Concentrations Of Phytase Research Articles

Response of YPM x Ross 708 male broilers to diets containing varying inclusions of phytase, calcium butyrate, and bacitracin methylene disalicylate from 1 to 42 d of age–part 1: performance, processing yields, and nutrient digestibility

This 42-d study evaluated the effects of phytase, calcium butyrate (CB), and bacitracin methylene disalicylate 50 (BMD) on broiler performance, processing yields, and nutrient digestibility. Ross YPM x 708 male broilers (2,880 total) were distributed in 72 floor pens and assigned to 1 of 9 treatments (8 replicates/treatment) on d of hatch. This experiment was a 2 × 4 + 1 factorial arrangement, including 2 phytase concentrations (500 or 1,500 FTU/kg), 4 microbiota modulating feed additive groups (MMFA; none, CB (0.5 g/kg of diet), BMD (55 mg/kg of diet), or both CB and BMD), and a negative control without feed additives. Broiler performance (d 14, 28, and 42), apparent ileal nutrient digestibility (d 28 and 42), and processing yields (d 43) were determined. Day 14 BW increased with BMD inclusion compared to CB and no MMFA in the 1,500 FTU/kg group but BW were similar between all MMFA combined with 500 FTU/kg (P ≤ 0.05). Supplementing BMD increased d 28 BW and reduced d 1 to 28 feed conversion ratio compared to CB and no MMFA (main effect, P ≤ 0.05). Day 42 BW varied depending on dietary phytase concentrations. When diets contained 500 FTU/kg, broilers fed both CB and BMD had a higher BW than broilers fed only CB. Whereas when the inclusion of phytase was increased to 1,500 FTU/kg, broilers fed diets with only BMD or both CB and BMD had higher BW than broilers fed diets with no MMFA (P ≤ 0.05). Phytase concentrations at 1,500 FTU/kg increased (P ≤ 0.05) digestibility of fat (main effect, d 42), phosphorus (d 28 and 42), and apparent ileal digestible energy (main effect, d 42) compared to 500 FTU/kg. In this study, dietary BMD improved broiler growth compared to CB and no MMFA. However, these observed differences between CB and BMD were dependent on dietary phytase concentrations.

Microalgae and phytase dietary supplementation improved growth and gut microbiota in juvenile European seabass (Dicentrarchus labrax)

Fishmeal and fish oil have been the main sources of protein and fatty acid for aquaculture fish. However, their increasing price and low sustainability have led the aquafeed industry to seek sustainable alternative feedstuffs to meet the nutritional requirements of fish and improve their health and performance. Plant proteins have been successfully used to replace fishery derivatives in aquafeeds, but the presence of anti-nutritional substances is a potential drawback of this approach. Thus, it has been reported that phytate breakdown can be caused by feed supplementation with exogenous phytase. The inclusion of microalgae has been proposed to improve gut functionality in fish fed diets with a high vegetable protein content. The aim of this study was to evaluate the effect on the growth and gut microbiota of European seabass (Dicentrarchus labrax) juveniles of a diet containing a blend of microalgae (Arthrospira platensis and Nannochloropsis gaditana) and different concentrations of phytase. An 83-day feeding trial was conducted, comprising four experimental diets with 2.5% microalgae and 500, 1,000, 2,000, or 10,000 phytase units (FTU)/kg feed and a microalgae- and phytase-free control diet. At the end of the trial, a significantly increased body weight was observed in fish fed the diet with the highest phytase concentration (10,000 FTU/kg) versus controls, although the gut bacterial composition did not differ from controls in alpha or beta diversity with either majority (Weighted UniFrac) or minority bacterial strains (Unweighted UniFrac). In comparison to the control group, the groups fed diets with 1,000 or 2,000 FTU/kg diets had a lower alpha diversity (Shannon’s diversity index), while those fed diets with 500 FTU/kg or 1,000 FTU/kg showed distinct clusters in beta diversity (involving minority ASVs). According to these findings, the diet containing the 2.5% microalgae blend with 10,000 FTU/kg may be useful to increase the aquafeed quality and sustain the growth performance of juvenile European seabass.

Phytase super-dosing modulates bone parameters and the concentration of the calcium epithelial carrier calbindin-D28k in quails (Coturnix coturnix japonica) under thermal stress

