The effects of phytase supplementation on nutrient digestibility, plasma parameters, performance and carcass traits of pigs fed diets based on low-phytate barley without inorganic phosphorus

2006 ◽  
Vol 86 (2) ◽  
pp. 245-254 ◽  
Author(s):  
P. A. Thacker ◽  
B. G. Rossnagel ◽  
V. Raboy

A total of 80 crossbred pigs (25.5 ± 2.6 kg) were assigned to one of eight dietary treatments. A positive control, based on Harrington barley, was formulated to meet requirements for total phosphorus. Three experimental diets (low in total phosphorus) were formulated based on either Harrington barley (0.28% phytate phosphorus) or the low phytate genotypes LP422 (0.14% phytate phosphorus) and LP 635 (0.09% phytate phosphorus). The four diets were fed with and without 1000 FTU kg-1 phytase. Calcium and phosphorus digestibility were significantly higher (P < 0.05) as a result of supplementation with phytase. For the barley diets formulated without dicalcium phosphate, calcium digestibility averaged 69.6, 73.3 and 72.2% while phosphorus digestibility averaged 36.5, 50.5 and 57.7% for pigs fed the Harrington, LP 422 and LP 635 diets, respectively. The addition of phytase to the diet consistently reduced the percentage of phosphorus excreted in feces and fecal phosphorus excretion declined as the level of phytate in the barley declined. The addition of phytase tended to improve weight gain (P < 0.10) and significantly improved feed conversion (P < 0.05). For pigs fed the barley diets formulated without dicalcium phosphate, daily gain averaged 0.90, 0.99 and 1.01 kg d-1 while feed conversion averaged 2.70, 2.39 and 2.38 for the Harrington, LP 422 and LP 635 diets, respectively. The overall results of this experiment indicate that the performance of pigs fed diets containing low-phytate barley formulated without a source of inorganic phosphorus is at least equal to that of pigs fed diets containing normal-phytate barley and inorganic phosphorus. In addition, the increased availability of organic phosphorus reduced the amount of phosphorus excreted thus reducing the amount of phosphorus that can potentially pollute the environment. Key words: Low phytate barley, phytase, pigs, performance, digestibility

2019 ◽  
Vol 40 (2) ◽  
pp. 767
Author(s):  
Gabriel Villela Dessimoni ◽  
Nilva Kazue Sakomura ◽  
Daniella Carolina Zanardo Donato ◽  
Fábio Goldflus ◽  
Nayara Tavares Ferreira ◽  
...  

Although phytase has been researched, new enzymes have been produced, leading to different animal responses. In this scenario, the present study proposes to evaluate the inclusion of a bacterial phytase produced by Escherichia coli in broiler diets based on corn and soybean meal, with or without nutrient reductions, on the performance, nutrient digestibility, phosphorus bioavailability, and bone minerals of those animals and on the economic viability of this practice. A total of 896 male broiler chickens were distributed into 32 experimental units, each housing 28 broilers. The experiment was set up as a completely randomized design with four treatments (Positive Control (PC)- diet meeting the nutritional requirements of the broiler chickens; Negative Control (NC) with reductions of 100kcal/kg of ME, 0.14% avP and 0.11% tCa; NC + phytase (500 FTU/kg); PC + phytase (500FTU/kg)) and 8 replicates. Phytase increased (p < 0.05) feed intake and body weight gain and improved feed conversion ratio in starter (1 to 21 days) and total (1 to 42 days) phases, respectively, compared with Negative Control diet without supplementation. The Negative Control + phytase diet also led to a feed intake similar to Positive Control in the starter and total phases. The inclusion of phytase without nutrient reductions improved (p < 0.05) feed conversion ratio in the starter phase, compared to Positive Control diet. There was an increase (p < 0.05) in the digestibility of dry matter, crude protein and phosphorus and in apparent digestible energy in the Negative Control + phytase diet compared to the Negative Control diet. Phytase supplementation increased (p < 0.05) the digestibility of crude protein, calcium and phosphorus, and apparent digestible energy compared to Positive Control diet. Ash, phosphorus, and calcium contents were higher in the Negative Control + phytase diet compared with those observed in the Negative Control diet without enzyme (p < 0.05). The Positive Control + phytase diet provided higher ash contents (p < 0.05), but calcium and phosphorus deposition was similar to those obtained with Positive Control diet. Phytase inclusion allows for a reduction in the diet cost per ton of produced feed. In conclusion, dietary supplementation with bacterial phytase produced from Escherichia coli for broiler chickens is recommended, as it provided increases in production performance, nutrient digestibility, and energy metabolizability and a reduction in the diet cost.


2017 ◽  
Vol 75 (10) ◽  
pp. 2291-2298 ◽  
Author(s):  
Cui Lijuan ◽  
Li Wei ◽  
Zhou Jian ◽  
Zhang Yan ◽  
Zhang Manyin ◽  
...  

