Dietary Phytase Research Articles

Effects of dietary phytase supplementation on growth performance, nutrient digestibility, and blood metabolites of weaned piglets

Context Phytase plays a crucial role in the nutrition of piglets. Incorporating phytase into weaner pigs’ diet may alleviate the anti-nutritional effect by catalyzing the hydrolysis of phytic acid. As a result, bounded phosphorus and other minerals become more available for absorption, thereby enhancing nutrient utilization growth performance. Aims This study evaluated the efficacy of dietary phytase supplementation on the performance of weaned piglets. Methods Two hundred and forty cross-bred piglets (Yorkshire × Landrace × Duroc), of initial average bodyweight (BW) of 5.57 ± 1 kg at weaning, were assigned to five dietary treatments in a complete randomized block design. The study was conducted in the following three phases: Phase 1 (Days 1–7), Phase 2 (Days 8–21), and Phase 3 (Days 22–35). The treatments included basal diet containing 0.15% lower concentration of both total calcium and total phosphorus (NC), a standard basal diet (PC), NC + 500 phytase units per kilogram of feed (NC500), NC + 1000 phytase units per kilogram of feed (NC1000), and NC + 1500 phytase units per kilogram of feed (NC1500). Key results In Phase 1, the final BW was higher (P < 0.01) in PC and the phytase-supplemented diets than in the NC treatment. In Phase 2, Phase 3, and the overall days the average daily gain (ADG) and gain-to-feed ratio (G:F) were greater (P < 0.05) in the PC and the phytase-supplemented diets than in the NC treatments. The ADG and G:F were also higher (P < 0.01) in the phytase-supplemented diets than in the NC treatment. The digestibility of calcium, phosphorus, and blood myo-inositol was higher (P < 0.05) in the phytase-supplemented diets than in the NC treatment in Phase 2. In Phase 3, the level of blood myo-inositol was higher (P < 0.01) in the phytase-supplemented diets than in NC. Fecal inositol hexakisphosphate was lower (P < 0.01) in the phytase-supplemented diets than in NC in both Phases 1 and 2. Conclusion Dietary supplementation of phytase increased the digestibility of phytate by releasing phosphorus, calcium, and myo-inositol concentration, leading to improved growth performance. Implications Inclusion of phytase in pig diets can help farmers save money on feed additives such as phosphorus, improve environmental sustainability, and promote better growth performance.

Long story from past to present: calcium, phosphorus, and phytase

Abstract Calcium (Ca) and phosphorus (P), two main elements, have vital physiological and metabolic roles in animal bodies. Accurate comprehension of the interaction of these two elements and their value in various resources helps to obtain their optimal formulation in poultry diets. Hence, in previous studies, the hormonal axes controlling Ca and P homeostasis have been primarily investigated. However, to estimate Ca and P requirements in modern broiler chickens, in addition to growth performance, other parameters such as Ca and P digestibility, bone strength, and excretion into the environment should also be considered. Since a large amount of P in poultry feed ingredients is bound to phytate, phytases are added to poultry diets to release the P from phytate. However, many nutritionists need clarification on what dose of dietary phytase is required to release the maximum phytate P and how phytase activity will be optimized. Therefore, the present review study has attempted to explore the factors that affect the digestibility of different resources of Ca and P. In addition, the effect of excess dietary Ca on phytase activity and studies related to super dosing of phytase in broilers are provided. Finally, the values of phytate P in standard poultry feed ingredients and the latest update of the studies on determining Ca and P requirements are summarized.

Renal expression of Ca and P transporters: contrasting responses to dietary Ca and microbial phytase in broilers and growing pigs.