Context Thermal stress causes significant changes in the bioavailability of minerals, especially calcium, in laying birds, resulting in reduced egg production, and compromising egg quality. Therefore, it is necessary to use additives that provide better nutrient availability and minimise the negative effects caused by high temperatures. Aims This study aimed to evaluate the effects of super-dosing the diet of laying quails submitted to different temperatures with phytase on their bone parameters and on the epithelial calcium transporter calbindin-D28K positivity. Methods Seven hundred and twenty (720) Japanese quails in the production phase were distributed in a completely randomised design, in a 5 × 3 factorial design, with five supplementation levels of phytase (0, 500, 1000, 1500, and 3000 FTU/kg), and three temperatures (24°C, 30°C and 36°C), totalling 15 treatments, and six replications of eight birds each. The study began at the 8th week of age and continued for two cycles of 21 days, totalling 42 days of experiment. Bone parameters of the tibias and calbindin-D28K positivity were measured by immunohistochemistry. The data were submitted to variance, Tukey, and regression analyses. Key results At 24°C, birds had higher averages for proximal, medial, and distal diaphyses than did birds at 30°C and 36°C, and a greater breaking strength of the tibias than did those at 36°C. There was an increasing linear effect on the medial diaphysis and Seedor index in the tibias with an increasing phytase supplementation level. Calcium (Ca) in the tibias was higher in birds kept at 30°C at a supplementation level of up to 1000 FTU of phytase, than in the birds at 24°C and 36°C, equalling at 1500 FTU, and lower at 3000 FTU. There was a quadratic effect for phosphorus (P) and the Ca:P ratio in the tibias of quails submitted to increasing concentrations of phytase. Quails kept at 30°C showed greater anti-calbindin-D28K positivity in the duodenum and jejunum, when compared to animals subjected to temperatures of 24°C and 36°C. Phytase doses of 500 and 1000 FTU increased calbindin-D28K positivity in the duodenum of quails kept at 30°C. At a supplementation level of 1500 FTU, phytase provided greater eggshell thickness and greater calbindin-D28K positivity in the uterus of quails kept at 36°C. Conclusions Therefore, it is recommended to use 1500 FTU of phytase for Japanese quail exposed to high temperatures. Implications These findings suggest that dietary phytase super-dosing can help alleviate thermal stress in Japanese quail.

Standardized total tract digestibility of phosphorus in field peas fed to growing pigs is increased by microbial phytase, but particle size and origin of field peas do not affect digestibility of phosphorus

Two experiments were conducted to test the hypothesis that particle size or origin of field peas does not influence apparent total tract digestibility (ATTD) or standardized total tract digestibility (STTD) of P, but that increasing levels of phytase will increase ATTD and STTD of P in field peas when fed to growing pigs. In experiment 1, one source of field peas was obtained from the U.S., and two sources were obtained from Canada (i.e., Canada 1 and Canada 2). The U.S. field peas were ground to 265, 457, or 678 µm, whereas the Canada 1 peas were ground to 253 µm, and the Canada 2 source was ground to 411 µm. The five batches of field peas were each included in one diet and fed to 50 growing pigs (16.36 ± 1.19 kg) with 10 replicate pigs per diet. In experiment 2, six diets based on the U.S. field peas ground to 678 µm were formulated to contain 0, 250, 500, 1000, 2000, or 4000 units per kg of microbial phytase and fed to 48 pigs (15.26 ± 0.91 kg) with eight replicate pigs per diet. In both experiments, field peas were the only source of P in the diets. Pigs were housed individually in metabolism crates and feces were collected for four days. Results of experiment 1 indicated that the ATTD and STTD of P were not affected by source of peas or by particle size of the field peas and it was concluded that growing location and variety do not influence STTD of P in field peas. Results of experiment 2 indicated that the ATTD of Ca and P and the STTD of P increased (linear, P < 0.001) as phytase increased in the diets, and fecal excretion of Ca and P was reduced as the concentration of dietary phytase increased (linear, P < 0.001). It was, therefore, concluded that if microbial phytase is included in diets containing field peas, the inclusion of feed phosphate can be reduced, and manure concentration of P will also be reduced. In conclusion, the hypotheses that neither growing location nor particle size influences STTD of P were confirmed, and the hypothesis that increased concentration of dietary phytase increases STTD of P was also confirmed.

Effects of phytase inclusion in diets containing rice protein concentrate (RPC) on the nutrient digestibility, growth and chemical characteristics of rohu (Labeo rohita).

The objective of the current study was to assess the impact of dietary phytase supplementation on Labeo rohita fingerlings and to examine the effects on growth, nutrient digestibility and chemical characteristics of diets containing rice protein concentrate (RPC) as a major protein source. Six experimental diets were made, i.e., a positive control (fishmeal-based diet with no phytase), FM0; a negative control (RPC-based diet with no phytase), RPC0; and four supplemental phytase levels (250, 500, 1000, and 2000 FTU/kg). Fingerlings with an average weight of 9.42 ± 0.02 grams (mean ± SD) were randomly distributed into six experimental groups of three replicates, each containing 25 fish per tank (75 liters of water), provided with experimental diets at a rate equivalent to 5% of their body weight for 90 days, and uneaten feed was collected after 2 hours to determine feed consumption. The feces were collected before feeding to estimate digestibility. Phytase in combination with the RPC-based diet significantly (p < 0.05) enhanced phytate phosphorus in vitro hydrolysis; growth performance; nutrient (crude protein, crude fat, moisture and gross energy) and mineral (P, Ca, Mg, Na, K, Zn, Mn and Cu) digestibility; digestive enzyme (protease, lipase and amylase) activity; and mineral deposition up to 1000 FTU/kg phytase. However, the hepatosomatic and viscerosomatic indices and carcass composition were not influenced (p > 0.05) by phytase supplementation. Increasing phytase supplementation in the RPC-based diets led to a significant (p < 0.05) decrease in the serum biochemical parameters (alkaline phosphatase activity, aspartate aminotransferase, alanine aminotransferase), which resulted in improved liver health. In conclusion, phytase-supplemented RPC-based diets improved the growth, mineral/nutrient digestibility, digestive enzymes, serum biochemistry, and mineral deposition of L. rohita fingerlings up to 1000 FTU/kg. Broken line regression analysis revealed that the optimum phytase concentration in the RPC-based diet for L. rohita was 874.19 FTU/kg.

