大力发展草产业 稳步推进海北高原现代生态畜牧业建设

草产业是发展生态畜牧业的灵魂和核心,草畜平衡是畜牧业结构调整和生态保护可持续发展的关键。多年来,海北州认真贯彻落实科学发展观,在发展草产业方面进行了大胆而有益的探索和尝试。     

论养蜂业在农业中的地位和作用

本文从农业增产、环境可持续发展、环境监控和治理、守护人类健康、建设"节约型社会"、农民增收、蜂产品出口创汇等方面综述了蜂业在我国农业中的地位和作用,阐述了我国养蜂业在世界的地位,并对今后的发展潜力和趋势进行了预测。     

黄土高原子午岭林区生态气候效应特征

为揭示黄土高原中心地带子午岭林区生态气候效应特征,利用子午岭林区太白镇气象站气候资料和周边非林地华池县和庆城县气象站同步观测资料,分析月气象要素的年变化曲线和资料序列方差的统计检验结果表明：子午岭林区各月平均气温明显低于周边地区,林地5、7、9月降水量及4-9月降水时间和空气湿度明显多（大）于周边地区,林地盛夏（6-8月）月平均蒸发量明显偏小,表征黄土高原子午岭林地的生态气候效应具有明显的冷凉、湿润和水分利用率高的特征。     

Comparison of growth performances,carcass characteristics,and meat qualities of Okinawan indigenous Agu pigs and crossbred pigs sired by Agu or Duroc boar

Indigenous Okinawa Agu pigs are crossed with Large White × Landrace (WL) pigs to improve their meat production, but there is little information regarding the crossbreeding effects. The study aims to compare growth, carcass characteristics, and meat qualities of Agu pigs with those of WL crossbreeds with Agu sires (WLA) or Duroc sires (WLD). WLA pigs showed better growth performance and carcass characteristics and less intramuscular fat (IMF) contents than Agu ones, but they had higher fat deposition, smaller longissimus dorsi muscle area, and higher IMF contents than WLD pigs. Agu pigs showed higher water holding capacity than the other two breeds. The inner layer of Agu backfat contains higher and lower proportions of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acid (PUFA), respectively, than that in WLD animals. WLA animals had intermediate values for the fatty acid content in the inner backfat, although MUFA contents were equal to those of Agu pigs. Fatty acid profiles in IMF were similar to those in the backfat. These results indicate that crossbreeding of Agu with WL pigs improves growth performance and carcass quality. Particularly, WLA pigs have higher IMF contents and MUFA concentrations and lower PUFA concentrations than WLD pigs.     

施肥梯度对甘南高寒草甸植被特征的影响

通过小区控制施肥实验,研究了施肥梯度对青藏高原东缘高寒草甸植被特征的影响.结果表明,1) 施肥使线叶嵩草、波伐早熟禾、垂穗鹅观草等禾草的高度显著增加,异针茅、瑞玲草等非禾草类的高度减少.2) 随着施肥梯度的增大,群落的总密度逐渐下降, 禾草密度在不同施肥梯度下有时增加,有时减少,无一般性规律;而非禾草物种密度一般是减少的.3) 随施肥梯度的增加,地上生物量明显提高,多样性指数逐渐下降.施肥对群落密度、地上生物量和多样性的作用都要在2年以后才表现出明显的规律.     

DOES MEASUREMENT OF SMALL INTESTINAL DIAMETER INCREASE DIAGNOSTIC ACCURACY OF RADIOGRAPHY IN DOGS WITH SUSPECTED INTESTINAL OBSTRUCTION?

The ratio between maximal small intestinal (SI) diameter and the height of the body of the fifth lumbar vertebra (L5) in radiographs has been reported as a diagnostic test in dogs with suspected intestinal obstruction. In order to assess the effect of the SI/L5 ratio on the accuracy of radiographic diagnosis of intestinal obstruction, lateral abdominal radiographs of 37 dogs with small intestinal obstruction and 48 nonobstructed dogs were mixed and examined independently by six observers who were unaware of the final diagnosis and who represented a range of experience. Observers first examined radiographs subjectively and stated the likelihood of obstruction (definitely not, probably not, equivocal, probably, definitely). Observers subsequently reexamined the radiographs, determined the SI/L5 ratio, and again stated the likelihood of obstruction. The most frequent cause of obstruction was foreign body (29/37, 78%). Dogs with SI obstruction had a significantly larger median SI/L5 ratio than nonobstructed dogs (P = 0.0002). Using an SI/L5 ratio of 1.7 for diagnosis of intestinal obstruction, sensitivity and specificity were 66%. Use of the SI/L5 ratio was not associated with increased accuracy of diagnosis for any observer, regardless of experience, hence this test may have no diagnostic impact.     

祁连山南麓高寒灌丛GPP变化特征及对生长季积温的响应

全球气候变化背景下气温逐渐升高,将会对陆地生态系统碳循环产生重要影响.研究利用2003-2016年的涡度相关系统观测资料,研究了祁连山南麓高寒灌丛生长季(5月-9月)总初级生产力(gross primary productivity,GPP)在不同时间尺度上对生长季有效积温(growing season degree ...     

肥料不同配比对水稻产量与蛋白质含量的影响

为了指导水稻生产合理施肥，采用田间小区试验，研究了氮、磷、钾、硅锰、有机肥配合施用对水稻养分迁移、光合特性、籽粒产量及蛋白质含量的影响．结果表明：氮、磷、钾、硅锰、有机肥配合施用能促进水稻氮、磷、钾的吸收、转运、累积，提高籽粒氮、磷、钾含量及籽粒粗蛋白质含量；氮、磷、钾、硅锰、有机肥配合施用对水稻产量的形成有明显的促进作用，主要是通过提高功能叶的净光合速率、有效穗、每穗实粒数来实现．     

多年生香豌豆在黄土高原地区引种适宜性评价

多年生香豌豆从美国引种后在黄土高原大部分地区的适应性较强。结合气候相似法、模糊综合评判法以及引种栽培试验,得出多年生香豌豆的适生中心区位于气温适中的黄土高原中部呈西南～东北走向的一个狭长地带,主要包括黄土高原沟壑区、丘陵沟壑区二副区、三副区以及太行山西部山地类型。     

鸡传染性法氏囊病超强毒致弱株的生物学特性研究

将vvIBDV国内分离株-G株经SPF鸡胚和鸡胚成纤维细胞连续传代致弱,得到适应细胞的致弱株。暂命名为IBDVGt。其毒价为2.0×108PFU／ml以上,具有较好的抗原性,对鸡无致病性。返祖试验及病理组织学试验证明,致弱株可在鸡体内连续传至4代,未有返强现象。