热应激对动物体内蛋白质周转代谢的内分泌途径的影响

本文讨论了高温条件下机体内分泌激素对蛋白质合成、分解的影响,试图从内分泌角度解释高温对动物体蛋白质沉积的影响机理.     

A miniature lighted stylet for fast oral endotracheal intubation in rabbits

Efficient oral endotracheal intubation of laboratory animals is a challenging technique in veterinary research. This study introduces a miniaturized lighted stylet for rabbit intubation. An experiment with repeated measures on two factors was used to assess the feasibility and efficacy of this method. The first factor compared stylet intubation vs. laryngoscopic intubation. The second compared three practitioners, one with prior experience and two without. Success rates on the initial attempt were not statistically different (χ² = 2.46, P = 0.12). The time difference between methods was significant (F = 41.007, P < 0.001), although the effect of practitioners was not (F = 1.038, P = 0.365). The mean ± SD of the intubation time, combining results from the three practitioners, was 20.34 ± 17.15 s for the stylet method and 57.58 ± 64.21 s for the laryngoscopic method. The results of this study demonstrate that lighted stylet intubation is efficient, robust, and independent of practitioner experience.     

溶氧因素对冬虫夏草摇瓶培养的影响

对冬虫夏草菌丝体摇瓶培养中影响溶氧的主要因素进行分析。通过测定不同摇床转速、装液量、封口方式下摇瓶培养后的菌丝得率,并对其进行单因素分析,选择单因素较优水平,然后进行3因素正交试验。结果表明,最适宜溶氧条件为摇床转速140r/min、装液量50%、封口采用无菌培养容器封口膜;各因素影响培养的显著性依次为摇床转速、装液量、封口方式;不同摇床转速下对有效成分含量测定显示,摇床转速对虫草多糖及虫草酸含量影响不显著。     

豆粕粉碎粒度与蛋白质体外消化率的关系研究

将过3．0mm、2．0mm、1．2mm和0．8mm孔径筛片的蒸炒豆粕（测定的几何平均粒度分别为2565μm、529μm、449μm、334μm和210μm）进行体外消化,研究豆粕粒度与蛋白质消化率的关系,结果表明：粒度为449μm组的粗蛋白消化率最高,比2565μm、529μm和334μm组分别提高了10．75％、4．43％和1．37％（P〈0．01）;比210μm组提高了0．17％（P〈0．05）;粒度为449μm组和334μm组的干物质消化率（分别为68．95％,68．89％）较高,分别比2565μm和529μm组提高了（3．52％,3．44％）和（8．14％,8．06％）（P〈0．01）;粒度为449pm的豆粕的赖氨酸、精氨酸、胱氨酸、甘氨酸、谷氨酸、天门冬氨酸、丙氨酸、酪氨酸和脯氨酸的消化率均高于其他粒度组。     

鹌鹑肌肉肌苷酸含量和鹑肉保鲜时间的研究

用纸层析法测定鹌鹑肌肉提取液中的肌苷酸含量,实验结果表明:1.鹌鹑性别不同的肌苷酸含量(平均值):雌鹑为5.557μM/g(肉);雄鹑为5.274μM/g(肉),差异不显著(p>0.05)。2.两组不同日龄鹌鹑胸肌肌苷酸含量(平均值):35日龄为5.739μM/g,70日龄为4.941μM/g,差异极显著(p<0.01)。3.鹌鹑不同部位肌苷酸含量,胸肌明显高于腿肌,腿肌的肌苷酸含量平均值仅为胸肌的60.51％,差异极显著(p<0.01)。4.不同条件保存鹑肉时,随着时间的延长,肌肉中的肌苷酸均降解,降解速度,低温(0℃)较室温缓慢。5.测定肌肉中肌苷酸的含量可作为衡量鹌鹑肌肉鲜度的一项有用的指标。     

