMID:The interactive effects of Eimeria acervulina infection and phytase for broiler chicks. 1597 29

Corn-soybean meal-based diets, consisting of a high-P control (HPC) containing supplemental dicalcium phosphate (DCP), a basal diet containing no DCP, and the basal diet plus Escherichia coli phytase at 500 or 1,000 phytase units per kilogram (FTU/kg; as-fed basis) were fed to evaluate growth performance in starter, grower, and finisher pigs. Pigs were blocked by weight and gender, such that average weight across treatments was similar, with equal numbers of barrows and gilts receiving each treatment in each block. In Exp. 1, 48 pigs with an average initial BW of 11 kg, housed individually, with 12 pens per diet, were used to evaluate growth performance over 3 wk. Overall ADG and G:F were increased linearly (P < 0.05) by dietary phytase addition. Final BW and plasma P concentrations at 3 wk also increased linearly (P < 0.05). In Exp. 2, 128 pigs with an average initial BW of 23 kg, housed four pigs per pen, with eight pens per diet, were used to evaluate growth performance over 6 wk. A linear increase in response to phytase was noted for ADG and G:F in all three 2-wk periods, as well as overall (P < 0.05). Percentage of bone ash also showed a linear increase (P < 0.01). In Exp. 3, 160 pigs (53 kg), housed five pigs per pen, with eight pens per diet, were used to evaluate growth performance over 6 wk. A linear increase was detected for final BW, as well as ADG and G:F in the first and second 2-wk periods, and overall (P < 0.01). Twenty-four 15-kg individually housed pigs were used to evaluate total-tract nutrient digestibility in Exp. 4. Daily absorption of P linearly increased (P < 0.05) with phytase supplementation. Results of this research indicate that E. coli phytase is effective in liberating phytate P for uptake and utilization by starter, grower, and finisher pigs.
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PMID:Escherichia coli phytase improves growth performance of starter, grower, and finisher pigs fed phosphorus-deficient diets. 1602 8

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).
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PMID: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. 1605 Jan 88

1. An experiment with 150 White Leghorn layers was conducted to examine the effect of microbial phytase supplementation of low non-phytate phosphorus (NPP) diets on egg production, eggshell quality, bone mineralisation and retention of nutrients at 32-48 weeks of age. 2. Four isonitrogenous and isocaloric diets were formulated to contain 1.2, 1.8, 2.4 and 3.0 g NPP/kg diet with the two lowest NPP (1.2 and 1.8) supplemented with microbial phytase (Biofeed Phytase, India) at 500 FTU per kg diet. Each diet was offered ad libitum to 5 replicates of 5 layers throughout the experiment. 3. Body weight gain was reduced significantly in the layers fed on the 1.2 g/kg NPP diet as compared to those given diets containing 1.8-3.0 g/kg. Addition of phytase to the 1.2 g/kg diet significantly enhanced the body weight and was comparable with those given diets containing 1.8-3.0 g/kg NPP. 4. No additional advantage resulted from enhancing the NPP levels beyond 1.8 g/kg or adding phytase to a diet containing 1.8 g/kg NPP. 5. Hen d egg production, food intake, food efficiency, shell weight, shell thickness, shell strength and tibia strength followed the same trends as above. However, adding phytase to the 1.8 g/kg NPP diet significantly enhanced tibia ash. Egg weight, specific gravity and Haugh units were influenced by neither NPP concentration nor phytase supplementation. 6. Adding phytase to the 1.2 g/kg NPP diet significantly enhanced nitrogen and phosphorus retention. 7. It was concluded that addition of 500 FTU of microbial phytase/kg diet can allow the reduction of NPP content to 1.2g/kg in the layer diet, eliminate inorganic phosphorus supplementation and results in significant reduction of nitrogen and phosphorus excretion without affecting the production performance of layers.
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PMID:Effect of microbial phytase on production performance of White Leghorn layers fed on a diet low in non-phytate phosphorus. 1626 4