Enhanced dietary Ca intake linearly increases intestinal Ca absorption in pigs, but not in broilers, suggesting potential differences in whole body Ca homeostasis. To determine the role of kidney in Ca homeostasis in these species, we varied in growing pigs in experiment (Exp) 1, the dietary Ca content 2.0 vs. 9.6 g/kg and phytase 0 vs. 500 FTU/kg, in broilers, in Exp 2 the dietary Ca/retainable P from 1.3 to 2.8 and phytase 0 vs. 1000 FTU/kg, and in Exp 3 dietary Ca/P from 0.50 to 1.75. Increasing dietary Ca reduced renal mRNA expression of Ca-related transporters (TRPV5, TRPV6, CaBP-D28k, NCX1) and tight junctions (CLDN-12 and -16) in pigs, indicating Ca reabsorption was reduced to maintain Ca homeostasis. In broilers (Exp 2), high dietary Ca increased renal TRPV6, CaBP-D28k and CLDN-2 mRNA, indicating an increased capacity for Ca reabsorption. Moreover, the effect of dietary Ca was enhanced by inclusion of dietary phytase in pigs but reduced in broilers. Furthermore, increasing dietary Ca upregulated PiT-1 while phytase downregulated XPR1 mRNA expression in pigs; in broilers dietary Ca downregulated renal mRNA expression of NaPi-IIa, PiT-1, PiT-2 and XPR1, while phytase downregulated NaPi-IIa but upregulated PiT-2 and XPR1 mRNA expression. In Exp 3, Ca/P effect on transporter mRNA expression was largely consistent with Exp 2. In conclusion of this study, together with previously measured data about Ca and P homeostasis, in pigs the kidneys play a more regulatory role in Ca homeostasis than in broilers where the intestine is more important for regulation.

Dietary superdosing of phytase positively affects growth, mineral utilization and amino acid availability of channel catfish (Ictalurus punctatus)

The present study investigated the effects of supplementing high levels (superdosing) of dietary phytase on growth performance, mineral utilization and digestibility of amino acids in different regions of the gastrointestinal (GI) tract of fingerling channel catfish. The negative control (NC) diet was formulated with primarily soybean meal as a protein feedstuff which contributed 0.61 % total phosphorus (P) but was deficient in available P at 0.11 % of diet. Five other diets were formulated either with supplemental monocalcium phosphate at 1 % of diet in the positive control (PC), or supplemented with Quantum Blue phytase (AB Vista, Plantation, Florida) at 1000, 2000, 4000, or 8000 phytase units (FTU)/kg of diet. Groups of 20 catfish were each stocked into 24 aquaria operated as a closed, recirculating system with biological and mechanical filtration. All dietary treatments were assigned randomly to quadruplicate aquaria and initially fed at 6 % of total body weight per day. Feed quantities were adjusted weekly after weighing all fish in each aquarium as a group, and feeding levels were maintained close to apparent satiation throughout the 8-week feeding trial. Phytase supplementation significantly (P < 0.05) increased various responses of channel catfish including weight gain, feed efficiency, and protein retention compared to catfish fed the NC diet, resulting in values that were similar to catfish fed the PC diet. Moreover, catfish fed the phytase-supplemented diets had higher bone ash, calcium (Ca), magnesium (Mg), P, manganese (Mn), and zinc (Zn), as well as retention of Ca, Mg, P, iron (Fe), Mn, and Zn in whole-body tissues. Additionally, apparent availability of P from the posterior intestinal region increased with dietary phytase supplementation, with reduced excretion of nitrogen, Ca, Mg, P, copper (Cu), Mn, and Zn observed in comparison to fish fed the NC diet. Apparent digestibility coefficients for many of the indispensable and dispensable amino acids were increased by phytase supplementation, except for histidine, methionine, threonine, and taurine. This improvement in amino acid availability occurred only in the posterior region of the gastrointestinal tract. Channel catfish fed the diet containing 4000 FTU/kg diet had the highest postprandial plasma phosphorus level most of the time, except at 24 h after feeding. Based on these various responses, the optimal dietary phytase dosage was determined to average 5492 FTU/kg diet.

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.

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.

