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1.
本试验旨在研究饲粮中添加籽粒苋青贮和干草对泌乳奶牛瘤胃发酵、营养物质表观消化率、血液指标和生产性能的影响。选取产奶量、胎次和泌乳天数等相近的健康荷斯坦奶牛45头,随机分成3组,每组15头牛。对照组粗饲料包括全株玉米青贮、羊草和苜蓿干草,试验Ⅰ组粗饲料使用籽粒苋青贮替代30%玉米青贮,试验Ⅱ组粗饲料使用籽粒苋干草替代30%苜蓿干草。3组饲粮营养水平接近。预试期10 d,正试期60 d。结果表明:1)与对照组相比,试验Ⅰ组能显著提高粗蛋白质(CP)表观消化率、瘤胃液氨态氮(NH_3-N)和血液总氨基酸(T-AA)的含量(P0.05),对其他营养物质表观消化率、血液指标和乳成分影响不显著(P0.05)。2)与对照组相比,试验Ⅱ组的血液T-AA含量显著高于对照组(P0.05),对其他血液指标、瘤胃发酵指标、营养物质表观消化率和乳成分均无显著影响(P0.05)。综上所述,饲粮中添加适量的籽粒苋不会影响奶牛的生产性能,同时会提高牧场经济效益。  相似文献   

2.
Eight lactating Holstein cows were divided into two groups ( n  = 4) and used in a double reversal trial with three periods of 14 days each, to evaluate diets containing propylene glycol (PG) and ruminally undegradable protein (RUP) blend on milk yield and composition, ruminal fermentation and blood metabolism. The control diet contained 20% chopped Sudangrass hay, 20% cubed alfalfa hay, 12% corn silage, and 48% of the respective concentrate mixtures (dry matter basis). The experimental diet (PG + RUP) partially replaced the concentrate mixture from the control diet with 1.4% PG and 2.1% RUP. Both diets contained about 16% crude protein and 71% total digestible nutrients. Dry matter intake was similar between the two diets. Daily production of milk, milk lactose and milk solids-not-fat increased by 9.0%, 11.3% and 9.3%, respectively ( P  < 0.1), for cows fed diets with PG + RUP; milk composition was unchanged. Although the concentration of ruminal total volatile fatty acids was unchanged, the proportion of propionic acid increased, and the proportion of acetic acid decreased with PG + RUP. The concentration of ruminal ammonia nitrogen and number of ciliate protozoa was not significantly affected by PG + RUP. The concentration of glucose in blood plasma increased, the concentration of urea nitrogen was unaffected, and the concentration of some essential free amino acids decreased with PG + RUP. It is suggested that these changes might be caused predominantly by PG, and the addition of PG may exert a favorable effect on milk production through increased metabolism.  相似文献   

3.
紫花苜蓿和裸燕麦混贮发酵品质和营养成分分析   总被引:3,自引:0,他引:3  
以新鲜及晾晒后的紫花苜蓿和裸燕麦为原料,分别设计紫花苜蓿单贮、裸燕麦单贮、裸燕麦∶紫花苜蓿=1∶1、裸燕麦∶紫花苜蓿=2∶1及裸燕麦∶紫花苜蓿=1∶2混贮等5个处理,青贮60 d后,对其感官评分、发酵品质和营养成分等进行分析。结果表明,鲜贮苜蓿在感官评定、V-Score及Kaiser评价体系中表现一般,而晾晒及混合青贮各处理组均能不同程度提高青贮评分。晾晒和混合青贮对发酵品质产生影响,两者显著或极显著降低pH值、 PA(丙酸)、AA(乙酸)、BA(丁酸)和AN/TN(氨态氮/总氮)含量(P<0.01或P<0.05),显著或极显著升高LA(乳酸)含量(P<0.01或P<0.05),其中以裸燕麦∶紫花苜蓿=2∶1降低或升高最明显。晾晒对青贮饲料的干物质、可溶性碳水化合物及粗灰分含量具有显著或极显著影响(P<0.05或P<0.01),对其他养分含量影响不大(P>0.05)。混合比例对青贮饲料的所有发酵项目均有极显著影响(P<0.01),对粗蛋白质、可溶性碳水化合物及中性洗涤纤维含量具有显著或极显著影响(P<0.05或P<0.01),对其他养分指标影响不显著(P>0.05)。晾晒和混合青贮的交互作用可显著提高青贮饲料的发酵品质,但对养分含量影响不明显。因此,从青贮后感官评价、发酵品质及养分含量来看,紫花苜蓿和裸燕麦混合青贮品质优于单独青贮,且晾晒相对于鲜贮更易于青贮,而无论晾晒和鲜贮,当裸燕麦∶紫花苜蓿=2∶1时,青贮品质均优于其他各组。  相似文献   

