Wang Xuan, Du Baolong, Nian Fang, Ru Yingjun, Sun Likun, Qin Shizhen, Tang Defu
College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China.
Diasham Resources Pte. Ltd., Singapore 629314, Singapore.
Animals (Basel). 2023 Apr 17;13(8):1373. doi: 10.3390/ani13081373.
As an important food crop, cassava is rich in nutrients and high in starch content and is widely used in the production of industrial raw materials. However, the utilization value of cassava is limited due to the reduction of planting area and the existence of anti-nutritional factors. Therefore, we evaluated in vitro cassava starch digestibility and in vivo growth performance of broilers in a 3 × 3 factorial arrangement of treatments using three processing methods (mechanical crushing (MC), steam conditioning (SC), and puffing conditioning (PU)) and three conditioning temperatures (60, 75, and 90 °C) to screen for the optimal processing method and conditioning temperature to improve the utilization of cassava. In the in vitro cassava starch digestion study, the digestibility and digestion rate ( < 0.01) were higher at conditioned 90 °C than that at 60 or 75 °C, and PU was higher than SC and MC ( < 0.01) (0.25-2 h). The amylose content and amylose/amylopectin at conditioned 60 °C or PU were lower ( < 0.01) than that of 75 or 90 °C or SC, whereas the opposite was true for amylopectin content ( < 0.01). The resistant starch content of SC or PU was lower ( < 0.01) than MC. In the in vivo study, broilers fed diets conditioned at 60 °C or SC had a lower ( < 0.05) feed-to-gain ratio than those fed diets conditioned at 90 °C or PU diets. The ileum apparent digestibility of starch and AME were higher ( < 0.05) for broilers fed SC diets than for those fed MC diets. These results indicate that cassava starch promoted starch digestion rate by reducing amylose content and amylose/amylose under PU combined with a conditioning temperature of 60 °C, ileum digestibility of starch in broilers fed SC diets was higher than MC diets regardless of conditioning temperature, and SC diets increased AME and decreased F/G to promote growth performance of broilers.
木薯作为一种重要的粮食作物，营养丰富，淀粉含量高，广泛应用于工业原料生产。然而，由于种植面积减少和抗营养因子的存在，木薯的利用价值受到限制。因此，我们采用三种加工方法（机械粉碎（MC）、蒸汽调质（SC）和膨化调质（PU））和三种调质温度（60、75和90℃），以3×3析因试验设计评估了木薯淀粉的体外消化率和肉鸡的体内生长性能，以筛选提高木薯利用率的最佳加工方法和调质温度。在体外木薯淀粉消化研究中，90℃调质处理的木薯淀粉消化率和消化速率（P<0.01）高于60℃或75℃处理，且PU处理高于SC和MC处理（P<0.01）（0.25 - 2小时）。60℃调质或PU处理的直链淀粉含量和直链淀粉/支链淀粉比值低于75℃或90℃处理或SC处理（P<0.01），而支链淀粉含量则相反（P<0.01）。SC或PU处理的抗性淀粉含量低于MC处理（P<0.01）。在体内研究中，饲喂60℃调质或SC处理日粮的肉鸡料重比低于饲喂90℃调质或PU处理日粮的肉鸡（P<0.05）。饲喂SC处理日粮的肉鸡回肠淀粉表观消化率和AME高于饲喂MC处理日粮的肉鸡（P<0.05）。这些结果表明，在PU结合60℃调质温度下，木薯淀粉通过降低直链淀粉含量和直链淀粉/支链淀粉比值提高了淀粉消化速率；无论调质温度如何，饲喂SC处理日粮的肉鸡回肠淀粉消化率均高于饲喂MC处理日粮的肉鸡；SC处理日粮提高了AME并降低了F/G，促进了肉鸡的生长性能。
