The induction of cashmere shedding via cyclophosphamide injection

The aim of this study was to investigate the effects of cyclophosphamide (CPA) on cashmere shedding in cashmere goats. Thirty‐two castrated Liaoning cashmere goats were randomly allotted to four groups, with eight replicates in each group. The four groups were injected intravenously with CPA doses of 0, 15, 20 and 25   mg/kg body weight, respectively. Feed intake, body weight, body temperature, and sphygmus were recorded and the erythrocyte count, leukocyte count, hemoglobin content, and cashmere yield and length were determined. CPA has no significant effect on feed intake, body weight, body temperature, or sphygmus of cashmere goats. It was found that CPA significantly decreased the erythrocyte count and hemoglobin content in cashmere goats on the days immediately following injection, but the effects on erythrocytes diminished within 6 days, with hemoglobin content returning to normal within 10 days. Cashmere fiber began to shed on about day 10 after injection with CPA. CPA had no significant effect on cashmere length but significantly increased cashmere yield. The results indicate that CPA can induce cashmere shedding and achieve the purpose of concentrated defleecing. A dose of 20 mg/kg body weight is preferable for hair removal and regrowth in cashmere goats.     

Does virginiamycin supplementation affect the metabolism and performance of Nellore bulls grazing under low and high gain rates?

This study aimed to evaluate the effect of virginiamycin on the metabolism and performance of growing Nellore bulls under low and high gain rates on pasture. In experiment 1, 80 Nellore bulls (age = 12 ± 2 months, body weight = 258 ± 15 kg) were assigned to 16 paddocks in a 2 × 2 randomized block factorial arrangement. In experiment 2, 12 cannulated Nellore bulls were assigned to three 4 × 4 balanced Latin squares. The factors were: (1) mineral salt without or with virginiamycin, and (2) low or high gain rate. No interaction was noted between factors (p > .10). Animals fed virginiamycin had greater average daily gain (14%, p < .01), body weight (11 kg, p = .05), plasma nonesterified fatty acid (20%, p < .01), serum calcium concentration (2.62%, p = .04), and total protozoa (p = .03) and had the same bacterial proportion (p > .27). Animals with a low gain rate had greater serum urea concentration (19.6%, p < .01) and ruminal ammonia nitrogen (62%, p < .01). Thus, virginiamycin increases the performance and changes the metabolism of growing Nellore bulls under low and high gain rates on pasture.     

Genetic parameters and trends for production traits and their relationship with litter traits in Landrace and Yorkshire pigs

Genetic parameters and trends in the average daily gain (ADG), backfat thickness (BF), loin muscle area (LMA), lean percentage (LP), and age at 90 kg (D90) were estimated for populations of Landrace and Yorkshire pigs. Additionally, the correlations between these production traits and litter traits were estimated. Litter traits included total born (TB) and number born alive (NBA). The data used for this study were obtained from eight farms during 1999 to 2016. Analyses were carried out with a multivariate animal model to estimate genetic parameters for production traits while bivariate analyses were performed to estimate the correlations between production and litter traits. The heritability estimates were 0.52 and 0.43 for ADG; 0.54 and 0.45 for BF; 0.25 and 0.26 for LMA; 0.54 and 0.48 for LP; and 0.56 and 0.46 for D90 in the Landrace and Yorkshire breeds, respectively. The ADG and D90 showed low genetic correlation with BF and LP. The LMA had ?0.40, ?0.32, 0.49, and 0.39 genetic correlations with ADG, BF, LP, and D90, respectively. Genetic correlations between production and litter traits were generally low, except for the correlations between LMA and TB (?0.23) in Landrace and ADG and TB (?0.16), ADG and NBA (?0.18), D90 and TB (0.19), and D90 and NBA (0.20) in Yorkshire. Genetic trends in production traits were all favorable except for LMA.     