4.
为提高紫花苜蓿青贮饲料的发酵品质,抑制不饱和脂肪酸的损失,以无添加剂为对照,研究了添加剂:苯甲酸钠、酪蛋白酸钠、十六烷酸、糖蜜和丙酸,对紫花苜蓿青贮饲料发酵品质和脂肪酸的影响。青贮65 d后开窖,检测发酵品质指标和各种脂肪酸的含量。结果表明:对照组的pH低于4.50,乳酸含量达到54.25 g·kg-1 DM,丁酸含量低于5.00 g·kg-1 DM,弗氏评分为64.33,具有良好的发酵品质。与青贮前相比,青贮后苜蓿青贮饲料中的亚油酸(C18:2n6)和亚麻酸(C18:3n3)的含量显著增加(P<0.05)。青贮后,与对照组相比,十六烷酸和酪蛋白酸钠添加组分别不显著(P>0.05)和显著地(P<0.05)降低了乳酸含量;酪蛋白酸钠添加组增加了丁酸含量(P<0.05);二者的弗氏评分低于50.00,降低了发酵品质。与此相反,苯甲酸钠、丙酸和糖蜜添加组不同程度地增加了乳酸含量,降低了pH,减少了氨态氮和酸性洗涤纤维的含量,弗氏评分分别为70.33、74.33和67.67,进一步提高了青贮发酵品质。与对照相比,苯甲酸钠和丙酸添加组不同程度地增加了C18:2n6或C18:3n3的含量,而糖蜜添加组降低了C18:2n6和C18:3n3的含量(P<0.05)。综上所述,丙酸和苯甲酸钠适宜于作为青贮添加剂生产优质紫花苜蓿青贮饲料。  相似文献   

5.
Nine multiparous Holstein cows were used in a replicated 3 × 3 Latin square design to determine the effects of substituting corn grain with brown rice (BR) grain in total mixed ration (TMR) silage on milk yield, ruminal fermentation and nitrogen (N) balance. The TMR silages were made from the ensiling of TMR containing (dry matter basis) 50.1% forage in rice silage and corn silage combination, and 49.9% concentrate. The grain portion of the diets contained 31.2% steam‐flaked corn, 31.2% steam‐flaked BR or an equal mixture of corn and BR. Dietary treatments did not affect dry matter intake, milk yield and milk fat, protein and lactose yields. The ruminal pH and total volatile fatty acid concentrations were not affected by dietary treatment. The urinary N excretion decreased linearly (P < 0.01) in response to increased levels of BR, with no dietary effect on N intake, N secretion in milk and fecal N excretion. Our results indicate that steam‐flaked BR is a suitable replacement for steam‐flaked corn in dairy cow diets, and that it can be included in rations to a level of at least 31.2% of dry matter without adverse effects on milk production, when cows were fed rice silage and corn silage‐based diets.  相似文献   

