Diurnal and individual variations in bile acids in the plasma of normal dairy cows

Blood samples were collected every 2 h during a 24 h period from 6 cows of one herd and 10 cows of another herd. In a third herd 9 cows were sampled every 2 h from 6 a.m. to 8 p.m. Concentrations of total bile acids, acetoacetate, glucose and free fatty acids were determined in blood plasma. A marked difference in individual bile acid concentrations and patterns of diurnal variation was found. For most cows the highest bile acid values were observed between 2 and 6 a.m. (overall mean (+/- SD) at 6 a.m.: 104 +/- 84 mumol/l, range: 20-307 mumol/l). Fourteen cows with a bile acid value greater than 90 mumol/l at 6 a.m. ("high BA") were characterized as a group by showing a pronounced decrease in the mean bile acid concentration after morning feeding. In the group of 11 cows with a 6 a.m. bile acid value less than 90 mumol/l ("low BA") the time of day did not contribute significantly to the bile acid variation. For the "high BA" group a nearly synchronous variation between the mean values of the 3 feeding dependent parameters (acetoacetate, glucose and free fatty acids) and the mean values of bile acids was found. The within animal coefficients of correlation between bile acids and the feeding dependent parameters were significantly higher in the "high BA" group than in the "low BA" group. No direct connection was found between bile acid levels and the quantity of concentrates fed or the individual milk yield.     

自由基清除剂对香蕉水分胁迫的保护作用

本文用苯皿酸钠、ａ－生育酚和Ｖ 作为外源自由基清除剂,研究其对香蕉的抗旱保护作用结果表明,外源自由基清除剂预处理降低了干旱条件下香蕉叶片细胞的膜生和膜脂过氧化程度,延缓叶绿素、可溶性蛋白南含量的降低,表现出外源自由基保护剂对减轻干旱引起的自由基伤害,提高香蕉抗旱能力具保护作用。不同清除剂的保护效果存在差异,以ａ－生育酚效果最好。     

一起违规使用餐厨泔水喂养生猪案的评析

2017年8月,青岛市某区动物卫生监督所监督检查发现,B养殖场使用饭店泔水喂养生猪。经立案调查,违法事实确实,依据《畜牧法》《青岛市无规定动物疫病区管理条例》等相关规定,依法给予了1 000元行政处罚。本文对法律法规的适用,泔水处理联防联控及强化普法宣传教育等内容进行了思考,着重分析了泔水喂猪传播非洲猪瘟的原因,坚持疏堵结合,提升泔水处置能力,引导养殖场(户)科学养殖。     

鸡尿酸盐沉积临床病理学实验研究

将２５６只３５日龄迪卡鸡随机分为对照、高蛋白Ⅰ、高蛋白Ⅱ、高钙和肾衰组,通过人工复制尿酸盐沉积病例,对禽痛风进行临床病理学研究。结果：（１）正常鸡血浆中约有０．１０７ｍｍｏｌ／Ｌ的尿酸与大分子（蛋白质）结合,当血浆尿酸浓度升高时,结合尿酸的浓度不变,游离尿酸水平升高;（２）高蛋白饲料使饮水增多,血浆尿酸、ＮＰＮ升高（Ｐ＜０．０１或Ｐ＜０．０５）,而肾脏菊糖清除率与对照组（３．２７２μｇ／ｋｇ．ｍｉｎ－１）差异不显著（Ｐ＞０．０５）,剖检未见痛风病变;（３）日粮高钙使采食量下降,增重降低,血浆钙、尿酸、ＮＰＮ升高（Ｐ＜０．０１或Ｐ＜０．０５）,肾菊糖清除率（２．７０９μｇ／ｋｇ．ｍｉｎ－１）与对照组差异不显著（Ｐ＞０．０５）,但死亡鸡中３／１１见肾和输尿管内有较多尿酸盐沉积;（４）肾脏损害使血浆尿酸、ＮＰＮ升高（Ｐ＜０．０１或Ｐ＜０．０５）,Ｎａ＋、总蛋白降低（Ｐ＜０．０５）,肾菊糖清除率显著低于对照组（Ｐ＜０．０５）,死亡鸡中１９／２７有明显肾脏肿大、肾和输尿管内沉积大量尿酸盐。     