Nutritional and physiological responses to dietary phosphorus levels and phytase in pullets and laying hens

The objective of this study was to determine the effects of dietary available phosphorus (P) levels and dietary phytase added into the very low-P diet on the performance, mineral balance, odor emission, and stress responses in growing pullets and laying hens during 13 to 32 wk of age. One hundred sixty-eight pullets (Hy-Line Brown) were randomly assigned into 1 of 4 dietary treatments with 7 replicates of 6 birds each. Experimental diets were formulated to contain 3 graded P levels at 0.25, 0.35, and 0.45% during 13 to 15 wk (phase 1), 0.25, 0.35, and 0.45% during 16 to 18 wk (phase 2), and 0.20, 0.30, and 0.40% during 19 to 32 wk (phase 3). In addition, dietary phytase (500 FTU/kg matrix values) was added into the very low-P diets (0.20% during 13-15 wk, 0.25% during 16-18 wk, and 0.20% during 19-32 wk) to meet the nutritional adequacy with standard P diets. In all phases, decreasing dietary P levels did not affect (P > 0.05) growth, laying performance, and egg qualities. Decreasing dietary P levels linearly increased the relative duodenal and oviduct weights (P < 0.05), and quadratically increased the relative ovary weight in pullets (P = 0.016). Dietary phytase lowered (P = 0.021) the relative duodenal weight compared with the very low-P diet. Tibia breaking strength and tibia Mg contents in pullets were linearly lowered (P < 0.05) as dietary P levels decreased. Dietary phytase tended to increase (P = 0.091) tibia breaking strength and significantly increased (P = 0.025) tibia Mg content compared with the very low-P diet. Dietary P levels and dietary phytase affected (P < 0.05) ileal crypt depth and ileal villus height: crypt depth ratio in pullets. Decreasing dietary P levels linearly decreased (P < 0.01) crude fat digestibility and P excretion in both pullets and laying hens. Dietary phytase reversed (P < 0.05) the very low-P diet-mediated decrease of crude fat digestibility in pullets and laying hens. Dietary P levels and dietary phytase affected (P < 0.05) odor emission including ammonia in pullets and total volatile fatty acids in laying hens. Finally, lowering dietary P levels increased (P < 0.01) yolk corticosterone concentrations and the increased corticosterone concentration by the very low-P diet was reversed by dietary phytase. Collectively, our study shows that decreasing dietary P levels induced nutritional and physiological responses in pullets and laying hens and these P-mediated negative effects were mitigated by dietary phytase.

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.

248 Effects of feeding finishing pig diets differing in Ca:P ratio, added phytase and 25(OH)D3 on growth performance, serum 25(OH)D3, carcass characteristics, and bone characteristics

Abstract A total of 2,160 pigs [337 × 1050, PIC; initial body weight (BW) = 33.2 ± 1.4 kg] were used in a 114-d trial to determine the effects of feeding diets differing in Ca:P ratio and added phytase or phytase and 25(OH)D3 (Hy-D, DM Nutritional Products, Parsippany, NJ) on growth performance, carcass characteristics, serum 25(OH)D3, and bone characteristics. Pigs were housed in mixed sex pens with 27 pigs per pen and 20 pens per treatment. The four treatments were assigned to pens in a randomized complete block design and consisted of 1) a high phosphorus (HP) diet with standardized total tract digestibility (STTD) P at 115% of NRC (2012) requirement estimate without added phytase and formulated to a 1.25:1 Ca to P ratio; 2) low phosphorus (LP) diet with STTD P at 80% of NRC requirement without added phytase and formulated to a 1.25:1 Ca to P ratio; 3) HP with phytase (HP+phytase) diet with STTD P at 115% of NRC requirement using 0.125% STTD P release from 600 FYT/kg HiPhorius and 1.1:1 Ca to P ratio; and 4) Diet 3 except 25(OH)D3 replaced most of the vitamin D3 in the diet (HP+25(OH)D3). Diets were fed in 4 phases from 32 to 50, 50 to 75, 75 to 100, and 100 to 133 kg. For overall growth performance, source of vitamin D had no impact on performance. Pigs fed HP diets had improved (P &amp;lt; 0.05) average daily gain (ADG), average daily feed intake (ADFI) and gain to feed ratio (G:F) compared with those fed LP diets, and increased ADFI compared with those fed the HP+phytase diets (Table 1). For 25(OH)D3 measured on d 50, pigs fed the HP diets had increased (P &amp;lt; 0.05) serum 25(OH)D3 compared with pigs fed the LP diets and pigs fed the HP+25(OH)D3 diets had increased (P &amp;lt; 0.05) serum 25(OH)D3 compared with pigs fed the HP+phytase diets. Pigs fed the HP diets had greater (P &amp;lt; 0.05) HCW and percentage lean than those fed LP diets. For bone analysis, pigs fed HP diets had greater (P &amp;lt; 0.05) bone ash (g) and breaking strength than pigs fed LP or HP+phytase and 1.1:1 Ca to P ratio. In conclusion, compared with pigs fed LP diets, HP-fed pigs had improved performance and HCW. Dietary 25(OH)D3 replacing D3 did not impact performance but increased circulating 25(OH)D3.

