摩天岭北坡东南部不同海拔梯度草本植物群落特征

海拔因子是影响植被生长的主导因子,对生态系统格局与过程有着深远的影响。本研究运用相关分析、逐步回归分析和Pearson相关系数检验对摩天岭北坡南段海拔600-1 500m草本植物多样性以及群落初级生产力进行分析。结果表明,1)物种多度与海拔梯度呈显著正相关关系(R2=0.278 4)(P0.05),植物盖度与海拔梯度呈显著负相关关系(R2=0.43),草本层高度、密度与海拔梯度相关性不显著(P0.05);2)植被地上生物量随海拔梯度的上升表现出先增后减的变化趋势,地下生物量随海拔变化差异较大,表现出先增后减再增的趋势;3)从功能群的角度分析,草本层植物功能群地上生物量和地下生物量随海拔梯度的变化趋势基本一致。摩天岭北坡东南部草本植物群落特征随海拔梯度变化显著,各功能群的地上、地下生物量差异显著。生物量与草本层植被盖度呈极显著正相关(P0.01),生物量与植物高度和密度的相关性不显著,以及植物盖度、高度和密度之间相关程度不高。     

俄罗斯引进鲁梅克斯新品种在黑龙江省的推广种植

黑龙江省北部全年低温时间较长,西部地区土地盐碱化严重,是制约黑龙江农牧业发展的两大主要因素。为了筛选出与黑龙江省气候和土壤类型相适应的牧草,本研究对从俄罗斯引进的鲁梅克斯新品种‘ЩавельЧемпион’在黑龙江省不同积温带的5个具有代表性的种植点阿城、肇州、逊克、嫩江和呼玛的农艺性状和营养价值进行研究。结果表明,该品种在肇州的生长状况明显差于其它地区,而在嫩江的生长状况明显优于其它地区;产量则表现为阿城、逊克和嫩江较高,产量均在150t·hm-2以上,肇州和呼玛略低,但产量也均在120t·hm-2以上。从营养数据可以看出,阿城种植区的粗蛋白及粗脂肪含量显著高于其它地区(P0.05),其中粗蛋白为18.41%,粗脂肪为3.82%;肇州种植区的粗纤维含量显著低于其它地区,含量为10.75%,而粗灰分含量显著高于(P0.05)其它各种植区,达到14.85%;嫩江种植区钙含量显著高于其它地区;肇州种植区的干物质含量显著高于其它地区。结果表明,引进新品种‘ЩавельЧемпион’适应性强,能够在黑龙江省不同区域不同土壤上种植并推广。     

冀中平原奶牛舍温热环境评价及温热参数与生理指标的相关性分析

试验旨在评价冀中平原地区四季奶牛舍的温热环境,并分析温热参数与奶牛生理指标的相关性。选择3栋不同建筑结构的奶牛舍,对各舍温湿度和奶牛的呼吸频率、直肠温度和体表温度等生理指标进行检测。结果显示,奶牛舍四季环境温湿度和温湿指数（THI）变化显著（P<0.05）,其中夏季日均温最高,为28.59 ℃;冬季日均温最低,为1.55 ℃。奶牛夏季每天平均15.5 h遭受轻度热应激,6.0 h遭受中度热应激;冬季每天平均12.0 h遭受轻度冷应激。除冬季外,各季节不同牛舍的温度和THI均未表现出显著差异（P>0.05）。相比带矮墙或卷帘的棚舍,仅设顶子的棚舍夏季平均温度要高0.80~1.27 ℃,冬季低1.36~1.84 ℃。另外,夏季奶牛各项生理指标极显著高于其他季节（P<0.01）,且夏季不同舍奶牛的呼吸频率和直肠温度均表现出显著差异（P<0.05）,体表温度各季节差异均达显著水平（P<0.05）。从环境温湿参数与奶牛生理参数的相关性分析可看出,各项生理参数（呼吸频率、直肠温度和体表温度）与THI、环境温度均呈显著正相关（P<0.05）,但与湿度未表现出显著相关性（P>0.05）。本研究可为奶牛舍环境的评价提供科学依据,并通过环境温热参数的检测推断奶牛生理状况,为应激的发生及预警提供数据。     