1. Growth performance, serum bone markers, and bone strength and mineralisation were determined in tom turkeys grown from 9 to 17 weeks of age. 2. Dietary non-phytate phosphorus was formulated to be reduced by 1.0 g/kg in the low phosphorus diet compared to a control diet and phytase was added to provide 0, 150, 300, 450 or 600 units/kg activity to the low phosphorus diet. 3. From 9 to 12 weeks of age, body weight and gain:food were reduced by the low phosphorus diet without added phytase, compared to the adequate phosphorus diet. Increasing the concentration of phytase linearly increased these growth parameters. There were no significant growth responses at 17 weeks of age. 4. Serum osteocalcin was reduced by increasing dietary phosphorus at 12 weeks of age when growth was affected, but not at later ages. Serum pyridinoline was reduced by higher dietary phosphorus and decreased linearly with increasing phytase activity at 17 weeks of age. 5. Fracture force of the ulna and femur increased linearly with increasing phytase activity but bone strength was not affected when corrected for bone cross-sectional area. Bone strength of the ulna and ash concentration of the ulna and tibia were increased by higher dietary phosphorus. Humerus and ulna ash increased linearly with increasing phytase activity. 6. Water-soluble phosphorus content of the litter was increased by higher dietary phosphorus and addition of phytase to the low phosphorus diet. The increase in water-soluble phosphorus content of the litter when phytase was fed may indicate that phosphorus could be fed at a lower concentration than used in this trial, at least in the finisher diet when phytase is added to the food. 7. Bone fracture force, strength and ash were generally optimised when 450 units/kg phytase activity was added to the low phosphorus diet. However, growth performance was best in the grower I (9 to 12 weeks) phase when 600 units/kg phytase was added to the diet.
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PMID:Evaluation of phytase concentration needed for growing-finishing commercial turkey toms. 1626 5

Supplemental 1alpha-hydroxycholecalciferol (1alpha-OHD3) has been shown to have qualitatively similar and quantitatively additive effects to exogenous phytase. Two experiments were conducted from 0 to 35 d in floor pens to determine the additive effect of phytase and 1alpha-OHD3 when supplemented to Ca- and P-deficient diets. In both experiments, at least 4 replicates per treatment (50 chicks per replicate) were used. Corn-soybean-meal-and soybean-oil-based diets were fed and birds were raised in a house impervious to ultraviolet light. During the starter phase (ST), from 0 to 18 d, chicks were fed a 23% CP diet containing 0.60% Ca and 0.47% total P (tP). During the grower/finisher phase (GF), from 19 to 35 d, birds were fed a 19% CP diet containing 0.30% Ca and 0.37% tP. A combination of 1,000 phytase units/kg of Natuphos phytase and 5 microg/kg of 1alpha-OHD3 (P+1A) was supplemented to some of the feed during the ST and GF. Diets containing adequate Ca and P were also fed during the ST (0.90% Ca, 0.68% tP) and GF (0.80% Ca, 0.67% tP). Performance characteristics and the incidence of rickets and tibial dyschondroplasia were measured at 18 and 35 d. In experiment 1, unsupplemented chicks performed well but had considerable leg problems. Chicks fed P+1A during the ST or GF did not perform as well as birds fed P+1A throughout. Birds fed P+1A throughout performed as well birds fed the adequate diets without any indication of leg problems. In experiment 2, unsupplemented birds performed similarly to unsupplemented birds in experiment 1. However, chicks fed the supplements or the control diets did not perform as well or accumulate as much bone ash as birds in experiment 1, although the diets were formulated identically in both experiments. Diets with as little as 0.30% Ca and 0.37% tP appear to be adequate for broilers older than 18 d if supplemented with the correct amounts of phytase and 1alpha-OHD3. However, there are unknown variables that may limit the potential of broilers in terms of bone mineralization and bone pathology, even when adequate diets are fed.
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PMID:Phytase and 1alpha-hydroxycholecalciferol supplementation of broiler chickens during the starting and growing/finishing phases. 1633 32

