Fernandez S R, Zhang Y, Parsons C M
Department of Animal Sciences, University of Illinois, Urbana 61801.
Poult Sci. 1994 Oct;73(10):1563-71. doi: 10.3382/ps.0731563.
The effect of overheating on the nutritive value of cottonseed meal (CSM) for chicks and protein solubility in .2% KOH was evaluated. One-week-old male chicks were assigned to seven diets consisting primarily of corn and unautoclaved commercial CSM (expander-solvent extracted) or CSM that had been autoclaved for 20, 40, 60, 90, or 120 min at 121 C and 105 kPa. The protein level of the diets was either 21 or 22%, and FeSO4.7H2O was added to bind any free gossypol in the CSM. A control corn-soybean meal diet was included for comparison. A sample of full-fat cotton seeds extracted with a mixture of water-acetone-hexane without heating (DFCS) was also evaluated. The true digestibility of amino acids in cecectomized cockerels was determined for DFCS, three samples of unautoclaved commercial CSM, and the commercial CSM that had been autoclaved for 60 or 120 min. Growth performance of chicks was depressed (P < .05) by feeding CSM autoclaved for 40 to 60 min or more. Growth performance of chicks fed CSM diets was inferior (P < .05) to that obtained from the corn-soybean meal diet. Protein solubility for the unautoclaved commercial CSM was less than for DFCS (70 vs 60%) and did not decrease until 90 min of autoclaving. Average amino acid digestibility was higher for DFCS than in CSM (85 vs 74%). The mean true digestibilities of lysine, methionine, and cystine in the three unautoclaved commercial CSM were 64, 72, and 72%, respectively. Digestibilities of amino acids in CSM were reduced by 60 and 120 min of autoclaving.(ABSTRACT TRUNCATED AT 250 WORDS)
评估了过热对棉籽粕（CSM）对雏鸡营养价值及在0.2%氢氧化钾中蛋白质溶解度的影响。将1周龄雄性雏鸡分为7种日粮组，日粮主要由玉米和未高压灭菌的商业CSM（膨化-溶剂萃取）或在121℃和105 kPa下分别高压灭菌20、40、60、90或120分钟的CSM组成。日粮蛋白质水平为21%或22%，并添加硫酸亚铁·七水合物以结合CSM中任何游离棉酚。纳入对照玉米-豆粕日粮用于比较。还评估了用水-丙酮-己烷混合物未经加热提取的全脂棉籽样品（DFCS）。测定了DFCS、三个未高压灭菌的商业CSM样品以及高压灭菌60或120分钟的商业CSM在去盲肠公鸡中氨基酸的真消化率。饲喂高压灭菌40至60分钟或更长时间的CSM会使雏鸡生长性能下降（P<0.05）。饲喂CSM日粮的雏鸡生长性能低于（P<0.05）玉米-豆粕日粮。未高压灭菌的商业CSM的蛋白质溶解度低于DFCS（70%对60%），且直到高压灭菌90分钟才降低。DFCS的平均氨基酸消化率高于CSM（85%对74%）。三种未高压灭菌的商业CSM中赖氨酸、蛋氨酸和胱氨酸的平均真消化率分别为64%、72%和72%。高压灭菌60和120分钟会降低CSM中氨基酸的消化率。（摘要截短至250字）
