Eight Chinese Yellow Cattle semitendinous muscles were irradiated using a 60Co irradiation source (with the dose of 1.13, 2.09, or 3.17 kGy) and stored (0 day or 10 days at 7 C) to estimate fatty acids change of neutral lipid (NL), polar lipid (PL) and total lipid (TL) fractions, and the beef quality change. Total saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) increased with irradiation, ratios of MUFA to SFA did not change in TL. Whilst, total polyunsaturated fatty acid (PUFA) reduced with irradiation, which resulted in PUFA to SFA ratio decreased in TL (0 day or 10 days). Purge loss and 2-thiobarbituric acid reactive substances values increased with irradiation (from 0 to 3.17 kGy) at 0 day, but these values were lower with irradiation at 10 days. Total bacterial counts decreased proportionally with irradiation dose increasing from 0 to 3.17 kGy. It can be concluded that fatty acid profiles in beef changed with irradiation; however, fatty acid profiles did not change much at 3.17 kGy compared with 1.13 or 2.09 kGy, and the beef quality were most acceptable at the dose of 3.17 kGy, thus, low dose of about 3 kGy gamma irradiation was recommended to apply in fresh beef preparation.

Seven hundred and three native and crossbred Chinese Yellow cattle (mean live weight: 523 38 kg) were slaughtered, chilled and segmented. The hot carcass weight (HCW, kg), fat thickness (FT, cm) and rib eye area (REA, cm2) were measured to predict weights and percentages of beef cattle retail cuts. A correlation analysis showed that the HCW and REA were positively correlated with the weights of the total retail cuts (TRC, kg), top grade retail cuts, prime retail cuts and percentage of total carcass weight. A regression analysis indicated that HCW and REA were the best predictors for the weight of total retail cuts (Y=-16.71+0.382 HCW+0.593 REA), and the HCW explained more of the variation than REA. Meanwhile, HCW and REA accounted for 62% of the variation of percentage of total retail cuts (Y=43.24-0.025 HCW+0.170 REA), whereas the REA was more valuable than the HCW. The FT contributed little in estimating weight or percentage of retail cuts.

取中国黄牛（公牛）的半腱肌（n=10）用来测定不同加工方式（蒸煮和微波加热）处理在不同中心温度水平（60、70、80℃）条件下脂肪酸组成的变化。结果显示，肌内脂肪中极性脂肪、中性脂肪及总脂中脂肪酸组成变化不一致。蒸煮时中性脂肪（NL）中多不饱和脂肪酸（PUFA）增加，而饱和脂肪酸（SFA）保持不变，P/S升高。而蒸煮时极性脂肪（PL）和总脂（TL）中PUFA含量减少，SFA含量升高，导致P/S下降。微波加热时NL、PL和TL中SFA显著增加，PUFA含量降低，但极性脂肪（PL）中PUFA含量降低不显著（p＞0.05），导致NL、PL和TL中P/S显著下降（p＜0.05）。M/S比值在两种加工条件下基本没变化。在蒸煮和微波加热条件下，n-6/n-3比值在中心温度达到80℃时比加热到60℃或70℃显著升高。结果提示，大理石花纹丰富的牛肉蒸煮烹饪对脂肪酸的保护效果好于微波加热；牛肉应尽量避免在过高温度（80℃）下处理，以减少营养成分的损失，利于人体健康。

通过在小麦基础日粮中添加木聚糖酶，研究了木聚糖酶对内仔鸡回肠及总消化道养分和非淀粉多糖（NsP）表观消化率及小肠形态的影响。试验将7日龄肉仔鸡随机分为3组，即为小麦基础日粮中添加0%、0.03%和0.1%的加酶组，饲喂至21日龄。结果表明：与对照组相比，0.1%的加酶组显著提高了淀粉在回肠和总消化道中的表观消化率（P<0.05），极显著提高了可溶性非淀粉多糖（sNsP）、不溶性非淀粉多糖（INsP）在回肠的表观消化率（P<0.01），显著提高了sNsP的总消化道表观消化率（P<0.05）。此外，O.1%的加酶组还极显著降低了十二指肠的肠壁厚（P<0.01），并极显著增加了肉仔鸡回肠隐窝深度和绒毛高度（P<0.01）。但0.1%的加酶组增加了空肠肠壁厚度（P<0.01），降低了空肠绒毛高度（P<0.05）和绒毛高度/隐窝深度比（JP<0.01）。试验结果表明小麦日粮中添加木聚糖酶可以提高肉仔鸡对养分的回肠和总消化道表观消化率并改善十二指肠和回肠形态。

通过在小麦基础日粮中添加国产酶（E）和进口酶（E）两种木聚糖酶制剂，研究了木聚糖酶对肉仔鸡各消化道食糜及粪中非淀粉多糖（NSP）消化率的影响。试验将7日龄肉仔鸡分成5组，分别为小麦对照组、小麦基础日粮中分别添加0.02%E