Three experiments were conducted to evaluate the effectiveness of OptiPhos phytase and citric acid for releasing the P that is not bioavailable in distillers dried grains with solubles (DDGS). The effect of OptiPhos phytate on AME(n) and amino acid digestibility was also determined. New Hampshire x Columbian chicks were fed experimental diets from 8 to 21 d of age. For Experiment 1, a basal P-deficient diet contained 40% DDGS plus supplemental amino acids, and DDGS was the only source of P. The basal diet was then supplemented with 1,000 or 10,000 phytase units (FTU)/kg of OptiPhos phytase or with 0.2% of P from KH2PO4. In Experiment 2, a slope-ratio chick growth and tibia ash assay used a P-deficient soybean meal basal diet, and it was found that the bioavailability of P in DDGS was 67%. For Experiment 3, a P-deficient basal diet with 30% DDGS plus supplemental amino acids was supplemented with 0.05 or 0.1% P from KH2PO4, with 3% citric acid, or with 1,000 or 10,000 FTU/kg of OptiPhos phytase. In Experiment 1, both 1,000 and 10,000 FTU/kg of phytase increased tibia ash but had no effect on AME(n). Both 10,000 phytase units (FTU)/kg of phytase and supplemental P increased digestibility of amino acids. In Experiment 3, supplemental phytase and citric acid increased tibia ash (mg/tibia), and it was estimated that phytase and citric acid could release from 0.04 to 0.07% P from DDGS. In terms of bioavailability coefficients, the bioavailability of the P in DDGS was increased from 62 to 72%. These results indicate that phytase and citric acid increase the bioavailability of P in DDGS, but phytase at 1,000 FTU/kg had no consistent effect on AME(n) and amino acid digestibility.
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PMID:Effect of microbial phytase and citric acid on phosphorus bioavailability, apparent metabolizable energy, and amino acid digestibility in distillers dried grains with solubles in chicks. 1655 78

Five experiments (Exp.) were conducted to determine the effects of phytase on growth performance and intestinal transit time in chicks fed nutritionally adequate diets and diets deficient in Ca and nonphytate P (nPP). In Exp. 1 and 2, chicks were fed a nutritionally adequate diet from 0 to 6 d or from 0 to 4 d posthatching; assay periods were 8 or 10 d; average initial BW were 98 or 79 g; and average final BW were 371 or 369 g, respectively. Treatments were replicated with 12 pens of 5 chicks each. Corn-soybean meal (C-SBM) diets were adequate in all nutrients except Ca and nPP where appropriate. The treatments were 1) C-SBM, 1.0% Ca, and 0.45% nPP; 2) C-SBM, 0.80% Ca, and 0.25% nPP; 3) Diet 1 + 600 phytase units/kg of diet; 4) Diet 2 + 600 phytase units/kg of diet. Experiments 3, 4, and 5 were conducted to determine the effects of phytase on intestinal transit time in broilers. Broilers were fed the same nutritionally adequate diet from 0 to 18, 27, or 23 d posthatching, and the assay periods were 7 d. Treatments were replicated with 18 individually penned broilers. Average initial BW were 768, 1,108, or 838 g, and average final BW were 1,299, 1,704, or 1,392 g in Exp. 3 to 5, respectively. Transit time data were collected on d 1 and 7 of the Exp. Diets were 1) C-SBM, 0.9% Ca, and 0.35% nPP; 2) C-SBM, 0.80% Ca, and 0.25% nPP + 600 phytase units/kg of diet. Transit time was calculated as the difference between the time feed was first ingested and the time of first appearance of solid feces. In Exp. 1 and 2, the reduction in dietary Ca and nPP reduced (P < 0.01) average daily gain (ADG), average daily feed intake (ADFI), and gain:feed. Phytase addition increased (P < 0.02) ADG and ADFI in diets deficient in Ca and nPP and in the nutritionally adequate diets. In Exp. 2, the reduction in Ca and nPP reduced (P < 0.01) toe and tibia ash percentage, but phytase addition increased (P < 0.01) toe and tibia ash percentage. The increase in toe ash percentage was greater in chicks fed the Ca and nPP deficient diet than in chicks fed the nutritionally adequate diet (Ca and nPP x phytase, P < 0.01). In Exp. 3, 4, and 5, transit time on d 1 was faster (P < 0.03) in chicks fed phytase. On d 7, transit time tended to be faster in chicks fed phytase, but the effect was not significant (P = 0.15). These data indicate that phytase increases ADG and ADFI in diets deficient in Ca and nPP and in diets formulated to be adequate (or excess) in all nutrients for broiler chicks. The increase in ADG and ADFI in chicks fed the nutritionally adequate diet may be due to a faster transit time of feed through the digestive tract, resulting in a greater feed intake and gain.
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PMID:The effects of phytase on growth performance and intestinal transit time of broilers fed nutritionally adequate diets and diets deficient in calcium and phosphorus. 1655 81


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