Phytate Phosphorus Hydrolysis Research Articles

Treatment of grain with organic acids at 2 different dietary phosphorus levels modulates ruminal microbial community structure and fermentation patterns in vitro

Recent data indicate positive effects of treating grain with citric (CAc) or lactic acid (LAc) on the hydrolysis of phytate phosphorus (P) and fermentation products of the grain. This study used a semicontinuous rumen simulation technique to evaluate the effects of processing of barley with 50.25g/L (wt/vol) CAc or 76.25g/L LAc on microbial composition, metabolic fermentation profile, and nutrient degradation at low or high dietary P supply. The low P diet [3.1g of P per kg of dry matter (DM) of dietary P sources only] was not supplemented with inorganic P, whereas the high P diet was supplemented with 0.5g of inorganic P per kg of DM through mineral premix and 870mg of inorganic P/d per incubation fermenter via artificial saliva. Target microbes were determined using quantitative PCR. Data showed depression of total bacteria but not of total protozoa or short-chain fatty acid (SCFA) concentration with the low P diet. In addition, the low P diet lowered the relative abundance of Ruminococcus albus and decreased neutral detergent fiber (NDF) degradation and acetate proportion, but increased the abundance of several predominantly noncellulolytic bacterial species and anaerobic fungi. Treatment of grain with LAc increased the abundance of total bacteria in the low P diet only, and this effect was associated with a greater concentration of SCFA in the ruminal fluid. Interestingly, in the low P diet, CAc treatment of barley increased the most prevalent bacterial group, the genus Prevotella, in ruminal fluid and increased NDF degradation to the same extent as did inorganic P supplementation in the high P diet. Treatment with either CAc or LAc lowered the abundance of Megasphaera elsdenii but only in the low P diet. On the other hand, CAc treatment increased the proportion of acetate in the low P diet, whereas LAc treatment decreased this variable at both dietary P levels. The propionate proportion was significantly increased by LAc at both P levels, whereas butyrate increased only with the low P diet. Treatments with CAc or LAc reduced the degradation of CP and ammonia concentration compared with the control diet at both P levels. In conclusion, the beneficial effects of CAc and LAc treatment on specific ruminal microbes, fermentation profile, and fiber degradation in the low P diet suggest the potential for the treatment to compensate for the lack of inorganic P supplementation in vitro. Further research is warranted to determine the extent to which the treatment can alleviate the shortage of inorganic P supplementation under in vivo conditions.

Short Communication: An insight into protein sequences of PTPlike cysteine phytases

Abstract. Kumar V, Agrawal S. 2014. An insight into protein sequences of PTP-like cysteine phytases. Nusantara Bioscience 6: 102-106. Protein tyrosine phosphatase-like cysteine phytases (CPhy) are novel phytases reported in the ruminant microbial community and suggested to play major role in phytate-phosphorus hydrolysis in animal feed. These phytases are very promising to be used in animal feed applications for monogastric animals. Present study deals with utilization of sequence information of 40 CPhy reference protein sequences for their sequential characterization for conserved regions, phylogenetic relationship, biochemical features, superfamily and functional motifs therein. The study reveals that CPhy, not well-characterized class of phytases, contains conserved sequence feature which may be important catalytic residues. Five major clusters observed in phylogenetic tree with Clostridium sp. as largest cluster. Reported motifs might be used for diversity and expression analysis of CPhy enzymes.

Effect of maize endosperm hardness, drying temperature and microbial enzyme supplementation on the performance of broiler chickens

This study was conducted to determine the influence of maize endosperm type (soft or vitreous), drying temperature (60, 100, 140°C), and enzyme addition (no enzyme or phytase + xylanase) on broiler chicken growth, amino acid availability, and phytate phosphorus hydrolysis. One-day-old Ross-308 broiler chicks (total 1200) were allotted to floor pens with a randomised complete block design (2 × 3 × 2). Diets were formulated to be marginally deficient in Lys, total sulfur amino acids, calcium, and nonphytate phosphorus. A positive effect (P < 0.05) of enzyme addition on chicken bodyweight gain to day 35 was observed (1884 vs 1940 g). Bodyweight gains and feed conversion ratios (FCR) were linearly depressed when drying temperature was increased. Chickens fed vitreous maize were characterised by lower bodyweight gain (1932 vs 1893 g; P < 0.05) and higher FCR (1.796 vs 1.840g : g; P < 0.05). There were no interactions between any of the main effects for overall performance metrics. The use of phytase improved phytic acid digestibility (0.302 vs 0.389; P < 0.05) but phytic acid digestibility was unaffected (P > 0.05) by drying temperature or hardness. The highest drying temperature had a negative effect on amino acids digestibility (P < 0.05). The use of phytase and xylanase improved amino acid apparent ileal digestibility (P < 0.05), except for Cys, Met, and Phe. Results from this study show that drying temperature and vitreousness of maize influence the nutritional value of this grain for broilers. Part of the beneficial effect of the addition of phytase + xylanase to diets with overheated maize for poultry appears to be mediated through an improvement in amino acid availability.

