Effects of dietary supplementation of Haematococcus pluvialis powder on gonadal development,coloration and antioxidant capacity of adult male Chinese mitten crab (Eriocheir sinensis)

The green algae Haematococcus pluvialis is an important source of natural astaxanthin as feed additive. This study was conducted to investigate the effects of dietary supplementation of H. pluvialis powder on gonadal development, coloration and antioxidant capacity of adult male Chinese mitten crab Eriocheir sinensis, and four experimental diets were formulated to contain 0, 0.2%, 0.4% and 0.6% of H. pluvialis powder. There were four treatments (defined as D1~D4) in this study and each treatment had three replicates. Dietary H. pluvialis contents had no significant effects on survival, body weight gain rate and gonadal development of male E. sinensis. For colour parameters, the total carotenoids content in carapace and hepatopancreas as well as hepatopancreatic lightness (L*) and carapace redness (a*) increased significantly with increasing dietary H. pluvialis (p < 0.05). For the antioxidant indices in the serum, D4 had the lowest activities of superoxide dismutase (SOD) and peroxidase (POD), but the highest glutathione peroxidase (GSH‐Px) and lactic dehydrogenase (LDH), while the malondialdehyde (MDA) in serum and hepatopancreas decreased significantly with the rising content of dietary H. pluvialis (p < 0.05); D1 had the highest levels of SOD, POD and GSH‐Px in hepatopancreas. For the non‐specific immune indices, the highest activities of acid phosphatase (ACP) and γ‐glutamyl transpeptidase (γ‐GT) were found on the serum of D3 and D4 (p < 0.05). D1 had the highest levels of ACP and alkaline phosphatase (ALP) in hepatopancreas, while D2 and D3 had the lowest levels of ALP and ACP respectively. These results suggested the optimal dietary natural astaxanthin level was around 40 mg/kg diets.     

Immunoadjuvant activities of a recombinant chicken IL-12 in chickens vaccinated with Newcastle disease virus recombinant HN protein

Recombinant fowlpox virus (rFPV/HN) expressing Newcastle disease virus (NDV) HN gene and rFPV/HN/chIL-12 co-expressing chicken IL-12 (chIL-12) and HN (rHN/chIL-12) genes have been characterized. rHN/chIL-12 or rchIL-12, expressed by our previous construct rFPV/chIL-12, co-administered with rHN was assessed for adjuvant activities of chIL-12. Chickens were vaccinated with various amounts of rHN/chIL-12 mixed with mineral oil (MO), intramuscularly. Levels of hemagglutination-inhibition (HI) antibody production depended on the concentration of the injected rHN or rHN/chIL-12. The lower HI antibody titers were obtained in chicken groups rHN/chIL-12/7-rHN/chIL-12/9, receiving 60ng rHN/8ng chIL-12 with MO, 30ng rHN/4ng chIL-12 with MO or 15ng rHN/2ng chIL-12 with MO, respectively, compared to those in chicken groups rHN/7-rHN/9, receiving rHN with MO alone. However, chickens in group rHN/chIL-12/7 or rHN/chIL-12/8 and rHN with MO alone showed the same effective protection. Chicken group rHN/chIL-12/9 was even more protective than that in group rHN/9. When rchIL-12 was co-injected with 15ng rHN plus MO, chickens produced low levels of HI antibody titers; while higher levels of IFN-γ production and an effective protection rate (83%) were obtained. On the other hand, low levels of IFN-γ production and low protection response (50%) were obtained in chickens injected with rHN with MO alone. Taken together, when the concentration of rHN decreased to certain levels, rchIL-12 reduced HI antibody production. The increase in the induction of IFN-γ production might suggest the enhancement of the cell-mediated immunity which conferred the protection from the NDV challenge.     

