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1.
异戊酸对西门塔尔牛瘤胃发酵及尿嘌呤衍生物的影响   总被引:2,自引:0,他引:2  
选用4头体重(420±8.6)kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究异戊酸(0、0.02、0.04和0.06 g/kgW)对瘤胃pH、NH3-N、VFA、营养物质降解率及尿嘌呤衍生物浓度的影响。结果表明:0.06 g/kgW组显著降低瘤胃pH(P<0.05),饲喂后3-6 h,0.04 g/kgW组和0.06 g/kgW组NH3-N浓度显著低于对照和0.02 g/kgW组(P<0.05);0.04 g/kgW组和0.06 g/kgW组,豆粕干物质、有机物质和粗蛋白质有效降解率显著低于对照(P<0.05);0.04 g/kgW组玉米秸秆干物质、有机物质、中性洗涤纤维和酸性洗涤纤维的有效降解率显著提高(P<0.05),0.04 g/kgW组瘤胃乙酸、丁酸、乙酸/丙酸比例、总挥发性脂肪酸和尿嘌呤衍生物显著增加(P<0.05)。异戊酸的适宜添加水平为0.04g/kgW。  相似文献   

2.
异丁酸对西门塔尔牛瘤胃发酵及尿嘌呤衍生物的影响   总被引:4,自引:0,他引:4  
本文旨在研究异丁酸对西门塔尔牛瘤胃pH、NH3-N、VFA和营养物质降解率及尿嘌呤衍生物浓度的影响。选用4头平均体重420 kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计,以混合精料和风干玉米秸秆为基础日粮,在基础日粮中分别添加异丁酸0、0.02、0.04和0.06 g/(kgW.d)。结果表明:各组瘤胃pH差异不显著(P>0.05),0.04 g/(kgW.d)组和0.06 g/(kgW.d)组NH3-N浓度极显著低于对照和0.02 g/(kgW.d)组(P<0.01);0.02 g/(kgW.d)组豆粕干物质、有机物和粗蛋白质动态降解率显著高于对照组(P<0.05);0.04 g/(kgW.d)组玉米秸干物质、有机物、中性洗涤纤维和酸性洗涤纤维的降解率显著提高(P<0.05),0.04 g/(kgW.d)组瘤胃乙酸、乙酸/丙酸、总挥发性脂肪酸和尿嘌呤衍生物显著增加(P<0.05)。根据试验结果推断日粮中异丁酸的适宜添加水平为0.04 g/(kgW.d)。  相似文献   

3.
异丁酸对西门塔尔牛瘤胃营养物质降解的影响   总被引:1,自引:0,他引:1  
选用4头平均体重420kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛(阉牛),采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究日粮添加异丁酸(0、0.02g/kgWd-1、0.04g/kgWd-1和0.06g/kgWd-1)对瘤胃营养物质降解的影响。结果表明:0.02g/kgWd-1组豆粕干物质、有机物和粗蛋白质动态降解率显著高于对照组(P<0.05);0.04g/kgWd-1组玉米秸干物质、有机物、中性洗涤纤维和酸性洗涤纤维的降解率显著提高(P<0.05)。根据本试验结果推断日粮中异丁酸的适宜添加水平为0.04g/kgWd-1。  相似文献   

4.
选用4头体重500 kg,年龄3.5岁装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究丙酸钙(0、100、200 g/d和300 g/d)对玉米秸秆瘤胃降解率的影响.结果表明:200 g/d组玉米秸秆干物质(DM)瘤胃有效降解率较对照组提高,但差异不显著(P>0.05),有机物(OM)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)瘤胃有效降解率较对照组显著提高(P<0.05).本试验结果表明,日粮中丙酸钙的适宜添加水平为200 g/d.  相似文献   