256 Anchor Talk: Accounting for effects of microbial phytase on digestibility of calcium and phosphorus

Abstract Inclusion of increasing levels of microbial phytase in diets for weanling and growing pigs results in a linear increase in the standardized total tract digestibility (STTD) of Ca and P. In many experiments, maximum effects on STTD of Ca and P were obtained with inclusion of around 1,200 phytase units (FTU) per kg of diet, although some of the newer phytases appear to release Ca and P until at least 2,000 FTU is included in the diets. In most individual feed ingredients and most practical diets, the maximum standardized total tract digestibility (STTD) of P that is obtained by using between 500 and 1,000 FTU per kg diet is around 70%, whereas the STTD of Ca for some ingredients can be over 80% if microbial phytase is used. One reason for the decreased STTD of P than of Ca in diets with maximum dosages of phytase is that dietary Ca prevents some P from being absorbed, and the STTD of P in practical diets, therefore, will never be 100% regardless of phytase inclusion. It is, however, important that the increased STTD of dietary Ca that is caused by phytase is taken into account in diet formulation because of the negative effects of Ca on STTD of P. In addition, at low dietary phytase there is release of more Ca than P, whereas at greater inclusion levels of phytase, there may be a similar release of Ca and P. Release of Ca and P by phytase is also impacted by ingredient composition in the diets because phytase does not have the same effect on all ingredients. In general, ingredients with low concentration of phytate have greater STTD of P if no phytase is used than ingredients with greater concentrations of phytate P, but the response to phytase is greater for ingredients with high concentrations of phytate. Sows also have lower digestibility of Ca and P than growing pigs and the response to phytase in diets for sows is less than in diets for growing pigs. Likewise, there is a linear reduction in phytase effects on STTD of both Ca and P as pigs get older. In contrast, in diets for newly weaned pigs there are specific advantages to using high concentrations of phytase (at least 2,000 FTU) because gastric pH is reduced in diets with phytase, which results in less diarrhea. This effect may be related to increased concentrations of plasma inositol in pigs fed diets with phytase, which may positively impact the immune status of the pigs. In conclusion, use of phytase in diets for pigs results in increased STTD of Ca and P and may have other benefits as well.

Supplemental phosphorus can be completely replaced with microbial phytase in White Leghorn layer diets

ABSTRACT 1. A study was conducted to assess the possibility of totally replacing supplemental phosphorus sources in White Leghorn (WL) layer diets (aged 28 to 45 weeks of age) with microbial phytase supplementation. One thousand commercial layers (HyLine White) of 28 weeks of age were housed in California cages fitted in open-sided poultry shed at the rate of 20 layers in each replicate. Ten replicates were randomly allotted to each treatment, and the respective diet was fed from 28 to 45 weeks of age. 2. A control diet (CD) containing the recommended levels of non-phytate phosphorus (3.6 g/kg NPP) and four other test diets (2–5) having sub-optimal levels of NPP (2.4, 2.0, 1.6 and 1.2 g/kg), but with supplemental microbial phytase (600 FTU/kg) were prepared and fed for the trial duration. 3. The layers fed with lower levels of NPP with phytase had the same laying performance as the group fed the CD. Egg production, feed efficiency, egg mass, shell defects, egg density, shell weight, shell thickness, ash content and breaking strength of the tibia and sternum were not affected by feeding the lowest concentration of NPP (1.2 g/kg) plus microbial phytase. 4. Phytase supplementation in diets with sub-optimal levels of NPP (2.4, 2 and 1.6 g/kg) significantly improved the Haugh unit score compared to those fed the CD. 5. It was concluded that supplemental phosphorus can be completely replaced with microbial phytase (600 FTU/kg) in a diet without affecting egg production, shell quality or bone mineral variables in WL layers (28 to 45 weeks).

Holo-analysis of the effects of xylo-oligosaccharides on broiler chicken performance

ABSTRACT 1. Xylo-oligosaccharides (XOS) stimulate proliferation of beneficial bacteria in the gastrointestinal tract of broiler chickens. This results in enhanced utilisation of dietary non-starch polysaccharides and increased production of valuable short-chain fatty acids. However, these positive effects do not always translate into improved bird productive performance, with inconsistent performance responses observed between bird trials. 2. A holo-analysis was conducted to determine the effects of supplementing XOS into broiler diets on bird feed intake, body weight gain, feed conversion and mortality. This was done by comparing the XOS supplemented treatment to the control treatment. A total of 53 studies which met the criteria for inclusion were used in the analysis. 3. The results showed that XOS had a notable positive impact on bird mortality; XOS reduced mortality by 0.69% for every 1% increment in the control group. XOS supplementation induced a positive effect on the feed conversion ratio (FCR). However, the efficacy of XOS at improving FCR was dependent on the efficiency of the control group (performance of the flock), and the concentration of total arabinoxylan, protein and phytase in the diet. There were insufficient data points to predict the effect of XOS on body weight and feed intake. 4. In conclusion, the holo-analysis revealed that supplementing XOS to broiler chicken diets reduces bird mortality. XOS can also improve FCR, but the scale of response is dependent on the diet composition and control flock performance. Additional studies are required to confirm the effects of XOS on body weight and feed intake.