Substrate adsorption is one of the main processes by which redundant phosphorus is removed from wastewater in surface flow constructed wetlands (SFCWs). The physical properties of the substrate, such as depth and particle size, will influence the amount of phosphorus adsorption. This study was carried out in a long-running intermittent inflow constructed wetland that covered a total area of 940.4 m2 in the Shunyi District of Beijing, China. We investigated how the concentrations of four phosphorus fractions, namely calcium phosphate (CaP), iron phosphate (FeP), adsorbed phosphorus (AdsP), and organic phosphorus (OP), varied between the surface (0–10 cm) and subsurface (10–20 cm) substrate and among the different substrate particle sizes. The total phosphorus concentrations in the substrate ranged from 154.97 to 194.69 mg/kg; CaP accounted for more than 80% of the total phosphorus content. The concentrations of OP were significantly higher in the surface layer than in the subsurface layer, but the concentrations of inorganic phosphorus were not significantly different between the two layers. The CaP, AdsP, and OP adsorption capacities were greater for small-sized substrate particles than for large-sized substrate particles. The results from this study provide a theoretical basis for the construction of constructed wetlands.


1961 ◽  
Vol 12 (1) ◽  
pp. 111 ◽  
Author(s):  
SM Bromfield

Faeces from sheep grazing naturalDanthonia pastures and improved subterranean clover pastures have been analysed for total phosphorus and inorganic phosphate over a period of 2 years. Both total and inorganic phosphorus contents (milligrams P per gram) varied widely with type of pasture and with season. The variation in organic phosphorus content (by difference) remained, relative to total phosphorus, fairly constant throughout. Total phosphorus content varied from 1.8 to 17 mg P/g whilst organic phosphorus varied from 1.5 to 4.0 mg P/g. Sheep grazing the improved pastures voided approximately 2.5–3 lb P as inorganic phosphate and 0.5–0.75 lb P as organic phosphorus per sheep per year. The inorganic phosphate was readily soluble in acid but not in water and was readily available to wheat grown in pot culture. The organic phosphorus was not readily available to plants and was not rapidly mineralized to inorganic phosphate. The contribution faecal phosphorus makes to the nutrition of pastures and to the reserve of soil organic phosphorus is briefly discussed.


1959 ◽  
Vol 39 (1) ◽  
pp. 20-26 ◽  
Author(s):  
G. W. Boswall ◽  
W. A. Delong

A mild laboratory procedure, employing oxine in a water-benzene system, for the release of organic phosphorus from two unimproved pasture soils differing widely in total phosphorus, ratio of organic to inorganic phosphorus, pH, calcium content and clay content, is described.Data are presented showing the influence of the following factors on the amount of phosphorus released: soil to water ratio, the pH of the extraction medium, and the soil pretreatments. Under the more favourable conditions the two soils released 75 and 86 per cent of their total organic phosphorus respectively.


Author(s):  
K. Kozlowski ◽  
L. Nollet ◽  
A. Lanckriet ◽  
E. Vanderbeke ◽  
P. Mielnik ◽  
...  

AbstractThis study evaluated the effects of three different thermostable phytase variants, based on the AppA gene from E. coli (AppAT1, AppAT2 and AppAT3) on growth performance, nutrient digestibility and bone mineralisation in broiler chickens at inclusion levels of 250 and 500 FTU/kg. The eight treatment groups included a positive control (PC) which was sufficient in Ca and P, a negative control (NC, the same basal formulation as the PC, but reduced in Ca and P), and NC supplemented with AppAT1 at 250 and 500 FTU/kg (AppAT1-250 and AppAT1-500), AppAT2 at 250 and 500 FTU/kg (AppAT2-250 and AppAT2-500) and with AppAT3 at 250 and 500 FTU/kg (AppAT3-250 and AppAT3-500). Over the entire feeding period, body weight (BW) and average daily gain (ADG) were significantly higher in the PC group, with all phytase supplemented groups being statistically the same, compared to the NC group. Feed conversion (FCR) for the PC-fed birds (1.479) was significantly (P&lt;0.05) better compared to the NC birds (1.582) and those fed the AppAT3-250 diet (1.523). Reduced levels of Ca and P in the NC group led to significantly (P&lt;0.05) lower tibia ash (40.9%) compared to the PC group (47.4%). Birds fed the phytase diets had significantly higher tibia ash compared to the NC birds, with those from the AppAT2-500 and AppAT3-500 groups being statistically the same as the PC group. Diets AppAT1-500, AppAT2-250, AppAT2-500 and AppAT3-500 significantly increased Ca digestibility compared to the NC. Apparent total track digestibility (ATTD) of P was improved for AppAT1-500 and AppAT2-250. The ATTD of Ca and P for all of the phytase supplemented groups reached the same level of the PC and AppAT1-500 group. It was concluded that adding any of the phytases tested, especially when included at 500 FTU/kg to a feed reduced in Ca and P, led to improved performance and bone mineralisation back to the same levels as seen for the Ca and P sufficient diet.


