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11.
Lemon balm (Melissa officinalis L.) is used since ancient times because of its sedative, spasmolytic and antiviral effects. Its therapeutic impact is due to the content of essential oil and rosmarinic acid. A set of 68 M. officinalis genotypes was evaluated for content and composition of essential oil and the content of rosmarinic acid. For all genotypes the level of ploidy was determined. The 68 genotypes were clone plants grown and evaluated for two years at Quedlinburg. For analysis of secondary metabolites distillation, gas chromatography and high performance liquid chromatography was used. The content of essential oil varied in this study in ranges from 0.03 to 0.33% for the second cut 2010 and 0.01–0.35% for the second cut 2011. The rosmarinic acid content ranged in the year 2010 from 3.67 to 7.55% and in the year 2011 from 4.92 to 8.07%. Via statistical analyses two chemotypes of essential oil were found: chemotype citral and chemotype β-caryophyllene oxide. Ploidy was determined for all genotypes and two cytotypes were found: diploid 2n = 2x = 32 (62 of 68 genotypes) and triploid 2n = 3x = 48 (6 of 68 genotypes).  相似文献   
12.
The authors of this paper have produced live vaccine to cope with infectious agalactia in goat. The vaccine (culture) was used on 360, 924 goats kept on ajmaks in Bajanchongor and Gobi-Altaj, in 1986. The number of pathologically affected goats went down by a factor of 4.5, as compared to 1985. Mortality was reduced to one third. Abortions declined by a factor of 2.6 and infertility among goats by 1.6. The conclusion is that sheep of the Mongolian breed are not susceptible to infectious agalactia. Large-scale production tests of live cultures supported hopes for successful action on this infectious disease under Mongolian conditions.  相似文献   
13.
Inhalt Es Wurde versucht, 276 Ejakulate von 50 Bullen der Rasse Deutsche. Fleckvich mit Hilfe eines einfachen Objekträgertestes ohne die im Ruutineverfahren üblichen Maβnahmen (Adaption, Einfrieren) auf ihre Gefriertauglichkeit zu testen. Dies erfolgte durch einen Vergleich der Auftauraten von verdünnten Spermaproben gleich nach dem Tiefgefrieren ohne Adaption auf Objektträgern und von solchen die nach 6–8stündigcr Adaption routinemäβig in Ampullen bzw. Pailletten eingefroren wurden. Die Untersuchungen führten zu folgenden Ergebnissen: 1. Die Auftaurate von Spermaproben, die ohne Adaption auf Objektträgern im Stickstoffdampf eingefroren wurden, lassen bis zu einem gewissen Grade eine Vorausbestimmung des Einfrierergebnisses und damit der Tiefgefriertauglichkeit eines Ejakulates zu. Bullen, deren Sperma im Objektträgertest ein Auftaurate von über 20% zeigt, werden als gefriertauglich, jene mit einer Spermienmotilität nach dem Auftauen der Objektträgerproben von unter 5% als gefrieruntauglich und solche, deren aufgetautes Sperma 5% bis 20 % motile Spermien aufweisen, als bedingt tauglich angesprochen. 2. Zur Beurteilung eines Bullen hinsichtliclz der Gefriertauglichkeit seines Spermas reicht die Testung von 3 Ejakulaten aus. 3. Der Objektträgertest ist leicht durchführbar und zeitsparend. Er ist für die Auswahl der Bullen hinsichtlich der Gefriertauglichkeit ihres Spermas für die Praxis allerdings nur bedingt einsatzfähig, da ein groβer Teil der Stiere doch noch routinemäβig nachgetestet werden muβ. Er bringt eindeutige Ergebnisse nur dann, wenn die Auftaurate höchstens 5% und deutlich mehr als 20 % beträgt. Contents (The determination of the suitability for deep freezing of bull semen using a slide test) . 276 ejaculates from 50 bulls of ther German Fleckvieh breed were studied for deep freezing suitability using a simple slide test without the routinely used mea.rures (adaptation, freezing). A comparison was made of the thawing rates of diluted semen samples immediately after deep-freezing without adaptation on slides and after 6–8 hours adaptntion in ampoules or paillettes. The following results were obtained: 1. The thawing rate of semen samples frozen without adaptation on slides in the vapour phase of nitrogen allow a certain degree of predetermination of the freezing result and therefore of the suitability of an ejaculate for deep freezing. Bulls whose semen shows a thawing rate of over 20% by the slide test are taken as being suitable for freezing; those with a sperm motility after the slide test of less than 5% are unsuitable; those with a sperm motility of 5–20% are considered as conditionally suitable. 2. 3 ejaculates are sufficient to test a bull for suitability of semen for deep-freezing. 3. The slide test is easy to carry out and saves time. However, for the selection of bulls on the basis of deep freezing of semen in practice it is limited, since a large proportion of bulls still have to be tested further. The test only gives unequivocal results if the thawing rate is less than 5% or more than 20%.  相似文献   
