Dietary Microbial Phytase Supplementation Research Articles

The impact of dietary calcium content on phosphorus absorption and retention in growing pigs is enhanced by dietary microbial phytase supplementation.

Sixty growing male pigs were used to test the hypothesis that high dietary Ca content reduces P absorption to a greater extent in microbial phytase-supplemented diets via reducing inositol phosphate (IP) degradation and enhancing P precipitation. Pigs were equally allotted over diets with three Ca contents 2·0, 5·8 and 9·6 g/kg with or without microbial phytase (0 v. 500 FTU/kg) in a 2 × 3 factorial arrangement. Faeces and urine were collected at the end of the 21-d experimental period. Subsequently, pigs were euthanised and digesta quantitatively collected from different gastrointestinal tract (GIT) segments. Increasing dietary Ca content reduced apparent P digestibility in all GIT segments posterior to the stomach (P < 0·001), with greater effect in phytase-supplemented diets in the distal small intestine (Pinteraction = 0·007) and total tract (Pinteraction = 0·023). Nonetheless, increasing dietary Ca to 5·8 g/kg enhanced P retention, but only in phytase-supplemented diets. Ileal IP6 degradation increased with phytase (P < 0·001) but decreased with increasing dietary Ca content (P = 0·014). Proportion of IP esters in total IP (∑IP) indicated that IP6/∑IP was increased while IP4/∑IP and IP3/∑IP were reduced with increasing dietary Ca content and also with a greater impact in phytase-supplemented diets (Pinteraction = 0·025, 0·018 and 0·009, respectively). In all GIT segments, P solubility was increased with phytase (P < 0·001) and tended to be reduced with dietary Ca content (P < 0·096). Measurements in GIT segments showed that increasing dietary Ca content reduced apparent P digestibility via reducing IP degradation and enhancing P precipitation, with a greater impact in phytase-supplemented diets due to reduced IP degradation.

Dietary supplementation of microbial phytase improves growth and protein efficiency ratio of freshwater prawn (Macrobrachium rosenbergii)

Phytase is a phosphatase enzyme involved in catalyzing the hydrolysis of phytic acid, which is abundant in plant-derived ingredients that are known to be best alternatives for expensive and scarce fish meal in aquafeeds. In this study, the effect of dietary supplementation of microbial phytase at 250, 500, and 750 FTU/Kg on growth, survival and body composition of freshwater prawn (Macrobrachium rosenbergii) was investigated. The growth and protein efficiency ratio in phytase-incorporated diet-fed prawns were significantly increased when compared to the phytase-free diet-fed prawns. The diet supplemented with 250 FTU microbial phytase-fed prawns showed best growth of 50.84 g in terms of mean weight, compared with the phytase-free diet-fed prawns showing 27.88 g in 90 days trial. In addition, a highest protein efficiency ratio of 2.12 was found in 250 FTU phytase-incorporated-diet-fed prawns, compared with 1.53 in phytase-free diet-fed prawns. Furthermore, there was no significant difference in the survival of prawns fed with phytase-supplemented and phytase-free diets. These results indicate that the dietary supplementation of microbial phytase in prawn diet would be beneficial in better utilization of plant-derived feed ingredients, which are of most promising alternatives to expensive and scarce fish meal in aqua feed formulation.

Dietary microbial phytase exerts mixed effects on the gut health of tilapia: a possible reason for the null effect on growth promotion.

The present study evaluated the effects of dietary microbial phytase on the growth and gut health of hybrid tilapia (Oreochromis niloticus ♀×Oreochromis aureus ♂), focusing on the effect on intestinal histology, adhesive microbiota and expression of immune-related cytokine genes. Tilapia were fed either control diet or diet supplemented with microbial phytase (1000 U/kg). Each diet was randomly assigned to four groups of fish reared in cages (3×3×2 m). After 12 weeks of feeding, weight gain and feed conversion ratio of tilapia were not significantly improved by dietary microbial phytase supplementation. However, significantly higher level of P content in the scales, tighter and more regular intestinal mucosa folds were observed in the microbial phytase group and the microvilli density was significantly increased. The adhesive gut bacterial communities were strikingly altered by microbial phytase supplementation (0·41<similarity coefficient<0·54). Stimulated intestinal inflammation and stress status were observed in the fish fed diet supplemented with microbial phytase, as indicated by the up-regulated intestinal expressions of the cytokine genes (tnf-α and tgf-β) and hsp70. In addition, the gut microvilli height was significantly decreased in the phytase group. These results indicate that dietary microbial phytase may exert mixed effects on hybrid tilapia, and can guide our future selection of phytases as aquafeed additives - that is, eliminating those that can stimulate intestinal inflammation.

