苄星氯唑西林原料药的无菌检查方法研究

采用自然沉降-薄膜过滤-酶中和相结合的方法,按照《中国兽药典》2010年版一部附录进行试验,旨在建立苄星氯唑西林原料药的无菌检查法并进行验证。结果:以1.0%聚山梨酯80 p H 7.0氯化钠-蛋白胨缓冲液冲洗,冲洗量400 m L/膜,在最后的培养基中加入不少于600万U的青霉素酶可有效消除样品对各试验菌株的抗菌活性;验证试验中,各验证菌生长良好,各供试品管均未见菌生长,表明该方法可靠、准确,可用于苄星氯唑西林的无菌检查。     

苄星头孢匹林乳房注入剂无菌检查方法的研究

本文建立了苄星头孢匹林乳房注入剂的无菌检查方法。采用酶中和-直接接种法联用的无菌检查法,根据《中国兽药典》2015年版一部附录要求进行试验。分别进行了培养基的灵敏度和无菌检查、方法适用性试验。结果表明:培养基的灵敏度和无菌检查均符合要求,青霉素酶加入量为至少1.2×10~8 U(每1 mL供试品加入不少于200万U),可有效消除样品的抗菌活性对检查带来的干扰,此方法可靠、准确,可作为苄星头孢匹林乳房注入剂的无菌检查方法。     

利福昔明乳房注入剂对干奶期奶牛临床型乳房炎预防效果观察

本试验旨在观察利福昔明乳房注入剂对干奶期奶牛临床性乳房炎的预防效果.选择非临床型乳房炎的泌乳末期健康奶牛共计75头,随机分为空白对照组(不给药对照组),苄星氯唑西林乳房注入剂对照组(600 mg/乳区),利福昔明高(400 mg/乳区)、中(200 mg/乳区)、低(100 mg/乳区)三个剂量组,每组15头.分别在干乳期、泌乳期进行乳房观察,并采用致病菌的分离培养和乳汁中体细胞计数检测临床型乳房炎发生情况.结果表明,利福昔明低剂量组保护率与空白对照组保护率相比差异显著(P＜0.05),苄星氯唑西林对照组、利福昔明中剂量组、高剂量组对干奶期奶牛临床型乳房炎的预防效果与空白对照组相比,差异极显著(P＜0.01);利福昔明高、中剂量组与苄星氯唑西林对照组之间的预防效果差异不显著(P＞0.05).结果提示,利福昔明乳房注入剂对临床型奶牛乳房炎有较好的预防效果,可以作为预防类药物用于奶牛生产中,降低奶牛乳房炎的发生率.     

头孢洛宁乳房注入剂(干乳期)对干乳期奶牛乳房炎的预防和疗效观察

为在研究头孢洛宁乳房注入剂(干乳期)治疗和预防奶牛干乳期乳房炎的临床疗效,本试验选择60头临近干乳期的奶牛,随机分配到头孢洛宁乳房注入剂(干乳期)高(2支/乳室)、中(1支/乳室)、低(0.5支/乳室)剂量组和苄星氯唑西林乳房注入剂组(对照组,1支/乳室)。结果显示,按照临床推荐剂量1支/乳室的剂量乳房注入头孢洛宁乳房注入剂(干乳期),能够有效治疗奶牛干乳期因敏感菌引起的乳房炎,并预防乳房内新增感染。     

加米霉素注射液无菌检查方法的试验

本文建立了加米霉素注射液的无菌检查方法。采用薄膜过滤法,根据《中国兽药典》2015年版一部附录要求进行试验,以0.1%无菌蛋白胨的0.1%聚山梨酯80溶液冲洗,冲洗量为500 mL/膜,验证试验结果显示,各验证菌生长良好,各供试品管均未见细菌生长。本试验成功建立了可靠、准确、可用于加米霉素注射液的无菌检查法。     

苄星氯唑西林国家对照品的研制

为了研制首批苄星氯唑西林国家对照品。对质量标准中的关键项目进行考察。采用红外分光光度法、高效液相色谱法对原料进行鉴别,采用高效液相色谱法进行含量测定。结果显示,红外光吸收图谱与USP溯源对照品图谱一致,高效液相色谱法测定氯唑西林与二苄基乙二胺的含量和为92.1%。研究建立的苄星氯唑西林国家对照品可用于苄星氯唑西林及其制剂的鉴别。     

