Bhandari S K, Xu B, Nyachoti C M, Giesting D W, Krause D O
Department of Animal Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2 Canada.
J Anim Sci. 2008 Apr;86(4):836-47. doi: 10.2527/jas.2006-822. Epub 2008 Jan 11.
Enterotoxigenic Escherichia coli is a major problem in the swine industry and results in scouring, increased mortality, and poor performance in the period immediately postweaning. The traditional way to control this problem is to include subtherapeutic antibiotics in the feed, but this is no longer acceptable to consumers; thus, alternatives to antibiotics are needed. One of the supplements that has been effective in reducing scouring in the absence of antibiotics is animal blood products produced from the rendering process. This is also becoming a problem because of concerns regarding the transfer of transmissible spongiform encephalopathies to humans from animals. In this research, we investigated the effects of spray-dried porcine plasma (SDPP), a Bacillus subtilis direct-fed microbial (DFM), a blend of organic acids, and sweeteners on E. coli-induced scouring. A total of 108 pigs of approximately 17 d of age were assigned to 6 treatments, with 3 pigs per pen, in 2 blocks, with each block having 3 replicates. The 2 blocks were initiated approximately 2 mo apart, because a sufficient number of pigs were not available that met our inclusion criteria in the first block. Diet 1 was a negative control containing no antibiotics (NC). Diet 2 was the positive control and included the same ingredient composition as NC except that antibiotics (110 mg/kg of chlortetracycline, 110 mg/kg of sulfamethazine, and 55 mg/kg of penicillin) were added (PC). Diet 3 was equal to the NC, but with a B. subtilis probiotic (DFM). Diet 4 was the NC to which SDPP was added. Diet 5 was the NC plus a combination of SDPP and DFM (SDPP + DFM). Diet 6 was the NC plus a combination of supplements, including SDPP and a blend of organic acids, DFM, and a sweetener (Blend). At 24 d of age, the pigs were experimentally infected with 6.3 x 10(9) cfu/mL of E. coli K88. All pigs were euthanized 7 d after infection and tissues were obtained for analysis. There were no significant differences among treatments for ADG, ADFI, G:F, plasma urea nitrogen, alpha-acid glycoprotein, tumor necrosis factor-alpha, intestinal ammonia, pH, or VFA. However, the PC and DFM treatments showed decreased (P < 0.05) scours at 24 h postinfection compared with the NC, SDPP, and SDPP + DFM diets. Mortality in the NC treatment, which did not contain antibiotics, was greater (P < 0.05) than in the other treatments. Terminal restriction fragment length polymorphism analysis of the 16S rDNA genes of digesta showed a greater incidence (P < 0.05) of Bacteroidetes in the PC and DFM diets than in the NC diet. When SDPP and DFM were included in the diet, the incidence of Bacteroidetes was also greater than in the NC diet (P < 0.05).
产肠毒素大肠杆菌是养猪业中的一个主要问题，会导致腹泻、死亡率增加以及断奶后 immediately 期生长性能不佳。控制这个问题的传统方法是在饲料中添加亚治疗剂量的抗生素，但这已不再为消费者所接受；因此，需要抗生素的替代品。在不使用抗生素的情况下，一种有效减少腹泻的补充剂是来自提炼过程的动物血液制品。由于担心可传播性海绵状脑病从动物传播给人类，这也正成为一个问题。在本研究中，我们调查了喷雾干燥猪血浆（SDPP）、枯草芽孢杆菌直接投喂微生物（DFM）、有机酸混合物和甜味剂对大肠杆菌引起的腹泻的影响。总共108头约17日龄的仔猪被分配到6种处理中，每栏3头猪，分2个区组，每个区组有3个重复。2个区组相隔约2个月开始，因为在第一个区组中没有足够数量符合我们纳入标准的猪。日粮1是不含抗生素的阴性对照（NC）。日粮2是阳性对照，除添加了抗生素（110mg/kg金霉素、110mg/kg磺胺二甲嘧啶和55mg/kg青霉素）外，其成分与NC相同（PC）。日粮3与NC相同，但添加了枯草芽孢杆菌益生菌（DFM）。日粮4是添加了SDPP的NC。日粮5是NC加上SDPP和DFM的组合（SDPP + DFM）。日粮6是NC加上包括SDPP、有机酸混合物、DFM和甜味剂的补充剂组合（混合物）。在24日龄时，仔猪经实验感染6.3×10⁹cfu/mL的大肠杆菌K88。感染7天后对所有仔猪实施安乐死并获取组织进行分析。各处理在平均日增重（ADG）、平均日采食量（ADFI）、料重比（G:F）、血浆尿素氮、α-酸性糖蛋白、肿瘤坏死因子-α、肠道氨、pH或挥发性脂肪酸（VFA）方面没有显著差异。然而，与NC、SDPP和SDPP + DFM日粮相比，PC和DFM处理在感染后24小时的腹泻情况有所减少（P < 0.05）。不含抗生素的NC处理的死亡率高于其他处理（P < 0.05）。对消化物16S rDNA基因的末端限制性片段长度多态性分析表明，PC和DFM日粮中拟杆菌的发生率高于NC日粮（P < 0.05）。当日粮中包含SDPP和DFM时，拟杆菌的发生率也高于NC日粮（P < 0.05）。