43 Evaluating the effects of HiPhorius phytase added in diets at or below the P requirement on nursery pig growth performance and bone mineralization

Abstract A total of 297 pigs (DNA 241 × 600; initial body weight = 8.64 ± 0.181 kg) were used in a 21-d trial to evaluate the effects of HiPhorius phytase (dm-firmenich, Parsippany, NJ) on pig growth performance and bone mineralization. All pigs were fed P depletion diets (0.09% aP) for a 3-d period before the start of the study (d 14 after weaning). Pens of pigs were then assigned to 1 of 5 treatments in a randomized complete block design with 5 pigs per pen and 12 replications per treatment. The first three diets were formulated to contain 0.09% aP; without added phytase (control), or control with 600 or 1,000 FYT/kg of added phytase (considering a release of 0.15 or 0.18% aP, respectively). The remaining two diets were formulated to contain 0.27% aP, one without added phytase and the other with 1,000 FYT/kg. One pig per pen was euthanized on d 21 and the right fibula, 10th rib, and metacarpal were collected to determine bone density, bone ash, and bone Ca and P. From d 0 to 21, increasing phytase in diets containing 0.09% aP increased (linear, P ≤ 0.002) average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F) and increased percentage bone ash in metacarpals and 10th ribs (linear, P &amp;lt; 0.001; quadratic, P = 0.004, respectively), and increased grams of Ca and P in all three bones (linear, P ≤ 0.027; Table). Adding 1,000 FYT/kg in diets with 0.27% aP did not impact growth performance, but increased percentage bone ash (P ≤ 0.038) in all bones and grams of Ca and P in fibulas and 10th ribs (P ≤ 0.023) compared with pigs fed 0.27% aP without added phytase. Increasing aP from 0.09% to 0.27% in diets without added phytase increased (P &amp;lt; 0.001) ADG, ADFI, and G:F and increased bone density (P ≤ 0.002) in fibulas and metacarpals, percentage bone ash in all bones (P ≤ 0.074), and increased (P &amp;lt; 0.05) grams of Ca and P in fibulas and 10th ribs. Increasing aP from 0.09 to 0.27% aP in diets with 1,000 FYT added phytase increased bone density (P ≤ 0.008) in fibulas and metacarpals, percentage bone ash in all bones (P ≤ 0.002), and grams of Ca and P in fibulas and 10th ribs (P &amp;lt; 0.05). For growth performance (average of ADG and G:F), aP release was calculated to be 0.170% for 600 FYT/kg and 0.206% for 1,000 FYT/kg. For the average of all 3 bone measurements (average of 3 bones for bone density and percentage bone ash), aP release was calculated to be 0.120% and 0.125% for 600 and 1,000 FYT/kg, respectively.

Can the use of phytase in feed improve the performance and health of broiler chickens?

This study aimed to evaluate the effect of phytase supplementation on feeds with reduced nutritional calcium and phosphorus on broiler chickens from 1 to 49 days of age. Chickens fed five experimental diets distributed in a completely randomized design, with eleven replicates of 20 chickens each, were used for evaluating performance, bone quality, and serum mineral levels. The diets consisted of one positive control (PC); one negative control (NC), with reduced levels of available phosphorus and calcium; and four diets consisting of NC feed supplemented with phytase at levels 0, 500, 1000, or 1500 U/kg. Supplementation with 1000 FU/kg of phytase in diets based on corn, and soybean meal is ideal for obtaining excellent performance and bird welfare results reducing nutrient excretion and improving digestion and absorption of nutrients by the animal.

