Comparative efficacy of three phytase products on growth performance and apparent ileal digestibility of phosphorus

in broiler chickensR. 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

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

OBJECTIVETo compare the efficacy of phytase products derived from either C. braakii, E. coli orButtiauxella spp in terms of performance, ileal P digestibility and bonemineralization in broiler chickens.

CONCLUSIONSPhytases have a strong potency for improving P availability inmaize/soybean meal based diets for broilers. Irrespective of themeasured parameters, the phytase treatments performed equally tothe PC. All the phytases at the recommended dose were equallypotent in terms of growth performance, ileal digestibility of P andtibia 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/NCSoybean meal 39.40 38.80 37.20 36.80Maize 55.00 56.40 55.64 56.20Soya oil 2.50 1.50 4.00 3.50DL-Methionine 0.20 0.20 0.10 0.10CaCO3 0.49 0.69 0.55 0.65DCP 1.20 0.20 1.20 0.20Sodium chloride 0.15 0.15 0.15 0.15Vitamin & mineral premix 1.00 1.00 1.00 1.00Coccidiostat (Lasalocid) 0.06 0.06 0.06 0.06Sand 0.00 1.00 0.00 1.24Titanium dioxide - - 0.10 0.10Analysed content (g/kg)Crude protein 229 226 223 211Metabolizable energy (MJ/kg) 13.3 12.9 13.5 13.3P total 5.46 3.89 5.44 3.87Calcium 6.57 5.31 6.62 5.17

MATERIALS & METHODSAnimals: 6 x 20 male broilers (Ross PM3) / treatment

Diets/Treatments : Positive control (PC) diets I adequate in allnutrient requirements, test diets (Diets II) deficient in nutrients andenergy equivalent to the matrix values determined for PHY1standard recommended dose (RD), were fed as negative control(NC) diets. Phytase products were added to NC diet giving 3 testtreatments: PHY1 (C. braakii, Ronozyme® HiPhos (GT)) at 1000U/kg, PHY2 (E.coli phytase produced by Schizosaccharomycespombe) at 500 U/kg, PHY3 (Buttiauxella-phytase) at 500 U/kgFeeding: pellets, ad libitum; Duration: day 1 to day 35 of bird age;Parameters: WG, FCR, apparent ileal digestibility of P (AIDP), tibiaash 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)