Prediction of ileal digestible phosphorus in broiler chicken diets supplemented with exogenous phytase

The objectives were to develop equations for predicting ileal digestible phosphorus (P) based on nonphytate P, phytate P, calcium to nonphytate P ratio, and exogenous phytase concentrations in broiler diets and to evaluate the accuracy of the models. The modified Michaelis–Menten model was used to predict apparent ileal digestible (AID) or standardized ileal digestible P in broiler diets. Two different methods were used to analyze 25 published ileal digestible P data to evaluate the accuracy of the equation for predicting AID P. The first method assessed mean and linear biases. While the mean bias was significant ( P &lt; 0.05), the linear bias was not significant. The second method involved regressing the 25 AID P data against those predicted by the current model. The results showed that the intercept and slope of the regression were not statistically different from 0 and 1, respectively. This suggests that the current equation accurately represents the test data. In conclusion, the accuracy of the model depends on validation processes. Considering that the current model was developed using various phytase products, it would be preferable to use an equation that is based on a single phytase product if requisite quantity of data is available.

Effect of day-old chick weight on the response of broilers to high doses of exogenous phytase

A total of 360 Ross 708 male broiler chicks were used in an 8 treatment and 9 replicate cage study to explore the influence of day-old chick weight on the efficacy of exogenous phytase. Treatments were arranged as a 2 × 4 factorial with the factors being diet (a positive (PC) and negative control (NC) varying in nutrient density fed without or with 2 concentrations of exogenous phytase) and chick weight (light; <38.5 g or heavy; >42 g). Chicks were sourced from the same breeder flock, with light and heavy chicks being selected from the naturally occurring heterogeneity in the population. The diets were corn-soybean meal based and the PC was formulated to meet the nutrient requirements of male broiler chicks. The NC was formulated to contain 120 kcal/kg, 0.5, 0.18, and 0.18% less apparent metabolizable energy (AME), crude protein (CP), calcium (Ca), and phosphorus (P), respectively, than the PC. Amino acid (AA) density in the NC was also reduced in line with the reduction in CP and the manufacturers' recommendations for the effect of phytase on amino acid digestibility. Phytase at either 1,000 FYT/kg or 3,000 FYT/kg was added only to the NC to create a total of 4 diets. Water and mash feed were available ad libitum and were offered to 8 replicate cages, each containing 5 chicks. The experiment was conducted over a period of 3 wk and diets were offered in 2 phases (starter from d 1 to 10 and grower from d 11 to 21). Growth performance was monitored at the end of each diet phase and on d 21 ileal digesta were collected for estimation of apparent digestibility of energy (DE), nitrogen (N), Ca, P, dry matter (DM), and AA. There were no statistically significant interactions between diet and day-old chick weight for any of the measured parameters. Light chicks had significantly lower weight gain (approx. 5%) at both d 10 and d 21 compared with heavy chicks. This effect was principally associated with reduced feed intake and there was no significant effect of chick weight on feed conversion ratio (FCR). Chick weight had no effect on ileal nutrient digestibility. The reduction in nutrient density from the PC to the NC generated a significant reduction in weight gain (around 12%) and a significant increase in FCR (1.68 vs. 1.83). This effect was associated with a significant reduction in ileal DE (approximately 150 kcal/kg) and in the digestibility of several AA. Exogenous phytase significantly increased weight gain, reduced FCR and generated a significant increase in the ileal digestibility of energy, N, P, and several AA. Although chick weight and diet did not interact statistically, heavy chicks benefited more than light chicks from high doses of exogenous phytase across almost all measured end points which was confirmed by regression analysis. In conclusion, light chicks have inferior performance outcomes than heavy chicks principally because of reduced feed intake, but putatively not in digestive capacity per se. Exogenous phytase is effective in improving performance and nutrient digestibility in nutrient deficient diets. The effect of chick weight per se, and also breeder flock age, on the utility of supra-nutritional inclusion concentrations of exogenous phytase warrants further study.

Phosphorus equivalency of exogenous phytase relative to phosphorus in monosodium phosphate in broiler chickens

The objective of this study was to estimate phosphorus (P) equivalency of exogenous phytase relative to P from monosodium phosphate (MSP) in broiler chickens. To attain this objective, the impact of dietary MSP or exogenous phytase on growth performance, ileal digestibility of P, and bone characteristics in broiler chickens was assessed. Six experimental diets consisting of a P-deficient basal diet based on corn and soybean meal, basal diet plus 0.9 or 1.8 g/kg of inorganic P from MSP, and basal diet plus 500, 1,000, or 2,000 FYT/kg of exogenous phytase. Calcium to P ratio in all diets was maintained at 1.5:1. A total of 576 male broiler chickens (Cobb 500; initial BW=190 ± 17 g) on d 8 post hatching were allotted to the 6 dietary treatments in a randomized complete block design using BW as a blocking factor. Each dietary treatment contained 8 replicate cages with 12 birds per cage. On d 11 post hatching, 7 birds from each cage were euthanized by CO2 asphyxiation and dissected for the collection of ileal digesta. On d 18, ileal digesta were also collected from the remaining 5 birds in each cage. The left femur and tibia were collected from the bird with the median BW on d 11 and 18 from each cage, and analyzed for bone breaking strength and bone ash. Weight gain and gain-to-feed ratio linearly or quadratically increased (P < 0.05) in every period as the inclusion rate of MSP or phytase increased. Ileal digestibility of P linearly increased (P < 0.05) on d 11 with increasing MSP, but there was no significant effect on d 18. Increasing phytase concentration linearly increased (P < 0.05) ileal digestibility of P on d 11 and 18. Increasing dietary MSP or phytase linearly increased ileal digestible P concentration in diets (P < 0.05). Bone breaking strength and bone ash linearly or quadratically increased (P < 0.05) with increasing inclusion rate of MSP or phytase on d 11 and 18. The equivalency of 1,000 FYT/kg of exogenous phytase based on dietary ileal digestible P concentration was 1.5 and 1.2 g/kg of inorganic P in diets on d 11 and 18, respectively. The current results showed that the supplementation of MSP or exogenous phytase can increase growth performance, ileal P digestibility, bone breaking strength, and bone ash in young broiler chickens.