Effects of dietary phytase with or without multi-carbohydrase supplementation on growth performance, nutrient digestibility, and bone traits in nursery pigs

The aim was to determine the effects of supplementing increasing doses of phytase alone or in combination with a multi-carbohydrase blend to a phosphorus (P)-deficient diet for nursery pigs on growth performance, nutrient digestibility, and metacarpal bone characteristics. A total of 192 weaned pigs (7.7 ± 0.05 kg) were allotted to one of eight dietary treatments each with eight replicates in a randomized complete block design based on initial body weight. Fecal samples (days 18, 19, and 20) and metacarpal bones (day 21) were collected to determine apparent total tract digestibility (ATTD) of energy and nutrients and bone mineralization, respectively. During week 3 and overall period, increasing doses of phytase quadratically increased ( P &lt; 0.05) average daily gain. The ATTD of ash and P quadratically increased ( P &lt; 0.05) when doses of phytase increased. Phytase had quadratic ( P &lt; 0.05) effects by increasing fat-free dry weight, ash content, and P in metacarpal bone. In conclusion, increasing levels of phytase quadratically improved growth performance in week 2, nutrient digestibility, and bone traits of pigs fed a P-deficient diet. In general, however, there was no effect of multi-carbohydrase supplementation on growth performance and metacarpal characteristics in nursery pigs.

Effect of Phytases in Pig Diets on Production Performance: Meta-analysis

Feeding is one of the most critical items in pig production. Phosphorus, protein, and energy sources represent the most expensive ingredients in the feed. Phytases are enzymes used for many years to take advantage of plant phosphorus and reduce costs. Despite many studies with various methodologies and results, they have not been thoroughly systematized. Therefore, this research aims to evaluate the effect of the inclusion of phytases on performance in pigs. Effect size, heterogeneity, meta-regressions, and publication bias were determined. Phytase-supplemented pigs gained 25.17 g (p &lt; 0.05) more daily weight than controls. Piglets can gain up to 39.89 g (p &lt; 0.05). The pigs ingested a greater amount of feed, 23.44 and 28.61 g (p &lt; 0.05), per day than the control in the general analysis and piglets, respectively. Crude protein, metabolizable energy, total calcium and phosphorus, duration, and level of phytases in the diet affected performance (p &lt; 0.05). No publication bias was found. Including phytases favors weight gain and feed intake in general pigs and piglets but not in growing-finishing pigs. The effect of other nutrients and the duration and level (dose) of phytases must be considered at the time of formulation.

Effect of dietary phytase and protease supplementation on the growth performance and apparent nutrient digestibility in juvenile Pacific white shrimp (Litopenaeus vannamei) fed fish meal–free and phosphorus limiting diets

Effect of dietary phytase and protease supplementation on the growth performance and apparent nutrient digestibility in juvenile Pacific white shrimp (Litopenaeus vannamei) fed fish meal–free and phosphorus limiting diets

Research Note: Evaluation of phytic acid disappearance, ileal P digestibility, and total tract P retention in canola meal supplemented with increasing levels of exogenous phytase using conventional and cecectomized precision-fed roosters and growing chicks

Apparent ileal digestibility (AID) of P, apparent total tract retention (ATTR) of P, and phytic acid disappearance in canola meal were evaluated in the presence of increasing levels of exogenous phytase. In Experiment 1, a precision-fed rooster assay was used to determine phytic acid (myo-inositol 1,2,3,4,5,6-hexakis; InsP6) and inositol phosphate (InsP6-3; InsP-P) disappearance in conventional and cecectomized Leghorn roosters. Roosters were crop intubated with 25 g of canola meal mixed with 0, 500, 1,000, or 2,000 FTU/kg of exogenous phytase. In Experiment 2, InsP6 and InsP-P disappearance and AID and ATTR of P were determined using ad libitum-fed broiler chickens. Treatments consisted of semi-purified diets containing 45% canola meal as the sole source of P. Phytase was added to increase phytase activity by 0, 500, 1,000, or 2,000 FTU/kg. Experiments contained 6 replicates per treatment. Canola meal contained a high phytase activity (1,630 FTU/kg as-fed) due to contamination with a commercially available phytase at the feed mill from which the canola meal was sourced. In Experiment 1 with precision-fed roosters, there was no effect (P > 0.05) of phytase or bird type on InsP6 and InsP-P disappearance; however, phytase linearly reduced (P < 0.05) InsP3 concentrations in excreta. In Experiment 2 with ad libitum-fed chickens, phytase linearly increased (P < 0.05) ileal InsP6 and InsP-P disappearance, and phytase had a quadratic effect (P < 0.05) on excreta InsP6 and InsP-P disappearance. Increasing dietary phytase activity resulted in a linear increase (P < 0.05) in AID of P and phytase had a quadratic effect (P < 0.05) on ATTR of P. In conclusion, titration of high levels of phytase (1,600 to 3,600 FTU/kg as-fed) reduced InsP3 concentrations in precision-fed roosters but did not affect overall phytic acid hydrolysis, which was 78% or greater for all treatments; however, increasing the total phytase activity from 700 to 2,700 FTU in ad libitum-fed broiler chickens increased phytic acid disappearance and P digestibility.