Phytate Phosphorus Hydrolysis in Broilers in Response to Dietary Phytase, Calcium, and Phosphorus Concentrations

Three 5-d bioassays were conducted to investigate the microbial phytase effect on apparent phytate phosphorus (PP) hydrolysis by 21-d-old broilers using corn-soybean meal basal diets. In Experiment 1, broilers fed corn-soy basal diet [0.7% Ca, 0.4% total P (TP), and 0.12% nonphytate P (NPP)] with 0, 250, 500, 750, 1,000, 1,500, 2,000, and 5,000 FTU of phytase/kg diet produced PP hydrolysis (%) of 43.12, 68.12, 74.7, 85.02, 85.25 92.77, 96.91, and 99.45, respectively. In Experiment 2, broilers fed corn-soy basal (0.5% Ca and 0.17% PP) without added phytase and 0.08, 0.13, 0.18, 0.23, 0.28, 0.33, 0.38, and 0.45% NPP had PP hydrolysis (%) of 8.5, 27.6, 26.4, 28.9, 26.3, 17.1, 21.0, and 27.7, respectively. Broilers fed the same 0.5% Ca basal and NPP concentrations with 1,000 FTU of phytase/kg of diet increased (P < 0.05) PP hydrolysis (%) to 80.9, 75.9, 73.5, 72.2, 68.4, 71.6, 58.3, and 62.5, respectively. Experiment 3 was conducted in the same way as Experiment 2 but Ca was maintained at 0.9% for all diets. Phytate P hydrolysis (%) without addition of phytase in 0.08, 0.13, 0.18, 0.23, 0.28, 0.33, 0.38, and 0.45% NPP-fed groups was 49.2, 19.6, 16.0, 8.0, 9.4, 2.1, 4.0, and 4.2, respectively. The addition of phytase increased (P < 0.05) PP hydrolysis (%) to 85.3, 76.1, 70.0, 76.1, 62.6, 68.6, 67.4, and 63.7, respectively. In conclusion, these studies indicated near-complete hydrolysis (99.45%) of PP at greater dietary phytase (5,000 FTU/kg) supplementation, but maximum TP retention was obtained with only 1,000 FTU of added phytase. Maximum PP hydrolysis occurred for broilers fed diets with 1,000 FTU added phytase when the diets contained the lowest concentration (0.08%) of dietary NPP with either 0.5 or 0.9% dietary Ca concentrations. These data also suggest that broilers fed 0.9% dietary Ca have a greater P physiological threshold before a loss in retention compared with broilers fed lower (0.5%) dietary Ca concentrations with no dietary phytase supplementation.

The Effect of Several Organic Acids on Phytate Phosphorus Hydrolysis in Broiler Chicks

Supplementation of some organic acids to a P-deficient diet has been shown to improve phytate P utilization. Two experiments were conducted from 0 to 16 d in battery brooders to determine the effect of various organic acids supplementation on phytate P utilization. In both experiments, birds were fed P-deficient corn and soybean meal-based diets. In experiment 1, citric acid, malic acid, fumaric acid, and EDTA were supplemented. Experiment 2 had a 2 x 2 factorial design with 2 sources of Met, 2-hydroxy-4-(methylthio) butanoic acid (HMB) and dl-Met, with or without 500 U/kg of phytase. In experiment 1, the addition of citric, malic, and fumaric acids increased percentage of bone ash, but only the effect of citric acid was significant. The addition of citric and malic acids also significantly increased the retention of P and phytate P (P<0.05). In experiment 2, the addition of phytase to the diet significantly increased 16-d BW gain, feed intake, percentage of bone ash, milligrams of bone ash, phytate P disappearance, and decreased the incidence of P-deficiency rickets. Methionine source did not affect 16-d BW gain, feed intake, feed efficiency, milligrams of bone ash, or P rickets incidence. However, the birds fed HMB had a higher percentage of bone ash and phytate P disappearance compared with the groups fed dl-Met only when phytase was added to the diets. The additions of citric acid and HMB improved phytate P utilization. However, the reason why some organic acids are effective whereas others are not is not apparent.

