柴黄口服液长期毒性试验研究

为了考察柴黄口服液安全性,以大鼠为试验动物,分别在其饮水中连续添加20 mL/L(推荐剂量20倍)、40 mL/L(推荐剂量40倍)、80 mL/L(推荐剂量80倍)的柴黄口服液,对其长期毒性进行了为期90 d的饲喂考察。结果表明,新兽药柴黄口服液的所有用药组大鼠,在为期90 d的试验过程中,其临床表现、增重和饲料利用、脏器指数、血液学常规、血液生化检查及组织病理学六方面均与不用药对照组无显著差异(P0.05),综上所述该药长期使用是安全的。     

板芪口服液急性毒性及长期毒性试验研究

探讨新兽药板芪口服液的急性毒性与长期毒性,评价其安全性。小鼠灌服板芪口服液进行急性毒性预试验,未获得动物的半数致死量,遂以最大给药剂量(270 g生药·kg~(-1)体重)进行急性毒性试验。将80只大鼠随机分为板芪口服液低、中、高剂量组和空白对照组,每组20只,雌雄各半,进行长期毒性试验。分别以10 g生药·kg~(-1)体重(猪临床推荐剂量的20倍)、20 g生药·kg~(-1)体重(猪临床推荐剂量的40倍)、40 g生药·kg~(-1)体重(猪临床推荐剂量的80倍)给大鼠灌服,对照组灌服等体积蒸馏水,给药容积为1 m L·100 g~(-1)体重,每天1次,连续给药30 d,期间观察大鼠外观体征及行为活动。停止给药24 h和15 d后进行剖检、血液生化检查和病理组织切片观察。结果显示,板芪口服液急性毒性试验评价为无毒,长期毒性试验中各剂量组大鼠的观察指标和测定指标与空白对照组相比均无显著差异,表明板芪口服液安全无毒,可用于临床试验。     

葛根芩连口服液体外抑菌及体内免疫调节作用的试验

试验研究葛根芩连口服液体外抑菌及体内免疫调节作用。选用21日龄仔猪40头,随机分为4组,每组10头。Ⅰ组为对照组,Ⅱ、Ⅲ、Ⅳ组为饮水中添加葛根芩连口服液,添加量分别为0.2,0.4,0.7 m L/L,同时采用双倍稀释法,测定葛根芩连口服液对大肠杆菌、沙门菌及肠球菌的药敏试验。结果表明,体外抑菌初步考察结果显示,葛根芩连口服液对肠球菌、沙门菌、大肠杆菌均有抑制作用,其MIC值分别为20.83μg/m L、41.7μg/m L、62.5μg/m L,抑菌效果强于单独的葛根、黄芩、黄连提取液及硫酸粘杆菌素。同时仔猪血清中IL-1、IL-4、TNF-α、TNF-γ细胞因子水平有不同程度的提高(P0.05)。结果提示,葛根芩连口服液能提高仔猪血清中细胞因子水平及机体免疫功能,并且对大肠杆菌、沙门菌、肠球菌具有良好体外抑菌作用。     

鱼腥草芩蓝口服液的毒理学研究

为了评价鱼腥草芩蓝口服液的毒性,为临床安全用药提供依据。以昆明小鼠和SD大鼠为研究对象进行鱼腥草芩蓝口服液急性和长期毒性试验。急性毒性试验中,采用最大给药量试验,以健康小鼠20只,24 h内按68 g/kg体重灌胃给药3次,给药后连续观察10 d,测定其最大给药量。长期毒性试验中,将80只健康大鼠随机分为对照组和高、中、低剂量组,每组雌雄各10只。对照组按20 m L/kg灌服生理盐水,给药组分别按34、17和8.5 g/kg灌服鱼腥草芩蓝口服液,每天一次,连续给药35 d。结果显示,小鼠灌服鱼腥草芩蓝口服液的最大给药量为204 g/kg。鱼腥草芩蓝口服液对试验大鼠的精神状态、脏器指数、生理生化指标均没有影响,且对主要脏器也没有明显的病理组织学损伤。结果表明鱼腥草芩蓝口服液在临床应用是安全的。     

非泼罗尼的药物性能及对犬类的安全性试验

为研究非泼罗尼的药物性能及对犬类动物的安全性,试验选用本地杂种犬40只,随机分为四组,每组10只。分别给予推荐剂量的生理盐水(对照组)和非泼罗尼1倍量组(1.34 m L/犬)、3倍量组(4.02m L/犬)及5倍量组(6.70 m L/犬),每日1次滴于皮肤表面,自然风干,连用3 d。结果显示,非泼罗尼以正常推荐剂量的5倍量连续用药3 d,并无明显毒副作用,血液生化指标无明显影响,尿液检查未见异常。     