菜粉蝶颗粒体病毒DNA限制性内切酶图谱分析

采用“酶-SDS-酚”法提取的菜粉蝶(Pieris rapae)颗粒体病毒京农801株(PrGV-JN801)DNA,A260/A280=1.85,经琼脂糖凝胶电泳呈现一条带。三种限制性内切酶消化PrGV-JN 801 DNA,其结果分别为:Hind Ⅱ,12个片段;EcoR Ⅰ,15个片段;Bam HI,12个片段。三种酶切所得限制性片段累加分子量的平均值75.04×10~6道尔顿为PrGV-JN 801DNA的分子量。     

黄土高原人工草地的土壤水分动态及水土保持效益研究

通过９年观测，黄土高原人工草地土壤水分的季节性变化可划分为三个阶段，在此基础上模拟不同人工草地土壤水分的变化规律；随着牧草生育期的延长至第９年，人工草地土壤水分恢复程度逐渐减弱；沙打旺生存能力极强，能够高效地利用深层土壤贮水；用数学模型可以模拟不同人工草地的水土流失，将植被因子引入水土流失方程，可以定量描述对水土流失的影响；反映植被、土壤等因子与水土流失关系的复合因子Ａ￣１值，基本上代表不同人工草地水土流失状况。     

病害动物及其产品无害化处理程序探讨

动物检疫员在产地检疫、屠宰检疫环节中．动物防疫监督人员在日常监督检查中，经常会发现病害动物、动物产品，相当多的检疫监督人员在对病害动物、动物产品进行无害化处理时，不出具任何文书，直接进行无害化处理．事后甚至没有记录，在病害动物、动物产品无害化处理程序上存在很多问题，如果货主提起行政诉讼，那动物防疫监督机构就面临着败诉的危险．笔者现就病害动物、动物产品无害化处理程序谈谈自己的看法。     

柑桔脚腐病研究

 本研究证明Phytophthora parasitica是我国柑桔脚腐病病原菌之一;高温多雨有利本病盛发;据对51个柑桔种质资源抗病性测定结果表明:枳、枳橙、枳柚、大叶金豆、酸橙等19个种类或品种对本病具有高抗或抗病,福桔、尤力克柠檬等14种材料为感病或重感病型,其余18个为中抗或中感型;防治试验证明,瑞毒霉(metalaxyl)、乙磷铝(phosethyl-Al)、甲霜铝铜(①metalaxyl②aluminum tris)等杀菌剂对病树有明显的治疗作用。利用抗病砧木靠接对缓解该病危害具有事半功倍的效果。     

Ultrastructural pathogenesis of the PRRS virus

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) was first isolated in swine alveolar macrophages (SAMs) and has subsequently been reported to replicate in other cell lines. Entry of the virus inside the cell takes place by receptor-mediated endocytosis. Following the entry of the virus into the cell, several not completely understood changes take place. PRRSV has been reported to be an apoptotic-inductor virus both in vivo and in vitro. Interestingly, it has been suggested that PRRSV-induced apoptosis occurs in cells other than those in which PRRSV replicates by a bystander mechanism. In this paper the ultrastructural pathogenesis of PRRSV will be reviewed.     

论省级饲料兽药实验室的管理

我站是重庆市农业局直属处级行政执行型全额拨款事业单位。现有技术人员43名,其中高级职称13名,中级5名,硕士11名,本科生17名,专科11名,其他4名。实验室现有面积3250m2,拥有细菌鉴定及药敏测试仪、气-质联用仪、高效液相色谱仪、气相色谱仪、电感耦合等离子体原子发射光谱仪(ICP)等199台(套)精密仪器,价值2000余万元。能承担现有国家标准、行业标准和重庆市地方标准规定的所有动物疫病诊断,饲料、兽药、畜产品质量检测检验项目。检测指标达到微量级,有的指标甚至可以检测痕量级。实验室已经全面通过重庆市质量技术监督局计量认证和农业部…     

家畜胚胎性别鉴定的研究进展

家畜胚胎性别鉴定是家畜胚胎移植的重要内容，对实现动物性别的人为控制具有重要意义。近年来，随着性别鉴定技术的不断发展，动物性别控制主要采用两条途径，即X精子与Y精子的分离和胚胎性别的鉴定。在前者尚未取得完全成功的情况下，胚胎的性别鉴定已成为性别控制的主要途径。家畜胚胎的性别鉴定技术是家畜胚胎移植技术的一项重要内容。通过移植已知性别的胚胎，控制家畜后代的性别比例，能加快优良母畜的繁殖进程，促进高效畜牧业的发展。     

人类活动对晋西北地区生态环境影响的初步研究

晋西北地处我国北方生态环境脆弱的农牧交错带,同时又是资源富集,资源与环境的矛盾十分突出。人类不合理的经济活动加剧了该区以土壤风蚀沙化和水土流失为主的环境退化问题。因此,加强环境保护刻不容缓。