Efficacy of tiamulin as a growth promotant for growing swine

A study involving 244 pigs initially averaging 13 kg was conducted at two stations to evaluate tiamulin as a growth promotant for growing swine. In each experiment, four replicate pens of five (Exp. 1) or six (Exp. 2) pigs/pen were used to evaluate each treatment. In Exp. 1, pigs were fed 0, 11, 22 or 44 ppm tiamulin from 15 to 58 kg, then fed a nonmedicated control diet for the remainder of the experiment (to 95 kg). In Exp. 2, pigs were fed 0, 2.75, 5.5, 11 or 22 ppm tiamulin from 11 to 56 kg, followed by the nonmedicated control diet (to 95 kg). In each experiment, carbadox (55 ppm) was included as a positive control and was fed to an average weight of 35 kg, followed by the control diet. Averaged across all dietary levels, tiamulin resulted in a 14.1% improvement in gain and a 5.7% improvement in feed:gain ratio during the first 28 to 35 d of the experiment (to 30 kg). These improvements were slightly less than those resulting from the feeding of carbadox during the same period (21.5 and 6.9%, respectively). From 13 to 57 kg, pigs fed tiamulin gained 11.6% faster and 3.1% more efficiently than did controls. Over the entire experiment (13 to 95 kg), tiamulin-fed pigs gained 5.7% faster than did controls, even though the tiamulin was withdrawn at 57 kg body weight. Growth rate from 13 to 57 kg plateaued at the 11-ppm dietary level of tiamulin; whereas, feed:gain ratio plateaued at the 22-ppm level. The results indicate that tiamulin is an effective growth promotant for growing swine.     

聚乙烯聚吡咯烷酮作为生长促进剂喂鸡的效果

试验分育雏期与生长期,用以测定聚乙烯聚吡咯烷酮(PVPP)对优质肉鸡的促生长效果。育雏期选用石歧杂黄羽肉鸡3237只,按入孵时的蛋重分为大蛋群与小蛋群。试验鸡在相同的饲养管理条件下按三种处理喂养:(1)对照组喂基础日粮;(2)试验1组为基础日粮+100ppm pvpp;(3)试验2组为基础日粮+200ppm pvpp。42天育雏期的结果表明:在日粮中添加PVPP能提高雏鸡的成活率和饲料效率,以200ppm PVPP组最佳,成活率提高4.2％(大蛋群)和35.2％(小蛋群),饲料报酬提高13.6％(大蛋群)和17.1％(小蛋群)。生长期试验选用石歧杂鸡240只,层笼饲养,试验期4周(49日龄至77日龄),观察添加不同剂量PVPP(0、100、200和400ppm)的饲养效果。结果显示的生产 成绩以添加PVPP各组较好,但组间差异不显著。     

Exposure of workers to dust and bioaerosol on a poultry farm

Poultry houses are known for generating excessive dust, which originates from bedding materials, fiberglass insulations, feed, dried fecal materials, and feather particles. Dust may contain microorganisms, including endotoxins, fungi, and bacteria, that may affect living things when inhaled. Dust that contains living organisms is referred to as bioaerosol, and its particle size may range from 0.5 to 100 µm. Respirable dust, which has an aerodynamic diameter of less than or equal to 4 µm, can travel to and be deposited in the gas-exchange region of the human respiratory system. This is of particular concern because of the greater health hazard that it poses. The concentrations of respirable dust and bioaerosol measured with samplers attached to the workers (worker-exposure concentrations) were more than 3 (0.82 vs. 0.26 mg/m³) and one-and-a-half times (58.46 vs. 33.79 cfu/m³) higher, respectively, than the concentrations measured with stationary samplers indoors. The respirable dust is still below the permissible exposure limit (5 mg/m³) set by the Occupational Safety and Health Administration, but beyond the limit for animal buildings suggested by other researchers.     

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.     

Genetic relatedness of high-level aminoglycoside-resistant enterococci isolated from poultry carcasses

Approximately 46% (75/162) or poultry enterococci collected between 1999 and 2000 exhibited high-level resistance to gentamicin (minimum inhibitory concentration [MIC] > or = 500 microg/ml), kanamycin (MIC > or = 500 microg/ml), or streptomycin (MIC > or = 1000 microg/ml). Forty-one percent of the isolates were resistant to kanamycin (n = 67), whereas 23% and 19% were resistant to genramicin (n = 37) and streptomycin (n = 31), respectively. The predominant species identified was Enterococcus faecium (n = 105), followed by Enterococcus faecalis (n = 40) and Enterococcus durans (n = 8). Using polymerase chain reaction, the isolates were examined for the presence of 10 aminoglycoside resistance genes [ant(6)-Ia, ant(9)-Ia, ant(4')-Ia, aph(3')-IIIa, aph(2")-Ib, aph(2")-Ic, aph(2")-Id, aac(6')-Ie-aph(2")-Ia, and aac(6')-Ii]. Five aminoglycoside resistance genes were detected, most frequently aac(6')-Ii and ant(6)-Ia from E. faecium. Seven E. faecalis isolates resistant to gentamicin, kanamycin, or streptomycin were negative for all genes tested, indicating that additional resistance genes may exist. Phylogenetic analysis revealed that the isolates were genetically different with little clonality. These data indicate that enterococci from poultry are diverse and contain potentially unidentified aminoglycoside resistance genes.     