5.
王聪  黄应祥  刘强  王浩  任建民 《饲料工业》2007,28(13):48-49
试验选用4头装有永久性瘤胃瘘管的西门塔尔牛阉牛。采用4×4拉丁方设计,分5期试验测定异丁酸、异戊酸、2-甲基丁酸、戊酸及混合酸(每天每千克体重0、0.02、0.04和0.06g)对纤维物质消化率的影响。结果表明:日粮添加支链脂肪酸或混合酸后,0.04g/kg异丁酸、2-甲基丁酸或戊酸组中性洗涤纤维和酸性洗涤纤维消化率显著高于对照组(P<0.05);异戊酸或混合酸处理组中性洗涤纤维和酸性洗涤纤维消化率显著高于对照组(P<0.05),0.04g/kg组显著高于0.02g/kg组(P<0.05)。添加各种支链脂肪酸在0.04g/kg对纤维物质消化有显著促进作用,因此适宜添加水平为0.04g/kg。  相似文献   

6.
选用4头年龄3.5岁,体况良好,体重(500±20)kg的中国西门塔尔牛阉牛,采用4×4拉丁方设计,研究日粮添加丙酸镁(100 g/d)、丙酸(87 g/d)和氧化镁(24 g/d)对玉米秸秆干物质(DM)、有机物质(OM)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)瘤胃降解率的影响。结果表明:日粮添加丙酸镁、丙酸和氧化镁对玉米秸秆DM、OM瘤胃有效降解率(P)无显著影响(P>0.05);玉米秸秆NDF瘤胃慢速降解部分(b)和降解常数(c)及ADF降解常数(c)差异不显著(P>0.05),丙酸镁组ADF瘤胃慢速降解部分(b)较对照组显著降低(P<0.05),NDF和ADF瘤胃快速降解部分(a)和瘤胃有效降解率(P)较对照组显著提高(P<0.05)。日粮添加丙酸镁提高了玉米秸秆NDF和ADF瘤胃有效降解率(P)。  相似文献   

7.
试验选用4头装有永久性瘤胃瘘管的西门塔尔阉牛。采用4×4拉丁方设计,分5期试验测定异丁酸、异戊酸、2-甲基丁酸、戊酸及混合酸(0、0.02、0.04和0.06g/kgW)对牛日粮有机物质和粗蛋白质消化率的影响。结果表明,日粮添加支链脂肪酸或混合酸后,0.04和0.06g/kgW组OM消化率显著高于对照组,处理组CP消化率显著高于对照组,由此判定添加各种支链脂肪酸在0.04g/kgW对营养物质消化有显著促进作用。  相似文献   

8.
选用4头3.5岁,体重500 kg装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4x4拉丁方设计,以混合精料和玉米青贮为基础日粮,研究过瘤胃蛋氨酸、硬脂酸和蛋氨酸对玉米秸秆瘤胃降解率的影响.结果表明:过瘤胃蛋氨酸组玉米秸秆干物质(DM)、有机物(OM)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃有效降解率(P)和降解速度常数(C)较对照组显著提高(P<0.05).日粮添加过瘤胃蛋氨酸可以有效提高玉米秸秆瘤胃有效降解率,提高劣质玉米秸秆的利用率.  相似文献   

9.
日粮补充苹果酸对牛瘤胃发酵和养分消化代谢的影响   总被引:8,自引:4,他引:4  
选用8头体重462 kg、年龄3岁、装有永久性瘤胃瘘管的西门塔尔牛阉牛,采用4×4重复拉丁方设计,对照组饲喂基础日粮,处理组分别在基础日粮基础上添加苹果酸70,140和210 g/d,研究苹果酸对西门塔尔牛瘤胃发酵、尿嘌呤衍生物含量、日粮养分表观消化率、能量代谢及氮平衡的影响。结果表明,140和210 g/d组瘤胃pH值显著低于对照组,瘤胃乙酸摩尔比、乙酸/丙酸、氨态氮浓度和乳酸含量显著低于对照组和70 g/d组(P<0.05),瘤胃总挥发性脂肪酸浓度、丙酸和丁酸摩尔比显著高于对照组和100 g/d组(P<0.05)。140 g/d组玉米秸秆干物质、有机物质、中性洗涤纤维和酸性洗涤纤维瘤胃有效降解率显著高于对照组(P<0.05);210 g/d组混合精料干物质、有机物质和粗蛋白质瘤胃有效降解率显著低于对照组、70和140 g/d组(P<0.05)。140 g/d组尿囊素和尿嘌呤衍生物含量显著高于70和210 g/d组及对照组(P<0.05);140和210 g/d组有机物质、粗脂肪、无氮浸出物、中性洗涤纤维和酸性洗涤纤维表观消化率显著高于对照组(P<0.05);140 g/d组消化能、代谢能、沉积能及沉积能/消化能显著高于对照组(P<0.05);140 g/d组沉积氮显著高于对照组(P<0.05)。综合各项指标,苹果酸的适宜添加水平为140 g/d。  相似文献   

