北方地区复合碱化、快速氨化玉米秸秆对羊瘤胃消化的影响

本试验研究了复合碱化和快速氨化玉米秸秆组成的全混合日粮对试验羊瘤胃消化的影响。试验表明 ,处理后的秸秆在瘤胃的 4 8h消失率显著提高 ,复合碱化和快速氨化玉米秸秆饲粮对试验羊瘤胃pH值、NH3-N浓度及其动态变化无不良影响。     

北方地区复合碱化、快速氨化处理玉米秸秆对羊生长性能的影响

采用随机区组试验设计,在4℃的外界气温条件下,研究不同处理的全混合日粮对16只雄性德克赛尔与东北半细毛羊杂交一代肉毛兼用羊生长性能的影响。结果表明,以复合碱化、快速氨化处理玉米秸秆为基础的全混合日粮可提高试验羊22.36％、22.50％的采食量;58.04％、58.84％的日增重;耗料增重比降低22.55％、22.89％。     

不同处理玉米秸秆与精粗比饲粮对滩湖F_2代育成公羊瘤胃干物质降解率的影响

为研究不同处理玉米秸秆与精粗比饲粮对滩湖F_2代育成公羊瘤胃干物质降解率的影响,试验采用瘤胃尼龙袋法,选用4只体质量相近、体况健康且装有永久瘤胃瘘管的滩湖F_2代育成公羊,分别测定不同复合氨化处理玉米秸秆和全株玉米青贮饲料及不同精粗比全混合饲粮尼龙袋样品,在其瘤胃培养4、8、16、24、48和72 h时的干物质降解率。结果表明:以复合氨化玉米秸秆为基础即粗饲料60%(氨化玉秸50%+苜蓿干草10%)+精补料40%全混合饲粮和以全株玉米青贮饲料为基础即粗饲料70%(全株玉米青贮30%+苜蓿干草20%+玉米秸秆20%)+精补料30%全混合饲粮在瘤胃内的干物质降解率较高,可以作为宁夏引黄灌区肉羊生产全混合饲粮的推荐配方。     

利用人工瘤胃模拟系统研究秸秆不同处理方式对绵羊体外瘤胃发酵参数的影响

本试验主要是利用人工瘤胃模拟系统研究氨化和青贮处理玉米秸秆饲料对绵羊体外瘤胃发酵参数的影响,试验采用单因素完全随机化试验设计,设计三种日粮,分为A、B、C三组,每组4个重复,A组为对照组,玉米秸秆不经过任何处理;B组为氨化玉米秸秆组;C组为青贮玉米秸秆组。本试验采用自行设计的人工瘤胃体外模拟系统进行体外消化试验。结果表明:A、B、C三个处理组随着培养时间的延长,pH均先下降后趋于平缓然后升高,当饲喂半小时后达到最低,但氨化处理组pH较对照组提高6.47%,差异显著(P 0.05),其他两组差异不显著。三个处理组NH_3-N浓度饲喂2 h后达到最高,氨化处理组NH_3-N浓度高于其他两组,但差异不显著(P 0.05)。氨化组乙酸摩尔比例较青贮组提高8.23%(P﹤0.01),青贮组和氨化组丙酸和丁酸摩尔比例与对照组相比差异不显著(P 0.05)。氨化组总挥发性脂肪酸(TVFA)较青贮组和对照组分别提高50.28%和36.3%,氨化组乙/丙比例较青贮组和对照组分别提高26.67%和49.2%,差异极显著(P﹤0.01)。因此,结果表明氨化玉米秸秆饲料能促进瘤胃发酵,为开发新型饲料资源提供依据。     

不同复合氨化处理稻草及精粗比日粮对滩湖F2代育成公羊瘤胃干物质降解率的影响

为了研究不同复合氨化处理稻草与精粗比日粮对滩湖F2代育成公羊瘤胃干物质降解率的影响,试验采用瘤胃尼龙袋法选择体重相近、体况健康且装有永久瘤胃瘘管的滩湖F2代育成公羊4只,分别测定不同复合氨化处理稻草和全株玉米青贮饲料及不同精粗比日粮在瘤胃培养4,8,16,24,48,72 h的干物质降解率。结果表明:以复合氨化稻草饲料为基础、精粗比为40∶60以及以全株玉米青贮饲料为基础、精粗比为30∶70时全混合日粮干物质降解率表现比较理想,可以作为宁夏地区绵羊肉羊生产全混合日粮的推荐配方。     

