The effect of non-phytate phosphorus and phytase levels on performance, egg and tibia quality, and pH of the digestive tract in hens fed higher-calcium-content diet

Abstract

THe effect of three levels of non-phytate phosphorus (NPP) (3.0, 2.1, and 1.7 g/kg) and two levels of 3-phytase (F) (0 and 150 phytase units (FTU)/kg) together with a high dietary calcium concentration (approximately 41.0 g/kg) on the performance characteristics, egg quality, pH of the digestive tract, and tibia bone quality of ISA Brown hens housed in enriched cages was evaluated. THe diets with 3.0 g/kg of NPP with and without F and 2.1 g/kg of NPP with 150 FTU of F significantly increased egg production (P = 0.022) and daily egg mass production (P = 0.030). A low level of NPP decreased (P < 0.001) the body weight of hens at the end of the experiment. THe highest values of albumen height (P < 0.001), albumen index (P = 0.004), Haugh units (P = 0.001), and albumen percentage (P = 0.004) were associated with the diet with the low level of dietary NPP without F addition. THe low level of NPP with 3-phytase increased the calcium and phosphorus contents in eggshells (P = 0.002 and P = 0.050). THe lowest values of dry matter (P < 0.001) and ash content in tibia bone (P = 0.040) were measured for the hens fed the diet with 3.0 g/kg of NPP and 3-phytase supplementation. In addition, the low level of phosphorus without F addition increased (P = 0.031) the pH value in the small intestine to 6.21. In conclusion, 2.1 g of NPP with 150 FTU was found to be sufficient in the diet of hens in the middle of the laying cycle housed in enriched cages. But with respect to egg quality, higher calcium content decreased positive effect of F addition in diets with different levels of phosphorus.

Effect of dietary magnesium, calcium, phosphorus, and limestone grain size on productive performance and eggshell quality of hens

“…When the Ca : NPP ratio was narrow, such as in Experiment 1 and in the study by Kim et al (2013), the dietary Mg did not influence the laying intensity, but it increased the eggshell strength. A wide Ca : NPP ratio of 19.5 : 1 and 24 : 1 without Mg supplementation significantly reduced laying intensity in the experiment of Englmaierova et al (2014). A similar relationship was seen in Experiment 2.…”

Negative effect of phytase superdosing in laying hens

“…The Scientific Panel on additives and products or substances used in animal feed (FEEDAP Panel), which belongs to the EFSA, concluded that the additive has the potential to be effective in laying hens at a dose of 150 FTU/kg feed. This conclusion was confirmed by Englmaierova et al (2014), who reported that using dietary contents 2.1 g/kg NPP and 41 g/kg Ca with the addition of 150 FTU/ kg 3-phytase Natuphos ® resulted in higher egg production and higher Ca and P concentrations in egg shells compared to the positive control (3 g/kg NPP). Olukosi et al (2013) determined that a high dose of Ph in the diet releases more Ca from phytate and that this greater release is reflected in a higher concentration of Ca in bones.…”

Effects of a low-phosphorus diet and exogenous phytase on performance, egg quality, and bacterial colonisation and digestibility of minerals in the digestive tract of laying hens

“…Based on previous findings that high doses of NPP had a negative effect on hen performance (Skrivan et al 2010;Englmaierova et al 2012Englmaierova et al , 2014a, low levels of NPP were chosen for this study. An increase in the NPP level from 1.8 to 2.1 g/kg significantly decreased egg production, egg weight, and egg mass production and significantly increased the feed intake per hen, the feed intake per egg, and the feed conversion ratio.…”