碘醚柳胺脂质体定向剂在绵羊体内的药代动力学及组织残留量

应用碘醚柳胺脂质体定向剂 (包封率 58%)给绵羊单剂量皮下注射 ( 0 .3m g/ kg) ,用反相高效液相色谱法 ( RP- HPLC)测定了该药在绵羊体内不同时间的血浆药物浓度以及组织中的药物残留量。利用 3p87实用药代动力学软件分析 ,结果表明 ,该药的药代动力学符合一室模型 ,动力学方程为 :C =3.116 4( e- 0 .0 192 t- e- 1.5 15 5 t)。药代动力学参数为 :达峰时间 ( Tmax)为 ( 2 .8112± 0 .74 92 ) d,峰浓度 ( Cmax)为 ( 2 .874 2±0 .8716 ) mg/ L,生物半衰期 ( t1/2β)为 ( 36 .386 1± 3.0 385) d,曲线下面积 ( AU C)为 ( 14 3.5530± 4 7.2 354 )μg·m L- 1· d- 1。与皮下注射碘醚柳胺注射液 ( 3mg/ kg)相比 ,达峰浓度时间提前了 1.4 6 47d,半衰期延长了 16 .2 0 97d。碘醚柳胺在绵羊组织中的残留量 ,2 8d时肝脏中为 ( 2 3.0 331± 3.2 0 4 8) μg/ g。肾脏、肌肉和胆汁中一直检测不到药物。与皮下注射碘醚柳胺注射液相比 ,肝脏等富含巨噬细胞的脏器中药物含量明显增高 ,肾脏、肌肉中药物含量相对较低。本试验结果表明 ,碘醚柳胺脂质体定向剂优于碘醚柳胺注射液。     

丙硫咪唑在鸡体内的药代动力学及组织残留的研究

给鸡单剂量口服丙硫咪唑(15mg/kg),用HPLC法测定不同时间的鸡体内药物及其代谢物的浓度.结果,在血浆和组织中均未发现丙硫咪唑,而其两个代谢物丙硫咪唑亚砜(亚砜)和丙硫咪唑砜(砜)在血浆中的药代动力学行为符合方程:C(亚砜)=22.3581(e~(-0.142(t-0.6053))-e~(-0.4505(t-0.8053)));C(砜)=4951.7774(e~(-0.2769(t-0.9111))-e~(0.278(t-0.9111)))。亚砜和砜的主要药动学参数分别为:消除相半衰期(t1/2ke)为4.87和2.57h,表观分布容积(Vd)为0.98和0.76L/kg,峰时间(Tm)为4.34和4.52h,峰浓度(Cm)为8.98和7.22μg/mL。亚砜在心、肝、胰、肺、肾等组织中的残留量:给药后3d分别为1.14、5.35、2.42、1.78、2.45μg/g;5d分别为0.281.79、2.34、1.13、1.16μg/g;7d分别为0.12、0.68、1.69、0.48、0.69μg/g.砜在上述组织中的残留量:给药后3d分别为3.15、10.44、8.16、0.99、2.83μg/g;5d分别为1.53、1.04、4.11、0.86、0 89μg/g;7d分别为:0.77、0.67、2.09、0.53、0.12μg/g。     

高效液相色谱法测定牛羊组织中碘醚柳胺残留量

建立高效液相色谱荧光检测法测定牛羊组织中碘醚柳胺残留量。牛羊组织中残留的碘醚柳胺,经乙腈-丙酮溶液提取,阴离子交换固相萃取柱净化,高效液相色谱-荧光法测定,外标法定量。碘醚柳胺在10～5000 ng/mL的浓度范围内呈现良好的线性关系,碘醚柳胺在牛羊肌肉、肝脏、肾脏、脂肪中的检测限均为2.5 μg/kg,定量限均为5 μg/kg,牛羊肌肉、肝脏、肾脏、脂肪中15～500 ng/g添加浓度范围内的回收率为77.4%～93.8%,批内批间RSD值均<15％。     

