臺灣博碩士論文加值系統

反芻動物瘤胃經醱酵生成之甲烷，為影響氣候變遷之溫室氣體之一，佔總能攝取量之5~10%。目前降低反芻動物甲烷排放之兩大策略為提升動物生產效率及調整飼糧組成分，例如，改善飼糧中芻料種類、品質及加工方式等。本研究目的為餵飼國內常用芻料對臺灣之荷蘭牛生長性狀、營養分利用率及甲烷排放量之影響。試驗一，建立兩座獨立簡易開放式呼吸室，每室長寬高為550 × 228 × 211 cm3（體積27.7 m3），每室每次置入一頭牛以測定其甲烷排放量，於呼吸室兩側設有2個進氣口（ϕ 30 cm）及1個出氣口（ϕ 30 cm），並在室內靠近出氣口側裝置排風管，藉由排風機抽氣以導引氣體流動，出風口氣體平均流速為15.3 m3/分。試驗用3種芻料為百慕達乾草、燕麥乾草及玉米青貯料，分別佔總飼糧50%，並佐以精料50%。試驗二，依逢機完全區集設計（Randomized Complete Block Design，RCBD）。選用3頭平均體重為526 ± 69公斤，日產乳量為16.3 ± 4.4公斤之初產泌乳牛，依據試驗設計將每頭牛視為一區集，將之依每3週為一期分為3個期別，每一期別視為一個試驗單位，將3種芻料飼糧處理組逢機分配於每頭牛之3個試驗期中。試驗三、選用2頭生長女牛及1頭乾乳牛，將3種芻料飼糧處理組依3 × 3拉丁方格設計（Latin Square Design）分配於該3頭試驗牛。每一試驗期包含14天適應期與7天收集期。於收集期收集飼料、糞便、尿液及瘤胃液等樣品，且以簡易開放式呼吸室測定牛隻甲烷排放量。結果顯示，芻料種類對泌乳牛之生長性狀、乳產量、乳脂校正乳（3.5% FCM）、體內氮及能量平衡、瘤胃pH值與瘤胃液中揮發性脂肪酸濃度等皆無顯著影響，餵飼玉米青貯料之泌乳牛其乾物質、有機質、中洗纖維及半纖維素消化率顯著較低；餵飼燕麥乾草之泌乳牛有顯著較低之甲烷生成量（g/d and kg/yaer）及甲烷能量轉換係數（% of GEI）。芻料種類對非泌乳牛之生長性狀、營養分消耗量、營養分消化率、體內氮及能量平衡與甲烷生成總量等皆無顯著影響。餵飼燕麥乾草之非泌乳牛以甲烷形式釋出之能量顯著較低。綜合上述結果，在不影響生長及泌乳性狀之前提下，為降低荷蘭牛之甲烷生成量，以餵飼燕麥乾草為芻料來源之飼糧應是較適當之選擇。

Emission of methane is a major concern for ruminant production because of its adverse consequences to climate change. Improved animal productivity and dietary manipulation are two strategies that have shown potential for reducing methane emissions. Factors such as the forage species and quality and processing of forage may influence CH4 production in the rumen. The purpose of this study was to determine methane production as well as growth performance and nutrient utilization of Holstein cows fed with different forages in Taiwan. In experiment 1, two identical brief open-circuit chambers, each with dimension of 5.5 m width × 2.3 m depth × 2.1 m height (volume=27.7 m3), were established. The chambers were equipped with two air inlets (ϕ 30 cm) and an outlet (ϕ 30 cm) with an averaging air flow rate 15.3 m3/min forced by an electric fan. Inlet and outlet gases were sampled every 0.5 hour for CH4 concentration analysis when the cows stayed individually in the chamber. In experiment 2 and 3, three forages, i.e., bermuda hay (BH), oat hay (OH) and corn silage (CS) along with 50% concentrate on DM basis were used as dietary treatments. In experiment 2, three Holstein cows (BW = 526 ± 69 kg, DIM = 238 ± 143 days) were used and each was regarded as a block that was divided into three 3-week periods, each with 14 d for adaptation and 7 d for collecting samples regarded as an experimental unit. According to a randomized complete block design (RCBD), the treatments were randomly allotted into three periods in a cow. Experiment 3 was conducted with three Holsteins non-lactating cows (BW = 452 ± 141 kg) according to a 3 × 3 Latin square design, in which each interval lasting for 21 d including 14 d for adaptation and 7 d for measurements and sample collection. The samples including feces, urine, and rumen fluid were collected and CH4 emission from the cow was determined at each period. The results showed that growth performance, milk production, 3.5% FCM as well as pH value and VFA concentration in the rumen of lactating cows were not significantly different among the forage treatments. CH4 emissions (g/d and kg/year) and CH4 conversion rate (% of gross energy intake) were significant lower by feeding the lactating cows with OH diet. Intake, apparent digestibilities of nutrients as well as retention of nitrogen and energy in the non-lactating cows were not significantly different among the forage treatments. Comparing with the other forages, feeding OH diet to non-lactating cows resulted in the lowest CH4 production and CH4 conversion rate. In conclusion, when decreasing CH4 emission is concerned, oat hay is a proper choice for feeding Holstein cows in Taiwan.

