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1.
The novel ectoparasiticide spinosad is a naturally occurring mixture of spinosyns A and D formed during a fermentation process. The spinosyns are tetracyclic macrolides with a unique ring system. Their mode of action differs from that of other commercially available insecticides. Laboratory and field trials were conducted to evaluate the use of spinosad in a chewable tablet at a dose range of 45 to 70 mg/kg for the treatment and control of flea infestations on dogs in Europe. Laboratory studies with artificially infested dogs confirmed persistent activity against Ctenocephalides felis of higher than 99 per cent at three weeks post-treatment with values of 96.5 to 97.8 per cent at four weeks. Two multicentric field trials with naturally infected client-owned animals in five European countries used selamectin as comparator. Monthly doses were given during the summer when many homes were heavily infested. Households with spinosad-treated dogs showed cumulative benefits with flea burdens reduced by about 97 per cent at 14 and 30 days and by 99.6 per cent at 60 and 90 days. Corresponding figures for selamectin were significantly lower (P<0.05) at all time points: between 88.5 and 91 per cent at 14 and 30 days, then 97.8 and 98.2 per cent at 60 and 90 days. Thus, the performance of spinosad compared favourably with that of the established reference product.  相似文献   

2.
断奶羔羊4种必需氨基酸限制性顺序和需要量模型探索   总被引:1,自引:0,他引:1  
本试验旨在采用氨基酸部分扣除法研究断奶羔羊的4种必需氨基酸的限制性顺序和需要模型。选取50日龄断奶湖羊公羊100只随机分为5组,每组4个重复,每个重复5只羊。对照组为氨基酸平衡(PC)组,饲喂氨基酸平衡的开食料,4个试验组开食料在PC组的基础上分别扣除赖氨酸(PD-Lys组)、蛋氨酸(PD-Met组)、苏氨酸(PD-Thr组)和色氨酸(PD-Trp组),其余氨基酸含量保持一致。预试期为10 d,正试期为60 d。于羔羊60、90和120日龄称量体重,在120日龄每组随机选取6只羔羊进行屠宰。结果表明:1)60~120日龄和90~120日龄,PD-M et组羔羊平均日增重(ADG)显著低于其他各组(P0.05),饲料转化率(F/G)显著高于其他各组(P0.05);120日龄时,PD-Met组宰前活重、空体重、胴体重、眼肌面积、头重、蹄重及皮毛重均显著低于PC、PD-Thr和PD-Trp组(P0.05),但是5组间屠宰率(DP)、GR值和血液重差异不显著(P0.05)。2)以最佳ADG和F/G为评价指标时,60~90日龄和90~120日龄氨基酸限制性顺序为Met、Lys、Thr和Trp;而以最佳DP为评价指标时,120日龄氨基酸的限制性顺序为Trp、Thr、Lys、Met。3)以最佳ADG作为评价指标时,60~90日龄和90~120日龄Lys、M et、Thr和Trp的适宜比例分别为100∶44∶44∶8和100∶42∶38∶12;以最佳F/G作为评价指标时,60~90日龄和90~120日龄Lys、M et、Thr和Trp的适宜比例分别为100∶54∶45∶7和100∶47∶39∶12;以最佳DP为评价指标时,60~120日龄Lys、M et、Thr和Trp的适宜比例为100∶34∶38∶8。总之,饲粮必需氨基酸(Lys、Met、Thr和Trp)缺乏严重影响湖羊断奶羔羊的生长性能、屠宰性能和器官指数,特别是Met影响最为明显,其次是Lys,Thr和Trp影响较弱;不同评价指标(ADG、F/G和DP)和不同生长阶段得出的Lys、M et、Thr和Trp的限制性顺序和需要模型是不同的。  相似文献   

3.
四种药物治疗人工感染鸡卡氏住白细胞虫病的试验   总被引:1,自引:0,他引:1  
通过实验室人工攻虫治疗试验,比较验证血虫净、克球粉、泰灭净和痢特灵四种药物对鸡卡氏住白细胞虫病的治疗效果.结果,血虫净和泰灭净治疗效果最好,治愈率皆为100%,且血虫净不影响蛋鸡的产蛋,但泰灭净则影响产蛋,因此,泰灭净应慎用.用血虫净治疗临床上确诊为鸡卡氏住白细胞虫病的病鸡,跟踪观察,结果临床治愈率达99%以上,因此,血虫净是治疗该病的首选药.  相似文献   

