Phytate as an anti-nutrient for poultry and swine

Hello Rafael, Good to talk to you again. There are several questions here so I'll try to answer them one by one: 1) how do you come to those values - matrix values - you recommend. Mtrix recommendation are usually calculated in a dose response trial with diets with different levels of P. Based on the performance of the treatment with phytase inclusion, the P release is calculated. Calculation for other nutrients depends a lot on each supplier as they are much more dufficult to be done in a straitforward trial. 2) are these values for avP/dP and Ca very different for poultry than for pigs? In our research we have't seen big differences in phytase effectiveness between growing/finisher pigs and broilers. Expectoins would be layers, where phytase is more efficient, and piglets, where phytate concentration in the diet become a limitation. 3) would you say that phytases, based on the phytate nature - at same level of phytate - would have a different efficiacy? Yes, different phytases will have different efficacies in vivo. Not all phytases are the same. Tiago Tedeschi dos Santos

Thanks once more Tiago, very clear and good answers though the last one, due to my lack of good explanation, is not what I asked; indeed I also think phytases have different efficiacies. But my last question, here I try again: considering the same phytase - the one you talk about, let´s say - and same phytate level, would you expect even if from a practical point of view you don´t recommend, that the efficiency differs in P release?. Thanks again and greetings from Madrid.