Effects of the Dietary Microbial Phytase Supplementation on Bioavailability of Phosphorus in Juvenile Olive Flounder Paralichthys olivaceus Fed Soybean Meal based Diets

An 8 weeks feeding trial was carried out to evaluate the effects of dietary microbial phytase (P) supplementation on nutrient digestibility, and body composition in juvenile olive flounder Paralichthys olivaceus fed soybean meal-based diets. Seven experimental diets were formulated to be isonitrogenous and isocaloric to contain 50.0% crude protein (CP) and 16.7 kJ of available energy/g with or without dietary phytase supplementation. White fish meal (FM) provided 92.4% of the total protein in the basal diet (S0), in the other 6 diets, 30% or 40% FM protein was replaced by soybean meal: 70% FM + 30% soybean meal (S30); 70% FM + 30% SM + 1000 U phytase/kg diet (S30P1000); 70% FM + 30% SM + 2000 U phytase/kg diet (S30P2000); 60% FM + 40% SM (S40); 60% FM + 40% SM + 1000 U phytase/kg diet (S40P1000); and 60% FM + 40% SM + 2000 U phytase/kg diet (S40P2000). After two weeks of the conditioning period, triplicate groups of 25 fish initially averaging 6.15 ± 0.04 g (mean ± S.D.) were randomly distributed into the aquarium and were fed one of the experimental diets for 8 weeks. After feeding trial, supplementation of phytase significantly improved the apparent digestibility coefficients of phosphorus in flounder diets ( P<0.05) containing 30% and 40% soybean meal regardless the levels. However, phytase had no significant influence on growth performance and whole body composition of fish. Based on the experimental results, we conclude that dietary supplementation of phytase could improve the apparent digestibility coefficient of phosphorus in olive flounder.

The effect of dietary microbial phytase on mineral digestibility determined throughout the gastrointestinal tract of the growing pig fed a low-P, low-Ca corn-soybean meal diet

The study aimed to determine the impact of dietary microbial phytase supplementation on the apparent digestibility of minerals, other than P and Ca, throughout the gastrointestinal tract of the growing pig. Thirty-two entire male pigs (approximately 22kg bodyweight) were allocated equally to three dietary treatments. All diets were corn-soybean meal diets deficient in P and Ca and were either not supplemented with microbial phytase or supplemented with microbial phytase at 1107 and 2215U/kg respectively. Titanium dioxide was included in the diets as an indigestible marker. The pigs received their respective diets for 42 days and faecal samples were collected over days 40–42. On day 43, stomach chyme, terminal jejunal and terminal ileal digesta were collected post-euthanasia. Na, K, Mg, Fe, S, Cu, Mn and Zn were determined in the diets, chyme, digesta and faecal samples and apparent mineral digestibility was determined at the gastric, jejunal, ileal and total tract levels. Apparent mineral digestibility was different (P<0.01) across gastrointestinal tract locations. However, dietary microbial phytase supplementation had no effect (P>0.05) on the apparent digestibility of any of the minerals examined at any of the gastrointestinal tract locations.

Effect of microbial phytase on phytate P degradation and apparent digestibility of total P and Ca throughout the gastrointestinal tract of the growing pig1