目 錄

壹、中文摘要 1
貳、英文摘要 3
参、前言 5
肆、文獻探討 6
一、 溫室氣體（greenhouse gas）與氣候變遷（climate change） 6
二、 國內反芻動物瘤胃甲烷排放與減量研究之現況 9
三、 反芻動物之瘤胃生理 12
(一) 瘤胃中微生物的醱酵作用 12
(二) 碳水化合物在瘤胃中的消化 12
(三) 氨態氮（NH3-N）之生成 13
(四) 揮發性脂肪酸（VFA）之生成 15
(五) 甲烷生成（methanogenesis） 17
四、 影響反芻動物甲烷排放之因子 20
(一) 採食量 20
(二) 飼糧芻精比 20
(三) 芻料的種類及加工 20
(四) 瘤胃pH值 22
(五) 飼養方法及環境溫度 23
(六) 瘤胃中原蟲 23
(七) 添加劑 24
1.氫離子劑 24
2.脂肪 24
3.植物萃取物 24
4.有機酸 25
伍、試驗材料與方法 26
一、 試驗I 簡易開放式呼吸室之建立及甲烷排放量測定之標準化 26
(一) 簡易開放式呼吸室之設計與建立 26
(二) 甲烷測定條件及檢量線之建立 29
1.測定條件 29
2.甲烷濃度檢量線之建立 29
(三)呼吸室甲烷回收率之測定 31
1.測定步驟 31
2.甲烷氣體回收率 31
(四)甲烷日排放量計算 31
二、 試驗II芻料種類對台灣荷蘭種泌乳牛營養分消耗量、消化率、瘤胃內揮發性脂肪酸濃度、泌乳量及甲烷生成量的影響 32
(一) 試驗設計與處理 32
(二) 試驗動物及飼養管理 32
(三) 樣品之收集與製備 36
1.飼料成分及消耗量 36
2.糞便 36
3.尿液 36
4.乳樣 37
5.甲烷氣體 37
6.瘤胃液 37
(四) 化學分析 39
1.乾物質（Dry matter, DM）含量之測定 39
2.總能（Gross energy, GE）之測定 39
3.粗蛋白（Crude protein, CP）含量之測定 40
4.有機物（Organic matter, OM）含量之測定 41
5.纖維含量之測定： 42
6.揮發性脂肪酸（Volatile fatty acid, VFA）含量之測定 47
(五) 統計分析 50
三、 試驗III芻料種類對台灣荷蘭種非泌乳牛營養分消耗量、消化率、瘤胃內揮發性脂肪酸濃度及甲烷生成量的影響 51
(一) 試驗設計與處理 51
(二) 試驗動物及飼養管理 51
(三) 樣品之收集與置備 52
1.飼料成分及採食量 52
2.糞便、尿液及甲烷氣體 52
3.瘤胃液 52
(四) 化學分析 52
(五) 統計分析 53
陸、結果與討論 54
一、 試驗I 54
(一) 以簡易開放式呼吸室測定甲烷濃度之可行性 54
二、 試驗II 57
(一) 芻料種類對臺灣荷蘭種泌乳牛體重變化、營養分攝取量、消化率之影響 57
(二) 芻料種類對臺灣荷蘭種泌乳牛泌乳量及乳成分之影響 61
(三) 芻料種類對臺灣荷蘭種泌乳牛氮及能量蓄積之影響 63
(四) 芻料種類對臺灣荷蘭種泌乳牛瘤胃性狀之影響 66
(五) 芻料種類對臺灣荷蘭種泌乳牛甲烷排放量、能量損失、甲烷能量轉換係數、二氧化碳當量及排碳量之影響 68
三、 試驗III 74
(一) 芻料種類對臺灣荷蘭種非泌乳牛體重變化、營養分攝取量、消化率及氮蓄積與能量蓄積之影響 74
(二) 芻料種類對臺灣荷蘭種非泌乳牛瘤胃性狀之影響 78
(三) 芻料種類對臺灣荷蘭種非泌乳牛甲烷排放量、甲烷轉換因素、二氧化碳當量及排碳量之影響 80
柒、結論 84
捌、参考文獻 85


