结缕草属杂交后代抗寒性评价

以结缕草(Zoysia Willd.)杂交后代为材料,以Z014(马尼拉)、Z129(青岛结缕草)及Z077(“兰引3号”结缕草)为对照,以电解质外渗法和地下茎恢复性生长评价其抗寒性,分析抗寒性、枯萎期及青绿期的回归关系。结果表明:叶片电解质外渗率半致死温度(LT₅₀)的变化范围为-5.78~-8.26℃,其中22-2、40-2和40-8的半致死温度均低于对照;叶片半致死温度由低到高,即抗寒性由强到弱依次为22-2>40-2>40-8>Z077>Z129>Z014>40-5>31-3>18-1>18-4>37-1>22-3;地下茎恢复生长试验结果表明,杂交后代在-6℃时全部致死,在-2℃处理后均可以恢复生长,恢复生长的百分率变异较大(14.7%~100%),其中31-3与40-2超过Z014与Z077,22-2超过Z077;供试材料间叶片和地下茎抗寒性的测定结果一致;回归分析结果表明,叶片的半致死温度、青绿期及枯萎期相关不显著。     

绿地格局与温度的关系

研究旨在按照既定的尺度研究绿地格局与温度之间的关系。绿地格局利用绿地格局指数来做表征,从斑块规模、边界特征、空间特征3 方面来选取指数,温度利用遥感影像反演得到。结果表明：斑块数量超过400 时,平均斑块面积和斑块面积的离散度在一定区域变化时,温度才会下降。平均斑块的边界复杂度保持在一定区域变化时,温度才会下降。空间位置的结果也表明当平均邻近指数和平均邻近距离保持在一定区域变化时,温度才会下降。研究结果对建设城市绿地有一定的实践指导意义。     

规模养蚕新技术的研究Ⅰ.大棚养蚕温湿度对蚕茧产质量的影响

试验调查了大棚养蚕春、夏大蚕期与蔟中的温湿度变化,以探索有利于大棚养蚕的饲养技术与小气候调节技术.棚内温湿度变化对蚕茧产质量的影响比较分析表明,春期5龄后期和上蔟初期,35～38.8℃的高温对蚕茧产质量有较大影响;夏蚕期棚内温度明显高于春蚕期,最高超过40℃,连续高温持续时间长,昼夜温差大.根据春、夏期不同的气候特点,春期大棚上蔟初期要重点进行降温排湿,夏期重点进行降温.     

肃南县荒漠化草原大沙鼠防治效果

近几年肃南县发生不同程度的草原鼠害,给当地畜牧业带来了巨大的经济损失。特别是2012年肃南县荒漠化草原大沙鼠危害呈"爆发"趋势,鼠灾发生对实施退牧还草禁牧区的草原生态环境和水土保持造成严重破坏,加剧了草场退化和荒漠化进程。     

西部农村发展奶牛小区的优势及注意问题

西部农村饲草资源充裕,发展奶牛养殖小区有利于减少草料运输费用,有利于减轻城郊养牛环境污染,有利于改善牛奶质量。本文提出小区建设应注意的五个问题:注重奶牛质量;采用胚胎移植技术,提高小区牛群的个体产奶量:种养结合,建立与奶牛养殖业配套的饲草生产基地;改进饲养管理,推行混合日粮饲养技术;实行行业准入制度,控制小区环境污染,提高牛奶质量,生产绿色奶品。     

Effects of three methods of restraint an in rhesus and african green monkeys intravenous glucose tolerance testing

The intravenous administration of 0.75 gm glucose per kg and the measurement of serum glucose pretest and at 10, 20, 30, 60, 90 and 120 minutes constitute a satisfactory protocol for intravenous glucose tolerance testing of Rhesus (Macaca mulatto) and African Green (Cercopithecus aethiops) monkeys. No significant differences were noted between animals restrained with ketamine hydrochloride and those restrained with sodium pentobarbital, but the African Green males and females and the male Rhesus monkeys yielded significantly different results while being manually restrained.     