4.
On dairy calves (totally 35 animals; 14 male; 21 female) measurements of rectal temperature, heart rate and blood values (acid-base balance, Hb, Hk, MCHC, gas content and gas pressure, hemoglobin derivatives, cortisol, total protein, albumin, blood urea, creatinine, glucose, lactate, Ca, Mg, P, Fe) and of salivary cortisol were done before and after i.v. ACTH application and liquid feed intake at 5, 15, 40 and 60 days of life age. Mean values of P-cortisol, S-cortisol, heart rate and COHb were elevated and those of total protein, albumin, Mg, Hb, Hk, O2CAP were decreased after i.v. ACTH and feed intake. Mean glucose and P concentration changed differently in younger and older calves after ACTH and liquid feed intake. Changes of Ca and Fe concentration were not significant at all age points. Effects of gender could be found for cortisol, O2CONT, MCHC, total protein, creatinine, lactate, Mg, and Ca at some age points. Initial P-cortisol levels were higher at 5 and 15 days than at 40 and 60 days of life, the levels after stimulation were higher at 5 days than at 15, 40 and 60 days. Initial levels of S-cortisol were significantly different between all age points, the levels after stimulation were not different. Female calves had significantly greater P-cortisol values at 40 and 60 days as male calves and at 40 days greater S-cortisol values too. Significant correlations between P-cortisol and S-cortisol could be found before stimulation (5 days: r = 0.626; 15 days: r = 0.366; 60 days: r = 0.357) not thereafter. All measures except P-cortisol, S-cortisol, O2SAT, and HHb had significant correlations before and after ACTH and liquid feed intake indicating great interindividual variation and individual specificity of reaction within this growth period. Results were discussed under the viewpoint of reactivity of adrenocortex and steroid distribution concerning organ specific effects of steroids in calves.  相似文献   

5.
Suckler calves from a cow-calf operation (German Red Pied, German Black Pied) were used repeatedly for separation, transport and isolation (TSI) experiments of 60 min duration at five life ages. Measurements of body weight, body temperature and heart rate were combined with blood sampling before TSI, and at the end of the isolation period of one hour duration as well. Effects of gender, age and body weight on the variables and on the changes of the variables were tested. Characteristic heart rate values showed the increasing excitement and the motor activation of the animals in case of transport and of manipulations and the periods of relative rest within the isolation room as well. Mean noradrenalin concentration was significantly lower after TSI at all age points, mean adrenalin concentration was significantly higher after TSI at 9-14 days and significantly lower at 59-77 days of age than before. Changes of adrenalin concentration were significantly influenced by body weight and age. Sex, body weight and age had significant effects on hemoglobin (Hb), hematokrit (Hk), mean corpuscular hemoglobin concentration (MCHC), oxygen capacity (O2CAP) and oxygen contents (O2CONT). Hb, Hk and O2CAP were significantly diminished after TSI at all age points, O2CONT and oxygen saturation (O2SAT) were significantly increased after TSI at many age points. Shrinking of body weight after TSI was always significant and was significantly affected by body weight before TSI and by age. Body weight and age had significant effects on body temperature and its changes after TSI.  相似文献   

6.
7.
Calves from the dairy herd of the institute reared in groups with changing (Gw, N 16, m 9, w 7) and constant composition (Gk, N 16, m 9, w 7) since the first day of life and single box reared calves (E, N 11, m 7, w 4) were tested at 15, 30, 60 and 90 days of age. Venous blood samples were analysed for total protein, albumin, creatinine, blood urea, glucose, Ca, Mg, P and iron. At 15 days between group differences of mean values existed for total protein, albumin, blood urea, creatinine and at 30 days for rectal temperature, albumin, blood urea, Ca, P and Fe, at 60 days for blood urea, glucose, Ca, Mg, P and at 90 days for total protein, albumin, creatinine, glucose, Mg and P. Interactions between group and gender could not be demonstrated. Significant changes of variables with age were most frequent in calves of group Gk, and more frequent with creatinine, blood urea, Fe and glucose. Creatinine concentration diminished permanently with age of the animals, that one of total protein and albumin increased moderately. Blood urea was higher at 90 days, and serum iron at 60 and 90 days than before. Blood glucose concentration at 90 days was lower in calves of group Gw and Gk comparing group E. Significant group differences appeared at 15 days (total protein, albumin, blood urea, creatinine) and remained till 60 days (blood urea) and 90 days (total protein, albumin) or became stronger at 90 days (creatinine). Total protein, albumin and blood urea were higher in group E than in group Gk and Gw calves. Group Gw calves had smallest glucose concentrations at 60 and 90 days. Significant between groups differences for Ca, Mg, P existed for all sampling points, those for serum iron at 30 days only. Greater Ca and Mg values were found in group Gk and group E calves, greater P concentrations up to 60 days of age in group E calves. P concentrations changed differently in group Gk and group Gw calves with age. Creatinine showed moderately high between sampling point correlations. Changes of variables in calves between age points in relation to the starting situation at 15 days of age showed significant correlations in many cases meaning that there were directed individual and time specific adaptation processes.  相似文献   

