The global price of inorganic phosphorus has increased significantly due to regional and international supply chain disruptions as a result of the Covid-19 epidemic. Dr Jae Cheol Kim of AB Vista reports an unpublished feeding trial conducted by a broiler integrator in Southeast Asia. It shows super-dosing with an enhanced E.coli phytase in normal or low phosphorous or low calcium corn-soy diets can significantly reduce or even completely replace inorganic phosphorous with no loss of performance.
The study used 2400 newly hatched commercial straight-run broiler chicks (Lohman Indian 85 River) randomly allocated into 5 dietary treatments with 16 replicate pens per treatment and 30 chicks per floor pen.
The positive control diets were corn-soybean meal-based diets containing 0.40/0.80%, 0.35/0.70%, and 0.30/0.60% available phosphorus (avP) and total calcium (Ca), respectively from 0-10, 10-25, and 26-42 days post-hatch (PC). An additional PC diet (PC++) containing extra avP and Ca (+0.05% avP/+0.1% Ca) to that of PC was included to test if avP and Ca in the PC diet were limiting.
Three test diets were formulated with 500, 1000, and 1500 FTU/kg of phytase assigned respectively an avP matrix of 0.15, 0.19, and 0.23% and a fixed Ca matrix of 0.15%. Analysed phytate phosphorus contents of the experimental diets were 0.25-0.26%. Based on the formulation, inclusion of monocalcium phosphate (MCP) in each phase diet and total use of MCP in each treatment are presented in Figure 1.
As it can be seen MCP inclusions in all diets were significantly reduced, and MCP was completely excluded in the grower and finisher diets with 1500 FTU and the finisher diets with 1000 FTU enhanced E. coli phytase (Quantum Blue, AB Vista). More importantly, the total amount of MCP used during the 42-day production cycle was reduced from 34.3 kg to 13.0, 6.9 and 2.6 kg per MT of feed in 500, 1000, and 1500 FTU phytase treatments with full avP matrix application (Figure 1).
These savings are equivalent to 62%, 80%, and 92% reduction in MCP inclusion with dose of 500, 1000, and 1500 FTU phytase, respectively. With the current global market price of inorganic phosphorus, such a significant reduction will certainly translate to significant savings in diet cost.