首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 234 毫秒
1.
Efficacy of the paramunity inducer Baypamun (PIND-ORF) was evaluated by an IBR challenge trial in cattle, as one model for infectious diseases in bovine. Prophylactic treatment with Baypamun protected cattle against manifestation of clinical symptoms after experimental IBR infection. The degree of protection depended on the time between paramunization and challenge infection. Even in metaphylactically paramunized cattle Baypamun reduced the IBR symptoms. In correlation to the reduction of clinical symptoms paramunization also reduced virus excretion by more than 99% in treated cattle compared to non paramunized animals. The induction of interferon following IBR infection was investigated in paramunized cattle. Application of Baypamun enabled treated animals to react faster with interferon synthesis following IBR infection than control animals did. The demonstration of the status of paramunity following Baypamun application in cattle provides a concept in the prevention of infectious disease in the practice.  相似文献   

2.
The fundamentals of paramunization are briefly discussed to provide better understanding of paramunization of pigs. Veterinary practice and experimental studies demonstrate the usefulness, efficacy and harmlessness of paramunization of pigs. Mortality, morbidity as well as weight gain in piglets are used to evaluate the effect of the inducers PIND-AVI and/or PIND-ORF on piglets which have been treated shortly after birth. The therapeutic effect of paramunization has been studied in herds with enzootic pneumonia. Paramunization is especially suitable in stimulating the immune system, in treating immune deficiencies, in the prophylaxis of the stress syndrome (e.g. induced by transport, weaning, changing stalls, etc.) and in treating pluricausal, multifactorial infectious diseases such as enzootic pneumonia, rhinitis atrophicans, "crowding" disease. Paramunization of pigs is discussed, using PIND-ORF as an example of a biological inducer. Paramunization as a biological method to stimulate immunity provides a new concept of prophylaxis and therapy opposed to the uncontrolled use of chemicals in pig production.  相似文献   

3.
84 FeLV-positive cats were continually treated with the paramunity inducer (immunomodulator) PIND-AVI (23 healthy cats once a week, 61 diseased cats up to 3 times a week), the frequency depending on their general condition. The ELISA control tests were repeated after 4 to 6 weeks. Paramunization was continued in cats still viremic until remission of viremia. 21 healthy cats already reacted negatively to the first control ELISA, the 2 others after 8 weeks of paramunization. Within an observation time of 18 to 30 months there were no relapses. 49 of the 61 diseased cats (80.3%) reacted negatively to the first control. 5 cats (8.2%) had died at the beginning of the treatment. 5 cats (8.2%) showed a remission of viremic after being paramunized continually for 7 to 20 weeks. 2 cats (3.3%) remained viremic throughout the observation time (more than 2 years). None of the animals had a relapse. Neither had any of 9 chronically diseased cats, known to have been viremic for 3 to 12 months at the beginning of paramunization. The importance of the results of these paramunization tests for the treatment of various retrovirus infections of human beings and animals is briefly discussed.  相似文献   

4.
Abstract.— In March 2000, 104 wild caught Litopenaeus wannamei broodstock, captured off the Pacific coast of Panama, were screened for the following penaeid viruses: infectious hypodermal and hematopoietic necrosis virus (IHHNV) and white spot syndrome virus (WSSV). The purpose of this study was to determine the prevalence of IHHNV and WSSV in wild shrimp in this area of the Western Hemisphere and to acquire specific pathogen free (SPF) L. vannamei for inclusion into the Oceanic Institute's genetic breeding program. The prevalence of the viruses was determined using the dot blot hybridization format, which is a commercially available molecular method for detecting these viruses. Dot blot hybridization assays can be used as an initial screening method to detect moderately to highly infected shrimp. The results from the dot blot assays indicated the prevalence of IHHNV in 28% and WSSV in 2% of the 104 hemolyrnph samples tested. Results from this study were used to establish the initial candidate SPF status of the animals that were assessed and to determine the prevalence of two serious pathogens of penaeid shrimp captured from the wild of the Pacific Ocean in the Central American region off the coast of Panama.  相似文献   

5.
Since early 1986, fatal cases of Pasteurella multocida infection following cat bites have been seen regularly among avian patients at our institute. The problems of the epizootiology of this infection are discussed on the basis of research during the last three and a half years. By evaluation of collected data from clinical examinations, autopsies, bacteriological and biochemical diagnosis of isolated strains from birds and cats the possibility of transmission via cat bite is discussed as well as the status of cats and birds in an epizootic chain. Even birds with trivial wounds caused by cats must be classified as emergency patients. The risk of an infection after a cat bite is about 56%. For treatment of a Pasteurella multocida infection Doxycycline should be used.  相似文献   

