泰地罗新在猪体内的药物动力学及生物利用度研究

为了探究泰地罗新在猪体内的药物动力学特征以及口服生物利用度,本试验通过给猪单次口服和静脉注射泰地罗新,来研究泰地罗新在猪体内的药物动力学特征以及生物利用度。试验结果显示,泰地罗新口服在猪体内吸收半衰期(t1/2ka)为1. 057 h,消除半衰期(t1/2β)为80. 9h,达峰时间(Tmax)为2. 10 h,峰浓度(Cmax)为0. 51μg/m L,其吸收快,消除半衰期长,单次口服给药可长时间维持较高的血药浓度,口服给药在猪体内的生物利用度为72. 9%。研究表明,说泰地罗新在猪体内的口服生物利用度较高,在猪体内分布广,口服和静注的消除半衰期无明显差异,较为适合口服给药。     

泰地罗新注射液在藏香猪体内的药物动力学研究

为研究泰地罗新在藏香猪体内的药物动力学特征,了解其在藏香猪体内的吸收、分布、转化及排泄规律,为泰地罗新注射液的临床合理用药提供参考。本试验选取8头藏香猪,泰地罗新单剂量注射给药,不同时间点采集藏香猪血液,利用高效液相色谱法测定血浆中药物浓度。结果表明：泰地罗新注射给药(4 mg/kg.bw)后,泰地罗新在藏香猪体内的药-时曲线符合有吸收三室开放模型,其主要药动学参数为：Tmax为0.457±0.143h,Cmax为0.759±0.192 μg/mL,t1/2为120.518±10.181h,AUC为22.224±2.641μg.h/mL。表明泰地罗新注射给药后,在藏香猪体内吸收迅速,消除较为缓慢。     

泰地罗新注射液治疗猪呼吸道疾病临床疗效试验

为评价泰地罗新注射液注射液(4%)对猪呼吸道疾病的有效性和安全性,试验选择自然发病、表现典型的呼吸系统疾病症状的130头猪进行治疗效果试验。将患病猪随机分成2组(试验组和对照组),受试组采用泰地罗新注射液(4 mg/kg体重)肌内注射给药,对照组采用氟苯尼考注射液(2 mg/kg体重)肌内注射给药。结果显示:受试组和对照组给药后,对猪呼吸道疾病的有效率分别为86.15%和78.46%,治愈率分别为83.08%和75.38%,死亡率分别为10.77%和16.92%。泰地罗新注射液与氟苯尼考注射液相比,疗效更好,死亡率较低。泰地罗新注射液对自然感染副猪嗜血杆菌和胸膜肺炎放线杆菌等引起的呼吸道疾病具有良好的治疗效果。     

泰地罗新注射液在藏系羊体内的药物代谢动力学研究

为研究泰地罗新注射液在藏系羊体内的药物动力学特征,了解其在藏系羊体内的吸收、分布、转化及排泄规律,为泰地罗新注射液的临床合理用药提供参考,选取8只藏系羊,泰地罗新4 mg/kg体重单剂量肌内注射给药,不同时间点采集藏系羊血液,利用高效液相色谱法测定血浆中药物浓度。结果显示:给药后泰地罗新在藏系羊体内的药-时曲线符合有吸收三室开放模型,其主要药动学参数为:达峰时间(T_(max))为(0.723±0.186)h,最高血药浓度(C_(max))为(0.769±0.231)μg/m L,半衰期(t_(1/2))为(86.525±10.547)h,表观分布容积(Vd)为(15.298±2.564)m L/kg,药时曲线下面积(AUC)为(28.738±3.452)μg·h/m L。结果表明:泰地罗新注射给药后,在藏系羊体内吸收迅速,消除较为缓慢。     

泰地罗新注射液对猪传染性胸膜肺炎的临床疗效试验

将泰地罗新注射液分为高、中、低（8、4、2 mg /kg bw）3个剂量组分别肌肉注射治疗猪传染性胸膜肺炎,同时设默沙东动物保健品有限公司的泰地罗新注射液为对照组,按4mg /kg bw给药,给药一次。结果表明,泰地罗新注射液中（4mg/kg bw）、高（8mg/kg bw）剂量对人工感染传染性胸膜肺炎病猪的有效率和治愈率无显著差异（P＞0.05）,与默沙东动物保健品有限公司生产的泰地罗新注射液推荐剂量（4mg/kg bw）的效果相当。试验结果表明泰地罗新注射液按一次量,每1 kg体重4mg肌注,对猪传染性胸膜肺炎有良好的治疗效果。     

肌肉注射泰地罗新注射液对仔猪血液生化指标的影响

为评价泰地罗新注射液的安全性,将40头二元杂交仔猪随机分为4组,每组10头,分别为对照组(生理盐水)、泰地罗新注射液低剂量组(4 mg/kg)、泰地罗新注射液中剂量组(8 mg/kg)和泰地罗新注射液高剂量组(12 mg/kg)。在第0天、第7天和第14天经肌肉注射给药,并在给药前、首次给药后的第7天、第14天和第21天采取仔猪的静脉血后,应用生化分析仪检测静脉血中谷丙转氨酶、谷草转氨酶、总蛋白、白蛋白、白球比和胆红素6种血液生化指标,探究泰地罗新注射液对仔猪肝脏功能的影响。试验结果显示:首次给药后第7天、第14天和第21天,泰地罗新注射液低剂量组(4 mg/kg)的总胆红素含量显著降低;在给药后第21天,泰地罗新注射液低剂量组(4 mg/kg)和泰地罗新注射液中剂量组(8 mg/kg)白蛋白含量显著升高;在给药后第21天,泰地罗新注射液中剂量组(8 mg/kg)的总蛋白含量显著升高;其余各组各项血液生化指标均差异不显著。泰地罗新注射液能够降低仔猪肝脏的氧化损伤,促进仔猪对蛋白质的消化吸收和代谢。     

