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41.
The aim of this study is to investigate the dynamic gut microbial diversity in weaning swine after administering feed supplemented with probiotic bacteria that specifically inhibit the activity of quorum molecules. Initially, the universal quorum molecule autoinducer‐2 (AI‐2) bioassay results indicated that AI‐2 activity was profoundly inhibited in enterohemorrhagic Escherichia coli (EHEC) O157:H7 in the presence of Lactobacillus acidophilus strain 30SC cell extract, although the growth of EHEC was not affected. Based on plate counting results, bacterial community analysis revealed a specific reduction in coliforms compared to the control, whereas the population of lactobacilli increased in weaning swine in in vivo trials. Supplementation with L. acidophilus strain 30SC did not affect the counts of other communities, such as total aerobes and yeast/mold. In addition, PCR‐denaturing gradient gel electrophoresis analysis showed a significant difference in the 16S rRNA gene products after administering L. acidophilus strain 30SC. Selected bands were sequenced, and most of them were identified as uncultured bacterium clones or a Lactobacillus‐ and Bifidobacterium‐specific community. Therefore, our results indicate that quorum‐quenching probiotic bacteria can significantly modulate the gut microbiota of swine and these beneficial effects can contribute to the improvement of performance and health in the gastrointestinal tract of weaning pigs.  相似文献   
42.
瘤胃源益生菌对小鼠生长和生理特性的影响   总被引:1,自引:0,他引:1  
试验旨在对筛选出的6种瘤胃源益生菌进行小鼠试验,以期为其在畜禽养殖业的进一步开发和利用提供参考依据。选取5周龄雄性昆明小鼠56只,随机分为7组:生理盐水对照组、解淀粉芽孢杆菌Lw-J21组、枯草芽孢杆菌Lw-K16组、乳酸菌Lw-R35组、产蛋白酶菌Lw-D48组、产纤维素酶菌Lw-X21组和酵母菌Lw-JM70组,试验组每天以0.2 mL/10 g体重剂量连续灌胃42 d,对照组灌喂相同剂量的生理盐水,比较并分析灌胃不同益生菌对小鼠体重、肠道菌群数量、脂肪积累量、免疫器官指数和血糖降解能力等的影响。结果显示,与对照组相比,解淀粉芽孢杆菌Lw-J21和产纤维素酶菌Lw-X21组小鼠体重增加明显(P>0.05),同时可显著减少小鼠体内的脂肪积累(P<0.05)。乳酸菌Lw-R35和产纤维素酶菌Lw-X21组小鼠肠道中的乳酸菌和总厌氧菌数量均显著或极显著增多(P<0.05;P<0.01)。各益生菌组小鼠脾脏指数和胸腺指数均有显著或极显著提高(P<0.05;P<0.01),且可不同程度提高小鼠血糖的调节能力。综上所述,用筛选出的6种天然益生菌饲喂小鼠可改善其肠道微生态环境、免疫器官指数和血糖调节能力等。  相似文献   
43.
本试验旨在研究饲粮中添加植物乳杆菌(Lactobacillus plantarum)和非淀粉多糖(NSP)复合酶对断奶仔猪生长性能、粪便微生物菌群及血清指标的影响,从而达到代替抗生素的目的。试验采用单因素完全随机设计,选择28日龄健康断奶仔猪192头,平均体重为(7.15±0.36)kg,随机分为4个组,每组6个重复,每个重复8头猪。对照组(CT组)饲喂在基础饲粮中添加40 mg/kg杆菌肽锌的饲粮;试验组分别饲喂在基础饲粮中添加1 g/kg植物乳杆菌(PT组)、1 g/kg NSP复合酶(ZT组)、1 g/kg植物乳杆菌+1 g/kg NSP复合酶(PZT组)的饲粮。试验期35 d。结果表明:1)各组间断奶仔猪的试验末重、平均日增重、平均日采食量及料重比均无显著差异(P0.05)。2)各组间断奶仔猪粪便中乳酸菌数量、大肠杆菌数量及乳酸菌/大肠杆菌均无显著差异(P0.05)。但与对照组相比,PZT组断奶仔猪粪便中乳酸菌数量和乳酸菌/大肠杆菌有增加趋势(0.05≤P0.10),大肠杆菌数量有降低趋势(0.05≤P0.10)。3)各组间断奶仔猪的血清生化指标、免疫指标均无显著差异(P0.05)。由此可知,饲粮中复合添加植物乳杆菌和NSP复合酶可促进肠道菌群平衡,有益于仔猪健康生长,从而达到替代抗生素的目的。  相似文献   
44.
