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Carcass characteristics of broilers at 42 days receiving diets with phytase in different energy and crude protein levels
Nagata, Adriano Kaneo;Rodrigues, Paulo Borges;Alvarenga, Renata Ribeiro;Zangeronimo, Márcio Gilberto;Donato, Daniella Carolina Zanardo;Silva, José Humberto Vilar da;
Ciência e Agrotecnologia , 2011, DOI: 10.1590/S1413-70542011000300020
Abstract: the aim of this study was to evaluate carcass characteristics and quality of breast meat after the inclusion of phytase in broiler diets with different levels of apparent metabolizable energy (amen) corrected for nitrogen and reduced crude protein (cp) supplemented with essential amino acids following the concept of ideal protein. a total of 1,500 cobb broilers from 22 to 42 days (initial weight of 833 ± 7 g and final weight of 2741 ± 48 g) were distributed in completely randomized design in a factorial 3x3+1 experiment (three levels of amen - 2,950; 3,100 and 3,250 kcal/kg - and three levels of cp - 14, 16 and 18% - and an additional treatment - control without phytase, with 3,100 kcal/kg eman, 19.2% pb and 0.4% available phosphorus), in six replications of 25 birds each. at the end of the trial, two birds of each experimental unit were slaughtered in order to measure carcass yield and yields of parts and to determine the chemical composition of the breast meat. the levels of amen and cp of diets with phytase influenced (p<0.05) the carcass, breast and abdominal fat yield and humidity, protein and fat percentage in the pectoralis major muscle of the birds. the levels of 3,100 kcal amen/kg and 18% cp showed higher carcass and breast yield and lower abdominal fat deposition, although with higher fat percentage in the breast meat. it was concluded that the manipulation of the energy levels of diets with reduced crude protein supplemented with amino acids and phytase influenced the yields of parts of carcass and the breast meat quality of the broilers at 42 days.
Performance, Bone Parameters and Phosphorus Excretion of Broilers Fed Low Phosphorus Diets Supplemented with Phytase from 23 to 40 Days of Age  [PDF]
A.E. El-Sherbiny,H.M.A. Hassan,M.O. Abd-Elsamee,A. Samy
International Journal of Poultry Science , 2010,
Abstract: An experiment was conducted using 300 growing Ross 308 broilers from 23 to 40 days of age. Six dietary treatments were formulated. A basal diet contained 1.48% Dicalcium Phosphate (DCP) was used as a control diet (diet 1). Diets 2 and 3 contained 50% and 25% of the DCP of diet 1 (0.74 and 0.37%, respectively), while diet 4 was formulated without DCP. Diets 3 and 4 were fed without or with supplemented phytase enzyme (500 U/kg). Every dietary treatment was fed to 5 replicates (10 chicks each). The results showed no significant differences between birds fed diets containing 1.48 % DCP or 0.74% DCP on BWG, FI and FCR. Reducing dietary DCP level to 0.37% slightly decreased BWG compared with birds fed 0.74% DCP with inferior value of FCR. When DCP was removed from the diet BWG significantly (p<0.01) decreased and FCR recorded worth value. Addition of 500 U phytase/kg to diet 3 of 0.37% DCP significantly enhanced BWG (p<0.01), feed intake and FCR (p<0.05). Addition of phytase to the diet of no DCP did improve neither BWG nor FCR. Decreasing dietary DCP did not significantly affect length, weights and width of tibia either with or without phytase supplementation. However, birds fed the highest level of dietary DCP showed the highest values of tibia weight and length among the different groups. Tibia breaking strength (kgf) significantly (p<0.001) decreased as dietary DCP level decreased. Addition of phytase significantly (p<0.001) improved tibia breaking strength and tibia ash %. Addition of phytase to diet of low DCP did increase tibia Ca and P to reach values comparable with those of the control diet. Decreasing dietary DCP showed significant (p<0.001) decrease in the excreted Ca and P. Addition of phytase to diets of low or no DCP also decreased (p<0.001) the excreted Ca and P. This means that phytase increased the utilization of dietary Ca and P. The excreted Ca and P decreased by 41.22% and 55.26%, respectively, when birds were fed diet of no DCP compared to those fed the control diet. Also, addition of phytase enzyme to diets of low or no DCP decreased the excreted percentage of Ca and P. It could be concluded that reducing dietary P level and using phytase enzyme could be used to limit quantity of P excreted from broilers. This reduce such impact in environmental pollution.
