二氟沙星对实验性感染猪链球菌病及支原体性肺炎的药效学研究

本文报道国内新近研制的畜禽专用氟喹诺酮类抗菌药物－二氟沙星对实验性感染猪链球菌病及支原体性肺炎的药效学研究。以试管两倍稀释法测得二氟沙星对兰氏C群类马链球菌（C55120）和猪肺炎支原体（F16株）的最小抑菌浓度（MIC）分别是1．6级及0．16mg/L。肌注给药对猪链球菌病和支原体性肺炎的实验性治疗结果表明，低、中、高剂量二氟沙星组（2．5、5、10mg/kg)及恩诺沙星组（2．5mg/kg)用药5d（每隔12h给药1次）对猪链球菌病的治愈分别是40％、70％、80％及70％，而链球菌感染对照组的死亡率为70％；低、中、高剂量二氟沙星组及恩诺沙星组（2．5mg/kg)用药5d（每隔12h给药1次）对猪支原体性肺炎的治愈率分别是80％、90％、90％及80％；而支原体感染对照组的自愈率为10％。     

乙基环丙沙星对实验性感染猪链球菌病及水肿病的药效学研究

本文报道以国内新近研制的畜禽专用氟喹诺酮类抗菌药──乙基环丙沙星（Ｅｎｒｏｆ－ｌｏｘａｃｉｎ），进行对实验性感染猪链球菌病及水肿病的药效学研究（２３０头猪）。试管两倍稀释法测得乙基环丙沙星对兰氏Ｃ群类马链球菌（Ｃ＿（５５１２０））和猪大肠杆菌（Ｏ＿（５４））的最小抑菌浓度（ＭＩＣ）分别是０．８及０．０５μｇ／ｍｌ。肌注给药对猪链球菌病和水肿病的实验性治疗结果表明，乙基环丙沙星低、中、高剂量组（分别为１．２５、２．５、１０ｍｇ／ｋｇ）用药６０（每天２次）对猪链球病的治愈率分别是５０％、９５％及９５％，而链球菌感染对照组的死亡率为７０％；乙基环丙沙星低、中、高剂量组（分别为１．２５、２．５、１０ｍｇ／ｋｇ）用药３ｄ（每隔１２ｈ给药一次）对猪水肿病的治愈率分别是８５％、９０％及９０％；而大肠杆菌感染对照组的死亡率为９０％。     

环丙沙星对实验性猪支原体性肺炎的药效学研究

测定环丙沙星及对照药物对猪肺炎支原体的最小抑菌浓度，其中环丙沙星的抗支原体活性最强，最小抑菌浓度为0．01μg/ml。通过给18头健康猪气管内接种含有猪肺炎支原体的病肺悬液，复制具有典型症状的猪支原体性肺炎疾病模型，并进行环丙沙星2．5、5．0mg/kg肌注给药对实验性猪支原体性肺炎的疗效实验及血浆药物浓度监测，两组治愈率分别为83．3％（5／6）和100％（6／6）。治疗组多剂量给药期间，第1、3、5、7、9次给药后0．5及6h的血浆药物浓度，在2．5mg/kg剂量组平均为0．41μg/ml和0．17μg/ml,5.0mg/kg剂量组平均为0．71μg/ml和0．28μg/ml。两剂量组环丙沙星均无蓄积作用。     

乙基环丙沙星对实验性感染猪链球菌病及水肿病的药效学研究

本文报道以国内新近研制的畜禽专用氟喹诺酮类抗菌药－－乙基环丙沙星（Ｅｎｒｏｆ－ｌｏｘａｃｉｎ），进行对实验性感染猪链球菌病及水肿病的药效学研究（２３０头猪）。试管两倍稀释法测得乙基环丙沙星对兰氏Ｃ群类马链球菌（Ｃ５５１２０）和猪大肠杆菌（Ｏ５４）的最小抑菌浓度（ＭＩＣ）分别是０．８及０．０５ｕｇ／ｍｌ。肌注给药对猪链球菌病和水肿病的实验性治疗结果表明，乙基环丙沙星低、中、高剂量组（分别为１．２５、     