Green tea flavan-3-ols and oligomeric proanthocyanidins inhibit the motility of infective larvae of Teladorsagia circumcincta and Trichostrongylus colubriformis in vitro

The effects of a hot water infusion and an aqueous acetone extract of green tea (Camellia sinensis) on the motility of infective larvae of the sheep nematodes Teladorsagia circumcincta and Trichostrongylus colubriformis were investigated under in vitro conditions. The infusion and extract dose-dependently inactivated the infective larvae as assessed by the larval migration inhibition (LMI) assay. To determine the components responsible for the inhibitory activity, the hot water infusion and aqueous acetone extract of green tea were fractionated on Sephadex LH-20 and the green tea extract fractions (GTE-I-VIII) characterised by mass spectrometry. The larvae were exposed to increasing concentrations of these GTE fractions. Fractions containing epigallocatechin gallate (EGCG) and proanthocyanidin oligomers were most effective. GTE fractions were more effective against T. circumcincta than T. colubriformis larvae as assessed by the LMI assay.     

季节对山羊反刍行为的影响

对１６只中卫山羊母羊的青草期和枯草期反刍行为进行观察表明，山羊在青草期，每天（２４ｈｒｓ）有１０个反刍周期，反刍持续总时间为３０４．２分，共反刍４２５．３次，每个食丸在口腔中咀嚼４３．０秒，共咀嚼４６．４次，在枯草期上述指标分别为１１个，４２０．０分，４７２．０次，５３．４秒和５９．６次，季节对山羊反刍行为的影响，本质上决定于羊采食牧草的品质和数量，优质牧草（青草期）能够缩短反刍持续总时间（Ｐ〉０     

RABBIT HEMORRHAGIC DISEASE VIRUSES DETECTED IN PET RABBITS IN A COMMERCIAL LABORATORY IN EUROPE

Rabbit hemorrhagic disease (RHD) is an important cause of disease and mortality in wild and domestic European rabbits (Oryctolagus cuniculus) throughout the world. Testing for 2 distinct RHD virus types (RHDV/RHDVa and RHDV2) was carried out on samples collected from 684 rabbits submitted from veterinary practices and private owners throughout Europe between January 2015 and June 2017. Four (0.6%) were positive for RHDV/RHDVa and 257 (37.4%) were positive for RHDV2. RHDV/RHDVa was detected in individual samples from Germany and the Netherlands, while RHDV2 was found in animals from Germany, Great Britain, Luxembourg, The Netherlands, Spain, Switzerland, Poland, Belgium, Austria, Sweden, and Finland.     

Green tea polyphenols supplementation alters immunometabolism and oxidative stress in dairy cows with hyperketonemia

Peripartal cows often experience negative energy balance, and are therefore prone to suffering from metabolic diseases such as hyperketonemia, which causes financial losses in dairy farms. This study aimed to investigate the effect of green tea polyphenol (GTP) supplementation during the periparturient period on production performance, oxidative stress and immunometabolism in dairy cows with hyperketonemia. One hundred Holstein cows were assigned to GTP (0.2 g/kg DM; n = 50) or control (without GTP; n = 50) group based on body weight, previous milk yield, and parity on d 15 before expected parturition. Subsequently, 10 cows with hyperketonemia were selected from each group, according to blood β-hydroxybutyric acid (BHBA) concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum. All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum. Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10, 20, and 30 d postpartum. Compared with control cows, greater milk yield and lower somatic cell count were observed in GTP cows. The GTP group had lower concentrations of BHBA, free fatty acids, cholesterol, triglyceride, reactive oxygen species, malondialdehyde, and hydrogen peroxide, greater concentrations of glucose, lower activities of aspartate aminotransferase, alanine aminotransferase, and glutamyl transpeptidase, alongside greater activities of superoxide dismutase, glutathione peroxidase, and total antioxidant capacity. Additionally, GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10, but down-regulated concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-2, interleukin-8, and interferon-γ in plasma. Greater concentrations of plasma immunoglobulin G were also detected in the GTP group. Overall, the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hyperketonemia during early lactation.