基于当量因子法的甘肃省草原生态系统服务价值评估

天然草原是甘肃省最大陆地生态系统,是全省乃至全国的重要生态屏障,科学、准确地估算甘肃省天然草原生态系统服务价值,对甘肃草原重要性认识和生态安全维持具有重要意义.本研究利用甘肃省主要粮食作物产量和价格数据,计算出甘肃省生态系统服务价值基准单价,然后结合甘肃省各种草原类生物量,修正甘肃省草原生态系统服务价值当量,最后计算出甘肃省各类草原生态系统服务价值.结果表明:1)草原提供的其他单项生态系统服务价值均在食物生产和原材料生产价值的3.1倍和3.7倍以上;2)甘肃省暖性灌草丛单位面积生态服务价值最高,为84418.28元·hm?2,温性荒漠单位面积生态服务价值最低,为10120.21元·hm?2;3)甘肃省草原生态服务总价值为7069.73×108元,是2016年畜牧业总产值的23倍,约等于甘肃省2016年国民生产总值(gross domestic product,GDP);4)高寒草甸生态系统服务总价值最高,为1733.27×108元,占草原生态系统服务价值的24.52％;高寒荒漠生态系统服务总价值最低,为58.51×108元,占草原生态服务价值的0.83％.本研究不仅为区域内生态系统服务价值的估算提供了思路,也为利用法律手段保护草原提供了科学依据.     

番鸭源鸭疫里默氏菌大环内脂类药物的耐药基因检测与分析

为了解莆田市番鸭源鸭疫里默氏菌对大环内酯类药物的耐药性和相关耐药基因携带情况,对本实验室分离鉴定的49株番鸭源鸭疫里默氏菌菌株采用K-B纸片扩散法进行药敏试验,提取菌株基因组DNA,采用PCR方法对大环内酯类药物的ermA、ermB、ermC、ermF、ereD等5种耐药基因进行检测,阳性产物送公司测序并对序列进行分析...     

正安县山羊主要疫病血清抗体检测报告

为了解正安县山羊主要疫病的发展趋势,通过虎红平板凝集试验、正向间接血凝试验、酶联免疫吸附试验等方法对正安县引进山羊进行布鲁氏杆菌病、O型口蹄疫、AsiaI型口蹄疫、山羊传染性胸膜肺炎、山羊痘等主要疫病血清抗体的检测。结果表明,O型口蹄疫、AsiaI型口蹄疫和山羊痘免疫抗体阳性率分别为79．42％、81．18％和99．58％,未免疫的布鲁氏杆菌病、羊传染性胸膜肺炎的丝状支原体山羊亚种和绵羊肺炎支原体未免疫抗体阳性率分别为0％、0％和3．81％。监测结果为山羊健康的引进、培育和扩繁提供了一些基础数据,对指导养羊生产有一定的意义。     

犬前进、后退科目的训练经验

前进科目犬“前进”训练,是培养犬根据训犬员的指挥方向迅速向前奔跑的能力。口令“:前进”。手势:右手臂直伸向前与肩同高,掌心向内指向前进方向。步骤、方法:该科目应在犬坐延缓、送物衔取两科目形成且巩固的基础上进行。一、结合散放和有利的地形进行训练首先选择较直且较窄     

Effects of beta-glucan extracted from Saccharomyces cerevisiae on growth performance, and immunological and somatotropic responses of pigs challenged with Escherichia coli lipopolysaccharide

Three experiments were conducted to investigate the effects of beta-glucan supplementation on pig performance and immune function. In Exp. 1, 100 weaned pigs (8.65 +/- 0.42 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment to determine the effects of graded levels of beta-glucan. Pigs were randomly allotted to 1 of 5 treatments containing beta-glucan supplemented at 0, 25, 50, 100, or 200 ppm. Each treatment was replicated using 5 pens containing 4 pigs per pen. The ADG of pigs between d 14 to 28 and d 0 to 28 responded to dietary beta-glucan in a quadratic fashion (P < 0.05), whereas beta-glucan had no effect on ADFI and G:F in any period. In Exp. 2, 80 crossbred pigs (8.23 +/- 0.56 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment. Pigs were allotted to 1 of 2 dietary treatments (0 or 50 ppm of beta-glucan in the diet) using 10 pens with 4 pigs per pen. Pigs treated with beta-glucan had greater ADG in the 14- to 28-d (P = 0.05) and 0-to 28-d (P = 0.035) periods. The ADFI of pigs receiving beta-glucan was increased (P < 0.05) in the periods from 0 to 14, 0 to 28, and 28 to 35 d. The lymphocyte proliferation index in response to phytohemagglutinin (P = 0.051) and concanavalin A (P = 0.052) tended to decrease on d 14 in pigs supplemented with beta-glucan compared with pigs without supplementation. In Exp. 3, 24 barrows (8.89 +/- 0.20 kg of BW and 28 d of age) were used to investigate the immunological and somatotropic responses of pigs challenged with lipopolysaccharide (LPS). Experimental treatments were arranged in a 2 x 2 factorial, with the main effects of LPS challenge (saline vs. LPS) and dietary addition of beta-glucan (0 vs. 50 ppm). Pigs were raised individually in metabolic cages. Pigs were fed 0 or 50 ppm of beta-glucan for 28 d and then challenged with LPS (25 microg/kg of BW) or saline. After LPS injection, blood was obtained at 0, 1.5, 3, 4.5, 6, and 7.5 h to determine cytokine production and the somatotropic response. Dietary beta-glucan increased plasma interleukin-6 at 1.5, 3, and 4.5 h and tumor necrosis factor-alpha at 3 and 4.5 h and increased plasma interleukin-10 from 3 to 7.5 h after LPS challenge. The beta-glucan treatments had no effect on growth hormone. In conclusion, beta-glucan can selectively influence performance and partially offer benefits on somatotropic axis and immune function in weaned piglets challenged with LPS.     

