Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA.
J Anim Sci. 2011 May;89(5):1561-73. doi: 10.2527/jas.2010-2942.
The effects of dietary energy source and feed withdrawal on muscle glycolytic potential (GP) and blood acid-base responses to handling were investigated in slaughter-weight pigs (initial BW 94.7 ± 1.01 kg). Crossbred pigs (n = 96; 48 barrows, 48 gilts) were used in a randomized complete block design with a 4 × 2 × 2 factorial arrangement of treatments: l) diet [control, high fat (10% supplemental fat), low-digestible carbohydrate (20% total starch), and high-fat/low-digestible carbohydrate (10% supplemental fat and 20% total starch)]; 2) feed withdrawal (0 and 36 h); and 3) sex (barrow and gilt). Diets were fed for 28 d before the feed withdrawal treatment was applied, at the end of which all pigs were individually moved through a 12.20-m-long × 0.91-m-wide passageway for 16 laps (195 m total distance), with the assistance of an electric goad (2 times per lap). Longissimus muscle biopsies were collected at the beginning of the feeding and feed withdrawal periods and immediately after and 4 h after the handling procedure. Venous blood was collected 2 h before and immediately after the handling procedure to measure acid-base responses. At the end of the feeding period, pigs fed the control and high-fat diets were heavier (P < 0.001) than those on the low-digestible carbohydrate and the high-fat/low-digestible carbohydrate diets (129.8, 130.9, 114.0, and 122.1 kg, respectively; SEM 1.91). Diet, feed withdrawal, and sex did not affect (P > 0.05) blood acid-base responses to handling. Muscle GP at the end of the feeding period and 4 h posthandling was least (P < 0.05) for pigs fed the high-fat diet and similar for the other 3 diet treatments. Pigs subjected to 36 h compared with 0 h of feed withdrawal had less GP (P < 0.05) immediately after and 4 h after the handling procedure. There was an interaction between diet and feed withdrawal treatments for changes in GP from the start of feed withdrawal to 4 h posthandling. The reduction in GP was greater (P < 0.05) for fasted than for fed pigs receiving the control and high-fat diets, but was similar (P > 0.05) for fasted and fed pigs receiving the 2 low-digestible carbohydrate diets. In conclusion, neither dietary energy source nor fasting affected blood acid-base responses to handling; however, fasting-induced changes in LM GP were diet dependent.
研究了饲粮能值来源和停饲对屠宰体重猪（初始 BW 94.7±1.01kg）肌肉糖酵解潜能（GP）和血液酸碱反应的影响。采用交叉设计，将 96 头杂交猪（48 头公猪，48 头母猪）分为 4 个处理组，每组 24 头猪：1）饲粮[对照、高脂肪（10%添加脂肪）、低可消化碳水化合物（20%总淀粉）和高脂肪/低可消化碳水化合物（10%添加脂肪和 20%总淀粉）]；2）停饲（0 和 36h）；3）性别（公猪和母猪）。在应用停饲处理前，猪群先进行 28d 的饲粮饲养，停饲结束时，所有猪都在电棒的辅助下通过 12.20m 长×0.91m 宽的通道进行 16 圈（总距离 195m），每圈 2 次。在饲养和停饲期开始时以及处理后立即和 4h 时采集背最长肌活检样本。处理前 2h 和处理后立即采集静脉血样，以测定酸碱反应。在饲养期结束时，饲喂对照和高脂肪饲粮的猪比饲喂低可消化碳水化合物和高脂肪/低可消化碳水化合物饲粮的猪更重（P＜0.001）（129.8、130.9、114.0 和 122.1kg，SEM 1.91）。饲粮、停饲和性别对处理后血液酸碱反应无影响（P＞0.05）。在饲养期结束时和处理后 4h，饲喂高脂肪饲粮的猪 GP 最低（P＜0.05），而其他 3 种饲粮处理的 GP 相似。与 0h 停饲相比，36h 停饲的猪在处理后立即和 4h 时的 GP 减少（P＜0.05）。从停饲开始到处理后 4h，GP 变化与饲粮和停饲处理存在互作。在饲喂对照和高脂肪饲粮时，禁食猪的 GP 减少幅度大于采食猪（P＜0.05），但在饲喂低可消化碳水化合物饲粮时，禁食和采食猪的 GP 减少幅度相似（P＞0.05）。总之，饲粮能量来源或禁食均不影响猪对处理的血液酸碱反应；然而，禁食引起的 LM GP 变化取决于饲粮。