PSIV-13 Evaluation of Floor Space Restriction and Hyper-Dosing of Phytase on Growth Performance, Carcass Characteristics and Serum Chemistry of Late Finishing Pigs

Abstract This study was conducted to evaluate the impact of strategically applied hyper-dosing of phytase on growth performance, carcass characteristics and serum chemistry profile of late finishing pigs housed under space-restricted conditions. A total of 375 finishing pigs (94.63 ± 0.61 kg) were randomly assigned to 48 pens, with 7 to 8 pigs per pen equally balanced for gilts and barrows. Two phytase supplementation doses (control of 2,500 FTU/kg or hyper-dose of 5,000 FTU/kg) and two space allocation dimensions (adequate with 0.85 m2/pig or restricted with 0.66 m2/pig) were combined to create 4 treatments in a 2 x 2 factorial arrangement. Pigs were fed a finishing diet formulated to contain 0.68% standardized ileal digestible (SID) lysine, 0.55% Ca, and 0.24% available P and phytase was given equal matrix values for Ca, P, SID amino acids, and net energy for both supplementation levels. Analyzed dietary phytase concentrations were 2,970 and 6,560 FTU/kg for the 2,500 and 5,000 FTU/kg treatments, respectively. The 3 heaviest pigs per pen (2 barrows and 1 gilt) were marketed on d 28 and the remaining pigs were marketed on d 42. No interactions; P &amp;gt; 0.10) were observed between floor space allowance and phytase supplementation. Pig body weight was determined weekly and was reduced (P &amp;lt; 0.008) by restriction of space on week 3 (116.7 vs. 118.4 kg), and 4 (time of first marketing; 123.6 vs. 125.4 kg) and tended to be reduced (P &amp;lt; 0.08) on week 5 (125.5 vs. 127.8 kg), and 6 (second marketing; 133.0 vs. 135.3 kg). Body weight considering all pigs marketed (d 28 and d 42) was reduced (P = 0.009; 133.9 vs. 135.4) by space restriction. Space restriction reduced ADG during week 1, 3, the first marketing period, and for all pigs marketed (P &amp;lt; 0.05). Similarly, ADFI was reduced in space restricted pigs for all periods (P ≤ 0.001), but gain:feed was not impacted (P &amp;gt; 0.08). Back fat depth and loin eye area measured using ultrasound was not impacted by space restriction. Hyper-dosing with phytase did not impact (P &amp;gt; 0.06) growth performance or carcass characteristics, regardless of space allowance. Space restriction and phytase supplementation did not impact serum chemistry except for increased serum total protein and decreased urea N (P &amp;lt; 0.05) due to space restriction and decreased aspartate transaminase with hyper-dosing phytase. Results indicate that restricted floor space allowance reduced growth rate, feed intake and body weight of late finishing pigs and that hyper-dosing phytase was not an effective strategy in improving growth performance regardless of space allowance.

Impact of dietary analyzed calcium to phosphorus ratios and standardized total tract digestible phosphorus to net energy ratios on growth performance, bone, and carcass characteristics of pigs.

A total of 2,184 pigs (337 × 1,050, PIC; initially 12.4 ± 0.17 kg) were used in a 143-d study to evaluate the effects of feeding varying analyzed calcium to phosphorus ratios (Ca:P) at two standardized total tract digestible (STTD) phosphorus to net energy ratios (STTD P:NE). Pens of pigs (26 pigs per pen) were assigned to 1 of the 6 dietary treatments in a 2 × 3 factorial with main effects of STTD P:NE and Ca:P ratio. Diets consisted of two levels of STTD P:NE; High (1.80, 1.62, 1.43, 1.25, 1.10, and 0.99 g STTD P/Mcal NE from 11 to 22, 22 to 40, 40 to 58, 58 to 81, 81 to 104, and 104 to 129 kg, respectively); or Low (75% of the High levels), and three analyzed Ca:P ratios (0.90:1, 1.30:1, and 1.75:1). There were 14 pens per treatment. Diets were corn-soybean meal-based and contained a constant phytase concentration within each dietary phase with levels decreasing throughout the trial (phases 1 through 3, 500 FTU/kg, assumed release of 0.13% STTD P; phase 4, 400 FTU/kg, assumed release of 0.11% STTD P; phase 5, 290 FTU/kg, assumed release of 0.09% STTD P; and phase 6, 210 FTU/kg, assumed release of 0.07% STTD P). Overall, there was a Ca:P × STTD P:NE interaction (P < 0.05) observed for average daily gain (ADG), feed efficiency (G:F), final body weight (BW), hot carcass weight (HCW), bone mineral density, bone mineral content, and bone-breaking strength. When feeding Low STTD P:NE levels, increasing the analyzed Ca:P ratio decreased (linear, P < 0.001) ADG final BW, HCW, and tended to worsen G:F, bone mineral density, and bone mineral content (linear, P < 0.10). However, when feeding High STTD P:NE levels, increasing the analyzed Ca:P ratio significantly improved bone mineral content and bone mineral density (linear, P < 0.05), and tended to improve ADG and final BW (linear, P < 0.10) and G:F (quadratic P < 0.10). Additionally, increasing the analyzed Ca:P ratio worsened ADG, G:F, and bone mineralization with Low STTD P:NE but had marginal impacts when adequate STTD P:NE was fed.