Effect of dietary calcium source, exogenous phytase, and formic acid on inositol phosphate degradation, mineral and amino acid digestibility, and microbiota in growing pigs.

The choice of the calcium (Ca) source in pig diets and the addition of formic acid may affect the gastrointestinal inositol phosphate (InsP) degradation and thereby, phosphorus (P) digestibility in pigs. This study assessed the effects of different Ca sources (Ca carbonate, Ca formate), exogenous phytase, and chemical acidification on InsP degradation, nutrient digestion and retention, blood metabolites, and microbiota composition in growing pigs. In a randomized design, 8 ileal-cannulated barrows (24kg initial BW) were fed 5 diets containing Ca formate or Ca carbonate as the only mineral Ca addition, with or without 1,500 FTU/kg of an exogenous hybrid 6-phytase. A fifth diet was composed of Ca carbonate with phytase but with 8g formic acid/kg diet. No mineral P was added to the diets. Prececal InsP6 disappearance and P digestibility were lower (P ≤ 0.032) in pigs fed diets containing Ca formate. In the presence of exogenous phytase, InsP5 and InsP4 concentrations in the ileal digesta were lower (P ≤ 0.019) with Ca carbonate than Ca formate. The addition of formic acid to Ca carbonate with phytase diet resulted in greater (P = 0.027) prececal InsP6 disappearance (87% vs. 80%), lower (P = 0.001) InsP5 concentration, and greater (P ≤ 0.031) InsP2 and myo-inositol concentrations in the ileal digesta. Prececal P digestibility was greater (P = 0.004) with the addition of formic acid compared to Ca carbonate with phytase alone. Prececal amino acid (AA) digestibility of some AA was greater with Ca formate compared to Ca carbonate but only in diets with phytase (P ≤ 0.048). The addition of formic acid to the diet with Ca carbonate and phytase increased (P ≤ 0.006) the prececal AA digestibility of most indispensable AA. Exogenous phytase affected more microbial genera in the feces when Ca formate was used compared to Ca carbonate. In the ileal digesta, the Ca carbonate diet supplemented with formic acid and phytase led to a similar microbial community as the Ca formate diets. In conclusion, Ca formate reduced prececal InsP6 degradation and P digestibility, but might be of advantage in regard to prececal AA digestibility in pigs compared to Ca carbonate when exogenous phytase is added. The addition of formic acid to Ca carbonate with phytase, however, resulted in greater InsP6 disappearance, P and AA digestibility values, and changed ileal microbiota composition compared to Ca carbonate with phytase alone.

