Effects of zinc oxide and Enterococcus faecium SF68 dietary supplementation on the performance, intestinal microbiota and immune status of weaned piglets

The objective of this study was to determine the effects of zinc oxide (ZnO) and the probiotic Enterococcus faecium SF68 (Cylactin) dietary supplementation on the performance, intestinal microbiota and immune parameters of the weaned piglet reared under commercial conditions. The diets were devoid of antibiotic growth promoters (AGP). Two hundred and eight crossbred piglets were allocated to a 2 x 2 factorial experiment involving two levels of zinc oxide supplementation (0 or 3100 mg ZnO/kg feed), and two levels of E. faecium SF68 supplementation (0 or 1.4 x 10(9)CFU/kg feed (Cylactin ME10)). The diets were offered ad libitum for 20 days post-weaning. Piglet performance was assessed by calculating average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) on a pen basis. In addition, components of the distal ileal digesta, tissue-associated and mesenteric lymph node (MLN) bacterial populations were enumerated and serum immunoglobulin G (IgG) and intestinal immunoglobulin A (IgA) concentrations were determined on days 6 and 20 post-weaning. Regression analysis was used to determine the relationship between the bacterial populations at the different sites. Supplementation of the post-weaning diet with either ZnO or E. faecium SF68 did not affect piglet performance. E. faecium SF68 did not affect gastrointestinal bacterial populations but did tend to reduce serum IgG (P<0.1) on day 20. Zinc oxide reduced anaerobic (P<0.05) and tended to decrease lactic acid (P<0.1) bacterial translocation to the MLN, and tended to increase intestinal IgA concentration (P<0.1) on day 20. Generally, luminal bacterial populations were found to be poor predictors of tissue-associated or MLN populations. ZnO and E. faecium SF68 dietary supplementation were ineffective under these trial conditions. Further investigations into the possible immunomodulator role of dietary ZnO are warranted.     

Lactobacillus GG does not affect D-lactic acidosis in diarrheic calves, in a clinical setting

D-lactate, produced by gastrointestinal fermentation, is a major contributor to metabolic acidosis in diarrheic calves. Lactobacillus rhamnosus GG survives gastrointestinal transit in the neonatal calf and does not produce D-lactate. To determine whether this probiotic reduces gastrointestinal D-lactate production or severity of diarrhea or both, 48 calves (mean, 11 days old; range, 2-30 days) admitted to the clinic for treatment of diarrhea were randomly allocated to 2 groups. The experimental group was given Lactobacillus rhamnosus GG (1 x 10(11) cfu/d) PO, dissolved in milk or oral electrolyte solution, in addition to clinic treatment protocols; the other group served as a control. Serum and fecal samples were obtained at admission and at 24 and 48 hours after initial administration of Lactobacillus rhamnosus GG. All samples were analyzed for D- and L-lactate by using high-pressure liquid chromatography. Feces were also analyzed for pathogens, Lactobacillus rhamnosus GG recovery, and dry matter. D-lactic acidemia (>3 mmol/L) was present in 37/48 calves at admission. Lactobacillus rhamnosus GG was recovered in the feces of 13 experimental calves and 0 control calves 24 hours after administration. No difference in serum or fecal D- or L-lactate between the groups was detected at any time point. After therapy, D-lactic acidosis was absent at 48 hours in all but 1 calf. No relation between fecal pathogen (viral, bacterial, or protozoal) and degree of D-lactic acidosis was observed. The reduction in mortality and greater fecal dry matter in Lactobacillus rhamnosus GG-treated calves was not statistically significant.     

微生态制剂促生长机理及其在畜牧生产上的应用

介绍了微生态制剂的概念、发展历程、组成和作用、抗病促生长机理以及微生态制剂在畜牧业生产上的应用,提出了微生态制剂应用过程中应注意的问题,并对微生态制剂在畜牧业生产上的应用前景作了展望。     

益生素对断奶仔猪生产性能和腹泻率的影响

本试验选用35±2日龄的PIC五元杂交配套系断奶仔猪45头,将其随机分成3个试验组,即试验1组、试验2组和对照组,在试验组仔猪日粮中分别添加0.1%和0.3%的复合益生菌制剂,旨在研究益生素对断奶仔猪生产性能的影响。试验结果表明,益生素对断奶仔猪的生产性能有良好的促进作用,且腹泻率有所降低。     

Microbial intervention for better fish health in aquaculture: the Indian scenario

Aquaculture has evolved as the fastest growing food-producing sector and developed as an important component in food security. To keep a sustainable growth pattern, health management strategies must go beyond antibiotics and chemotherapeutics, which create resistant bacteria and immunosuppression in the host. Besides development of drug resistant bacteria and pathogens, the adverse effect of antibiotics is caused by their influence on the aquatic microflora, and the retention of harmful residues in aquatic animals. On the other hand, the microbes with their unique structure and cell wall components can trigger immunity, and thus exposure plays an important role in the evolution. Microbial intervention through an environmentally friendly approach is an alternative method of health management. India is endowed with a bounty of varied climatic conditions, microbial diversity and fish fauna and aquaculture systems offering challenges in biological and environmental pursuits. Producing about 4.4% of world’s fish and ranking third in global fish production, India trades about 2.4% in global fish market with the annual export earning being over $1311 million. Use of microbes for beneficial purposes is increasingly recognized as a valuable input for sustainable and responsible aquaculture. Microbial intervention in aquaculture can be broadly water/environment based through bioaugmentation, biostimulation, biocontrol measures, or (to generate) host response through probiotics, immunostimulants, and vaccines. Also, application of molecular methods such as polymerase chain reaction (PCR) and nucleic acid techniques are making increasing inroads into aquatic microbiological research in India. This paper elucidates all these aspects of microbial intervention in aquaculture, high-lighting Indian research and accomplishments.     

