甘南地区羊泰勒虫病的预防与治疗试验

2004年-2005年在甘南藏族自治州羊泰勒虫病流行的农区、半农半牧区及半林半牧区，进行最佳灭蜱药物试验和治疗羊泰勒虫病效果对比观察试验。结果表明：最佳灭蜱药物是长效阿力佳注射液和灭蜱灵油剂，平均有效期分别为44d、36d，灭蜱预防后发病率降到5．00％、2．86％；蒿甲醚、血虫克星、焦虫净及贝尼尔注射液对羊泰勒虫病的治愈率分别为92．30％、91．76％、90．47％7和90．43％，其治疗效果均较好，特别对发病初期轻症病羊治疗效果好。     

灭蜱灵等五种灭蜱药物的试验观察

经流行病学调查,甘肃省中部地区羊血液原虫病的主要致病病原为羊泰勒虫.该病是一种季节性很强的严重危害牛羊等家畜的蜱传性血液原虫病.预防本病的关键在于及时有效地灭蜱.为此我们在羊血液原虫病高发的四个县选用倍特、螨净、虫克星、碘硝酚和灭蜱灵5种药物进行了羊只体外灭蜱药物的筛选与应用试验.     

甘南藏族自治州山羊泰勒虫病的调查及防治

目的了解羊泰勒虫病在甘南州的流行情况并进行有效防治。方法采用血液涂片、ELISA、PCR三种方法进行了本病的流行病学调查,其中ELISA的检出率最高,为69．50％。在药物防治试验中,对3种灭蜱药物进行了灭蜱效果对比,对4种抗原虫药物进行了治疗效果对比。结果最佳灭蜱药物是长效百虫净,灭蜱有效期为48天,预防效果达92.30％;最佳治疗药物是长效弓血灵,治愈率达90．77％。结论甘南州山羊泰勒虫病发病率较高,要以灭蜱和治疗相结合的方法来有效控制本病的发生。     

羊泰勒虫病的预防与治疗试验

研究如何对羊泰勒虫病进行有效的预防以及治疗。方法:从羊泰勒虫病流行较为严重的村中选择480只年龄在1岁以内的羊只,将其随机分为5组,每组各96只,分别对其采用不预防、灭蜱灵乳油、灭蜱灵乳油+伊利加注射液、灭蜱灵乳油+多拉菌素注射液、灭蜱灵乳油+多拉菌素+血虫净等方法进行预防;选取2018年1～12月发生羊泰勒焦虫病的羊只共364例。将其随机分为4各小组,每组各91例,分别采用不治疗、血虫净、血虫净+长效土霉素、青蒿琥酯注射液四种方法进行治疗。结果:灭蜱灵乳油+多拉菌素+血虫净的有效灭蜱时间为51d,发病率仅为6.25%,其有效率达87.78%;血虫净与长效土霉素联合治疗效果最佳,其治愈率可达90.11%。     

甘肃省马驽巴贝斯虫病综合防治研究

在查明了30余年来流行甘肃省陇东南地区的一种马病病原为驽巴贝斯虫病，传媒为森林革蜱和草原革蜱的基础上，开展了综合防治研究工作。通过抗血液原虫药物的治疗试验，证明咪唑苯脲、贝尼尔、黄色素、焦虫净对驽巴贝斯虫病的治愈率分别为100％、84．62％、81．82％、73．33％。对贝尼尔用药途径改肌注为静脉滴注后治愈率由84．625提高到90．63％，且副反应大幅度降低，药物预防试验中证明咪唑苯脲、焦虫净、贝尼尔预防效果均达98％以上，有效保护期分别为59、24、24天。应用敌杀死灭蜱预防，效果达100％，有效保护期为23天。成功地研制出了咪唑苯脲缓释剂，其预防效果达100％有效保护期为113天。研究制定了“三双”综合防治措施，在流行区15个县（区）实施3年，共治愈马类家畜119175匹，预防马类家畜905200匹。流行区发病率由13．85％降到0．095，死亡率由5．65％降至0．04％。，获得经济效益8908．98万元。     

贝尼尔缓释剂预防羊泰勒虫病的试验研究

对健康羔羊注射贝尼尔制备的缓释剂,注射液后２个月和３个月分别用感染羊泰勒虫的青海血蜱成蜱进行攻击,结果对照组羔羊全部发病,贝尼尔缓释剂注射组未发病,证明贝尼尔缓释剂能有效地预防羊泰勒虫病。     