6.
试验旨在探讨苜蓿青贮料替代不同比例苜蓿青干草对奶牛生产性能、乳品质、营养物质表观消化率、血液生化指标及经济效益的影响。选取体重、产奶量、胎次相近的健康泌乳中期中高产中国荷斯坦奶牛15头,随机分为3组,每组5个重复,每个重复1头牛。对照组饲喂4.0 kg苜蓿青干草,试验A、B组分别用4.4,8.8 kg苜蓿青贮料代替2.0和4.0 kg等干物质的苜蓿青干草,正试期64 d。结果表明,1)各组间干物质采食量差异不显著(P>0.05),B组产奶量显著低于对照组(P<0.05),A组与对照组、B组间差异不显著(P>0.05); 2)用50%,100%的苜蓿青贮料替代等干物质的苜蓿青干草,其乳蛋白、乳脂率、乳糖均有所改善,但只有B组的乳脂率显著高于对照组(P<0.05),其余指标各组间差异均不显著(P>0.05);3)A、B组与对照组的中性洗涤纤维表观消化率、钙表观消化率无显著性差异(P>0.05),A、B组间粗蛋白和磷表观消化率差异不显著(P>0.05),但是粗蛋白表观消化率均显著低于对照组、磷表观消化率均显著高于对照组(P<0.05);4)苜蓿青贮料替代苜蓿青干草其血清总蛋白、白蛋白、血尿素氮、血糖、二氧化碳结合力等指标没有显著性改变(P>0.05);5)试验A、B组经济效益均有所增加,其中A组的净增收益最高,为0.61元/(头·d)。综上,用4.4 kg苜蓿青贮料代替2.0 kg苜蓿青干草对中高产奶牛是适宜的,能提高其生产性能,改善乳品质,增加收益。  相似文献   

7.
Four wethers were used in a 4 × 4 Latin square to study the feed intake, apparent digestibility, nitrogen balance and ruminal fermentation characteristics when fed total mixed ration (TMR) silages which included wet barley tea grounds (WBTG). The TMR silages were prepared using compound feed including wet brewers' grains (WBG), corn, oat hay, alfalfa hay, dried beet pulp, salt and vitamin-mineral supplement in a ratio of 30.7:15:8:24:10:12:0.15:0.15, respectively, on a dry matter (DM) basis. The WBTG and soybean meal mixture (7:3 on DM basis) were substituted for WBG at ratio of 0% (Control), 5% (LTG), 10% (MTG), and 15% (HTG) on DM of TMR. WBTG addition to the TMR silages increased lactic acid concentration, decreased pH, acetic acid and ammonia-N ( P  < 0.001). Feed intakes and digestibilities for LTG and MTG (except ether extract (EE) digestibility) treatments were not different from the control ( P  > 0.05). However, EE and neutral detergent fiber (NDF) intake, crude protein, EE and NDF digestibility was lower, but the DM and gross energy digestibility was higher for the HTG treatment compared to control ( P  < 0.01). With progressive increases in WBTG concentrations, nitrogen intake, fecal nitrogen and retention nitrogen did not differ, but the urinary nitrogen for MTG and HTG treatments were lower than that of the control ( P  = 0.001). The ruminal total volatile fatty acid concentration and the molar ratios of propionate and butyrate were higher, but the acetate, ratio of acetate to propionate and ammonia-N content were lower for the HTG treatment compared with the control ( P  < 0.05). Therefore, the possible proportion of replacing WBG with WBTG for TMR silage can be 10% or less of the diet DM.  相似文献   

8.
以分别晾晒4h、8h、12h和24h后调制的紫花苜蓿青贮为主要原料,添加8%豆粕和22%玉米粉后进行二次青贮,室温贮藏45d后取样分析.结果表明:添加豆粕和玉米粉能显著改善晾晒4h、8h后青贮的紫花苜蓿青贮饲料再次青贮的发酵品质(P<0.05),而对于晾晒12h、24h后青贮的紫花苜蓿青贮饲料,添加组的发酵品质普遍较差;第二次青贮后,氨态氮占总氮的百分含量随着晾晒时间增加而显著降低(P<0.05).晾晒4h、8h后青贮的紫花苜蓿青贮饲料再添加玉米粉和豆粕调制混合发酵饲料是可行的,其中以晾晒4h后青贮的紫花苜蓿青贮饲料为原料效果最佳.  相似文献   