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There appears to be a lack of information concerning responses of mules to natural infection or experimental inoculation with equine infectious anemia virus (EIAV). In the present study EIAV was isolated from mules, for the first time, and its pathogenicity in naturally infected and experimentally inoculated animals was investigated. Two naturally infected (A and B) and three EIAV free mules (C, D and E) were used for this purpose. Mule A developed clinical signs, whereas mule B remained asymptomatic until the end of the study. Mules C and D were each inoculated with 10ml of blood from mule A and developed signs of the disease; they were euthanatized or died at day 22 and 25 post-inoculation, respectively. Mule E served as a negative control. The virus was isolated from the plasma samples of mules with clinical signs of the disease (A, C and D), but not from the asymptomatic mule B. Both proviral DNA and viral RNA were amplified from blood and tissues of the infected animals by nested polymerase chain reaction (nPCR). Antibodies were not detected in the two experimentally infected mules until their natural death or euthanasia. Clinicopathological and laboratory findings showed that, in mules, EIAV produced clinical signs similar to those observed in horses and ponies. Nested PCR proved to be a rapid, sensitive and specific diagnostic method for the detection of EIAV, regardless of the disease stage.  相似文献   
17.
A 4-year (1996–99) survey of the biology of L. serricorne (F) (Coleoptera, Anobiidae) on stored tobacco has taken place in Thessaloniki, northern Greece. For the trapping of the adults, pheromone ('New Serrico' and 'Black Stripe Moth') as well as electric (black light) traps were used. The first generation adults emerging from larvae hibernating inside the tobacco bales appeared flying on the 17/5, 16/5, 28/4, and 30/4 of the years 1996, 1997, 1998, and 1999, respectively. In parallel observations, adults inside the bales were found on the 14/5, 12/5, 23/4, and 26/4 of the above-mentioned years, respectively. Termination of flights, in all the years concerned, took place during October or November, while the last flights of November were recorded in temperatures of about 13°C.  相似文献   
18.
Hydroponically grown cucumber (Cucumis sativus) seedlings were inoculated with zoospores of 1 mycoparasitic (Pythium oligandrum) and 2 pathogenic (Pythium aphanidermatum and Pythium group F) Pythium spp. During the first 2 days after inoculation, all the Pythium spp. caused reduction in the root length. However, roots treated with Pythium oligandrum quickly reached the length of the control and on the 8th day, and for the rest of the experimental period, stimulation of root elongation was noted. Pythium oligandrum was not pathogenic on cucumber and no differences in the fresh weights of control and Pythium oligandrum inoculated plants were observed in the course of the experiment. Pythium group F and Pythium aphanidermatum were pathogenic on cucumber seedlings, but their pathogenicities differed. Thus, while Pythium group F had a constant, negative influence on root length and plant growth, measured as fresh weight, Pythium aphanidermatum caused generalized necroses of the root system, inhibiting consistently root elongation and plant growth and finally causing plant death. Moreover, the zoospores of 2 mycoparasitic species, Pythium oligandrum and Pythium periplocum, were not attracted to roots of cucumber and accumulated on the roots in very low numbers compared to those of the pathogenic species, Pythium aphanidermatum, which were strongly attracted and accumulated in large numbers. Finally, it was also found that Pythium oligandrum colonized the roots very poorly, while Pythium group F and Pythium aphanidermatum were significantly better root colonizers. The significance of these findings is discussed in relation to the ecology of Pythium species and biocontrol.  相似文献   
19.
Ultrasonography was used to compare adhesions induced by two different methods of gastropexy in 16 dogs. An incisional gastropexy technique was used in eight dogs (group 1) and a 'modified' gastropexy technique in the remaining eight (group 2). The length and thickness of the gastropexy and the peristaltic activity of the stomach were measured ultrasonographically and compared between groups. Measurements for the two groups were taken in the early postoperative interval (two to four days), intermediate postoperative interval (eight to 20 days) and late postoperative interval (57 to 79 days). Both techniques were equally successful in forming permanent adhesions at two months postoperatively and there was no recurrence of gastric dilatation and volvulus. The length and thickness of the gastropexy were similar for both groups at two months postoperatively and there were no surgical complications with either technique. The modified gastropexy provides a technique that can easily be performed by a single surgeon , with no increased operative time or duration of anaesthesia, and with the formation of a permanent adhesion.  相似文献   
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