Effect of dietary n-6-to-n-3 fatty acid ratio on complete blood and total white blood cell counts, and T-cell subpopulations in aged dogs

OBJECTIVE: To determine effect of diets with variable n-6-to-n-3 fatty acid (FA) ratio on CD4+ and CD8+ T-lymphocyte subpopulations, and on results of routine laboratory analyses (CBC and total WBC count, serum biochemical analyses, and urinalysis). ANIMALS: 20 healthy, aged (9.5 to 11.5 years old) female Beagles. PROCEDURE: Dogs were fed 1 of 3 diets that contained 6% fat by weight but differed in amounts of n-6 and n-3 FA. For 11 weeks, 6 dogs were fed a low concentration of n-3 FA (ratio, 31:1), 7 were fed a medium concentration (5.4:1), and 7 were fed a high concentration (1.4:1). Preprandial blood and urine samples were collected before beginning the study and at 8 weeks for evaluation of laboratory variables. Before and at 3, 6, and 8 weeks during the study, blood was drawn for total WBC and lymphocyte counts and for characterization of T-cell subpopulations. At 8 and 10 weeks, dogs were vaccinated with keyhole limpet hemocyanin suspension. Blood was drawn 4 days after each vaccination, and lymphocytes were isolated for flow cytometry. Effects of diet and vaccination on each variable were determined. RESULTS: After vaccination, total lymphocyte count increased and CD4+ T lymphocyte count and the CD4(+)-to-CD8+ ratio decreased in dogs consuming the diet with n-6-to-n-3 FA ratio of 1.4:1. CONCLUSION: Feeding a diet with n-6-to-n-3 FA ratio of 1.4:1 had significant effects on CD4+ T lymphocytes in healthy, aged Beagles after vaccination.     

鸡新城疫病毒地方株的分离鉴定及其遗传变异分析

从河北省保定地区发病鸡群中分离到2个具有血凝性的病毒株分别命名为HBA和HBB,其血凝作用可被NDV阳性血清抑制,而不能被AIV(H9亚型)、EDS76阳性血清抑制,表明2个分离株均为新城疫病毒。通过测定MDT、ICPI和IVPI等方法鉴定分离株的毒力符合强毒标准。利用RT-PCR技术成功扩增了2株分离株的F基因片段(约540bp),通过测序及遗传变异分析表明两毒株之间的核苷酸同源性为87.7%,氨基酸同源性为91.6%,结合系统发育进化树分析表明HBA为基因Ⅵ型,HBB为基因Ⅶ型。     

金水乌鸡黑羽丝毛系选育报告

用黑羽黑皮的江汉鸡对白羽丝毛乌骨鸡先导入杂交后闭锁群继代选育,培育出金水乌鸡黑羽丝毛系.黑羽丝毛系90日龄体重1kg以上,料肉比3.36:1.     

中草药复合添加剂防治兔球虫病及增重效果研究

选用无感染幼兔４２只,随机分为Ａ、Ｂ、Ｃ、Ｄ、Ｅ５组,进行防治兔球虫病和增重试验,其中Ａ组为中药加矿微加喹乙醇组,Ｂ组为中药加矿微组,Ｃ组为西药对比组,Ｄ组为感染不给药组,Ｅ组为不感染不给药组;在同样饲料、同等饲养条件下,饲养３０天。结果,Ａ组保护率９０％,增重率９８．２％;Ｂ组保护率１００％,增重率１３２．１％;Ｃ组保护率９０％,增重率７６．６％;Ｄ组兔于第１１天全部死亡;Ｅ组保护率１００％,增重率９６．２％。试验结果证明,保护率以纯中药Ｂ组最佳,Ａ组次之,增重率Ａ、Ｂ组均高于Ｃ组和Ｅ组,以Ｂ组最佳。     

多菌灵及漂白粉液处理桑叶对原蚕卵及杂交后代的影响

研究了用多菌灵及漂白粉液消毒过的桑叶饲养育原蚕对其产卵及后代杂种的影响。结果表明：能有效防止家蚕微粒子的食下传染，对原蚕的生长发育、健康性、产卵等均无不良影响；对杂种后代的生长发育、生产性能及茧丝质也不无不良影响。多菌灵的控微效果与桑叶全程浸消的效果基本一致，但其操作比桑叶全程浸消简单、省时、省力。     

围产期奶牛免疫抑制发生原因及其缓解的营养对策

奶牛围产期一般是指产前3周至产后3周这一时期,此时奶牛生理、代谢和免疫功能发生显著变化,会出现不同程度的免疫抑制现象。由于免疫功能下降,此时也是传染病的高发期,严重影响奶牛健康,进而导致产后牛奶品质下降。因此,如何缓解围产期奶牛免疫抑制状态,降低产后的发病率,已成为目前研究的一个热点。本文综述了围产期奶牛发生免疫抑制的原因及用于缓解的营养对策。     

