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941.
Lingying Xu Meiyan Wang Yutian Tian Xuezheng Shi Yijie Shi Quanbo Yu Shengxiang Xu Xiangwei Li Xinqiao Xie 《Soil Use and Management》2019,35(3):412-420
Organic farming can potentially mitigate soil compaction, which commonly occurs in vegetable plantations, particularly in greenhouses when compared with open‐air systems. Although several studies have addressed the effect of planting patterns on soil pore characteristics, few studies have focused on changes in pore attributes under organic fertilization. We used adjacent fields during green manure planting as a control to compare the differences in soil physicochemical and macropore parameters between 14‐year‐old greenhouse plots and open‐air plots under organic fertilization. Pearson's correlation analysis was performed to analyse the drivers of soil macropore characteristics in vegetable plantations in Jiangsu Province, China. A significant increase in connectivity, fractal dimensions and total macroporosity and a decrease in bulk density after 14 years of organic farming, particularly in the surface layer in the greenhouse, were observed. However, the difference in pores in the plough pan layer was not significant between the treatments. The volume of small pores (50–500 μm) and medium pores (500–1,000 μm) increased significantly (p < 0.05) in both the greenhouse and open‐air systems, showing significantly positive relationships with soil organic matter (SOM) and total nitrogen (TN) content. Large pores (>1,000 μm) showed a clear decrease, especially in open‐air fields, possibly due to the disappearance of the original straw residues in the surface layer. Small and medium pores in the plough layer increased in greenhouse fields, whereas the opposite occurred in open‐air fields. Overall, compared with open‐air systems, long‐term organic greenhouse patterns had a significantly positive effect on soil pore attributes. 相似文献
943.
Fengge Wang Lu Chen Shuxiong Chen Liang Deng Meng Tian Biaobiao Zheng Chunjin Li Xu Zhou 《Reproduction in domestic animals》2019,54(7):972-978
Follicular cysts, which is a common infertility disease, can cause financial losses in pig breeding programmes. The pathogenesis and mechanisms of the formation of follicular cysts are not understood clearly. In our previous study, the concentration of retinol‐binding protein 4 (RBP‐4) in the follicular fluid (FF) of the ovary with follicular cysts was found to be significantly higher than that of normal ovary, thereby suggesting that RBP‐4 may be a candidate biomarker for porcine follicular cysts. To study the association of RBP‐4 and follicular cysts further, we detected the polymorphisms of the RBP‐4 gene and the presence of follicular cysts by PCR‐Restriction fragment length polymorphism (RFLP) assay. In this study, we screened the mutations of RBP‐4 gene in 79 sows with follicular cysts and 100 normal sows without cysts. Results showed that +249‐63G>C polymorphisms were significantly associated with follicular cysts, and sows with CC genotype in RBP‐4 gene had a high risk of developing follicular cysts. Hence, our findings further proved that RBP‐4 may be a novel biomarker for follicular cysts, which may be valuable for the diagnosis of follicular cysts and molecular breeding of pigs. 相似文献
944.
Chao Wen Yue Su Zhengguo Tao Zongjia Cheng Di Zhou Tian Wang Yanmin Zhou 《The Journal of Poultry Science》2021,58(2):97
This study was conducted to compare the efficacy of diet supplemented with non-microencapsulated lutein (NL) and microencapsulated lutein (ML) in laying hens. A total of 270 Hy-line Brown laying hens (54 weeks old) were allocated to three groups with six replicates of 15 hens and were adapted to a wheat-soybean meal basal diet for two weeks. Next, the control birds were fed the basal diet, and the test birds were fed the basal diet supplemented with 600 mg/kg NL (12 mg/kg available lutein) or 90.1 mg/kg ML (10 mg/kg available lutein) for 35 days. Supplementation of lutein did not affect the productive performance of laying hens, but improved (P<0.05) the yolk color and red/green value (a*), with eggs from the ML group displaying improved color and a* values from the 15th day of the experimental period. The blue/yellow value (b*) for the yolk showed an increase (P<0.05) through both NL and ML supplements. The yolk color of fried and boiled eggs and a* value of the yolk in fried eggs were improved (P<0.05) only through ML supplemented diet. Both NL and ML supplements resulted in lower (P<0.05) lightness and higher (P<0.05) a* values of yolk in boiled eggs, as well as higher (P<0.05) b* values in fried and boiled eggs. Yolk lutein content in fresh, fried, and boiled eggs was increased (P<0.05) in NL and ML groups with the latter being higher. In conclusion, ML improved yolk pigmentation and lutein retention in laying hens better than NL. 相似文献
945.
黄霉素、肉碱对草鱼生长性能、肌肉成分和血清生理生化指标的影响 总被引:3,自引:0,他引:3
将平均体重(134.3±12.1)g的草鱼(Ctenopharyngodon idella)分成3组,饲喂在基础饲料(对照组)中分别添加8mg/kg黄霉素和200mg/kgDL-肉碱的饲粮,养殖8周后,各组鱼体增重率分别为156.29%、165.46%、167%,黄霉素、肉碱组较对照组提高了5.87%、6.85%(P<0.05);与对照组相比,饲料中添加黄霉素降低草鱼肌肉蛋白含量3.92%(P<0.05),提高血清丁酰胆碱酯酶活性43.49%(P<0.05),对草鱼血清非特异性免疫指标无显著影响(P>0.05);与对照组相比,添加肉碱组血清胆固醇含量降低11.54%(P<0.05)。 相似文献
946.