The effect of a dietary microbial phytase on mineral digestibility throughout the gastrointestinal tract (GIT) of the growing pig was studied. Thirty-two entire male pigs (~22 kg BW) were allocated equally to 4 corn-soybean meal diets. One diet was adequate in total P and Ca, the second diet was deficient in total P and Ca (low-P diet), and the third and fourth diets were the low-P diet with microbial phytase added at 1,107 U/kg or 2,215 U/kg, respectively. Titanium dioxide (3 g/kg) was included in the diets as an indigestible marker. The pigs were fed their respective diets for 42 d. Fecal samples were collected from d 38 to 41 and stomach chyme, terminal jejunal, and terminal ileal digesta samples were collected after euthanasia on d 42. Phytate P degradability and apparent total P and Ca digestibility were determined at the gastric, jejunal, ileal, and total tract levels. Phytate P degradation and apparent total P and Ca digestibility were not significantly different between the 2 microbial phytase inclusion levels. Across both microbial phytase-low-P diets, phytase supplementation increased (P < 0.05) phytate P degradability at the jejunal, ileal, and total tract levels by 101%, 77%, and 10%, respectively, but not at the gastric level. Total tract phytate P degradation was greater (P < 0.05) than ileal phytate P degradation for both the unsupplemented (52% units greater) and phytase-supplemented, low-P (26% units greater) diets. The latter result was not reflected by the apparent total P digestibility estimate, which was not significantly different between the ileal and total tract levels for both the unsupplemented and phytase-supplemented, low-P diets. Consequently, there appeared to be considerable phytate degradation in the hindgut, presumably due to the action of hindgut microbes, but the phytate P released in the hindgut did not appear to be absorbed. Apparent Ca digestibility was not significantly different among jejunal, ileal, and total tract levels for any of the dietary treatments, but apparent Ca digestibility was greater (P < 0.05) for the phytase-supplemented diets compared with the unsupplemented diets. Overall, dietary microbial phytase supplementation led to greater phytate degradation to the end of the jejunum. Because the phytate P released in the hindgut was not absorbed, ileal estimates, rather than total tract estimates, of phytate degradation appear to more accurately reflect P availability.

Influence of a microbial phytase on the performance and the utilisation of energy, crude protein and fatty acids of young broilers fed on phosphorus-adequate maize- and wheat-based diets

1. The effects of microbial phytase on the performance and nutrient utilisation in broilers fed on phosphorus-adequate starter diets were examined in this study. The effect of phytase on the apparent ileal digestibility of fatty acids was of particular interest. Two grain types (maize and wheat) and two inclusion concentrations of a phytase enzyme from Escherichia coli expressed in Schizosaccaromyces pombe (0 or 500 phytase units (FTU)/kg of feed) were evaluated in a 2 × 2 factorial arrangement of treatments.2. Supplemental phytase improved the weight gain and feed per gain, but had no effect on the feed intake of young broilers receiving phosphorus-adequate diets.3. Phytase supplementation improved the apparent ileal digestibility of nitrogen and phosphorus in both diet types. Phytase supplementation tended to improve the apparent ileal digestible energy in wheat-based diets, but had no effect on the apparent metabolisable energy in both diet types.4. Supplementation of phytase increased the apparent ileal digestibility of fat, with similar effects for the different fatty acids measured. Increments on ileal fat digestibility due to phytase were not dependent on the type of diet.5. Dietary supplementation of microbial phytase enhanced not only the digestibility of phosphorus, but also that of nitrogen and fat, exhibiting increased ileal digestibility for all fatty acids in P-adequate maize- and wheat-based diets.

Effect of dietary microbial phytase supplementation on growth performance, nutrient utilization, body compositions and haemato-biochemical profiles of Cyprinus carpio (L.) fingerlings fed soyprotein-based diet

An 8-week feeding trial was conducted in flow through system to examine the effects of dietary supplementation of microbial phytase on growth, nutrient utilization, haemato-biochemical status and body compositions in common carp, Cyprinus carpio (L.) fingerlings (average weight 6.66 ± 0.08 g). The aim of experiment was also to determine whether dicalcium phosphates (DCP), tracemineral premix and lysine and methionine supplemental levels in carp diet could be reduced if microbial phytase was supplemented. Control diet (diet 1) supplemented with DCP, tracemineral premix and lysine and methionine without microbial phytase supplementation. Four experimental diets were formulated with reduction of either dietary DCP or trace minerals or lysine and methionine or all four supplementation levels by 100% of control diet without microbial phytase supplementation (diet 2, 3, 4 and 5 respectively). Another two experimental diets were formulated with reduction of all dietary DCP, trace minerals, lysine and methionine supplementation levels by 0 and 100% of control diet with dietary microbial phytase supplementation at 500 FTU kg⁻¹ diet (diet 6 and 7 respectively). After acclimation of fish for 2 weeks, 20 fish were randomly stocked into triplicate tanks for each of seven treatments (T₀, T₁, T₂, T₃, T₄, T₅ and T₆ for diet 1, 2, 3, 4, 5, 6 and 7 respectively) and fed with respective diet to apparent satiation. Results indicated that phytase was effective in releasing most of the phytate bound proteins, amino acids and minerals for optimum utilization and performance. Results also suggested that DCP, trace minerals and lysine and methionine supplementation level could be replaced by microbial phytase supplementation at 500 FTU kg⁻¹ in soybean-based common carp diets without altering the optimum performance of fish. Optimum replacement level of dietary DCP, trace minerals and lysine and methionine with phytase supplementation at 500 FTU kg⁻¹ soybean-based carp diet needs to be standardized in further investigations.