9.
The effects of proteolysis on digestion and animal performance were studied using heat to inhibit proteolysis at ensiling. Alfalfa (Medicago sativa) was ensiled either after wilting for 24 h (control; C) or after heating (100 degrees C) in a crop dehydrator for 2 min (heated; H). In Exp. 1, eight wethers, cannulated in the rumen and duodenum, were given the silages to determine the effects of heat treatment of alfalfa on the digestion of silage. In Exp. 2, growing lambs had ad libitum access to the silages to determine the effects of heat treatment on intake, animal performance and body composition. Heat treatment inhibited protease activity; protein N accounted for 33.5 and 61.3% and ammonia N 15.5 and 5.1% of total N in C and H silages, respectively. Heat treatment reduced mean post-feeding ruminal ammonia N concentration (P less than .05), ruminal pH (P less than .05) and the acetate: propionate ratio (P less than .001) in ruminal fluid. Heat treatment increased duodenal flow of non-ammonia N (P less than .05) and amino acids (P less than .05), the amount of N absorbed (P less than .05) in the small plus large intestine and also increased the efficiency of microbial protein synthesis (P less than .05). In Exp. 2, although intake and gain were higher (P less than .001) for H-fed than for C-fed lambs, there were no differences (P greater than .05) in empty body composition. The results indicated that inhibition of proteolysis by heat treatment at ensiling can increase utilization of silage N within the rumen, increase voluntary intake and result in a higher rate of gain by lambs fed alfalfa silage.  相似文献   

10.
This study was conducted to evaluate silage fermentation and protein degradation of alfalfa prepared with corn or sweet sorghum (SS) at different mixing ratios. The chemical composition, ensiling characteristics, and protein degradation of alfalfa prepared with and without corn or SS at mixing ratios of 7:3, 1:1, and 3:7 on a fresh matter (FM) basis were studied. The alfalfa had the highest crude protein (CP) content and lactate buffering capacity (LBC), but lower water‐soluble carbohydrate (WSC) content than corn and SS. After 60 days of ensiling, the corn and SS silages had good quality, with lower pH and ammonia‐N content, and higher dry matter (DM) content than the alfalfa silages. In the alfalfa and corn mixture silages, the DM contents linearly increased with an increase in the proportion of corn, while the pH, non‐protein N (NPN), ammonia‐N, and peptide‐N contents linearly decreased. In the alfalfa and SS mixture silages, the DM and NPN contents linearly increased with an increase in the proportion of SS, while the pH, lactic acid, and ammonia‐N contents linearly decreased. This study suggests that alfalfa silage prepared with corn has more positive effect on fermentation quality and inhibiting protein degradation than addition of SS.  相似文献   

11.
苜蓿与玉米秸秆混贮研究   总被引:9,自引:3,他引:6  
孙小龙  周禾  李平  玉柱 《草业学报》2009,18(5):86-92
以二茬苜蓿和玉米秸秆为原料,研究乳酸菌制剂、纤维素分解酶制剂、绿汁发酵液、乳酸菌制剂和纤维素分解酶及绿汁发酵液和纤维素分解酶的复合添加对苜蓿与玉米秸秆混合青贮品质的影响。结果表明,苜蓿与玉米秸混贮可以提高青贮保存性能;苜蓿与玉米秸各混贮比例处理均获得良好效果;在苜蓿、玉米秸混贮中使用添加剂可以进一步提高青贮品质;各处理均显著降低了丁酸含量(P<0.05),同时pH值均小于或接近于4.2,与对照组相比差异显著(P<0.05); 乳酸菌制剂+纤维素分解酶处理组效果最好,在3个混贮组中,该处理的V-Score青贮质量评价均得到了良好的等级;添加纤维素分解酶使NDF含量显著下降,平均下降了3.77%(P<0.05);7∶3混贮组中添加纤维素酶制剂显著提高了青贮饲料的CP含量(P<0.05),提高了6.0%。  相似文献   

