液相色谱-串联质谱法同时检测鸡肉中61种抗菌药物

为建立固相萃取结合液相色谱-串联质谱同时测定鸡肉中磺胺类、喹诺酮类、大环内酯类药物残留的分析方法,通过准确称取2 g鸡肉样品,经PBS缓冲液提取,以Agilent Pleax PCX固相萃取柱净化,最后以液相色谱-串联质谱进行检测.结果显示:在最优试验条件下测得磺胺类、喹诺酮类、大环内酯类抗菌药物线性良好,相关系数(R...     

Application of non-structural protein ELISA kits in nationwide FMD surveillance in pigs to demonstrate virus circulation in Taiwan

Large scale surveillance of FMD non-structural protein (NSP) antibody in pigs was conducted to monitor for FMD virus circulation in Taiwan using Ceditest and UBI NSP ELISA kits after recurrence of FMD in 2009. A total of 53,759 serum samples were collected from pigs in the auction markets in 2009. There were 43 farms with positive FMD NSP reactors to both NSP ELISA tests in the nationwide surveillance. After tracing back, clinical examination and the NSP ELISA testing using both Ceditest and UBI on 14 follow-up serum samples from all the herds with confirmed NSP reactors in 2009, there were 4 farms classified as positive on follow-up testing criteria. In this surveillance, we have demonstrated that the NSP ELISA tests of outbreak farms followed by clinical and serological investigation could be used to detect FMD circulation in the pig population in Taiwan even while the national compulsory vaccination program is ongoing.     

白羽肉鸡球虫病的诊断与防治

球虫病是集约化养鸡场中常见的危害较大的一种原虫病,它以消瘦、贫血、血性下痢、发病率及死亡率高为特征。2010年6月10日河北省承德市宽城县一家养鸡场饲养的白羽肉鸡发生此病。我校教学兽医院接诊后经过流行病学调查、临床症状观察、病理剖检及涂片镜检等确诊为球虫病。根据情况立即采取了综合性的防治措施,使病情得到了有效控制。     

猪链球菌2型诊断与防制措施

<正>猪链球菌(Streptococcus suistype 2,SS2)已经成为危害养猪生产及人类健康的重要人畜共患病。可引起猪脑膜炎、关节炎、心内膜炎及猝死等;致人败血症、心内膜炎、脑膜炎,严重的致人链球菌毒素休克综合征而死亡。1998年7月江苏南通某地猪群暴发猪链球菌2型,同时导致21     

紫苏-月苋草复合提取物对肉种鸡生产性能的影响

试验选用1日龄AA肉用种鸡17000羽,随机分成对照组(饲喂基础日粮)和试验组(在基础日粮中添加0.25g/kg紫苏-月苋草复合提取物),研究紫苏-月苋草复合提取物对肉种鸡生产性能和繁殖性能的影响。试验结果表明:添加该复合提取物后,试验鸡育成期体重、均匀度显著提高,死淘率降低,产蛋率和平均蛋重有较大的提高,受精率和入孵蛋健雏率分别提高1.04个百分点和5.35个百分点。     

L-arginine prevents reduced expression of endothelial nitric oxide synthase (NOS) in pulmonary arterioles of broilers exposed to cool temperatures

This study investigated nitric oxide synthase (NOS) expression in the endothelium of pulmonary arterioles of broilers during the development of pulmonary hypertension syndrome (PHS). PHS was triggered by exposing broilers to sub-thermoneutral (cool) temperatures and an additional 1.0% L-arginine was added to the basal diet to evaluate the effects of supplemental L-arginine on nitric oxide (NO) production, endothelial NOS expression, and the incidence of PHS. Cumulative mortality from PHS, right/total ventricle weight ratios (RV/TV), and body weights were recorded. Plasma NO concentration and NOS expression in the endothelium of pulmonary arterioles with an outer diameter ranging from 100 to 200 microm were determined. Birds exposed to cool temperatures had increased pulmonary hypertension and PHS mortality and diminished endothelial NOS expression. Supplemental dietary L-arginine reduced PHS mortality and elicited higher NOS expression within the pulmonary endothelium coincident with elevated NO production. The results demonstrated that broilers developing PHS exhibited diminished NOS expression in the endothelium of their pulmonary arterioles. Supplemental L-arginine prevented the reduced expression of NOS in the pulmonary endothelium, which might contribute to the increased production of NO by the pulmonary vasculature.     