母猪饲粮添加甜菜碱对巴马香猪哺乳仔猪血液指标的影响

本试验旨在研究母猪饲粮添加甜菜碱对巴马香猪哺乳仔猪血液指标的影响。选取3~7胎次妊娠巴马香猪40头,随机分为2组,每组20头,单栏饲养。对照组饲喂基础饲粮,试验组在基础饲粮中添加3.5 kg/t甜菜碱。试验期为母猪配种后第3天至分娩后第21天。试验结束时,从每组随机选取10窝仔猪,每窝选取1头仔猪采血,测定血浆激素含量、抗氧化指标和游离氨基酸含量。结果表明:与对照组相比,甜菜碱组哺乳仔猪血浆胆囊收缩素(CCK)、酪酪肽(PYY)、瘦素(LEP)、丙二醛(MDA)、过氧化氢(H2 O2)和丙氨酸(Ala)含量显著降低(P<0.05),血浆鹅肌肽(Ans)、1-甲基组氨酸(1⁃MeHis)和3-甲基组氨酸(3⁃MeHis)含量显著升高(P<0.05),血浆苏氨酸(Thr)(P=0.069)、谷氨酸(Glu)(P=0.055)和肌肽(Car)(P=0.055)含量呈下降趋势,血浆亮氨酸(Leu)含量呈升高趋势(P=0.069)。综上所述,母猪饲粮添加甜菜碱可降低哺乳仔猪血浆摄食相关因子水平,减弱机体的氧化水平,改变血浆游离氨基酸含量,有利于仔猪的生长发育与机体健康。     

唇形科植物提取物对单胃动物的抗氧化作用及其机制

动物在患病、应激或特殊生理条件下,机体内会大量产生自由基,自由基与机体内的脂质、ＤＮＡ等产生反应,可对动物造成氧化损伤。唇形科植物提取物中的抗氧化物主要活性成分是酚类化合物,它和抗坏血酸及类胡萝卜素能够阻止自由基引发的氧化伤害。本文阐述了唇形科植物提取物对猪、鸡体外和体内抗氧化作用的实例与抗氧化功能,分析了其抗氧化作用机制。     

High dietary energy level stimulates growth hormone receptor and feed utilization in large Atlantic salmon (Salmo salar L.) under hypoxic conditions

This study examines how appetite and growth regulation of Atlantic salmon are affected by low dissolved oxygen (LO) and dietary digestible energy levels (DE: high [HE] vs. low [LE]). Long‐term exposure to LO resulted in a reduced feed intake, growth, digestible protein and fat retention efficiencies and increased feed conversation ratio and plasma ghrelin concentrations (p < .05) compared to high dissolved oxygen (HO). Pair‐feeding of rations based on the feed intake of the LO groups, but fed at HO, resulted in a 50% growth improvement in HE diet groups. This suggests that the poor growth under LO was not entirely caused by the reduced feed intake. Salmon adapted to LO by increased haemoglobin concentrations, while osmoregulation was affected by increased plasma chloride concentrations (p < .05). Plasma ghrelin concentration was unaffected by DE (p > .05). Growth regulation was affected by the HE diet, with increased liver and muscle growth hormone receptor ghr1 mRNA (p < .05), regardless of oxygen level. The growth depression due to low oxygen appears to be related to higher metabolic costs, while higher DE upregulates the GH‐IGF system at the ghr1 level and found to be beneficial for growth, feed intake, oxyregulation and osmoregulation under hypoxia.     

农户舍饲奶牛血清钙及游离羟脯氨酸水平测定

采用氯胺T比色法和EDTANa_2滴定法,对重庆市农户舍饲奶牛不同泌乳阶段血清中游离羟脯氨酸与血清钙的水平进行 测定,旨在调查试验条件下奶牛血钙代谢情况以及骨营养不良发生的可能性。结果显示: 在农户全舍饲条件下,血清钙含量Ⅱ组显著低于Ⅴ组、Ⅵ组,其它各组间差异不显著;Ⅰ～ Ⅵ组血清羟脯氨酸含量分别为2.32±0.37μg/ml、2.36±0.59μg/ml、2.02±0.54μg/ml、1.90±0.44μg/ml、1.98±0.45μg/ml、1.79±0.18μg/ml,Ⅰ、Ⅱ组与Ⅵ组差异极显著。采样后2-3个月内进行临床观察,血清游离羟脯氨酸水平与骨营养不良发生率呈现一致性变化。而钙磷摄入不足,比例不当是主要原因。     

脱毒百合种球生产关键技术研究

介绍了脱毒百合原种的要求、脱毒种球的生产和预防病毒病发生传播的措施等脱毒百合种球生产关键技术。