Knowing carbohydrase and phytase effects separately is not sufficient; as they may have contrary effects, for example on feed intake. Both enzymes have to be combined in a specific experimental design to get more insight on the combination effect.
Phosphorus and energy effect
In all trials carried out so far, challenging both energy and phosphorus in the same experimental design, the enzyme combination has been proven to provide at least 1.5 g available phosphorus per kg of feed at the single dosage of 500 FTU/kg in addition to energy (from 85 to 105 kcal/kg in broilers depending on diet type). With the combined enzymatic solution more flexibility in energy reformulation has been gained.
“Rovabio Max is the most effective phytase product because combined with the carbohydrases from Rovabio Excel we remove the "cage" effect and decrease viscosity and thus allow better access to feed phytate. In total, it is 20 enzyme activities in one,” Adisseo says.
All trials have shown that the use of the enzymes leads to substantial feed cost savings. To guarantee phytase action, enough substrate should be present, especially if Rovabio Max is valued up to 2g av. P/kg at the same dosage (500 FTU/kg), as was shown in some trials. Adisseo considers that 1.5g av. P can be released from 2.5g phytic phosphorus – about 60%.
Adisseo says that one single dosage of 500 FTU is effective and profitable since from literature is known that performance response to phosphorus level reaches a plateau and that phytase action is limited by phytate availability.