单诺沙星对人工诱发鸡大肠肝菌病的药效试验

根据试管 2倍稀释法测定的单诺沙星及氯霉素对鸡大肠杆菌的最小抑菌浓度 ,对实验性大肠杆菌病鸡进行内服给药 (每隔 12h给药 1次 ,连续 3d)治疗试验。结果表明 ,单诺沙星及氯霉素对鸡大肠杆菌的最小抑菌浓度分别是 0 0 5及 1 6mg/L。单诺沙星以 5mg/kg、氯霉素以40mg/kg的剂量给鸡内服后 ,对大肠杆菌病的治愈率分别为 87 5%及 55 0 %。     

麻保沙星对鸡实验性葡萄球菌病的药效学研究

本研究首先测定了麻保沙星对金黄色葡萄球菌的体外抑菌作用，然后对人工感染金黄色葡萄球菌的病鸡进行临床疗效试验。人工发病6小时后，分别以2.5、5、10mg/kg体重的剂量内服和肌注麻保沙星（每组30只鸡），一天1次，连续给药3天。结果表明，麻保沙星对金黄色葡萄球菌的最小抑菌浓度为0.2μg/ml；对鸡实验性葡萄球菌病，麻保沙星（5、10mg/kg)有显著疗效，治愈率为80％－90％。     

阿米卡星脂质体对猪肺疫的疗效试验

为研究阿米卡星脂质体的临床疗效,对10例被诊断为患猪肺疫（猪巴氏杆菌病）的仔猪进行了疗效试验。将患猪随机分为3组,空白对照组肌肉注射生理盐水;药物对照组肌肉注射阿米卡星,剂量为7．5mg／kg,每天用药2次,连用5d;试验药物组肌注阿米卡星脂质体,剂量为5．0mg／kg,每天用药1次,连用3d。结果表明,阿米卡星脂质体组治愈率和有效率分别为70．0％和76．0％,疗效显著高于药物对照组（P〈0．01）。     

沙拉沙星对实验性感染猪链球菌病及大肠杆菌病的药效学

为兽医临床合理应用沙拉星（Ｓarafloxacin）提供理论依据,就其对实验性感染猪链球菌 病及大肠杆菌病的药效学进行了研究。以试管２倍稀释法测得沙拉沙星对兰氏Ｃ群类马链球菌（Ｃ５５１２０）和猪大肠杆菌（Ｏ５５）的最小抑菌浓度（ＭＩＣ）分别是０．８mg/Ｌ及０．０５mg/Ｌ。肌注给药对猪链球菌病和大肠杆菌病的试验性治疗结果不明,低、中 高剂量沙拉沙星组２．５、５、１０mg/kg）及环丙沙星组（５mg/kg）用药５d（每隔１２     

猪水肿抗毒注射液防治水肿病的研究

选用经实验室确诊的患水肿病的仔猪250头,分别用猪水肿抗毒注射液、猪康宁注射液、尖峰抗肿注射液、氧氟沙星注射液肌肉注射治疗;另选怀孕母猪15头,在临产前第7天和第3天用药,观察对仔猪水肿病的预防效果.结果猪水肿抗毒注射液按推荐剂量在母猪临产前第7天和第3天肌注给药2次,对仔猪水肿病的预防保护率达94.12%;发病仔猪肌注给药1次,有效率为96%,治愈率为92%,均优于其它药物,配合尖峰抗肿注射液和猪康宁注射液肌肉注射的有效率达98%以上.试验结果表明,猪水肿抗毒注射液是一种预防和治疗仔猪水肿病的新型专用药物.     

银黄注射液治疗猪肺疫的实验研究

用多杀性巴氏杆菌标准强毒株×73株,人工感染70日龄长白猪致其发病,于接种发病后注射不同剂量的银黄注射液,观察试验猪的临床症状、病理变化、发病率等;试验结果证明:0.1 mL/kg、0.15 mL/kg、0.2 mL/kg 3种不同剂量的银黄注射液,每天注射2次,连续给药5 d,可有效治疗人工感染发病的猪肺疫,其治愈率分别为:低剂量组88.00%;中剂量组96.00%;高剂量组98.00%.中、高剂量银黄注射液的疗效与皮下注射10 mg/kg磷酸替米考星注射液相当,治愈率均在96%以上,推荐银黄注射液治猪肺疫的剂量为每次0.15 mL/kg,每天2次,连续用药5 d.0.2 mL/kg的高剂量组也没出现明显的不良反应,表明这个剂量在临床上也是安全的,对于病程较长的猪可以考虑用高剂量.     