Influence of Dietary Phytase Inclusion Rates on Yolk Inositol Concentration, Hatchability, Chick Quality, and Early Growth Performance

The aim of this study was to determine the influence of dietary phytase in breeder hens on yolk nutrients, hatchability, chick quality, and growth rate of their progeny, and their subsequent performance to 42 d post-hatch when fed diets with the same phytase concentrations. Breeder hens (n = 216) were divided into 3 groups receiving nutrient-adequate diets with reduced calcium (Ca) and phosphorus (P) (by 0.16% and 0.15%, respectively), supplemented with either 500, 1500, or 4500 FTU/kg phytase from 27 to 50 weeks of age. Eggs were collected at 38 weeks of age and incubated. On the day of hatch, the chick quality and hatchability were determined, and 18 chicks/group were euthanized for yolk sac collection and the determination of inositol and glycerol concentrations. The remaining chicks were divided into three groups, receiving different diets with reduced Ca and P (by 0.16% and 0.15%, respectively), supplemented with 0, 500, or 1500 FTU/kg phytase to 42 d post-hatch. Increasing the phytase concentration in the breeder hen diet linearly (p < 0.05) increased the number of early embryo deaths and decreased the number of late deaths and pips. The inositol concentration in the yolk sac at day of hatch increased (quadratic; p < 0.05) as the phytase dose increased in the breeder hen diet. The breeder hen diet (p < 0.05) influenced the body weight (BW), feed intake (FI), and feed conversion ratio (FCR) up to 21 days of age. The supplementation of breeder hen diets with 1500 FTU/kg phytase increased the concentration of sodium (Na), magnesium (Mg), potassium (K), manganese (Mn), and zinc (Zn) in the yolk sac. The inclusion of phytase doses up to 4500 FTU/kg appeared to influence embryo mortality, chick feed intake, and BW gain to 21 days and the FCR throughout the entire production phase.

Effects of Dietary Supplementation of arginine-silicate- Inositol and Phytase Complex on Egg Quality, Egg Shell Strength, and Blood Biochemical Characteristics of Laying Hens.

This study aimed to determine the effects of Arginine silicate inositol complex (ASI; Arg=49.47 %, silicone=8.2 %, inositol=25%) supplementation on egg quality, shell strength, and blood biochemical traits of laying hens, as well as the effects of substituting inositol with varying concentrations of phytase on the traits as mentioned above. 90 Lohmann Brown laying hens, 26 weeks old, were randomly distributed in 6 treatments with 3 replicates (cage) and 5 birds per replicate. The isocaloric and isonitrogenic diets are used according to the age period requirements of the Lohmann Brown Classic management guideline. The treatments were as follows: 1ST treatment T1: received basal diet without additives, T2 received basal diet +1000 mg/kg arginine-silicate mixture (49.5±8.2 % respectively), T3 received basal diet +1000 mg/kg arginine-silicate- inositol (ASI) mixture (49.5, 8.2 , 25 % respectively), T4 received basal diet +1000 mg/kg arginine-silicate mixture (49.5±8.2% respectively) +500 FTU/kg, T5 received basal diet +1000 mg/kg arginine-silicate mixture (49.5±8.2% respectively) +1000 FTU/kg and T6 received basal diet +1000 mg/kg arginine-silicate mixture (49.5±8.2% respectively) +1000 FTU/kg +2000 FTU/kg. Results indicate a significant increase (P<0.05) in the relative yolk weight in T4, T5, and T6 (26.93, 26.83, 26.77%) compared to T1 (25.84%) and a significant increase (P≤ 0.05) in T4, T5 compared to T3 (26.02%), while no differences observed between T2 (26.17%) compared to other experimental treatments. The relative albumin weight significantly decreased (P≤0.05) in phytase supplementation treatments T4, T5, and T6 (63.21, 63.05, 63.22%) compared to T1, T2, T3 (64.99, 64.30, 64.08%), while a significant decrease (P≤0.05) observed in T3 compared to T1. The relative shell weight significantly increased (P≤0.05) in T3, T4, T5, and T6 (9.90, 9.86, 10.12, 10.02%), respectively, compared to T1, T2 (9.17, 9.53%) with a significant increase (P≤0.05) in relative shell weight in T2 compared to T1. The eggshell thickness significantly increased (P≤0.05) in T3, T4, T5, T6 treatments (0.409, 0.408, 0.411, 0.413 mm), respectively compared to T1, T2 (0.384, 0.391 mm). A significant increased (P≤0.05) was observed in eggshell thickness in T2 compared to T1. A significant increase (P≤0.05) was observed in the egg shell breaking strength in T3 and T5 treatments (59.40, 58.83) compared to T1 and T2 (46.20, 48.23). No significant differences were observed between T4 and T6 (53.90, 53.57) compared to other experimental treatments. Non HDL, calcium, and phosphorus levels in blood serum significantly increased (P≤0.05) in T3, T4, T5, and T6 treatments compared to T1 and T2 treatments.