益生素在欧鳗养殖中的应用试验   总被引:1,自引:1,他引:0  
在欧鳗日粮中添加2‰益生素饲料添加剂,其增重率试验组比空白对照组高出9个百分点,饲料效率试验组比空白对照组高出7个百分点。  相似文献   
45.
益生菌制剂作为饲料添加剂,在维护畜禽机体肠道健康、菌群平衡以及营养生理方面发挥着极其重要的作用。一方面,益生菌制剂能够替代部分抗生素,为实现畜禽养殖过程中的"减抗"目标,开辟了一条优质、安全、绿色的道路;另一方面,益生菌制剂能够调控肠道生理结构和改善肠道屏障完整性,进而缓解畜禽养殖中的"亚健康"状况。本文围绕益生菌制剂的种类与作用,益生菌制剂对畜禽肠道免疫、应激、疾病的调控机制,益生菌制剂的发展前景进行阐述,为开发更多益生菌制剂的产品提供理论支撑。  相似文献   
46.
2个系列试验研究小麦日粮添加非淀粉多糖酶制剂对雏鸡生长及血液中血糖、尿酸和某些激素水平的影响。试验1将7日龄雏鸡72羽随机分为3组,即小麦基础日粮组、小麦日粮加0.15%浙江酶-1组和小麦日粮加0.15%赤峰酶组。试验2将7日龄雏鸡248羽,随机分为8组,即玉米基础日粮组、小麦基础日粮组、小麦日粮加0.1%、0.2%、0.5%浙江酶-2组和小麦日粮加0.1%、0.2%、0.5%芬兰酶组。试验1结果表明,和小麦组相比,添加0.15%浙江酶-1组雏鸡增重显著提高(P<0.05),料重比下降但不显著(P>0.05);而添加0.15%赤峰酶组增重提高,料重比下降,但均未达到显著(P>0.05)。试验2结果表明,和小麦日粮组相比,添加浙江酶-2各组雏鸡增重提高9.3%~15.7%(P<0.01),料重比降低6.3%~10.8%(P>0.05);添加芬兰酶各组雏鸡增重提高6.2%~9.7%(P<0.05),料重比降低4.2%~13.3%(P<0.05);添加酶各组和玉米组相比,雏鸡增重无明显差异。试验1和试验2血液指标测定结果表明,小麦日粮添加酶制剂可使雏鸡T4、IGF-1水平显著提高(P<0.05),对T3、胰岛素、血糖和尿酸含量未发现明显影响(P>0.05),提示酶制剂可以通过影响机体的代谢激素促进雏鸡生长。  相似文献   
47.
The objective of this experiment was to test the probiotic Efinol®L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz). For the transportation, fish were distributed in 18 plastic tanks, of which nine contained the Efinol®L (10 mg L−1; probiotic treatment) and the remaining had no probiotic (control treatment). Transport lasted 24 h and three different boxes of each treatment were sampled at 3, 12 and 24 h. Up to the 12-h sampling period, no significant difference in the survival was observed; on the other hand, survival was higher at the end of the transport (24 h) in the probiotic treatment. No significant difference was found in dissolved oxygen and temperature between treatments. Conductivity, pH and alkalinity increased along the transport, but without a difference between treatments. Ammonia increased in all treatments, although it was significantly lower in the probiotic group at 24 h. Cortisol levels were significantly higher in all transported fish when compared with the basal values. At 24 h, cortisol levels in control fish were significantly higher than those in the probiotic treatment. With the observed results, we are able to conclude that the probiotic Efinol®L is efficient during cardinal transport, lowering the mortality and helping maintain water quality possibly by lowering metabolic wastes.  相似文献   
48.