二氟沙星对实验性感染猪支原体性肺炎及链球菌病的药效学研究

以试管两倍稀释法测得二氟沙星对猪肺炎支原体（ Ｆ１６ 株）和兰氏 Ｃ 群类马链球菌（ Ｃ５５ １ ２０ ）的最小抑菌浓度分别是０１６ｍ ｇ／ Ｌ及 １６ｍ ｇ／ Ｌ。肌注给药对猪支原体性肺炎及链球菌病的实验性治疗结果表明,低、中、高剂量二氟沙星组（２５、５、１０ｍ ｇ／ｋｇ）及蒽诺沙星组（２５ｍ ｇ／ｋｇ）用药 ５ 天（每隔 １２ 小时给药一次）对猪支原体性肺炎的治愈率分别是 ８０％ 、９０％ 、１００％ 及９０％ ;而支原体感染对照组的自愈率为１０％ 。低、中、高剂量二氟沙星组及蒽诺沙星组（２５ｍ ｇ／ｋｇ）用药 ４ 天（每隔 １２ 小时给药一次）对猪链球菌病的治愈率分别是 ５０％ 、８０％ 、８０％ 及 ８０％ ,而链球菌感染对照组的死亡率为 ５０％ 。     

Serum pharmacokinetics of clindamycin hydrochloride in normal dogs when administered at two dosage regimens

The aim of this cross-over study was to compare clindamycin pharmacokinetics in the serum of clinically normal dogs when administered orally at two dosage regimens (5.5 mg/kg, twice daily, and 11 mg/kg, once daily), separated by a 1 week wash-out period. Serum samples were obtained from six clinically normal laboratory beagles before, 3, 6, 9 and 12 h after the first and fifth dose of clindamycin at 5.5 mg/kg, twice daily, and before, 3, 6, 9, 12, 18 and 24 h after the first and third dose at 11 mg/kg, once daily. Serum clindamycin concentrations were determined by reverse-phase liquid chromatography coupled with mass spectrometry. Results were analysed using Student's paired t-test, at a 5% level of significance. Values of pharmacokinetic parameters that differed significantly between the two dosage regimens included the following: maximal concentration and area under the concentration-time curve were higher at 11 mg/kg, once daily, than at 5.5 mg/kg, twice daily; and, more importantly, the ratio of AUC(0-24) to the minimal inhibitory concentration (MIC) value of 0.5 μg/mL for a 24 h period (AUC(0-24)/MIC) was higher when clindamycin was administered at 11 than at 5.5 mg/kg, at least during the first day of drug administration. Therefore, a better pharmacokinetic profile may be expected when clindamycin is administered at 11 mg/kg, once daily, for the treatment of canine pyoderma caused by Staphylococcus pseudintermedius.     

Pharmacokinetics of florfenicol in normal and Pasteurella-infected Muscovy ducks

1. Disposition kinetics of florfenicol were studied in Pasteurella-free (control) and Pasturella-infected Muscovy ducks following intravenous and/or intramuscular injection in a single dose of 30 mg/kg body weight. In addition, the tissue distribution and residual pattern of the drug were determined in diseased ducks. 2. The maximum serum concentration of florfenicol in control healthy and infected ducks was reached 1 hour after intramuscular injection but the peak concentration in control ducks was higher than in infected birds. 3. The volume of distribution, total body clearance and systemic bioavailability were higher in infected ducks than in control birds 5.15 l/kg, 10.24 ml/kg/min and 73.03% respectively. Data relating to intravenous injection were analysed using a 2 compartment open model curve fit. 4. Florfenicol was not detected in the serum of infected ducks on the 7th day following intramuscular administration of 30 mg/kg body weight twice daily for 5 successive days but was detected in kidney, bile and liver.     

Posologic evaluation of clindamycin, using a canine model of posttraumatic osteomyelitis

Posttraumatic osteomyelitis attributable to Staphylococcus aureus infection was experimentally induced in 30 dogs, after which the dogs were treated with clindamycin at various dosage regimens. Of the regimens evaluated, oral administration of 11 mg of clindamycin/kg of body weight twice daily for 28 days was the most effective treatment for the osteomyelitis.     