Effect of dietary phytase suplementation on the performance, bone densitometry, and phosphorus and nitrogen excretion of broilers
Assuena, V;Junqueira, OM;Duarte, KF;Laurentiz, AC;Filardi, RS;Sgavioli, S;
Revista Brasileira de Ciência Avícola , 2009, DOI: 10.1590/S1516-635X2009000100005
Abstract: this experiment was carried out to evaluate the effects of the inclusion of different levels of phytase on broiler performance, bone densitometry, and phosphorus and nitrogen excretion. nine hundred and sixty one-day old broilers, 50% males and 50% females, were distributed in a completely randomized experimental design into five treatments and six replicates 32 birds each. the treatments consisted of a control diet and four diets with the addition 25, 50, 75, and 100 g/ ton of phytase (250, 500, 750 and 1000 ftu of phytase/kg fed). diets were formulated to contain equal nutritional levels, and considered the phytase product nutritional levels. in general, the addition of phytase resulted in a linear decrease in broiler performance. however, the performance results obtained with the level of 250 ftu phytase/kg feed were not different from the control treatment. the best bone density results were observed in the control treatment, with no phytase. the results of this experiment indicate that the nutritional matrix of the phytase product needs to be reviewed when added in levels higher 250 ftu/kg to broiler diets.
Effect of Adding Phytase to Broiler Diets Containing Low and High Phytate Phosphorus: 1. Performance, Phytate P Hydrolysis, Tibia Ash, Litter Phosphorus and Ca and P Digestion and Retention  [PDF]
M.K. Manangi,J.S. Sands,C.N. Coon
International Journal of Poultry Science , 2009,
Abstract: A 42 d broiler experiment was conducted to determine the effect of added Escherichia coli phytase (Phyzyme-XP 5000G) to low and high phytate P (PP) diets on performance and nutrient digestibility. The experiment consisted of 12 treatments with 2 levels of PP: Low-Phytate (LP) group-0.24% and High-Phytate (HP) group-0.32%. Both LP and HP groups had respective Positive Controls (PCs) with 0.39% in the starter and 0.29% NPP in the grower, respectively and 5 basal diets with graded levels (0, 250, 500, 750 and 1000 FTU’s/kg diet) of added phytase. The HP diets contained additional PP because canola and rice bran were substituted for part of the corn and soybean meal. A significant (p<0.001) phytase effect was found for Body Weight Gain (BWG) Feed Intake (FI) and Feed:Gain (F:G) ratio on d 42 and ileal P digestibility and % tibia ash for both LP and HP groups on d 42. Supplementation of 250 FTU’s phytase/kg diet for both LP and HP basal diets produced equivalent body weights (p>0.05) to comparable respective PCs. Supplementing 500 FTU’s phytase/kg diet in both LP and HP groups resulted in a comparable (p>0.05) % tibia ash to respective PC groups. The litter Total Dissolved P (TDP) and Water-Soluble P (WSP) of pens from broilers fed either the LP or HP basal diets with increasing concentrations of phytase were not significantly different (p>0.05) compared to the respective PCs. The research shows that adding feed phytase does not necessarily mean that TDP and WSP will be reduced. The P equivalency determined from 42d ileal digesta for added phtase with the LP and HP diets showed that broilers fed the HP diet with 1000 FTU phytase provided 0.17% digestible P compared to 0.13% digestible P from the LP diet. In order to decrease P excretion in broilers, added feed phytase should be considered equal to feed phosphates for providing available P in the gastrointestinal tract and the combination needs to be low enough for optimum performance and retention.
