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1.
体外产气法评价青海高原反刍家畜常用粗饲料组合效应   总被引:1,自引:0,他引:1  
采用体外产气法评价青海高原反刍家畜的3种常用粗饲料青贮玉米(Zea mays)秸秆、苜蓿(Medicago sativa)青干草和燕麦(Arrhenatherum elatius)青干草按0∶100、25∶75、50∶50、75∶25和100∶0的比例两两组合时的发酵特性。结果表明,理论最大产气量、48 h产气量分别与中性洗涤可溶物/粗蛋白(NDS/CP)(P<0.001)、有机物(OM)(P<0.01),中性洗涤可溶物(NDS)(P<0.05)呈正相关关系,分别与酸性洗涤纤维(ADF)(P<0.001)、中性洗涤纤维(NDF)(P<0.05)和粗蛋白(CP)(P<0.05)呈负相关关系;产气速率常数分别与OM(P<0.001)、NDS(P<0.001)和NDS/CP(P<0.01)呈正相关关系,分别与ADF、NDF均呈极显著负相关关系(P<0.001);产气延滞时间与ADF(P<0.01)和NDF(P<0.05)呈正相关关系,分别与OM(P<0.01)、NDS(P<0.05)和NDS/CP(P<0.05)呈负相关关系,说明了组合牧草体外发酵产气程度主要受非结构性碳水化合物与粗蛋白比例的影响。3种粗饲料两两组合搭配时,青贮玉米秸秆与苜蓿青干草以25∶75比例、青贮玉米秸秆与燕麦青干草以50∶50比例、苜蓿青干草与燕麦青干草以25∶75或50∶50比例组合时较为合适,且随着发酵时间的延长,各组合均呈现组合效应量逐渐减弱的变化趋势。  相似文献   

2.
利用体外产气法研究了羊草中性洗涤纤维(NDF)、苜蓿NDF和玉米青贮NDF与豆粕组合体外发酵特性及组合效应.结果表明:体外评价时,所有的组合均发生正的组合效应.羊草NDF与豆粕组合时,当NDF/CP为3.4出现显著正组合效应.在NDF/CP为2.6时有最大正效应值发生;苜蓿NDF与豆粕组合时.当NDF/CP为3.0出现显著的正组合效应,最大正效应值发生在NDF/CP为2.6;青贮NDF与豆粕组合时,当NDF/CP为3.8时出现显著的正组合效应,最大正效应发生在NDF/CP为1.8.随着蛋白质比例的提高,正效应也提高,在一定的NDF/CP值(2.6)时达到最大值,随着蛋白质比例的再次提高,正效应又有下降.  相似文献   

3.
体外瘤胃发酵法评定不同类型饲料的营养价值   总被引:1,自引:0,他引:1  
本试验旨在利用体外瘤胃发酵法评定不同类型饲料的营养价值。试验1比较了不同粗饲料(麦壳、羊草、稻草、高能饲草、美国苜蓿、国产苜蓿、全株玉米青贮、花生秧青贮、玉米秸青贮和杂交高粱青贮)的体外发酵特性,试验2比较了不同蛋白质饲料(豆粕、棉籽粕、菜籽粕、芝麻粕和棕榈粕)的体外发酵特性,试验3比较了不同饲料组合(稻草组合、苜蓿组合、羊草组合和麦壳组合,各组合精料相同)的体外发酵特性。结果表明:玉米青贮(包括全株玉米青贮和玉米秸青贮)和苜蓿(包括美国苜蓿和国产苜蓿)体外发酵48 h的产气量(GP)、干物质降解率(DMD)和总挥发性脂肪酸(TVFA)浓度均显著高于其他粗饲料(P<0.05);麦壳的GP和DMD则显著低于其他粗饲料(P<0.05)。豆粕体外发酵48 h的GP最高,其发酵速度最快。不同蛋白质饲料的有机物降解率(OMD)和DMD差异较大,以豆粕的OMD与DMD最高,显著高于其他蛋白质饲料(P<0.05);微生物蛋白(MCP)浓度也以豆粕最高,显著高于芝麻粕和棕榈粕(P<0.05)。对于不同饲料组合,中性洗涤纤维与粗蛋白质比值(NDF/CP)越小,其发酵速度越快、降解率越高。相关性分析显示,NDF/CP与DMD呈显著负相关(P<0.05)。结果提示:1)对于粗饲料,玉米青贮和苜蓿类饲料的体外发酵GP较高,发酵速度较快;麦壳的体外发酵GP较低,发酵速度较慢。2)对于蛋白质饲料,豆粕的体外发酵GP、发酵速度和MCP浓度均高于其他蛋白质饲料。3)对于饲料组合,NDF/CP会影响体外发酵特性,NDF/CP越小,其发酵延滞期越短、发酵速度越快、降解率越高。  相似文献   