Dietary protein level, microbial phytase, citric acid and their interactions on bone mineralization of Labeo rohita (Hamilton) juveniles

A feeding trial was conducted for 60 days to study the eiect of dietary protein, microbial phytase and citric acid on intestinal digesta pH, bone ash and bone mineral contents in Labeo rohita juveniles. Eight experimental diets were prepared in 2 � 2 � 2 factorial arrangement with crude protein levels (25% and 35%), microbial phytase (0 and 500 U kg � 1 ), and citric acid (0 and 3%). The 25% crude protein level feed was supplemented with phytase (U kg � 1 )a nd citric acid (%) at the level of 0,0 (C25); 500,0 (T1); 0,3 (T2); 500,3 (T3), and 35% crude protein level feed at 0.0 (C 35); 500,0 (T4); 0,3 (T5) and 500,3(T6 )r espectively. One hundred and twenty juveniles of L. rohita (av. wt. 12.61^13.72 g) were distributed randomly in eight treatments, each of with three replicates. Addition of citric acid in the 25% crude protein feed significantly decreased (Po0.001) feed pH with concurrent decrease in intestinal digesta pH (Po0.001) and increased the bone ash content (Po0.05) by 4.6%. An interaction between citric acid and phytase (Po0.05) was also observed for bone ash content. Increasing the dietary protein content from 25% to 35% signi¢cantly decreased (Po0.01) bone Zn content by14.9%, which was more prominent with the addition of citric acid, resulting in signi¢cant interaction between protein and citric acid (Po0.05), but the bone Cu content was signi¢cantly increased (Po0.01) with increasing dietary protein content. Dietary supplementation of microbial phytase (500 U kg � 1 ) signi¢cantly increased (Po0.05) bone Na, Ca, K, P and Fe contents by 15%, 12.1%, 17.4%, 9.2% and 40.7%, respectively, whereas bone P and Mn content was signi¢cantly increased (Po0.05) by addition of citric acid (3%). Addition of phytase to plant-based diets increased the bioavailability of minerals, thereby increasing bone mineralization. The eiect of phytase was increased because of addition of citric acid (3%).

Effect of dietary microbial phytase supplementation on growth and nutrient digestibility of Pangasius pangasius (Hamilton) fingerlings

A feeding trial was conducted for 60 days to study the effects of exogenous microbial phytase supplementation on the growth and nutrient digestibility of Pangasius pangasius fingerlings. Eight isocaloric and isoprotein experimental diets (35.67% crude protein and 3870 kcal kg−1) were prepared with graded levels of phytase, e.g., 0 (T1), 150 (T2), 250 (T3), 350 (T4), 500 (T5), 1000 (T6) and 2000 (T7) FTU (phytase units) kg−1. Three hundred and fifteen fingerlings of P. pangasius (1.97–2.05 g) were randomly distributed in seven treatments with three replicates each. Maximum weight gain (350.72%), specific growth rate (2.51%), protein efficiency ratio (2.1), apparent net protein utilization (27.85%), energy retention value (88.47%) and feed conversion efficiency were observed in T5 group supplemented with 500 FTU phytase kg−1 diet. Apparent dry matter and protein digestibility in phytase-supplemented groups were significantly (P<0.01) higher at a minimum supplement of 500 FTU kg−1 or higher. Liver alkaline phosphatase activity increased significantly in treatment groups. Supplementation at 500 FTU kg−1 of phytase is optimum in the diet of P. pangasius fingerlings.

Dietary microbial phytase increased the phosphorus digestibility in juvenile Korean rockfish Sebastes schlegeli fed diets containing soybean meal

