藏系绵羊瘤胃细菌区系的季节动态分析

本文旨在研究不同季节牧草营养成分变化及藏系绵羊瘤胃细菌区系的季节动态变化.试验在不同季节分别随机选取3只藏系绵羊,采用PCR-DGGE技术对12只藏系绵羊瘤胃内容物中的细菌区系进行分子生态学的分析,对细菌16S rDNA的V6～V8可变区的扩增产物进行DGGE图谱分析、相似性分析和Shannon多样指数分析.结果表明:(1)秋季瘤胃细菌种群丰富度极显著(P<0.01)高于冬、春季节,显著(P<0.05)高于夏季,而其他3个季节之间差异不显著(P>0.05);(2)瘤胃细菌区系组成结构在春季和夏季相似性高于90%,在秋、冬季相似性低于70%,而春、夏季与秋、冬季之间的相似性低于60%;(3)夏季牧草中DE和CP含量极显著(P<0.01)高于其他季节,其瘤胃液pH极显著(P<0.01)低于其他季节,瘤胃细菌区系丰富度也相应降低;秋季牧草的DE和CP含量显著(P<0.05)高于春、冬季节,其瘤胃液pH范围为7.1～7.3,瘤胃细菌区系丰富度高于其他3个季节.由以上结果可以看出,不同季节瘤胃内优势菌群发生了改变,瘤胃细菌区系的季节变化与瘤胃pH、瘤胃内容物的物理特性、营养成分及其比例等有关.     

不同物候期牧草对藏系绵羊血清生化指标、瘤胃内环境参数及瘤胃微生物功能菌群的影响

本试验旨在研究不同物候期牧草对藏系绵羊血清生化指标、瘤胃内环境参数及瘤胃微生物功能菌群的影响.分别于高寒草甸返青期、青草期和枯草期采集牧草样品,测定常规营养成分含量.选取体重为(34.08±2.94) kg的10只4岁全年放牧的藏系母绵羊,用耳标进行标记,分别于返青期、青草期和枯草期清晨放牧前空腹进行颈静脉采血及瘤胃液...     

藏系绵羊瘤胃细菌数量及其放牧地牧草养分随季节变化的研究

试验分别于春、夏、秋和冬季,随机选择3只同群常年放牧健康的藏系绵羯羊(2岁),屠宰后采集瘤胃内容物。采用瘤胃细菌通用引物和实时定量PCR技术,研究瘤胃细菌数量随季节的动态变化。结果表明,1)夏季瘤胃细菌数量显著(P＜0.05)高于其他3个季节,分别是春季、秋季、冬季细菌数量的5.56,2.35和2.49倍;秋、冬季是春季细菌数量的2.38和2.23倍;而秋和冬季瘤胃细菌的数量差异不显著(P＞0.05)。2)夏季藏系绵羊采食量分别为春季、冬季和秋季的1.98,1.61和1.80倍,饲料中的纤维性物质含量增高,采食量也随着降低,瘤胃细菌的数量也相应降低;3)实时定量PCR技术能准确的反映出放牧藏系绵羊瘤胃细菌数量随季节的动态变化。     

藏系绵羊对高寒环境适应性研究

藏系绵羊(Tibetan sheep)是分布于青藏高原上的特有家畜品种之一.采用RA(C)Ⅲ型密闭回流式呼吸测热装置,将温度控制在5℃、10℃、15℃、20℃、25℃、30℃、35℃梯度内,测量不同温度下藏系绵羊呼吸频率及直肠温度.当环境温度为 12.45℃时,产热量最小值为267.60 KJ*d-1*w-0.75.藏系绵羊的热中性区是8～15℃ ,与其它地区绵羊相比(10～20℃),热中性区更为狭窄,且临界温度下限更低,从而表现出适应寒冷气候条件的生存特征.     