4.
采用3×3正交试验设计对黄贮发酵参数(黄贮菌种,黄贮周期,辅料)进行优化,发酵底物为小麦秸秆,发酵完成后对各组贮料进行优化指标pH值的评定,从而确定小麦秸秆黄贮的最优水平组合.之后应用最优组合方案对玉米、油菜秸秆进行发酵,测定小麦、玉米、油菜3种秸秆在发酵前后营养价值(DM、CP、NDF、ADF、Ash、OMD)的变化.结果显示:小麦秸秆发酵完成后各处理组的pH值较处理前均有所降低;确定了以EM百益宝菌液为黄贮菌种,以35 d为黄贮周期,以玉米、麦麸、食盐、纤维素酶为辅料的最优组合方案;小麦秸秆发酵后DM、NDF含量较处理前极显著下降(P<0.01),ADF含量较处理前显著下降(P<0.05),Ash含量有所下降(P>0.05),CP含量和OMD有所升高(P>0.05);玉米秸秆发酵后NDF、ADF含量较处理前极显著下降(P<0.01),DM和Ash含量有所下降(P>0.05),CP含量极显著升高(P<0.01),OMD有所升高(P>0.05).  相似文献   

5.
为研究氮源和水平对肉牛瘤胃发酵特性的影响,本试验利用体外培养法研究不同水平(0、50、100和200 mg/L)的尿素、亮氨酸、异亮氨酸和缬氨酸对培养液pH、氨态氮、微生物蛋白质、挥发性脂肪酸的影响.结果表明:在体外培养条件下,以亮氨酸和异亮氨酸为氮源,培养液pH和微生物蛋白质浓度分别显著低于和显著高于以尿素为氮源(P<0.05),以支链氨基酸为氮源培养液氨态氮浓度显著低于以尿素为氮源(P<0.05),以异亮氨酸为氮源培养液总挥发性脂肪酸、乙酸和丙酸浓度都显著高于其他氮源(P<0.05);随着氮水平的提高,培养液pH以及氨态氮、微生物蛋白质和丙酸的浓度都显著的升高(P<0.05);氮源和水平对各指标均存在显著的互作效应(P<0.05).结果提示,亮氨酸作为氮源更有利于微生物蛋白质的合成;200 mg/L的氮水平有利于瘤胃微生物的发酵;氮源和水平对瘤胃发酵存在互作效应.  相似文献   

6.
为研究不同比例藜麦青干草制成的颗粒饲料对藏羊育肥效果及表观消化率的影响,采用单因素随机设计试验,选取月龄接近、健康状况良好、发育正常的48只藏羊作为试验羊,分为4组,每组4个重复。对照组粗饲料为100%玉米秸秆|试验1组粗饲料由33%藜麦青干草+67%玉米秸秆组成|试验2组粗饲料由67%藜麦青干草+33%玉米秸秆组成|试验3组粗饲料为100%藜麦青干草。结果表明:藜麦青干草与玉米秸秆为粗饲料制成颗粒料时,能提高饲料的采食量和采食积极性,其对藏羊体增重的影响与玉米秸秆相比无明显差异(P > 0.05),日粮中添加比例为30%时效果最佳,提升水平为3.18%。全价颗粒料中藜麦青干草添加比例为30%时,藏羊对颗粒饲料中中性洗涤纤维(NDF)的表观消化率较低,与对照组相比降低了19.84%,差异显著(P < 0.05)。其他组别藏羊对于全价饲料干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)、NDF、酸性洗涤纤维(ADF)的表观消化率未达到统计显著水平(P > 0.05)。综上所述,藜麦青干草制成的颗粒饲料与传统玉米秸秆颗粒饲料相比,采食率、表观消化率并无显著差异,可用于传统秸秆作物的替代饲料,可有效提高饲料利用率,减少浪费,藜麦青干草作为粗饲料,可减少精料添加,提高地区内藜麦干草的利用率。 [关键词] 藜麦|藏羊|颗粒饲料|育肥效果|表观消化率  相似文献   

