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Internal organs of 74 racoon dogs originating from the eastern districts of the Federal Land Brandenburg were subjected to a complete helminthological dissection. In addition, samples of diaphragma muscles from 46 further animals were examined for Trichinella larvae. Altogether 3 trematode- (Alaria alata, Isthmiophora melis, Metorchis bilis), 3 cestode- (Mesocestoides sp., Echinococcus multilocularis, Taenia polyacantha) and 7 nematode species (Capillaria aerophila, C. plica, Trichinella spiralis, Uncinaria stenocephala, Molineus patens, Crenosoma vulpis, Toxocara canis) could be identified. Thereby, the racoon dog has a comparable helminth spectrum as well known in red foxes. Differences in the frequency of the occurrence of helminths in both hosts can be explained by different food preferences.  相似文献   
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To optimise spring vaccination campaigns the following set of data has been analysed; (i) population dynamics of the red fox, (ii) onset and progress of the reproductive season, and (iii) maternal immunity and the immune response of fox cubs to oral vaccination. The field data originated from foxes caught in Bavaria, Germany. The results of our analysis clearly demonstrate that certain periods during spring are less suitable for bait distribution. If the objective of a vaccination campaign is to reach only the adult foxes, it is suggested to conduct the campaign during the first half of March. If also young foxes are to be vaccinated, baits should not be distributed before the end of May in previously baited areas, because a large segment of the young fox population can not be vaccinated effectively before this date as a result of maternally transferred immunity. In areas vaccinated for the first time, baits can be distributed earlier, since 5 weeks old cubs are already immunocompetent.  相似文献   
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Studies on the immunogenicity and efficacy of SAD B19 attenuated rabies virus vaccine in foxes under laboratory conditions were conducted. Twenty-seven foxes (Vulpes vulpes) were offered a vaccine bait containing 10(6.3) FFU/ml SAD B19. Blood samples were collected 60, 110 and 190 days post-vaccination. On day 190 post vaccination the animals and 14 controls were challenged with a canid street rabies virus. Twenty-four of the 26 vaccinated foxes (92.3%) survived the challenge, whereas all the controls died from rabies. The two vaccinated foxes that did not survive the challenge did not show any detectable level of rabies neutralizing antibodies at any time after vaccination. The geometric mean titres (GMT) of foxes that seroconverted after vaccination were 43.5, 33.9 and 43.5 IU/ml 60, 110 and 190 days post-vaccination, respectively. Furthermore, to test the vaccine virus under sub-optimal conditions five naive and nine previously vaccinated vixens received 2 ml SAD B19 (10(6.7) FFU/ml) by direct administration of the vaccine virus into the oral cavity shortly before or during pregnancy. All vixens seroconverted above the threshold of 0.5 IU/ml. No booster effect was observed in the immune response of the previously vaccinated animals.  相似文献   
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用本实验室分离鉴定的致病性牦牛大肠埃希氏菌,按常规方法制备了4批氢氧化铝胶灭活疫苗。对牦牛大肠埃希氏菌的菌液培养、纯粹检验、活菌计数、灭活等进行了探索,并对用该菌研制成的疫苗进行了常规检验。结果4批灭活疫苗经无菌检验为阴性;经物理性状检验为:静置后上层是淡黄色的澄明液体,下层为灰白色沉淀,振荡后呈均匀混浊液;经牦牛安全检验结果为安全;经牦牛效力试验有效。牦牛大肠埃希氏菌病灭活疫苗为免疫预防该病打下了良好的基础。  相似文献   
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本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化  相似文献   
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The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ≥3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (≥30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (≤15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI‐MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P‐38:5) + H]+ and/or [PC (P‐36:2) + Na]+, [PC (38:2) + H]+, [PC (38:5) + Na]+ and [TAG (60:8) + NH4]+ were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development.  相似文献   
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