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.     

蛋鸡血浆VLDL浓度二世代双向选择对体脂沉积的影响

以雅发褐壳蛋鸡为素材,在零世代和一世代双向选择的基础上,应用血浆极低密度脂蛋白(VLDL)浓度对体腹脂性状继续进行双向选择,比较了高低脂系间体组成的差异,并研究了中后期血浆VLDL浓度与上述性状的相关程度,进一步探讨了血浆VLDL浓度的选择效应。结果表明:二世代母鸡中后期高脂系体重较高(P<0.05),血浆VLDL浓度与体重呈极显著的表型相关(P<0.01)和中等程度的正遗传相关。62周龄高脂系的腹脂率显著高于低脂系(P<0.05),说明运用血浆VLDL浓度经过二个世代的双向选择,使产蛋鸡中后期体重降低,且对腹脂沉积产生了一定的影响。     

羊、鸡抗鼠脂肪细胞膜抗血清对大鼠体脂与生长性能的影响

应用提取的鼠脂肪细胞膜分别免疫羊和鸡 ,所产生的抗血清用于 Wistar大鼠被动免疫。实验 1: 组腹腔注射羊正常血清 , 组腹腔注射羊抗鼠脂肪细胞膜抗血清 ,剂量均为 1m L /只 ,连续注射 4 d。结果表明 ,羊抗鼠脂肪细胞膜抗血清免疫促进了大鼠体增重 ,降低了体脂沉积 ,与对照组相比 ,7周末体重增加 6 .35 % (P<0 .0 5 ) ,饲料摄入增加6 .85 % (P<0 .0 1) ,料重比 (F/G)提高 4 5 .0 0 % (P<0 .0 5 ) ;肾周、附睾、网膜脂肪垫重量分别降低 2 3.92 % (P<0 .0 5 )、34.4 5 % (P<0 .0 5 )、0 .98% ,脂肪总量降低 2 0 .92 %。实验 2 :1组腹腔注射鸡正常血清 ,2组腹腔注射鸡抗鼠脂肪细胞膜抗血清 ,剂量均为 1m L/只 ,连续注射 4 d。结果表明 ,鸡抗鼠脂肪细胞膜抗血清免疫对大鼠的生长发育产生了不利影响 ,7周末 ,免疫大鼠平均体重较对照组减少 4 0 g(P<0 .0 5 ) ,饲料摄入显著降低 (P<0 .0 1) ;对体脂的沉积和血液中 TG和 FFA的影响没有规律 ,且无统计学意义     

Association of hyponatremia and hyperglycemia with outcome in dogs with congestive heart failure

Objective: To evaluate plasma sodium and glucose concentrations in dogs with congestive heart failure (CHF) prior to treatment and evaluate the differences between survivors and non‐survivors. Design: Retrospective study. Animals: Fifty‐nine dogs with CHF prior to receiving cardiac medication. Interventions: None. Measurements and main results: The mean plasma sodium concentration in dogs with CHF was below the reference range (144–156 mmol/L) and significantly lower (P=0.009) in non‐survivors (141±6 mmol/L) compared with survivors (147±4 mmol/L). The mean plasma glucose concentration was above the reference range (76–117 mg/dL) and significantly higher (P=0.004) in non‐survivors (128±52 mg/dL) compared with survivors (100±13 mg/dL). Forty‐four percent of non‐survivors had concurrent low plasma sodium and high plasma glucose concentrations, whereas no survivors had both abnormalities (P<0.0001). Conclusions: Lower plasma sodium and higher plasma glucose are associated with a worse outcome in dogs with CHF.     

虾蛄蛋白浆对河蟹摄食和生长影响的研究

分别用虾蛄蛋白浆替代饲料中2%和4%的鱼粉,并以乌贼膏为对照,研究其对河蟹摄食和生长的影响。结果表明,饲料中添加虾蛄蛋白浆对河蟹的诱食作用与乌贼膏相当,但摄食量显著高于乌贼膏组。此外,虾蛄蛋白浆还具有明显的促进河蟹脱壳生长的作用,其作用机制可能与其中氨基酸、小肽、胆固醇等含量丰富有关。     

微波等离子处理对脲醛胶性能的影响

脲醛树脂胶粘剂是木材加工领域应用最广泛的胶粘剂,在保障其胶合性能的前提下降低脲醛胶的甲醛释放量是社会关注的焦点和难点。通过试验,研究不同的微波等离子处理方法对脲醛树脂胶粘剂的固化时间、适用期、胶合强度、游离甲醛含量的影响。试验结果表明:等离子处理对脲醛树脂胶粘剂的固化时间和适用期的影响不明显;合适的等离子处理条件可以改善脲醛胶的胶合性能;与未经等离子处理脲醛胶相比,等离子处理后脲醛胶的游离甲醛含量显著降低。     

哺乳动物精清诱导排卵活性蛋白质研究

在动物的精清里包含一些与动物生殖生理活动密切相关的活性蛋白和多肽。驼科动物的双峰驼、美洲驼、羊驼和澳洲考拉等哺乳动物精清中含有类似促性腺激素释放激素(GnRH)作用的活性蛋白质,诱导排卵因子(ovulation inducing factor,OIF),它能引发外周血液中促黄体素(LH)峰浓度的出现和诱发母畜排卵。OIF被认为是一种新的生物活性蛋白质或潜在的新型激素。甚至报道在牛等自发排卵动物以及人精清中也存在类似的活性蛋白。这类因子的发现对于哺乳动物生殖生理及繁殖的深入研究具有重要的意义,有助于动物克服繁殖障碍及繁殖疾病的治疗等。     

过瘤胃胆碱对黔北麻羊羔羊生长性能及血浆生化指标的影响

本试验旨在研究补饲过瘤胃胆碱(RPC)对黔北麻羊羔羊生长性能及血浆生化指标的影响.选取体况良好、体重相近的4月龄黔北麻羊羔羊20只随机分为对照组[(15.89±1.66) kg]和试验组[(15.30±1.86) kg],每组10只.对照组饲喂基础饲粮,试验组补饲10 g/d的RPC.试验期40 d,其中预试期10 d,正试期30 d.结果表明,补饲RPC:1)显著提高干物质采食量全期平均值(P＜0.05),显著降低料重比(P＜0.05);2)对干物质、粗蛋白质、粗脂肪、中性洗涤纤维的表观消化率无显著影响(P＞0.05),但可显著提高酸性洗涤纤维、粗灰分的表观消化率(P＜0.05);3)可显著提高食入氮、吸收氮和沉积氮(P＜0.05);4)对血浆超氧化物歧化酶活性以及丙二醛、葡萄糖、尿素氮、极低密度脂蛋白、甘油三酯、总胆固醇、肌酐浓度的全期平均值均无显著影响(P＞0.05).在本试验条件下,补饲10 g/d的RPC可提高黔北麻羊羔羊生长性能,但对血浆生化指标没有显著影响.     

离心除精浆对提高冷冻精液品质的作用

采用离心洗涤法去除精浆后,对精液进行冷冻处理。发现:1、除精浆精子冻后的活率、Ⅰ类顶体率和精子畸形率与未除精浆组存在显著差异(P<0．05);2、除精浆使稀释后精液精浆中GOT和LDH活性明显升高(P<0．05)。从平衡后到解冻后各组GOT和LDH活性都呈上升趋势。但除精浆试验组比未除精浆试验组上升缓慢;3、除精浆试验组精子的穿卵率、卵内平均精子数都显著高于未除精浆试验组(P<0．05);4除精浆离心洗涤液用生理盐水和脱脂乳-卵柠液．两者之间无显著差异(P>0．05)。