牛羊梨形虫病及媒介蜱综合防治药物筛选

天祝县莫客片一带牛梨形虫病发病率达24.6%,病死率28.6%;羊发病率34.2%,病死率27.5%,与往年相比变化不大,笔者从蜱控制、梨形虫病预防加治疗相结合综合防控入手,作控制、预防药物试验对比,筛选药效长、低毒、安全、广谱药物,结果显示用敌杀死环境灭蜱,同时注施可诺注射液控制蜱感染,用蒿甲醚注射液或盐酸咪唑苯脲,预防和治疗梨形虫病,能有效降低当地牛羊梨形虫病的发病率和病死率。     

磷酸伯氨喹和贝尼尔对人工感染羊泰勒虫病例的治疗试验

用感染羊泰勒虫的青海血蜱叮咬健康羊人工复制羊泰勒虫病病例6只，用贝尼尔和磷酸伯氨喹各治疗2只，结果，磷酸伯氨喹以1．5mg/kg体重剂连续肌肉注射3d,2只羊的染虫率分别为从15．0％和10．0％下降到0．5％，临床症状基本消失；贝尼尔以5．0mg/kg体重剂量连续肌肉注射3d仅1只羊的染虫率由12．0％下降到1．5％，临床症状基本消失，1只羊的染虫率由12．0％上升到15．0％，临床症状加重。     

羊泰勒焦虫病预防及对育肥羊生长速度、口蹄疫免疫抗体和母羊繁殖率影响试验

羊泰勒焦虫病是由梨形虫纲、泰勒科、泰勒属的羊泰勒焦虫寄生于羊红细胞和网状内皮系统细胞引起的一种蜱传血液原虫病。临床以高热稽留、发病率高、致死率高为特征。本试验在蜱、焦虫病流行病学调查和蜱驱杀试验基础上,首先对羊泰勒焦虫病进行了预防试验,取得了较好地效果,在此试验基础上又进行了羊泰勒焦虫病对育肥羊生长速度、口蹄疫灭活疫苗免疫抗体和母羊繁殖率影响观察试验,使人们对羊泰勒焦虫病的危害性有进一步深入了解,从而加强对传播者蜱、羊泰勒焦虫病的防控力度,减少羊的发病和死亡,保证养羊业的健康发展,提高养羊的经济效益。     

甘肃省羊泰勒虫媒介蜱的传播试验

用采自羊泰勒虫病疫区甘肃省永靖且的麻点璃眼蜱饥饿成虫叮咬健康羊体，试验羊体内未发现羊泰勒虫；用其饱血雌虫孵化的幼虫叮咬羊泰勒虫感染羊，收集饱血若虫，再用其饥饿成虫叮咬健康羊体，被叮咬羊体内也未查出羊泰勒虫，证明麻点璃眼蜱不传播羊泰勒虫。用采自羊泰勒虫病疫区张家川和永靖县的青海血蜱经人工孵化的幼虫叮咬羊泰勒虫自然感染羊，收集饱血幼虫蜕皮后，用其若虫叮咬健康羊，40d后在被叮咬羊血片中发现羊泰勒虫，但未显示明显的临床症状。用采自羊泰勒虫病疫区羊体的青海血蜱成虫、若虫、幼虫同时叮咬健康羊，18d时在试验羊体内发现羊泰勒虫，试验羊表现贫血、黄疸、稽留热、肩前淋巴结肿大等特征性症状，出现心包积液，肝、脾、肾肿胀及出血的典型病理变化。由此确定，甘肃省的羊泰勒虫是由青海血蜱传播的。     

贝尼尔脂质体和贝尼尔注射剂的急性毒性比较试验

我们试制了贝尼尔脂质体 ,并对其和贝尼尔注射剂进行了小鼠的急性毒性比较试验 ,试验结果表明 ,贝尼尔脂质体的毒副作用显著低于贝尼尔注射剂 ,脂质体组的 L D50 (177.83mg/ kg· bw)显著高于原药组 L D50(74.14m g/ kg· bw) ,是原药组的 2 .40倍。说明贝尼尔制成脂质体后 ,可以显著降低药物毒副作用 ,增加用药的安全性     

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.