全混合颗粒料中添加不同类型蛋氨酸对湖羊生长性能及血清生化指标的影响

本试验旨在研究在湖羊全混合颗粒料中添加不同类型蛋氨酸(蛋氨酸钙盐与蛋氨酸羟基类似物异丙酯)对湖羊生长性能及血清生化指标、抗氧化指标和激素含量的影响.选取体重为(19.99±2.04)kg的健康湖羊72只,随机分为3组:对照组、试验Ⅰ组(在基础饲粮中添加1.5 kg/t蛋氨酸钙盐)和试验Ⅱ组(在基础饲粮中添加1.5 kg...     

青海省藏羊感染皮蝇蛆调查及其虫种鉴定

为了解青海省藏羊感染皮蝇蛆状况及感染种类,本研究在3个地区调查了476只藏羊,对2株感染藏羊皮蝇蛆和4株感染牦牛皮蝇蛆的线粒体CO1基因种属特异性序列进行比较研究。结果表明:14只羊感染了皮蝇蛆,感染率为2.9%,总瘤胞数为27个,平均感染强度为1.9个;并扩增其长度为688 bp的序列,克隆后测序,将其序列与GenBank中的牛皮蝇、纹皮蝇蛆和中华皮蝇蛆序列进行聚类分析,结果显示青海省感染藏羊的皮蝇蛆与感染牦牛的果洛株、民和和黄南株在线粒体CO1基因片段聚类分析进化树和同源性比较中,与牛皮蝇位于同一个进化树分支上,基因片段同源性大于99%,为牛皮蝇;感染牦牛的海晏株和贵南株在线粒体CO1基因片段聚类分析进化树和同源性比较中,与中华皮蝇位于同一个进化分支上,基因片段同源性大于99%,为中华皮蝇。几个皮蝇蛆分离株种内变异率小于1%,种间变异率大于8%。     

Dairy sheep production research at the University of Wisconsin-Madison,USA-a review

Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 yr ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 yr. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural Research Station of the University of Wisconsin-Madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk production to supplements high in energy and/or     

瘤胃乙酸、丙酸比例对绵羊体内氧化代谢和血浆胰岛素水平动态变化的影响

本研究以全胃营养灌注绵羊为试验动物 ,用物质代谢区室分析方法和同位素示踪技术研究了瘤胃乙酸、丙酸比例对体内氧化代谢和血浆胰岛素水平动态变化的影响。不同试验处理间营养灌注液能量、蛋白质水平相同 ,而瘤胃灌注混合挥发性脂肪酸的乙酸、丙酸比例不同。三种混合挥发性脂肪酸的乙酸、丙酸比例分别为75 :15(VFA1)、65 :25(VFA2)、45 :45(VFA3)。由测定引入 14C -乙酸后血液二氧化碳放射比强度—时间曲线上升段斜率(k值)反映体内氧化代谢强度。试验结果为 ,瘤胃灌注VFA1 时的k值显著高于灌注VFA2 和VFA3 时的k值(P<0.05) ,而VFA2 和VFA3 两处理间的差异不显著(P>0.05) ,说明瘤胃灌注VFA1 时绵羊体内氧化代谢强度增加。向停止灌注24小时的绵羊瘤胃内灌注VFA1,血浆胰岛素水平在恢复灌注后缓慢上升。将瘤胃灌注混合挥发性脂肪酸由VFA1 换为VFA2 后 ,血浆胰岛素水平迅速上升 ,之后迅速下降 ,而由VFA2 换为VFA3 后未出现血浆胰岛素水平的明显变化 ,说明血浆胰岛素水平的变化与体内糖代谢调节状态有关 ,而瘤胃灌注VFA1 时的体内糖代谢调节状态与灌注VFA2 和VFA3 时明显不同。     

Effect of supplementing urea-treated barley straw with lucerne or vetch hays on feed intake,digestibility and growth of Arsi Bale Sheep