益生素添加水平对断奶獭兔肠道免疫力的影响

[目的]研究不同益生素添加水平对断奶獭兔肠道免疫能力的影响。[方法]选择80只体重相近的35日龄的健康断奶獭兔,按公母各半随机分为4个组(I、Ⅱ、Ⅲ、Ⅳ组),分别饲喂添加0、0.1、0.2和0.4 g/kg水平益生素的饲粮,预试期7 d,试验期60 d。试验结束后测定腹泻率及十二指肠、回肠与直肠的p H和SIg A含量。[结果]在饲料中添加益生素对断奶獭兔的腹泻率、平均日增重与料重比均有影响显著(P0.05);其中Ⅲ组的日增重最高、料重比及腹泻率最低,Ⅲ组的日增重比I组升高10.96%,Ⅲ组料重比和腹泻率分别比I组降低7.37%及59.44%;肠道环境p H随益生素添加水平的升高先降低后回升,但只有Ⅱ与Ⅲ组的盲肠环境p H发生了显著变化(P0.05),与I组相比分别低了3.03%与4.43%;回肠与十二指肠的SIg A含量不受益生素添加水平的影响(P0.05),Ⅳ组的空场SIg A含量较I组高8.84%(P0.05)。[结论]断奶獭兔基础日粮中添加适宜的益生素可以降低腹泻率,影响其肠道环境与提高肠道免疫屏障,最佳添加水平为0.2 g/kg。     

益生菌混合培养富集锌条件优化研究

[目的]优化益生菌混合培养富集锌的条件.[方法]以青春双歧杆菌ys01、德氏乳杆菌保加利亚亚种1.148 0和嗜酸乳杆菌ysh2混合培养富锌.通过单因素试验和中心组合试验对富锌条件进行优化.[结果]最佳富锌培养条件为:低聚果糖10 g/L、Zn2+ 0.41mg/ml、蛋白胨12.2 g/L、初始pH 6.0、接种比例3∶2∶1、接种量4.6％、培养时间72 h.在该条件下,青春双歧杆菌ys01、德氏乳杆菌保加利亚亚种1.1480和嗜酸乳杆菌ysh2混合菌体锌的含量为550μg/g.[结论]以试验所得富锌混合菌体制备的富锌酸奶发酵剂具有良好的发酵性能..     

Fermented Milk–Starch and Milk–Inulin Products as Vehicles for Lactic Acid Bacteria

Formulations using cassava starch or inulin plus milk were fermented with three different lactic acid bacteria (LAB) strains: Lactobacillus plantarum D34, Lactobacillus sp. SLH6, and Streptococcus thermophilus ST4. Growth and acidification were followed in 3% powdered milk (M3), 3% milk–6% starch (M3-S6), and 3% milk–6% inulin (M3-In6). D34 and SLH6 growth was enhanced by starch in M3-S6, when compared to the count (CFU/ml) obtained in M3. Growth of all strains was promoted by inulin. All fermented products showed LAB counts of 8.0 log or higher. Carbohydrate utilization was in agreement with growth and acidification results. The highest increase in CFU in rat feces was observed in M3-S6 fermented with ST4; the D34 fermented product also increased CFU but SLH6 did not, either with starch or inulin. This suggests that ST4 and D34 strains provide a good choice to ferment the proposed formulations in order to obtain a marked improvement of natural intestinal flora.     

微生态制剂在鲟鱼工厂化养殖中的应用

循环水工厂化养殖过程中由于饲养的高密度和丰富的饵料投入会产生大量代谢污染物,随之也带来了养殖排放废水对环境的污染,长期以来存在氨氮、亚硝酸盐总量不断积累的问题,影响鲟鱼品质和产量。微生态制剂是从天然环境中筛选出来的微生物,具有促生长、无毒副作用,能消除养殖水体中的氨氮、亚硝酸盐、硫化氢等有害污染物,维持养殖系统中微生物的生态平衡,改善水质及水体环境。利用微生态制剂对养殖水体进行调控,对养殖鲟鱼实行全程质量控制管理,生产出无公害、无污染的优质鲟鱼产品。     

有机肥腐熟剂腐菌酵素的示范试验

为了验证腐菌酵素的作用,进行了有机肥发酵试验和对多种作物的多点试验示范。结果证明：腐菌酵素不仅能够缩短有机肥发酵腐熟的时间,还能补充土壤益生菌、抑制土传病害、增加农作物产量、改善农产品品质,具有广阔的推广前景。