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1.
Clinical bovine mastitis in Norway   总被引:1,自引:0,他引:1  
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2.
The larvae of the sloth moth, Cryptoses choloepi, live in the dung of the three-toed sloth, Bradypus infuscatus. Adult female moths apparently leave the fur of the sloth to oviposit when the sloth descends, once a week, to the forest floor to defecate. Newly emerged moths fly from the dung pile into the forest canopy to find a sloth.  相似文献   
3.
农药亚致死剂量对优姬蜂交配行为影响的研究   总被引:5,自引:0,他引:5  
用100×10-6%农梦特和空白农梦特乳油,以及0.01×1O-6%氯氰菊酯处理寄生于小菜蛾幼虫的优姬蜂雄蜂,观察农药亚致死剂量对优姬蜂交配行为的影响。结果表明,受农梦特处理的雄蜂只有68.18%在遇到雌蜂时引起翅膀扇动。在农梦特和氯氰菊酯处理中,雄蜂对雌蜂在交配行为上的反应迟钝,它们从试验开始到扇动翅膀的时间显著地比对照和空白农梦特乳油的推迟,其交配率分别为27.27%和55%,交配抑制率分别为53.68%和32.06%。  相似文献   
4.
The male of Calopteryx maculata (Beauvois) (Odonata) uses its penis not only to transfer sperm to the female but also to remove sperm deposited in the female's sperm storage organs from previous matings. Apparently, no such sperm removal function has previously been attributed to the intromittent organ of any animal.  相似文献   
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Tansy (Tanacetum vulgare L.) was cultivated at the Norwegian Crop Research Institute at the Apelsvoll Research Centre, Division Kise, in the period from 2000 to 2001. The study focused on different harvesting regimens for high biomass production and essential oil (EO) yield and quality. Two tansy genotypes from Canada (Richters and Goldsticks) and three Norwegian genotypes (Steinvikholmen, Alvdal, and Brumunddal) were studied. The Canadian genotypes reached a height of 130-145 cm and showed a higher dry weight of aerial plant parts compared to the Norwegian plants in 2000. Similar oil yields could be observed for the Canadian types and genotype Steinvikholmen in the range of 30.8-34.6 L/ha when the plants were harvested twice during budding and before flowering after regrowth (year 2001). In contrast, single harvesting at the full bloom stage resulted in higher oil yields, between 42.1 and 44.5 L/ha (Canadian genotypes), whereas 21.0-38.4 L/ha was obtained from the Norwegian types. Tansy genotypes could be grouped into the following chemotypes: the mixed chemotypes Steinvikholmen (thujone-camphor), Alvdal (thujone-camphor-borneol), Goldsticks (thujone-camphor-chrysanthenyl type), and Brumunddal (thujone-camphor-1,8-cineole-bornyl acetate/borneol-alpha-terpineol) and the distinct chemotype Richters, with average concentrations of (E)-chrysanthenyl acetate >40% in both leaf and flower EO.  相似文献   
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A total of 855 pig lungs were collected at slaughter and evaluated macroscopically. Bacteriological examinations were carried out on tissue samples from chronic pleuropneumonic lesions (n = 196) and from chronic bronchopneumonic lesions with suppuration (n = 14). Samples from normal lung tissue (n = 22) were also included. Pasteurella multocida was isolated from 54%, Actinobacillus (Haemophilus) pleuropneumoniae from 11%, and Streptococcus spp. from 14% of the pneumonic lesions, respectively. From normal lung tissue P. multocida was isolated from 3 (14%) of the samples, A. pleuropneumoniae was not recovered and streptococci were isolated from only 1 (5%) of these samples. The above mentioned bacterial species were recovered either in pure cultures or mixed with various other microbes. A total of 109 P. multocida strains were further characterized by capsular serotyping and testing for production of dermonecrotic toxin. Ninety-nine (91%) of the strains were capsular type A 10 (9%) were type D. Out of the type A and the type D strains 94% and 90% were toxigenic, respectively. Most of the A. pleuropneumoniae strains were serotype 2. Strains of serotypes 1 and 7 were also identified. The majority of the streptococci were identified as either Streptococcus suis or Streptococcus dysgalactiae. Actinomyces pyogenes was isolated from 14% of the lesions and anaerobic bacteria from 18%, respectively. The significance of the various bacterial species in relation to the development of chronic pneumonic lesions is discussed. Special attention is paid to P. multocida, and it is concluded that this bacterial species is probably of importance for the development of both types of chronic pneumonias.  相似文献   
9.
Three hundred and eighty-four Staphylococcus aureus isolates obtained from mammary secretions from 332 ewes kept for meat production were typed by pulsed-field gel electrophoresis (PFGE). The ewes were from 242 flocks located in 13 counties distributed in four regions of Norway. In total, 64 different pulsotypes were identified, 31 of these were represented by a single isolate. Fifty-nine percent of the isolates belonged to one of five closely related pulsotypes. This group of pulsotypes occurred in all the counties. Although widely disseminated, the proportions of the prevalent and closely related pulsotypes differed between the regions. Nine pulsotypes were unique to single regions but the number of isolates belonging to each of these pulsotypes was low. Resistance to penicillin was found in only 3 of the 384 S. aureus isolates. These represented three different single banding patterns, not related to any of the prevalent pulsotypes found.  相似文献   
10.
The serum activity of aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), creatine kinase (CK), and gamma-glutamyltransferase (GGT) was determined at the time of first and subsequent treatments in milk fever cows which responded differently to treatment, and in a number of healthy, periparturient cows. Serum ASAT, ALAT and CK levels were lower in the healthy cows than in the milk fever cows at first treatment. Serum ASAT and serum CK were, at first treatment, higher in the milk fever cows which did not recover than in those which recovered. At second and subsequent treatments, serum ASAT and serum ALAT were higher in the cows which failed to recover, and these cows also showed the highest levels of serum CK up-to and including fourth treatment. After an overall assessment of serum activity of the various enzymes, it is concluded that muscle damage was a significant complication both in cows which recovered and in those which failed to recover, while liver damage was of little importance.  相似文献   
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