Performance and Phosphorus Utilization of Broiler Chickens Fed Low Phytate Barley and Pea Based Diets with Graded Levels of Inorganic Phosphorus

• Published in: Annals of animal science Vol. 17; no. 1; pp. 205 - 215
• Main Authors: Kahindi, Roseline Kafedha, Thacker, Philip A., Lee, Sang In, Kim, In Ho, Nyachoti, Charles Martin
• Format: Journal Article
• Language: English
• Published: Kraków De Gruyter Open 01.01.2017; De Gruyter Poland
• Subjects: bone mineralization; broilers; low phytate pea; phosphorus
• ISSN: 2300-8733; 1642-3402; 2300-8733
• DOI: 10.1515/aoas-2016-0023

The effects of feeding diets based on soybean meal, low phytate hulless barley (Lphybarley) and low phytate pea (Lphypea) with inorganic phosphorus (iP) reduced by 50 or 100% to broiler chickens on performance, P digestibility and bone characteristics were investigated. Two hundred and ten day-old (Ross 308 strain) broiler chicks (5 birds per cage; 6 cages per diet) were randomly allocated to 7 dietary treatments for a 21-day study. Diets were formulated based on soybean meal-normal phytate hulless barley (SBM-normbarley) with added inorganic P (iP) to meet NRC (1994) P requirements (SBM-normbarley100) or with 50% less iP (SBM-normbarley50), soybean meal-Lphybarley-Lphypea with added iP (Lphybarley-Lphypea100) or iP reduced by 50% (Lphybarley-Lphypea50) or 100% (Lphybarley-Lphypea0), and soybean meal-normbarleynormal phytate pea (normpea) with added iP (normbarley-normpea100) or iP reduced by 50% (normbarley-normpea50). Birds fed the Lphybarley-Lphypea0 diet had the lowest (P<0.001) ADG compared with those fed the other diets. Reducing iP by 50% led to a reduction (P<0.05) in ADG for birds fed the SBM-normbarley- and normbarley-normpea-based diets but not in the Lphybarley- Lphypea-based diet. Reducing iP by 50% led to a reduction (P<0.05) in ADFI in birds fed the SBM-normbarley-based diet and normbarley-normpea-based diet compared with those fed adequate iP. Feed conversion ratio was not affected by diet throughout the experimental period (P>0.10). Reducing iP content reduced P retention in the SBM-normbarley-based diet but not in the normbarley-normpea-based diet but tibia ash and length were reduced in birds fed both diets (P<0.05). Reducing dietary iP content linearly increased (P < 0.05) P retention and linearly decreased (P<0.05) tibia ash and length in the Lphypea-Lphybarley-based diets. In conclusion, feeding a low phytate hulless barley-low phytate pea based diet with iP reduced by 50% supported similar performance as control and increased P retention, suggesting that utilizing a combination of low phytate ingredients can reduce the need for supplemental iP with significant cost and environmental implication.