A highly pH-stable phytase from Yersinia kristeensenii: Cloning, expression, and characterization

The gene appA, encoding a phytase from Yersinia kristeensenii, was cloned and heterologously expressed in Pichia pastoris. The open reading frame of appA comprised 1326 bp encoding a protein of 441 amino acids including a 24-amino acid signal peptide. The encoded phytase, APPA, was 87% identical to the phytase from Y. intermedia but was <52% identical to other histidine acid phosphatases. The purified recombinant phytase had an optimal activity at 55 °C and pH 4.5, and it exhibited enzymatic activity between pH 2.0 and 6.5, with a specific activity of 2656 U mg −1 at pH 4.5 and 37 °C. r-APPA retained more than 90% of its initial activity after being incubated under varying pH conditions (pH 1.5–11.0) at 37 °C for 3 h. r-APPA was resistant to heat inactivation, as it retained 46% of its initial activity after incubation at 80 °C for 10 min. r-APPA was effective for the hydrolysis of phytate phosphorus from soybean meal in vitro. Comparison of r-APPA with other well-known phytases suggests that the Y. kristeensenii phytase would be an attractive enzyme for feed industry use.

Effects of Copper Source and Concentration on in Vitro Phytate Phosphorus Hydrolysis by Phytase

Five copper (Cu) sources were studied at pH 2.5, 5.5, and 6.5 to determine how Cu affects phytate phosphorus (PP) hydrolysis by phytase at concentrations up to 500 mg/kg diet (60 min, 40-41 degrees C). Subsequently, Cu solubility with and without sodium phytate was measured. Adding Cu inhibited PP hydrolysis at pH 5.5 and pH 6.5 (P < 0.05). This inhibition was greater with higher concentrations of Cu. Tri-basic copper chloride and copper lysinate inhibited PP hydrolysis much less than copper sulfate pentahydrate, copper chloride, and copper citrate (P < 0.05). A strong negative relationship was observed between PP hydrolysis and soluble Cu at pH 5.5 (r = -0.76, P < 0.0001) and 6.5 (r = -0.54, P < 0.0001). In conclusion, pH, Cu concentration, and source influenced PP hydrolysis by phytase in vitro and were related to the amount of soluble Cu and the formation of insoluble copper-phytin complexes.

Effect of dietary calcium and vitamin D3 on calcium and phosphorus retention in white Pekin ducklings

Higher concentrations of Ca in the diet may decrease phytate-phosphorus hydrolysis because of chelation of Ca with the phytin molecule. In experiment 1, drakes were fed 0.74, 0.85, 0.95, or 1.11% Ca (analyzed) from 7 to 18 d of age (6 birds/cage, 8 cages/diet). Intestinal mucosa was collected at 18 d of age from birds fed 0.74 and 1.11% Ca for determination of intestinal phytase activity. In experiment 1, 17 d BW gain and feed consumption exhibited a quadratic response to increasing concentrations of Ca and were found to be maximal for ducks fed the 0.95% Ca diet. Toe ash percentage (18 d) had a quadratic response to increasing concentrations of Ca with a maximal response for birds fed the 0.85% Ca diet. Increasing dietary Ca did not affect P retention from 15 to 17 d of age or intestinal phytase activity and brush border vesicle Ca concentration. A positive correlation was found between the Vmax and the Ca concentration within the vesicles (r = 0.59, P < 0.02), suggesting that the vesicle Ca concentration did not negatively affect the kinetics of the phytase assay. In experiment 2, drakes were fed 0.6, 0.8, 1.0, or 1.2% Ca (formulated) with 826 or 8,260 ICU/kg of vitamin D3 from 0 to 13 d of age. There was no response to increasing concentrations of Ca for performance characteristics or bone ash measurements.