6.
臭氧冰对凡纳滨对虾保鲜效果的研究   总被引:5,自引:1,他引:4  
就采用高浓度臭氧冰对凡纳滨对虾(Litopeneaus vannamei)保鲜效果进行了探讨研究,结果表明,使用臭氧含量为5mg·kg^-1的臭氧冰时,具有显著的杀菌和抑菌作用,菌落总数减少91%,并降低了挥发性盐基氮的产生,可延长产品的保鲜期3~5d。臭氧冰具有杀菌力强,保鲜效果好,使用方便、快捷、环保,解决了臭氧不能保存和运输等技术问题,该研究解决长期以来依赖臭氧设备随产随用的被动结局,扩大了臭氧的应用范围,为水产品保藏提供一种新的保鲜方式。  相似文献   

7.
Biosecurity, as it is being applied to shrimp aquaculture, may be defined as the practice of exclusion of specific pathogens from cultured aquatic stocks in brood stock facilities, hatcheries, and farms, or from entire regions or countries for the purpose of disease prevention. To make a biosecurity program a functional concept in shrimp aquaculture, the relevant risks should be identified and the appropriate biosecurity measures put into practice to mitigate those risks. Examples of biosecurity measures put into place for this purpose may include such basics as site selection when the intent is to locate a new shrimp culture facility in an area where certain diseases are not enzootic. Standard facilitylfarm operating procedures can be adapted to minimize the risks of disease introduction and spread within a facility through such concepts as pretreatment of all source water, and reduced or “zero” water exchange. Stocking shrimp culture facilities with domesticated shrimp stocks that are free of specific diseases (“Specific Pathogen Free” or SPF) and or with stocks resistant to specific disease agents (SPR) is perhaps the most important single component of a biosecurity program. The example set by the development of domesticated SPF stocks of Litopenaeus vannamei has helped to make biosecure shrimp culture feasible. The development of these and other SPF stocks, and the diagnostic methods to develop and monitor them for specific diseases and disease causing agents, have been milestones in the development of the international shrimp farming industry in recent years, and it has contributed to the species rivaliig Penaeus monodon as the dominant farmed shrimp species. The regular monitoring (surveillance) of shrimp stocks in biosecure culture facilities is a necessary component of a biosecurity plan, as is having in place a contingency plan for disease containment and eradication should a breach occur in the physical and managerial components of a biosecure facility and a targeted disease occur.  相似文献   

8.
中国对虾几个产卵场群体携带白斑综合征病毒状况调查   总被引:5,自引:1,他引:4  
邓灯 《水产学报》2005,29(1):74-78
白斑综合征可以导致养殖对虾短时间内大面积死亡,是迄今为止对虾养殖业面临的最大挑战。本试验采用巢式PCR法对2001年采自黄渤海的中国对虾几个产卵场群体进行白斑综合征病毒检测,旨在较全面地了解黄渤海野生中国对虾携带病毒状况。各群体的阳性检出率分别为:朝鲜半岛南海岸群体55%;渤海湾群体35%;辽东湾群体94.7%;海州湾群体47.4%。结果显示,中国对虾几个产卵场群体均不同程度地携带白斑综合征病毒。辽东湾产卵场群体阳性检出率明显高于其他群体,推测人工孵化苗种放流、海湾的地理和水质条件与中国对虾的WSSV感染率相关。而中国对虾野生群体携带病毒对于对虾养殖业的影响是不容忽视的,笔者认为,只有从无特异病原(SPF)及抗特异病原(SPR)对虾养殖群体的建立着手才能从根本上避免由于对虾携带病毒而可能导致的病毒性疾病的暴发。同时,应该重视海区污染的治理,减少病毒病暴发的诱因。本试验建立了快速检测WSSV的PCR方法,1pg病毒核酸仍可检测到,为白斑综合征病毒病的防治及早期诊断提供了有效的手段。  相似文献   

9.
A method is described to introduce water-insoluble drugs into brine shrimp nauplii (BSN). The uptake of drug by brine shrimp may be modeled as a batch adsorption process; in this way, one can calculate the dosage required for a given population of BSN. The results of this study show that a drug can be loaded into BSN at concentrations up to 9 μg per nauplius. Such concentration is high enough to fulfill the recommended dosage for an adequate treatment of BSN-feeding fish or shrimp larvae. Results are also presented on the loss of drug upon the transfer of larvae from medicated water to drug-free water.  相似文献   