Pharmacokinetics of xylazine after 2-, 4-, and 6-hr durations of continuous rate infusions in horses

Intravenous (i.v.) bolus administration of xylazine (XYL) (0.5 mg/kg) immediately followed by a continuous rate infusion (CRI) of 1 mg kg⁻¹ hr⁻¹ for 2, 4, and 6 hr produced immediate sedation, which lasted throughout the duration of the CRI. Heart rate decreased and blood pressure increased significantly (p > .05) in all horses during the first 15 min of infusion, both returned to and then remained at baseline during the duration of the infusion. Compartmental models were used to investigate the pharmacokinetics of XYL administration. Plasma concentration–time curves following bolus and CRI were best described by a one-compartment model. No differences were found between pharmacokinetic estimates of the CRIs for the fractional elimination rate constant (K_e), half-life (t_1/2e), volume of distribution (V_d), and clearance (Cl). Median and range were 0.42 (0.15–0.97)/hr, 1.68 (0.87–4.52) hr, 5.85 (2.10–19.34) L/kg, and 28.7 (19.6–39.5) ml min⁻¹ kg⁻¹, respectively. Significant differences were seen for area under the curve ( ) (p < .0002) and maximum concentration (C_max) (p < .04). This indicates that with increasing duration of infusion, XYL may not accumulate in a clinically relevant way and hence no adjustments are required in a longer XYL CRI to maintain a constant level of sedation and a rapid recovery.     

引进动物检疫备案管理的实践与思考

输入性动物疫情已成为当前甚至今后一段时期困绕国内动物疫病防控的一大难点热点问题,为应对输入性动物疫情的发生,重庆市武隆县实施了引进畜禽审批这一检疫管理措施,并在全市推广应用,取得了良好效果,。     

非法加工未检疫猪皮案的查处分析

本文介绍了山东省莱州市动物卫生监督所查处的首例违法加工、经营无动物产品检疫合格证明猪皮案,通过分析案件的查处过程与法律依据,以期为加强生产、加工、运输等环节的监管,严查动物卫生违法案件,确保动物产品质量安全提供借鉴。     

氮、磷养分添加对高寒草甸土壤酶活性的影响

本试验以典型的青藏高原高寒矮嵩草草甸(Kobresia humilis meadow)为研究平台,以表征土壤碳、氮、磷、硫养分循环的6种土壤酶为研究对象,研究土壤酶以及土壤速效养分在4年氮、磷养分添加的累积效应下的变化规律,分析和评价氮、磷养分添加对土壤养分循环方面的影响。试验结果为:氮、磷养分添加改变了土壤中速效养分的含量;氮添加与010 cm土层中的碱性磷酸酶活性有正效应,磷添加抑制了010 cm土层中的碱性磷酸酶活性;氮、磷养分添加均抑制了010 cm土层中的脲酶活性;氮添加抑制了2个土层中的纤维素酶活性;芳基硫酸酯酶活性和蔗糖酶活性没有表现出显著差异性;1020 cm土层中的几丁质酶活性在氮、磷养分添加处理下均增强,其中磷添加对几丁质酶活性的增幅最显著。结果表明:外源添加的氮在调控磷的矿化方面有促进作用,磷的添加对氮素的释放也有一定的作用;青藏高原高寒草甸受磷限制的程度可能更大。     

