The effects of diet and age on serum complement system activity in goat kids

Thirty new born male kids were allotted into three groups to evaluate the effects of diet and age on complement system activity in serum. After the colostrum feeding period, the control group (C) received a commercial milk replacer; the CLA group received 20 g/kg milk replacer DM of conjugated linoleic acid; and the GMK group was fed with goat milk. The kids were fed colostrum for 2 days and then either milk replacer or goat milk from days 3 to 60. Blood samples were taken at 1, 10, 20, 30, 40, 50 and 60 days of age. The complement system activity was higher (P < 0.05) in the GMK group throughout the whole experiment through alternative pathway. C kids did not present complement activity at any time. CLA group complement activity was statistically higher than that of C kids from 30 to 60 days, through alternative pathways. In conclusion, the milk replacer formula should be reformulated because it did not induce any complement system activity in the first two months of life.     

共轭亚油酸对产蛋鸡血液生化指标的影响

选择96只30周龄依沙褐壳商品蛋鸡作为试验动物,按单因子设计随机分成4个处理,每处理6个重复,每个重复4只鸡,分别饲喂添加0%、0.5%、1%和2%共轭亚油酸的日粮,以研究CLA对产蛋鸡血液生化指标的影响。结果表明,蛋鸡日粮添加CLA促进T3、T4、Ins和E2的分泌,但降低Cor的分泌;血清中TG、TC、HDL-C和LDL-C含量随着日粮CLA添加水平的提高而降低,但HDL-C/LDL-C却随CLA添加水平的提高而增加,各添加组分别比对照组提高了2.72%、5.84%和6.61%;血清中ALP、P5 和Ca2 均随CLA添加有降低趋势,各处理组分别比对照组降低了1.2%、10.9%、19.29%,10.0%、6.67%、16.0%(p<0.05)和3.11%、17.62%(p<0.05)、19.04%(p<0.05)。     

Evaluation of beef tallow as a natural source of conjugated linoleic acid

Cis‐9, trans‐11 conjugated linoleic acid (9c, 11t CLA) is a potential anticarcinogen that is found in higher concentrations in beef lipids. However, the effect of CLA on lipid peroxidation, which is closely related to carcinogenesis, is controversial. In this study, we determined the levels of 9c, 11t CLA contents and thiobarbituric acid reactive substances (TBARS) in the tissues of rats fed beef lipid. Sprague‐Dawley rats (male, 8 weeks old) were fed experimental diets containing 20% lyophilized beef, and 12% beef tallow or vegetable oils, for 56 days. With the exception of the brain, the tissues from the rats fed the experimental diets accumulated 9c, 11t CLA, depending on the levels of CLA in the diets. The beef tallow group showed significantly higher 9c, 11t CLA contents in all tissues examined than the other diet groups. The intake of beef lipid did not affect the TBARS levels in the rat tissues. The hepatic lipid content from the beef tallow group was lower than that from the group fed vegetable oils. These results suggest that beef is a good source of 9c, 11t CLA, and that the intake of an appropriate level of beef lipid is not hazardous to health.     

阿莫西林-克拉维酸注射剂及其在猪体内的药物动力学研究

以阿莫西林(AMO)和克拉维酸(CLA)为原料,以注射用大豆油为溶媒,成功研制出AMO-CLA注射用混悬剂。采用加温加湿试验和光加速试验对制剂进行稳定性研究,结果表明该制剂稳定性良好,AMO和CLA的相对标示量均在90%以上、样品的外观色泽、粒度、分解产物等指标均无明显变化。在药物动力学研究中,用HPLC-UV法测定在血浆中AMO和CLA的含量。血药浓度数据经3p97软件处理,静注AMO和CLA水溶液在猪体内的药物动力学过程均符合一级吸收一室模型,肌注自制AMO-CLA注射用混悬剂、辉瑞公司的AMO-CLA注射用混悬剂及单方AMO注射用混悬剂在猪体内的动力学过程均符合一级吸收二室模型,且吸收良好,半衰期长。AMO在猪体内的持效时间(C>0.3μg/mL)超过48h,缓释作用显著。自制AMO-CLA注射用混悬剂的主要动力学参数与辉瑞公司的AMO-CLA注射用混悬剂的动力学参数比较差异不显著。     

