Wang X, Parsons C M
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
Poult Sci. 1998 Jul;77(7):1010-5. doi: 10.1093/ps/77.7.1010.
The digestibility and bioavailability of amino acids (AA) in meat and bone meals (MBM) may vary greatly due to different processing conditions. In the present study, two experiments were conducted to evaluate formulation of diets containing high or low quality MBM on a total AA basis vs a digestible or bioavailable AA basis compared to a corn-soybean meal control diet. Lysine, methionine, and cystine digestibilities (precision-fed cecectomized rooster assay) were 92, 91, and 71%, respectively, for high quality MBM and were 71, 83, and 31%, respectively, for the low quality MBM. Bioavailability values (slope-ratio chick growth assay) for TSAA in the two MBM were approximately 15 percentage units lower than the digestibility values. Male crossbred chicks were fed a 20% CP corn-SBM diet or corn-SBM diets containing 10 or 20% high or low quality MBM that were formulated to be equal in total, digestible, or bioavailable AA to the corn-SBM diet. All diets contained 3,200 kcal of TMEn/kg, 1.4% Ca, and 0.7% nonphytate P and were fed to chicks from 8 to 22 d posthatching. Growth performance of chicks fed 10 or 20% high or low quality MBM on a total AA basis was lower (P < 0.05) than that of chicks fed the corn-SBM diet. Growth of chicks fed 10% low quality MBM or 10 or 20% high quality MBM on a digestible or bioavailable basis was equivalent to that of chicks fed the corn-SBM diet; however, dietary inclusion of 20% low quality MBM depressed growth (P < 0.05) even on a digestible or bioavailable AA basis. Further supplementation of the latter diet with additional AA yielded growth that was similar to the corn-SBM control diet. The results indicated that formulation of diets containing MBM on a digestible or bioavailable AA basis is superior to formulation on a total AA basis. However, feeding high levels of a low quality MBM may require additional AA supplementation to obtain maximum chick growth.
由于加工条件不同，肉骨粉（MBM）中氨基酸（AA）的消化率和生物利用率可能有很大差异。在本研究中，进行了两项试验，以评估与玉米 - 豆粕对照日粮相比，基于总氨基酸、可消化氨基酸或生物可利用氨基酸配制的含高质量或低质量肉骨粉日粮。对于高质量肉骨粉，赖氨酸、蛋氨酸和胱氨酸的消化率（精确饲喂去盲肠公鸡试验）分别为92%、91%和71%，而低质量肉骨粉的相应消化率分别为71%、83%和31%。两种肉骨粉中总含硫氨基酸（TSAA）的生物利用率值（斜率比雏鸡生长试验）比消化率值低约15个百分点。给雄性杂交雏鸡饲喂含20%粗蛋白的玉米 - 豆粕日粮，或含10%或20%高质量或低质量肉骨粉的玉米 - 豆粕日粮，这些日粮在总氨基酸、可消化氨基酸或生物可利用氨基酸含量上与玉米 - 豆粕日粮相等。所有日粮每千克含3200千卡真代谢能、1.4%钙和0.7%非植酸磷，并在雏鸡出壳后8至22天饲喂。以总氨基酸为基础饲喂10%或20%高质量或低质量肉骨粉的雏鸡生长性能低于（P < 0.05）饲喂玉米 - 豆粕日粮的雏鸡。以可消化或生物可利用氨基酸为基础饲喂10%低质量肉骨粉或10%或20%高质量肉骨粉的雏鸡生长情况与饲喂玉米 - 豆粕日粮的雏鸡相当；然而，日粮中添加20%低质量肉骨粉即使在可消化或生物可利用氨基酸基础上也会抑制生长（P < 0.05）。给后一种日粮进一步补充额外的氨基酸后，生长情况与玉米 - 豆粕对照日粮相似。结果表明，基于可消化或生物可利用氨基酸配制含肉骨粉的日粮优于基于总氨基酸配制。然而，饲喂高水平的低质量肉骨粉可能需要额外补充氨基酸以实现雏鸡最大生长。