10.
选用4头体重420 kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究异戊酸(0、0.02、0.04和0.06 g/kg体重)对瘤胃pH、氨态氮、挥发性脂肪酸浓度及乙酸/丙酸比例的影响。结果表明:0.06 g/kg体重组显著降低瘤胃pH(P<0.05),饲喂后3~6 h 0.04 g/kg体重组和0.06 g/kg体重组NH3-N浓度显著低于对照组和0.02 g/kg体重组(P<0.05);0.04 g/kg体重组瘤胃乙酸、丁酸和总挥发性脂肪酸浓度显著增加(P<0.05),乙酸/丙酸比例显著提高(P<0.05)。异戊酸的适宜添加水平为0.04 g/kg体重。  相似文献   

11.
本试验旨在评定棉粕与豆粕的干物质(DM)、有机物(OM)、粗蛋白质(CP)在绵羊瘤胃内的降解动力学参数变化及瘤胃降解前后有效赖氨酸的含量变化。选用3只安装有永久性瘤胃瘘管的体重为(28.0±2.97)kg的育肥哈萨克公羊,代谢笼内单笼饲喂,每天饲喂棉籽壳200 g、精料500 g、小麦秸500 g,余料不超过10%。采用尼龙袋技术评定棉粕与豆粕DM、OM及CP的降解动力学参数,计算有效降解率(ED)及瘤胃停留时间(RRT),染料结合法(DBL)测定有效赖氨酸的含量。结果表明,在瘤胃固相食糜的平均外流速度为1.84%/h条件下,豆粕DM、OM及CP的瘤胃降解率及有效降解率均高于棉粕,而瘤胃停留时间均短于棉粕。豆粕经瘤胃内培养16 h后有效赖氨酸含量略有升高,而棉粕无明显变化。该试验结果为进一步评定棉粕及豆粕养分的小肠消化率提供参考。  相似文献   

12.
Objectives of this research were to evaluate effects of increasing level of barley supplementation on forage intake, digestibility, and ruminal fermentation in beef steers fed medium-quality forage. Four crossbred ruminally cannulated steers (average initial BW = 200 +/- 10 kg) were used in a 4 x 4 Latin square design. Chopped (5 cm) grass hay (10% CP) was offered ad libitum with one of four supplements. Supplements included 0, 0.8, 1.6, or 2.4 kg of barley (DM basis) and were fed in two equal portions at 0700 and 1600. Supplements were fed at levels to provide for equal intake of supplemental protein with the addition of soybean meal. Forage intake (kg and g/kg BW) decreased linearly (P < 0.01), and total intake increased linearly (P < 0.03) with increasing level of barley supplementation. Digestible OM intake (g/kg BW) increased linearly (P < 0.01) with increasing level of barley supplementation; however, the majority of this response was observed with 0.8 kg of barley supplementation. Treatments had only minor effects on ruminal pH, with decreases occurring at 15 h after feeding in steers receiving 2.4 kg of barley supplementation. Total-tract digestibility of DM, OM, NDF, and CP were increased (P < 0.04) with barley supplementation; however, ADF digestibility was decreased by 1.6 and 2.4 kg of barley supplementation compared with controls. Ruminal ammonia concentrations decreased linearly (P < 0.01) at 1 through 15 h after feeding. Total ruminal VFA concentrations were not altered by dietary treatments. Ruminal proportions of acetate and butyrate decreased (P < 0.10) in response to supplementation. Rate, lag, and extent (72 h) of in situ forage degradability were unaffected by treatment. Generally, these data are interpreted to indicate that increasing levels of barley supplementation decrease forage intake, increase DM, OM, and NDF digestibility, and indicate alteration of the ruminal environment and fermentation patterns.  相似文献   

