Assessment of a bacterial 6-phytase in the diets of broiler chickens.

Abstract

Two 21-d broiler experiments were conducted to assess the efficacy of a bacterial 6-phytase expressed in Aspergillus oryzae on growth performance, nutrient utilization, and intestinal molecular markers. Two hundred forty birds in 5 treatments (experiment 1) or 256 birds in 4 treatments (experiment 2) were used. The treatments included a negative control diet that was marginally deficient in P (NC) or NC plus tricalcium phosphate, 500, 1,000, or 2,000 phytase units/kg (experiment 1), and NC or NC plus monocalcium phosphate, 500 or 1,000 phytase units/kg (experiment 2). In both experiments, excreta were collected on d 19 to 21, whereas birds and feed were weighed and ileal digesta collected on d 21. For experiment 1, mucosa scraping was collected from the duodenum, jejunum, and ileum from all birds for quantification of expression level of gut level inflammatory cytokines, Toll-like receptors, and phosphate transporter (NaPi-IIb). In both experiments, tricalcium phosphate, monocalcium phosphate, and phytase supplementation improved (P < 0.05) weight gain and percentage tibia ash. Phosphorus and Ca retention and phytic acid disappearance improved (P < 0.05) with phytase supplementation (experiment 1) and there was an increase (P < 0.01) in Ca and P retention in response to phytase supplementation (experiment 2). Diets did not affect the expression of gut level cytokines, Toll-like receptors, or the mucin gene. Phytase supplementation tended to decrease (P < 0.10) the expression of NaPi-IIb. It was concluded from these studies that the bacterial 6-phytase was effective in enhancing growth of broilers receiving low-P diets as well as in increasing efficiency of P utilization and phytic acid degradation.

• Authors: O A Olukosi, C Kong, F Fru-Nji, K M Ajuwon, O Adeola
• Journal: Poultry science (Poult Sci) Vol. 92 Issue 8 Pg. 2101-8 (Aug 2013) ISSN: 0032-5791 [Print] England
• PMID: 23873558 (Publication Type: Journal Article, Randomized Controlled Trial)

Chemical References

• Mucin-2
• Sodium-Phosphate Cotransporter Proteins, Type I
• 6-Phytase
• Calcium

Topics

• 6-Phytase (metabolism, pharmacology)
• Animal Feed (analysis)
• Animal Nutritional Physiological Phenomena
• Animals
• Aspergillus oryzae (metabolism)
• Calcium (metabolism)
• Chickens (growth & development)
• Diet (veterinary)
• Gene Expression Regulation
• Intestinal Mucosa (metabolism)
• Male
• Mucin-2 (genetics, metabolism)
• Real-Time Polymerase Chain Reaction
• Sodium-Phosphate Cotransporter Proteins, Type I (genetics, metabolism)