Evaluation of a Microbial Phytase, Produced by Solid State Fermentation, in Broiler Diets II. Influence on Phytate Hydrolysis, Apparent Metabolizable Energy, and Nutrient Utilization

The influence of a microbial phytase, produced by solid-state fermentation, on phytate phosphorus (PP) hydrolysis, AMEn, and nutrient utilization of male and female broilers fed a wheat-soy-canola diet was examined. Ileal phytate hydrolysis data provided direct evidence to the efficacy of phytase in hydrolyzing the phytic acid. Addition of 500 phytase units (PU)/kg to the wheat-soy-canola diet containing 0.28% PP increased the PP hydrolysis from 28.0 to 59.3% and from 27.2 to 51.9% in male and female broilers, respectively. Increased PP release resulted in corresponding improvements in apparent ileal digestibility and retention of phosphorus and lowered excreta phosphorus contents. Excreta phosphorus contents in birds fed the low phosphorus plus 500 PU/kg were 35% lower than those in birds fed the adequate phosphorus diet, during both starter and finisher phases. Phytase supplementation caused improvements in apparent ileal nitrogen digestibility, nitrogen retention, and AMEn. The overall responses observed with phytase supplementation may be partly reflective of the side enzyme activities present in this product and suggest that enzyme products with multiple enzymes may provide a competitive strategy to improve the nutrient utilization of wheat-based poultry diets.

Influence of dietary calcium and phytase on phytate phosphorus hydrolysis in broiler chickens

The effect of Ca and phytase on phytate phosphorus (PP) hydrolysis was studied in vitro and in vivo. In vitro, PP hydrolysis by a 3-phytase and a 6-phytase was studied at pH 2.5 and 6.5 with Ca added at levels equivalent to 0, 0.1, 0.2, 0.4, 0.7, or 0.9% of the diet. Irrespective of enzyme, Ca at a level as low as 0.1% reduced (P < 0.05) PP hydrolysis at pH 6.5. To test these effects in vivo, 22-d-old male broilers were fed 1 of 6 diets (10 replicate pens of 4 birds per diet) for 30 h. The experimental design was a 3 × 2 factorial arrangement of 3 phytase treatments (0, 500 U of phytase A/kg of diet, and 500 U of phytase B/kg of diet) and 2 added Ca levels (0 and 0.5% from CaCO3) to a corn-soy basal diet. Adding Ca to the diet resulted in a reduction (P < 0.05) in ileal PP disappearance from 69.2 to 25.4% when the 0 and 0.5% added Ca diets were fed, respectively, and in apparent ileal Ca and P absorption (46.3 to 33.6% and 67.9 to 29.4% when 0 and 0.5% Ca were added, respectively). Inclusion of a 3-phytase improved (P < 0.05) ileal PP disappearance from 25.4 to 58.9% in diets containing 0 and 0.5% added Ca, but the improvement was less pronounced with a 6-phytase. Apparent ileal Ca absorption was improved (P < 0.05) when Ca, phytase, or both were added to the diet.

Phytate phosphorus hydrolysis as influenced by dietary calcium and micro-mineral source in broiler diets.

Phytate phosphorus (PP) hydrolysis by a 3-phytase was studied in vitro at pH 2.5 and 6.5 with either 0, 1.0, 4.0, or 9.0 g of Ca/kg diet, or 0, 1.0, 5.0, 7.5, or 10.0 g/kg diet of micro-mineral premix added as inorganic (IMM) or an equivalent level as micro-mineral-amino acid complexes (MAAC). Adding Ca or micro-minerals reduced (P < 0.05) PP hydrolysis at both pHs; however, the effect was greater at pH 6.5. An in vivo experiment was conducted in which broilers were fed one of six diets for 30 h. The experimental design was a factorial of three micro-mineral forms (0 added, IMM, and MAAC) and two Ca levels (0 or 5 g/kg). Adding Ca reduced (P < 0.05) PP disappearance and increased Ca apparent absorption. No micro-minerals effect (P > 0.05) was seen. Therefore, in poultry diets, it is Ca that inhibits PP hydrolysis and decreases P availability.

Effect of dietary calcium, 25-hydroxycholecalciferol, or bird strain on small intestinal phytase activity in broiler chickens

