Some experimental surgical techniques on the alimentary tract of young pigs.

The paper describes the surgical techniques used in the preparation of gastric, intestinal and caecal fistulae, intestinal re-entrant fistulae, gastric pouches and Thiry-Vella loops. A total of 189 pigs were used in the study ranging from 1 h to 16 weeks of age. All procedures were carried out under cyclopropane/oxygen anaesthesia.     

Gram-negative anaerobes in the intestinal flora of pigs

A differential count of the gram-negative, anaerobic, non sporeforming bacteria in different segments of the pig intestinal tract was performed in 2 groups of pigs. Seventy-seven strains were identified, belonging to 6 groups: Sphaerophorus necrophorus, anhemolytic Sphaerophorus spp., Bacteroides (Eggerthella) spp., Fusobactenum spp., Veillonella/Acidaminococcus spp., and Peptostreptococcus elsdenii. The characters of these groups are described, and quantitative data on their occurrence in a group of normal porkers and a group of pigs with experimental swine dysentery are given.     

Prevention of the growth of Salmonella infantis in chicks by the flora of the alimentary tract of chickens

The effect on the growth of Salmonella infantis in the caeca of chicks pre‐treated with either the cultured flora of the alimentary tract of an adult chicken, horse faeces or bovine rumen fluid was studied. Forty 2‐d‐old chicks were inoculated orally with S. infantis. Pre‐treatment with the cultured flora of the alimentary tract of an adult chicken as well as fluids from the alimentary tract prevented the colonisation of the caeca by S. infantis. The numbers of salmonella isolated from the caeca of all chicks with no pre‐treatment were more than 10⁷ per g. Bovine rumen fluid and horse faeces were ineffective in preventing the caeca of chicks being colonised by S. infantis.     

健康猪肠道菌群的分离培养与耐药性分析

为了解猪肠道正常菌群的耐药性及其临床意义,从健康猪新鲜粪便中,分别采用麦康凯琼脂、MRS增菌液与HYA琼脂、MRS增菌液与TYP琼脂分离大肠杆菌、乳酸杆菌和双歧杆菌,并挑取单个菌落进行形态染色观察、生化鉴定及药敏试验。结果发现,大肠杆菌对克林霉素和红霉素有较强耐药性,乳酸杆菌对诺氟沙星有较强耐药性,而双歧杆菌对诺氟沙星、氯霉素有较强耐药性,提示正常菌群的耐药性可能是影响肠道病原菌感染及其治疗效果的不可忽视因素。     

Influence of the gut flora and of some growth-promoting feed additives on nitrogen metabolism in pigs. I. Studies in vitro

Nine growing pigs (10–40 kg) were cannulated either in the duodenum or ileum or caecum and fed a dry-milk powder diet. These pigs were used as donors of fresh intestinal contents for short (4 h) incubation experiments. From the incubations of duodenal contents, it appeared that the bacterial activity was not important. In consequence, the antibiotic effects of Virginiamycin and Spiramycin were also negligible. During incubations of ileal contents, eventually supplemented with free amino acids, on the other hand, 20–30% of the amino acids were degraded by the flora either by deamination, with formation of ammonia, or by decarboxylation with formation of amines: histamine, putrescine, cadaverine, tyramine, phenylethylamine. Cadaverine, the decarboxylation product of lysine, was the most important amine detected. Both processes were severely decreased when the antibacterials Virginiamycin (50 p.p.m.), Spiramycin (50 p.p.m.), Carbadox (50 p.p.m.) and copper sulphate (200 p.p.m.) were present during the incubation of the ileal contents. The fermentation of caecal contents was characterized by a pronounced production of ammonia, slightly inhibited by Virginiamycin and Spiramycin.Testing the amino acid decarboxylation activity of the dominant flora (E. coli, S. faecalis, L. acidophilus and L. fermenti) in the small intestine of the pig, it was found that E. coli is the main producer of amines in the small intestine of pigs.We conclude that the gut flora of pigs has a measurable negative influence on protein digestion in the small intestine and that this effect can be overcome by feeding nutritional antibacterials.     

猪和兔胚胎胃肠道菌群的初步研究

微生物由于个体小、数量大、繁殖快和适应性强而广泛分布于自然界。国内外的微生物学和微生态学文献一直认为:世界上没有无菌的人和动物,只有健康母体的子宫和胚胎的消化道内是无菌的[1,6]。在养猪生产实践中,时常见到新生仔猪在出生后当日的1~3 h内,随着胎粪排出立即出现严重腹泻、下痢,重者成窝迅速死亡(冬季多见),如在接产时,投服“绿宁”等微生态制剂即可控制了本病的发生。这种新生仔猪急性下痢启示我们,是否在胚胎发育阶段胃肠道就已存在某些正常菌群,由于出生后温度、湿度等环境条件骤然改变,正常原籍菌群失去平衡而导致腹泻或下痢。…