8.
A study was carried out at the Okpara breeding farm in Benin. Records on 558 lambs of the Djallonke sheep breed, born from 1997 to 2000, were used to determine the weekly growth curve from birth up to 119 days of age. Non-genetic factors affecting lamb weights at birth and at 30, 60, 90 and 120 days and average daily gains from 0 to 30 days, from 0 to 60 days, from 0 to 90 days and from 0 to 120 days were investigated. A linear model comprising the fixed effects of birth season, birth year, parity number of ewe and sex of lambs was used for analysis of variance by least squares. All fixed effects were significant for weight at 30 and 60 days and average daily gains at 30 days, with the exception of the parity of the ewe for birth weight, weight and average daily gain at 90 days. All fixed effects tended to cancel out for weight and average daily gains by 120 days. Lambs born in the dry season were the heaviest. Single lambs and male lambs were heavier than twins and females. Lambs from ewes of 3rd and 4th parity were heavier, with higher, average daily gains.  相似文献   

9.
The effects of carbamazepine and sodium valproate on fertility of male rats were studied. The tested drugs were given orally to male rats for 30 and 60 consecutive days. Mating performance, sex organs weights, semen quality, plasma concentrations of sexual hormones as well as histopathological findings were the criteria used to evaluate the reproductive efficiency of treated males. Oral administration of carbamazepine and sodium valproate for 30 and 60 consecutive days significantly decreased the testicular weight, sperm cell concentration, live sperms and percentage of progressively motile spermatozoa. Both drugs significantly increased the percentage of morphologically abnormal spermatozoa. A decrease in plasma testosterone, FSH and LH and an increase in prolactin levels were observed in the treated groups. Histopathological examination showed mild to moderate degenerative changes in the testes of the treated rats while the prostate glands and seminal vesicles appeared normal. A recovery period of 30 days was accompanied by marked changes in the tested parameters towards initial values.  相似文献   

10.
Persistence of avian influenza viruses in water   总被引:9,自引:0,他引:9  
Persistence of five avian influenza viruses (AIVs) derived from four waterfowl species in Louisiana and representing five hemagglutinin and neuraminidase subtypes was determined in distilled water at 17 C and 28 C. Infectivity was determined over 60 days by microtiter endpoint titration. One AIV was tested over 91 days at 4 C. Linear regression models for these viruses predicted that an initial concentration of 1 x 10(6) TCID50/ml water could remain infective for up to 207 days at 17 C and up to 102 days at 28 C. Significant differences in slopes for AIV persistence models were detected between treatment temperatures and among viruses. Results suggest that these viruses are adapted to transmission on waterfowl wintering habitats. Results also suggest a potential risk associated with waterfowl and domestic poultry sharing a common water source.  相似文献   

11.
Cloprostenol, a prostaglandin analogue, was administered intramuscularly to a total of 35 cycling buffalo cows and heifers in two doses, each of 0.5 mg, given 11 days apart. Out of five cows and 12 heifers subjected to observations after the second injection of cloprostenol (day 0), all except one heifer responded. Signs of oestrus were most marked on days 3 or 4. Eighteen treated heifers were kept with buffalo bulls for four days after the second injection while a control group of nine heifers was kept with bulls for 21 days. The first-service conception rate, diagnosed by rectal palpation at 60 days, was 33 1/3 per cent in both groups. Twelve treated heifers were artificially inseminated at 72 and 96 hours after the second injection of cloprostenol, using fresh semen diluted in egg yolk--citrate extender. The first service conception rate at 60 days was 30 per cent.  相似文献   