The study was conducted at Sinana Agricultural Research Center, Ethiopia to assess the supplementation of graded levels of vetch (Vicia dasycarpa `lana’) and lucerne (Medicago sativa,’ Hunter river’) hay on feed intake, digestibility and body weight (BW) change of Arsi-Bale sheep fed urea treated barley straw (UTBS). A 7 day- digestibility and a 90 day- feed intake trials were conducted using 28 and 35 sheep, respectively. The experimental design was a randomized complete block design with seven dietary treatments that consisted of feeding UTBS (T1) as the control treatment, UTBS plus 150, 250 and 350 g dry matter (DM) per day of vetch for T2, T3, T4, respectively and UTBS plus 150, 250 and 350 g DM per day of lucerne for T5, T6 and T7, respectively. Intake of UTBS was not affected (P > 0.05) by inclusion of lucerne hay at 25–35% of daily DM intake. The supplements increased daily intake of total DM, organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF) and metabolizable energy (ME) (P < 0.001) as well as apparent digestibility of DM, OM (P < 0.001), NDF (P < 0.01), ADF, crude protein (CP) (P < 0.05) and daily BW gain (P < 0.001). Supplementation with lucerne than vetch hay promoted higher (P < 0.001) CP and ME intakes and daily BW gain. Feeding with the UTBS without supplementation was enough to meet the maintenance requirements of the sheep and allow small BW gain. The results of the study showed that urea treatment of barley straw in conjunction with supplementation of lucerne or vetch hay could serve as a useful strategy in improving smallholder sheep production in the tropics.     

Comparative fluorescein angiography of the normal sheep and goat ocular fundi

Fluorescein angiography without sedative or anesthetic agents was evaluated in 20 normal goats and 20 normal sheep. All of the angiographic phases were observed using 20 mg/kg fluorescein IV in both species. Fundus fluorescein angiography results revealed wide stars of Winslow in the tapetal fundus, central or marginal flow during the first part of the arterial phase, delayed filling of the focal areas in the choroid near the optic disc that often coincided with others in the disc, and lack of evidence of the 'striate area' in the tapetal fundi. In goats, the angiographic times were 6.54+/-1.25 s for the arterial phase (TA), 7.80+/-1.37 s for the arterio-venous phase (TAV), and 14.13+/-2.01 s for the venous phase (TV). I1: 1.30+/-0.30 s (time elapsing between TA and TAV), and I2: 6.20+/-1.60 s (time elapsing between TAV and TV). In sheep, times were 9.54+/-2.18 s TA, 11.73+/-2.10 s TAV, and 20.86+/-2.74 s TV. I1: 2.04+/-0.75 s and I2: 8.98+/-2.47 s, respectively. Due to the large size of the fundic vessels in sheep and goats, fluorescein angiography of the retinal vasculature can facilitate the study of the different vascular diseases in these species.     

欧拉型藏羊生长发育规律的研究

对欧拉型藏羊从初生到18月龄不同月龄体重、体尺的测定和分析表明,欧拉型藏羊在自然放牧、无补饲条件下,早期生长发育快,肉用体型较明显,10月龄体重接近40kg;6月龄后日增重随着月龄的增长呈递减趋势,10月龄以前生长发育性别间无显著差异;10月龄以后进入枯草季节,其生长发育基本处于停滞状态;18月龄时,公羊体重明显大于母羊,这与公羊在冬春季有少量补饲有直接关系。     

绵羊胚胎移植生殖内分泌调控及其效果研究

初产供体母羊（14月龄）德国美利奴15只、波德代15只、无角陶赛特18只分别用孕酮(CIDR)+促性腺激素(PMSG)+促卵泡素(FSH)进行处理,受体小尾寒羊母羊（2胎）124只用CIDR+PMSG进行处理,处理期测定供、受体外周血液中生殖激素孕酮（p4）、雌二醇（E2）、促卵泡素（FSH）和促黄体素（LH）的动态变化。结果显示：3个供体品种和受体各自发情同期化水平和效果达到非常理想的状态,但供、受体发情同步差相距1 d。黄体数德国美利奴（7.71）显著高于陶赛特（5.19）（P<0.05）;冲卵数德国美利奴（5.50）显著高于陶赛特（3.44）（P<0.05）;可用胚胎率德国美利奴、波德代、陶赛特分别为70.13%、55.74%、78.18%,陶赛特显著高于波德代（P<0.05）;德国美利奴、波德代、陶赛特胚胎移植受胎率分别为55.26%、54.17%、42.31%,德国美利奴显著高于陶赛特（P<0.05）。处理期供体和受体生殖激素动态变化的幅度大,第13天供、受体血清中p4达到峰值,小尾寒羊分别高于德国美利奴（5.37 ng/mL）、波德代（6.14 ng/mL）和陶赛特（5.37 ng/mL）;供体血清中E2于第14天开始发情达到峰值,小尾寒羊于第15天开始发情达到峰值;供体血清中FSH于第13天达到峰值,小尾寒羊第14天达到峰值;供体血清中LH于第14天开始发情达到峰值,小尾寒羊血清中LH于第15天开始发情达到峰值。     