This study was conducted to evaluate the effects of dietary microbial phytase supplementation on nutrient digestibility, growth performance and body composition in juvenile Korean rockfish fed soybean meal-based diets. Nine experimental diets were formulated to be isonitrogenous and isocaloric to contain 48.6% crude protein (CP) and 15.9 kJ of available energy/g with or without dietary phytase (Natuphos-5000™, BASF, NJ, USA) supplementation. White fish meal (FM) provided 89.1% of the total protein in the basal diet (S 0), in the other eight diets, 30 or 40% FM protein was replaced by soybean meal: 70% FM+30% soybean meal (S 30); 70% FM+30% 1000 U phytase pretreated SM (S 30PP 1000); 70% FM+30% SM+1000 U phytase/kg diet (S 30P 1000); 70% FM+30% SM+2000 U phytase/kg diet (S 30P 2000); 60% FM+40% SM (S 40); 60% FM+40% 1000 U P tre SM (S 40PP 1000); 60% FM+40% SM+1000 U phytase/kg diet (S 40P 1000); and 60% FM+40% SM+2000 U phytase/kg diet (S 40P 2000). After 2 weeks of the adaptation, triplicate groups of 20 fish initially averaging 7.25±0.04 g (mean±S.D.) were randomly distributed into the aquarium and were fed one of the experimental diets for 8 weeks. By the end of the 8-week feeding trial, supplementation of phytase significantly improved the apparent digestibility coefficient (ADC) of phosphorus in rockfish diets ( P<0.05) containing 30% and 40% soybean meal regardless of the level and method of phytase supplementation. Supplementation of phytase significantly increased the ADC of dry matter in diets containing 30% soybean meal ( P<0.05). However, phytase had no influence on growth performance and whole body composition of fish. The pretreatment of soybean meal with 1000 U phytase improved weight gain (WG) when 30% fish meal protein was replaced by soybean meal. Based on the experimental results, we conclude that supplementation of phytase can improve the apparent digestibility coefficient of phosphorus in Korean rockfish.

Dietary microbial phytase supplementation and the utilization of phosphorus, trace minerals and protein by rainbow trout [Oncorhynchus mykiss (Walbaum)] fed soybean meal-based diets

Effects of thermal and enzymatic treatments of soybean meal on apparent absorption of total phosphorus, phytate phosphorus, nitrogen (protein), ash, calcium, magnesium, copper, iron, manganese, strontium and zinc were examined using rainbow trout, Oncorhynchus mykiss (Walbaum), as the test species. Absorption of the test nutrients was estimated using yttrium as an inert non-absorbable indicator. Thermal treatments (microwaving, dry roasting, steam heating, cooking) had no measurable effect on the apparent absorption of phosphorus and other minerals. Phytase supplementation increased the apparent absorption of phosphorus, nitrogen (protein), ash, calcium, magnesium, copper, iron, strontium and zinc in low-ash diets containing soybean meal, but had little effect in high-ash diets containing both soybean and fish meal. In low-ash diets, the apparent absorption of phosphorus increased in accord with the level of phytase added to the diet, from 27% (no phytase added) up to 90% (phytase added, 4000 units kg−1 diet) or 93% (predigested with phytase, 200 units kg−1 soybean meal). In high-ash diets, dietary acidification with citric acid decreased the effect of phytase, whereas in low-ash diets, acidification markedly increased the effect of the enzyme. Excretion of phosphorus in the faeces of fish fed a low-ash diet containing phytase-treated soybean meal was 0.32 g per kg diet consumed, a 95%−98% reduction compared with phosphorus excretion by fish consuming commercial trout feeds.

Reduction of Excretory Phosphorus and Trace Minerals by Dietary Supplementation of Microbial Phytase in Broiler Chicks.

An experiment was conducted to study the effect of microbial phytase on excretory phosphorus (P), copper (Cu), zinc (Zn) and manganese (Mn) in broiler chicks. Male broiler chicks with three replications of 10 chicks each were given free access to the experimental diet from 7 to 21 days of age. The basal diet consisted mainly of corn, soybean meal and defatted rice bran, and contained 0.60% total P, 0.30% non-phytate P, 0.90% calcium, 8.1mg Cu, 82.3mg Zn and 95.3mg Mn per kg of diet, and 0.1% chromium oxide as an indicator. To the basal diet, defluorinated phosphate (0.075 and 0.15% as non-phytate P) or microbial phytase (125, 250 and 500units/kg of diet) was added. The excreta of each replication were collected for the last three days of the experiment, and the retention ratio and excretion of total P, phytate P, Cu, Zn and Mn were calculated.The retention ratio of total P, Cu and Zn increased almost linearly with the increase of supplemented phytase. When 500units/kg phytase were added, total P excretion was reduced by 31%, and the excretion of Cu and Zn was also reduced by 7%, respectively, in comparison with the diet containing 0.45% non-phytate P. However, the excretion of Mn was not affected by the addition of phytase.