国产咪唑苯脲二丙酸盐在牛体内的药代动力学及组织残留

给牛单剂量肌注咪唑苯脲二丙酸盐(2mg/kg)。用紫外分光光度计测出不同时间的血药浓度,并按有吸收一室模型=M(e~(-ket)—e~(-kat))公式,计算出咪唑苯脲的主要药代动力学参数:吸收速率常数(k_a)为2.027h~(-1);清除速率常数(k_e)为0.419h~(-1),峰时间(T~(max))为1.18h;峰浓度(C~(max))为1.746μg/ml;吸收相半衰期(t1/2k_a)为0.342h,消除相半衰期(t1/2k_e)为1.165h;表观分布容积(Vd)为0.88L/kg;体清除率(BIC)为0.25L/kg/h。咪唑苯脲在牛的肝、肾、心,胆汁、脑、肌肉、脂肪中的残留量:停药后1个月分别为0.94、1.47、1.10、1.89,0.81、1.47和0.72μg/g;停药后2个月分别为0.763、0.454、0.232、0.493、0.106、0.662和0.441μg/g;停药后3个月分别为0.512、0.326、0.174、0.019、0.067、0.183和0.058μg/g。     

左旋咪唑擦剂的药代动力学——离子对HPLC法研究

给家兔背部皮肤涂擦左旋咪唑擦剂后,用离子对HPLC法测定了血浆左旋咪唑的含量.以μ-Bondapak C_(12)为固定相,以水-甲醇-庚烷磺酸(v/v为55/45/2)的0.2%乙酸液(pH3.5)为流动相,在波长291nm处检测.最低检测浓度为0.02μg/mL,平均回收率为71.25±3.79%(n=5).左旋咪唑经皮吸收后,其药动学符合—室模型,动力学方程为:(?)=1.75(e~(- 0.0025t)—e~(-0.5129t);其吸收达峰时间(T_(max))为4.03h;峰浓度(C_(max))为0.99μg/mL;消除半衰期(T_((1/2)β))7.49;曲线下面积(A_(mu))为15.57(μg·h)/mL.同时与肌注左旋咪唑的药动学进行了比较.     

碘醚柳胺驱虫对6月龄伊犁马营养物质消化代谢及生长发育的影响

本试验旨在研究碘醚柳胺驱虫对6月龄伊犁马驹营养物质消化代谢及生长发育的影响。试验选取在同一草场饲养的6月龄(出生日期±5 d)、平均体重为(117.60±15.84)kg的伊犁马公马马驹10匹,在相同的饲喂条件下随机分为2组,分别为对照组和试验组,每组5匹。试验组马驹灌服碘醚柳胺混悬液驱虫剂驱虫,每匹14 m L,对照组马驹不进行驱虫。驱虫后,进行为期20 d的消化代谢试验,其中预试期15 d,正试期5 d。结果显示:碘醚柳胺驱虫对马驹各营养物质摄入量、消化量、排出量和消化率均没有产生显著影响(P0.05),但试验组中性洗涤纤维、酸性洗涤纤维、钙消化率分别比对照组高18.17%、16.37%、17.36%;试验组马驹氮的沉积量和沉积率分别比对照组高65.90%(P0.05)和73.20%(P0.05);试验组马驹体高和胸围的总增长分别比对照组高123.58%(P0.05)和48.31%(P0.05)。因此,碘醚柳胺驱虫对6月龄伊犁马营养物质消化代谢的积极作用主要体现在氮沉积量和沉积率的增加以及体高和胸围的增长上。     

碘醚柳胺的研制及其对肝片吸虫的驱虫试验

以３，４－二氯硝基苯为起始原料，经醚化、还原、卤化、缩合等四步反应合成抗肝片吸虫新药碘醚柳胺，用红外光谱、质谱和元素分析等对化学结构进行了确证。建立高效液相色谱法测定绵羊血药浓度及组织残留量。色谱条件：ＯＤＳ柱，流动相为甲醇，检测波长２８３ｎｍ，吸收度与浓度的线性关系范围０～５０μｇ／ｍｌ。碘醚柳胺小鼠骨髓微核试验结果为阴性。驱虫试验表明牛羊按７．５ｍｇ／ｋｇ口服或３ｍｇ／ｋｇ皮下注射对牛羊肝片吸虫的驱虫率和虫卵减少率均达１００％，无任何毒副作用。     