7.
旨在研究全株玉米青贮(WCS)、小麦秸秆(WS)和苜蓿青贮(AS)不同组合比例对晋南牛瘤胃体外发酵特性的影响,筛选不同饲料组合应用的最适比例。将全株玉米青贮、小麦秸秆、苜蓿青贮以不同比例组合(80∶10∶10, 70∶10∶20, 70∶20∶10, 60∶10∶30, 60∶20∶10, 60∶30∶10, 50∶10∶40, 50∶20∶30, 50∶30∶20, 50∶40∶10, 0∶100∶0, 100∶0∶0, 0∶0∶100)进行体外发酵试验,测定分析不同饲料组合对体外产气量(GP)、干物质降解率(IVDMD)、pH、氨态氮(NH3-N)、挥发性脂肪酸(VFA)的影响,计算各组合的单项组合效应值(SFAEI)和综合组合效应值(MFAEI)。结果表明,全株玉米青贮、小麦秸秆和苜蓿青贮的组合比例对GP的影响极显著(P<0.01)。随着全株玉米青贮比例增加,GP逐渐增加。各组体外发酵液pH保持为6.68~6.89(P<0.01)。NH3-N的变化范围为14.31~26.01 mg·100 mL-1P<0.01)。全株玉米青贮比例一定时,IVDMD随着苜蓿青贮比例增加而增加。不同比例组合的全株玉米青贮、小麦秸秆和苜蓿青贮体外发酵液中VFA浓度差异极显著(P<0.01)。60∶30∶10组乙酸和总挥发性脂肪酸(TVFA)浓度显著高于其他各组(P<0.05),其丙酸浓度也为最高(13.99 mmol·L-1)。各比例组合乙酸/丙酸在2.76~3.20,组间差异不显著(P>0.05)。不同组合的综合组合效应值均为正组合效应,70∶20∶10综合组合效应值(0.9343)最高。由此可见,全株玉米青贮、小麦秸秆和苜蓿青贮比例为70∶20∶10时,组合效应最佳。  相似文献   

