Epostane对公兔血清睾酮、皮质醇的影响

将不同剂量的Ｅｐｏｓｔａｎｃ静脉注射成年公兔，测定注射后１、２、３、２４小时血清睾酮、皮质醇水平的变化。结果显示注射Ｅｐｏｓｔａｎｃ后公兔血清睾酮水平增加且与剂量相关；低剂量Ｅｐｏｓｔａｎｃ显著地降低血清皮质醇水平。     

湖南省某生猪批发市场疫病传播风险评估

为评估湖南省某生猪批发市场猪群疫病的发生风险,找出可能的风险因素,便于提出针对性预防措施,采用自行设计的调查问卷,结合访谈和现场调查,对27户经营户进行了调查,并将调查结果和调运数据相结合进行了疫病传播风险定性评估。结果显示:该市场疫病传入的可能性"高",内部传播的可能性"中等",疫病传出的可能性"高"。生猪调运频次多、数量大,经纪人行为复杂,运输车辆清洗消毒不彻底是可能的风险因素。评估结果提示,应尽量减少经纪人行为影响,重点加强对运输车辆的清洗消毒。     

Identification of lactic acid bacteria in the feces of dairy cows fed whole crop maize silage to assess the survival of silage bacteria in the gut

In order to assess the survival of lactic acid bacteria (LAB) in whole crop maize silage in the gut of dairy cows, one representative silage sample and three different feces samples were collected from dairy cows on three dairy farms in Hua Bei, China and three dairy farms in Kyushu, Japan. The composition of the bacterial community was examined by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction. Lactobacillus acetotolerans was detected in all bunker‐made maize silage samples, regardless of the dairy farm or sampling region from which they were sourced. A total of eight LAB species were detected in the maize silage samples, of which three (L. acetotolerans, L. pontis and L. casei) appeared to survive digestion. The populations of L. acetotolerans in silage and feces were 10^6–7 and 10^3–4 copies/g, respectively, indicating that, even for the LAB species showing potential survival in the gut, competition in this niche may be harsh and the population may substantially decrease during the digestion process. It may be difficult for silage LAB to survive in the gut of silage‐fed dairy cows, because marked decrease in population can take place during the digestion process, even for surviving species.     

犊牛开食料研究报告

设计了一种犊牛开食料配方,干物质营养成分为:代谢能13.0MJ/kg、粗蛋白21％、钙1.1％、磷0.56％,铁110mg/kg、锰133mg/kg、铜33mg/kg、锌167mg/kg、碘1.4mg/kg、硒0.88mg/kg、钴1.1mg/kg、维生素A 11000 IU/kg、维生素D_32780 IU/kg、维生素E 133 IU/kg。20头新生犊牛经配对试验采食按该配方生产的饲料。结果发现,试验组犊牛的平均日耗料量极显著增加40g(P<0.01),另外腹泻发生率显著降低(P<0.05)。而犊牛血清钙、磷、铁、葡萄糖和总蛋白的浓度都在正常范围之内。试验表明,该颗粒料适口性良好,可以促进犊牛的采食和断奶,并可减少腹泻的发生。     

四季鹅产蛋前后腺垂体远侧部细胞的超微结构比较

对处于产蛋、停产和产前等不同时期的四季鹅腺垂体远侧部分泌促激素的６类细胞,即促生长激素细胞（α细胞）、催乳激素细胞（η细胞）、促卵泡形成激素细胞（β细胞）、促黄体生成激素细胞（γ细胞）、促甲状腺激素细胞（δ细胞）及嫌色细胞等的超微结构作了比较观察。结果表明,产蛋期嗜碱性β、γ和δ细胞呈旺盛的细胞结构象,细胞器结构发达,腺体功能活跃;停产期特征是η细胞稍增多,细胞器少,腺体功能处于相对静止;产前期仅α细胞功能活跃,嫌色细胞数量较多,此时腺体功能低下。     

甘谷县跨省调入动物落地监管工作存在的问题及对策

跨省调入动物落地监管作为防控动物疫病的关键环节,对有效遏止动物疫病传播、保障畜产品质量安全和公共卫生安全具有重要意义,本文就我县跨省调入动物落地监管中存在的问题和对策进行分析和探讨。     

中国河西走廊草地农业的基本格局和它的系统相悖─—草原退化的机理初探─—

河西走廊的草地资源位于西北荒漠的大背景中，由山地、荒漠和绿洲三个子系统构成，其中荒漠子系统居主导地位，具有先天的脆弱性。它们在人为干预下，在自然生态系统的农业化过程中，发生了山地一绿洲一荒漠组成的耦合农业系统。由于耦合不够完善，它所固有的相悖因素未能有效控制，形成涵有系列相悖因子群的系统相悖。主要表现为时间相悖，空间相悖和种间相悖。三者互相影响，但时间相悖起主导作用，使系统的生态危机加剧。它通常表现为草原退化。对草地农业生态系统的自由能的调控，保持自由能的积累和输出基本相当，是防止草原退化的根本出路。草原退化是草地对于草食动物压迫的对策系统和动物对于草地负荷行为的对策系统的综合反映。放牧程度可以作为草原退化过程的向量系统，但不是草原退化的本质。     

益生菌发酵饲料对猪的生长和肉质的影响

应用益生菌发酵饲料喂猪,能提高饲料中粗蛋白含量,明显降低猪粪臭味,促进生长、降低料肉比和提高猪肉品质。     

Pharmacokinetics and bioavailability of valnemulin in broiler chickens

Wang, R., Yuan, L.G., He, L.M., Zhu, L.X., Luo, X.Y., Zhang, C.Y., Yu, J.J., Fang, B.H., Liu, Y.H. Pharmacokinetics and bioavailability of valnemulin in broiler chickens. J. vet. Pharmacol. Therap. 34 , 247–251. The objective of this study was to investigate the pharmacokinetics and bioavailability of valnemulin in broiler chickens after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 10 mg/kg body weight (bw). Plasma samples were analyzed by high‐performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS). Pharmacokinetic characterization was performed by non‐compartmental analysis using WinNonlin program. After intravenous administration, distribution was wide with the volume of distribution based on terminal phase(V_z) of 4.27 ± 0.99 L /kg. Mean valnemulin t_1/2β(h), Cl_β(L /h /kg), V_ss (L /kg) and AUC_(0–∞)(μg·h /mL) values were 2.85, 0.99, 2.72 and 10.34, respectively. After intramuscular administration, valnemulin was rapidly absorbed with a C_max of 2.2 μg/mL achieved at 0.43 h (t_max), and the absolute bioavailability (F) was 88.81%; and for the oral route the same parameters were 0.66 ± 0.15 μg/mL, 1.54 ± 0.27 h and 74.42%. A multiple‐peak phenomenon was present after oral administration. The plasma profile of valnemulin exhibited a secondary peak during 2–6 h and a tertiary peak at 32 h. The favorable PK behavior, such as the wide distribution, slow elimination and acceptable bioavailability indicated that it is likely to be effective in chickens.     

DNA Methylation Pattern in Pronuclear-Stage Mouse Embryos: Effect of Oocyte Vitrification

This study was conducted to investigate the pattern of DNA methylation in pronuclearstage mouse embryos derived from vitrified-warmed oocytes.Mouse oocytes at metaphase Ⅱ (MⅡ) stage of meiosis were all...