Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.8 (phytase)
 1,997 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Microbial phytase is a prominent feed enzyme used in animal feeds, but there is relatively little information on its use in laying hen diets. In this experiment, an Escherichia coli 6-phytase (Quantum) was evaluated for its efficacy in a 40-wk laying hen production trial. A total of 1,080 White Leghorn hens (540 each of Shaver and Bovan strains) were fed mash corn-soybean meal-based diets containing 0.35% (positive control, PC), 0.25% (negative control, NC1), or 0.15% (NC2) nonphytate phosphorus (NPP). Six more diets were manufactured by supplementing the negative control diets with 200, 400, and 600 U/kg of exogenous phytase, resulting in a total of 9 treatments. Each dietary treatment x strain subclass was replicated 4 times with 5 adjoining cages per replicate (3 hens per cage) in a randomized complete block design. Production performance was measured from 21 to 61 wk of age. Only minor differences in production characteristics were found between the PC and NC1 treatments regardless of phytase addition, indicating that 0.25% NPP resulted in P intake that was at or above the hen's requirement. In contrast, the hens fed 0.15% NPP diet without phytase supplementation had significantly (P < 0.05) reduced total hen housed egg production and body weight at 61 wk of age in comparison to the PC treatment, whereas the incidence of soft-shelled, cracked, and broken eggs was increased significantly (P < 0.05) in hens fed the NC2 diet. Addition of phytase to the NC2 diet improved these production characteristics to levels equal or better than the PC diet. The results indicated that Quantum phytase was efficacious in corn-soybean meal-based diets fed to White Leghorn laying hens and can be used to reduce diet supplementation with inorganic phosphorus.
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PMID:The efficacy of quantum phytase in a forty-week production trial using white leghorn laying hens fed corn-soybean meal-based diets. 1849 5

The efficacy of an Escherichia coli 6-phytase supplementation (Quantum) on nutrient digestibility-retention and bone ash in laying hens fed corn-soybean meal (CSM) diets was investigated. White Leghorn hens (Shaver and Bovan strains) were fed CSM diets containing 0.35% (positive control, PC), 0.25% (negative control 1, NC1), or 0.15% (negative control 2, NC2) nonphytate P from 21 to 61 wk of age. Six more diets were manufactured by supplementing the negative control diets with 200, 400, and 600 units per kilogram of exogenous phytase resulting in a total of 9 treatments. Each dietary treatment x strain subclass was replicated twice with 6 hens per replication. Fecal and ileal digesta samples were collected at 42 wk of age to determine apparent nutrient digestibility or retention. Left tibiae were collected at 42 and 61 wk of age to determine bone ash. The coefficients for ileal digestibility and fecal retention for protein were higher (P < 0.05) for the unsupplemented negative control treatments compared with the PC. A linear reduction in phytate digestibility and ileal protein digestibility was reported with increasing levels of phytase to the NC1 diet. Phytase addition to the NC1 treatment resulted in a linear decrease in the digestibility of amino acids except for methionine and proline. Significantly higher phytate digestibility was demonstrated with the NC2 treatment containing 400 units per kilogram of phytase compared with the PC. Tibial bone ash percentage was higher (P < 0.05) in 61-wk-old hens fed 200 or 400 units per kilogram of phytase-supplemented NC2 diets. Significantly higher diet AME and fecal protein retention were demonstrated for Shaver hens in comparison to the Bovan hens. Overall, the Quantum phytase was not efficacious at improving nutrient digestibility-retention in laying hens fed CSM diets deficient in nonphytate P.
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PMID:Effect of Quantum phytase on nutrient digestibility and bone ash in White Leghorn laying hens fed corn-soybean meal-based diets. 1943 30