Efficacy of lincomycin-spectinomycin water medication on Mycoplasma meleagridis airsacculitis in commercially reared turkey poults

A field trial was conducted to compare the efficacy of a combination of the drugs lincomycin and spectinomycin (LS) with Tylan (tylosin, T) against Mycoplasma meleagridis (MM) airsacculitis in 50,320 commercially reared turkey poults in Ohio. Both drugs were administered at 2 g per gallon of drinking water for the first 5 days of life. The poults were allotted randomly to two treatment groups with 8 or 5 replicates each. Initially, 250 poults were weighed, necropsied, and examined microbiologically and grossly for airsacculitis. At 3 weeks of age, 33 poults from each replicate were randomly selected, necropsied, and examined for airsacculitis. The data indicate that LS is superior to T as an aid in the control of MM airsacculitis in poults, as reflected by fewer air-sac lesions and greater improvement in weight gain (P less than 0.05).     

The comparison of an aqueous preparation of tilmicosin with tylosin in the treatment of Mycoplasma gallisepticum infection of turkey poults.

A virulent strain of Mycoplasma gallisepticum (MG) was used to infect groups of 40 2-day-old poults kept in separate pens of 10 each. Of the six groups, three were treated with separate concentrations of tilmicosin, one was treated with tylosin, one remained untreated, and a final group was not infected and not treated. Mortality, clinical signs, and gross lesions were significantly less (P < 0.001) in the uninfected and infected medicated groups than in the infected unmedicated group. Also, the mean body weight gain of poults surviving to the end of the experiment was greater (P < 0.005) in the uninfected and infected medicated groups. MG was not recovered from the uninfected birds, and, among the infected poults, it was recovered from significantly fewer (P < 0.05) poults in the medicated groups. Serologic results were negative for the uninfected group, and there were fewer positive reactors for the infected medicated than the infected unmedicated group. In consideration of these results, tilmicosin should prove to be a useful addition to the antimicrobials in the treatment of MG infection in poults.     

Culturing anomalies associated with Mycoplasma recovered from the tissues of chicks and turkey poults experimentally infected with Mycoplasma gallisepticum or Mycoplasma gallinarum.

Tissues of mycoplasma infected chicks and turkey poults were cultured and subcultured on mycoplasma agar. Usually, colonies which grew on the agar initially inoculated could be subcultured, but sometimes they could not. At other times, colonies were not seen on the agar initially inoculated but appeared on the subcultured plate.     

Oral challenge of turkey poults with Mycoplasma iowae

Day-old poults were inoculated orally each day for 7 days with 0.2 ml of Mycoplasma iowae, strain D112, 10(8) colony-forming units/ml. Cloacal swabs were taken from each poult during the inoculation period and at selected intervals until 21 days after the last inoculation. Most poults shed mycoplasmas persistently after inoculation. Cloacal swabs from eight out of ten poults were positive at 21 days after the last inoculation. Feces of poults in the infected group were normal, and there was no significant rise in cloacal temperature. At necropsy, mycoplasmas were recovered from tissues of the respiratory tract, gastrointestinal tract, spleen, and kidney. In the gastrointestinal tract, the most frequent recoveries were from the wall of the distal portion of the small intestine, cecum, and large intestine. Recovery of M. iowae from these organs and tissues indicated infection following oral challenge.     

替米考星(Tilmicosin)对鸡败血霉形体感染的药效学

以试管二倍稀释法测定替米考星 (Tilmicosin)及对照药物强力霉素、红霉素、泰乐菌素对鸡败血霉形体的最小抑菌浓度分别为 0 .0 0 6 2 5、0 .0 2 5、0 .0 2 5、0 .1m g/ L ,进行了替米考星对鸡败血霉形体的体内药效学研究。结果 ,替米考星以 5 0、75、10 0 mg/ L 饮水给药 5 d,对实验性感染鸡败血霉形体有显著疗效 ,用药组增重均显著高于对照组 (P<0 .0 5或 P<0 .0 1) ,并能明显减少抗体阳性反应率 ,极显著地减少气囊损伤记分 (P<0 .0 1)     

氟罗沙星对禽败血霉形体（Mycoplasma gallisepticum）病的药效研究

体外抑菌试验测得氟罗沙星（Ｆｌｅｒｏｘａｃｉｎ）对禽败血霉形体（Ｍｙｃｏｐｌａｓｍａｇａｌｉｓｅｐｔｉｃｕｍ）的最小抑菌浓度（ＭＩＣ）为０．０１５ｍｇ／Ｌ。体内药效试验表明,氟罗沙星以２５、５０、１００ｍｇ／Ｌ饮水给药和以５、１０、１５ｍｇ／ｋｇ肌注给药（１次／ｄ）,连续用药５ｄ,对人工气囊接种禽败血霉形体培养液（０．２ｍＬ,约含１０８ｃｆｕ）的雏鸡,保护率均为１００％（３０／３０）,而感染不给药组雏鸡存活率为９３．３％（２８／３０）;相对增重率分别为９０．８％、９１．５％、９２．３％和９１．５％、９１．８％、９２．９％,显著高于感染不给药组（７３．２％）;气囊损伤分分别为２．９３、２．６２、０．９３和１．８、１．１、１．０,而感染不给药组为６．５７,差异显著（Ｐ＜０．０５）;血清玻板凝集试验阳性率分别为２０％（２／１０）、１０％（１／１０）、０（０／１０）和３０％（３／１０）、１０％（１／１０）、１０％（１／１０）,均极显著低于感染不给药组１００％（１０／１０）（Ｐ＜０．０１）。氟罗沙星不同给药途径及不同剂量间药效差异不显著。     

Comparative study of Mycoplasma pulmonis and Mycoplasma gallisepticum infections in turkey sinus.

Infraorbital sinuses of young turkeys were injected with virulent strains of Mycoplasma pulmonis and Mycoplasma gallisepticum to compare the diseases caused by the 2 agents. Mycoplasma pulmonis did not cause visible swelling from large quantities of mucous exudate in the sinuses, such as occurs with M gallisepticum, and it could not be recovered by bacteriologic culture technique after 3 weeks. However, slight exudate did accompany the M pulmonis infection. Similarities between the disease caused by M pulmonis and that caused by M gallisepticum included lymphocytic infiltration in the submucosa, swollen epithelial cells, and loss of cilia from sinus epithelial cell surfaces. This strain of M pulmonis, which is pathogenic for rats, was only mildly pathogenic for turkeys and the infection did not persist for long.     

Interactions between the membranes of turkey cells and Mycoplasma meleagridis

We used Myoplsma meleagridis (MM) to infect the RP-9 cells and the eggshell membranes and scanning electron microscopy (SEM) and confocal microscopy to study the interactions between the organisms and the cell surfaces. The surface of the RP-9 cells contained numerous projections. After 24 hr of infection with MM, those projections were either lost or aggregated to the side; MM-like particles could be seen on the surface of the cells, and surface fluorescence could be detected by confocal microscopy. On the surface of MM-infected shell membranes were necrotic fibrous tissues and cells detected by SEM and an intense surface fluorescence detected by confocal microscopy. These results indicate that MM infection of the cell surface can result in cellular damage.