HPLC法测定氨苄西林钠可溶性粉中氨苄西林的含量

采用HPLC法测定氨苄西林钠可溶性粉中氨苄西林的含量.色谱柱为WaterssphericalC18(3.9mm×150mm,5μm),流动相为水-乙腈-1mol/L磷酸二氢钾溶液-1mol/L醋酸溶液(909∶80∶10∶1,V/V),检测波长254nm,流速1.0mL/min,柱温30℃,保留时间约4.5min.氨苄西林在0.25～2.0mg/mL范围内具有良好的线性关系(r=0.9999),平均回收率99.6%,RSD为0.3%.     

高效液相色谱法测定蜂王幼虫中的几丁多糖含量

采用高效液相色谱-示差折光检测器方法对蜂王幼虫中的几丁多糖含量进行测定.色谱条件:YMC-Pack NH2柱(250×4.6mm,5μm),流动相为乙腈-纯水(体积比为50∶50,用乙酸调pH至4.0),流速为1.0 mL/min,柱温30℃,进样量为20μL.本方法在10～1000μg/mL线性范围内的线性相关系数为0.9996,日内和日间相对标准偏差小于10%,回收率在70%～103%之间.该方法简便、快速、稳定,可用于蜂王幼虫中几丁多糖含量的测定.     

RP-HPLC法测定阿莫西林-盐酸环丙沙星可溶性粉的含量

应用RP-HPLC法测定阿莫西林-盐酸环丙沙星可溶性粉的含量.采用Shim-pack CLC-ODS C18柱(150 mm×6 mm, 5 μm),以1.5×10-2 mol/L三乙胺溶液(用磷酸调pH至3.0)-乙腈 (体积比85∶ 15)为流动相,流速为1.0 mL/min,检测波长为229 nm,柱温为40 ℃.在此色谱条件下两者能完全分离,阿莫西林、盐酸环丙沙星分别在22～108 μg/mL和29～146 μg/mL范围内峰面积与浓度呈良好的线性关系,相关系数均为0.999 9.阿莫西林、盐酸环丙沙星的回收率分别为99.50%～100.20%和99.30%～99.86%(n=5);RSD分别为0.60%～1.00%和0.86%～1.02%(n=5).本法可用于阿莫西林-盐酸环丙沙星可溶性粉的质量控制.     

HPLC法测定鸡蛋中土霉素和金霉素的残留量

采用RP-HPLC方法同时测定了鸡蛋中土霉素和金霉素的残留量.用0.01 mol/L的乙二胺四乙酸二钠溶液和0.3%磷酸溶液为提取液,三氯乙酸(1 1)溶液为蛋白沉淀剂,离心后上清液经C18固相萃取柱净化、浓缩.色谱柱为Waters Symmetry ShieldTM RP18柱,250 mm×4.6 mm (i.d.),粒径5 μm;检测波长353 nm;以0.02 mol/L草酸∶乙腈∶ 0.01 mol/L磷酸二氢钠(45∶ 19∶ 36,V/V/V)为流动相.土霉素和金霉素标准曲线的线性范围分别为0.05～1.0 μg/mL和0.1～2.0 μg/mL.经过3种不同浓度回收率的测定,其回收率在50.6%～85.6%之间,RSD%小于8.60%(n＝5).     

离子对高效液相色谱法测定复方甲硝唑片中甲硝唑和维生素B6含量

建立了同时测定复方甲硝唑片中甲硝唑和维生素B6含量的离子对HPLC方法.采用ODS色谱柱,流动相为磷酸二氢钾和庚烷磺酸钠水溶液(每1L中含磷酸二氢钾13.6 g与庚烷磺酸钠1.0 g)-甲醇-三乙胺(85∶15∶0.4),用磷酸调pH至2.8;检测波长290 nm,以峰面积计算,外标法定量.甲硝唑和维生素B6的线性范围分别为100～300 μg/mL(r=0.999 9)和5～50 μg/mL(r=0.999 9);平均回收率分别为100.2%(RSD=1.0%,n=6),99.8%(RSD=1.2%,n=6).该方法测定结果准确,操作简便,回收率高.     

