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91.
Yang Zi Chi Ma Huimin Li Suting Shen Yingchun Liu Ming Li Feng Gao 《Animal Science Journal》2021,92(1):e13613
This study investigated the effects of intrauterine growth restriction during late pregnancy on the ovine fetal renal function and renal antioxidant capacity. Eighteen ewes pregnant were randomly divided into control group (CG, ad libitum, 0.67 MJ ME·BW−0.75·day−1, n = 6), restricted group 1 (RG1, 0.18 MJ ME·BW−0.75·day−1, n = 6), and restricted group 2 (RG2, 0.33 MJ ME·BW−0.75·day−1, n = 6). At 140 days, the fetal blood, allantoic fluid and kidney tissue were collected to determinate fetal renal function and renal antioxidant capacity. The results showed that the fetal weight, kidney weight, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), aquaporin-2 (AQP-2) and aquaporin-3 (AQP-3), and total antioxidant capacity (T-AOC) in RG1 group were decreased compared with the CG (P < 0.05), but the contents of β2-Microglobulin (β 2-MG), cystatin C (Cys-C), filtered sodium excretion fraction (FENa), malondialdehyde (MDA), and hydroxyl radical (OH) in RG1 group were increased (P < 0.05). The impaired ovine fetal renal growth, antioxidant imbalance and dysfunction of glomerulus ultrafiltration, and the renal tubules reabsorption were induced by maternal malnutrition during late pregnancy. 相似文献
92.
GIS是一种对地理环境等方面数据进行储存、分析、加工和呈现的综合工具。利用GIS可以把流感病例的相关数据与气候、环境和社会等数据进行整合和分析,通过统计学或数学模型,找到影响流感发生和传播的风险因素,对流感的发生趋势进行预测和可视化预警。国内外学者利用GIS在禽流感风险因素分析和预测等方面做了大量研究,包括对人感染H7N9流感、高致病性H5亚型禽流感、野禽流感风险因素和预测的研究,不同基因型病毒分布特征的研究,兽医决策辅助应用研究等。这些研究对指导兽医流行病学研究人员将GIS更好地应用于禽流感防控具有帮助意义。 相似文献
93.
在分析昌吉市土地利用现状特点和动态变化的基础上,讨论土地利用对生态环境的影响,指出昌吉市相对脆弱的生态环境和突出的人地矛盾,并提出改善其对环境影响的对策建议。 相似文献
94.
休闲农业是将农业、农产品加工和服务业相结合的新型农业产业形态。随着国民经济的发展,国民休闲需求快速膨胀,休闲农业进入了高速发展时期。可持续性发展是现阶段休闲农业亟待解决的重要问题,提高满意度是国内外学者公认的促进休闲农业发展的有效途径。在已有的休闲农业园游客满意度测评模型基础上融入东北地区休闲农业发展特点,将模型中农园参与性活动、环境、服务、消费、农园声誉和出游便利性6个满意度影响因素调整为可达程度、可参与性活动、农园形象、游客预期和价格感知5个潜变量,构建符合东北地区特点的休闲农业园游客满意度测评模型,为休闲农业游客满意度的提升进行科学指导。 相似文献
95.
Xiaosha Li Huifang Han Tangyuan Ning Ying Shen Rattal Lal 《Soil Use and Management》2019,35(4):585-594
To assess changes in organic carbon pools, an incubation experiment was conducted under different temperatures and field moisture capacity (FMC) on a brown loam soil from three tillage practices used for 12 years: no‐till (NT), subsoiling (ST) and conventional tillage (CT). Total microbial respiration was measured for incubated soil with and without the input of straw. Results indicated that soil organic carbon (SOC) and microbial biomass carbon (MBC) under ST, NT and CT was higher in soil with straw input than that without, while the microbial quotient (MQ or MBC: SOC) and metabolic quotient (qCO2) content under CT followed the opposite trend. Lower temperature, lower moisture and with straw input contributed to the increases in SOC concentration, especially under NT and ST systems. The SOC concentrations under ST, with temperatures of 30 and 35°C after incubation at 55% FMC, were greater than those under CT by 28.4% and 30.6%, respectively. The increase in MBC was highest at 35°C for 55%, 65% and 75% FMC; in soil under ST, MBC was greater than that under CT by 199.3%, 50.7% and 23.8%, respectively. At 30°C, the lower qCO2 was obtained in soil incubated under NT and ST. The highest MQ among three tillage practices was measured under ST at 55% FMC, NT at 65% FMC and CT at 75% FMC with straw input. These data indicate the benefits of enhancing the MQ; the low FMC was beneficial to ST treatment. Under higher temperature and drought stress conditions, the adaptive capacity of ST and NT is better than that of CT. 相似文献
96.