规模养鸡场(户)免疫失败原因及防治措施

最近一段时期，有螳规模鸡场和饲养户虽然按照要求，每年针对鸡的日龄晶种及免疫程序接种疫苗，但还是不断发生传染病，给规模养鸡场（户）造成了很大的经济损失。本人根据最近工作和实际调查情况，谈一谈规模鸡场（户）免疫失败的丰要原因和防制措施。     

Epidemiological study of an outbreak of infectious coryza on a poultry farm in Iraq

This report deals with an outbreak of infectious coryza (IC) in a Badosh, Iraq, poultry farm in 1982. It appears to be the first published report of IC in Iraq, although claims of previous occurrence of the disease have been made.     

养禽场传染病的综合性防制

禽场传染病的控制重点在于防，而现在一般所讲的防指的也是综合防制，而不是仅仅的用药、疫苗预防。一旦发生传染病，总会对经营者造成一定的经济损失，更何况如禽流感、新城疫、传支等原则上根本无法治疗。可以说，只要成功地防治好鸡病，养鸡生产就成功了一多半。做好传染病的防治工作，应从以下几方面入手。１隔离、消毒隔离工作在综合防制中占有举足轻重的地位，“隔离”在这里指的是病原微生物与生物机体（易感鸡群）隔离开，使易感鸡群远离病原微生物，使病原微生物失去感染的机会。作为鸡群的隔离工作主要有：鸡舍与鸡舍之间的隔离，…     

Contamination of Salmonella blockley in the environment of a poultry farm.

Cecal and environmental samples were collected and examined for the presence of Salmonella on a farm where a high prevalence of Salmonella blockley in chickens was observed. Of 895 cecal and 525 environmental samples examined, 242 (27.0%) and 202 (38.5%) samples, respectively, yielded S. blockley. From the analysis of plasmid profile patterns, 11 different plasmid profile patterns were found among 444 isolates, with plasmid patterns c and d the most frequent among the isolates from ceca and the environment. Salmonella blockley was isolated from environmental samples such as floor litter, walls, drinking water, waste water, dust, and soil collected when barns were occupied and was positive in drinking water, waste water, and soil when samples were collected from empty barns with occupied neighboring barns, but it was negative in all environmental samples with the exception of soil when the environmental samples were collected from empty barns with empty neighboring barns.     

Prevalence of vancomycin resistant enterococci on poultry farms established after the ban of avoparcin

Fecal samples from poultry on farms established after the ban of avoparcin (study farms) and from poultry on farms previously exposed to avoparcin (control farms) were examined for the presence of vancomycin-resistant enterococci (VRE). The samples were collected during the autumn and winter of 2001-2002. One isolate from each positive sample was selected, identified to species level, and examined for the presence of the vanA gene. The concentration of VRE and generic enterococci in the samples were also determined. In addition, the susceptibility to the ionophoric coccidiostat narasin was examined in a number of enterococcal isolates from poultry and in some enterococci of porcine origin that had not been exposed to narasin. VanA-type VRE was detected in samples from 64% of the study farms and 96% of the control farms. However, the concentration of VRE in the control samples was about six times larger than in the samples from the study farms. The minimum inhibitory concentration values for narasin differed between the poultry (1-4 mg/liter) and the porcine (0.25-0.5 mg/liter) isolates, indicating a decreased susceptibility towards narasin among enterococci from poultry.     

HACCP体系对肉鸡生产中药物残留的控制效果

在上海某大型鸡场所辖的5个肉鸡场严格按照肉鸡生产标准卫生操作规范(SSOP)程序基础之上制定并实施HACCP程序,为了验证HACCP体系的应用效果,我们以出口肉鸡场中常用的抗生素———新霉素残留为例,比较鸡场在应用HACCP程序之前和之后的药物残留情况。3月份和9月份在5个实施HACCP的鸡场和5个相同规模的对照鸡场采集肝脏样品,每个鸡场60份样品,检测新霉素残留情况。结果在实施HAC-CP的鸡场新霉素残留量由原来的0.133 mg/kg下降到0.101 mg/kg,新霉素药物残留超标率由1%(3/300)下降到0(0/300)。而同期5个未实施HACCP鸡场的2批鸡中新霉素残留量分别为0.140 mg/kg、0.134 mg/kg,超标率分别为1.3%(4/300)、1%(3/300)。由此可见HACCP程序的实施,对鸡场药物残留的控制有明显的效果。