玉米秸秆整秸处理技术及营养价值

试验旨在研究玉米秸秆整秸氨化技术及其营养价值。采用化学分析和动物试验方法,测定揉碎氨化、整秸压扁和整秸氨化玉米秸秆的养分含量、养分瘤胃消失率和日粮养分消化率。结果表明,压扁和整秸氨化秸秆的粗蛋白质(CP)含量分别提高(P0.01)127.96%和121.03%,与揉碎氨化秸秆接近,中性洗涤纤维(NDF)含量分别降低8.17%和2.52%,略高于揉碎氨化秸秆;压扁和整秸氨化秸秆干物质(DM)、中性洗涤纤维(NDF)及酸性洗涤纤维(ADF)瘤胃48h消失率显著高于对照组(P0.01),但略低于揉碎氨化秸秆;压扁和整秸氨化秸秆组绵羊瘤胃乙酸、丙酸、总挥发性脂肪酸(TVFA)浓度和纤维素酶活性极显著高于对照组(P0.01),二者与揉碎氨化组没有显著差异。整秸压扁和整秸氨化秸秆的营养价值显著高于对照,但略低于揉碎氨化秸秆,整秸压扁氨化技术略优于玉米秸秆整秸氨化技术。     

不同处理水稻秸秆对体外瘤胃发酵模式、甲烷产量和微生物区系的影响

本试验旨在研究不同处理水稻秸秆对瘤胃发酵模式、甲烷产量和微生物区系的影响。以3头安装有永久性瘤胃瘘管的健康荷斯坦奶牛作为瘤胃液供体,各处理分别以干秸秆(对照)、青贮秸秆、氨化秸秆和碱化秸秆为发酵底物,通过体外产气量法,测定培养72 h内的产气量、甲烷产量、瘤胃发酵参数及瘤胃微生物区系的变化。结果表明:青贮、氨化和碱化处理均显著增加了秸秆体外培养72 h的产气量和24 h的总挥发性脂肪酸浓度(P0.05),碱化处理显著增加了72 h的甲烷产量(P0.05),青贮和氨化处理显著增加了24 h的丙酸含量(P0.05),显著降低了乙酸/丙酸(P0.05)。各处理中以碱化秸秆的产气量(220.3 m L)和甲烷产量(43.23 m L)最高。与未处理的干秸秆相比,氨化和碱化处理显著提高了体外培养24 h培养液中琥珀酸丝状杆菌的相对数量(P0.05),氨化处理显著降低了甲烷菌的相对数量(P0.05),而各处理对培养液中的白色瘤胃球菌、黄色瘤胃球菌、真菌和原虫的相对数量没有显著影响(P0.05)。由此可见,对水稻秸秆进行青贮、氨化和碱化处理,可以不同程度地改变体外瘤胃的发酵模式、甲烷生成以及瘤胃微生物区系的组成;从甲烷减排角度考虑,可选择青贮和氨化的处理方式。     

不同条件处理的氨化玉米秸秆对体外瘤胃发酵的影响

为了研究不同条件处理的氨化玉米秸秆对体外瘤胃发酵的影响,试验采用单因子完全随机分组设计,以3头体况良好、安装永久性瘤胃瘘管的中国荷斯坦奶牛作为瘤胃液供体,各处理分别以经0.15 MPa、0.20 MPa、0.25 MPa三种压强处理的氨化玉米秸秆为发酵底物(以未处理的玉米秸秆作为对照组),通过体外产气法,测定72 h内6个时间点(第3,6,12,24,48,72小时)的产气量及瘤胃发酵参数。结果表明:各处理组体外瘤胃发酵产气量及挥发性脂肪酸浓度均显著高于对照组(P0.05)。0.15 MPa、0.20 MPa及0.25 MPa组的体外瘤胃发酵产气量分别提高了43.68%、29.24%及45.02%。0.25 MPa组产气速度明显高于其他三组。各组体外发酵的pH值(6.72~6.82)、NH_3-N浓度(12.06~13.94 mg/dL)均在正常范围内。与对照组相比,0.15 MPa、0.20 MPa、0.25 MPa组乙酸/丙酸的比例均显著降低,其中以0.25 MPa组的效果最为明显。说明快速氨化处理玉米秸秆可显著提高玉米秸秆中纤维类物质的降解率,从而改变玉米秸秆的体外瘤胃发酵模式,改善玉米秸秆品质的最优氨化处理为0.25 MPa。     