8.
本试验旨在应用体外产气法研究玉米秸秆、稻草、玉米秸秆青贮与精料间的组合效应。采用单因素试验设计,进行3次组合筛选试验:首先进行玉米秸秆与稻草组合试验,筛选出最优玉米秸秆和稻草组合(玉米秸秆-稻草)比例;再进行玉米秸秆-稻草与玉米秸秆青贮组合试验,筛选出最优玉米秸秆-稻草和玉米秸秆青贮组合(玉米秸秆-稻草-玉米秸秆青贮)比例;最后进行玉米秸秆-稻草-玉米秸秆青贮与精料组合试验,筛选出最优玉米秸秆-稻草-玉米秸秆青贮与精料组合比例。各组合均分别以100.0∶0、80.0∶20.0、60.0∶40.0、50.0∶50.0、40.0∶60.0、20.0∶80.0、0∶100.0进行体外发酵试验,每个组合设3个重复。利用体外产气法分析不同饲料组合对48 h产气量、干物质消失率(DMD)、p H及微生物蛋白(MCP)、氨态氮(NH3-N)、挥发性脂肪酸(VFA)浓度的影响。计算各组合的单项组合效应指数(SFAEI)和多项组合效应指数(MFAEI)。结果表明:1)各饲料以不同比例组合对产气量均有显著或极显著影响(P0.05或P0.01),玉米秸秆∶稻草、玉米秸秆-稻草∶玉米秸秆青贮、玉米秸秆-稻草-玉米秸秆青贮∶精料产气量的SFAEI分别在60.0∶40.0、40.0∶60.0、20.0∶80.0时达最大值;2)各饲料以不同比例组合对DMD也存在显著或极显著影响(P0.05或P0.01),玉米秸秆∶稻草、玉米秸秆-稻草∶玉米秸秆青贮、玉米秸秆-稻草-玉米秸秆青贮∶精料DMD的SFAEI分别在50.0∶50.0、40.0∶60.0、20.0∶80.0时达最大值;3)不同玉米秸秆-稻草-稻草∶精料对p H有极显著影响(P0.01);4)各饲料以不同比例组合对MCP浓度也存在显著或极显著影响(P0.05或P0.01),玉米秸秆∶稻草、玉米秸秆-玉米秸秆青贮∶玉米秸秆青贮、玉米秸秆-稻草-玉米秸秆青贮∶精料产气量的SFAEI分别在80.0∶20.0、40.0∶60.0、20.0∶80.0时达最大值;5)各饲料以不同比例组合对NH3-N浓度也存在显著或极显著影响(P0.05或P0.01),范围在20.20~31.59 mg/d L;6)玉米秸秆与稻草组合的乙酸/丙酸和玉米秸秆-稻草-玉米秸秆青贮与精料组合丁酸浓度在各比例间差异不显著(P0.05),各饲料以不同比例组合对其余VFA和TVFA浓度也存在显著或极显著影响(P0.05或P0.01)。以MFAEI进行评定各饲料组合的最优比例如下:玉米秸秆与稻草为60.0∶40.0;玉米秸秆、稻草与玉米秸秆青贮为24.0∶16.0∶60.0;玉米秸秆、稻草、玉米秸秆青贮与精料为9.6∶6.4∶24.0∶60.0。  相似文献   

9.
文章旨在研究豆粕、牡丹籽粕、棉籽粕、棕榈粕、啤酒糟、豆渣、味精渣、玉米酒精糟(DDGS)、芝麻饼粕和葵花饼共10种蛋白质饲料原料的瘤胃降解特性。试验选用3头装有永久性瘤胃瘘管的鲁西牛×利木赞杂交牛为试验动物,采用尼龙袋法测定10种蛋白质饲料的干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)瘤胃降解率。结果表明:味精渣DM有效降解率最高,芝麻饼粕最低,各原料间差异显著(P <0.05);CP有效降解率为棉籽粕>牡丹籽粕>豆粕>味精渣>豆渣> DDGS>葵花粕>啤酒糟>棕榈粕>芝麻饼粕,各原料间显著差异(P <0.05);味精渣、棉籽粕和豆粕的NDF有效降解率较高,棕榈粕、啤酒糟和芝麻饼粕较低,各原料间差异显著(P <0.05);味精渣ADF有效降解率最高,其次为豆粕、棉籽粕和牡丹籽粕,均显著高于其他原料(P <0.05)。综上所述,不同来源蛋白质饲料具有不同的瘤胃降解特性,采用隶属函数进行综合营养评价,排序为味精渣>豆粕>棉籽粕> DDGS>牡丹籽粕>...  相似文献   

10.
奶牛主要饲料原料蛋白质瘤胃降解率的研究   总被引:2,自引:0,他引:2  
以3头安装永久性瘤胃瘘管的荷斯坦产奶牛为试验动物。用尼龙袋法研究测定了奶牛常用饲料蛋白质在瘤胃内的动态降解规律及其有效降解率。结果表明:常用蛋白质饲料中葵花粕与豆粕粗蛋白(CP)的有效降解率较高。酒糟CP降解率最低。籽实与糠麸类饲料中麸皮CP有效降解率最高,稻壳最低。常用粗饲料中苜蓿草与苜蓿草块的CP有效降解率均高于其他粗饲料,玉米秸秆的CP有效降解率最低。不同饲料蛋白质瘤胃有效降解率与蛋白质慢速降解组分呈极显著中度正相关(r=0.5013,P〈0.01),与蛋白质快速降解组分呈弱的正相关(相关性趋于显著r=0.3675。P=0.06),与非降解组分呈极显著高度负相关(r=-0.7153,P〈0.01)。  相似文献   