12.
张欢  牟怡晓  张桂杰 《草业学报》2022,31(4):136-144
本试验旨在研究宁夏地区枸杞副产物对苜蓿青贮品质及微生物多样性的影响,为提高苜蓿青贮品质和寻找优质饲料添加剂提供科学依据。紫花苜蓿分别与0(CK)、40(T1)、60(T2)、80(T3) g·kg-1枸杞副产物混合青贮,发酵60 d后测定青贮营养成分、发酵品质及微生物多样性。结果表明:枸杞副产物处理组相比对照组,显著降低了酸性洗涤纤维含量(P<0.01),显著提高了多糖含量(P<0.01);对照组pH值及氨态氮/总氮分别为4.91、8.58%,苜蓿青贮中pH、氨态氮及乙酸含量随枸杞副产物比例增加而显著降低(P<0.01),乳酸含量及乳酸乙酸比显著增加(P<0.01);此外,枸杞副产物提高了青贮有氧稳定性,其中T1及T2处理组有氧稳定性较高。苜蓿青贮优势菌属主要为乳杆菌属、魏斯氏菌属和片球菌属,枸杞副产物降低了苜蓿青贮中乳杆菌属的相对丰度,增加了魏斯氏菌属及片球菌属的相对丰度。综上所述,枸杞副产物可改善苜蓿青贮发酵品质,提高有氧稳定性,改变微生物群落结构,且枸杞副产物添加量为60 g·kg-1的处理组青贮发酵效果优于其他添加量。  相似文献   

13.
Effects of different chemical additives on peptide composition in ensiled alfalfa (Medicago sativa L.) were investigated by using gel filtration and determination of N characteristics. The alfalfa silages were prepared untreated (control) or with formic acid, formaldehyde or tannic acid as additives at ensiling. All additives reduced non‐protein N (NPN), ammonia nitrogen (NH3‐N) and amino acid N (AA‐N) in the ensiled forage, and the most effective reduction of NPN and AA‐N was observed in the formaldehyde‐treated silages. Peptides in the control silage were mainly dipeptides to peptides with five amino acid residues. Most peptides in the formic acid‐treated silage contained 4–12 amino acid residues. Although most peptides in the formaldehyde‐treated silages contained 4–6 amino acid residues, there was a considerable proportion of peptides with 7–11 amino acid residues. Tannic acid had little effect on peptide size of ensiled alfalfa extract in which most peptides contained 5–6 amino acid residues. Peptide size in formic acid‐treated alfalfa silage was greater than that in the other treatments. Addition of formic acid and formaldehyde not only increased the peptide concentration in alfalfa silage, but enlarged the peptide size.  相似文献   

14.
To investigate the effects of inoculants and environmental temperature on fermentation quality and bacterial diversity of alfalfa silage, first‐cut alfalfa was ensiled with or without two screened lactic acid bacteria (LAB) strains, Lactobacillus plantarum, LP, and Lactobacillus casei, LC. Each treatment was divided into three parts and stored at 20°C, 30°C, 40°C, respectively. After 60 days ensiling, fermentation characteristics were measured and bacterial diversity was investigated by 16S ribosomal RNA gene sequencing using Illumina MiSeq platform. LP and LC decreased pH, coliform bacteria counts and increased lactic acid content at 20°C, and the two strains decreased pH, ammonia‐N concentration, coliform bacteria counts at 30°C. When the environmental temperature was 40°C, silage treated with LC showed lower LAB and coliform bacteria counts and higher lactic acid content than the untreated and LP treated silages. Butyric acid mainly appeared in silages stored at 40°C. The relative abundance of Lactobacillus in alfalfa silages stored at 20°C and 30°C was highest and increased after LP and LC were added. Garciella was another dominant genus in silages stored at 40°C. In conclusion, LP and LC improved fermentation quality of alfalfa silage by increasing Lactobacillus proportions at 20°C and 30°C; ensiling alfalfa at 40°C was difficult because of Garciella.  相似文献   