绵羊日粮添加纤维复合酶对瘤胃代谢的影响

研究在玉米秸秆日粮中添加纤维复合酶对绵羊瘤胃代谢的影响。结果发现,在玉米秸秆日粮中添加外源纤维复合酶,使瘤胃液挥发性脂肪酸(VFA)质量浓度显著提高,pH显著下降;提高瘤胃内纤维物质消化率。     

氨化饲料对本地黄牛短期育肥的效果

本地黄牛短期育肥的日粮中，用８０％的氨化、碱化玉米秸秆，并在精饲料中添加０．５％的矿物质，其日增重可达６４２ｇ，只用氨化而不碱化的玉米秸秆效果交。当用氨化料７０％时，虽然日增重可达７２２ｇ，但其每公斤增重的饲料成本则提高１６．７％。饲喂氨化稻草的日增重不如氨化玉米秸杆，而且牛肉中粗蛋白质含量降低。     

The dynamics of the content of ammonia and volatile fatty acids in the rumen fluid during the use of dry feed rations in the cow

The development of the pH-value, the molar quota of volatile fatty acids and of the NH3 content in the change from silage rations to dried rations on the basis of pelleted feed and in dependence on the time after the beginning of feeding was tested in studies of the rumen fluid of four cows in order to explain the causes of the very low NH3 content of the rumen fluid in feeding experiments with rations based on pelleted straw-concentrate mixtures. An influence of the ration type and the time after the beginning of feeding on the molar quota of the individual volatile fatty acids and the NH3 content was ascertained. The ration type tested can cause an NH3 content in the rumen fluid below 1 mmol/l.     

Adaptation of the rumen microbial population to native potato starch degradation determined with the gas production technique and the nylon bag technique

Experiments were conducted to investigate the influence of the adaptation of rumen micro-organisms on the degradation of native potato starch (PS) in the rumen. Cows were fed with rations used for gas production (GP) analysis (dry cows, 1.6% starch) and for the nylon bag (NB) technique (lactating cows, 23% starch, mainly maize starch) and a ration containing 19% native PS (lactating cows). Fermentation characteristics of 13 samples were investigated with the GP technique using rumen fluid from cows fed each of the three rations. The same samples were investigated with the NB technique in the cows obtaining the NB ration and the PS ration. The results showed that the rate of GP was influenced by the source of the rumen fluid. The fermentation rate of PS was considerably enhanced by using rumen fluid adapted to the fermentation of native PS instead of using the other rumen fluids. Incubating in cows fed the PS ration, the rate of PS degradation determined with the NB technique, was higher compared with cows fed other rations. Using the PS ration the observed lag period for PS was shorter. The results show a clear influence of ration on the degradation characteristics of starch, determined with both the GP technique and the NB technique. However, these changes in behaviour did not explain observed differences in amounts of rumen escape PS measured in vivo in animal experiments and in situ, using the NB technique.     