盐酸头孢噻呋乳房注入剂无菌检查方法的建立

为建立盐酸头孢噻呋乳房注入剂的无菌检查方法,本试验按照《中华人民共和国兽药典》2015年版一部附录1101无菌检查法中方法适用性试验的有关要求,对取样量、稀释液种类、冲洗方式、加酶量等进行了考察。取供试品置于无菌分液漏斗中,加300 mL无菌十四烷酸异丙酯,摇匀,再加200 mL含1%聚山梨酯80的0.1%无菌蛋白胨溶液,充分振摇,静置,取水层,按照薄膜过滤法处理,用pH 7.0无菌氯化钠－蛋白胨缓冲液为冲洗液,每张滤膜每次冲洗量为100 mL,冲洗4次,每管培养基中加入600万单位的青霉素酶溶液。结果显示,方法适用性试验中,供试品6种阳性菌试验组与阳性菌对照组相比均生长良好,供试品组、阴性对照组均无菌生长,说明供试品的检验量在该检验条件下已消除其抑菌作用。盐酸头孢噻呋具有较强的抑菌活性,本试验采用薄膜过滤法,建立了合理的无菌检查方法,能有效去除盐酸头孢噻呋乳房注入剂中的抑菌成分,使检验结果更准确、可靠,可作为该制剂的常规无菌检查方法。     

苄星氯唑西林乳房注入剂的效果评价

正苄星氯唑西林是一种半合成的抗生素,属于β-内酰胺类,具有耐酸、耐酶的特点,尤其对耐青霉素金黄色葡萄球菌有效[1]。本试验选用的试验药品采用先进的球磨技术,将药物制备成均一、细小的颗粒,有助于增加药物的分子表面积,提高了药物在乳区中的浓度;将苄星氯唑西林与长效疏水性基质相结合,可起到缓慢释放药物的作用,最终有效浓度可维持45 d。     

农业部发布进口兽药注册目录公告

农业部于2001年12月29日发布第183号公告，发布进口兽药注册目录。全文如下：中华人民共和国农业部公告第183号根据《进口兽药管理办法》的规定，经审核，批准美国法玛西亚公司等12家公司的23种兽药产品在我国注册或再注册，并核发《进口兽药登记许可证》(品种见进口兽药注册目录)，注册目录中的硫酸庆大霉素注射液和盐酸氨丙啉执行《中国兽药典》标准，氨苄西林钠、氯唑西林钠乳房注入剂(泌乳期)和氨苄西林钠、苄星氯唑西林乳房注入剂(干乳期)执行随本公告发布的质量标准，原我部发布的同品种进口兽药质量标准同时废止，其余产品执行农业部…     

维生素ADE注射液的无菌检查方法研究

依据《中国兽药典(一部)》2015年版"无菌检查法",通过培养基灵敏度检查、方法适用性试验和无菌检查等方法,对新兽药维生素ADE注射液进行了无菌检查方法研究。结果显示:采用薄膜过滤法,先用无菌IPM 100 mL冲洗,再用含0.1%吐温-80的0.1%蛋白胨灭菌溶液冲洗2次(每次100 mL),可消除样品中苯甲醇对各试验菌株的影响。无菌检查结果显示:样品和阴性对照未见菌生长,阳性对照菌生长良好。该方法可用于维生素ADE注射液的无菌检查,能够保证结果准确可靠。     

高效液相色谱法测定苄星邻氯青霉素乳房注入剂中苄星邻氯青霉素的含量

用反相高效液相色谱法测定苄星邻氯青霉素乳房注入剂中苄星邻氯青霉素的含量。采用AgilentEclipseXDB-C185μm4.6×150mm色谱柱;流动相为0.1mol/L磷酸二氢钠-乙腈(3:1);检测波长为220nm;柱温为40℃。在该色谱条件下,苄星邻氯青霉素在20μg/ml～180μg/ml浓度范围内线性关系良好,相关系数r=0.99999;100%浓度时平均回收率为100.7%,RSD=0.04%。该方法快速灵敏,准确实用。     