11.
Two experiments, using Angus x Hereford spring-calving beef cows in mid- or late lactation nursing Simmental-sired calves, were conducted to evaluate the relative value of a corn gluten meal-blood meal mixture (CGM-BM; 50% of supplemental protein from each source). In Exp. 1 (78 d), cows in late lactation were assigned to one of three treatments: control at 8.2% CP (C), soybean meal at 10.4% CP (SBM), or CGM-BM at 10.3% CP. Diets were calculated to be isocaloric at 55% TDN. In Exp. 2 (65 d), cows in mid-lactation were assigned to four treatments: urea, SBM, low CGM-BM (LM), and high CGM-BM (HM). Diets in Exp. 2 were isonitrogenous (9.5% CP) and isocaloric (55% TDN). Diets in both experiments were based on ammoniated wheat straw and corn silage. Weight gains of cows and cow-calf pairs were greater (P less than .06) when protein was supplemented in Exp. 1. Gains were lower for cows fed urea (P less than .03) in Exp. 2 but were similar when cows were supplemented with SBM vs either the low or the high level of CGM-BM. Performance of calves did not differ among dietary treatments.  相似文献   

12.
本试验旨在研究马铃薯淀粉渣和玉米秸秆混合青贮料对肉牛瘤胃内环境及血清生化指标的影响.选择4头平均体重(455.00±19.50)kg的健康秦川杂交肉牛,随机分配到4×4拉丁方试验设计中.4组分别为:1)对照组,40%精料+60%玉米秸秆黄贮料;2)S25组,40%精料+45%玉米秸秆黄贮料+15%马铃薯淀粉渣和玉米秸秆混合青贮料;3)S50组,40%精料+30%玉米秸秆黄贮料+30%马铃薯淀粉渣和玉米秸秆混合青贮料;4)S75组,40%精料+15%玉米秸秆黄贮料+45%马铃薯淀粉渣和玉米秸秆混合青贮料.结果表明:各组肉牛平均日增重、干物质采食量和蛋白质摄入量均差异不显著(P>0.05).S25、S50和S75组肉牛瘤胃液氨态氮浓度均高于对照组(P>0.05),分别提高了58.96%、36.35%、26.17%.各组乙酸、丙酸、丁酸、戊酸、总挥发性脂肪酸浓度和乙酸、丙酸、丁酸、戊酸比例及乙酸/丙酸、(乙酸+丁酸)/丙酸均无显著差异(P>0.05).各组间血清总蛋白、尿素氮和葡萄糖含量均无显著差异(P>0.05).由此可知,马铃薯淀粉渣和玉米秸秆混合青贮料替代部分玉米秸秆黄贮料能提高肉牛瘤胃液氨态氮浓度,对瘤胃液挥发性脂肪酸含量和血清生化指标无影响.马铃薯淀粉渣和玉米秸秆混合青贮料可以替代肉牛饲粮中75%的玉米秸秆黄贮料.  相似文献   

13.
酵母菌发酵玉米秸秆试验研究   总被引:2,自引:0,他引:2  
室温条件下用酵母菌对玉米秸秆进行发酵试验。发酵完成后,测定其粗蛋白(CP)、粗脂肪(EE)、粗纤维(CF)和可溶性糖(WSC)含量并进行比较。研究表明,原料配方麸皮∶酵母∶秸秆=2∶2∶100发酵效果好,发酵后CP提高1.93%,EE提高0.51%,且差异极显著(P<0.01);发酵10~15 d,CP可达到6.49%~6.61%,EE为0.82%~0.95%,与其他组差异极显著(P<0.01);切短长度对发酵效果有明显影响,秸秆粉碎后发酵效果显著,但会增加发酵成本;水分含量应掌握在60%~70%,可以取得较好的发酵效果;酵母菌发酵对玉米秸秆粗纤维作用甚微。  相似文献   