This experiment was carried out to evaluate the effects of the probiotic, Lactobacillus acidophilus , on the growth performance, haematology parameters and immunoglobulin concentration in African catfish Clarias gariepinus fingerling. Two experimental diets were formulated to contain 35 g kg−1 crude protein and 10 g kg−1 lipids accordingly and fed three times daily for 12 weeks to 25 C. gariepinus fingerlings per fibreglass tank in 12 replicates each. The control diet was prepared with no probiotic supplementation whereas the second diet was prepared supplemented with a probiotic, L. acidophilus , containing about 3.01 × 107 colonies/g of diet. The results show that growth performance [specific growth rate (SGR) and relative growth rate (RGR)], nutrient utilization [protein efficiency ratio (PER) and feed conversion ratio (FCR)] and survival were significantly ( P <0.05) higher in fish maintained on the probiotic-supplemented diet compared with those on the control diet. Haematology parameters (packed cell volume, haemoglobin, erythrocyte sedimentation rate, red blood cell and white blood cell, total serum protein, Ca2+, Mg2+, Cl, glucose and cholesterol) and total immunoglobulin concentrations were also significantly better in fish fed the probiotic-supplemented diet than in the control. Although the water quality parameters monitored were better in the fish fed the probiotic-supplemented diet than in the control, the parameters were not significantly different ( P >0.05). From the results of this experiment, we conclude that L. acidophilus can be used as a probiotic agent in African catfish culture, to enhance fish health, survival and better feed efficiency and growth performance.  相似文献   
49.
We evaluated the effects of Bacillus cereus, as an additive in water and feed, on the gut microbiota and immunological parameters of Nile tilapia (Oreochromis niloticus) fingerlings. Experiments were performed in tanks and net cages respectively. Experiment 1: Tilapia were housed in tanks for 42 days, and Bcereus was added to the water at 1.0 × 104 cfu mL?1 (Treatment 1) and 1.0 ×105 cfu mL?1 (Treatment 2) weekly. For the control, no probiotic was added. Experiment 2: Tilapia were housed in cages for 42 days, and the feed was supplemented with Bcereus at 1.0 × 107 cfu g?1 (Treatment 1) and 1.0 × 108 cfu g?1 (Treatment 2) weekly. For the control, no probiotic was added. Each treatment contained three replicates, with 50 male tilapias per replicate. The fish from the probiotic treatments in both tank and cage experiments had significantly higher serum lysozyme and peroxidase activities than the control. In the cage experiment, alkaline phosphatase and total superoxide dismutase activities in tilapia were significantly higher in probiotic treatments compared with the control. The results of polymerase chain reaction‐denaturing gradient gel electrophoresis showed that B. cereus supplementation in the feed and water affected the autochthonous gut bacteria community of tilapia and stimulated various potentially beneficial bacteria. Therefore, B. cereus, as a water or feed additive, could enhance the immune status and affect the gut microbiota of tilapia. Bacillus cereus was more effective as a feed supplement rather than a water additive for enhancing the immune status of tilapia.  相似文献   
50.
Fish are always susceptible to a wide variety of deadly pathogens which cause a huge loss in aquaculture industries. In this investigation, we have demonstrated the in vivo probiotic efficiency of Bacillus sp. MVF1 (GenBank Acc. No. KP256503) in Labeo rohita challenged with pathogenic strain of Aeromonas hydrophila (MTCC 1739). To check the probiotic potential of the selected bacterial strain, fish were divided into four groups: control, D1, D2 and D3. A total of 100 days (70 days probiotic feeding + 71th day sampling and 28 days challenged test + 29th day sampling) of feeding trial was conducted. To establish the probiotic potential of Bacillus sp. MVF1, certain haematological parameters (haemoglobin, total erythrocyte and leucocyte count), serum biochemical parameters (total protein, albumin and globulin), immune parameters (serum lysozyme and total IgM levels) and hepatic stress profile (malondialdehyde production, superoxide dismutase and catalase activity) have been measured. Our results demonstrated that red blood cell number, white blood cell number and haemoglobin content were much higher in D2 group fish compared to other groups and control fish. Similarly, total protein contents, albumin concentration, globulin concentration, lysozyme activity and IgM production were also recorded to be highest in D2 group fish. This finding clearly indicated the probiotic potential of Bacillus sp. MVF1 in L. rohita. Furthermore, our results also demonstrated that 1 × 107 CFU g?1 feed (D2) provides better immunity compared to 1 × 105 (D1) and 1 × 109 (D3). Due to beneficial effects, the bacterium Bacillus sp. MVF1 might be useful in aquaculture industries to reduce the disease susceptibility.  相似文献   
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