Effects of Supplementation of Zinc, Manganese, or Copper and Different Phytase Levels in Serum and Bone Acid and Alkaline Phosphatases of Broiler Chicks

The knowledge of biological trace minerals and phytase requirements for modern broiler genotypes is not established and the pressure to reduce their usage in animal feeding due to environmental issues is increasing. Here, the alkaline phosphatase (ALP) and tartarate-resistant acid phosphatase (TRAP) of the tibia and serum of broilers fed with diets containing various levels of phytase and reduced levels of zinc, manganese, and copper was evaluated. The experiment was performed using 1,200 male Cobb broilers raised according to standard commercial husbandry techniques. Data were analyzed as a 4×3 factorial arrangement with four concentrations of zinc (0.34, 0.49, 0.64, and 0.79 ppm), manganese (0.18, 0.43, 0.68, and 0.93 ppm), or copper (0.09, 0.12, 0.15, and 0.18 ppm) and three concentrations of phytase (0, 500, and 1,000 FTU/kg) for age periods of 1-21 and 36-42 days. While the dietary supplementation with copper did not induce a significant effect in bone tissue biochemical markers, serum TRAP activity of 42-day old broilers increased with higher copper levels. Increasing dietary zinc levels linearly increased ALP activity in tibia growth, suggesting that zinc is essential for longitudinal bone growth. Phytase significantly promoted the increase of TRAP and ALP activities, suggesting that manganese increased growth plate activity, accelerated calcification, and remodeled the newly formed tissue into trabecular bone. Although not every enzymatic activity was affected by the treatments, the phytase use, along with trace minerals, improved the animal response to the rapid growth required nowadays and provided the nutrients for adequate bone metabolism.

Ileal and total tract digestibility of energy and nutrients in pig diets supplemented with a novel consensus bacterial 6-phytase variant.

An experiment was conducted to test the hypothesis that increasing levels of a novel phytase increases the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients in diets fed to young pigs. A negative control (NC) diet based on corn, soybean meal, and canola meal that contained approximately 0.83% phytate (i.e., 0.23% phytate-bound P) was formulated to be deficient in Ca, P, and standardized ileal digestible amino acids (AA). Five additional diets were formulated by adding 250, 500, 1,000, 2,000, or 4,000 phytase units/kg of the novel phytase to the NC diets. Eighteen ileal-cannulated pigs (17.81 ± 1.71 kg) were allotted to a 6 × 3 incomplete Latin square design with six diets and three 11-day periods. There were three pigs per diet in each period; therefore, there were nine replicate pigs per diet. The initial 5 d of each period was considered an adaptation period to the diet. For each period, fecal samples were collected via anal stimulation on days 6, 7, 8, and 9, whereas ileal digesta were collected on days 10 and 11 using standard procedures. Results indicated that the AID of crude protein, indispensable AA, and dispensable AA was increased (quadratic, P < 0.05) as the concentration of microbial phytase increased in the diets. Dietary inclusion of the novel phytase at 1,000 or 2,000 FTU/kg increased the AID of total AA from 73.7% to 79.8%. Increasing levels of microbial phytase increased (quadratic, P < 0.05) the AID of dry matter and minerals (i.e., Ca, P, K, Mg, Cu) in the diets. Likewise, a linear increase (P < 0.05) in the AID of ash and Na was observed as the inclusion level of phytase increased in the diets. Increasing levels of microbial phytase increased (linear, P < 0.01) the AID of gross energy (GE) and starch in the diets. A quadratic (P < 0.05) increase in the ATTD of ash, Ca, P, K, and Cu in experimental diets was observed as the concentration of microbial phytase increased in the diets. The ATTD of Mg and GE also increased (linear; P < 0.05) as concentration of dietary phytase increased. In conclusion, the novel microbial phytase used in this experiment was effective in increasing the AID of dry matter, GE, starch, minerals, and AA, as well as the ATTD of gross energy and minerals in diets formulated to be deficient in Ca, P, and AA.

Effects of graded levels of phytase supplementation on growth performance, plasma myo-inositol, tibia mineralization and nutrient digestibility of meat ducks fed phosphorus-deficient diets