14.
为了探索鹅对青贮玉米秸秆利用的可行性与效果,本试验选取24月龄的健康五龙鹅30只,随机分为5组,每组6个重复。各试验组日粮青贮玉米秸秆的比例分别为24.30%、34.60%、42.60%、49.10%、53.60%,采用全收粪法进行代谢试验,检测饲料与粪便中的各种营养成分,确定其消化率,并观察肠道微生物菌群变化。试验结果表明:在代谢能(ME)和粗蛋白质(CP)摄入量基本一致的条件下,随着青贮玉米秸秆添加水平的提高,粗纤维(CF)的消化率为18.16%~48.28%,中性洗涤纤维(NDF)42.68%~58.51%,酸性洗涤纤维(ADF)28.56%~49.32%;氮沉积量、净蛋白质利用率(NPU)各组间差异显著(P<0.05);各组粪中的氨态氮(NH3-N)浓度呈下降趋势;除甘氨酸表观消化率偏低但组间差异极显著(P<0.01)外,其他各种氨基酸表观消化率(AAAD)均较高(77.30%~93.10%)。Ca表观消化率随青贮玉米秸秆添加比例递增呈显著递减趋势(P<0.05);P表观消化率在添加53.60%青贮玉米秸秆时显著低于其他各组(P<0.05)。碱性磷酸酶(AKP)活性与CF、NDF和ADF的消化率呈显著负相关(P<0.05),与Ca的表观消化率呈极显著正相关(P<0.01);谷草转氨酶(GOT)、谷丙转氨酶(GPT)酶活与CF呈显著负相关(P<0.05),与Ca的表观消化率呈显著正相关(P<0.05)。青贮秸秆添加量在24.30%~49.10%时,粪便中双歧杆菌、乳酸杆菌数量均随秸杆添加水平的升高而增多(P<0.05);大肠杆菌数量总体呈下降趋势。试验说明鹅能较好的利用青贮玉米秸秆中的营养物质,利用青贮玉米秸秆养鹅是可行的。  相似文献   

15.
旨在研究不同处理方法对稻草感官品质及营养成分的影响。选用优质干稻草,分别用氢氧化钠、尿素、碳酸氢铵、纤维素酶处理,并取相同重量的原稻草,不进行处理作为对照组。结果表明,处理20 d和40 d后,各组稻草感官品质无明显差异(P〉0.05),氢氧化钠组稻草呈浅黄色,草香味,质地柔软;尿素组稻草呈金黄色,氨味(放氨后有糊香味),质地柔软;碳酸氢铵组稻草呈浅黄色,氨味,质地柔软;纤维素酶组稻草呈浅黄色,酸香味,质地柔软。稻草处理20 d后,与对照组相比,各处理组CP、EE、Ash、Ca、TP无显著性差异(P〉0.05);稻草处理40 d后,与对照组相比,尿素组CP提高了8.86%(P〈0.05),尿素组和碳酸氢铵组中CP显著高于其他组,其他养分各组间无显著差异(P〉0.05)。稻草经氢氧化钠、尿素、碳酸氢铵、纤维素酶等处理后,可以不同程度地改变稻草的物理特性和营养价值。从感官品质、主要营养成分以及成本来看,尿素和碳酸氢铵处理较经济实用,有利于在生产中推广;而酶处理目前由于成本较高,还有待于进一步研究。  相似文献   