猪温病热盛证动物模型的建立

筛选猪温病发热模型的造模方法并确定临床症状评定标准。以呋塞米注射液、脂多糖(LPS)、大肠杆菌菌悬液为致模因素,采用3种不同方法进行造模,即猪耳缘静脉注射呋塞米注射液(0.05 mL/kg BW),再以LPS(0.5μg/kg BW、1.5μg/kg BW)耳缘静脉注射攻毒;猪耳缘静脉注射LPS(1.5μg/kg BW),再以大肠杆菌菌悬液(0.3 mL/kg BW、0.5 mL/kg BW)耳缘静脉注射攻毒;猪耳缘静脉注射大肠杆菌菌悬液(0.3 mL/kg BW、0.2 mL/kg BW)进行攻毒。观测猪直肠温度、呼吸、饮食、精神、呕吐等情况。结果显示,注射呋塞米注射液与不同剂量LPS未制造出猪温病的全部临床症状;同时注射LPS与不同剂量大肠杆菌菌悬液能复制出猪温病模型,但大肠杆菌菌悬液0.5 mL/kg BW剂量组动物存在死亡,且LPS与大肠杆菌菌悬液均有致热之效;注射不同剂量的大肠杆菌菌悬液,剂量为0.3 mL/kg的大肠杆菌菌悬液即能有效复制出猪温病模型。结果提示,猪按0.3 mL/kg BW的剂量,经耳缘静脉单次注射浓度为2×10⁹ cfu/mL的大肠杆...     

泰地罗新注射液在藏鸡体内的药动学研究

为研究泰地罗新注射液在藏鸡体内的药物动力学特征,了解其在藏鸡体内的吸收、分布、转化及排泄规律,试验选取藏鸡12羽,泰地罗新单剂量注射给药(4 mg/kg.bw),不同时间点采集藏鸡血液,利用高效液相色谱法测定血浆中药物浓度。结果表明:注射给药后,泰地罗新在藏鸡体内的药-时曲线符合有吸收三室开放模型,其主要药动学参数:T_(max)为(1.727±0.237)h,C_(max)为(0.938±0.121)μg/m L,t_(1/2)为(36.198±2.394)h,AUC为(55.564±3.675)μg·h/m L,V_d为(16.155±2.676)m L/kg,表明泰地罗新注射给药后在藏鸡体内吸收迅速,消除较为缓慢,对新兽药的研发和临床合理使用具有一定的指导意义。     

牛皮下注射卡洛芬注射液的药动学试验研究

为研究卡洛芬注射液在牛体内的药动学特征,将8头健康牛随机分为两组,每组4头,给药剂量为1.4 mg/kg BW,给药后按设计的采血点采集血样,采用超高液相色谱-串联质谱法(UPLC-MS/MS)测定血浆中卡洛芬的药物浓度,用WinNonlin8.1软件计算药动学参数。结果显示：牛单次皮下注射受试制剂卡洛芬注射液在牛体内主要药动学参数如下：平均最高血药浓度(Cmax)为(17473.30±2398.73)ng·mL^-1,平均药时曲线下面积(AUClast)为(1052647.93±143055.37)h·ng·mL^-1,平均达峰时间(Tmax)为8.00±2.62 h,平均消除半衰期(T_1/2)为55.69±3.25 h;牛单次皮下注射参比制剂卡洛芬注射液的主要药动学参数如下：平均最高血药浓度(Cmax)为(15695.98±4865.73)ng·mL^-1,平均药时曲线下面积(AUClast)为(1002858.15±297235.31)h·ng·mL^-1,平均达峰时间(Tmax...     

家兔大椎穴注射扑热息痛的药动学研究

目的:研究扑热息痛注射液于家兔大椎穴注射后的药动学特征。方法:健康家兔8只,扑热息痛单剂量(20mg/kg)于大椎穴注射后,在规定时间点采血,HPLC检测血药浓度,DAS药动学软件处理药时数据。结果:药时数据符合一级吸收二室模型(权重=1/C2),主要药动学参数为:Cmax=23.1880±2.4785(mg/l),tpeak=0.5000±0.0000(h),t1/2Ka=0.3821±0.1086(h),t1/2α=2.1260±0.9838(h),t1/2β=10.1621±4.0967,AUC(0-12h)=34.5331±4.181(mg/l.h),Ka=3.7364±1.2723(h),MRT(0-12h)=1.3159±0.0581(h)。结论:扑热息痛于家兔大椎穴注射后,药物迅速达到峰值,血药浓度高,有效血药浓度维持时间长,药物体内分布广泛。     

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.     

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.     

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     

Evaluation of the Microbiological Status of Milk and Various Structures in Mammary Glands from Naturally Infected Dairy Cows

A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.     

Development and survival of free-living stages of gastrointestinal nematodes of sheep and goats on pasture in the Nigerian derived savanna

Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L₃) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L₃ developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.