肠道菌群对动物免疫的影响

1肠道菌群及其分布 1．1肠道正常菌群的概念 在动物体内环境中通常有一层微生物或微生物层，在正常情况下即动物处于健康状态时，并未表现异常或致病现象，称这一层微生物为正常菌群或固有菌群和原籍菌群。这些菌群是动物机体内环境中不可缺少的组成部分，对动物宿主是有益无害的。     

Changes of resistance of enteric bacteria in mice given tetracycline in drinking water.

Tetracycline given to mice via their drinking water for long periods changed the gram-negative enteric flora and increased the minimal inhibitory concentration of tetracycline for Proteus and Escherichia coli in the feces.     

液态饲料对超早期隔离断奶仔猪肠道微生物区系的影响

试验选用平均体质量为(2.63±0.15)kg、(14±2)日龄的断奶仔猪(云南地方撒坝猪)20头,随机分为对照组和试验组2组,进行32d对比试验。研究了液态饲料对超早期断奶仔猪肠道微生物区系的影响。结果表明,液态饲料能显著促进超早期断奶仔猪肠道内乳酸杆菌生长,同时显著降低大肠杆菌含量(P<0.05)。     

甘露寡糖对肉鹑肠长度及肠道菌群的影响

选取240只1日龄肉鹑随机分成4组,每组设4个重复,每个重复15只肉鹑。其中第1组为对照组,饲喂基础日粮,第2~4组为试验组,在基础日粮中分别添加0.5%、1.0%2、.0%的甘露寡糖(MOS)。进行为期50日龄的饲养,分别于35日龄和50日龄采样。试验结果表明,1.0%和2.0%MOS可显著增加35日龄肉鹑小肠长度和十二指肠长度(P<0.05)。1.0%和2.0%MOS组35日龄肉鹑空肠长度和回肠长度显著长于对照组和0.5%MOS组(P<0.05)。各处理组35 d肉鹑空回比均高于对照组,但未达到统计学差异水平(P>0.05)。日粮中添加MOS对50日龄肉鹑肠长度的影响无明显规律,各处理组之间无显著差异(P>0.05)。日粮添加0.5%、1.0%2、.0%MOS可显著降低35日龄和50日龄肉鹑回肠内大肠杆菌的数量(P<0.05),随着日粮MOS添加量的增加,回肠内大肠杆菌数量逐渐下降,且1.0%和2.0%MOS添加组回肠内大肠杆菌数量显著低于0.5%MOS添加组(P<0.05)。日粮添加0.5%、1.0%、2.0%MOS可显著提高35日龄和50日龄肉鹑回肠内乳酸杆菌的数量(P<0.05),随着日粮MOS添加量的增加,回肠内乳酸杆菌数量逐渐升高,且2.0%MOS添加组35日龄肉鹑回肠内乳酸杆菌数量显著高于0.5%MOS添加组(P<0.05)。     

芽孢杆菌对宝石鲈生长和肠道菌群的影响

<正>1试验材料1.1试验幼鱼来源及驯养宝石鲈幼鱼取自山东省淡水水产研究所良种室,初始体重(31.48±1.56)g,初始体长(9.43±0.26)cm。试验幼鱼先在温室内水泥池内驯养14d,每天投喂饲料3次,分别在8:30、13:30和17:00。1.2试验饲料试验饲料为在基础饲料中添加1‰的芽孢杆菌(1011CFU/g),每克饲料含1×108个芽孢杆菌,连续投喂40d。试验饲料和基础饲料加工成粒径2.5mm的颗粒饲料。每组设置3个重复,基础饲料的营养组成见表1。     

Effect of drinking water chlorination on Campylobacter spp. colonization of broilers