Effect of Phytase on Ileal Amino Acid Digestibility, Nitrogen Retention and AMEn for Broilers Fed Diets Containing Low and High Phytate Phosphorus  [PDF]
M.K. Manangi,J.S. Sands,C.N. Coon
International Journal of Poultry Science , 2009,
Abstract: A 42 d broiler experiment was conducted to determine the effect of added Escherichia coli phytase (Phyzyme-XP 5000G) to low and high phytate P (PP) diets on performance and nutrient digestibility. The experiment consisted of 12 treatments with 2 levels of PP: Low-Phytate (LP) group-0.24% and High-Phytate (HP) group-0.32%. Both LP and HP groups had respective Positive Controls (PCs) with 0.39% in the starter and 0.29% NPP in the grower, respectively and 5 basal diets with graded levels (0, 250, 500, 750 and 1000 FTU’s/kg diet) of added phytase. The HP diets contained additional PP because canola and rice bran were substituted for part of the corn and soybean meal. GE retention was significantly improved 6% percentage points for 42 d broilers fed either LP or HP diets with added phytase however a significant interaction indicated the improvement in energy retention caused by phytase was primarily from the broilers fed the HP diet. Overall there was no significant main effect of phytase on GE retention of 21 d broilers but the energy retention of HP diet was significantly less than for LP fed broilers and broilers fed the LP diet showed a significant improvement an interaction suggested the phytase would only benefit broilers fed the LP diet. The ileal % digestibility of threonine, tryptophan and serine were affected by PP levels, phytase and the interaction of PP and phytase for 21 d broilers, whereas cystine was the only amino acid to show all three main effects for 42 d broilers. In general, the interaction of phytase and PP for ileal digestibility of specific amino acids was caused by a lack of positive response of phytase when added to the HP diet for 21 d broilers, whereas phytase showed an influential trend of improving ileal digestibility of all amino acids (p = 0.1284) in either of the HP or LP diets for the older 42 d broiler. The slight improvement of ileal digestible amino acids seemed to correlate with a 6.2 percentage point improvement in % ileal N digestibility for 42 d broilers fed either the LP or HP diets. Broilers fed the LP PC diet had a higher % ileal nitrogen and energy digestion than broilers fed the HP PC diet at 21 d but there was no difference in 42 d broilers fed the two different PP diets. In summary adding phytase to broiler diets improved energy utilization by 2.1-4.9% for both LP and HP fed broilers and an 1.9-6.1% improved ileal % tAA digestibility for LP fed broilers.
Sunflower meal for broilers of 22 to 42 days of age
Araújo, Lúcio Francelino;Araújo, Cristiane Soares da Silva;Petroli, Natália Barros;Laurentiz, Antonio Carlos de;Albuquerque, Ricardo de;de Trindade Neto, Messias Alves;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011001000011
Abstract: the objective of the present experiment was to evaluate the inclusion of sunflower meal in diets formulated on total or digestible amino acid basis fed to broilers of 22 to 42 days of age. nine hundred and sixty birds were distributed in a completely randomized experimental design in a 2 × 2 factorial arrangement (two formulation criteria - digestible or total amino acids; two sunflower meal inclusion levels - 0 or 15%), with six replicates of 40 broilers each. performance (weight gain, feed intake and feed conversion) and data from carcass characteristics (eviscerated carcass and commercial cuts) were evaluated. on day 42, six birds from each pen were sacrificed to determine digesta viscosity, and litter samples from each replicate pen were collected to determine litter moisture. the inclusion of 15% sunflower meal in broiler diets formulated on total amino acid basis worsens feed conversion ratio. diets formulated on digestible amino acid basis are adequate when alternative feedstuffs, such as sunflower meal, are included. the use of sunflower meal in the diet does not influence carcass and cuts yields, but digesta viscosity increases when 15% of that feedstuff is included in the diet.