Two experiments were conducted to explore the effect of reduction in dietary non-phytate phosphorus (nPP) and supplementation of an exogenous phytase on growth performance, plasma myo-inositol, tibia mineralization and nutrient digestibility of meat ducks. Exp. 1 used 450 one-day-old male Cherry Valley ducks over a 42-d period to evaluate growth performance and plasma myo-inositol. The treatments (6 replicates with 15 ducks per pen) included a positive control diet (PC, 4.0 and 9.0 or 3.5 and 8.0 g/kg of nPP and Ca in starter (d 0–21) and grower (d 21–42) period, respectively), a negative control diet (NC, 1.7 g/kg nPP and 1.9 g/kg Ca less from the PC), and the NC diet plus phytase at 1000, 2000 or 3000 FYT/kg feed. Exp. 2 used 600, seven-day-old, male Cherry Valley ducks in a 14-d trial to evaluate growth performance, tibia mineralization and nutrient digestibility. Dietary treatments (10 replicate cages with 10 ducks per cage) included a PC diet (4.0 and 9.0 g/kg of nPP and Ca, respectively), a NC diet (1.5 and 6.5 g/kg of nPP and Ca, respectively), and the NC diet plus phytase at 500, 1000, 2000 or 3000 FYT/kg feed. In Exp. 1, ducks fed the NC diet had lower (P < 0.05) weight gain (d 0–21 and 0–42), feed intake (d 0–21, 21–42 and 0–42) and body weight at d 21 and 42 compared to those fed the PC diet. There was no effect of diet (P > 0.05) on FCR or plasma myo-inositol. Phytase supplementation linearly increased (P < 0.05) weight gain, feed intake, and body weight; all parameters were equivalent to the PC at 2000 or 3000 FYT/kg. In Exp. 2, ducks fed the NC diet had lower (P < 0.05) weight gain, feed intake, body weight, tibia ash weight and percentage, and P digestibility and higher (P < 0.05) FCR and Ca digestibility compared to those fed the PC diet. Phytase supplementation improved growth measurements (linear and quadratic, P < 0.05), tibia ash weight and percentage (linear, P < 0.05) and P digestibility (linear, P < 0.05). Growth measurements and P digestibility were comparable to the PC level with supplemented phytase ranging from 1000 to 2000 FYT/kg, however, tibia ash weight and percent were below the PC, regardless of the dose of phytase. In conclusion, feeding graded concentrations of phytase improved growth performance, tibia mineralization, and P digestibility in ducks. Phytase supplementation at 2000 FYT/kg could fully restore the gain and P digestibility of ducks fed nPP deficient diets to that of a nutrient adequate PC. However, in extremely nPP deficient diets, tibia ash weight and percentage require a higher supplementation of phytase, which was beyond 3000 FYT/kg.

PSVI-8 Effects of Phosphorus Level and Increasing Phytase Dose on Basal Endogenous Loss of Calcium and Balance of Phosphorus in Pigs Fed Diets Containing Phytate P at Commercial Levels

Abstract The objective was to test the hypothesis that dietary P concentration and level of phytase influences basal endogenous loss of Ca in pigs. Seventy barrows (body weight: 17.66 kg) were housed in metabolism crates and allotted to 7 Ca-free diets containing corn, potato protein concentrate, and full-fat rice bran (0.27% phytate P). A positive control (PC) diet contained P at the requirement for digestible P for 11 to 25 kg pigs. Negative control (NC) diets were formulated by reducing concentration of digestible P by 0.15% and adding a novel consensus bacterial 6-phytase variant at 0, 250, 500, 1,000, 2,000, or 4,000 phytase units/kg diet. Feces and urine samples were collected separately for 4 d after 5 d of adaptation. Dried and ground fecal samples were analyzed for dry matter, Ca, and P and urine was analyzed for P. Data were analyzed using a model that included diet as fixed effect. Positive control and NC were compared using a contrast statement and linear and exponential effects of dietary phytase were tested. Results indicated that apparent total tract digestibility of dry matter was not affected by dietary P or phytase (Table 1). The basal endogenous loss of Ca was not affected by dietary P, but exponentially (P = 0.030) decreased as dietary phytase increased. Phosphorus retention (g/d) was greater (P &amp;lt; 0.001) in pigs fed PC compared with NC without phytase. The standardized total tract digestibility (STTD) of P exponentially (P &amp;lt; 0.001) increased as phytase increased; however, retention of P as % of absorbed P decreased (linear, P = 0.006) as phytase increased because the extra P absorbed as a result of phytase could not be retained due to the lack of Ca. In conclusion, increasing the phytase dose decreased basal endogenous loss of Ca and increased STTD of P.

The effects of 1a(OH)D3 individually or in combination with phytase, and different levels of cholecalciferol on performance, tibia criteria, and plasma minerals of Japanese quails

The aim of studywas to compare efficacy of 1-α(OH)D3 alone or in combination with phytase and 1-α(OH)D3 in combination of phytase and different concentration of cholecalciferol on performance, tibia parameters, andplasma minerals of quails fed Ca-P deficient diet. A total of 280 mixed sex 5-d-old quails were allocated to 7 treatments with 5 replicates. The vitamin supplement which incorporated to basal diet did not contain cholecalciferol. The dietary treatments were as follows: Ca-P deficient diet (basal diet); basal diet + 500 FTU phytase/kg of diet; basal diet + phytase + 5 μg of 1-α(OH)D3 kg-1 of diet;basal diet + phytase + 5 μg of 1-α(OH)D3 and 250, 500, 750 and 1,000 IU of cholecalciferol kg-1of diet. The highest final body weight and the best feed conversion ratioobtained in the group supplemented with 1,000 IU cholecalciferol kg-1 of diet (p &lt; 0.05). Supplementation of 1-α(OH)D3 alone or in combination with phytase and phytase and different concentration of cholecalciferol could improve tibia parameters (p &lt; 0.05). In conclusion, supplementation of 1-α(OH)D3 alone to Ca-P deficient diet could maximize tibia mineralization, whereas it couldn't maximize performance, performance criteria were maximized by supplementation of 1,000 IU cholecalciferol kg-1 of diet.