16.
路桂聪  许辉  玉永雄  蒋曹德 《草业科学》2022,1(1):2191-2199
本研究采用四因素三水平正交设计试验,探讨了玉米粉(A) (0、3%、6%)、尿素(B) (0、0.3%、0.6%)、乳酸菌(C) (0、5、10 g·t?1)、密度(D) (700、800、900 kg·m?3)对高水分杂交狼尾草(Pennisetum americanum × P. purpureum)青贮品质及营养价值的影响,筛选出最佳的青贮密度以及玉米粉、乳酸菌和尿素添加量,以提高杂交狼尾草的青贮品质。结果显示:1) 6个处理组感官评定综合评分9~15分,等级为二级以上。2)随着玉米粉剂量的增加,极显著地提高了青贮料粗蛋白(crude protein, CP)含量和相对饲用价值(relative feeding value, RFV) (P < 0.01),极显著地降低了中性洗涤纤维(neutral detergent fiber, NDF)、酸性洗涤纤维(acid detergent fiber, ADF)、粗灰分(crude ash, Ash)含量、pH以及氨态氮的水平(P < 0.01)。3)尿素极显著地提高了青贮料中CP含量与RFV (P < 0.01),显著地降低了NDF和ADF含量(P < 0.05),当尿素的添加量为0.6%时,CP含量提高了7.05%,NDF和ADF含量分别降低了1.38%和1.45%。4)当乳酸菌剂添加量和青贮密度分别为5 g·t?1和700 kg·m?3时,RFV最高,NDF含量最低,干物质(dry matter, DM)含量介于其他处理之间。上述结果表明,3种添加物均能显著改善杂交狼尾草青贮发酵效果,其主次影响顺序分别为玉米粉 > 尿素 > 乳酸菌剂,且密度为700 kg·m?3时效果最好。最优配比为6%的玉米粉、0.6%的尿素、5 g·t?1的乳酸菌、700 kg·m?3的密度。  相似文献   

17.
The study was conducted to examine the chemical composition of urea–molasses treated wheat straw (WS) fermented with cattle manure (CM) and its feeding value for growing buffalo male calves. Wheat straw treated with varying levels of urea (0%, 2% and 4%) and molasses (2% and 4%) was ensiled with 30% cattle manure (on dry matter basis) for different fermentation periods (20, 30 and 40 days). Fermented wheat straw (FWS) after each fermentation period was analyzed for pH, dry matter (DM), crude protein (CP), true protein (TP), ammonia nitrogen (NH3-N), acid detergent fiber (ADF) and neutral detergent fiber (NDF). Maximum pH, DM, CP, TP and NH3-N and minimum NDF contents were observed with 4% urea. The 4% molasses level increased the CP, TP and NH3-N contents of FWS, but pH, DM and NDF remained unchanged after 40 days of fermentation. The 4% urea × 4% molasses interaction resulted in maximum DM, CP, TP, NH3-N after 40 days of fermentation period and this combination was used for large scale production of FWS to evaluate its feeding value for calves. Four isonitrogen and isocaloric diets were formulated. The control FWS 0 diet contained no FWS while in FWS 15, FWS 25 and FWS 35 diets concentrate was replaced with 15%, 25% and 35% FWS, respectively. The diets were randomly allotted to four groups of 28 calves 9–12 months of age, seven in each group, in a randomized complete block design to examine the nutrient intake, digestibility, nitrogen balance and weight gain. An increased DM, organic matter (OM), CP and NDF intakes were observed in calves fed FWS diets compared to those fed FWS 0 diet. Nitrogen retention increased significantly with increasing the level of FWS. The DM, OM, CP and NDF apparent digestibilities were non-significant in calves fed different levels of FWS. A linear increase in weight gain was noticed in calves fed diets containing increasing level of FWS.  相似文献   