12.
OBJECTIVE: To evaluate in vivo activity of carprofen, deracoxib, and etodolac on prostanoid production in several target tissues in dogs with chronic osteoarthritis. ANIMALS: 8 dogs with chronic unilateral osteoarthritis of the stifle joint. PROCEDURE: Each dog received carprofen, deracoxib, or etodolac for 10 days with a 30- to 60-day washout period between treatments. On days 0, 3, and 10, prostaglandin (PG) E2 concentrations were measured in lipopolysaccharide-stimulated blood, synovial fluid, and gastric mucosal biopsy specimens; PGE1 concentrations were measured in gastric mucosal biopsy specimens; and thromboxane B2 (TXB2) was evaluated in blood. RESULTS: Carprofen and deracoxib significantly suppressed PGE2 concentrations in blood at days 3 and 10, compared with baseline, whereas etodolac did not. None of the drugs significantly suppressed TXB2 concentrations in blood or gastric PGE1 synthesis at any time point. All 3 drugs significantly decreased gastric synthesis of PGE2 at day 3 but not day 10 of each treatment period. All 3 drugs decreased synovial fluid PGE2 concentrations in the affected and unaffected stifle joints at days 3 and 10. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that carprofen and deracoxib act in vivo on target tissues as COX-1-sparing drugs by sparing gastric PGE1 and PGE2 synthesis and production of TXB2 by platelets. Etodolac also appears to be COX-1 sparing but may have variable effects on COX-2 depending on the tissue. In gastric mucosa and synovial fluid, there were no significant differences in PG production between compounds at recommended concentrations.  相似文献   

13.
柔嫩艾美球虫常州株对5种抗球虫药的抗药性分析   总被引:2,自引:1,他引:1  
将柔嫩艾美耳球虫(E.tenella)常州分离株感染14日龄苏禽黄羽肉鸡,设立5个用药组、1个感染不用药对照组和1个不感染不用药对照组,以相对卵囊产量、病变记分减少率、最适抗球虫百分数和抗球虫指数为指标对该虫株对球虫宁、地克珠利、马杜霉素、磺胺氯吡嗪、癸氧喹酯5种常用抗球虫药的抗药性进行了综合评定,分析了该地区球虫的抗药性及用药对策。结果表明,该虫株对癸氧喹酯敏感,对球虫宁、地克珠利、马杜霉素、磺胺氯吡嗪具有完全抗药性,提示目前常州地区球虫抗药性非常严重,癸氧喹酯抗球虫疗效最好,其他药物应合理使用、应慎用、减少或暂停使用。  相似文献   

14.
脂质体在医用生物学中的研究与应用   总被引:1,自引:0,他引:1  
脂质体作为一种对机体无毒、无免疫原性的定向药物载体,它既能包封脂溶性药物,又能包封水溶性药物;减轻变态反应和免疫反应;延缓释放,延长药物在体内的半衰期;能有效地保护被包裹药物,提高生物利用度;改变药物在体内的分布,并能靶向性释药,降低药物的毒副作用;适合多途径给药等特点。文章论述了脂质体作为药物载体、基因工程载体、疫苗载体、免疫诊断、基因治疗和核酸免疫中的DNA载体等在医用生物学中的研究应用,并扼要介绍了近年来脂质体的最新发展动态,表明了脂质体制剂在医用生物学研究中广阔的应用前景。  相似文献   

15.
The effects of severe respiratory disease on the disposition of antibiotics were evaluated using two drugs chosen because of their widely differing solubility characteristics. The experiments were carried out in series, using five calves for each drug. The drugs were given to seven week old calves before and after induction of pneumonia by bilateral intrapulmonary administration of 3 mL of 5 X 10(7) colony forming units of Pasteurella haemolytica. Following inoculation, the calves developed clinical signs of pneumonia and were given gentamicin (5 mg/kg) or tylosin (10 mg/kg) 48, 60 and 72 hours after Pasteurella administration. There was a statistically significant decrease in distribution rate but not elimination rate of gentamicin. For tylosin, there was a significant increase in elimination rate. These results indicate the kinetics of tylosin but not gentamicin are sufficiently altered as to support a need for increased frequency of administration with severe respiratory disease in calves.  相似文献   

