摘要
The gastrointestinal tract of calves is sterile at birth, and intestinal microorganisms are introduced from fecal, vaginal and environmental microbiota. The balance of the intestinal ecosystem of calves can be altered in farming systems due to separation from their mothers, feeding with milk replacers and elimination of the benefits of cows’ milk, inadequate colostrum intake, stressful situations and use of antibiotics. Such practices may cause morbidity and mortality of young calves which can be related to economic losses. Periodic administration of a probiotic inoculum of bovine origin may favor establishment of a stable and balanced intestinal microbiota, which would improve the health of the calves. The viability and number of microorganisms inoculated is vital because the suggested minimum level (SML) of bacteria to produce beneficial effects is 106 CFU/ml. A technique that is currently being implemented to maintain the viability of probiotics is encapsulation, which consists of retaining the microorganisms within a porous gel matrix or within a semipermeable membrane containing a liquid core. In our study, we describe a new technique to produce alginate-starch macrocapsules, with the aim of producing probiotic macrocapsules to ensure bacterial viability during storage, and to facilitate administration of the inoculum to young calves with feed. To this end, we used the strain Lactobacillus casei DSPV 318 T, a probiotic inoculum of bovine origin, and it was evaluated by two formulations for conformation of the capsules: one of sodium alginate (10 g/l) and another of sodium alginate (5 g/l) + corn starch (5 g/l). These mixtures were dispersed into molds of 1 and 2 ml, placed at −20 °C, and, once frozen, submerged in a solution of CaCl2 (0.1 M) for polymerization of alginate to maintain their shape and size. The capsules containing of 5 g/l of alginate +5 g/l of starch had the highest cellular count, and the incubation of the capsules in culture media for 9 h increased the bacterial concentration. Viability of cells was maintained at the SML for 2 mo by coating the capsules with chitosan and refrigerating at 4 °C. This was reflected in a final product with a high concentration of probiotic accessible for artificial rearing of calves, with a sufficiently long expiration time, and with a size similar to the feed starter pellet, which allowed it to be mixed homogeneously with the feed which was fed to the calves.
摘要译文
牛犊的胃肠道是无菌的出生时，和肠道微生物从粪便，阴道和环境微生物引入。犊牛肠道生态系统的平衡可以耕作制度改变，由于从他们的母亲分离，用代乳的牛奶的好处，消除喂养，初乳摄入不足，紧张的情况下，并使用抗生素。这种做法可能导致发病的年轻牛犊这可能与经济损失和死亡。牛来源的益生菌种菌的周期性给药可能有利于建立一个稳定和平衡的肠道菌群，这将改善所述小腿的健康。接种微生物的活力和数量是至关重要的，因为细菌的建议最低水平（SML）产生有益的影响为10 SUP 6 / SUP CFU /毫升。这是目前正在实施，保持益生菌的生存能力封装的技术，其由内的多孔凝胶基质或内包含液体芯的半透膜保留的微生物。在我们的研究中，我们描述了一种新的技术，以产生藻淀粉大包囊，以生产益生菌大包囊以保证在储存过程中的细菌存活力的目的，并促进接种物施用到年轻犊牛用饲料。为此目的，我们使用了应变干酪乳杆菌DSPV 318 T，牛来源的益生菌种菌，藻酸钠1（10克/升）和另一海藻酸钠（5克/升）的玉米淀粉（5克/升）：它是由两种制剂为胶囊剂的构象进行评价。这些混合物被分散到1和2ml模具，设置在1 M），用于藻酸盐的聚合来维持它们的形状和大小。含有的淀粉藻酸盐5g / l的5g / l的胶囊具有最高的细胞计数，并在培养基中9小时胶囊的孵育增加细菌的浓度。细胞的生存力通过用壳聚糖胶囊及冷藏于4℃保持在SML为2个月。这反映在最终产品有高浓度的益生菌可访问犊牛人工饲养，具有足够长的截止时间，并用一个大小相似的进给起动机沉淀，这使得它可以均匀地将其供给到小腿的进料混合。
L.P. Soto[a]; L.S. Frizzo[a]; E. Avataneo[a]; M.V. Zbrun[a]; E. Bertozzi[a]; G. Sequeira[a][b]; M.L. Signorini[c]; M.R. Rosmini[a][b]. Design of macrocapsules to improve bacterial viability and supplementation with a probiotic for young calves[J]. Animal Feed Science and Technology, 2011,165(3-4): 176–183