Effect of Phytase on the Sodium Requirement of Starting Broilers 1. Sodium Bicarbonate as Primary Sodium Source  [PDF]
S.D. Goodgame,F.J. Mussini,C. Lu,C.D. Bradley
International Journal of Poultry Science , 2011,
Abstract: Recent work has indicated that phytase enzymes may influence Sodium (Na) metabolism in the chick but to date no work has conclusively demonstrated that the Na requirement of the chick for live performance is influenced by phytase supplementation. In this study male broilers were fed diets with Na levels ranging from 0.10-0.28% using sodium bicarbonate as the primary source of supplemental Na. Diets were supplemented with no phytase, 500 FTU/kg (1x) or 2,000 FTU/kg (4x) of phytase. When phytase was added the dietary Ca and Nonphytate P (NPP) were adjusted in accordance with anticipated release of these minerals. For 1x phytase the Ca and NPP were reduced 0.10% each and for 4x phytase were reduced by 0.20% each. The combination of seven Na levels and three phytase treatments resulted in 21 dietary treatments, each of which was fed to six replicate pens of five male chicks housed in electrically heated battery brooders with wire floors. Experimental diets and tap water were provided for ad libitum consumption from day of hatch to 18 d. At 16 d of age excreta from each pen was collected and freeze dried to determine moisture content and the excreta analyzed to determine amounts of Ca, P and Na. There were no significant differences in Body Weight (BW), Feed Conversion (FCR), Feed Intake (FI), fecal moisture (FH2O), or mortality of broilers fed diets with different levels of phytase indicating that the dietary adjustment in NPP and Ca levels for the addition of the phytase did not adversely affect performance of the birds. The dietary Na level significantly affected BW, FCR, FI or FH2O. There were no significant interactions of dietary Na and level of phytase supplementation. Regression analysis showed an overall estimate of 0.180.01% Na for BW and 0.190.01% Na for FCR. There was little indication that the Na requirement was affected by phytase. The level of phytase and Na in the diet had significant effects on excreta levels of P, Ca and Na. The use of lower dietary levels of NPP and Ca in association with the addition of the phytase resulted in significant reduction in excreta levels of these minerals, but had no significant effect on levels of excreted Na. Increasing the dietary Na level significantly affected the levels of all three minerals in the excreta. Although the dietary Na level had significant effects on both excreta P and Ca, these followed no consistent trends with no significant difference in Ca or P excretion between chicks fed diets with the lowest and highest Na levels. There were significant interactions between dietary Na levels and leve
Nitrogen, calcium and phosphorus balance of broilers fed diets with phytase and crystalline amino acids
Gomide, Elisangela Minati;Rodrigues, Paulo Borges;Zangeronimo, Márcio Gilberto;Bertechini, Ant?nio Gilberto;Santos, Luziane Moreira dos;Alvarenga, Renata Ribeiro;
Ciência e Agrotecnologia , 2011, DOI: 10.1590/S1413-70542011005000003
Abstract: the objective of this study was to evaluate the effect of reduced-crude protein (cp) and available phosphorus (ap) diets, added with phytase and amino acids for broilers in the growing (14 to 21 days old) and retirement (35 to 42 days) phases on nitrogen, potassium and phosphorus balance. ninety cobb broilers were distributed in a completely randomized design with three treatments and six replications with five and three birds per experimental unit in the growing and retirement phases, respectively. diets were elaborated to contain reduced cp and ap levels (19 and 17% cp in the growing phase, with 0.34% ap; and 18 and 16% cp in the retirement phase, with 0.30% ap), supplemented with crystalline amino acids and 500 ftu of phytase/kg diet. these were compared to a control diet (21% cp and 0.46% ap for growing phase and 19% cp and 0.40% ap for retirement phase). the reduction of cp in four percentual units reduced the n excretion and increased the retention of this element, showing that the phytase had no influence on n balance when used the crystalline amino acids in the diets. the phytase reduced the p excretion and increased the retention ones. the potassium excretion decreased in reduced-cp diets, but this excessive reduction decreased the retention of this element, except in the retirement phase. it was concluded that the reduced-cp and ap diets, supplemented with phytase and amino acids, are efficient in reducing the pollutant power of the broilers excrements in the growing and retirement phases of production.