中药添加剂对高温下猪血清抗氧化功能的影响 总被引:3,自引:0,他引:3
为探讨中药添加剂对高温应激仔猪抗氧化功能的调控效果,选用35日龄中国实验用小型猪64头,分为对照组、应激组和2个中药添加剂组(方1、方2),分别于试验第1,2,4,6,10天采血清,测定超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)的含量变化。结果发现:与对照组相比,应激组猪血清SOD活力在第1天显著升高;MDA含量在第6天显著升高;GSH-Px活力在第6和10天显著高于常温组(P<0.05)。与应激组相比,方2组的GSH-Px活力在第2天显著升高,方1和方2组MDA含量在第10天显著降低(P<0.05)。表明高温状态下,猪体内MDA含量增加,GSH-Px活性增强;中药添加剂能促进热应激仔猪抗氧化功能的恢复和提高,且方2效果优于方1。 相似文献
947.
添加中草药对饲料蛋白质消化率的影响 总被引:1,自引:0,他引:1
试验采用体外消化法研究添加不同剂量的两种中草药对饲料蛋白质消化率的影响.选用陈皮、山楂两种中草药,然后在体外环境下模拟猪胃肠道消化环境进行测定.结果表明:(1)添加中草药陈皮A组(0.5%)和C组(1%)的消化残渣蛋白质质量和粗蛋白质消化率与对照组相比差异极显著(P<0.01),而B组(0.75%)与对照组相比差异显著(P<0.05).(2)添加中草药山楂D组(0.5%)、E组(0.75%)、F组(1%)三个组的消化残渣蛋白质质量和粗蛋白质消化率与对照组相比差异极显著(P<0.01).(3)山楂的效果明显好于陈皮,且山楂添加量为0.75%时最好. 相似文献
948.
研究了虾颗粒饲料的表面完整性、切口平整性、长短均一性对耐水性的影响.结果表明:硬颗粒饲料表面有裂纹、切口不平整、长短不一致都会降低饲料在水中的稳定性.虾饲料生产厂家应重视产品的表观质量,加强生产过程监管. 相似文献
949.
近年来,羊多杀性巴氏杆菌病在内蒙古自治区呼伦贝尔市时有发生。为了解呼伦贝尔市羊源多杀性巴氏杆菌荚膜血清型流行状况,通过建立多杀性巴氏杆菌分子生物学诊断方法,以羊病变组织为研究对象,对呼伦贝尔市羊源多杀性巴氏杆菌,进行荚膜血清群分子流行病学调查,同时应用K-B纸片琼脂扩散法,对分离菌株进行药物敏感性试验,以找到针对本地区流行株的敏感药物。结果显示:从采集的35份病羊肺组织病料中,分离出12株B群、9株D群多杀性巴氏杆菌,未分离出其他血清群;分离菌株对青霉素、链霉素耐药率最高,对氯霉素、四环素、诺氟沙星、环丙沙星敏感。结果表明,呼伦贝尔市流行的羊源多杀性巴氏杆菌以B群、D群为主,且分离菌株对青霉素、链霉素产生了较高的耐药性,需指导和监管抗菌药物的合理使用。本研究查清了本地区流行的优势多杀性巴氏杆菌血清群,找到了针对性敏感药物,这为该市羊巴氏杆菌病防控提供了有效的技术支撑,也对多杀性巴氏杆菌病流行病学监测和基因多样性研究奠定了基础。 相似文献
950.
为了探究小尾寒羊脂肪细胞分化过程中相关基因的变化规律,试验采集2月龄小尾寒羊腹股沟白色脂肪组织,通过酶消化法体外分离小尾寒羊前体脂肪细胞。培养前体脂肪细胞布满细胞板后,分别用诱导Ⅰ液、诱导Ⅱ液对细胞进行诱导分化,使其成为成熟的脂肪细胞。利用油红O染色法验证成熟脂肪细胞并检测脂滴含量。分别在增殖期细胞增殖70%、90%及分化期诱导Ⅰ液处理48 h、诱导Ⅱ液处理48 h、完全培养液处理48 h时(2、4、6、8、10 d)提取细胞总RNA,反转录成cDNA。采用实时荧光定量PCR检测PPARγ、C/EBPα、LPL、SREBP1、KLF5、KLF6、FABP4、STAT5、ACSS2、IGF1、ADD1、FOXO1、ACACA、DGAT1、CPT1A基因的表达规律。结果表明,试验成功分离并诱导前体脂肪细胞变为成熟的脂肪细胞,细胞内部具有明显脂滴;实时荧光定量PCR结果表明,上述基因在细胞分化阶段具有明显波动,峰值出现的时间均不相同;C/EBPα、FOXO1基因表达峰值出现在第6天,可能在细胞分化早期发挥作用;PPARγ、LPL、SREBP1、KLF5、KLF6、FABP4、STAT5、ADD1、ACSS2基因表达峰值出现在第8天,但表达倍数与趋势均不相同;ACACA基因表达量出现上下波动;IGF1、DGAT1基因表达峰值出现在第10天;CPT1A基因表达量则一直下降;FABP4基因表达倍数显著高于其他基因。本研究全面检测了小尾寒羊前体脂肪细胞在分化过程中关键基因的表达规律,可为探究小尾寒羊脂肪分化过程分子机制、挖掘参与脂肪分化新的关键基因、提高小尾寒羊肌间脂肪含量等研究提供一定的理论参考。 相似文献