Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, USA.
J Anim Sci. 2011 Mar;89(3):773-82. doi: 10.2527/jas.2010-3033.
A total of 120 pigs (60 barrows and 60 gilts; TR4 × PIC 1050; 54.4 kg initial BW) were used in an 83-d study to evaluate the effects of added fat in corn- and sorghum-based diets on growth performance, carcass characteristics, and carcass fat quality. Treatments were arranged in a 2 × 3 factorial with grain source (corn or sorghum) and added fat (0, 2.5, or 5% choice white grease; CWG) as factors. There were 2 pigs (1 barrow and 1 gilt) per pen and 10 replicate pens per treatment. Pigs and feeders were weighed on d 14, 22, 39, 53, 67, and 83 to calculate ADG, ADFI, and G:F. At the end of the trial, pigs were slaughtered and jowl fat and backfat samples were collected and analyzed for fatty acid profile. No interactions were observed for growth performance. Pigs fed sorghum-based diets had greater (P < 0.01) ADG than pigs fed corn-based diets. Adding CWG improved (linear, P < 0.01) ADG. Pigs fed corn-based diets tended to have greater (P < 0.09) carcass yield, 10th-rib backfat, and percentage lean than pigs fed sorghum-based diets. Adding CWG increased (linear, P = 0.02) 10th-rib backfat, tended to increase (linear, P = 0.08) HCW, and tended to decrease (linear, P = 0.07) percentage lean. There was no grain source × fat level interaction for iodine value (IV) in backfat, but an interaction (P = 0.03) was observed for IV in jowl fat. Adding CWG increased (P < 0.01) IV in jowl fat for pigs fed sorghum- and corn-based diets; however, the greatest increase was between 0 and 2.5% CWG in sorghum-based diets and between 2.5 and 5% CWG in corn-based diets. Pigs fed corn-based diets had less (P = 0.01) C18:1 cis-9 and MUFA but greater (P = 0.01) C18:2n-6, PUFA, and backfat IV than pigs fed sorghum-based diets. Increasing CWG in the diet increased (linear, P = 0.01) backfat IV. Of the 2 fat depots, backfat generally had a reduced IV than jowl fat. In summary, feeding sorghum-based diets reduced carcass fat IV and unsaturated fats compared with corn-based diets. As expected, adding CWG increased carcass fat IV regardless of the cereal grain in the diet.
总共使用了 120 头猪（60 头公猪和 60 头母猪；TR4 × PIC 1050；初始体重 54.4 公斤）进行了为期 83 天的研究，以评估玉米和高粱基日粮中添加脂肪对生长性能、胴体特性和胴体脂肪质量的影响。处理采用 2×3 因子设计，谷物源（玉米或高粱）和添加脂肪（0、2.5 或 5%选择白油脂；CWG）为因子。每个栏位有 2 头猪（1 头公猪和 1 头母猪），每个处理有 10 个重复栏位。在第 14、22、39、53、67 和 83 天，对猪和饲料进行称重，以计算 ADG、ADFI 和 G:F。试验结束时，屠宰猪并收集和分析颈肩肉脂肪和背脂样本来分析脂肪酸谱。生长性能没有观察到相互作用。饲喂高粱基日粮的猪的 ADG 高于饲喂玉米基日粮的猪（P<0.01）。添加 CWG 提高了 ADG（线性，P<0.01）。饲喂玉米基日粮的猪的胴体产肉率、第 10 肋骨背脂和瘦肉率均高于饲喂高粱基日粮的猪（P<0.09）。添加 CWG 增加了第 10 肋骨背脂（线性，P=0.02），增加了 HCW（线性，P=0.08），并降低了瘦肉率（线性，P=0.07）。背脂碘值（IV）没有观察到谷物源×脂肪水平的互作，但颈肩脂 IV 观察到互作（P=0.03）。添加 CWG 提高了饲喂高粱和玉米基日粮猪的颈肩脂 IV（P<0.01）；然而，在高粱基日粮中，从 0 到 2.5% CWG 和在玉米基日粮中，从 2.5%到 5% CWG 之间的增加最大。饲喂玉米基日粮的猪的 C18:1 顺-9 和 MUFA 较少（P=0.01），但 C18:2n-6、PUFA 和背脂 IV 较多（P=0.01）。日粮中添加 CWG 增加了背脂 IV（线性，P=0.01）。在这两个脂肪储存库中，背脂的 IV 通常低于颈肩脂。总之，饲喂高粱基日粮可降低胴体脂肪 IV 和不饱和脂肪，与玉米基日粮相比。正如预期的那样，无论日粮中的谷物如何，添加 CWG 都会增加体脂 IV。