13.
Whole crop rice was harvested 120 days after planting and chopped to 2–3-cm length for silage making. The whole crop rice silage (WCRS) was supplemented with different levels of molasses and urea to study nutritive value and in situ rumen degradability. The ensiling study was randomly assigned according to a 6?×?5 factorial arrangement, in which the first factor was molasses (M) supplementation at M0, M1, M2, M3, M4, and M5 %, and the second was urea (U) supplementation at U0, U0.5, U1.0, U1.5, and U2.0 % of the crop dry mater (DM), respectively. After 45 days of ensiling, temperature, pH, chemical composition, and fermentation end products of the silages were measured. Ten U and M treatment combinations of WCRS were subsequently selected to study rumen degradability by nylon bag technique. The results showed that temperature and pH of the silages linearly increased with U supplementation level, while total volatile fatty acid (TVFA), acetic acid (C2) and propionic acid (C3) decreased. In contrast, increasing level of M supplementation decreased WCRS temperature and pH, whereas TVFA, C2, and C3 concentrations increased dramatically. Both M and U supplementation increased concentration of butyric acid (C4). Dry matter, organic matter (OM), and acid detergent fiber (ADF) contents of the silages were not influenced by either M or U supplementation. Increasing U supplementation increased crude protein (CP) content, while M level did not show any effect. Furthermore, neutral detergent fiber (NDF) content in silage was decreased by both M and U supplementation. The results of the in situ study showed that M and U supplementation increased both ruminal DM and OM degradation. The water-soluble fraction (a) was the highest in WCRS U1.5M3 and lowest in U0M0. Increasing M and U supplementation levels increased the potentially degradable fraction (b) of both DM and OM. Total rumen degradable fraction (a?+?b) was highest in WCRS U1.5M3, whereas OM degradability was highest in U0M3. However, effective degradation of both DM and OM were the highest in WCRS U1.5M3 and the lowest in U0M0. We conclude that supplementation of U and M increases WCRS quality and rumen degradability. Supplementation of U at 1.5 and M at 3–4 % of the crop DM is recommended for lactating dairy cows and fattening beef cattle.  相似文献   

14.
The objective of this study was to evaluate the effects of isovalerate supplementation on rumen fermentation, urinary excretion of purine derivatives and feed digestibility in the total tract of steers. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were: control (without isovalerate), low isovalerate (LIV), medium isovalerate (MIV) and high isovalerate (HIV) dosage of isovalerate at 100, 200 and 300 mg isovalerate per kg dry matter (DM) intake respectively. Diets consisted of corn stover and concentrate (60/40, DM basis). Dry matter intake was approximately 9 kg per day that was 90% of ad libitum intake including 5.4 kg corn stover and 3.6 kg concentrate. Ruminal pH (6.72–6.54) was linearly (p < 0.03) reduced, whereas total volatile fatty acid concentration (64.6–74.7 mmol/l) was linearly (p < 0.01) and quadratically (p < 0.01) increased with increasing isovalerate supplementation. Ratio of acetate to propionate increased linearly (p < 0.01) from 2.78 to 3.39 as isovalerate supplementation increased because of the increase in acetate production and decrease in propionate production. In situ ruminal degradation of amylase‐treated neutral detergent fibre (aNDF) of corn stover was improved, but crude protein (CP) degradability of soybean meal decreased with increasing isovalerate supplementation. Urinary excretion of purine derivatives was quadratically (p < 0.01) changed by altering isovalerate supplementation (50.5, 54.3, 58.9 and 55.2 mmol/day for control, LIV, MIV and HIV, respectively). Similarly, digestibilities of organic matter, aNDF and CP in the total tract were linearly and quadratically increased with increasing isovalerate supplementation. The results of this study indicate that supplementation of diet with isovalerate improved ruminal fermentation and feed digestion in beef cattle. It was suggested that the isovalerate stimulated the digestive micro‐organisms or enzymes in a dose‐dependent manner.  相似文献   