复方阿莫西林乳房注入剂无菌检查方法的确立

建立了复方阿莫西林乳房注入剂的无菌检查方法。根据《中国兽药典》2010年版一部附录要求,通过比较薄膜过滤法和直接加入法对本品的适用性,最终选用直接加入法作为无菌检查方法,即以每1 mg阿莫西林中加入9000单位的青霉素酶来消除供试品的抑菌活性,并通过无菌方法验证,证明该方法适用于对复方阿莫西林乳房注入剂进行无菌检查。     

A note on effectiveness of dry cow therapy in New Zealand dairy herds

Two dry-cow therapy products were evaluated in seven factory-supply dairy herds in the Waikato area. A product containing neomycin sulphate and the benzathine salt of penicillin (Neopen D.C. White; Smith-Biolab) was used in five herds, and one containing benzathine cloxacillin (Orbenin, Beecham) was used in two herds. Non-treated control cows were included in each herd. Both products were effective in eliminating intramammary infections with Staphylococcus aureus, Streptococcus uberis, and Streptococcus agalactiae. Efficacy of dry-cow therapy against S. aureus was 83.8% and 85.2% respectively. Spontaneous cure rate among controls was 30.8% for S. aureus during the dry period. Spontaneous cure rate for Str. uberis was 50%, while dry-cow therapy eliminated 100% and 77.8%, respectively, for the two products. Dry-cow therapy with either product eliminated more than 90% of Str. agalactiae infections while spontaneous cure rate was only 28.6%. These results further support the effectiveness of dry-cow therapy in reducing the level of subclinical mastitis in dairy herds by shortening the duration of intramammary infections.     

Influence of the genotype of Staphylococcus aureus, determined by pulsed-field gel electrophoresis, on dry-period elimination of subclinical mastitis in Canadian dairy herds

By combining information from 2 databases, we investigated the possibility of an association between the genotype of Staphylococcus aureus causing bovine intramammary infection and dry-period cure of subclinical infection. The 1st database contained bacteriologic and cow data from a field study evaluating the efficacy in such infections of a new intramammary dry-cow therapy (DCT) containing tilmicosin phosphate, in comparison with a commercially available DCT containing benzathine cloxacillin. Isolates of S. aureus from that study were frozen and later independently analyzed by pulsed-field gel electrophoresis (PFGE) and macrorestriction DNA fingerprinting. The molecular information, summarized and published elsewhere, constituted the 2nd database. Data from 121 subclinically infected quarters of 92 cows from 40 herds were studied by univariate and multivariable regression analysis. Infection by an isolate of PFGE lineage group D was more likely than infection by an isolate of group A or F to be cured (P < 0.05). Cows infected by lineage group D had a higher linear somatic cell count score (LS) from the last Dairy Herd Improvement test before the dry period than did cows infected by the other lineage groups (P = 0.04). Although the probability of cure was significantly lower for cows with an LS at or above the mean of 5.7 for the study population (P = 0.05), when such a cow was infected with lineage group D, cure was significantly more likely (P < 0.001) than when it was infected by another lineage group. Significantly more (P = 0.02) of the infections treated with tilmicosin (74%) than of those treated with benzathine cloxacillin (53%) were cured, and significantly more (P = 0.05) of the infections by group D (81%) than of those by group A (57%) or group F (54%) were cured. However, there was no difference in cure rate for any PFGE genotype when tilmicosin phosphate was administered; when benzathine cloxacillin was administered, 87% of lineage group D isolates were eliminated, as compared with 46% of group A and 33% of group F isolates (P < 0.05). This research demonstrates that certain genotypes of S. aureus may naturally elicit a greater inflammatory response, yet be more susceptible to elimination by antibiotics in the dry period, than other genotypes.     