The main source for Campylobacter spp. transmission from the environment to broiler chickens is still unclear. One implicated reservoir for the organism has been untreated broiler drinking water. This study was conducted with broilers first using experimental conditions (isolation units) and second under commercial conditions. We compared the rate of intestinal colonization in chickens provided 2 to 5 parts per million (ppm) chlorinated drinking water in relation to the frequency of colonization in chickens given unsupplemented drinking water. No significant difference (P > 0.05) was detected in isolation frequency or level of Campylobacter spp. colonization in birds provided chlorinated drinking water and control birds provided water without supplemental chlorine. In the isolation unit experiments, 86.3% (69/80) of the control and 85.0% (68/80) of the treated birds were colonized at levels corresponding to an average of 10(5.2) and 10(5.1) log colony-forming units (cfu) Campylobacter spp./g of cecal contents, respectively. Additionally, two sets of paired 20,000 bird broiler houses, with and without chlorination (2-5 ppm chlorine), were monitored in a commercial field trial. Effectiveness of chlorination was judged by prevalence of Campylobacter spp. in fecal droppings (960 samples) taken from the flocks in treated and control houses. Birds from the control houses were 35.5% (175/493) Campylobacter spp. positive, while 45.8% (214/467) of the samples from the houses having chlorinated drinking water yielded the organism. Chlorination of flock drinking water at the levels tested in this study was not effective in decreasing colonization by Campylobacter spp. under commercial production practices presently used in the United States.     

长期铝暴露对大鼠肝脏功能的影响

旨在探讨长期铝暴露对大鼠肝脏损伤及其功能的影响,为防制其对动物肝脏器官的危害提供理论依据。48只4周龄雄性Wistar大鼠随机分为4组,分别于饮水中添加0,64.18,128.36,256.72mg/kg体重AlCl3.6H2O溶液建立长期铝暴露大鼠模型,试验期120d。断头处死大鼠,检测血清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)活性及血清和肝脏中谷胱甘肽过氧化物酶(GSH-PX)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果表明,随染铝剂量的增加,各染铝组血清ALT、AST活性及肝脏MDA含量显著高于对照组(P<0.01、P<0.05);染铝组肝脏GSH-PX活性显著低于对照组(P<0.01),SOD活性呈先升高后下降趋势,低剂量组高于对照组,高剂量组显著低于对照组(P<0.01)。说明长时间铝暴露可增强肝脏脂质过氧化反应,降低抗氧化能力,引发氧化损伤,进而影响肝脏功能。     

复合菌剂及酸化剂对玉米秸秆青贮有氧暴露后的影响

为探讨复合菌剂和酸化剂对玉米秸秆青贮有氧稳定性及有氧暴露期间微生物数量、pH值、粗蛋白、干物质量的影响,以玉米秸秆为青贮原料,设置3个处理:对照组、复合菌剂组、复合菌剂+酸化剂组.青贮90 d.有氧暴露1、3、7、11 d分别取样测定微生物数量、pH值、粗蛋白、干物质量.结果显示,与对照组相比,复合菌剂组、复合菌剂+酸...     

Effect of long-term administration of a prostacyclin analogue (beraprost sodium) on myocardial fibrosis in Dahl rats

Beraprost sodium (BPS) is an orally active prostacyclin analogue. The effects of BPS on the heart, including coronary circulation improvement, myocardial and vascular protection and anti-fibrosis effect on myocardium interstitium, have previously been demonstrated. However, the effects of BPS on hemodynamics, cardiac function and myocardial contractility in patients in the hypertrophic phase have not been clarified. Therefore, in the present study, the effects of BPS under long-term administration were investigated using the hypertension model of salt-sensitive Dahl rats. Six-week-old Dahl rats were divided into three groups, an 8% high salt diet group treated with BPS (BPS group), an untreated 8% high salt diet group (HHF group) and an untreated 0.3% low salt diet group (Control group), and observations were conducted until 17 weeks of age. In the BPS and HHF groups, the survival rates after 11 weeks of high salt diet intake were 87.5% and 47.1%, respectively (p<0.05). At 17 weeks of age, the atrial systolic peak velocity/early diastolic peak velocity and heart weight index of the BPS group decreased significantly compared with the HHF group (p<0.05). The HHF group exhibited significantly more severe myocardial fibrosis mainly in the endocardial layer of the left and right ventricles compared with the BPS and Control groups (p<0.05). In the present study, long-term BPS administration preserved diastolic function and prevented myocardial interstitial fibrosis in the non-compensatory phase. The results of the present study suggest that BPS is effective for treatment of hypertensive cardiac hypertrophy.     

Effect of adding superphosphate to the drinking water on the fertility of dairy cows.