1956 ◽  
Vol 28 (1) ◽  
pp. 90-104
Author(s):  
Armi Kaila

In the present paper results are reported concerning the total content as well as solubility of organic and inorganic phosphorus in 122 peat samples which were collected from various depths of 30 peat lands. The total phosphorus content of all the samples was rather low and no regularity in the influence of the depth upon this quantity could be demonstrated. There seemed to be some tendency to an increase in the P-content with increasing depth in the peat lands of lower quality. In peat lands of higher quality the opposite often held true. A large part of the phosphorus occurred in organic form, and, almost without exception, this percentage of total phosphorus increased with the depth: in undecomposed plant material this proportion was about 50—60 per cent, in the surface layers 70 per cent, on the average, in deposits deeper than 50 cm seldom less than 80 per cent and it could even reach 95 per cent. 1he amount of organic phosphorus expressed as a percentage of organic dry matter was low in most of the samples and although it tended to increase with the depth only in 11 of all the 122 samples values higher than 0.1 per cent were obtained. Even if an allowance is made for the conditions prevailing in peat lands these low percentages of organic phosphorus indicate that, from the microbiological point of view, no rapid mineralization of the organic phosphorus compounds is probable. The inorganic phosphorus content was low and tended to decrease from the surface to deeper layers. The solubility of inorganic phosphorus, however, dropped much more drastically. Thus in the deeper layers the amount of easily extractable inorganic phosphorus could be negligible. The solubility of organic phosphorus also impaired with the depth. The phosphorus economy of peat lands was discussed on the basis of the results obtained.


2006 ◽  
Vol 86 (4) ◽  
pp. 501-510 ◽  
Author(s):  
C. M. Nyachoti ◽  
J. S. Sands ◽  
M. L. Connor ◽  
O. Adeola

Effect of an Escherichia coli derived, 6-phytase on nutrient digestibility and sow and litter performance were investigated. Six (exp. 1) or eight (exp. 2) sows per diet were randomly assigned to a positive control (PC), a negative control (NC) with reduced non-phytate phosphorus (P), NC + 500 FTU kg-1, or NC + 1000 FTU kg-1 diet from day 60 of gestation to day 22 postpartum. Diets in exps. 1 and 2 were based on corn and wheat, respectively. Energy, N, calcium (Ca), and P digestibilities were determined between days 73 to 77 (Period 1), 104 to 106 (Period 2) of pregnancy, and days 16 to 20 postpartum. Sow and litter performance were monitored. During gestation, phytase at 500 FUT kg-1 did not affect nutrient digestibility in exp. 1 but improved (P < 0.05) DE and digestibilities of DM, energy, N, and P in exp. 2. Increasing phytase to 1000 FTU kg-1 reduced (P < 0.05) digestibilities of energy and N (exp. 1). In both experiments, digestibilities of N, Ca, and P were higher (P < 0.05) in period 2 than period 1. During lactation, supplementing the NC diet with 500 FTU kg-1 only improved (P < 0.05) DE and Ca and P digestibility in exp. 1 and DE and digestible P in exp. 2. Compared with NC, P digestibility and digestible P were higher (P < 0.05) in the NC + 1000 FTU kg-1 diet in both experiments. Sow and piglet performance was unaffected by diet in both experiments. In conclusion, P digestibility was greater between days 104 and 106 of gestation than between days 73 and 77 of gestation and phytase improved P digestibility during lactation but this effect was not consistent during gestation in both experiments. Key words: Digestibility, phytase, phosphorus, sows


2000 ◽  
Vol 48 (5) ◽  
pp. 597 ◽  
Author(s):  
B. Hawkins ◽  
P. J. Polglase

Mature and senescent foliage were sampled from 15 species of Eucalyptus, covering three subgenera, Symphyomyrtus, Monocalyptus and Corymbia, under non-limiting availability of water and nutrients (effluent-irrigated plantation). Concentrations of total phosphorus in mature foliage were relatively high for Eucalyptus (range 1.6–3.1 mg g–1), inorganic phosphorus accounting for 60–79% of total phosphorus. Foliar concentrations of total and inorganic phosphorus in Monocalyptus were about twice as much as in Symphyomyrtus. Concentrations of nitrogen did not differ amongst subgenera. About 50% of leaf nitrogen was resorbed during senescence. In contrast, about 11–24% of phosphorus was resorbed, of which about 48–77% was derived from hydrolysis of organic phosphorus. There were no significant differences amongst subgenera in resorption of either nitrogen or phosphorus. Despite significant variability in nutritional characteristics within subgenera, we conclude that Monocalyptus has a greater capacity to accumulate foliar phosphorus (as inorganic phosphorus) than Symphyomyrtus, but that Symphyomyrtus has a greater phosphorus-use efficiency (ratio of growth to foliar phosphorus). Foliar inorganic phosphorus appears to be easily manipulated by nutrient amendment whereas nitrogen is highly resistant. Resorption efficiency of phosphorus (proportion of total phosphorus resorbed) is decreased under high availability of soil phosphorus.


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