新疆地区绵羊和肉鸡不同组织兽药残留及消除规律研究

为了解新疆地区绵羊生产中使用药物的残留情况,进行了绵羊不同组织兽药残留量的研究。结果表明:停药5d青霉素钠在绵羊肾脏中的残留量最高,是肝脏的4倍,肌肉组织中的残留量最低;停药5d头孢噻呋钠在绵羊各组织内残留量均极低;停药10、20和30d检测结果显示:硫酸链霉素在绵羊的肝脏和肾脏中代谢时间长,残留量高,肌肉组织中代谢快,残留量低;停药17d伊维菌素在绵羊肾脏残留量最高,肝脏和背最长肌均未检出;停药7d阿苯达唑未检出;停药6d左旋咪唑未检出;吡喹酮在停药17、27和37d各检测一批,均未检出。肉鸡42d(出栏)时,新霉素在胸肌和腿肌中残留量最高,肝脏和肾脏中的残留量仅为肌肉组织的四分之一;肉鸡42d(出栏)时,强力霉素在肾脏中的残留量最高,是肌肉组织、心脏和肝脏残留量的10倍左右。证明试验中各种药物的残留量均低于中国和欧共体(EEC)规定的标准残留限量。     

秃疮花针剂在山羊体内的药物动力学研究

研究秃疮花在山羊体内的药物动力学。结果表明,山羊肌注秃疮花针剂后,秃疮花提取物在山羊体内的药动学配置均符合有吸收因素二室开放模型特征,其最佳药-时曲线方程分别为:C=7.344 3e~(-0.148 8t)+1.803 3 e~(-0.058 3t)-9.147 6 e~(-1.628 3t)。主要药物动力学参数:制剂吸收半衰期t_(1/2ka)为(0.425 8±0.006 5)h,分布相半衰期t_(1/2α)为(4.680 6±0.358 2)h,消除半衰期t_(1/2β)为(12.684 8±3.685 0)h,药-时曲线下面积AUC为(73.307 0±0.732 9)μg/(mL·h)峰质量浓度为(6.753 8±0.060 8)μg/mL,达峰时间为(1.690 0±0.015 5)h。提示秃疮花提取物在山羊体内分布较广,吸收快,消除较慢,血药浓度维持时间较长。     

磺胺对甲氧嘧啶和二甲氧苄啶在肉鸡体内的残留消除

采用高效液相色谱-串联质谱法研究磺胺对甲氧嘧啶(SMD)和二甲氧苄啶(DVD)预混剂在白羽肉鸡体内各组织中的残留消除规律。对48只健康白羽肉鸡连续饲喂添加1 000mg/kg磺胺对甲氧嘧啶和二甲氧苄啶预混剂(含SMD 200mg,DVD 40mg)的全价饲料10d,在停药后4h,1、3、6、9、12、15d分别宰杀6只鸡,采集各组织进行药物残留测定。通过空白样品添加回收试验,所有基质中SMD和DVD的定量限分别为10μg/kg和5μg/kg,SMD和DVD分别在50、100、200μg/kg和25、50、100μg/kg 3个添加水平下的平均回收率为71.7%~102.3%,相对标准偏差为1.0%~11.9%。结果表明,磺胺对甲氧嘧啶和二甲氧苄啶预混剂在肾脏中残留量最高,肝脏其次;肌肉和皮脂中的残留量显著低于肝脏和肾脏,停药9d时,残留量低于药物残留限量。综合各组织中总残留量和最高残留限量规定,建议磺胺对甲氧嘧啶和二甲氧苄啶预混剂在鸡的休药期为7d。     

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.     

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.     

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.     

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.     

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.