牛羊肉中氯氰碘柳胺残留检测ＨＰＬＣ法的研究

对牛、羊肉中氯氰碘柳胺(Closantel)残留的检测方法进行了研究.取2 g动物组织样品用乙腈提取,正己烷脱脂,于50℃减压蒸干.残留物用2 mL甲醇-正己烷(8∶ 2)溶解,通过氧化铝B柱,用2 mL正己烷淋洗,不收集;该柱用10 mL甲醇洗脱,收集洗脱液于50℃减压蒸干后,残留物用1.0 mL的流动相溶解并用带有紫外检测器的高效液相色谱仪于221 nm波长处测定;流动相为乙腈∶水(85∶ 15),含有0.05%二乙胺并用磷酸调整pH值至3.氯氰碘柳胺浓度在200～8 000 ng/mL时,呈线性关系,检测限量为25 μg/kg.本方法平均回收率为87.8%±7.5%(牛肉)、83.2%±10.0%(羊肉).     

高效液相色谱法检测鸡粪便中洛克沙胂

建立了用固相萃取-高效液相色谱法(HPLC)测定鸡粪便中洛克沙胂(ROX)的方法。鸡粪便采用0.05 mol/L磷酸氢二钾∶甲醇=90∶10(V/V)溶液作提取液,用Waters Oasis(MAX固相萃取小柱净化;色谱条件为:Agilent C18色谱柱(4.6×250 mm,5μm),流动相为0.05 mol/L磷酸二氢钾∶100 mL/L乙酸∶甲醇=90∶7∶3(V/V/V),流速1.0 mL/min,柱温30℃,进样量20μL,紫外检测波长266 nm。ROX的浓度在10.0μg/mL范围内,线性相关系数为0.999 9,方法的回收率为80.09%～81.5%,变异系数为2.09%～5.87%,检出限为1.0 mg/kg。该方法精确度和灵敏度很高,适用于鸡粪便中ROX含量的测定。从某鸡场随机采集8个粪样,调查鸡粪中的ROX含量,其ROX的平均浓度为21.49 mg/kg。     

小柴胡散中黄芩苷含量测定HPLC法研究

建立了测定小柴胡散中黄芩苷含量的高效液相色谱法.采用Hypersil BDS C18柱(5 μm,4.6 mm×200 mm),以甲醇-0.025%磷酸溶液(55∶ 45,V/V)为流动相,紫外检测器检测波长为280 nm.对照品在0.038 6～0.617 0 μg/mL的浓度范围内呈现良好的线性关系(R2=0.998 5),黄芩苷加样平均回收率为 98.61%,RSD为 2.64%.该方法简便、准确、快速,适合于小柴胡散的质量控制检测.     

高效液相色谱法测定土霉素片的含量

采用高效液相色谱法测定土霉素片的含量。色谱条件:采用KromasilC18(200mm×4.6mm,5μm)色谱柱;流动相为0.05mol/L草酸铵溶液-二甲基甲酰胺-0.2mol/L磷酸氢二铵溶液(75∶20∶5),用氨试液调pH值至8.0±0.2;流速0.8mL/min,柱温35℃;检测波长280nm。该方法的线性范围为50～200μg/mL,线性方程:A=1748.3X+42142r=0.9999。平均回收率为100.02%,RSD=0.1%。本法具有专属性,能有效地测定土霉素片的含量。     

HPLC法测定黄芩苷-β-环糊精包合物中黄芩苷的含量

建立了用HPLC测定黄芩苷-β-环糊精包合物中黄芩苷含量的方法.色谱柱为CLC-ODS C18柱,以甲醇-水-磷酸(47∶ 53∶ 0.2)为流动相,检测波长280 nm,外标法定量.检测的线性范围为20.0～80.0 μg/mL,回归方程为y=9 753.1 x 1 546, r=0.999 3(n=5),平均加样回收率为99.37%(n=5),RSD为0.67%(n=6).本方法准确、可靠、重现性好,可作为黄芩苷-β-环糊精包合物中黄芩苷的含量测定方法.     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

A brief history of the prevention of infectious diseases by immunisations

Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.