Mean serum inorganic phosphorus concentrations of cows in an infertile dairy herd of 170 cows in the Hunter Valley increased from less than 4.5 mg/100 ml to greater than 5.8 mg/100 ml after defluorinated superphosphate was added to their drinking water at the rate of 2.5 kg/450 1 once weekly from September, 1976. The first service pregnancy rate increased from 36.5% to 63.2%, the mean calving to conception interval decreased from 109 days to 85 days and the number of cows culled each year for infertility fell from 15 to 5. The pasture fed to the milking cows contained on average greater than 17% crude protein, greater than or equal to 0.39% phosphorus, greater than or equal to 9 ppm copper and 38--46 ppm manganese according to the dominant species. The Ca/P ratio ranged from 2 to 5.5:1. Of these, only the Ca/P ratio and the manganese concentrations appeared to be abnormal.     

The determination of a gross utilization of 15N-lysine in laboratory rats. 1. Experiment with normal intestinal flora (without antibiotic supplement)]

Wistar rats of a live weight of about 100 g were divided into 14 groups (5 animals/group). The rations given supplied the animals with 75%, 100% and 125% lysine, which brought about a moderate growth of the animals of approximately 2 g/animal and day achieved by limited feeding. The 3 lysine levels mentioned could be achieved by lysine supplements (L-lysine-HCl) for the following rations: barley (B), wheat (W), and wheat gluten (WG). For isolated soybean protein (assay protein) (S) the lysine levels 100% and 125% and for soybean meal (SM) the levels 116% and 125% could only be achieved. A control group with whole egg ration (W) (with its natural lysine content of 125% of the requirement) were also tested as comparison. During the 10-day period of the main experiment all 14 rations were supplemented with 0.5 g 15N-lysine (alpha amino group, 95% labelled with 15N). The N balance could only be significantly improved by lysine supplements in the rations B, W and SM with the lysine level of 125%. The biologic value of the protein sources was in rations B and WG also significantly improved by the highest lysine supplement. 15N excess (15N') from the deaminated 15N lysine was excreted with diet B rich in crude fibre mainly in faeces (more than 15% of the intake) and only about 10% in urine. With the diets without native crude fibre the excretion quota changed in favour of urine. The following 15N' amounts in per cent of 15N' intake from lysine were excreted in urine and faeces: B 75 = 31.3, B 100 = 30.9, B 125 = 28.0, W 75 = 24.3, W 100 = 32.2, W 125 = 32.6, GW 75 = 18.3, WG 100 = 24.2, WG 125 = 28.1, S 100 = 39.4, S 125 = 50.4, SM 116 = 34.9, SM 125 = 32.9, W 125 = 19.1. 15N excretion in urine and faeces increased in comparable relations in 6 cases of lysine increase levels only. Gross utilization of lysine can only conditionally be quantified by 15N labelled lysine supplement.     

Effect of drinking water on animal health: toxicologic health risks

To avoid health risks in farm animals it is necessary to limit the intake of unwanted chemical compounds via air, feed or drinking water. The basis for this procedure are experimental results of Veterinary Toxicology, after which acceptable daily intakes can be estimated. A health risk is not present, if those limits are not exceeded. Risks may not only occur as an impairment of health itself but as well as a reduction of yield of food producing animals (body growth, production of meat and fat, fertility, milk and egg production). In addition the cumulation of unwanted compounds in tissues, which are used for the production of food of animal origin, is of great importance for the limitation of daily intakes of those environmental pollutants. Following the results of toxicological experiments in the target animals "Toxicological Drinking Water Standards for Animals" can be established.     

发酵中草药对断奶仔猪生长性能及肠道菌群的影响

试验研究日粮中添加发酵中草药对松辽黑猪断奶仔猪生长性能和肠道菌群的影响.试验选择(35±1)d的松辽黑猪断奶仔猪54头,随机分为3组,每组3个重复,每个重复6头猪.对照组仔猪饲喂基础日粮,试验Ⅰ组饲喂基础日粮+0.5％发酵中草药添加剂,试验Ⅱ组饲喂基础日粮+0.5％不发酵中草药添加剂.预试期5d,正式试验期30 d.结...