表 次

表1. 主要與代表性溫室氣體於大氣中之濃度、每年成長速率、停留時間及溫室效應潛力 7
Table 1. Atmospheric concentrations and current annual growth rate, lifetimes and global warming potential (GWP) of the major greenhouse gases and other groups’representative gases 7
表2. 牛隻體內醱酵之甲烷排放係數 8
Table 2. Enteric fermentation emission factors for cattle 8
表 3. 臺灣畜牧業腸道醱酵之甲烷排放統計（1990-2007年） 11
Table 3. Methane emissions of enteric fermentation from livestocks and poultries in Taiwan 11
表4. 百慕達乾草、燕麥乾草、玉米青貯料、泌乳精料及乾乳精料之化學分析值 34
Table 4. Chemical compositions of bermuda hay, oat hay, corn silage and concentrates fed to lactating and non-lactaing cows 34
表5. 試驗期間簡易開放式呼吸室及牛舍之溫、濕度狀態 56
Table 5. The daily temperature and relative humidity change in brief open-circuit chamber and animal house during the experimental period 56
表 6. 芻料種類對臺灣荷蘭種泌乳牛營養分及飲水消耗量及體重變化之影響 59
Table 6. Effect of dietary forages on daily consumption of nutrients and water and body weight gain of Holstein lactating cows in Taiwan 59
表 7. 芻料種類對臺灣荷蘭種泌乳牛營養分表面消化率之影響 60
Table 7. Effect of dietary forages on apparent digestibilities of nutrients of Holstein lactating cows in Taiwan 60
表8. 芻料種類對臺灣荷蘭種泌乳牛泌乳量及乳成分之影響 62
Table 8. Effect of dietary forages on milk production and compositions of Holstein lactating cows in Taiwan 62
表9. 芻料種類對臺灣荷蘭種泌乳牛氮及能量之蓄積之影響 65
Table 9. Effect of dietary forages on nitrogen and energy retentions of Holstein lactating cows in Taiwan 65
表10. 芻料種類對臺灣荷蘭種泌乳牛瘤胃之pH值及VFA濃度之影響 67
Table 10. Effect of dietary forages on rumen pH and VFA concentration of Holstein lactating cows in Taiwan 67
表 11. 芻料種類對臺灣荷蘭種泌乳牛甲烷排放量之影響 72
Table 11. Effect of dietary forages on methane emissions from Holstein lactating cows in Taiwan 72
表 12. 芻料種類對臺灣荷蘭種泌乳牛甲烷轉換因數、二氧化碳當量及排碳量之影響 73
Table 12. Effect of dietary forages on methane conversion factors, CO2eq and carbon emissions from Holstein lactating cows in Taiwan 73
表 13. 芻料種類對臺灣荷蘭種非泌乳牛營養分與飲水之消耗量及體重變化之影響 75
Table 13. Effect of dietary forages on daily consumption of nutrients and water and body weight gain of Holstein non-lactating cows in Taiwan 75
表 14. 芻料種類對臺灣荷蘭種非泌乳牛營養分消化率之影響 76
Table 14. Effect of dietary forages on apparent digestibilities of nutrients of Holstein non-lactating cows in Taiwan 76
表 15. 芻料種類對臺灣荷蘭種非泌乳牛氮及能量之蓄積之影響 77
Table 15. Effect of dietary forages on nitrogen and energy retentions of Holstein non-lactating cows in Taiwan 77
表 16. 芻料種類對臺灣荷蘭種非泌乳牛瘤胃之pH值及VFA濃度之影響 79
Table 16. Effect of dietary forages on rumen pH and VFA concentration of Holstein non-lactating cows in Taiwan 79
表 17. 芻料種類對臺灣荷蘭種非泌乳牛甲烷排放量之影響 82
Table 17. Effect of dietary forages on methane emissions from Holstein non-lactating cows in Taiwan 82
表.18. 芻料種類對臺灣荷蘭種非泌乳牛甲烷轉換因數、二氧化碳當量及排碳量之影響 83
Table 18. Effect of dietary forages on methane conversion factors, CO2eq and carbon emissions from Holstein non-lactating cows in Taiwan 83

 
圖 次

圖 1. 反芻動物體內氮化合物之消化與代謝。 14
Figure 1. Nitrogen metabolism in the ruminant. 14
圖2. 瘤胃中碳水化合物醱酵後之主要終產物。 15
Figure 2. Principal end products of the carbohydrate fermentation in the rumen. 15
圖3. 二氧化碳還原至甲烷之路徑。 19
Figure 3. The pathway of CO2-reduction to CH4 19
圖4. 禾本科植物隨成熟階段增加之化學組成分變化。 21
Figure 4. Chemical composition of grass with advancing maturity. 21
圖5. 自動偵測溫溼度及氣壓之紀錄器。 27
Figure 5. Data logger for detecting temperature, humidity and air pressure. 27
圖6. 簡易開放式呼吸室之外觀。 28
Figure 6. Appearance of the brief open-circuit chamber. 28
圖7. 甲烷標準品之檢量線。 30
Figure 7. The standard curve for methane analysis. 30
圖8. 開放式呼吸室（A）與其內之試驗牛隻（B）。 35
Figure 8. The brief open-circuit chamber (A) and the cattle inside (B). 35
圖9. 揮發性脂肪酸標準品之層析圖。 49
Figure 9. The chromatograms of volatile fatty acid standards. 49

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