Assessment of antimicrobial transfer from treated to untreated mammary gland quarters by use of high-pressure liquid chromatography for detection of cloxacillin in milk samples from nonlactating dairy cows

OBJECTIVE: To determine whether half-udder intramammary infusion of cloxacillin results in transfer of cloxacillin from treated to untreated mammary gland quarters within nonlactating cows, and, if so, at what concentrations, and to determine whether selection of ipsilateral versus diagonal-contralateral quarters for treatment affects cloxacillin transfer among quarters. ANIMALS: 20 Holstein-Friesian cows from a dairy herd. PROCEDURES: A within-cow half-udder comparison trial was used in which 2 of 4 mammary gland quarters (ipsilaterally or diagonally) received an intramammary infusion of cloxacillin on day 1 of the nonlactating period. Three days later, milk samples were taken from all untreated quarters and high-pressure liquid chromatography was used to detect and quantify milk cloxacillin concentrations. RESULTS: Cloxacillin was detected in 25% of all untreated mammary gland quarters. Mean cloxacillin concentration in untreated quarters was below minimum inhibitory concentrations for targeted mastitis pathogens. No significant difference in cloxacillin concentrations was found in the ipsilateral or diagonal treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE: Within-cow half-udder comparison trials are valid for antimicrobial trials in nonlactating cows, although transfer of antimicrobials does occur in trace concentrations. Ipsilateral or diagonal-contralateral treatment designs perform similarly. This type of design is economical for researchers, although care must be taken to account for within-cow clustering of mammary gland quarter data.     

Persistence of antibiotics in bovine mammary secretions following intramammary infusion at cessation of milking

A study was conducted to determine the persistence of antibiotic preparations for use in nonlactating cows in bovine mammary secretions following intramammary infusion at cessation of milking. Five commercially available antibiotic formulations were evaluated using 311 cows. All quarters of each cow were sampled once only during the nonlactating period and most cows were sampled at or near parturition. Antibiotic residues were detected qualitatively by the Bacillus stearothermophilus disc assay. Great variation between different antibiotics in persistence in mammary secretion was observed. In general, mammary secretions from most mammary glands infused with cloxacillin or penicillin-dihydrostreptomycin were positive at 28–35 days after infusion and some were positive at 42–49 days after infusion. On the other hand, <13% of mammary secretions at 7 days after infusion of novobiocin and 50% of mammary secretions at 14 days after infusion of penicillin-novobiocin were positive for antibiotics. Cephapirin benzathine persisted for about 21 days after infusion. Some samples that were positive for antibiotics after initial testing were negative following heating of samples, suggesting that component(s) of dry secretion can inhibit growth of B. stearothermophilus and influence the interpretation of results. Colostrum samples from all quarters except one were negative for antibiotics. These data suggest that nonlactating-cow antibiotic formulations persist primarily during the early to mid-nonlactating period. Based upon present methods of formulation, it would appear that antibiotic preparations for use in nonlactating cows most likely provide little protection during the periparturient period, at a time when mammary glands are highly susceptible to new intramammary infections.     

Cheyletiella parasitivorax infestation of cats associated with skin lesions of man

Two dry-cow therapy products were evaluated in seven factory-supply dairy herds in the Waikato area. A product containing neomycin sulphate and the benzathine salt of penicillin (Neopen D.C. White; Smith-Biolab) was used in five herds, and one containing benzathine cloxacillin (Orbenin, Beecham) was used in two herds. Non-treated control cows were included in each herd. Both products were effective in eliminating intramammary infections with Staphylococcus aureus, Streptococcus uberis, and Streptococcus agalactiae. Efficacy of dry-cow therapy against S. aureus was 83.8% and 85.2% respectively. Spontaneous cure rate among controls was 30.8% for S. aureus during the dry period. Spontaneous cure rate for Str. uberis was 50%, while dry-cow therapy eliminated 100% and 77.8%, respectively, for the two products. Dry-cow therapy with either product eliminated more than 90% of Str. agalactiae infections while spontaneous cure rate was only 28.6%. These results further support the effectiveness of dry-cow therapy in reducing the level of subclinical mastitis in dairy herds by shortening the duration of intramammary infections.     

Antibiotic residues in goats milk following intramammary treatment

Two lactational intramammary antibiotic preparations (cloxacillin and oxytetracycline) were each used to treat eight goatsby intramammary infusion in one half. The rate of release of the antibiotics was monitored by a diffusion assay based on the sensitive organism Bacillus stearothermophilus var. calidolactis. Cloxacillin was still detectable 156 hours afterthe final treatment while oxytetracycline was undetectable 108 hours following treatment. A small but significant amount of antibiotic was translocated between treated and untreated halves of the udder in both cases.