Broilers chickens have limited ability to utilize phytate phosphorus (PP), and the influence of nutrients on the activity and efficacy of intestinal phytase is unclear. Therefore in a 2 × 2 × 2 factorial experiment, male chicks were fed 0 or 0.21 mg/kg 25-hydroxycholecalciferol (25-OH D3), 4 or 9 g/kg Ca supplied from CaCO3 or Ca malate from 14 to 24 d of age (six pens/treatment, eight birds/pen). Source of Ca had no effect on tibia ash, intestinal phytase activity, or apparent ileal PP hydrolysis. Phytase activity (Vmax) within brush border vesicles prepared from small intestinal mucosa was greater in chicks fed 4 vs. 9 g/kg Ca (P < or = 0.05). Similarly, birds fed 4 vs. 9 g/kg Ca were able to hydrolyze an additional 24.36% PP (P < 0.01). Intestinal phytase activity and apparent ileal PP hydrolysis were not affected by 25-OH D3 supplementation, but tibia ash was improved by 2.7% (P < 0.01). A subsequent experiment validated the effect of dietary Ca (4 and 9 g/kg) and elucidated differences between strains (Ross 308 and Hubbard × Peterson) from 8 to 22 d of age (six pens/treatment, eight birds/pen). The strains responded similarly to dietary Ca in terms of intestinal phytase and apparent ileal PP hydrolysis. Intestinal phytase activity was 9% greater in birds fed 4 vs. 9 g/kg Ca (P < 0.05) and apparent ileal PP hydrolysis was 11.9% greater (P < 0.02). In conclusion, a typical dietary Ca concentration (9 g/kg) reduced intestinal phytase activity and apparent ileal PP hydrolysis.

A bioassay to determine the effect of phytase on phytate phosphorus hydrolysis and total phosphorus retention of feed ingredients as determined with broilers and laying hens

In order to accurately formulate diets for broilers and laying hens to meet phosphorus requirements without overfeeding, precise knowledge of an individual feed ingredient's contribution to the retainable phosphorus is needed. Seven feed ingredients, included as the sole source of phosphorus, were tested with and without the addition of 600 phytase units (FTU) phytase/kg diet, in a 5-d bioassay with 10 22-d-old male broilers. Without addition of phytase, the amounts of phytate phosphorus hydrolyzed in corn, soybean meal, wheat, wheat midds, barley, defatted rice bran, and canola were 30.8, 34.9, 30.7, 29.1, 32.2, 33.2, and 36.7%, respectively. The addition of phytase increased (P < or = 0.05) each value to 59.0, 72.4, 46.8, 52.2, 71.3, 48.0, and 55.8%, respectively. The addition of phytase increased total phosphorus retention from 34.8, 27.0, 16.0, 31.9, 40.3, 15.5, and 39.4% to 40.9, 58.0, 33.8, 43.4, 55.5, 26.5, and 45.7%, respectively. A similar bioassay was conducted with laying hens fed corn, soybean meal, and defatted rice bran. Without phytase addition, phytate phosphorus hydrolyzed in soybean meal, corn, and rice bran was determined to be 25.7, 23.0, and 36.1%, respectively, and was increased (P < or = 0.05) to 62.4, 52.0, and 50.9%, respectively, with the addition of 300 FTU phytase/kg feed. Total phosphorus retention of soybean meal, corn, and rice bran increased from 36.8, 28.6, and 35.9% to 53.4, 44.7, and 43.0%, respectively, with the addition of phytase.

Different Sensitivity of RecombinantAspergillus nigerPhytase (r-PhyA) andEscherichia colipH 2.5 Acid Phosphatase (r-AppA) to Trypsin and Pepsinin Vitro

Proteolysis of two purified recombinant enzymes, namely, theAspergillus nigerphytase (r-PhyA) and theEscherichia colipH 2.5 acid phosphatase (r-AppA), by pepsin and trypsin was investigated in this study. After r-PhyA and r-AppA were incubated with different concentrations of pepsin or trypsin, their residual phytase activities and amounts of inorganic phosphorus released from soybean meal were determined. Both enzymes retained more than 85% of their original activities at the trypsin/phytase ratios (w/w) 0.001 and 0.005, while r-AppA and r-PhyA lost 60 and 20% of the original activity at the ratio of 0.01 or 0.025, respectively. In contrast, there was a 30% increase in phytase activity after r-AppA was incubated with pepsin at the ratios of 0.005 or 0.01. Meanwhile, r-PhyA lost 58 to 77% of its original activity under the same conditions. Trypsin and pepsin affected the hydrolysis of phytate phosphorus from soybean meal by r-AppA and r-PhyA in a similar way to their residual phytase activities. All of thesein vitroproteolyses were confirmed by SDS–PAGE analysis. Our results demonstrate different sensitivities of r-AppA and r-PhyA to trypsin and pepsin, suggesting active trypsin resistant r-PhyA and pepsin resistant r-AppA polypeptides.