发酵中药渣对断奶仔猪生长性能、血液生化指标、抗氧化能力及免疫功能的影响

为研究发酵中药渣作为饲料添加剂替代饲用抗生素的可行性,选取21日龄三元杂交断奶仔猪120头,随机分为对照组、中药渣组、发酵中药渣组和抗生素（硫酸黏菌素）组,每组设6个重复,每个重复5头仔猪,试验期28 d。试验第28天晨饲前,从每个重复中随机选取1头体重接近组内平均值的试验猪进行前腔静脉采血,分离血清,测定其生化指标、抗氧化指标及免疫相关指标。结果表明：发酵中药渣组仔猪的料重比（F/G）显著低于对照组和抗生素组（P<0.05）;发酵中药渣组血液总蛋白和白蛋白含量均显著高于抗生素组（P<0.05）,发酵中药渣组的甘油三酯和总胆固醇含量均显著低于对照组（P<0.05）;发酵中药渣组的谷胱甘肽含量及过氧化氢酶和超氧化物歧化酶活性均显著高于对照组（P<0.05）;中药渣组和发酵中药渣组血液免疫球蛋白G（IgG）、IgA、IgM含量均显著高于对照组和抗生素组（P<0.05）。综合上述结果,发酵中药渣在调节断奶仔猪血脂浓度方面可发挥一定的作用,同时可提高断奶仔猪的生长性能、抗氧化能力和免疫力,效果优于抗生素,可作为饲料添加剂代替抗生素。     

苎麻青贮及不同粗蛋白质水平精料补充料对西门塔尔牛生长性能和血清生化指标的影响

本试验旨在研究苎麻青贮饲料品质及以苎麻青贮饲料为唯一粗饲料使用时,不同粗蛋白质（CP）水平精料补充料对西门塔尔牛生长性能和血清生化指标的影响。试验将苎麻与玉米秸秆按照质量比为1：1的比例混合均匀后打捆制成苎麻青贮饲料。选择年龄相近,体重为（324.83±30.27） kg的健康西门塔尔肉牛18头,随机分为3组,每组6头,1头牛为1个重复,分别饲喂CP含量为18.0%（高CP水平,试验Ⅰ组）、16.0%（中CP水平,试验Ⅱ组）和14.0%（低CP水平,试验Ⅲ组）的精料补充料。预试期10 d,正试期60 d。结果表明,苎麻与玉米秸秆混合青贮后,感官等级评定为1级优良,pH为4.24,氨态氮（NH₃-N）含量显著增加（P<0.05）,干物质（DM）、有机物（OM）、CP、中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、钙（Ca）和总磷（TP）含量均无显著差异（P>0.05）。饲养试验结果表明,试验Ⅰ组肉牛平均日增重（ADG）最高,达到1.49 kg/d,试验Ⅱ、Ⅲ组ADG与试验Ⅰ组相比分别降低了14.09%和11.41%（P>0.05）。3个试验组的干物质采食量（DMI）和料重比（F/G）均无显著差异（P>0.05）。不同CP水平精料补充料对西门塔尔牛血清中碱性磷酸酶（ALP）、天门冬氨酸转移酶（AST）、ALT/AST、总蛋白（TP）、白蛋白（ALB）、球蛋白（GLB）、白球比（A/G）、总胆固醇（TCHO）、甘油三酯（TG）、高密度脂蛋白（HDL）和低密度脂蛋白（LDL）均无显著影响（P>0.05）,但是试验Ⅰ组血清丙氨酸转移酶（ALT）活性显著高于试验Ⅲ组（P<0.05）,但与试验Ⅱ组无显著差异（P>0.05）。综上,苎麻的营养水平较高,和玉米秸秆混合后青贮可得到品质较好的苎麻青贮饲料;将苎麻青贮饲料作为肉牛唯一粗饲料来源,高CP含量（18%）的精料补充料可提高肉牛的生长性能。     

Investigating translated data of the German soil‐quality assessment using pinpoint field validation

In contrast to modern soil‐profile characterization, alternative soil classifications, such as the German soil‐quality assessment (Bodenschätzung), bear a lower degree of scientific quality. However, despite originally created to determine the tax value of arable land and grassland, its high spatial resolution and complete areal coverage makes soil‐quality assessment a valuable tool. To assess its performance in a mountainous setting soil‐layer data of 60 soil pits, recorded in Bavaria (SE Germany) in the course of the soil‐quality assessment, were translated into German soil‐science terminology using the translation program NIBIS®. With regard to soil type and texture the translation was checked using pinpoint field validation based on soil‐science terminology. 57% of soil types and 61% of texture were correctly translated by NIBIS®. To obtain information about probable parameters that can explain the different results readily available parameters such as elapsed time between soil‐quality assessment and validation, altitude, slope, aspect, horizon thickness, lower edge of horizon, as well as weathering surface and silicate‐weathering rate derived from geological maps were used. Differences in topsoil texture were somewhat related to petrographic parameters, those of the lower subsoil showed a weak dependence to topographic parameters. The NIBIS® translation overrated the silt content to the expense of sand. Clay was the best‐matched texture class. The shift towards silty texture classes was the dominant factor for the differences of texture‐related values of the available water capacity and hydraulic conductivity. Both parameters as derived from the NIBIS® translation on the one and from field validation on the other hand were used to evaluate the water‐retention capacity of individual soil profiles. Despite differing input data the soils' water‐retention capacity was rated identical. Thus, a certain degree of disagreement between the texture data obtained from NIBIS® translation and from field validation is tolerable, if the eventual soil‐function evaluation is based on wide classes of texture or of secondary parameters derived from texture.     