芡欧鼠尾草的组织培养和快速繁殖

以芡欧鼠尾草(Salvia hispanica)成熟种子为外植体,1/2MS为基本培养基,研究不同浓度的外源激素对愈伤组织的诱导、增殖和生根的影响,从而初步建立了芡欧鼠尾草组织培养的快速繁殖体系。结果表明,诱导种子愈伤组织的最适宜培养基为1/2MS+10.0mg·L~(-1) 6-BA+1.0mg·L~(-1) NAA+0.4mg·L~(-1) ZT,诱导率为66.5%;不定芽增殖的最适培养基为1/2MS+3.0mg·L~(-1) 6-BA+0.5mg·L~(-1) NAA,增殖倍数为7.69;生根的最适培养基为1/2MS+0.5mg·L~(-1) NAA,生根率达100%,平均生根数为5.68;移栽后植株生长良好,成活率较高,达97%。     

Betaine affects muscle lipid metabolism via regulating the fatty acid uptake and oxidation in finishing pig

Background: Betaine affects fat metabolism in animals, but the specific mechanism is still not clear. The purpose of this study was to investigate possible mechanisms of betaine in altering lipid metabolism in muscle tissue in finishing pigs.Methods: A total of 120 crossbred gilts(Landrace × Yorkshire × Duroc) with an average initial body weight of 70.1 kg were randomly allotted to three dietary treatments. The treatments included a corn–soybean meal basal diet supplemented with 0, 1250 or 2500 mg/kg betaine. The feeding experiment lasted 42 d.Results: Betaine addition to the diet significantly increased the concentration of free fatty acids(FFA) in muscle(P 0.05). Furthermore, the levels of serum cholesterol and high-density lipoprotein cholesterol were decreased(P 0.05) and total cholesterol content was increased in muscle(P 0.05) of betaine fed pigs. Experiments on genes involved in fatty acid transport showed that betaine increased expression of lipoprotein lipase(LPL), fatty acid translocase/cluster of differentiation(FAT/CD36), fatty acid binding protein(FABP3) and fatty acid transport protein(FATP1)(P 0.05). The abundance of fatty acid transport protein and fatty acid binding protein were also increased by betaine(P 0.05). As for the key factors involved in fatty acid oxidation, although betaine supplementation didn't affect the level of carnitine and malonyl-CoA, betaine increased mR NA and protein abundance of carnitine palmitransferase-1(CPT1)and phosphorylated-AMPK(P 0.05).Conclusions: The results suggested that betaine may promoted muscle fatty acid uptake via up-regulating the genes related to fatty acid transporter including FAT/CD36, FATP1 and FABP3. On the other hand, betaine activated AMPK and up-regulated genes related to fatty acid oxidation including PPARα and CPT1. The underlying mechanism regulating fatty acid metabolism in pigs supplemented with betaine is associated with the up-regulation of genes involved in fatty acid transport and fatty acid oxidation.     

广西边境地区活禽批发市场禽流感流行病学监测

为了给广西边境地区重大动物疫病防控阻截带建设提供数据支持,以及了解中越边境地区家禽禽流感病毒生态学,2012年12月—2017年12月,对广西边境地区主要活禽批发市场家禽及市场环境进行了系统监测。结果显示:广西边境地区活禽批发市场内禽流感病毒污染较重,呈多亚型病毒共存状态;家禽样品的平均病毒分离率为15.95%,环境样品则高达23.65%,明显高于家禽样品。市场调查发现:广西9个边境县(市、区)中,年活禽交易量在100万只以上的有5个;市场交易活禽主要为本地散养或规模场养殖家禽、从其他地区批发转运来的家禽以及边境走私家禽;大部分活禽市场没有配备消毒和无害化处理设施,也未严格执行休市制度。监测和调查结果表明,广西边境地区活禽批发市场家禽交易量大且频繁,来源复杂;市场中禽流感病毒污染严重,多亚型病毒在市场内常年蓄积循环,且存在家禽隐性带毒现象,因而有病毒散播风险。污染严重主要是因市场管理水平不高和生物安全措施不到位造成的,因此需要加强市场的动物卫生监管,提高禽流感监测力度。