杜仲叶影响绵羊血清代谢组学的研究

为探索杜仲叶（Eucommia ulmoides leaves,EUL）对绵羊营养代谢和生理功能的影响,本研究选取25~30 kg、70~80日龄的湖羊30只,随机分为3组,每组10只,分别为对照组（无杜仲叶日粮组,CTL）、低剂量添加组（10%杜仲叶日粮组,EUL1）、高剂量添加组（20%杜仲叶日粮组,EUL2）。预试期15 d,正试期90 d。试验结束时,通过静脉采血,离心后分别取血浆和血清,血浆用于生化分析,血清用于代谢组学分析。结果显示,饲喂杜仲叶后,EUL1和EUL2组绵羊血浆中葡萄糖、非酯化脂肪酸、高密度脂蛋白和极低密度脂蛋白均升高,EUL2组与CTL组差异显著或极显著（P<0.05;P<0.01）,EUL1组与CTL组差异不显著（P>0.05）;EUL1和EUL2组尿素较CTL组极显著降低（P<0.01）,总胆固醇水平显著降低（P<0.05）,EUL1和EUL2组间差异不显著（P>0.05）。血清样品采用液相色谱-质谱联用仪（LC-MS）进行检测,在正模式下得到593个代谢物,在负模式下得到1 570个代谢物。通过主成分分析（PCA）、偏最小二乘判别分析（PLS-DA）及正交偏最小二乘判别分析（OPLS-DA）发现,各试验组间的差异代谢物较多,能将其得分图明显区分。进一步对变量重要性因子大于1.0（VIP>1.0）的代谢物进行t检验后发现,各组之间有24种特征代谢物差异显著（P<0.05）。这些差异代谢物涉及体内葡萄糖、脂肪酸和氨基酸等的代谢,有的代谢物还与动物的免疫机能相关。杜仲叶饲料对绵羊的营养代谢、生理状态和免疫状况可产生明显的影响,代谢组学可有针对性地分析代谢物发生的步骤及生理作用,为阐明杜仲叶影响营养代谢的机制提供参考。     

转化生长因子βⅠ型受体基因在敖汉细毛羊不同组织及发情时期卵巢中的表达分析

试验旨在探究转化生长因子βⅠ型受体（transforming growth factor-beta receptorⅠ,TGF-βRⅠ）基因在敖汉细毛羊中的组织表达情况,以及在不同发情时期卵巢中表达量的变化规律,为探讨其与绵羊发情的关系奠定基础。以24只季节性发情的敖汉细毛羊为研究对象,分为乏情期、发情间期、发情前期和发情期4组,每组6只。首先利用实时荧光定量PCR检测其发情期甲状腺、下丘脑、垂体、卵巢、肾上腺、心脏、肝脏、脾脏、肺脏、肾脏、胰腺、肌肉12个组织中TGF-βRⅠ基因的表达情况,其次对4个不同发情时期卵巢TGF-βRⅠ基因的表达量变化进行研究。结果显示,TGF-βR Ⅰ在各组织中均有表达,在卵巢和甲状腺中表达量最高,极显著高于其他组织（P<0.01）;在下丘脑、垂体、胰腺、肾上腺、脾脏和肺脏组织表达量较高,显著高于心脏、肝脏、肾脏和肌肉组织（P<0.05）。卵巢中TGF-βRⅠ基因在发情前期表达量最高,极显著高于其他3个时期（P<0.01）,发情间期表达量最低,极显著低于其他3个时期（P<0.01）。综上所述,卵巢组织中TGF-βRⅠ基因在发情前期时可能对排卵前卵泡的成熟起促进作用。