ABSTRACT

The aim of the present study was to investigate the effects of substituting dietary barley grain by different sources and levels of fat on performance and meat quality of Holstein young bulls. Twenty-eight Holstein male calves, 274 ± 32 kg initial body weight, were used in a completely randomised design with a 2 × 2 factorial treatment arrangement for 100 d (with 10 d of adaptation). Seven animals were randomly allocated per treatment. Four dietary treatments were tested, which included: (1) diet supplemented with saturated fat (Energizer® RP10) at low level (diet with high barley and starch content), (2) diet supplemented with saturated fat at high level (diet with low barley and starch content), (3) diet supplemented with unsaturated fat (Persiafat) at low level (diet with high barley and starch content) and (4) diet supplemented with unsaturated fat at high level (diet with low barley and starch content). The dry matter intake, average daily gain, feed conversion ratio and carcass traits were not affected by supplemental fat sources and levels. Total tract digestibility of acid detergent fibre was improved after inclusion of both rumen-protected fat sources while other nutrient digestibilities were not affected by the fat sources or levels. In conclusion, partial replacing of dietary starch with fat supplements has not negative effects on calves’ performance and digestibility of neutral detergent fibre.

摘要

本研究的目的是研究用不同来源和脂肪水平替代日粮大麦谷物对荷斯坦幼公牛的生产性能和肉质的影响。28 头荷斯坦公牛犊，初始体重 274 ± 32 kg，用于完全随机设计，采用 2 × 2 因子处理安排 100 天（适应 10 天）。每次治疗随机分配七只动物。测试了四种饮食治疗，包括：（1）低水平补充饱和脂肪（Energizer® RP10）的饮食（大麦和淀粉含量高的饮食），（2）高水平补充饱和脂肪的饮食（低水平的饮食）大麦和淀粉含量），(3) 低水平补充不饱和脂肪(Persiafat) 的饮食(大麦和淀粉含量高的饮食) 和(4) 高水平补充不饱和脂肪的饮食(大麦和淀粉含量低的饮食)。干物质摄入量、平均日增重、饲料转化率和胴体性状不受补充脂肪来源和水平的影响。加入两种瘤胃保护脂肪源后，酸性洗涤纤维的总消化道消化率得到改善，而其他营养物质的消化率不受脂肪来源或水平的影响。总之，用脂肪补充剂部分替代日粮淀粉对小牛的生产性能和中性洗涤纤维的消化率没有负面影响。饲料转化率和胴体性状不受补充脂肪来源和水平的影响。加入两种瘤胃保护脂肪源后，酸性洗涤纤维的总消化道消化率得到改善，而其他营养物质的消化率不受脂肪来源或水平的影响。总之，用脂肪补充剂部分替代日粮淀粉对小牛的生产性能和中性洗涤纤维的消化率没有负面影响。饲料转化率和胴体性状不受补充脂肪来源和水平的影响。加入两种瘤胃保护脂肪源后，酸性洗涤纤维的总消化道消化率得到改善，而其他营养物质的消化率不受脂肪来源或水平的影响。总之，用脂肪补充剂部分替代日粮淀粉对小牛的生产性能和中性洗涤纤维的消化率没有负面影响。