术苦芩颗粒对靶动物仔猪的安全性试验

为了评价术苦芩颗粒对靶动物猪的安全性,选取60头健康的20日龄荣昌猪,随机分为4组,每组15头。各试验组分别以1倍(5 g/kg)、3倍(15 g/kg)、5倍(25 g/kg)推荐剂量的术苦芩颗粒连续经口灌胃给药14 d,观察临床症状、增重、血液学和组织病理学变化。结果显示,各组间的血液生理、生化指标无明显差异,组织无明显病理学病变,中剂量组仔猪日增重显著增加(P0.05)。试验表明,术苦芩颗粒安全范围大,在仔猪体内耐受性高,以5倍推荐剂量灌胃14 d对靶动物猪安全。     

地锦草颗粒对鸡的安全性试验

为了评价地锦草颗粒对靶动物鸡的安全性,选取100只健康的10日龄海兰鸡,随机分成5组,每组20只。各组试验鸡分别以1倍推荐剂量(2g/L)、3倍推荐剂量(6g/L)、5倍推荐剂量(10g/L)、10倍推荐剂量(20g/L)的地锦草颗粒连续饮水给药5d,通过对一般临床症状、血液学和血液生化指标、病理组织学等观察和检测,结果表明:地锦草颗粒毒性较小,在鸡体内耐受性高,至少以10倍推荐剂量饮水给药对靶动物鸡是安全的。     

复方氟苯尼考口服液对人工诱发鸡大肠杆菌病的疗效试验

采用 5%复方氟苯尼考口服液对人工诱发的鸡大肠杆菌病进行治疗试验。结果表明 ,5%复方氟苯尼考口服液在剂量为 0 .6 ,0 .3 ,0 .1 5m L/ L给药时 ,能有效的控制鸡大肠杆菌感染 ,缓解症状 ,降低大肠杆菌感染鸡只的发病率和死亡率 ,并在一定程度上减少成活鸡的体重下降 ,效果优于单方的氟苯尼考口服液 ,在临床上有一定的实用价值 ,值得推广使用。临床应用治疗鸡大肠杆菌病推荐剂量为每升水 0 .3 m L。     

芪参口服液的毒理学研究

为评价芪参口服液临床用药的安全性,根据毒理学评价程序和方法对其进行了急性毒性试验和长期毒性试验。在急性毒性试验中,将40只昆明小鼠按体重随机分为2组,采用最大给药量法测定小鼠口服芪参口服液的最大耐受剂量;在长期毒性试验中,将80只Wistar大鼠按体重随机分为4组,3个剂量组分别按3.75、7.5、15 g/kg体重给大鼠灌胃,对照组给予同体积生理盐水,1次/d,连续4周。记录每日饮水量、饲料采食量及每周体重,检测给药4周及停药2周血液生化指标、血常规、脏器系数和组织病理学变化。试验结果显示,小鼠口服芪参口服液的最大耐受剂量为生药量40 g/kg,此剂量相当于临床日用量的40倍。部分给药组采食量和饮水量与对照组相比出现显著(P＜0.05)或极显著(P＜0.01)变化,但对平均周增重无显著性影响(P＞0.05);血常规的部分指标出现显著(P＜0.05)或极显著变化(P＜0.01),但停药2周后,所有指标与相应的对照组相比无显著性差异(P＞0.05);给药组血液生化和脏器系数的各项指标与对照组相比,无显著性变化(P＞0.05)。病理组织学检查无明显差异。试验结果表明,在本次试验条件下,该口服液安全无毒。     

银翘蓝芩口服液对鸡的安全性试验

依据兽药研究技术指导原则,开展银翘蓝芩口服液对靶动物鸡的安全性研究,为其临床应用的安全性提供数据资料。按银翘蓝芩口服液临床推荐剂量的1、3、5倍连续饮水给药7d,给药前后,逐只称重。试验结束后采集血液和组织器官,进行血常规、血液生化指标、脏器指数及病理组织学观察。结果表明,与对照组相比,各给药组鸡只的体重、血常规、血液生化及脏器指数等指标差异均不显著(P0.05),各组织器官未见明显的病理组织学变化。说明银翘蓝芩口服液饮水给药对靶动物鸡是安全的。     

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.     

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.     

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.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein