【摘要】 【目的】通过探索生长期肉用绵羊的甲烷（CH₄）排放规律,旨在建立相关的CH₄预测模型。【方法】采用单因素试验设计,以饲粮NFC/NDF（非纤维性碳水化合物/中性洗涤纤维）为0.78自由采食组的平均日增重作为饲粮NFC/NDF为1.03组和2.17组的限饲标准,在此基础下测定肉用绵羊的生长性能、营养物质消化率和甲烷产量,并分析肉用绵羊不同体重阶段的甲烷产量与饲粮干物质基础下的营养物质含量、营养物质摄入量、可消化营养物质摄入量及营养物质消化率间的回归关系。【结果】预测肉用绵羊生长早期（25—35 kg）CH₄产量的最佳一元和多元回归模型分别为:CH₄(L·d^-1)=-26.58×NFC/NDF+92.7（R²=0.772,P <0.001）;CH₄ (L·d^-1)=2.71×NDFD-2.45×DMD-0.97 CPD+124.46（R²=0.846,P=0.001）。预测肉用绵羊生长后期（48-55 kg）CH₄产量的最佳一元和多元回归模型分别为:CH₄ （L/d）=-57.00×GE (MJ·kg^-1)+1076.0（R²=0.581,P=0.002）;CH₄/BW^0.75 （L/kg0.75）=-0.013×NDF intake （g/d）-0.13×CP intake （g/d）+0.02×DM intake （g/d）+0.84（R²=0.652,P=0.019）。而肉用绵羊生长期整体CH₄产量的最佳一元和多元预测模型分别为:CH₄（L/d）=-26.94×NFC/NDF+90.71（R²=0.655,P <0.001）;CH₄/BW^0.75 （L/kg0.75）=0.005×Digestible NDF intake (g·d^-1)+0.011×Digestible DM intake (g·d^-1)-0.097×Digestible CP intake (g·d^-1)-4.78 （R²=0.722,P <0.001）。【结论】建立了肉用绵羊独立生长阶段（25—35 kg、48—55 kg）和整体生长阶段（25—55 kg）的CH₄预测模型。研究表明,处于不同体重阶段的肉用绵羊的最佳甲烷预测因子不尽相同,且甲烷产量受饲粮NFC/NDF影响较大。这可为今后评估我国饲养模式下的甲烷产量提供理论依据,也可为肉用绵羊饲粮的合理配制提供技术参考。更多还原

【Abstract】 【Objective】 This study was aimed to investigate the methane（CH₄） emission and develop CH₄ prediction models of growing sheep. 【Method】 The average daily weight gain of the treatment of NFC/NDF = 0.78, 1.03 and 2.17 was used as the reference for the restricting level of feed for the other three treatments, respectively, and the digestibility of nutrients and methane production of meat sheep were measured on this basis. Furthermore, the regression relationships were established between CH₄ production and dietary nutrient content, nutrient intake, digestible nutrients intake, and apparent digestibility of nutrients. 【Result】When the sheep grew from 25 to 35 kg BW, the most accurate single-variable and multivariate regression model were shown below:CH₄（L/d）=-26.58 × NFC/NDF + 92.70（R² = 0.772, P <0.001）; CH₄（L/d） = 2.71 × NDFD-2.45 × DMD-0.97 × CPD + 124.46（R² = 0.846, P = 0.001）. When the sheep grew from 48 to 55 kg BW, the most accurate single-variable and multivariate regression model were shown below: CH₄（L/d） =-57.00 × GE(MJ·kg^-1) + 1076.01（R² = 0.581, P = 0.002）; CH₄/BW^0.75(L·kg^-1) =-0.01 ×NDFI(g·d^-1)-0.13 × CPI(g·d^-1) + 0.02 × DMI(g·d^-1) + 0.84（R² = 0.652, P = 0.019）. The most accurate single-variable and multivariate regression model in the overall growing period of sheep were shown below: CH₄（L/d）=-26.94 × NFC/NDF + 90.71（R² = 0.655, P <0.001）; CH₄/BW^0.75(L·kg^-1) = 0.005 × DNDFI(g·d^-1) + 0.011 × DDMI(g·d^-1)-0.097 × DCPI(g·d^-1)-4.78（R² =0.722, P <0.001）. 【Conclusion】 The regression relationships were established for the respective growth periods（25-35 kg and48-55 kg BW） and the overall growth period（25-55 kg BW）. The studies showed that the optimal methane prediction factors for meat sheep at different weight were various, and methane production was greatly affected by dietary NFC/NDF, which could be used as a theoretical basis for the evaluation of methane production under the breeding model in China and a reference for the diets of meat sheep.更多还原