采用问卷调查、数理统计、文献资料等方法对我国滑翔伞运动损伤的情况及原因进分析。结果表明,由于滑翔伞运动本身的特点及此项运动在我国开展逐年广泛,损伤率较高,达到75%。其影响因素主要有参与者技术不够娴熟、场地因素和天气因素三方面。并根据调查结果提出预防措施。 相似文献
98.
为分析我国生猪养殖、流通和屠宰等环节的生物安全水平,提升非洲猪瘟防控工作的针对性、科学性,采用问卷调查和现场调查相结合的方式,对湖南、河南、重庆、辽宁、安徽等5个省(直辖市)15个县(市、区)的196个生猪养殖场(户)、69个生猪经纪人和19个屠宰场进行调查。结果显示:截至2019年9月,调查县(市、区)养猪场(户)数较2017年减少了50%~80%;生猪饲养模式以自繁自养为主,小规模场生物安全措施实施率较低;生猪经纪人行为复杂,如经纪对象多样、活动范围广、兼营其他相关业务、同批次收购不同养殖场(户)生猪等,仍有47.8%的经纪人称还会进圈挑选猪;73.7%的屠宰场运猪车辆没有有效执行离场清洗消毒措施。结果表明,我国生猪价值链各环节的生物安全水平仍有较大上升空间。提议继续推进规范化养殖场建设,加强生猪经纪人管理,加强生猪运输车辆的清洗消毒,促进生猪产业一体化发展。 相似文献
99.
为尽快实现上海崇明奶牛布鲁氏菌病和牛结核病(以下简称"两病")区域净化示范区净化目标,通过建立奶牛场"两病"输入性风险评估和内部风险评估模型,结合奶牛场"两病"流行史,构建了上海市规模化奶牛场"两病"风险评估分级体系;应用该体系将奶牛场划分为高、中、低风险场,为实施分类管理策略奠定基础。运用该体系,对上海市崇明区奶牛场每年开展1次"两病"风险评估分级。经过连续3年的风险分级与管理,崇明区奶牛场的"两病"净化效率得到极大提高,并使崇明奶牛"两病"区域净化示范区顺利通过国家验收,表明该体系符合上海市奶牛"两病"净化工作实际。 相似文献
100.
[Objective] Dimorphic InDel markers can be used for cotton variety identification and purity detection, to improve the accuracy and efficiency of cotton seed testing, and to play a role in molecular breeding of cotton. [Method] Based on the whole genome sequencing of 121 cotton varieties from different sources, the InDel markers with high polymorphism were developed according to polymorphism information content(PIC) and were applied in the genetic distance analysis and cluster analysis by using 66 cotton varieties in China. [Result] Totally 10 967 InDel were identified based on the next generation sequencing data of 121 cotton varieties. Among the 85 pairs of InDel primers synthesized, 64 were selected including 35 from At group and 29 from Dt group. The minimum average allelic frequency(MAF) of At and Dt chromosomes were 0.45 and 0.32, respectively, while the PIC were 0.49 and 0.40, respectively. The genetic distances of the 66 cotton varieties ranged from 0.04 to 0.65 centimorgan (cM), with an average of 0.39 cM. The two varieties with the largest genetic distance were Simian 3 and CCRI 36, and the two varieties with the smallest genetic distance were Xumian 18 and Xuza 3. [Conclusion] The 64 cotton dimorphic InDel markers can effectively reveal the relationships among varieties based on the genetic distance, and distinguish cotton varieties from different sources, which has certain theoretical significance and application value. 相似文献