18.
氮肥追施量对玉米秸秆营养价值的影响   总被引:2,自引:0,他引:2  
用目前生产中普遍种植的青饲玉米品种白马牙(Zea mays L.)的秸秆为试验材料,通过化学成分分析、活体外消化率测定、活体外发酵产气量测定和羊的饲养试验,研究了氮肥施肥量(尿素0、150、300、450kg/ha)对玉米秸秆营养价值的影响。结果表明:随着追施尿素量的增加,氨基酸总量、非必需氨基酸总量和粗蛋白、真蛋白、各种必需氨基酸、Ca含量呈直线规律提高(P〈0.001),而粗脂肪和ADF含量则均不受影响(P〉0.05);追施尿素低于300kg/ha时,总糖含量不受尿素量的影响,尿素量高于300kg/ha时,总糖含量则随尿素量的提高而减少。追施尿素能够提高(P〈0.001)玉米秸秆活体外DMD、CPD、NDFD和ADFD,并且,各项消化率指标随尿素量的提高也呈直线规律提高(P〈0.001),但尿素量超过300kg/ha时,这种作用效果不再提高。用不同尿素追施量的青贮玉米秸秆饲喂大尾寒羊羔羊,羔羊增重、饲料转化效率和经济效益随施肥量的提高而提高,其中,以尿素量为300kg/ha时效果最好。可见,追施氮肥不仅能够改变玉米秸秆的化学成分含量.而且能够提高玉米秸秆的营养价值。  相似文献   

19.
The objective of this study was to examine the effects of pelleted total mixed rations (PTMR) containing two crude protein (CP) levels and N sources with different ruminal degradability on milk yield and composition of lactating ewes. The experiment, which lasted 14 weeks, was conducted during the spring and summer of 2007 and used 80 multiparous Comisana ewes in mid-lactation, reared in permanent stabling. A 2 × 2 factorial design was used, with ewes receiving two levels of CP (low 15.5% CP and high 17.5% CP) and two type of N sources with different rumen degradable protein (low and high) for each dietary treatment: (1) high-degradable protein diet (17.5% CP) composed by soybean meal, sunflower meal and urea (HPHD), (2) low-degradable protein diet (17.5% CP) included only corn gluten meal (HPLD), (3) high-degradable protein diet (15.5% CP) composed by soybean meal, sunflower meal and urea (LPHD), and (4) low-degradable protein diet (15.5% CP) included only corn gluten meal (LPLD). In order to evaluate in vivo digestibility of PTMRs, four adult rams were placed in metabolic cages and their individual faeces and urine were collected. In the performance trial, ewe milk yield was recorded daily and Individual milk samples were analysed weekly for milk composition and to determine milk renneting parameters. The 17.5% CP diets led to better nutrient apparent digestibility coefficients and had positive effects on milk production than the 15.5% CP diets. Similar results were obtained for corn gluten meal diets, compared to diets containing soybean meal, sunflower meal and urea. Data showed that corn gluten meal diets have had a positive effects on milk fat (P < 0.05), but not on milk protein, lactose and renneting parameters. All ewes gained weight during the experimental period, but the body weight change was not significant among treatments. Our findings indicate that an increase in rumen undegradable protein (RUP) content does not negatively affect nutrient digestibility of sheep rations and milk yield and composition.  相似文献   

20.
Five steers (491 +/- 21 kg BW) were used in an incomplete 5 x 4 Latin square with four 24-d periods to determine the influence of supplemental non-protein N (NPN) source and supplementation frequency (SF) on nutrient intake and site of digestion in steers consuming low-quality grass straw (4% CP). Treatments (TRT) included an unsupplemented control and a urea- or biuret-containing supplement placed directly into the rumen daily (D) or every other day (2D) at 0700. The NPN treatments were formulated to provide 90% of the estimated degradable intake protein requirement. Daily TRT were supplemented CP at 0.04% of BW/d, whereas the 2D TRT were supplemented at 0.08% of BW every other day. Therefore, all supplemented TRT received the same quantity of supplemental CP over a 2-d period. Forage OM intake was not affected (P > 0.05) by NPN supplementation, NPN source, or SF; however, total OM and N intake were increased (P < 0.01) with CP supplementation. Duodenal flow of N was greater (P = 0.04) with CP supplementation compared with the control. In addition, duodenal bacterial N flow was increased with CP supplementation (P = 0.04) and for biuret compared with urea (P < 0.01). Bacterial efficiency (g bacterial N/kg OM truly digested in the rumen) was greater (P = 0.05) for biuret than for urea. Apparent total-tract N digestibility was increased with NPN supplementation (P < 0.01) but not affected by NPN source or SF. These results suggest that urea or biuret can be used effectively as a supplemental N source by steers consuming low-quality forage.  相似文献   

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