美国引进甘蔗品种对黑穗病的抗性鉴定与初步评价

为筛选出抗甘蔗黑穗病的优异亲本材料,采用人工浸渍接种法对27个甘蔗品种进行1年新植试验的黑穗病抗性鉴定。通过潜育期(LP)、持续发病期(SDD)、累计丛发病率(IP)、累计茎发病率(IS)和病情进展曲线下的面积(AUDPC)这5个病情参数,结合标准对照种的抗性表现,综合评价参试品种的抗性,并采用系统聚类分析进行验证。结果表明:5个病情参数之间的相关性均达到极显著水平,是甘蔗黑穗病抗性鉴定与评价的重要指标。参试品种中,未发病品种6个,占22.22%;高抗(HR)品种5个,占18.52%;抗病(R)品种10个,占37.04%;中抗(MR)品种1个,占3.70%;中感(MS)品种2个,占7.41%;感病(S)品种3个,占11.11%。系统聚类分析的结果与参试甘蔗品种的抗性表现一致。     

脲醛树脂合成工艺参数的优化

以F/U的终摩尔比、F/U的初摩尔比、缩聚阶段pH值、缩聚阶段温度为变量,UF中游离甲醛含量和羟甲基含量为考核指标来设计正交试验,优化脲醛树脂合成工艺参数。最佳工艺参数F/U的终摩尔比1.05:1、F/U的初摩尔比2.2:1、缩聚阶段pH值5.1～5.3、缩聚阶段温度88℃～90℃。其产品游离甲醛含量小于0.15%,羟甲基含量大于10.5%。     

Effects of different mulching practices on the photosynthetic characteristics of hot pepper (Capsicum annuum L.) in a greenhouse in Northwest China

Mulching is considered a desirable management technology for improving and stabilizing agricultural crop production. The aim of the present study was to evaluate the effect of different mulching practices on hot pepper (Capsicum annuum L.) performance in terms of leaf photosynthetic capacity, photosynthetic light response (PLR) curves, and growth parameters, under greenhouse conditions. Consequently, field experiments were conducted during the 2011 and 2012 growing seasons in Northwest China using four types of mulching practices (without mulch; wheat straw mulch; plastic film mulch; and combined mulch with plastic film and wheat straw). The results showed that mulching increased the leaf net photosynthesis rate, stomatal conductance to water vapor, intercellular CO₂ concentration, water-use efficiency, and transpiration rate. Mulching significantly affected the PLR curves, and important parameters (such as the apparent quantum yield, maximum net photosynthetic rate, light compensation point, and light saturation point) were all improved under combined mulching conditions when compared with other mulching practices. Therefore, it is inferred that hot pepper leaf photosynthetic capacity and light-use efficiency were significantly improved under combined mulching, and thereby the combined mulching is recommended for hot pepper cultivation in greenhouses due to working well to facilitate soil condition (moisture and temperature), plant growth, and marketable photosynthetic characteristics.     

倍半萜类抗癌抑制剂的定量构效关系研究

对具有抑制人早幼粒白血病细胞(HL-60)活性的倍半萜类化合物进行二维定量构效关系研究,利用遗传算法建立2D-QSAR模型,得到10个具有较好预测能力的QSAR模型。分析模型得出:脂水分配系数(ALogP)、分子量(Molecular_Weight)与化合物活性呈正相关,偶极距x分量(Dipole_X)、分子表面积(Molecular_SurfaceArea)与化合物活性呈负相关;倍半萜2D-QSAR模型中独特的2个分子参数分别是VSA_AlogP[2]和VSA_AlogP[10];VSA_AlogP[2]参数与化合物抗癌活性呈正相关,在此区域内增加羟基等影响分子脂水分配系数的官能团能增加化合物的抗癌活性,VSA_AlogP[10]参数与化合物活性呈负相关,此区域内减少羟基等影响分子酯水分配系数的官能团会增加化合物的抗癌活性。该组模型将为新型抗癌类药剂的筛选以及新型抗癌类药物设计提供指导。