Effect of copper edetate injection in dry pregnant cows on hematology,blood metabolites,weight gain and health of calves

The objectives of the present study was to investigate the effects of the copper injection and injection timing to pregnant dairy cows at dry period on the hematology, some serum metabolites, health and growth of their calves. Thirty Holstein cows at the dry period were assigned to the three following experimental groups: 1) control (injections of 2.5 ml normal saline), 2) test 1 (125 mg Cu as copper edetate injection at the first week of the dry period) and 3) test 2 (125 mg Cu as copper edetate injection at the third week of the dry period). Ten milliliters of jugular blood was taken from all calves 24–48 h after birth and at 7, 14, 21 and 28 days of age for measuring hematological and biochemical parameters. For evaluation of growth and health, body weight of all of the calves was measured at birth and at the end of the trial, and the health of calves was checked by a technician twice a day and any sign of illness, treatment (if needed) and duration of illness was recorded. Copper treatment was proved to have a significant effect on the counts of WBC (lower in test 2, higher in test 1), lymphocyte (lower in test 2, higher in test 1) and the concentrations of fibrinogen (lower in test 1, higher in test 2), cholesterol (lower in control, higher in test 1) and copper (lower in test 1, higher in test 2) (p < 0.05). Age (sampling time) also influenced most measured parameters (p < 0.05) except values of WBC, neutrophil, monocyte, globulin and concentrations of iron, zinc and copper.     

植物乳杆菌ST-Ⅲ脱脂乳的发酵工艺优化

为研发富含植物乳杆菌ST-Ⅲ新型益生菌发酵乳制品,该试验尝试用植物乳杆菌ST-Ⅲ和嗜热链球菌共发酵,并对植物乳杆菌ST-Ⅲ发酵乳的工艺进行了优化研究。通过单因素试验分析了大豆多肽添加量、葡萄糖酸锰添加量、嗜热链球菌的接种量和发酵温度对发酵乳的pH值和植物乳杆菌ST-Ⅲ活菌数的影响。通过响应面法优化并确定了最佳工艺条件:大豆多肽添加质量分数11 g/kg;葡萄糖酸锰添加质量分数11 mg/kg;嗜热链球菌的接种量106 CFU/g;植物乳杆菌ST-Ⅲ的接种量106 CFU/g;发酵温度为37℃。在此优化最佳工艺条件下,发酵乳的植物乳杆菌ST-Ⅲ的活菌数为1.88×109 CFU/mL,有效地提高了发酵乳中植物乳杆菌ST-Ⅲ的活菌数。研究结果可为拓展植物乳杆菌ST-Ⅲ在乳制品领域的应用提供参考。     

京津地区夏季着装行为对办公建筑空调能耗的影响

着装行为通过影响室内空气参数的设定而影响建筑空调能耗。利用能耗模拟软件DeST,计算出该地区典型着装行为下实测运行参数与期望参数对应的建筑空调能耗比推荐标准下能耗分别降低了10.86%和13.16%。而基于典型着装行为的实验热学性能参数下,平均只降低4%,说明由着装热阻关联的主观温度需要按地区着装行为进行修正。提出了控制建筑空调能耗的着装行为调节模型,着装行为节能率ε_c为负值时节能,为正值时不节能。京津地区办公建筑节能率为0的临界服装热阻为0.563 clo,空调系统设计和运行节能的前提是,着装热阻低于临界值。着装行为调节模型为地区着装形式和着装面料提供了量化标准,为精确控制建筑能耗提供了一种方法。     

小麦抗病基因同源序列(RGAs)的克隆与分析

RGA(抗性基因同源序列)法是克隆植物抗性基因的一种经济有效的方法,成为近年来的研究热点。本实验综合分析了拟南芥,西红柿,水稻,烟草等植物已克隆的抗性基因,并以这些抗性基因的NBS(核酸结合位点),LRR(富含亮氨酸重复),STK(丝氨酸/苏氨酸激酶)保守结构域设计并合成了几十对RGA引物,对小麦抗条锈病材料进行PCR扩增,获得以Xal-NBS为引物的R88RGA片段,经克隆和序列比对分析,发现该片段与逆境条件下植物抗病信号传导相关,与蛋白激酶同源性达到96%。此项研究对抗病机理的研究和基因的发掘有重要的指导意义。     

Veneer strand flanged I-beam with medium density fiberboard or particleboard as web material I: the forming method and fundamental properties