Pharmacokinetics of marbofloxacin in pigs after intravenous and intramuscular administration of a single dose of 8 mg/kg: dose proportionality,influence of the age of the animals and urinary elimination

The pharmacokinetics of marbofloxacin in pigs were evaluated as a function of dose and animal age following intravenous and intramuscular administration of a 16% solution (Forcyl^®). The absolute bioavailability of marbofloxacin as well as the dose proportionality was evaluated in 27‐week‐old fattening pigs. Blood PK and urinary excretion of marbofloxacin were evaluated after a single intramuscular dose of 8 mg/kg in 16‐week‐old male pigs. An additional group of 12‐week‐old weaned piglets was used for the evaluation of age‐related kinetics. The plasma and urine concentration of marbofloxacin was determined using a HPLC method. Pharmacokinetic parameters were calculated using noncompartmental methods. After intravenous administration in 27‐week‐old fattening pigs, the total body clearance was 0.065 L/h·kg. After intramuscular administration to the same animals, the mean observed C_max was 6.30 μg/mL, and the AUC_INF was 115 μg·h/mL. The absolute bioavailability was 91.5%, and dose proportionality was shown within the dose range of 4–16 mg/kg. The renal clearance was about half of the value of the total clearance. The total systemic clearance values significantly decreased as a function of age, being 0.092 L/h·kg and 0.079 L/h·kg in pigs aged 12 and 16 weeks, respectively.     

Evaluation of a single dose versus a divided dose regimen of amoxycillin in treatment of Actinobacillus pleuropneumoniae infection in pigs

The theory of a time-dependent effect of amoxycillin was examined in a model of porcine Actinobacillus pleuropneumoniae (Ap)-infection using clinically relevant dosage regimens. Twenty hours after infection of fourteen pigs, when clinical signs of pneumonia were present, one group of pigs received a single dose of amoxycillin (20 mg/kg, i.m.), whereas another group received four doses of 5 mg/kg injected at 8-h intervals. A similar AUC of the plasma amoxycillin concentration versus time curve was obtained in the two groups, whereas the maximum concentration was threefold higher using the single high dose. Plasma amoxycillin was above the MIC for twice as long using the fractionated dosage scheme. The condition of the animals was evaluated by clinical and haematological observations combined with quantification of biochemical infection markers: C-reactive protein, zinc and ascorbic acid. Within 48 h of treatment, the pigs in both treatment groups recovered clinically. No significant differences in the time-course of clinical observations or plasma concentrations of the biomarkers of infection were observed between the two treatments. In conclusion, the efficacy of these two dosage regimens of amoxycillin was not significantly different in treatment of acute Ap-infection in pigs.     

Long-term efficacy of trilostane administered twice daily in dogs with pituitary-dependent hyperadrenocorticism

Trilostane is considered an efficacious and safe medication for canine pituitary-dependent hyperadrenocorticism (PDH). Its recommended frequency of administration is once daily. In this prospective study, the efficacy, toxicity, and long-term outcome of trilostane administered twice daily per os were evaluated in 44 dogs with PDH. Mean initial dose was 3.1 mg/kg q 12 hours, and mean final dose was 3.2 mg/kg q 12 hours. The final total daily dose was lower than previously reported for once-daily administration. The mean survival time for affected dogs was 930 days.     

Efficacy of ceftiofur hydrochloride for treatment of experimentally induced colibacillosis in neonatal swine

Ceftiofur hydrochloride was tested for effectiveness against induced colibacillosis in neonatal swine. In this model, pigs less than 12 hours old were inoculated via stomach tube with a virulent, K99+, nalidixic acid-resistant strain of Escherichia coli. Six hours after challenge exposure, 1 dose of ceftiofur was administered either IM or orally in experiment 1 and orally only in experiment 2. Mortality, shedding of bacteria, fecal consistency scores, and body weight changes were monitored for 10 days. In experiment 1 (n = 383 pigs), all treatments at dosage that ranged between 0.5 and 64.0 mg of ceftiofur/kg of body weight significantly (P less than 0.001) reduced mortality, bacterial shedding, and diarrhea and increased weight gain, compared with findings in untreated controls. There were no detectable differences between oral and IM routes, except that there was greater reduction in bacteria shedding associated with the oral route of administration. In experiment 2 (n = 505 pigs), ceftiofur was administered orally either once at 6 hours after challenge exposure or twice at 6 and at 48 hours after the first dose. Dosage of ceftiofur was 0, 5, 10, 20, 30, or 60 mg/kg administered once, or half the same dose was administered at each of 2 times. At the optimal dosage (10 mg/kg), a single dose was as effective as 2 doses. The single administration at all dosages reduced mortality, bacterial shedding, and diarrhea scores and increased body weight gain, compared with findings in untreated pigs (P less than 0.01). In this induced infection model, the optimal treatment dosage was determined to be 10 mg/kg administered once.