10.
11.
仿刺参幼体烂胃病及其致病原鉴定   总被引:14,自引:0,他引:14  
山东、辽宁两省在仿刺参(Apostichopus japonicus)苗种培育期间的5-7月,耳状幼体易发生一种以胃壁增厚、萎缩、溃烂为主要特征的“烂胃病”。从患烂胃病的耳状幼体中分离到1株细菌LW-1,人工回接感染实验证实其具有较强的致病性,并与自然发病症状相同。通过API半自动化鉴定和常规的生理生化试验的结果表明,LW-1具有弧菌属的特征,其表型特征与灿烂弧菌(Vibrio splendidus)相似。对该菌株16S rRNA基因序列分析和构建系统发生树。结果显示,菌株LW-1与灿烂弧菌的亲缘关系最近,相似率达到99.8%。菌株LW-1可鉴定为灿烂弧菌,并视为耳状幼体烂胃病的致病原之一。通过对多起仿刺参苗期烂胃病的调查研究表明,烂胃病病原也具有多样性和复杂性,并与投喂老化腐败的单胞藻饵料有关。  相似文献   

12.
1. In intensively operated dog breeding kennels bacterial infections are very significant in perinatal mortality. 2. Staph. aureus, Streptococci (type G) and also beta-haemolytic E. coli were transmitted intra-uterine or by the infected genital tract to the puppies. In many cases they are the cause of septicaemic death of the puppies. 3. A second important cause of infection is subclinical mastitis of the bitch, leading to septicaemic death of newborn puppies. 4. Prophylactic hygienic measures make possible a prognosis concerning the risk of perinatal death. This includes examinations of the dog and the bitch ante coitum, bacteriological examination of the genital tract of the bitch, and a bacteriological examination of the milk before the date of birth. 5. Prophylactic hygienic measures in combination with antibiotic treatment of the bitch or the puppies could reduce the losses of puppies to less than 10%.  相似文献   

13.
We investigated whether the positive impacts of artificial substrates on shrimp performance are altered in any way by their format or mode of fixation in the tanks. To examine this question, substrates were fixed vertically in the water column in three different configurations: SCF treatment (Substrate Completely Fixed), SPF treatment (Substrate Partially Fixed) and SFF (Substrate in Frond Format). Another treatment received no substrate and served as control (WS = Without Substrate). The shrimp were cultured for 38 days in intensive biofloc culture tanks at a stocking density of 1,125 shrimp m?3. In general, water quality variables were similar among treatments and remained within the appropriate range for shrimp culture. The final biomass was higher (8.5 kg m?3) and the feed conversion ratio (FCR) lower (1.6) in all tanks with substrates when compared with the WS treatment tanks (final biomass = 6.3 kg m?3 and FCR = 3.1). However, only shrimp from the SCF and SPF treatments had a higher survival rate (>95.0%) compared to those in WS tanks (75.9%), which was statistically similar to the SFF treatment (88.0%). These results show that substrate format and its mode of fixation in tanks can alter shrimp performance. In well‐aerated intensive tanks, substrates in frond format are constantly pushed to the tank surface, making it difficult for shrimp to adhere to the screens. In such situation, the extra surface provided by the substrates is not always available to the shrimp, a fact that minimizes the positive effects of substrate.  相似文献   

14.
15.
Dendronereis spp. (Peters) (Nereididae) is a common polychaete in shrimp ponds built on intertidal land and is natural food for shrimp in traditionally managed ponds in Indonesia. White spot syndrome virus (WSSV), an important viral pathogen of the shrimp, can replicate in this polychaete (Desrina et al. 2013); therefore, it is a potential propagative vector for virus transmission. The major aim of this study was to determine whether WSSV can be transmitted from naturally infected Dendronereis spp. to specific pathogen‐free (SPF) Pacific white shrimp Litopenaeus vannamei (Boone) through feeding. WSSV was detected in naturally infected Dendronereis spp. and Penaeus monodon Fabricius from a traditional shrimp pond, and the positive animals were used in the current experiment. WSSV‐infected Dendronereis spp. and P. monodon in a pond had a point prevalence of 90% and 80%, respectively, as measured by PCR. WSSV was detected in the head, gills, blood and mid‐body of Dendronereis spp. WSSV from naturally infected Dendronereis spp was transmitted to SPF L. vannamei and subsequently from this shrimp to new naïve‐SPF L. vannamei to cause transient infection. Our findings support the contention that Dendronereis spp, upon feeding, can be a source of WSSV infection of shrimp in ponds.  相似文献   