Dietary Supplementation with Microencapsulated Lutein Improves Yolk Color and Lutein Content in Fresh and Cooked Eggs of Laying Hens

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 15^th 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.     

中国美利奴羊TLR2基因多态性及其与布鲁氏菌病的相关性分析

试验旨在研究Toll样受体2（Toll-like receptor,TLR2）基因的多态性及其与中国美利奴羊布鲁氏菌病易感性的相关性。利用生物信息学方法对NCBI上公布的绵羊TLR2基因序列进行比对,选出多态位点丰富的片段进行扩增,运用PCR-SSCP的方法对206个中国美利奴布鲁氏菌病阴性样本和80个中国美利奴羊布鲁氏菌病阳性样本进行TLR2基因的多态性检测,然后对不同等位基因的PCR产物进行测序,确定该基因的多态性位点,经卡方检验分析每个SNP位点的等位基因频率、基因型频率及其多态性与布鲁氏菌病易感性的相关性,利用生物信息学软件分析RNA二级结构及蛋白质的二级结构。结果表明,在279 bp的序列中共检测到3个SNPs,分别为：C1731T、G1737C和G1749T,均未引起对应氨基酸的改变,属于无义突变。这些位点在病例组和对照组之间的等位基因频率及基因型频率均不存在显著差异（P>0.05）。各突变位点均能引起RNA二级结构和最小自由能的改变,而蛋白质的二级结构均未改变。由此得出,中国美利奴羊TLR2基因的3个SNPs位点（C1731T、G1737C和G1749T）与中国美利奴羊布鲁氏菌病易感性无相关性。     

苜蓿萌发期耐盐性综合评价与耐盐种质筛选

为探明苜蓿（Medicago L.）萌发期耐盐性评价方法并筛选耐盐种质,采用加权隶属函数法对120个苜蓿种质进行综合评价并划分为不同的耐盐级别。试验以150 mmol·L^-1 NaCl溶液进行盐胁迫,以发芽势等13个性状来鉴定苜蓿对盐胁迫的反应,以耐盐系数为评价依据。结果表明：150 mmol·L^-1的盐溶液对苜蓿种子萌发和幼苗生长均有一定的抑制作用,发芽势、发芽率、萌发指数比幼苗生长受抑制的程度更大;盐胁迫对根的抑制程度大于苗。相关分析表明,加权隶属函数法可以综合评价苜蓿萌发期耐盐性。根据加权隶属函数值和聚类分析,可将120个种质分为耐盐性不同的5个级别：11个种质高耐盐（1级）、24个种质耐盐（2级）、38个种质中等（3级）、36个种质敏盐（4级）、11个种质高敏盐（5级）。     

三江源区不同建植年限人工草地根系动态特征

根系动态特征能够反映人工草地植物利用土壤资源的效率和群落恢复演替的程度.本研究以三江源区不同建植年限(5、6、9和13年)人工草地植物根系为研究对象,利用"微根管"技术,连续两个生长季(2015年5-9月和2016年5-9月)探究了4个建植年限人工草地根系动态特征.结果表明:地上生物量和丰富度在建植5～9年呈下降趋势,...     

广西西门塔尔肉牛超数排卵效果观察

[目的]为了分析广西牛超数排卵技术实施现状,[方法]试验设计在广西宾阳、都安、大化、崇左等4个肉牛养殖场(4组)各选择16头西门塔尔成年母牛作为试验母牛,采用孕酮栓(GIOB)+促卵泡素(FSH)+氯前列烯醇(PGF2)的方法对试验母牛进行超数排卵,观测试验母牛获得总胚胎数、可用胚数、一级胚数,分析超数排卵效果.[结果...