15.
试验在青稞秸秆与多年生黑麦草以6∶4混合的基础上,添加3%,4%和5%的糖蜜,旨在进一步改善混合青贮发酵品质和营养价值,为西藏地区青稞秸秆青贮利用提供理论依据。结果显示,青贮前14天,糖蜜添加组乳酸含量快速增加,pH值迅速下降。对照组pH值未能降至4.2以下,而糖蜜添加组均在4.0左右,乳酸、水溶性碳水化合物含量和乳酸/乙酸显著高于(P<0.05)对照组,氨态氮/总氮均低于对照组,且添加3%糖蜜已达到优质青贮饲料标准。青贮第60天糖蜜添加组有较高的粗蛋白含量,较低的中性洗涤纤维和酸性洗涤纤维含量,各组体外降解率均高于青贮材料。综合考虑,在青稞秸秆和黑麦草以6∶4混合的基础上添加3%的糖蜜可获得优质青贮饲料。  相似文献   

16.
不同添加剂对陇东紫花苜蓿青贮品质的影响   总被引:1,自引:0,他引:1  
生物添加剂在促进牧草青贮发酵过程中有益菌和酶的活性、提高消化率和改善发酵品质等方面发挥着重要作用。本研究以初花期刈割的第1茬陇东紫花苜蓿(Medicago sativa)为原料,分析不同添加剂(甲酸、蔗糖、EM菌液和纤维素酶)对青贮发酵品质的影响。结果表明,4种添加剂处理组苜蓿青贮饲料感官评定得分均高于无添加剂对照组,pH、乙酸和氨态氮(NH3-N)/总氮(TN)含量均显著(P<0.05)低于对照组,乳酸含量均显著(P<0.05)高于对照组,且未检测到丁酸和丙酸。4种添加剂处理组的粗蛋白质含量均显著(P<0.05)高于对照组,酸性洗涤纤维含量均显著(P<0.05)低于对照组。蔗糖组、EM菌液组和纤维素酶组的中性洗涤纤维含量均显著(P<0.05)低于甲酸组和对照组。粗灰分含量各组间无显著差异(P>0.05)。4种添加剂处理组的有氧稳定性均显著(P<0.05)高于对照组。上述结果说明,4种添加剂都可以提高陇东紫花苜蓿青贮的发酵品质、营养价值,延长有氧稳定性。但以纤维素酶组pH、乙酸和NH3-N/TN含量最低,乳酸含量最高,青贮发酵品质最佳,建议在生产实践中大量推广应用。  相似文献   

17.
As a forage source for total mixed ration (TMR) silage production, locally produced crop silage is now used in addition to imported hay. This type of TMR ensiling is regarded as a two‐step fermentation process; hence, a survey was carried out to determine whether the bacteria in crop silage affect the subsequent TMR ensiling. Fermentation product contents and bacterial community were determined for TMR silage and its ingredient silages collected in August, October and November. August product contained corn, sorghum and Italian ryegrass silages, October product had wheat silage exclusively and November product did not include any crop silages. Acetic acid, lactic acid, 2,3‐butanediol and ethanol were predominant fermentation products in corn, sorghum, Italian ryegrass and wheat silages, respectively. Robust lactic acid fermentation was seen in TMR silage, even if acetate‐type and alcohol‐type silages were mixed as ingredients. The finding that bacterial community of the TMR silage appeared unrelated to those of ingredient silage supported this. Silages of various fermentation types can therefore be formulated without interfering with lactate‐type fermentation in TMR silage.  相似文献   