16.
本试验旨在研究不同相对湿度(RH)对间歇性26℃环境下肉鸡盲肠菌群多样性的影响。选取29日龄爱拔益加(AA)肉鸡180只转入环境控制舱,随机分成3个组(RH分别为30%、60%和85%),每组6个重复,每个重复10只鸡(公母各5只)。从29日龄开始,每天10:00—16:00(6 h)温度维持26℃,RH分别为30%、60%和85%,剩余时间温度为21℃,RH为60%。试验共14 d。采用16S rDNA的变性梯度凝胶电泳(DGGE)技术,结合特异性和共性条带割胶回收DNA进行克隆和测序,分析RH在间歇性26℃偏热处理第7天和第14天时对盲肠内容物菌群结构和多样性的影响。结果表明:1)试验第7天,30%RH组肉鸡盲肠DGGE条带数(菌群丰富程度)高于60%RH组,而85%RH组低于60%RH组;试验第14天,30%、85%RH组肉鸡盲肠DGGE条带数均高于60%RH组。2)聚类分析显示,试验第7天,85%RH对盲肠菌群影响明显;试验第14天,30%RH对盲肠菌群影响明显。但随着处理时间推移,30%RH对肉鸡盲肠菌群影响越大。3)间歇性26℃环境下不同RH组肉鸡盲肠内共性菌群是Faecalibacterium prausnitzii;在试验第7天,30%、85%RH组肉鸡盲肠中特异性菌群是Stomatobaculum longum。结果提示:间歇性26℃环境下,低湿(30%RH)和高湿(85%RH)影响肉鸡盲肠菌群的结构和多样性,且不同处理时间RH的影响不同  相似文献   

17.
Differences between neonatal and adult animals in their response to drugs can usually be attributed to altered disposition (ie, distribution, metabolism and excretion) processes during the neonatal period. These alterations affect the plasma concentrations as well as the concentrations of drug attained at the receptor site. Some characteristics of the neonatal period include greater absorption from the gastrointestinal tract, lower extent of plasma protein binding, increased apparent volume of distribution of drugs that distribute in extracellular fluid or total body water, increased permeability of the 'blood-brain' barrier and slower elimination of many drugs. The hepatic microsomal oxidative reactions and glucuronide conjugation are deficient metabolic pathways for a varying period of time, usually up to six weeks after birth or even longer in some species. Decreased metabolism can affect the duration of action of lipid-soluble drugs. Functional immaturity of the kidneys decreases the renal excretion of polar drugs and drug metabolites. Overall renal function appears to reach maturity within two weeks after birth in ruminant species and pigs, while maturation may take at least four weeks in other species of domestic animals. Considerable physiological and biochemical development takes place during the first five days after birth with maturation continuing more slowly over the succeeding five weeks. The time it takes for any process to reach functional maturity depends on the process in question and varies with the species of animal. The absorption, disposition and pharmacological response to drugs during the first 24 h after birth may be unique to that time and, because of lack of information, are impossible to predict.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
Nine previously vaccinated turkeys were inoculated intravenously with Pasteurella anatipestifer, and blood samples were taken periodically to evaluate the potential of chronically infected turkeys to serve as reservoirs of infection for blood-feeding arthropod vectors. Vertebral osteomyelitis (spondylitis), as yet unreported in the literature in association with infection with the organism, was found in the thoracic vertebrae of five out of nine inoculated turkeys, and P. anatipestifer was isolated from the thoracic vertebrae of three of the five. The organism was isolated from the peripheral blood of six turkeys 24 hours postinoculation and from the peripheral blood of one turkey 7 days postinoculation. The organism was also isolated from the heart blood of two birds at necropsy--from one at 21 days and, following an intramuscular injection of dexamethasone, from the other turkey at 38 days postinoculation.  相似文献   

19.
The serological changes in two groups of horses known to be harbouring Anoplocephala perfoliata were studied; 12 were treated with 1.5 mg/kg praziquantel and 200 microg/kg ivermectin, and 14 were treated with 200 microg/kg ivermectin. Serological and faecal analyses were carried out on each animal at intervals for 758 days. The titres of antibodies specific for A perfoliata decreased from the day of treatment to day 28 in both groups, and continued to decrease in the group treated with praziquantel and ivermectin, with the first significant decrease from the other group at day 121. From day 151 to day 295 the first significant increase in antibody levels in the group treated with both drugs was observed; no A perfoliata eggs were detected in the faeces of these animals until day 295 when five of the 10 were positive.  相似文献   

20.
One hundred and three cats presenting with clinical signs of feline acute upper respiratory Infection were selected from Belgium, France and the Netherlands In a randomised comparative field trial. Each cat underwent a bacteriological examination before treatment (day 0) and received either marbofloxacin, at a dosage of 2 mg/kg once daily for five days, or amoxycillln-clavulanic acid (ACA) at a dosage of 12·5 mg/kg twice dally for five days. Clinical examinations were performed on days 2, 5 and 14. Pasteurella species were cultured in one-third of the samples. The other main bacteria isolated were Streptococcaceae, Enterobacterlaceae and Staphylococcaceae. Response rates (cures + improvements) to treatment on day 5 were 87·8 vs 77·8 per cent for marbofloxacin and ACA, respectively. A few mild side-effects (diarrhoea, vomiting) were recorded with both drugs.  相似文献   

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