Effect of Humidity on Broiler Health and Corresponding Measures

With the development of intensive broiler raising, the influence of environmental factors on broiler health are increasingly prominent. Relative humidity is one of the most important indicators of broiler house environment.But in the production process of broiler farming,it is often neglected on the management of humidity in house. Neither low humidity nor high humidity is conducive to the healthy growth of broilers. It is of great significance to strengthen the monitoring of the humidity in broiler houses and study the effects of relative humidity on the health of broiler for guiding the rational control of the humidity in broiler houses and the development of healthy breeding. In this paper, we summarized and analyzed the effects of relative humidity on thermal regulating,growth performance, reproductive performance, blood parameters, meat quality and respiratory tract of broilers, and the monitor and control measures of humidity in the poultry house, aimed to provide a reference for further research on the mechanism of relative humidity affects broiler health and rational regulation of humidity in broiler house.     

Study on Environmental Quality Parameters in Broiler House with Three-overlap Cages in Winter and Autumn

The study was conducted to detect the indoor environmental quality parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. In the process of feeding, the same farming house in the same farm was chosen to carry out the test. The indoor ambient temperature, humidity and the air quality were determined in chicken house in different seasons. The measure points were distributed in 4 different positions in the house. The experiment period was from 3 to 6 weeks of broilers.The results showed that there was no significant difference in the ambient temperature between autumn and winter during experimental period (P >0.05). The ambient temperature in the house in winter was slightly higher than in autumn. The humidity in autumn was significantly higher than that in winter (P <0.05).The temperature and humidity in two seasons could meet the requirements of broiler growth. There was no significant difference in ammonia concentration between autumn and winter, while ammonia level in winter was slightly higher than that in autumn. The carbon dioxide in the house was significantly higher in winter than that in autumn (P <0.05). The total number of airborne bacteria in winter was significantly higher than that in autumn (P <0.05). The indoor temperature kept constant in autumn and winter seasons in closed poultry house. In winter, the humidity was reduced, the carbon dioxide concentration was increased, and the total number of bacteria in the air was increased.So, the ventilation should increase at the same time of heating in winter.     

Representativeness-based sampling network design for the State of Alaska

Resource and logistical constraints limit the frequency and extent of environmental observations, particularly in the Arctic, necessitating the development of a systematic sampling strategy to maximize coverage and objectively represent environmental variability at desired scales. A quantitative methodology for stratifying sampling domains, informing site selection, and determining the representativeness of measurement sites and networks is described here. Multivariate spatiotemporal clustering was applied to down-scaled general circulation model results and data for the State of Alaska at 4 km² resolution to define multiple sets of ecoregions across two decadal time periods. Maps of ecoregions for the present (2000–2009) and future (2090–2099) were produced, showing how combinations of 37 characteristics are distributed and how they may shift in the future. Representative sampling locations are identified on present and future ecoregion maps. A representativeness metric was developed, and representativeness maps for eight candidate sampling locations were produced. This metric was used to characterize the environmental similarity of each site. This analysis provides model-inspired insights into optimal sampling strategies, offers a framework for up-scaling measurements, and provides a down-scaling approach for integration of models and measurements. These techniques can be applied at different spatial and temporal scales to meet the needs of individual measurement campaigns.     

Progress on role of exosomes derived from leukemia cells

Exosomes are bilayer-lipid membrane nanovesicle from almost all living cell types which are involved in intercellular substance transporting and signaling communication. Exosomes are 30~120 nm in diameter, can transfer bioactive molecules including DNA, RNA, microRNA, protein as well as lipids derived from parents' cells to recipient cells by body fluids, and specifically influence their physiological or pathological conditions. Leukemia is due to malignant proliferation of hematopoietic stem and progenitor cells. It was reported that leukemia cells derived exosomes play a key role in disease progression, drug resistance, and predict prognosis. This paper will outline the role of exosomes derived from leukemia cells and provide important information to help explore the molecular pathogenesis, biomarker as well as therapeutic target of leukemia.     

Gonadotropin-releasing hormone-induced luteinizing hormone release in heifers: effect of nutrition during gestation

The effects of nutrition during the last two trimesters of gestation on GnRH-induced LH release were assessed in crossbred heifers. Heifers (n = 58) were allotted at 90 d gestation to one of three levels of an experimental diet fed at 1, 1.5 or 2% of BW to attain maternal BW loss, BW maintenance or BW gain, respectively, at parturition. Twenty-two heifers were injected (i.m.) once with 100 micrograms GnRH between d 14 and 1 before parturition, and 32 heifers were injected (i.m.) once with 100 micrograms GnRH between d 8 and 21 after parturition. Jugular blood samples were collected before and at 30-min intervals after GnRH for 4 h. Least squares means for BW change differed (P less than .01) among BW loss (-17.6%), BW maintenance (-6.0%) and BW gain (7.0%) heifers. Basal plasma LH concentration was not influenced by nutritional treatment and was similar before and after parturition for all groups. However, in response to GnRH, peak plasma LH concentration was greater (P less than .10) for prepartum than for postpartum heifers. Mean LH peak amplitude in prepartum heifers was approximately twofold greater (P less than .10) in the BW loss and maintenance groups compared with the BW gain group. Prepartum LH release was related inversely (r = -.64) to change in heifer BW and increased (P less than .01) as BW loss increased during gestation. After parturition, mean LH peak amplitude and area under the response curve averaged 50% less (P less than .10) in the BW loss and maintenance groups than in the BW gain group.(ABSTRACT TRUNCATED AT 250 WORDS)     

三尖杉的育苗技术

针对三尖杉种子休眠期长、发芽率极低(仅10%) 的问题,经近10年的试验研究,初步掌握了三尖杉种子的采收加工和播种育苗技术。以此 为基础,从采收及种子处理、种子层积催芽、播种育苗、育苗期的管护措施等方面,详细介 绍了三尖杉的育苗技术。     

木材缺陷图像的灰度形态滤波

介绍数学形态学中的灰度形态滤波方法,给出对木材缺陷图像进行闭、开运算处理后的仿真图像实例,利用木材缺陷图像截面灰度分布对处理效果进行分析.结果表明:采用灰度形态滤波方法对木材缺陷图像进行滤波处理,可有效去除木材缺陷图像中的噪声,改善图像的视觉效果,提高后期缺陷边缘检测的精确度,从而证明该方法对木材缺陷图像进行滤波处理是可行的.     

基于高温诱发树木多倍体的模糊PID温度控制器

针对树木枝芽的室外高温诱发多倍体处理,介绍了一种模糊PID温度控制器,该控制器具有显示温度、设定温度、自动控制温度等功能。控制器采用PID参数模糊自整定方法,充分发挥了其动态响应好、上升时间快、超调小的特点,具有较高的动态跟踪品质和稳态精度,并在实际应用中取得了较好的控制效果。