Study on the abuse of amantadine in tissues of broiler chickens by HPLC‐MS/MS

To evaluate the residual target tissues for better monitoring of amantadine abuse in broiler chickens, 22‐day‐old commercial Arbor Acres broiler chickens were, respectively, fed with 10, 20, and 40 mg/kg of amantadine for five consecutive days. Plasma, breast, and liver tissue samples from the chickens were collected 0, 4, 16, 24, 48, 96, 144, and 312 h after amantadine withdrawal. The high‐performance liquid chromatography–tandem mass spectrometry method was used to detect the concentrations of amantadine. The highest concentration was found in the chicken liver and it took the longest time for amantadine to vanish by metabolism. In the high‐dose group, amantadine residues were still detected 312 h after amantadine withdrawal. As the amantadine dose increased, amantadine residues in the chicken liver were more slowly to disappear than in other tissues. Even if approximately the same concentration of amantadine residues was found in chicken breast and plasma samples, it took a shorter time before the residues were eliminated. In the medium‐ and high‐dose groups, the concentrations of amantadine residues in chicken liver samples were substantially higher than those in chicken breast and plasma samples, and it took more time to eliminate them. Therefore, the chicken liver can be used as a target tissue to detect illegal use of amantadine.     

Effects of dietary protein and growth hormone-releasing peptide (GHRP-2) on plasma IGF-1 and IGFBPs in Holstein steers

This study was conduct to determine the influence of dietary protein on the response of plasma insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding proteins (IGFBPs) to exogenous growth hormone releasing peptide-2 (GHRP-2 or KP 102) in Holstein steers. Eight 16-month-old Holstein steers were grouped by liveweight to two feeding treatments; high protein (HP; CP 1.38 kg/day and TDN 4.5 kg/day DM intake, n=4) or low protein (LP; CP 0.66 kg/day and TDN 4.42 kg/day DM intake, n=4). The experiment was a single reverse design whereby each group was injected twice daily with GHRP-2 (12.5 microg/kg body weight (BW)/day) or saline solution into the jugular vein for a 6-day period. Plasma IGF-1 in the HP group were higher than in the LP group (P<0.05), but plasma 34 kDa IGFBP-2 was lower in the HP than the LP group (P<0.05). The amplitude of the maximum growth hormone (GH) peaks responding to GHRP-2 injection were higher at day 1 than at day 6 of saline or GHRP-2 treatment in both LP and HP steers (P<0.05). The area under the GH response curve for 180 min after the GHRP-2 injection was not significantly different between the LP and the HP groups at days 1 and 6. A response in plasma IGF-1 concentration to GHRP-2 treatment in the HP group was observed at day 1 (198.9+/-18.1 ng/ml), day 2 (195.2+/-21.1 ng/ml) and day 6 (201.3+/-14.8 ng/ml) (P<0.05). No increase in plasma IGF-1 was observed from GHRP-2 administration in the LP group. Although the response of plasma IGF-1 concentration to GHRP-2 administration was increased in the HP group (P<0.05), there was no apparent effect of GHRP-2 treatment on plasma 38-43 kDa IGFBP-3 and 34 kDa IGFBP-2 at days 2 and 6 of treatment. In conclusion, it is proposed that the 34 kDa IGFBP-2 is sensitive to dietary protein level and may play an important role in the regulation of circulating IGF-1 in ruminant. In addition, increased plasma IGF-1 concentration observed in the HP group in response to the GHRP-2 treatment did not appear to affect plasma IGFBPs.     

水稻和陆稻品种抗旱性综合评价

从产量性状、外部形态和生理生化3个方面多个指标中选出11项有代表性的指标,采用其旱/水比相对值（划分评分标准）和权重计分法对4个水、陆稻品种（组合）进行了抗旱性综合评价,综合评分以TANGARA最高（4.06分）明显高于其他3个品种,IAPAR9（3.33分）次之,稍高于新香优80（3.21分）,R80最低（2.59分）。表明TANGARA有较强的抗旱性,IAPAR9和新香优80抗旱性相差不大,R80较差,与生产实际表现基本一致。表明此项方法具有较强的客观性和准确性。     

2018年国内外蜂王浆研究概况

本文对2018年国内外蜂王浆研究概况进行了综述,对公开发表的65篇中英文文献及专利的地域分布和研究领域进行了统计分析和评述,并重点介绍了蜂王浆在化学组分、质量控制、生物学活性等领域的研究新进展。与2017年相比,2018年蜂王浆的研究热度回升,成果丰硕。     

黄鳝烂尾病病原的研究

从发病黄鳝的病灶部位分离到 HS1 菌株。用 HS1 菌株人工感染体重 2 0～ 30 g的黄鳝 ,感染的黄鳝出现与自然发病黄鳝相似的症状 ,并从感染黄鳝的病灶中分离到与原菌株相同的细菌 ,证实 HS1 菌株是引起黄鳝烂尾病的病原。经细菌的形态、培养及生理生化特性测定 ,HS1 菌株鉴定为产碱假单胞菌 ( Pseudomonasalcaligenes) ,并进行了药敏试验     

小山村 大事业

这篇文章的主角是浙江花园生物高科股份有限公司（以下简称“花园高科”）. 这是一个从浙中山村（浙江东阳花园村）走出来的企业,这是一家国家级高新技术企业,其维生素D3项目被列为“国家高技术产业化示范工程项目”和国家“双高一优”项目.[编者按]     

一种优化鸡胚成纤维细胞制备方法及生长曲线测定

鸡胚成纤维细胞（CEF）的来源方便,制备简单,耐受性好,且适合于许多病毒的生长繁殖,因此被广泛用于疫苗的生产、病毒的培养以及一些细胞和分子生物学的研究。然而传统的鸡胚成纤维细胞制备方法存在制备时间长、死细胞较多和细胞贴壁慢的问题。笔者根据经验摸索出一种实验室快速制备CEF的简便方法,并通过台盼蓝染色用细胞计数法绘制了原代CEF及次代CEF的生长曲线。该简便方法的建立为实验室快速制备高质量高纯度的鸡胚成纤维细胞提供了方便,同时对其生长曲线的测定也为进行基因转染方面的研究积累了资料。     

强化兽药GSP后续监管 保障兽药产品质量安全

随着兽药GSP认证工作的全面结束,兽药GSP的日常监管工作越来越凸显其重要性。本文综合论述了在兽药GSP日常监管过程中发现的诸多问题,以及今后如何做好兽药GSP后续监管工作所采取的措施。     

紫穗槐幼苗不同生长阶段叶水势对干旱胁迫与复水的响应特征

为揭示紫穗槐（Amorpha fruticosa）幼苗叶水势对土壤干旱与复水环境的响应特征,本研究通过盆栽试验,研究了土壤干旱胁迫及复水对紫穗槐幼苗不同生长阶段叶水势的影响。结果表明：土壤水分、干旱历时和生长阶段3个因素以及各因素间的相互作用对紫穗槐幼苗叶水势均有极显著影响（P<0.01）;随着干旱程度加剧,幼苗叶水势呈下降趋势,水分胁迫指数呈上升趋势;40.00%土壤相对含水量下的幼苗叶水势下降幅度达到最大,其中干旱15 d的生长初期和生长中期以及干旱30 d的生长后期的叶水势分别比对照下降了0.71 MPa,1.12 MPa和0.58 MPa;复水后,叶水势出现补偿效应,随着复水后时间的延长,幼苗3个生长阶段叶水势逐渐恢复,恢复速率与干旱程度、干旱历时和生长阶段密切相关,但均在复水72小时后恢复到接近对照水平。