Efficacy of thiopeptin as a growth promotant for growing barrows and gilts--a cooperative study

A cooperative study involving 280 crossbred pigs was conducted at three experiment stations (Illinois, Indiana and Kentucky) to evaluate the efficacy of the antibiotic, thiopeptin, as a growth promotant for growing pigs. At each station, two replications of barrows and two replications of gilts (four or five/pen), initially averaging 9.3 kg, were fed a fortified corn-soybean meal basal diet with 0, 5.5, 11, 22 or 44 ppm thiopeptin. The pigs averaged 41.4 kg at the end of the 56- to 57-d experimental period. Daily gain increased quandratically (505, 550, 565, 585, 590 g/d; P less than .001) and feed required per unit of gain decreased quadratically (2.32, 2.26, 2.29, 2.22, 2.22; P less than .15) with increasing levels of thiopeptin. Breakpoint analysis indicated that rate and efficiency of growth were maximized at the 14- and 22-ppm levels of thiopeptin, respectively. Averaged across all levels of thiopeptin, gain was increased by 13.4% and feed/gain by 3.2% in pigs fed the antibiotic. Responses to dietary treatment were similar at each station, with no evidence of a treatment X station interaction for gain (P = .35) or feed/gain (P = .80). Barrows and gilts performed similarly (558 vs 560 g/d, 2.26 vs 2.26 feed/gain) and there was no evidence of a sex X treatment interaction. From the results of this experiment, we conclude that thiopeptin is an effective growth promoting agent for growing swine.     

The efficacy of salinomycin as a growth promotant for swine from 9 to 97 kg

Six trials involving 586 pigs initially averaging 9 kg were conducted at three locations (two trials/location) to evaluate the effects of the dietary addition of 0, 27.5, 55, 82.5 and 110 ppm of a monocarboxylic polyether antibiotic, salinomycin, on feed intake, growth rate and feed efficiency of swine fed corn-soybean meal-based diets. Over the total trial (9 to 97 kg), quadratic improvements in gain (P less than .01) and feed:gain (P less than .04) occurred with increasing level of salinomycin, but feed intake was not affected (P greater than .25). Mean improvements for all drug levels over control values for the total trial were 4.3% for daily gain (P less than .01) and 3.4% for feed:gain (P less than .01). For the total trial, rate and efficiency of gain were optimized in pigs fed the 82.5-ppm level of salinomycin with an improvement of 5.2% in daily gain and 4.8% in feed:gain over pigs fed the control diet. The absence of any significant trial X treatment interaction suggests that the nature of the response was not dependent on differences in environment, management or other factors that existed among trial locations.     

Efficacy of tiamulin against experimentally induced Streptococcus suis type-2 infection in swine

Eighteen 4-week-old pigs were used in a study to evaluate tiamulin in drinking water for control of experimentally induced Streptococcus suis type-2 infection. Pigs in groups A and B (n = 6 pigs/group) were aerosolized with a logarithmic-growth phase culture of S suis type 2, whereas pigs in group C (n = 6 pigs) served as noninfected and nonmedicated controls. After exposure to S suis, pigs in group B were given 180 mg of tiamulin/L of drinking water for 5 days. Pigs in group B consumed more feed (P = 0.009) and gained body weight faster (P = 0.02) than did pigs in group A. Pigs in group A had higher rectal temperature (P = 0.05) for up to 7 days after S suis exposure, higher clinical sign scores (P = 0.008), higher serum cortisol concentration on days 7 and 14, higher gross lesion scores (P = 0.03), and higher microscopic lesion scores (P = 0.01) than did pigs in groups B and C. Gross and microscopic lesions in pigs of groups A and B included meningitis, pneumonia, pleuritis, pericarditis, peritonitis, and synovitis of variable severity. Streptococcus suis type 2 was recovered from tissue specimens of 2 group-A pigs and 1 group-B pig. Data indicated that tiamulin administered via drinking water significantly reduced the effects of S suis type-2 infection.     