Diet supplementation with phytase on performance of broiler chickens
Lelis, Guilherme Rodrigues;Albino, Luiz Fernando Teixeira;Calderano, Arele Arlindo;Tavernari, Fernando de Castro;Rostagno, Horacio Santiago;Campos, Anastácia Maria de Araújo;Araújo, Wagner Azis Garcia de;Ribeiro Junior, Valdir;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000400014
Abstract: the assay was carried out to determine the effect of phytase supplementation on performance of broilers from 1 to 21 and 1 to 40 days of age. twelve hundred and fifty male broilers (ross) were distributed in a randomized experimental design, with five treatments, 10 repetitions and 25 birds per experimental unit. the treatments consisted of evaluating the phytase supplementation in diets with reductions in nutritional levels, compared with the positive control. the nutrient contents in negative controls one and two were reduced progressively and these diets were supplemented with phytase levels of 250 and 500 ftu/kg of the diet, respectively. two diets were formulated: pre-starter/starter, 1-21 days, and growth/finishing, from 21 to 40 days). in both phases, with the phytase supplementation in diets that had their nutritional levels reduced (negative control one + 250 ftu and negative control two + 500 ftu), feed intake, weight gain and feed conversion of the birds were similar to the positive control. in the period from 1 to 40 days of age, with the diets supplemented with phytase, the productive efficiency index of the birds was similar to that of the positive control group. supplementation with 250 ftu/kg and 500 ftu/kg phytase in diets with reduced nutritional levels improved broiler performance, resulting in parameters similar to those shown by broilers fed with the diet with normal levels of nutrients.
Nonphytate Phosphorus Requirement and Phosphorus Excretion of Broiler Chicks Fed Diets Composed of Normal or High Available Phosphate Corn as Influenced by Phytase Supplementation and Vitamin D Source  [PDF]
F. Yan,P.W. Waldroup
International Journal of Poultry Science , 2006,
Abstract: A study was conducted to evaluate the ability of young broiler chicks (0-3 wk) to utilize the P provided by a high available phosphate corn (HAPC) in comparison with yellow dent corn (YDC) and to determine the extent to which microbial phytase supplementation and use of 25-hydroxycholecalciferol (25-OH-D3) in the diet could reduce the requirements for P and subsequently reduce P excretion. Diets were prepared using either YDC or HAPC, which contained about the same total P but differed in phytate-bound P content. Within each corn type, diets were fortified with either vitamin D3 or 25-OH-D3 at the rate of 68.9 μg/kg diet. Treatment diets were prepared by varying the amount of dicalcium phosphate and ground limestone, and ranged from 0.09 to 0.50% nonphytate P (nPP) for YDC diets and 0.18 to 0.50% nPP for HAPC diets. Sublots of each diet were supplemented with 1000 units/kg phytase. Each diet was fed to four replicate pens of six male broilers of a commercial strain from 1 to 21 d of age. After factorial analysis, nonlinear regression analysis was conducted to estimate a nPP level sufficient for maximum body weight gain or tibia ash percentage for each corn type as influenced by phytase supplementation or use of 25-OH-D3. For broilers fed YDC diets, the estimations for maximum tibia ash were 0.40, 0.35, 0.32, and 0.27% nPP for diets supplemented with D3, D3 + phytase, 25-OH-D3, and 25-OH-D3 + phytase respectively. For broilers fed HAPC diets, substitution of D3 with 25-OH-D3 had no significant effect on tibia ash percentage and the inflection points for maximum tibia ash were 0.39 and 0.33% with and without phytase supplementation respectively. These nPP levels were sufficient to support body weight, feed conversion, or livability. The nPP in HAPC was equivalent in bioavailability to the P from dicalcium phosphate. In the absence of phytase, dry feces of broiler chicks fed YDC diets at the NRC (1994) recommended level of 0.45% nPP contained 1.19% P, whereas at the above inflection points, the fecal P content was 1.06, 1.11, 0.98, and 0.78% for chicks fed YDC diets supplemented with D3, D3 + plus phytase, 25-OH-D3, and 25-OH-D3 + phytase respectively. For chicks fed HAPC diets at the inflection points, the fecal P content was 0.84 and 0.68% with and without phytase supplementation respectively. Thus fecal P output can be reduced significantly while maintaining optimum live performance and bone mineralization by supplementation with microbial phytase, addition of 25-OH-D3, use of HAPC, reduction in dietary nPP level, or combinations of the above.
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