Mialon M M, Renand G, Ortigues-Marty I, Bauchart D, Hocquette J F, Mounier L, Noël T, Micol D, Doreau M
INRA, UMR1213 Herbivores, F-63122 Saint-Genès-Champanelle, France Clermont Université, VetAgro Sup, UMR1213 Herbivores, BP 10448, F-63000, Clermont-Ferrand, France
INRA, UMR1313 GABI, F-78352 Jouy-en-Josas, France.
J Anim Sci. 2015 Jan;93(1):319-33. doi: 10.2527/jas.2014-7845. Epub 2014 Nov 20.
The aim of this study was to compare the responses in fattening performance and meat composition for high-concentrate diets rich in either starch and lipids (especially omega-3 fatty acids) or fibrous by-products. A total of 140 Charolais bulls (initially 319 ± 27 kg BW) were allocated to 3 high-concentrate diets and were fattened for up to 18 mo. The diet treatments included concentrate mixtures rich in either fiber (FR; n = 56) or starch plus linseed (diets SL and SLR; n = 56 and n = 28, respectively) and barley straw. The concentrate mix was offered ad libitum in SL and FR diets but was kept isoenergetic to the FR diet in the SLR diet. Bulls were weighed every 15 d. Feed intake was measured daily. Carcass composition was assessed for all animals slaughtered at 699 ± 65 kg BW. Meat nutritional quality traits (e.g., fat content and fatty acid composition focusing on n-6 and n-3 polyunsaturated fatty acids) were measured on the longissimus thoracis, rectus abdominis, and semitendinosus muscles. Metabolic enzyme activity (phosphofructokinase, lactate dehydrogenase, and cytochrome-c oxidase) was measured on these muscles and on liver. The SL diet bulls had greater fattening performance, BW gain (P = 0.006), and efficiency for growth (P = 0.025) at an energy intake similar to that of FR diet bulls. They also had heavier carcasses with a greater proportion of fat. However, liver samples showed no difference in specific metabolic activity. Compared to bulls fed the SL diet, bulls fed SLR consumed 15% less energy and had lower BW gain (P < 0.001) but were slightly more efficient for growth (P = 0.010). They had lower carcass weight but a greater muscle-to-fat ratio. Compared to bulls fed the FR diet, SLR bulls had lower than planned NEg intake and lower BW gain but did not have differences in body composition. Compared to the FR diet, the SL diet led to a greater omega-3 fatty acid content because of a greater supply of dietary linoleic acid, especially in lean muscle.
本研究的目的是比较富含淀粉和脂质（特别是ω-3脂肪酸）的高浓缩日粮或纤维副产品对育肥性能和肉成分的影响。总共140头夏洛莱公牛（初始体重319±27千克）被分配到3种高浓缩日粮中，并育肥长达18个月。日粮处理包括富含纤维的浓缩混合物（FR；n = 56）或淀粉加亚麻籽的混合物（日粮SL和SLR；分别为n = 56和n = 28）以及大麦秸秆。在SL和FR日粮中，浓缩混合物可自由采食，但在SLR日粮中，其能量水平与FR日粮保持等能。每15天对公牛进行称重。每天测量采食量。对所有体重达到699±65千克时屠宰的动物进行胴体组成评估。在胸最长肌、腹直肌和半腱肌上测量肉的营养品质性状（如脂肪含量和以n-6和n-3多不饱和脂肪酸为重点的脂肪酸组成）。在这些肌肉和肝脏上测量代谢酶活性（磷酸果糖激酶、乳酸脱氢酶和细胞色素c氧化酶）。在能量摄入量与FR日粮公牛相似的情况下，SL日粮公牛具有更好的育肥性能、体重增加（P = 0.006）和生长效率（P = 0.025）。它们的胴体也更重，脂肪比例更高。然而，肝脏样本的特定代谢活性没有差异。与饲喂SL日粮的公牛相比，饲喂SLR的公牛能量消耗减少15%，体重增加较低（P < 0.001），但生长效率略高（P = 0.010）。它们的胴体重较低，但肌肉与脂肪比例较高。与饲喂FR日粮的公牛相比，SLR公牛的净能量摄入量低于计划水平，体重增加较低，但身体组成没有差异。与FR日粮相比，SL日粮由于日粮中亚油酸供应增加，导致ω-3脂肪酸含量更高，尤其是在瘦肉中。