Evaluation of tiamulin for treatment of mycoplasmal pneumonia in swine

During 3 trials, using affected pigs of various ages, tiamulin was evaluated for treatment of experimentally induced mycoplasmal pneumonia. Pneumonia was induced in respiratory tract disease-free swine by intratracheal inoculation of a lung homogenate containing Mycoplasma hyopneumoniae. Eleven days after inoculation, when more than 20% of pigs were coughing, pigs were allotted to 3 or 4 groups (n = 8 pigs each) and were given regimens of no medication or 60 mg, 120 mg, or 180 mg of tiamulin/L of drinking water for 10 days. Twenty-one days after cessation of medication, pigs were euthanatized and then were necropsied. Results obtained from the 3 trials did not indicate significant difference among treatment groups in severity of macroscopic or microscopic lesions induced by M hyopneumoniae or in detection of M hyopneumoniae by use of immunofluorescent technique. Clinical evaluations, daily gain, and feed efficiency did not differ significantly among treatment groups. In this study, tiamulin administration did not have beneficial effects in swine with mycoplasmal pneumonia.     

Effect of growth promotant usage on enterococci species on a poultry farm

The species population of enterococci isolated from four poultry houses for six grow-outs on one farm was determined. Two houses on the farm were control houses and did not use any antimicrobials, while two other houses on the farm used flavomycin, virginiamycin, and bacitracin during different poultry grow-outs. Litter, chick boxliners, feed, and poultry carcass rinses were obtained from each house and cultured for the presence of enterococci. Nine species of enterococci (Enterococcusfaecalis, E. faecium, E. avium, E. casselifiavus, E. cecorum, E. durans, E. gallinarum, E. hirae, and E. malodoratus) were identified from the study. Enterococcus faecalis was isolated more frequently from chick boxliners (n=176; 92%) and carcass rinses (n=491; 69%), whereas E. faecium was found more frequently in litter (n=361; 77%) and feed (n=67; 64%). Enterococcus faecalis (n=763; 52%) and E. faecium (n=578; 39%) were isolated most often from the farm and houses, regardless of antimicrobial treatment. Fifty-two percent of E. faecalis and 39% of E. faecium were isolated from both control (n=389 and 295, respectively) and treatment (n=374 and 283, respectively) samples. This study indicates that antimicrobial usage on this farm did not alter the resident population of enterococci.     

An ultrastructural analysis of osteochondritic growth plate cartilage in growing swine

In growing swine, ossification failure due to osteochondrosis has an incidence of nearly 100% in the distal ulna of animals at six months of age, yet the etiology of the disease is understood poorly. In this study, the ultrastructure of the chondrocyte and its pericellular matrix is analyzed in normal growth plates and in growth plates with lesions characteristic of osteochondrosis using aldehyde primary fixatives and osmium-ferrocyanide as the secondary fixative. Chondrocytes in lesion areas fail to undergo normal hypertrophic cell maturation, and they have an accumulation of rough endoplasmic reticulum, lipid droplets and mitochondria. These morphological changes are interpreted to be both variable and nonspecific for osteochondrosis. Within the pericellular matrix of chondrocytes from lesion areas, the most striking abnormality is the presence of a highly condensed matrix with an accumulation of large, irregularly shaped deposits of electron dense material. These morphological alterations are characteristic of a matrix which either is not secreted normally, or in which the highly ordered interactions of diverse macromolecules has been lost. These pericellular matrix changes have not been described in other diseases of growing cartilage. They may be significant in the failure of metaphyseal vascular penetration of the pericellular matrix which is characteristic of osteochondrosis.     