16.
本文介绍了用庆丰霉素防治草、青鱼粘细菌烂鳃病的试验结果。试验表明,防治草、青鱼烂鳃病,以采用投喂口服为宜。治疗药量为每100斤成鱼每天投喂庆丰霉素(固体)半斤(含250万单位),连投三天,有效率达96%;每100斤夏花鱼种,每天投喂1斤(含500万单位),连投4天,有效率为72.7%。预防的投药方式和治疗剂量相同,唯应在该病流行季节之前投喂,夏花鱼种以连投7天为宜。试验表明,成鱼投药组死亡率为1.7%,对照组死亡率达27%;夏花鱼种投药组死亡率为15.7%,对照组死亡率为40.3%。  相似文献   

17.
A poxvirus infection in a cat and its owner is recorded. The clinical course of the disease as well as the pathological and the histopathological changes are described. The diagnosis "poxvirus infection" was confirmed by electronmicroscopy and cell culture techniques. This is the first human poxvirus infection in the Federal Republic of Germany in which the source of infection was found to be an infected cat. The serological investigation of 104 cat sera revealed antibody titres in 14 cases, indicating that poxvirus infections in cats are not isolated cases.  相似文献   

18.
The growth response to supplementation of mixed diets with a protein extracted from frozen squid (squid protein fraction: SPF) was tested at levels of 1.5, 3.0, 6.0 and 16.0% in the diet in four species of shrimp: Penaeus stylirostris, P. vannamei, P. monodon and P. indicus. In P. stylirostris and P. vannamei , growth rates were significantly improved by SPF even at the lowest level of supplementation. Improvement was obtained only with 6 and 16 percent in P. monodon , while no significant response was observed in P. indicus. The growth promoting effect of SPF at 16% of the diet could be explained by its nutritional value, particularly by its amino acid content, although all diets were supposed to be well balanced in all known nutrients. However, at lower levels the results obtained seemed to be due to the unknown growth factor (UGF) already mentioned in previous reports.  相似文献   

19.
Different measures of capacity and capacity utilization (CU) are estimated and examined for the multi-species Danish Gill-net fleet using a mathematical programming approach—data envelopment analysis (DEA). The potential capacity output is calculated using an output-orientated measure. CU is assessed using both a partial CU measure, which permits CU to be assessed relative to each output, and a ray measure. Based on the ray measure, the average CU for the Danish Gill-net fleet was estimated to be between 0.85 and 0.95. The partial CU measure for cod was determined to be approximately the same as the overall or ray CU measure, but the partial CU measure for plaice was less than the level of the ray measure, which indicated that the production of plaice could be increased by a higher proportion than could the production of cod. The optimal variable input utilization was also estimated. It was determined that, on average, the variable input—number of trips—could be increased by 27% compared to the optimal level. Results also indicated higher excess capacity for cod and sole than for other species, which is in accordance with how the fishery developed.  相似文献   

20.
IHB系稀有鮈鲫遗传结构研究   总被引:1,自引:0,他引:1  
分析IHB系稀有鮈鲫在繁育过程中的遗传结构变化,旨在鉴定IHB系的遗传质量,为实验动物封闭群的建群和维持以及濒危物种种群保护提供参考和借鉴。IHB系稀有鮈鲫建群原代(P0)为2006年采自四川省汉源县的野生个体,采用最佳避免近交法繁育出F1~F8世代,利用12对微卫星位点对遗传结构进行分析。在IHB系培育过程中,平均观测等位基因数从4.4个降低为4.1个,平均有效等位基因数从4.0个降低为3.0个,平均期望杂合度从0.5878降低到0.5518,平均多态信息含量从0.5509降到0.5293;随着传代的持续,后代与建群原代之间的遗传距离与分化程度有逐渐增大趋势,但相邻世代间的差异逐渐减小;繁育过程中共丢失了6个等位基因,从F5代后所有等位基因频率均无显著变化。经过8代的繁育,IHB系遗传多样性虽略有下降,但仍维持适宜的水平,近交程度得到有效控制,且遗传结构趋于稳定,符合实验动物封闭群遗传质量要求。IHB系可作为稀有鮈鲫地模种群的活体基因库。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号