若尔盖县牦牛及藏系绵羊寄生虫病调查

本文通过剖检20头牦牛和镜检30份新鲜藏系绵羊粪便,对若尔盖县牛羊进行了寄生虫病调查。结果表明:感染牛羊的寄生虫主要为前后盘吸虫、鞭虫、仰口线虫、绦虫和牛蝇蛆,其中前后盘吸虫的危害最大。     

半胱胺对藏绵羊断奶羔羊瘤胃pH值、总脱氢酶及TVFA的影响

试验研究了半胱胺(Cs)对藏绵羊断奶羔羊瘤胃pH值、总脱氢酶及TVFA的影响。将10只(公母各半)80日龄左右、体重平均为(16.00±0.31)kg、装有永久性瘤胃瘘管的藏绵羊断奶羔羊随机分为2组(试验组和对照组),在日粮精料中添加300 mg/(kg·BW)的Cs,隔日添加1次,试验期42 d。正式试验当日及试验第7、14、21、28、35天的7:00、9:00、11:00、13:00、15:00、17:00、19:00、21:00、23:00、1:00、3:00、5:00于颈静脉采血样10 mL,同时采集瘤胃液10 mL,测定瘤胃pH值、总脱氢酶的活性和TVFA。检测结果表明,试验组精料中添加Cs使藏绵羊断奶羔羊瘤胃液pH值升高;血清尿素氮浓度降低,与对照组相比差异极显著(P0.01);瘤胃液总脱氢酶活力提高极其明显(P0.01);整个试验期内,半胱胺对瘤胃TVFA的影响极显著(P0.01)。     

硒对热应激条件下放牧绵羊瘤胃发酵及瘤胃微生物区系的影响

为探讨热应激条件下补硒对放牧绵羊瘤胃发酵以及瘤胃微生物区系的影响,试验选择体重相近、健康的7～8月龄杜寒杂交羊10只,采用单因素完全随机试验设计,随机分成2组,每组5只.对照组不添加硒,试验组硒添加水平为0.2 mg/d(硒源为酵母硒).在夏季温度最高的初伏到中伏期间,以自然放牧方式饲养20 d后,颈静脉采集血液测定血...     

不同精料补饲水平对藏绵羊瘤胃内环境参数的影响

选择1.2岁左右藏绵羊30只,随机分3组,采用单因子分组设计,以青干草为基础日粮,按每只150,300,450 g/d 3种精料水平补饲,研究不同精料补饲水平对藏绵羊瘤胃代谢参数变化规律的影响。结果表明;随精料补饲水平提高,藏绵羊瘤胃液pH值下降,NH3-N浓度、NH3-N浓度平均值、总挥发性脂肪酸(VFA)浓度显著增加(P<0.05)。在本试验条件下,从藏绵羊瘤胃内环境的稳定方面考虑,藏绵羊每日补饲精料300 g效果最佳。     

青海藏系绵羊毛囊生长周期性变化的研究

对青海藏系绵羊皮肤切片进行H.E.染色的组织形态学观察显示,青海藏系绵羊皮肤毛囊在2月份处于休止期、5月份处于兴盛前期、8月份处于兴盛期、11月份进入退行期;初级毛囊密度活动变化较次级毛囊密度活动变化恒定,S/P值明显低于其他品系绵羊;毛囊群以一元体和二元体毛囊群居多,三元体毛囊群较少。     

藏系绵羊遗传多样性的研究进展

本文系统的论述了藏系绵羊在表型和地域、形态学遗传标记、细胞学遗传标记、生化遗传标记和分子遗传标记等不同方面的遗传多样性研究的概况,说明了藏系绵羊的遗传多样性研究目前仍处于起步水平,因此有必要对藏系绵羊的遗传多样性进行更深入的研究,尤其加强DNA分子水平上的研究。     

Effect of monensin on rumen ciliate protozoa in sheep

In a first experiment 4 rams consumed over a period of 70 days 0; 82; 208 and 345 mg of monensin daily, respectively. All doses of monensin caused a marked decrease in total numbers of rumen protozoa in samples taken after this period. More than 90% of total protozoal numbers belonged to the genus Entodinium. The sensitivity of the genus Entodinium to monensin was found to be lower than that of genera Dasytricha and Isotricha. In the second experiment 24 lambs were fed hay and concentrates in the ratio 60:40% (groups 1 and 2) and 40:60% (groups 3 and 4). Groups 2 and 4 received 40 mg monensin per animal daily during 16 weeks. The decrease in protozoal numbers due to monensin in samples taken after this period was significant (P less than 0.001) in lambs fed the concentrate diet (groups 3 and 4) and also in lambs from groups 1 and 2 fed the roughage diet (P less than 0.05). The statistical evaluation of the inhibition of total protozoal numbers by monensin (%) in lambs fed both diets has shown that the antiprotozoal effect of monensin was significantly more intensive with the concentrate diet (P less than 0.025) than with the roughage diet.     