金霉素,泰妙菌素联合应用对鸡败血霉形体病的药效研究

观察了金霉素、泰妙菌素联合用药的体外抗鸡败血霉形体的作用与体内治疗鸡败血霉形体病的疗效。体外抑菌试验中,金霉素、泰妙菌素、金霉素与泰妙菌素（３∶１）合用,对鸡败血霉形体ＢＧ４４Ｔ株的最小抑菌浓度分别为２．０、０．０１６、０．０１６ｍｇ／Ｌ;棋盘法试验进一步证明,金霉素、泰妙菌素合用对鸡败血霉形体ＢＧ４４Ｔ株的ＦＩＣ指数为０．５～０．７５,两药表现有协同作用。饮水给药对实验性鸡败血霉形体病的治疗试验表明,金霉素、泰妙菌素按３∶１合用,以２００、１００ｍｇ／Ｌ剂量给药５ｄ,在死亡率、治愈率、有效率等几个指标方面优于泰妙菌素、金霉素单独给药（２００ｍｇ／Ｌ）。     

畜生禽专用抗生素妙菌素的研究进展

泰妙菌素(Tiamulin)又名泰妙灵和支原净,是由高等真菌担子菌侧耳属Pleurotus mutilus 和 Pleurotus passeckerianuus菌种的深层培养液提取的截短侧耳素(Pleuromutilin)的氢化延胡索酸盐,是双萜烯类化合物半合成的抗生素.     

Vitamin E requirement of growing swine

The vitamin E requirement of growing pigs was estimated on the basis of prevention of morphological signs of deficiency. Five groups of pigs were fed a barley-based diet low in vitamin E that contained 16 mg of DL-alpha-tocopheryl acetate equivalents/kg and .1 ppm of Se for 4 wk (depletion I). This period was followed by 7 wk of supplementation, during which the groups received 0, 15, 45, 135 and 405 mg of supplemental DL-alpha-tocopheryl acetate/kg diet. Finally, all the animals were fed the low vitamin E diet for 7 wk (depletion II). To follow the vitamin E concentration in serum and tissues, blood samples were collected and biopsies were taken from skeletal muscle, adipose tissue and the liver throughout the experiment. The peak vitamin E value was observed in the liver, followed by the adipose tissue and then skeletal muscle. The liver responded rapidly to changes in dietary vitamin E intake, whereas the adipose tissue and the skeletal muscle reacted at a slower rate. In spite of the abundant occurrence of the different vitamin E isomers in the feed, alpha-tocopherol was the main isomer detected both in the serum and in the tissues. The activity of glutathione peroxidase in serum increased with age but was independent of the serum vitamin E concentration. In the unsupplemented group all animals suffered from the vitamin E and Se deficiency syndrome (VESD) in an acute or chronic form. A total of 31 mg of DL-alpha-tocopheryl acetate/kg diet (16 mg of naturally occurring vitamin E and 15 mg as supplementation) equivalent to 2.5 IU vitamin E/g polyunsaturated fatty acids (PUFA) was enough to prevent the development of VESD. In view of the large individual variations of vitamin E concentration in target organs, and to obtain a certain safety margin for prevention of VESD in growing pigs, a supplement of 30 mg of DL-alpha-tocopheryl acetate/kg diet is recommended.     

Alternatives to antibiotics as growth promoters for use in swine production:a review

In the past two decades, an intensive amount of research has been focused on the development of alternatives to antibiotics to maintain swine health and performance. The most widely researched alternatives include probiotics, prebiotics, acidiflers, plant extracts and neutraceuticals such as copper and zinc. Since these additives have been more than adequately covered in previous reviews, the focus of this review will be on less traditional alternatives. The potential of antimicrobial peptides, clay minerals, egg yolk antibodies, essential oils, eucalyptus oil-medium chain fatty acids, rare earth elements and recombinant enzymes are discussed. Based on a thorough review of the literature, it is evident that a long and growing list of compounds exist which have been tested for their ability to replace antibiotics as feed additives in diets fed to swine. Unfortunately, the vast majority of these compounds produce inconsistent results and rarely equal antibiotics in their effectiveness. Therefore, it would appear that research is still needed in this area and that the perfect alternative to antibiotics does not yet exist.     