15.
试验旨在研究中药复方对日粮营养物质在山羊瘤胃内降解特性的影响。择6头健康的体重相近的安装有永久性瘤胃瘘管的周岁大足黑山羊羯羊,按3×3重复拉丁方试验设计,随机分为3组,1个对照组和2个处理组。对照组饲喂基础日粮,2个处理组分别在基础日粮上给每头羊日喂15 g复方Ⅰ和复方Ⅱ(由藿香、苍术、黄柏和生石膏等中药按不同比例组成)。采用瘤胃尼龙袋法对日粮精料和粗料干物质(DM)、有机物(OM)、粗蛋白质(CP)、中性洗涤纤维(NDF)及酸性洗涤纤维(ADF)在瘤胃内不同时间点的降解率进行测定,再根据动态降解率计算出降解模型参数及有效降解率。结果表明:复方Ⅰ能极显著提高精料DM和ADF及粗料DM、OM、NDF和ADF的有效降解率(P<0.01);复方Ⅱ能极显著提高精料DM及粗料DM、OM和ADF的有效降解率(P<0.01),显著提高精料ADF和粗料NDF的有效降解率(P<0.05)。研究结果提示,中药复方能改善山羊瘤胃降解能力,且复方Ⅰ作用效果优于复方Ⅱ。  相似文献   

16.
The objective of the study was to evaluate the effects of spices on forage utilization and nitrogen (N) emission using in vitro and in vivo approach. A 6 × 5 factorial triplicate arrangement was used to assess the in vitro degradability of rice straw with control (without spices) and individual (40 mg/g rice straw) spices (cumin, coriander, clove, black cumin, turmeric) at five different incubation times. In vitro dry matter (DM) and organic matter (OM) degradability of rice straw were highest in presence of spices except for clove. Clove significantly reduced the total volatile fatty acids concentration, molar proportion of acetate and propionate ratio, but increased propionate production. Acetate and butyrate production were not affected by treatments. The ammonia‐nitrogen concentration was lowest for clove and turmeric compared to other spices. Rumen pH was unchanged but gradually decreased over the incubation period. For in vivo study, 12 bucks with average live weight 7.65 ± 0.19 kg were assigned to a completely randomized design with three treatments and four replicates for a 28‐day period. Bucks were fed a total mixed ration without (0 g/kg DM) or with (2.5, 7.5 g/kg DM) clove supplementation. DM intake, body weight and apparent total tract digestibility of crude protein (CP) and acid detergent fibre (ADF) were not affected by increasing dietary doses of clove but tended (= .09) to increase DM and OM digestibility. The urinary N and urine urea N concentration of bucks decreased linearly with incremental doses of clove diet. In contrary, clove supplementation had positive effects on plasma urea N and retained N in bucks. We concluded that though some spices had positive effects on ruminal digestion and fermentation, the dosage level assessed in the current study (up to 7.5 g/kg DM clove) can be promoted as an effective dietary approach to mitigate N losses in bucks.  相似文献   

