| 摘要: |
| 【目的】研究饲粮消化能水平对陕北白绒山羊断奶公羔生长性能、营养物质表观消化率和血清生化指标的影响，确定饲粮适宜的能量水平。【方法】选取40只体质量（13.80±1.60） kg的3月龄陕北白绒山羊断奶公羔，随机分为4组，分别饲喂粗蛋白质含量均为118 g/kg、消化能分别为9.16（Ⅰ组）、9.66（Ⅱ组）、10.16（Ⅲ组）和10.66 MJ/kg（Ⅳ组）的4种饲粮，进行为期60 d的饲养试验，测算试验羊全期干物质采食量（DMI60）、平均日增重（ADG60）、料重比（F/G60）及每隔15 d的平均干物质采食量（DMI15）、平均日增重（ADG15），并测定血清生化指标。饲养试验结束后，每组选择3只羊进行消化代谢试验，预试期7 d，正试期4 d。【结果】①饲粮消化能水平对DMI60有极显著影响（P<0.01），对ADG60有显著影响（P<0.05），但对F/G60影响不显著（P>0.05）；各组试验羊DMI60和ADG60从高到低依次均为Ⅱ组>Ⅳ组>Ⅰ组>Ⅲ组，且Ⅱ组显著高于其他各组（P<0.05）。②各组试验羊的DMI15均随着饲养时间的增加而逐渐增大，且各组1~15，16~30，31~45和46~60 d的DMI15差异均达显著或极显著水平；各组试验羊ADG15均随着饲养时间的增加呈现出先增高后降低的变化趋势，其中31~45 d的ADG15最高。③Ⅱ组试验羊血清尿素氮含量最低，葡萄糖、白蛋白、总蛋白、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇含量最高；随着饲粮消化能水平的提高，试验羊血清游离脂肪酸、β-羟基丁酸和甘油三酯含量逐渐降低，总胆固醇含量逐渐升高。④Ⅱ组试验羊摄入总能和消化能显著高于Ⅰ组（P＜0.05），粪能极显著高于Ⅳ组（P＜0.01），Ⅱ、Ⅳ组试验羊总能表观消化率极显著高于Ⅰ组（P＜0.01）。⑤随着饲粮消化能水平的提高，干物质、有机物、粗蛋白质、中性洗涤纤维和酸性洗涤纤维的表观消化率呈现出先升高后降低的变化趋势，且均以Ⅱ组最高；粗脂肪表观消化率逐渐降低。【结论】陕北白绒山羊公羔断奶后45 d的饲粮最佳消化能水平为9.66 MJ/kg。 |
| 关键词: 陕北白绒山羊 断奶公羔 消化能 表观消化率 |
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| 基金项目:国家现代农业产业园建设绒山羊产业重点项目（2020HX02）；陕西省教育厅专项科研计划项目（20JK1017） |
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| Dietary digestive energy requirement of weaned male lambs of Shaanbei white cashmere goats |
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LI Longping,ZHANG Chen,LI Tuo,et al
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| Abstract: |
| 【Objective】This experiment investigated the effects of dietary energy level on growth performance,apparent digestibility of nutrients and serum biochemical indices of weaned male lambs of Shaanbei white cashmere goats and determined the optimal energy level.【Method】A total of 40 healthy 3-month-old weaned male Shaanbei white cashmere goats with similar body weight (approximate (13.80±1.60) kg) were selected and randomly divided into 4 groups (Ⅰ,Ⅱ,Ⅲ and Ⅳ) using a single factor randomized block design.The crude protein (CP) level was 118 g/kg,and groups Ⅰ,Ⅱ,Ⅲ and Ⅳ were fed four diets with different digestive energies (DE) of 9.16,9.66,10.16 and 10.66 MJ/kg,respectively.After 60 days,DMI60,ADG60,F/G60,DMI15,ADG15 and serum biochemical indexes were determined.In addition,3 goats per group were selected for a digestion and metabolism trial including pretrial for 7 days and trial for 4 days.【Result】① DE levels had significantly influence on DMI60 and ADG60 (P<0.05),but no significant influence on F/G60 (P>0.05).DMI60 and ADG60 were in the order of Ⅱ>Ⅳ>Ⅰ>Ⅲ with significant differences among group Ⅱ and other groups (P<0.05).② DMI15 of each group increased gradually with the increase of feeding days,and extremely significant differences were observed among periods of 1-15 d,16-30 d,31-45 d and 46-60 d (P<0.01).ADG15 increased first and then decreased with the increase of feeding days,and reached the highest at 31-45 d.③ Group Ⅱ had the lowest serum urinary nitrogen (BUN) content but the highest glucose (GLU),albumin (ALB),total protein (TP),high density lipoprotein cholesterol (HDL C) and low density lipoprotein cholesterol (LDL-C) contents.With the increase of dietary digestive energy level,serum contents of nonesterified fatty acid (NEFA),β-hydroxybutyric acid (β-HBA) and triglycerides (TG) gradually decreased,while content of total cholesterol (TCHO) gradually increased.④ The gross energy intake (GEI) and DE of group Ⅱ were significantly higher than those of group Ⅰ (P<0.05),fecal energy (FE) was extremely significantly higher than that of group Ⅳ (P<0.01),and the apparent energy digestibility of groups Ⅱ and Ⅳ was extremely significantly higher than that of group Ⅰ (P<0.01).⑤ Group Ⅱ had the greatest apparent digestibility of dry matter (DM),organic matter (OM),crude protein (CP),neutral detergent fiber (NDF) and acid detergent fiber (ADF),with a trend of first increasing and then decreasing.With the increase of dietary energy level,the apparent digestibility of ether extract (EE) gradually decreased.【Conclusion】The optimal dietary digestive energy level of male Shaanbei white cashmere goats at the time of 45 days after weaning was 9.66 MJ/kg. |
| Key words: Shaanbei white cashmere goats weaned male goats dietary digestive energy apparent digestibility |