I-beams flanged with veneer strands with medium density fiberboard (MDF) or particleboard as web material were produced by hot pressing. The forming and pressing method used a special metallic mould that allowed flanges to be formed and bonded to the web at the same time. Many I-beams were able to be produced in a single hot pressing cycle and this method allows the utilization of residues and wastes from wood and wood-composite industries. The forming and pressing method was found to be technically suitable for the production of such I-beams. The fundamental properties of the specimens produced were assessed and the results indicated that the I-beams had promising mechanical properties; for example, the modulus of rupture ranged from 40 to 56MPa depending on the flange density. The bond quality between the web and flange was found to have a critical effect on the strength of the entire I-beam. The I-beams were found to have relatively high bond strengths between the web and flange, ranging from 3.3 to 5.0MPa in the parallel direction. The dimensional stability of the I-beams was found to be excellent in the thickness direction of the beam, but not in the compression (width) direction.Part of this paper was presented at the 53rd Annual Meeting of the Japan Wood Research Society in Fukuoka, March 2003     

Seroprevalence of camel brucellosis (Camelus dromedarius) in Somaliland

The present study was delineated to investigate the prevalence and risk factors of camel brucellosis in Northern Somalia (Somaliland). The study was carried out at three main districts of camel-rearing regions of Somaliland (Awdal, Waqoyi Galbed and Togdheer) in the period from July to November, 2008. A total of 1246 camel blood sera were randomly collected from 42 sporadic small scale camel herds. Two serological tests were used to screen all serum samples, Rose Bengal Plate Test (RBPT) and indirect ELISA (I-ELISA). Multivariate logistic regression was constructed to study the risk factors associated with Brucella seropositive cases. The overall prevalence of camel brucellosis in districts under investigation was 3.9% by RBPT and 3.1% by (I-ELISA). Multivariate logistic regression on animal level showed that locality (P < 0.05; OR: 6.254; CI, 1.186–32.976), herd size (P < 0.001; OR: 5.493; CI, 2.956-10–207), rearing with other ruminants (P < 0.001; OR: 12.433; CI, 3.957–39.060), and contact with other camels (P < 0.05; OR: 5.311; CI, 1.093–25.800) were the potential risk factors. However, herd size (P < 0.05; OR: 5.425; CI, 1.181–24.932), and rearing with other ruminants (P < 0.05; OR: 20.466; CI, 1.456–28.638) were recorded as risk factors on the herd level. The results of the present investigation indicate that the Brucella spp. exists within the camel herds in Somaliland. Further studies need to be done on Brucella infection in the other ruminants to determine which measure should be followed for control of brucellosis.     

A Study on Seasonal Variability of Trace Elemental Status of Forages for Grazing Ruminants

An investigation was conducted to determine the trace- mineral concentrations of forages in relation to requirements of ruminants grazing in natural pastures in the province of Punjab, Pakistan during two different seasons. Animals were closely followed during grazing and forages corresponding to those consumed by the animals were taken and analyzed for copper (Cu), iron (Fe), zinc (Zn), manganese (Mn), and cobalt (Co) concentrations. The data on the trace- mineral concentrations showed that most of these minerals varied greatly as a function of seasons and sampling periods. The forage Cu, Fe, and Zn concentrations were affected by seasonal changes but no influence of season was observed on the concentrations of forage Mn and Co concentration. Forage Zn and Co, during both seasons and at some sampling intervals, and forage Mn during summer were at marginal deficient levels, and in contrast, all other forage trace-minerals were within the required range for ruminants during both seasons. Based on these results, the supplementation of Zn, Co, and Mn would seem most important to support optimum livestock productivity.     

Strengths and weaknesses of the new classification system of Russian soils

Strengths and weaknesses of the new classification system of Russian soils are discussed. It is argued that the diversity of Russian soils and the ecological conditions of their formation are incompletely represented in this system. In particular, several specific groups of soils in the south of European Russia cannot be adequately classified within the framework of the new classification system. Several important tasks have to be solved before its adoption as an official document. First, it is necessary to compile correlation tables between the soil taxa of the previous classification (1977) and the new classification (2004). Second, a key for the field diagnostics of soils within the framework of the new system has to be developed. Third, the soils that are missing in the new system have to be introduced into it.     

茶皂素在刺参苗期对玻璃海鞘杀除效果的研究

为寻求刺参苗种生产期间清除玻璃海鞘的有效方法,以天然环保的茶皂素作为杀虫药物,研究了不同质量浓度的茶皂素溶液对玻璃海鞘的杀除效果及对参苗的影响.试验结果显示,茶皂素对玻璃海鞘具有致死作用,用质量浓度为5、10、20 mg/L的茶皂素溶液浸浴处理12 h,玻璃海鞘的杀除率分别为32.3％、67.7％、83.3％,用质量浓...