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1.
Inhalt: An 81 Versuchs- und 92 Kontrolltieren der Rasse “Potnische Schwarzbunte” aus 3 Problembetrieben wurde ein Versuch zur Sterilitätsprophylaxe rnit der PRID-Spirale durchgeführt. Anhand klinischer Befunde und Milchprogesteronwerten wurde die Untergruppe aus Kühen mit Ovardystrophie (18 Versuchs- und 22 Kontrolltiere) gebildet und extra ausgewertet. Der Behandlungsbeginn lag zwischen 60 und 80 Tage post partum. Die Versuchstiere wurden mit der PRID-Spirale 12 Tage lang behandelt, die Kontrolltiere erhielten Injcktionen rnit Kochsalzlösung und solche rnit Ovardystrophie wurden zusätzlich mit einer Eierstocksmassage behandelt. Die Versuchstiere wurden 56 und 72 Stunden nach Entfernung der Spirale blind besamt. Die Brunstin-duktionsrate betrug insgesamt 90,1%, bei denen rnit Ovardystrophie 77,7%. Die An-wendung der PRID-Spirale führte zur Verbesserung der Fertilitätslage. Die Gesamt-trächtigkeitsrate lag mit 87,6% bei den Versuchskühenüber derjenigen der Kontrollkü-he mit 79,3%. Die Behandlung der Tiere rnit Ovardystrophie erbrachte eine Gesamt-trächtigkeitsrate von 88,8% bei den Versuchs- und 72,7% bei den Kontrolltieren. Die Zwischentragezeit betrug bei den Versuchstieren 101,2 Tage und bei den Kontrolltieren 113,3 Tage (p ≤ 0,05). Bei den azyklischen Tieren lag die Zwischentragezeit bei 104,6 Tage bzw. 134,7 Tage (p ≤ 0,05). In einem anderen Versuch wurde 20 Hybriden zwischen Wisent und Hausrind rwecks Zyklussynchronisation die PRID-Spirale verabreicht. Die Brunstinduktionsrate betrug 66,6%, das Erstbesamungsergebnis nach Doppelbesamung 30%, die Gesamtträchtig-keitsrate nach dem Decken der umrindernden Kreuzungstiere rnit einem Bullen 90%. Die Deckperiode konnte verkürzt werden. Contents: Investigations on the synchronization of estrus cycle in cattle from farms with fertility problems and in cross-breeds between bison and cattle with a PRID-de-vice In 81 experimental and 92 control animals of the “Polish Black and White” breed derived from 3 farms with fertility problems an investigation was carried out for sterility prophylaxis using the PRID-device. Based on clinical findings and milk progesterone values cattle with ovarian dystrophy (18 experimental and 22 control animals) from a special group were used. The begin of treatment was between 60 and 80 days post partum. All experimental animals had received a PRID-device for a duration of 12 days. Control animals were injected with physiological saline solution and animals with ovarian dystrophy were treated additionally with ovarian massage. Experimental animals were inseminated 56 and 72 hrs after removal of the device. All animals taken, estrus was induced in 90.1% of the animals, while only 77.7% of animals with ovarian dystrophy came to estrus. Application of the PRID-device led to an improvement of fertility. Pregnancy rates in experimental animals were 87.6%, while only 79.3% of the control animals were pregnant. Treatment of animals with ovarian dystrophy resulted in 88.8% pregnancies for treated and 72.7% for control animals. Experimental animals were non-pregnant for a duration of 101.2 days, while control animals remained non-pregnant for 113.3 days (p < 0.05). Acyclic cattle had a non-pregnant period of 104.6 days and 134.7 days (p < 0.05) respectively. In a second experiment 20 cross-breeds between bison and domestic cattle were treated with a PRID-device for synchronization of the estrus cycle. The rate of estrus induction was 66.6%, the fertility after double insemination 30%, the total pregnancy rate improved after mating with a bull of animals that had not conceived to 90%.  相似文献   
2.
A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the 'HNR' genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity ('LNR' genotypes) when an extra dose (40 kg N ha−1) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both 'HNR' and 'LNR' genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha−1) at the time of anthesis increased grain yield of 'HNR' genotypes by 38.5 % as compared to 'LNR' genotypes.  相似文献   
3.