西藏林芝地区羊心电图和瘤胃肌电图特征分析

通过对正常藏系绵羊心电图和瘤胃肌电图的分析,掌握反刍动物的循环和消化代谢的特点。固定试验绵羊,利用心电图仪和胃肠电图仪进行描记,发现心电轴普遍右偏,偏移角度130°以上(P0.05);T波显著增高,在V1、V2、V3和V4 4个胸导联中,T值均值为(0.44±0.16)、(0.73±0.35)、(0.53±0.17)、(0.43±0.47)mV;ST段等电位的时间0.12s,QT间期水平延长。瘤胃肌电的描记发现VPP电位随年龄增加而降低,主波时间随年龄增加而变短。结果表明:心电轴的右偏与右心室肥大或品种有关,T波电位的增加与缺钙、高血钾或品种相关;瘤胃收缩的强度与收缩时间随年龄增加而变弱变短,此结果可为高原藏系绵羊内科疾病提供诊断方法和基础依据。     

不同饱和度脂肪添加抗氧化剂对瘤胃发酵、抗氧化状态和微生物区系的影响

利用体外产气法研究不同饱和度脂肪和抗氧化剂添加对湖羊瘤胃体外发酵参数的影响。试验采用2×2因子设计,试验因素为脂肪类型(全饱和与50%饱和度)和抗氧化剂(0或500mg/kg)。结果显示,脂肪类型不影响瘤胃发酵参数和抗氧化状态(P>0.05),与饱和脂肪相比,补充不饱和脂肪可显著降低瘤胃液中产琥珀酸丝状杆菌相对于总菌的比例(P<0.05)、提高原虫的比例(P<0.05)。添加抗氧化剂可提高瘤胃体外24h产气量和有机物消化率(P<0.05),并有减少乙酸摩尔比、增加丙酸摩尔比的趋势(P<0.10)。添加抗氧化剂有降低瘤胃丙二醛、提高超氧化物歧化酶活性的趋势(P<0.10)。抗氧化剂对黄色瘤胃球菌和白色瘤胃球菌的影响与脂肪类型有关,不饱和脂肪添加抗氧化剂可显著提高黄色瘤胃球菌和白色瘤胃球菌相对于总菌的比例,而饱和脂肪添加无显著影响。上述结果表明,日粮添加不饱和脂肪不利于纤维分解菌的生长,添加抗氧化剂可改善不饱和脂肪对瘤胃微生物的影响,而对饱和脂肪影响较小;添加抗氧化剂还可改善瘤胃抗氧化状态、提高有机物的消化率。     

体外产气法研究不同钾水平日粮对绵羊瘤胃发酵的影响

<正>近年来通过调控瘤胃发酵来提高反刍动物饲料转化率及生产性能一直是反刍动物营养研究的重点之一。钾对瘤胃微生物的生长以及瘤胃发酵都是必需的,不同钾水平的日粮在很大程度上影响了瘤胃发酵模式及动物的生产性能。20世纪90年代初以来,体外产气法由于能够较好地模拟瘤胃中的发酵历程和     

Effect of monensin on fermentation pattern and soybean protein degradation in the rumen of sheep

The effect of a daily dose of 30 mg Monensin on rumen fermentation pattern and degradation of the crude protein fraction of soybean meal was investigated with sheep. Degradation parameters for soybean meal were measured by the nylon bag technique. Monensin increased propionic acid percentages in the rumen, with a concomitant decrease in acetic- and butyric acid proportions, thus confirming earlier work. Ammonia N concentration in the rumen was also lowered, indicating an inhibitory effect on rumen protein breakdown. However, no effect on degradation rate, degradability and effective degradability (only with one sheep) could be observed. Possible reasons for these findings are discussed. Amino acid analysis on the residues in incubated bags revealed slight changes in amino acid composition, but these changes were considered to be nutritionally unimportant.     

矿物质元素硫对绵羊瘤胃纤维物质降解的影响

试验选择6只健康的、体重相近且安装永久瘤胃瘘管的内蒙古半细毛羯羊为试验动物,采用半体内法研究不同硫源对绵羊纤维物质瘤胃降解率。结果表明,添加不同硫源后,与对照组基础日粮DM、NDF、ADF的有效降解率P值相比,其瘤胃降解模型参数a、b、c和P值发生了显著变化;DM有效降解率Na2SO4组最大为64.11%,差异极显著高于对照组(42.27%)(P<0.01),Na2S组(48.29%)和对照组(42.27%)以及Na2SO4组和Na2S组DM的有效降解率差异显著(P<0.05);NDF的有效降解率Na2SO4组为52.69%,Na2S组为50.94%,两组差异不显著(P>0.05),但都显著高于对照组(42.01%)(P<0.05);ADF有效降解率Na2S组最大,为73.45%,Na2SO4组为70.36%,两组差异不显著(P>0.05),但都极显著高于对照组(54.12%)(P<0.01)。     