基于MSP430F149芯片的便携式发动机窜气量测量仪的研制

介绍了在不解体车用发动机的情况下,通过测试曲轴箱窜气量的大小,即可检测活塞环与气缸壁的磨损程度的一种专用检测仪器,并以EQ6100发动机的结构特点为例,设计了专用测试用传感器,测出了其特性曲线,用低功耗单片机MSP430作为微控制器核心,构造了该测量仪器。测试结果表明:该仪器抗扰能力强,测试精度高,测试简单、方便,为发动机故障诊断提供了依据,用户可把仪器的结构、参数稍加改动即可应用于其它类型发动机的不解体故障诊断,具有一定的通用性。     

Relationship between stable carbon isotope discrimination and water use efficiency under regulated deficit irrigation of pear-jujube tree

To investigate the relationship between stable carbon isotope discrimination (Δ) of different organs and water use efficiency (WUE) under different water deficit levels, severe, moderate and low water deficit levels were treated at bud burst to leafing, flowering to fruit set, fruit growth and fruit maturation stages of field grown pear-jujube tree, and leaf stable carbon isotope discrimination (Δ_L) at different growth stages and fruit stable carbon isotope discrimination (Δ_F) at fruit maturation stage were measured. The results indicated that water deficit had significant effect on Δ_L at different growth stages and Δ_F at fruit maturation stage. As compared with full irrigation, the average Δ_L at different growth stages and Δ_F at fruit maturation stage were decreased by 1.23% and 2.67% for different water deficit levels, respectively. Δ_L and Δ_F among different water deficit treatments had significant difference at the same growth stage (P < 0.05). Under different water deficit conditions, significant relationships between the Δ_L and WUE_i (photosynthesis rate/transpiration rate, P_n/T_r), WUE_n (photosynthesis rate/stomatal conductance of CO_2, P_n/g_s), WUE_y (yield/crop water consumption, Y/ET_c) and yield, or between the Δ_F and WUE_y and yield were found, respectively. There were significantly negative correlations of Δ_L with WUE_i, WUE_n, WUE_y and yield (P < 0.01) at the fruit maturation stage, or Δ_L with WUE_i and WUE_n (P < 0.01) over whole growth stage, respectively. Δ_F was negatively correlated with WUE_y, WUE_n and yield (P < 0.05), but positively correlated with ET_c (P < 0.01) over the whole growth stage. Thus Δ_L or Δ_F can compare WUE_n and WUE_y, so the stable carbon isotope discrimination method can be applied to evaluate the water use efficiency of pear-jujube tree under the regulated deficit irrigation.     

导致牛繁殖障碍的遗传因素及其分析

繁殖障碍的发生几乎都是遗传与环境因素相互作用的结果,因而育种方法有助于减少各种繁殖障碍的蔓延,并且随着牛生产性状遗传进展的累积,必须将在经济重要性方面不低于产肉、产奶等性状的繁殖障碍纳入育种计划中。本文以上述观点为基点,综述了牛的繁殖障碍的遗传性影响因素,介绍了繁殖障碍的几种遗传学分析方法,阐述了控制遗传性繁殖障碍的4项育种措施,提议以寻求适当的标记性状作为繁殖障碍遗传流行病学研究和临床诊断指标的突破口。     

Survey on the contamination of Toxoplasma gondii oocysts in the soil of public parks of Wuhan, China

Toxoplasma gondii of warm-blooded animals and humans is an important pathogenic agent throughout the world. Soil is increasingly recognized as an important source in the transmission of Toxoplasma. To attain the contamination status of T. gondii in the soil of public parks, a total of 252 soil samples were collected from September 2009 to August 2010 at different sites located in 6 public parks of Wuhan, Hubei, China and detected by PCR and loop-mediated isothermal amplification (LAMP). The detection limit of PCR/B1, PCR/529 and LAMP was determined to be 50, 5, and 5 tachyzoites in soil, respectively. Forty-one samples were found positive for Toxoplasma DNA by PCR on both genes, whereas LAMP products were generated in 58 samples (χ(2)=3.6328, P=0.0567). All parks were found contaminated and no significant difference was found among the parks (PCR: χ(2)=0.0072, P=0.9325; LAMP: χ(2)=0.6101, P=0.4347). However, contamination was found with significantly different among the four seasons (PCR: χ(2)=11.6066, P=0.0007; LAMP: χ(2)=12.4636, P=0.0004), with a gradual decrease in the prevalence from spring to winter on both analyses. This is the first investigation on soil contamination of public parks in China by T. gondii oocysts. The results indicate that the soil of public parks contaminated with T. gondii oocysts may play a role in the epidemiology of toxoplasmosis and effective preventive measures should be considered. Moreover, the conventional PCR and LAMP used in the present study are applicable to detect T. gondii oocysts in soil samples.