17.
本试验以优良中筋小麦“扬麦14”为试验材料,在小麦整个生育期提高CO2浓度和温度,分为4组:空白组,升温组,CO2组,升温和CO2混合组,空白组小麦生长平均温度10.5 ℃,CO2浓度413 μmol/mol,升温组温度高于空白组2 ℃,CO2组浓度500 μmol/mol,升温和CO2混合组同时提高温度与CO2浓度,收割时采集麦秸用于体内消化试验。用3头装有永久性瘤胃瘘管的荷斯坦奶牛,采用尼龙袋法评定温度和CO2浓度升高环境下小麦秸瘤胃的降解特性。结果显示,与空白组相比,升温组DM快速降解部分显著升高(P<0.05),ADF降解率与ADF慢速降解部分显著降低(P<0.05);CO2组DM,OM,NDF及ADF降解率均显著降低(P<0.05),且DM,OM与NDF有效降解率显著降低(P<0.05);混合组DM,OM,NDF及ADF降解率均显著降低(P<0.05),DM,OM及ADF慢速降解部分显著降低(P<0.05),DM,OM与NDF有效降解率显著降低(P<0.05)。不同处理后麦秸DM,OM,NDF与ADF瘤胃内降解率从高到低为空白组、升温组、CO2组和混合组。综合以上结果表明,温度和CO2浓度升高降低了麦秸DM,OM,NDF及ADF瘤胃内降解率,导致麦秸营养价值降低,温度升高对降解率影响最小,其次为CO2浓度升高,温度和CO2浓度同时升高对麦秸营养价值的影响最为显著。  相似文献   

18.
Seven cannulated (rumen and duodenal) Angus x Hereford steers (264 +/- 8 kg BW) consuming low-quality forage (5% CP; 61% NDF; 31% ADF) were used to determine the influence of CP degradability and supplementation frequency (SF) on DMI and nutrient digestion. Treatments included an unsupplemented control and degradable intake protein (DIP) or undegradable intake protein (UIP) provided daily, every 3 d, or every 6 d. The DIP treatments (18% UIP) were calculated to provide 100% of the DIP requirement, while the UIP treatments (60% UIP) were provided on an isonitrogenous basis compared with DIP. Forage DMI was not affected by treatment. Total DM and N intake, duodenal N flow, and intestinal N disappearance increased (P < 0.01) with supplementation. Dry matter intake and duodenal N flow responded quadratically (P < 0.04; greatest values on the every-third-day treatments) as SF decreased. However, no differences in N intake or intestinal N disappearance were observed because of CP degradability or SF. Duodenal bacterial N flow and true bacterial N synthesis (g bacterial N/kg of OM truly digested in the rumen) were increased (P < 0.05) with supplementation. Also, duodenal bacterial N flow was greater (P < 0.05) for DIP compared with UIP. Duodenal nonbacterial N flow was increased (P = 0.02) with CP supplementation and for UIP compared with DIP (P < 0.01). Supplemental CP increased (P < 0.01) total tract DM and N digestibility with no difference due to CP degradability or SF. Results suggest CP supplements consisting of 20 to 60% UIP can be effectively used by steers consuming low-quality forage without adversely affecting DMI, nutrient digestibility, or bacterial CP synthesis, even when provided as infrequently as once every 6 d.  相似文献   

19.
Seasonal chemical composition and ruminal organic matter (OM) and crude protein (CP) degradabilities were determined in four tropical multi-purpose tree species (MPTS) namely; Pterocarpus santalinoides, Grewia pubescens, Enterolobium cyclocarpum and Leucaena leucocephala. Three West African dwarf (WAD) rams fitted with permanent rumen cannula were used for the degradability trials. Foliage samples were collected four times to represent seasonal variations as follows: January--mid dry; April--late dry; July--mid rainy and October--late rainy seasons. Leaf samples were randomly collected from the trees for estimation of dry matter (DM) and chemical composition. Ruminal in sacco OM and CP degradabilities were estimated from residues in nylon bags. All samples had high CP (161-259 g/kg DM) and moderate fibre concentrations [neutral detergent fibre (without residual ash], 300-501 g/kg DM; acid detergent fibre (without residual ash), 225-409 g/kg DM and acid detergent lignin, 87-179 g/kg DM across seasons. Interaction effects of species and season on chemical composition were highly significant (p = 0.001) except for trypsin inhibitor (p = 0.614). The MPTS recorded more than 60% OM and CP degradability at 24 h, which implied that they were all highly degradable in the rumen. Their incorporation into ruminant feeding systems as dry season forage supplements is therefore recommended.  相似文献   

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