• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.229-240
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• 2003

An in vitro test and a broiler feeding trial were conducted to test the effect of hydrothermal treatment of wheat bran on phytate-P degradation and it’s feeding effect on performance of broilers. Hydrothermal treatment of wheat bran was carried out at 55$^{\circ}C$ with pH 5.5 buffer solution. Phytate-P content of wheat bran decreased quadrically as the wheat bran: buffer solution ratio increased from 1:0.5 to 1:5. Phytate-P degradation was not significantly affected by incubation times above 10 min., drying temperature (55$^{\circ}C$, 65$^{\circ}C$ and 75$^{\circ}C$) or pH of the buffer solution (5.5 and 7.0). A feeding trial was conducted with 240 sex separated d-old broiler chickens (Ross$^{\circledR}$). Broilers were randomly housed to 24 cages of 10 birds each. Six cages (3 of each sex) were assigned to 4 treatments: Control-normal level of non-phytate-P (NPP); LP-low NPP treatment which had 0.1% lower NPP than Control; LPWB-LP with wheat bran which provided 475 IU of plant phytase per kg diet; LPHWB-LP with hydrothermally treated wheat bran. Results of the feeding trial showed that broilers in the LP treatment gained significantly less than other treatments in starter period (1-21d) but only male broilers for growing LP gained significantly less than Control in the grower (22-35d) and overall period. There were no significant differences in weight gain among the birds of LPWB, LPHWB and Control. Feed intake during the overall period was not significantly different between LPWB and Control but that of LP was lower than LPHWB and that of LPHWB was lower than Control. Feed/gain ratio was significantly lower in LPHWB and LP than in Control and LPWP. Mortality was highest in LPHWB. Availability of crude fat, crude ash and Ca was significantly lower in LP than other treatments. Availability of P and Zn was higher in LPWB and LPHWB than in Control and LP. Availability of P, Mg and Zn was highest in LPHWP treatment. Excretion of P was significantly lower in low NPP treatments than in Control. Serum Ca level was highest whereas serum P level was lowest in LP. Tibial crude ash content was higher in wheat bran treatments, but lower in LP than Control. However, tibial Ca content was higher in Control and LP than wheat bran treatments. Tibial P content of LP and LPWB was lower than Control. However, tibial content of Fe was highest in LP. It was concluded that wheat bran, a source of plant phytase, could be used in low NPP broiler diets to prevent the depression of performance. Reduction of P excretion can be achieved concomitantly. Hydrothermal treatment of wheat bran was effective in improving utilizability of some minerals but was not effective in improving performance of broilers.