Conjugated fatty acids and methane production by rumen microbes when incubated with linseed oil alone or mixed with fish oil and/or malate

We hypothesized that manipulating metabolism with fish oil and malate as a hydrogen acceptor would affect the biohydrogenation process of α‐linolenic acid by rumen microbes. This study was to examine the effect of fish oil and/or malate on the production of conjugated fatty acids and methane (CH₄) by rumen microbes when incubated with linseed oil. Linseed oil (LO), LO with fish oil (LO‐FO), LO with malate (LO‐MA), or LO with fish oil and malate (LO‐FO‐MA) was added to diluted rumen fluid, respectively. The LO‐MA and LO‐FO‐MA increased pH and propionate concentration compared to the other treatments. LO‐MA and LO‐FO‐MA reduced CH₄ production compared to LO. LO‐MA and LO‐FO‐MA increased the contents of c9,t11‐conjugated linoleic acid (CLA) and c9,t11,c15‐conjugated linolenic acid (CLnA) compared to LO. The content of malate was rapidly reduced while that of lactate was reduced in LO‐MA and LO‐FO‐MA from 3 h incubation time. The fold change of the quantity of methanogen related to total bacteria was decreased at both 3 h and 6 h incubation times in all treatments compared to the control. Overall data indicate that supplementation of combined malate and/or fish oil when incubated with linseed oil, could depress methane generation and increase production of propionate, CLA and CLnA under the conditions of the current in vitro study.     

共轭亚油酸的来源及其生物学作用

共轭亚油酸(CLA)因具有许多生物保健功能而成为动物营养学领域的研究热点,诸如抗癌、抗动脉硬化及其提高免疫力等。CLA主要存在于反刍动物的肉及乳制品中,它主要由反刍动物瘤胃内微生物氢化多不饱和脂肪酸的中间产物,或通过内源乳腺、脂肪组织经△9脱氢酶脱氢所形成。     

c9,t11-共轭亚油酸异构体的分离纯化

为进一步研究c9,t11-共轭亚油酸的生理生化特性,需获得高纯度的c9,t11-共轭亚油酸异构体。利用假丝酵母脂肪酶两步选择性酯化可以提高c9,t11-共轭亚油酸异构体的含量。采用分子蒸馏装置来分离纯化大量样品,最后得到纯度92.2 wt%的c9,t11-共轭亚油酸。     

共轭亚油酸对猪免疫功能的影响

共轭亚油酸（Conjugated Linoleic Acid, CLA）属于多不饱和脂肪酸,是必需脂肪酸亚油酸的一组异构体。CLA 具有抗肿瘤、抗动脉粥样硬化、抗糖尿病、减少脂肪沉积、增强免疫机能和促生长等广泛的生物学作用。文章综述了共轭亚油酸对猪免疫机能的作用,为进一步开发和利用共轭亚油酸提供依据。     

反刍动物体内CLA的形成及其影响因素

共轭亚油酸（CLA）是一种主要从反刍动物脂肪及其奶产品中发现的天然活性物质.一些多不饱和脂肪酸（主要是亚油酸和亚麻酸）在反刍动物瘤胃内通过异构化和生物脱氢反应形成CLA;另外,反式油酸在动物细胞内经Δ9-脱氢酶的脱氢作用也能形成CLA.c9,t11-CLA是反刍动物脂肪中CLA的主要异构体,其在乳脂中占80%～90%,在肉中要稍低.多种自然因素,人工手段能够影响反刍动物体内CLA含量.     

植物乳杆菌对提高发酵牛乳中共轭亚油酸含量的研究

利用植物乳杆菌(Lactobacillus plantarum) LT2-6发酵添加亚油酸(LA)的脱脂牛乳,转化LA生成共轭亚油酸(CLA),以期提高发酵牛乳中的CLA含量。结果表明：LA诱导可提高发酵牛乳中的CLA产量,发酵温度37℃,CLA生成量和LA转化率为最高。加入葡萄糖、酪蛋白酶水解物,有助于植物乳杆菌LT2-6的生长和提高CLA的生成量。添加0.075％的LA,发酵24 h,43％的LA转化为CLA,发酵后牛乳中的CLA含量达到320 μg/mL,为普通发酵牛乳的5～6倍。经脂肪酸萃取和甲酯化,气相色谱检测显示生成的CLA主要为：cis-9,trans-11-CLA。