大蒜素对断奶仔猪生长发育及其周围环境的影响

选用 10 8头 2 0日龄健康无病的杜× (长×大 )三元杂交断奶仔猪 ,按血缘、体重、性别一致原则随机分为 2组 ,每组设 3个重复。各组试验猪基础日粮一致、饲养管理条件一致 ,并由同一饲养员饲养。对照组饲喂带有抗生素的饲料 ;试验组在饲料中添加 2 5%大蒜素 2 0 0g t,试验期18d。结果表明 ,与对照组比较 ,试验组日增重提高 16 5% (P <0 0 5) ,料重比降低 13% (P <0 0 5) ,采食量无显著差异 ,未有试验猪发病 ,粪便颜色比对照组浅 ,粪便表面蚊蝇量较少 ,说明大蒜素对仔猪具有促生长作用 ,同时还具有抑菌和杀菌、减少仔猪发病率、驱除蚊蝇、改善舍内外环境等功效 ,从而提高了经济效益 ,是一种极具有开发价值的中草药添加剂     

法系獭兔血液中AKP活性与体尺、体重性状的关系

对20只40日龄法系獭兔和20只68日龄法系獭兔（公、母各半）血液中AKP活性进行了测定，并分析了40日龄与68日龄法系獭兔血液中AKP活性与体重、体长、胸围的相关性。结果表明：40日龄时法系獭兔血液中AKP活性高于68日龄；日龄相同时，公兔活性显著高于母兔（P＜0.05）；40日龄AKP活性与体重有较为密切的关系，其他相关则不显著。     

益生菌产表面活性剂研究进展

生物表面活性剂是由微生物代谢过程中产生的具有表面活性的生物化合物,大多具有抗细菌、真菌、支原体和病毒的特性以及抗粘附的功能。由益生菌产的生物表面活性剂,除具备上述功能,还在安全性方面具有独特优势,因此在预防和治疗某些疾病方面具有广阔的应用前景。本文针对产生物表面活性剂的益生菌的种类、筛选、产物的制备分离及应用等方面做一综述。     

Ameliorative Effects of Melatonin against Hydrogen Peroxide‐Induced Oxidative Stress on Boar Sperm Characteristics and Subsequent In Vitro Embryo Development

Melatonin, the major secretory product of the pineal gland, scavenges a variety of reactive oxygen and nitrogen species in vivo and in vitro, indicating that melatonin is a potent function as an antioxidant. The objective of this study was to investigate the effect of melatonin in the presence or absence of hydrogen peroxide (H₂O₂) on sperm characteristics (motility, viability, survival rate, membrane integrity, lipid peroxidation (LPO) and mitochondria activity) and also to examine the developmental rates to the blastocysts stage of porcine oocytes fertilized in vitro with semen treated with or without melatonin (100 nm ) in the presence or absence of H₂O₂ (250 μm ). The sperm were treated with melatonin in the presence or absence of H₂O₂ for 3, 6, 9 and 12 h at 37°C and then analysed for the sperm characteristics. The porcine embryos were produced by in vitro maturation and in vitro fertilization (IVM/IVF) using semen treated with or without melatonin (100 nm ) in the presence or absence of H₂O₂ (250 μm ) for 6 h. The semen characteristics, including motility, viability, survival rate, membrane integrity and mitochondria activity, were higher in the groups that were treated with melatonin in comparison to other groups, irrespective of incubation periods. Malondialdehyde levels in control, melatonin and melatonin + H₂O₂ groups were lower than H₂O₂ only group. A positive correlation was shown among motility, viability, survival rate and membrane integrity, but a negative correlation was observed between LPO and the other evaluation methods. The developmental rates to blastocysts of IVM/IVF porcine oocytes fertilized by semen treated with melatonin were significantly increased compared with any other groups, with the cell number of blastocysts shown to have a similar trend to the developmental rates. These results demonstrate that melatonin can improve the semen characteristics during in vitro storage and support the developmental ability of IVM/IVF embryos in pigs.