Dependence of rumen fatty acid production on the composition of rations

In three experiments with two Black-and-White dairy cows the influence of soybean oil and coconut fat as well as that of rations rich in roughage and concentrated feed on the production of fatty acids were determined with the isotope dilution method. A change in the method of sampling from the rumen in the course of the investigations resulted in distinctly different absolute production quotas, which can presumably be traced back to the disproportionate mixing in of the isotope and/or different production quotas in various regions of the rumen. The relative differences between the production quotas dependent on the rations, however were approximately the same with both sampling methods, so that they make the comparison of the rations concerning rumen fermentation possible. The production of acetic acid and the total production of fatty acids (C2--C4) correlated closely both with the intake of digestible energy and the intake of digestible organic matter. There was also a highly significant correlation o that they make the comparison of the rations concerning rumen fermentation possible. The production of acetic acid and the total production of fatty acids (C2--C4) correlated closely both with the intake of digestible energy and the intake of digestible organic matter. There was also a highly significant correlation o that they make the comparison of the rations concerning rumen fermentation possible. The production of acetic acid and the total production of fatty acids (C2--C4) correlated closely both with the intake of digestible energy and the intake of digestible organic matter. There was also a highly significant correlation between the relation of acetic and propionic acid in the rumen fluid and the quotient from acetic and propionic acid produced. In contrast to this, a significant relation between the concentration of fatty acids and the production of fatty acids could not be ascertained. Soybean oil and coconut fat brought about a slightly better utilisation of the fat-free organic matter for the production of fatty acids in the rumen. This could mainly be traced back to the increased production of propionic acid. The production of acetic acid per kg fat-free organic matter was insignificantly reduced. A reduced quota of roughage in the ration as well as the use of feed fats resulted in a decrease in the production of acetic acid and an increase in the production of propionic acid. The influence of the quota of roughage, however, was bigger than that of the use of fats. When rations rich in roughage were given, the share the energy contained in the total fatty acids has in the total of the digested energy was, on an average of both animals, slightly lower in comparison to rations rich in concentrated feed. However, the reason for this is not to be found in a lower share the energy digested in the stomachs has in the total of digested energy but in a higher amount of fermentation losses with a nutrition rich in roughage.     

Sugar beet mash silage as a component of a total-mixed-ration for dairy cows--effects on parameters of digestion and animal performance.

Sugar beet mash silage (BMS) was offered in amounts up to 35% of DM to dairy cows as a component of a total-mixed-ration (TMR). Barley and molasses in the control ration were replaced by BMS half in ration BMS 1/2 and in total in ration BMS 1/1 on the basis of the calculated contents of net energy for lactation. Two trials were carried out. In trial I each ration was tested on parameters of rumen fermentation and digestibility of crude nutrients using 4 Holstein cows with rumen fistula. Chewing activity was tested on 2 Holstein cows for each ration. With the BMS rations the ruminal NH3 concentration was lower and the drop in pH was less than in the control ration. The pattern of volatile fatty acids in the rumen fluid from the BMS groups tended towards more propionic and butyric acid. The feeding of BMS showed no negative impact on chewing and rumination. Energy digestibility raised significantly from 59.8% in the control ration to 72.6% in the BMS 1/1 ration. In trial II the same rations were fed in a change-overdesign to a herd of 24 Holstein cows to test feed intake and animal performance. The results showed no significant effects of BMS rations on DM intake and milk production. The results of both trials indicate that even high amounts of cereals can be replaced by BMS without negative effects on rumen fermentation, milk yield and milk composition with slight drop in fat content. For a better handling of BMS, it is of advantage to include it in a TMR.     

The effects of high levels of rumen degradable protein on rumen pH and histamine concentrations in dairy cows

An experiment was conducted to test the hypothesis that the supplementation of crude protein (CP) results in rumen acidosis and increased histamine concentrations in dairy cows. Six ruminally fistulated, non-pregnant dry cows were fed three experimental rations in a replicated 3 × 3 Latin square design. The CP contents in the low-CP, the high rumen undegradable protein (high-RUP) and the high rumen degradable protein (high-RDP) rations were 112, 259 and 266 g/kg dry matter (DM) respectively. The cows were fed 7.7 kg DM of the concentrates and 2.7 kg DM of rice straw. High levels of RDP in the ration significantly increased the ammonia, total volatile fatty acid (VFA) and histamine concentrations in the rumen fluid. However, supplemental CP, whether degradable or undegradable, did not significantly affect the pH of rumen fluid. Plasma urea nitrogen concentration was higher in both high-RDP and high-RUP in relation to cows fed the low-CP ration. The rise in ruminal histamine concentrations was physiologically non-relevant, most likely because rumen pH was not affected by supplemental CP at the installed level of DM intake. Therefore, it can be concluded that the issue of supplemental CP, rumen pH and ruminal histamine concentrations has not yet been settled. Further research is warranted to understand these relationships.     