吐温对绵羊采食、瘤胃代谢、CMCase活力和原虫数量的影响

以4只装有永久性瘤胃瘘管的新疆美利奴羊为试验动物,采用4×4拉丁方设计,研究添加10g/d的吐温对绵羊瘤胃消化代谢的影响。在4期试验中每只羊分别添加吐温40、吐温60、吐温80或不添加任何吐温。结果表明:添加吐温对绵羊粗饲料及部分营养物质采食量无显著影响;添加吐温40和吐温60对瘤胃液pH值和氨态氮无显著影响,但吐温80可显著降低瘤胃pH值(P<0.05),对氨态氮浓度无显著影响;与对照组相比,添加吐温60和80使总VFA浓度分别提高8.25%和13.01%,添加吐温60可使乙、丙、丁酸平均浓度分别提高7.94%、9.09%和8.56%(P<0.05),添加吐温80可使乙、丙、丁酸平均浓度分别提高12.19%、14.23%和15.59%(P<0.01);添加吐温60和80分别使CMCase活力提高12.85%和18.71%(P<0.05);添加吐温对瘤胃液中原虫数量均无显著影响。以上结果显示,吐温对绵羊瘤胃发酵调节作用的大小依次为吐温80>吐温60>吐温40,其中吐温60和80可能是值得开发的新型反刍动物饲料添加剂。     

Influence of kanamycin on the rumen bacteria and ammonia production in supplemented sheep rumen liquor in vitro

Bacteriological studies were made with in vitro sheep ruminal fluids supplemented with synthetic fodder containing different amounts of kanamycin (0.125, 2.50, and 60 mg/ml), during anaerobic incubation at 38–39°C for 6 h.Changes in the bacterial population occurred in the presence of large amounts (60 mg/ml) of kanamycin, and the B₁-type strain of Eubacterium became predominant.The marked increase in the concentration of ammonia in the supplemented rumen liquor, obtained after anaerobic incubation with high dosages of this antibiotic, is discussed.     

Effect of several supplemental Chinese herbs additives on rumen fermentation, antioxidant function and nutrient digestibility in sheep

Two experiments were carried out in this study. Experiment 1 was conducted to examine the effects of several supplemental Chinese herbs on antioxidant function and slaughtered body weight in sheep. Results indicated that Fructus Ligustri Lucidi supplementation improved the blood antioxidant function [higher concentration of glutathione reductase (GR), superoxide dismutase and lower concentration of malondialdehyde] and slaughtered body weight in sheep (p < 0.05). Experiment 2 was conducted to investigate the effect of Fructus Ligustri Lucidi extract (FLLE) on rumen fermentation and nutrient digestibility in sheep. Four levels of FLLE treatments, i.e. 0, 100, 300 and 500 mg/kg dry matter (DM), were used in this part. Addition of FLLE at 300 or 500 mg/kg DM increased total volatile fatty acid (VFA) concentration and propionate proportion, decreased ammonia-N concentration in the ruminal fluid, reduced blood urea nitrogen concentration at 2, 4, 6 and 8 h after morning feeding (p < 0.05). Addition of FLLE at all dosages had no effect on ruminal pH value and acetate concentration at all sampling time points in sheep (p > 0.05). Dynamic degradation coefficient c of maize DM was significantly increased by supplementing FLLE at 300 or 500 mg/kg DM (p < 0.05). Fructus Ligustri Lucidi extract addition had no effect on degradation coefficients a, b, c of DM and nitrogen of soybean meal; a, b of maize DM; a, b, c of maize nitrogen; and a, b, c of neutral detergent fibre (NDF) and acid detergent fibre (ADF) of Chinese wildrye (p > 0.05). Addition of FLLE at 300 or 500 mg/kg DM increased DM and organic matter digestibility of diet (p < 0.05). Fructus Ligustri Lucidi extract addition had no effect on digestibility of diet's NDF, ADF and crude protein (p > 0.05). From the aforementioned results, it is indicated that FLLE improved antioxidant status and slaughtered body weight. Fructus Ligustri Lucidi extract addition has capability to modulate rumen fermentation, increase the maize degradation rate, total volatile fatty acid concentration and propionate proportion in sheep.