Research has demonstrated that phytase is the only enzyme that is able to initiate the release of phosphorus (P) from the phytate molecule, making it available for absorption and utilization (Selle and Ravindran, 2007). The industrial demand for phytases with greater potency in intestinal phytate hydrolysis and better heat stability continues to stimulate the search for new enzyme sources. Enzyme preparations with phytases derived from A. ficuum, Peniophora lycii and E. coli are available commercially. More recently, new microbial 6-phytases produced by synthetic genes, mimicking a gene from C. braakii or isolated from Buttiauxella, were introduced into the market.

1. Comparative efficacy of three phytase products on growth
performance and apparent ileal digestibility of phosphorus
in broiler chickens
R. Aureli1, P. Guggenbuhl1 and J. Broz2
1Research Centre for Animal Nutrition and Health, DSM Nutritional Products France, Village-Neuf, France,
2DSM Nutritional Products Ltd, Basel, Switzerland
INTRODUCTION
Research has demonstrated that phytase is the only enzyme that is able to initiate
the release of phosphorus (P) from the phytate molecule, making it available for
absorption and utilization (Selle and Ravindran, 2007). The industrial demand for
phytases with greater potency in intestinal phytate hydrolysis and better heat
stability continues to stimulate the search for new enzyme sources. Enzyme
preparations with phytases derived from A. ficuum, Peniophora lycii and E. coli are
available commercially. More recently, new microbial 6-phytases produced by
synthetic genes, mimicking a gene from C. braakii or isolated from Buttiauxella,
were introduced into the market.
OBJECTIVE
To compare the efficacy of phytase products derived from either C. braakii, E. coli or
Buttiauxella spp in terms of performance, ileal P digestibility and bone
mineralization in broiler chickens.
CONCLUSIONS
Phytases have a strong potency for improving P availability in
maize/soybean meal based diets for broilers. Irrespective of the
measured parameters, the phytase treatments performed equally to
the PC. All the phytases at the recommended dose were equally
potent in terms of growth performance, ileal digestibility of P and
tibia ash percentage.
Table 1: Composition and nutrient contents of the diets
RESULTS
a,b Means within a row, not sharing a common superscript, are significantly different (p<0.05)
Figure 1: Effect of phytase on WG (g/bird) and FCR (day 1-36) Figure 2: Effect of phytase on AIDP (%) and tibia ash percentage
20th European Symposium on Poultry Nutrition ,24–27 August 2015 , Prague
STARTER (Day 1-21) GROWER (Day 22-36)
Ingredients (%) Diet I/PC Diet II/NC Diet I/PC Diet II/NC
Soybean meal 39.40 38.80 37.20 36.80
Maize 55.00 56.40 55.64 56.20
Soya oil 2.50 1.50 4.00 3.50
DL-Methionine 0.20 0.20 0.10 0.10
CaCO3 0.49 0.69 0.55 0.65
DCP 1.20 0.20 1.20 0.20
Sodium chloride 0.15 0.15 0.15 0.15
Vitamin & mineral premix 1.00 1.00 1.00 1.00
Coccidiostat (Lasalocid) 0.06 0.06 0.06 0.06
Sand 0.00 1.00 0.00 1.24
Titanium dioxide - - 0.10 0.10
Analysed content (g/kg)
Crude protein 229 226 223 211
Metabolizable energy (MJ/kg) 13.3 12.9 13.5 13.3
P total 5.46 3.89 5.44 3.87
Calcium 6.57 5.31 6.62 5.17
MATERIALS & METHODS
Animals: 6 x 20 male broilers (Ross PM3) / treatment
Diets/Treatments : Positive control (PC) diets I adequate in all
nutrient requirements, test diets (Diets II) deficient in nutrients and
energy equivalent to the matrix values determined for PHY1
standard recommended dose (RD), were fed as negative control
(NC) diets. Phytase products were added to NC diet giving 3 test
treatments: PHY1 (C. braakii, Ronozyme® HiPhos (GT)) at 1000
U/kg, PHY2 (E.coli phytase produced by Schizosaccharomyces
pombe) at 500 U/kg, PHY3 (Buttiauxella-phytase) at 500 U/kg
Feeding: pellets, ad libitum; Duration: day 1 to day 35 of bird age;
Parameters: WG, FCR, apparent ileal digestibility of P (AIDP), tibia
ash percentage ; Statistical analysis: ANOVA followed by Newman-
Keuls test (p<0.05)
Reference:
SELLE P.H., RAVINDRAN V.,(2007) Microbial phytase in poultry nutrition. Animal Feed Science and Technology 135: 1–41
a,b,c Means within a row, not sharing a common superscript, are significantly different (p<0.05)