沙葱提取物对绵羊消化道乳酸菌产共轭亚油酸(CLA)含量的影响

本文选择了4只瘘管蒙古羯羊,通过在绵羊日粮中添加沙葱提取物,采集瘤胃液和食糜,分离和筛选乳酸菌,添加亚油酸培养来研究沙葱提取物对绵羊消化道乳酸菌产共轭亚油酸(CLA)含量的影响。结果表明,沙葱提取物显著提高绵羊瘤胃和十二指肠中乳酸菌的数量和CLA的含量,且十二指肠中的大于瘤胃中的。这为进一步调控绵羊瘤胃内环境,提高羊肉中CLA含量打下基础。     

持续动态瘤胃发酵系统的结构功能比较研究进展

持续动态瘤胃发酵系统是在体外模拟瘤胃内发酵环境,用于瘤胃微生物代谢以及评定日粮营养价值等方面研究的机械装置。该装置是由一系列具有不同功能的设备组成。目前较新的人工瘤胃模拟系统主要能实现发酵环境中各发酵参数的实时监控并对发酵产物如产气量等进行准确计量,但与实体瘤胃内环境还存在一定差距。本文通过对国内外几种典型的持续动态瘤胃发酵系统的各部分结构和功能进行对比分析,比较各自的优缺点,提出了较为合理的设计方法。总之,持续动态瘤胃发酵系统的设计向着自动化方向发展,但在食糜样品的采集方法等方面还需改进。     

The effect of citronellylseneciate on the utilization of feed in sheep

The influence of citronellylseneciate on the digestibility of nutrients and energy, as well as on the level of some rumen and blood metabolites, was studied in feed rations for rams. Citronellylseneciate was not found to have a significant influence on the digestibility of nutrients and energy and nitrogen balance in feed ration. Neither did citronellylseneciate influence the production of total volatile fatty acids and the molar percent of acetic, propionic and n-butyric acids. The addition of citronellylseneciate to feed ration resulted in a decrease in the pH value in rumen and in a non-significant increase in ammonia in rumen and urea in blood. The hematological profile showed increased levels of phosphorus and glutamate-oxalate transferase.     

饲料蛋白质组分对泌乳奶牛乳脂率和乳蛋白的影响

本试验研究采用粗蛋白质相同而蛋白质组分水平不同的四种日粮(日粮粗蛋白质中瘤胃未降解蛋白质(RUP)比例由35.9%逐步提高到40.9%,其他营养成分基本保持一致),选择32头处于中产水平的荷斯坦奶牛,根据产奶量、胎次和泌乳日龄按配对法随机分为四组,研究了不同蛋白质组分水平的日粮对奶牛乳脂率、乳蛋白率和乳蛋白质产量的影响规律。结果表明,粗蛋白质相同而蛋白质组分水平不同的日粮对奶牛乳脂率、乳蛋白率和乳蛋白产量没有显著的影响(P>0.05),但乳脂率有下降的趋势,乳蛋白产量有增加的趋势。     

Effect of type of starch and quantity in rations on apparent and true digestibility of nitrogen and nitrogen balance in sheep

In a digestibility trial 5 semisynthetic rations were fed in 3 periods to 10 male sheep to examine the effects on N balance, components of faecal nitrogen and N digestibility. The rations contained constant amounts of nitrogen but different contents of cellulose and two different types of starch (untreated and steamflaked). Content and type of starch did not show any noticeable effect neither on excretion of undigested dietary nitrogen nor on true digestibility. There could not be noticed any effects on the apparent N digestibility by changing contents of cellulose or untreated starch. If the rations contained steamflaked corn starch, the animals excreted more faecal nitrogen and therefore showed a lower apparent N digestibility. Especially the water soluble N fraction of the faecal nitrogen was clearly higher. Compensation took place through a lower N excretion with the urine. The reason for increased faecal N excretion may be higher microbial protein synthesis in the rumen. This was accented by the allantoin excretion with the urine.