Dephosphorylation of phytate compounds by means of acid phosphatase from Aspergillus niger

AbstractA non‐purified preparation of intracellular acid phosphatase (EC 3.1.3.2) from a waste mycelium of Aspergillus niger was utilised for dephosphorylation of phytate compounds present in food and feed ingredients. The enzymic hydrolysis of p‐nitrophenylphosphate was used for assaying acid phosphatase activity, expressed in standard units (u).The hydrolysis of phytate phosphorus in wheat bran, soya bean meal and fully formulated feedstuffs for broilers (Galus galus; ‘Cornish’ × White Rock') was carried out at 40°C, a pH value of 4.5 and an enzyme dosage ranging from 12 to 30 u g−1. Complete dephosphorylation of soya bean protein isolates was performed at 60°C, a pH value of 4.5 and an enzyme dosage of 12 u g−1. In the gastrointestinal tract of broilers the in‐vivo dephosphorylation of phytates present in feed was observed when the preparation of acid phosphatase was added to the diet.

Phytate Phosphorus Intake and Disappearance in the Gastrointestinal Tract of High Producing Dairy Cows

Thirty Holstein cows were fed diets of 50% grain and 50% corn silage (dry matter basis) through the first 18 wk of lactation. Grain mixes were supplemented with inorganic calcium sources (aragonite, calcite flour, or albacar) to provide .6 or .9% dietary calcium (dry matter basis). Phytate phosphorus intake averaged 38.3 and 42.6 g/d in digestion trials conducted during wk 4 and 10 of lactation, respectively. Even though large quantities of feed and significant amounts of grain were consumed, 98% of dietary phytate phosphorus was hydrolyzed to inorganic phosphorus. Neither calcium source nor calcium quantity affected the hydrolysis of phytate phosphorus.

EFFECTS OF FERMENTATION ON PHYTATE PHOSPHORUS AND MINERAL CONTENT IN BLACK GRAM, RICE, AND BLACK GRAM AND RICE BLENDS

ABSTRACTQuantitative changes in phosphorus compounds and mineral content of black gram, rice, and black gram and rice blends were investigated during fermentation. Black gram cotyledons and polished Texas long‐grain rice had phytate phosphorus content of about 4.80 and 0.97 mg/g, respectively, on a dry weight basis. Phytate phosphorus accounted for about 51% of total phosphorus in rice. Fermentation of rice alone for 8 hr resulted in complete hydrolysis of phytate phosphorus with simultaneous increase in the quantities of nonphytate phosphorus. At 45 hr fermentation, about 13.33% and 48.80% of phytate phosphorus was hydrolyzed in black gram and black gram and rice blends, respectively, with subsequent increases in non‐phytate phosphorus. No apparent changes were observed in the concentrations of calcium, magnesium, zinc, and iron; the inorganic sulfur content was decreased in black gram, rice, and black gram and rice blends as the fermentation progressed to 45 hr. The 20‐hr fermented black gram and rice batter was judged to produce an optimum quality of steamed product (Idli) which contained about 1.51 mg/g of phytate phosphorus. Scanning electron microscopy was employed to study the physical changes in the black gram and rice fermented batters and Idli. The Idli had a fine net work (spongy) type of texture and did not contain the starch granules compared to corresponding unsteamed samples.

The Hydrolysis of Phytate Phosphorus by Chicks and Laying Hens

The chromic oxide balance method was used to determine the amount of natural phytate phosphorus hydrolyzed by chicks and laying hens. Broiler chicks 4 and 9 weeks old and Single Comb White Leghorn hens were fed diets containing corn as the only grain source or diets in which wheat replaced one half of the corn. Feces were collected twice daily during the 7-day test period.The phytate phosphorus recovered in the feces of the 4 and 9 week old chicks and the laying hens fed the diet containing corn was 100, 98, and 92%. When wheat replaced one half of the corn the recovery was 92, 87 and 87%. The phytase activity in wheat was minimal in vivo; whereas, in vitro tests indicated enzyme activity.

Ruminant Nutrition, Phytate Phosphorus Hydrolysis and Availability to Rumen Microorganisms

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRuminant Nutrition, Phytate Phosphorus Hydrolysis and Availability to Rumen MicroorganismsArthur Raun, Edmund Cheng, and Wise BurroughsCite this: J. Agric. Food Chem. 1956, 4, 10, 869–871Publication Date (Print):October 1, 1956Publication History Published online1 May 2002Published inissue 1 October 1956https://doi.org/10.1021/jf60068a006RIGHTS & PERMISSIONSArticle Views277Altmetric-Citations42LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (266 KB) Get e-Alerts Get e-Alerts