牛至油对仔猪肠道微生物菌群的影响

研究证明，牛至油的抗菌机理独特，不产生抗药性．且与抗生素及合成的化学抗菌药物无交叉抗药性。并可以提高猪生产性能和替代饲用抗生索，但牛至油对仔猪肠道微生物菌群的影响未见报道。该试验通过饲料中添加牛至油观察其对仔猪肠道微生物菌群的影响．为进一步开发和利用牛至油提供一定的理论依据。     

Influence of cornual insemination on endometrial damage and microbial flora in the bovine uterus

The objectives were to determine effects of cornual insemination on endometrial characteristics and uterine bacterial flora. Forty cows were assigned randomly (10/group) to each of the following treatments: 1) control--no uterine manipulation; 2) uterine body insemination--deposition of the inseminate at the internal cervical os; 3) cornual insemination--one-half of inseminate deposited into each uterine horn anterior to the internal bifurcation and 4) cornual insemination plus endometrial biopsy--insemination into each uterine horn and trauma induced by endometrial biopsy. Animals were slaughtered and reproductive tracts were removed 5 d after treatment. Bacterial populations of the uterine lumen were evaluated by both flushings and swabbings of each horn. Treatment did not influence the presence of luminal bacteria as determined by flushing or swab samples. Gross endometrial characteristics were quantitated in all tracts. Characteristics considered were total endometrial surface area, discolored regions that appeared to be distinctly darker than the remaining portion of the endometrium and obvious surface damage. Discolored regions were evaluated as both total areas and percentage of endometrium. Treatment did not influence total or percent discolored areas. Microscopic evaluation of these tissues revealed increased edema when compared with nondiscolored regions but no disruption of the luminal epithelium was found. Surface damage was found only in the biopsied treatment group. Observation of the endometrium revealed that extensive regeneration occurred by 5 d after treatment. The data suggest that cornual insemination does not result in uterine trauma or bacterial presence 5 d after breeding, and the endometrium is capable of regeneration after trauma during estrus.     

载铜硅酸盐纳米微粒对不同品种断奶仔猪粪便中微生物菌群影响的研究

<正>仔猪腹泻是一种由多种病原因素引起的疾病,常见的有仔猪黄痢、白痢及早期断奶腹泻综合症等,发病率高,严重影响仔猪的生长发育,甚至引起死亡,给畜牧业造成巨大损失。病原性细菌感染是引起仔猪下     

Studies on the microbial flora of the large intestine of the horse by continuous culture in an artificial colon

The use of a continuous culture artificial colon is described in experiments with caecal and dorsal and ventral colonic contents from the horse. The activity of the system was measured by volatile fatty acid estimation and the percentage of hay and cellulose digested was calculated. The vitamin B₁₂ (cyanocobalamin) content of the continuous culture and the amount synthesised by individual bacteria isolated from the system and directly from the colonic content, was estimated.     

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.     

饲用抗生素对肠道微生物影响的研究

1饲用抗生素的起源和促生长效果1.1起源和发展饲用抗生素是在药用抗生素的基础上发展起来的。Stockstad等(1949)发现,链霉素(strepfomyces)发酵过程中得到的代谢产物,可以促进鸡只快速生长。Whitehill于1950年说明此代谢产物中含有的金霉素具有促生长效果。Jukes等(1950)试验证     

Quantitative composition of the gastrointestinal flora in the young pig]

Studies were conducted into the quantitative composition of the gastro-intestinal flora in clinically intact store pigs. The methods are described in greater detail, followed by presentation of results. In the discussion particular reference is made to literature. Conclusions are drawn regarding the topographic distribution of the various germ groups in the gastro-intestinal tract of the store pig.