Alternatives to antibiotics as growth promoters for use in swine production: a review

In the past two decades, an intensive amount of research has been focused on the development of alternatives to antibiotics to maintain swine health and performance. The most widely researched alternatives include probiotics, prebiotics, acidifiers, plant extracts and neutraceuticals such as copper and zinc. Since these additives have been more than adequately covered in previous reviews, the focus of this review will be on less traditional alternatives. The potential of antimicrobial peptides, clay minerals, egg yolk antibodies, essential oils, eucalyptus oil-medium chain fatty acids, rare earth elements and recombinant enzymes are discussed. Based on a thorough review of the literature, it is evident that a long and growing list of compounds exist which have been tested for their ability to replace antibiotics as feed additives in diets fed to swine. Unfortunately, the vast majority of these compounds produce inconsistent results and rarely equal antibiotics in their effectiveness. Therefore, it would appear that research is still needed in this area and that the perfect alternative to antibiotics does not yet exist.     

抗生素对生长肥育猪生产性能和血液指标的影响

抗生素作为饲料添加剂广泛地应用 ,促进了畜牧业和饲料工业的发展 ,提高了经济效益。根据我国的国情和畜牧业的发展状况 ,抗生素将在一定的时间内在畜牧业和饲料工业中大量应用。在养猪生产中 ,猪的年龄越小 ,使用抗生素的效果越显著。抗生素对畜禽免疫机能具有一定的抑制作用 ,但抗生素对血液指标的影响报道很少。本试验的目的旨在探索抗生素对生长肥育猪生产性能和部分血液指标的影响。1　材料与方法1 1　试验动物选择平均体重为 2 0ｋｇ的三元杂 (杜大长 )商品猪 5 0头母猪和阉公猪各半。分 2 0～5 0ｋｇ和 5 0～ 90ｋｇ两段饲养。于每…     

The application of antimicrobial peptides as growth and health promoters for swine

With the widespread ban on the use of antibiotics in swine feed,alternative measures need to be sought to maintain swine health and performance.Antimicrobial peptides(AMPs) are part of the nonspecific defense system and are natural antibiotics produced by plants,insects,mammalians,and micro-organisms as well as by chemical synthesis.Due to their broad microbicidal activity against various fungi,bacteria and enveloped viruses,AMPs are a potential alternative to conventional antibiotics for use in swine production.This review focuses on the structure and mechanism of action of AMPs,as well as their effects on performance,immune function and intestinal health in pigs.The aim is to provide support for the application of AMPs as feed additives replacing antibiotics in swine nutrition.     

The application of antimicrobial peptides as growth and health promoters for swine

With the widespread ban on the use of antibiotics in swine feed, alternative measures need to be sought to maintain swine health and performance. Antimicrobial peptides (AMPs) are part of the nonspecific defense system and are natural antibiotics produced by plants, insects, mammalians, and micro-organisms as well as by chemical synthesis. Due to their broad microbicidal activity against various fungi, bacteria and enveloped viruses, AMPs are a potential alternative to conventional antibiotics for use in swine production. This review focuses on the structure and mechanism of action of AMPs, as well as their effects on performance, immune function and intestinal health in pigs. The aim is to provide support for the application of AMPs as feed additives replacing antibiotics in swine nutrition.     

规模化猪场H1亚型猪流感油乳剂灭活疫苗免疫的抗体变化动态

猪流感(Swine influenza,SI)是由正粘病毒科A型流感病毒引起的一种猪的急性、热性、高度接触性呼吸道传染病,临床上以高热、精神沉郁、食欲下降、呼吸困难为特点,可导致猪只生产性能下降,料肉比上升,增重减缓。猪流感常导致猪繁殖与呼吸障碍综合征、传染性胸膜肺炎、猪链球菌等