18.
为评价添加酶、乳酸菌制剂和酶+乳酸菌制剂对苇状羊茅与箭筈豌豆(7∶3)混合青贮发酵品质的影响,试验设对照组(C)、酶制剂(E)、乳酸菌制剂(LAB)和酶+乳酸菌制剂(E+LAB)4个处理,3个重复,青贮后第7,24,60天开窖取样,测定青贮饲料发酵品质。结果表明,与对照组相比,添加酶或乳酸菌制剂能有效地改善混合青贮发酵品质,组合添加进一步提高了乳酸含量和降低了pH值。与对照组和单独添加乳酸菌组相比,在整个青贮过程中无论是酶单独添加还是组合添加都显示较高的乙酸和总挥发性脂肪酸含量,最高的水溶性碳水化合物含量和最低的氨态氮/总氮。这说明酶和乳酸菌制剂组合添加对改善青贮发酵品质有叠加效应。综上所述,酶和乳酸菌制剂组合添加能更好的改善苇状羊茅和箭筈豌豆混合青贮的发酵品质。  相似文献   

19.
为探讨不同水平乙酸对燕麦和紫花苜蓿(7∶3)混合青贮发酵品质和有氧稳定性的影响,试验设对照组和3个乙酸添加组(0.3%,0.4%,0.5%),青贮后第30,45和60天开窖取样,测定青贮饲料的发酵品质,同时60 d后打开剩余的所有实验室青贮窖,将青贮饲料暴露于空气中,测定青贮饲料有氧稳定性。结果表明,添加乙酸显著(P<0.05)降低了混合青贮饲料的pH,其中0.4%与0.5%乙酸处理组pH显著(P<0.05)低于0.3%乙酸处理组。青贮60 d后乙酸添加组乳酸含量显著(P<0.05)高于对照组,但处理组间差异不显著(P>0.05)。添加乙酸显著(P<0.05)降低了青贮过程中氨态氮/总氮,且氨态氮/总氮随着乙酸添加量的增加呈下降趋势(P>0.05)。各乙酸添加组水溶性碳水化合物均显著(P<0.05)高于对照组,其中0.4%乙酸添加组最高。在有氧暴露前10 d,各组pH和氨态氮/总氮基本保持稳定,其中乙酸添加组低于对照组。暴露10 d后各组pH均有上升,其中对照组显著(P<0.05)上升。在整个有氧暴露阶段,乳酸和水溶性碳水化合物含量逐渐下降,但各乙酸添加组均显著(P<0.05)高于对照组,其中0.4%乙酸添加组乳酸含量始终保持最高。综合考虑发酵品质和有氧稳定性,0.4%乙酸添加量最适宜。  相似文献   

20.
西藏青稞秸秆与多年生黑麦草混合青贮发酵品质的研究   总被引:3,自引:0,他引:3  
本研究旨在将青稞秸秆与黑麦草以不同比例混合青贮,评价其发酵品质,筛选出适宜的混合比例。试验设青稞秸秆单独青贮(对照组)、80%青稞秸秆+20%多年生黑麦草混贮(L组)、60%青稞秸秆+40%多年生黑麦草混贮(M组)及40%青稞秸秆+60%多年生黑麦草混贮(H组)4个处理。青贮后第7,14和30天后打开青贮窖,测定青贮饲料发酵品质。结果表明,青稞秸秆与黑麦草混合青贮显著(P<0.05)提高了乳酸和水溶性碳水化合物含量,显著(P<0.05)降低了pH值和干物质含量,M和H组在乳酸产生的同时乙酸含量显著(P<0.05)提高,混贮组氨态氮/总氮略低于对照组(P>0.05),各组均显示较低的丙酸和丁酸含量。从秸秆利用最大化的角度出发,建议以40%黑麦草混合青贮较为适宜。  相似文献   

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