The state of mucus synthesis in the goblet cells of the small intestine was studied in conventional piglets infected with a dose of 200,000 oocytes of the coccidium Isospora suis the first and fifth day after parturition. The synthesis of mucus and its chemical characteristics undergo significant changes during the third and fourth day after infection. The activity of acid and neutral mucous substances declines; their level and the physiological synthetic function of goblet cells begin to return to the normal during the period starting on the eight to tenth day after infection. However, there were no fully functioning goblet cells in the broken numerical ratio even at the end of the period of investigation, i.e. the 13th day after infection. The thin surface layer of mucus remained almost unchanged within the whole extent of the small intestine parts studied.  相似文献   
4.
5.
The effects of 0.5%, 0.3% and 0.1% w/w concentrations of Senna occidentalis (So) seed mixed with commercial ration were studied in 18 groups of 32 broiler chicks each, from 1 day to 49 days of age. Three groups were fed one of the rations throughout their lives (TL). Three other groups were fed one of the rations from the 1st to the 28th day of life (starter phase, SP), and the final 3 groups were fed one of the rations from the 29th to 49th day (finisher phase, FP). Each experimental group was matched by a control group fed the same diet over the same period but without the inclusion of So. All the animals were killed at 49 days of age, and blood was collected from 10 birds in each group for biochemical studies (ALT, AST, GGT, LDH, UA). A complete necropsy was performed on 3 birds from each group. No significant differences in the biochemical parameters in the serum were found between the control and experimental chicks, but animals treated with 0.5% So in groups FP and TL, gained less weight and chicks that received 0.3% So or 0.5% So in the ration throughout life (TL) had a larger feed conversion ratio. Besides this, degenerative changes were found in the striated skeletal muscle in the chest, in the myocardium and in the liver in the animals that received the higher concentrations of So seeds.  相似文献   
6.
7.
This study was conducted to evaluate the effects of dietary thiamin on the physiological status of the juvenile grouper, Epinephelus coioides. Graded levels of thiamin (0.08, 0.50, 2.12, 3.15, 4.63, 12.37 mg thiamin kg−1 diet) were fed to grouper juveniles (mean weight: 16.97 ± 0.14 g) for 10 weeks. Although fish fed the thiamin-deficient (TD) diet showed no obvious symptoms of thiamin deficiency or increased mortality, those fed the lowest doses of thiamin (0.08 and 0.50 mg thiamin kg−1 diet) had significantly decreased transketolase activity in the liver. In addition, the level of liver thiobarbituric acid reactive substances in fish fed the TD diet was 33–67% higher than that in fish with the thiamin-supplemented diet. There were no significant differences in superoxide dismutase activity between the different groups of fish.  相似文献   
8.
  总被引:6,自引:0,他引:6  
The 2.0 angstroms crystal structure of a complex containing bee-venom phospholipase A2 (PLA2) and a phosphonate transition-state analogue was solved by multiple isomorphous replacement. The electron-density map is sufficiently detailed to visualize the proximal sugars of the enzyme's N-linked carbohydrate and a single molecule of the transition-state analogue bound ot its active center. Although bee-venom PLA2 does not belong to the large homologous Class I/II family that encompasses most other well-studied PLA2s, there is segmental sequence similarity and conservation of many functional substructures. Comparison of the bee-venom enzyme with other phospholipase structures provides compelling evidence for a common catalytic mechanism.  相似文献   
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10.
A model reaction system was developed for generating pure thiosulfinates and propanethial-S-oxide (PTSO) using an isolated alliinase (EC 4.4.1.4) and isolated or synthetic alk(en)yl-L-cysteine sulfoxides (ACSO). Reaction yields ranged from 30 to 60% after 3 h at 21-23 degrees C, and organosulfur reaction products were extracted into CHCl3 to yield product preparations of controlled composition. A pure thiosulfinate or PTSO was derived from a single ACSO, and a preparation containing a mixture of four thiosulfinate species was derived from reaction mixtures employing binary ACSO substrate systems. Identities of homologous thiosulfinates and PTSO were confirmed by 1H NMR. This approach has the potential to be used as a preparative tool for yielding pure thiosulfinates and PTSO to facilitate the study of chemical and biological properties of this group of compounds or as a means to study the dynamics of organosulfur chemistry in preparations from Allium spp.  相似文献   
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