Inhibition of porcine circovirus type 1 and type 2 production in PK-15 cells by small interfering RNAs targeting the Rep gene

Porcine circovirus type 1 (PCV1) and type 2 (PCV2) are two genotypes of porcine circovirus. Both of them are presumed to be widespread in the swine population. Currently, there is no specific treatment for their infections. RNA interference (RNAi) is a sequence-specific RNA degradation mechanism mediated by small interfering RNA (siRNA), which represents a possible therapeutic application for the treatment of viral infections. In this study, three siRNA expression plasmids (pS-RepA, pS-RepB and pS-RepC) were generated to target three different coding regions of the Rep protein (Rep) of PCV. These siRNAs were used to inhibit PCV production in a porcine kidney cell line, PK-15 cells. Our results revealed that Rep gene expression was inhibited by pS-RepA, pS-RepB and pS-RepC to different degrees. Moreover, our study also showed that the production of PCV1 and PCV2 was reduced by these siRNAs. pS-RepC, which targets the middle region of Rep gene, proved to be the most efficient siRNA for inhibition of Rep expression and viral production. Taken together, our data suggest that RNAi could be investigated as a potential treatment for PCV infection.     

秋蚕饲育技术要点

针对秋季气候环境条件,采取相应的技术措施,才能保证秋蚕稳产高产. 1 把好消毒关 在夏蚕饲养结束后,首先进行蚕后消毒,即用2%的福尔马林液或含有效氯1%的漂白粉澄清液将蚕室蚕具先消一次毒后再搬出去清洗,晒干.养蚕前又用含有效氯1%漂白粉液对蚕室蚕具进行消毒,然后用硫磺柏桠熏烟一次,最后开放门窗,准备养蚕.上一季养蚕的大蚕室和上蔟室不能用来养下一季的小蚕.在饲养中要做到蚕期继续消毒,坚持每天用漂白粉防僵粉或新鲜石灰进行蚕体蚕座消毒,如发现病蚕应及时隔离淘汰,除沙时,对死蚕和淘汰的病、弱蚕必须投入石灰缸中集中深埋.除沙后坚持换鞋进出贮桑室,坚持洗手给桑等卫生制度,隔离病源防止蚕病传播蔓延.小蚕期坚持用含有效氯0.3%的漂白粉液进行擦洗桑叶,稍干后再喂蚕.     

控光增绒技术在辽宁绒山羊中应用效果观察

2010～2012年,辽宁省畜牧科学研究院先后在本院科技示范场、凤城市绒山羊养殖户,开展了辽宁绒山羊控光增绒试验,设置了不同控光时间的试验组以及相应的对照组,以期验证该项技术在辽宁地区和辽宁绒山羊生产中的应用效果。试验结果表明,该项技术对辽宁绒山羊增绒效果不明显,达不到一年两次剪绒、提高产绒量的目的,建议谨慎将该项技术应用于辽宁地区辽宁绒山羊生产中。     

不同投喂方式对革胡子鲶消化酶的影响

在（25±1）℃水温、自然光照条件下,设3种投喂方式饲养革胡子鲶（clarias leath-er）：第1种连续投喂整个试验期间不间断,第2和3种分别连续投喂3、7 d 后饥饿1 d,3种方式分别以R0（对照组）、R1/3、R1/7表示,试验周期共45 d。结果显示：R0、R1/3和R1/7组胃、后肠和肝脏中蛋白酶活性影响差异不显著,但前肠和中肠内蛋白酶活性影响存在差异(P<0.05)。R0、R1/3、R1/7组的胃、前肠、中肠、后肠和肝脏中淀粉酶影响不显著,R0、R1/3、R1/7的胃、前肠和肝脏内脂肪酶活性影响差异显著(P<0.05),而R0、R1/3、R1/7组中肠和后肠中脂肪酶活性影响差异不显著(P>0.05)。