Amino acid and mineral digestibility, bone ash, and plasma inositol is increased by including microbial phytase in diets for growing pigs

BackgroundThe effect of microbial phytase on amino acid and energy digestibility is not consistent in pigs, which may be related to the phytase dosage or the adaptation length to the diet. Therefore, an experiment was conducted to test the hypotheses that increasing dietary phytase after an 18-day adaptation period: 1) increases nutrient and energy digestibility; 2) increases plasma P, plasma inositol, and bone ash of young pigs; and 3) demonstrates that maximum phytate degradation requires more phytase than maximum P digestibility.ResultsData indicated that increasing inclusion of phytase [0, 250, 500, 1,000, 2,000, and 4,000 phytase units (FTU)/kg feed] in corn-soybean meal-based diets increased apparent ileal digestibility (AID) of Trp (quadratic; P < 0.05), and of Lys and Thr (linear; P < 0.05), and tended to increase AID of Met (linear; P < 0.10). Increasing dietary phytase also increased AID and apparent total tract digestibility (ATTD) of Ca and P (quadratic; P < 0.05) and increased ATTD of K and Na (linear; P < 0.05), but phytase did not influence the ATTD of Mg or gross energy. Concentrations of plasma P and bone ash increased (quadratic; P < 0.05), and plasma inositol also increased (linear; P < 0.05) with increasing inclusion of phytase. Reduced concentrations of inositol phosphate (IP)6 and IP5 (quadratic; P < 0.05), reduced IP4 and IP3 (linear; P < 0.05), but increased inositol concentrations (linear; P < 0.05) were observed in ileal digesta as dietary phytase increased. The ATTD of P was maximized if at least 1,200 FTU/kg were used, whereas more than 4,000 FTU/kg were needed to maximize inositol release.ConclusionsIncreasing dietary levels of phytase after an 18-day adaptation period increased phytate and IP ester degradation and inositol release in the small intestine. Consequently, increasing dietary phytase resulted in improved digestibility of Ca, P, K, Na, and the first 4 limiting amino acids, and in increased concentrations of bone ash and plasma P and inositol. In a corn-soybean meal diet, maximum inositol release requires approximately 3,200 FTU/kg more phytase than that required for maximum P digestibility.

Digestible calcium equivalency of phytase and nutrient utilization of broiler chickens fed graded levels of limestone or phytase during the starter phase

The current study aimed to quantify the digestible Calcium (Ca) equivalency of a new phytase (HiPhoriusTM) in broiler chickens. A total of 1,152 male Cobb 500 broiler chickens were used in an experiment in which 8 diets consisting of graded levels of Ca supplied with limestone or graded levels of the phytase were fed. The 8 dietary treatments were based on a corn-soybean meal diet containing 5.1 g/kg of Ca and 5.1 g/kg of phosphorus (P) as negative control (NC); the NC + 1.3, 2.6, or 3.9 g/kg of Ca from limestone; and the NC + 500, 1000, 2000, or 4000 FYT/kg of phytase. Birds were fed the experimental diets for 3 d (from d 7 to 10) or 14 d (from d 7 to 21) to determine apparent ileal digestibility (AID) and apparent total tract retention (ATTR) of dry matter (DM), CP, Ca, and P. In the 10-d-old birds, increasing the levels of Ca decreased the AID of P and Ca (linear, P < 0.05). Increasing the levels of phytase quadratically improved (P < 0.05) the AID of Ca and P. The AID of DM and CP in the younger birds quadratically increased (P < 0.05) as the levels of Ca increased. There were linear and quadratic effects (P < 0.05) of increasing phytase level for the AID of DM and a linear effect (P < 0.05) for the AID of CP. In the 21-d-old birds, increasing Ca levels resulted in a linear decrease (P < 0.05) in the AID of CP and P, and a quadratic decrease (P < 0.05) in the ATTR of CP. Increasing phytase levels linearly and quadratically (P < 0.05) improved the AID and ATTR of CP, P, and the ATTR of Ca. The analyzed phytase activity in the diets supplemented with phytase ranged from 1,520 to 7,661 FYT/kg. The digestible Ca equivalence for dietary phytase at 1,520 to 7,661 FYT/kg ranged from 1.55 to 2.02 g/kg in the 10-d-old birds fed for 3 d and from 0.52 to 0.64 g/kg in 21-d-old birds fed for 14 d. The results showed the reduction in Ca level that could be accommodated by phytase supplementation, which is markedly different between the younger and older birds. Feeding duration influenced the impact of phytase supplementation on Ca and P digestibility, with better efficacy of phytase observed in the 10-d-old birds fed for 3 d. Also, the results showed the extra-phosphoric effects of phytase on the utilization of other essential nutrients such as protein and Ca.