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Values of selected parameters of milt from carp, Cyprinus carpio L., representing four breeding strains - the Lithuanian strain B (n = 12); the Hungarian strain W (n = 16), the Ukrainian strain Ur (n = 16), and the Polish strain 6 (n = 14) collected during the spawning season after stimulation with Ovopel (1 pellet/kg) were compared. Spermatozoa motility (%), their concentration in milt (billion/ml), total protein content in seminal plasma (mg/ml), as well as its osmolality (mOsm/kg) were determined. The activity of lactate dehydrogenase (LDH), acid phosphatase, and anti-proteolytic activity (APA) were also determined. Values obtained for the activity of the analyzed enzymes are presented in U/I. Significant differences were observed among the basic parameters of milt only in total protein content between males of the Ur and W strains (P < 0.01) and strain 6 (P < 0.05). Significant differences were not noted in the activity of LDH, AcP, or APA(P>0.05). High correlation coefficients (R = 0.862, P < 0.001 and R = 0.667, P < 0.01) between APA activity and total protein content in the seminal plasma of males from strain 6 suggest that protective proteins might constitute the main protein fraction in the seminal plasma of these fish.
This paper deals with fish sperm cryopreservation techniques emphasizing the contribution of Polish science in this field in the past decade. Useful aspects of this biotechnology both in commercial applications for fish hatcheries, as well as in the protection of endangered species, are presented. Stages of the cryopreservation procedure are described together with aspects of sperm collection and spermatozoa physiology of freshwater euteleosts and sturgeons. Details of sperm quality evaluation and their purpose in sperm deep freezing are discussed. Design criteria concerning choice of diluents and cryoprotectants as well as dilution ratios and storage methods are described. The use of thawed sperm for ova fertilization together with thawing conditions and procedures with regards to the storage method are explained. Prospects for biochemical methods of sperm quality evaluation, especially emphasizing their usefulness in predicting the effects of fish sperm freezing/thawing procedures are also introduced.
The aim of the study was to adapt a method to determine acrosin activity of human spermatozoa to arctic fox (Alopex lagopus L.) spermatozoa. We modified this method by reducing sperm count per sample from 1÷10 × 106 to 25÷200 × 103, incubation time from 180 minutes to 60 minutes, and Triton X-100 concentration in the reaction mixture from 0.01% to 0.005% per 100 cm3. It has also confirmed that arctic fox seminal plasma is rich in proteinases and their inhibitors. To completely abolish the inhibitory effect of seminal plasma on acrosin activity it is recommended to wash the spermatozoa four times. Benzamidine served an inhibitor of acrosin activity.
В результате комплексных биохимических исследований семени хряка разработали оригинальный метод замораживания семени („картовский” метод). Представили подробное описание технологической процедуры для замораживания полного эякулята или живчиковой фракции с применением техники замораживания в тубах или шариках. Полученные качественные показатели семени по разморожении (подвижность живчиков ок. 30%, процент живчиков с нормальным акросомом ок. 50%, выживаемость в 37°С 180—360 мин.), как и биологическая ценность семени (показатель супоросности ок. 45%, число живорожденных поросят в приплоде ок. 7,0) не отклоняются от результатов, представленных авторами различных технологий замораживания семени хряка. Метод может использоваться для селекционных работ в пределах вида.
Acid phosphatase (AcP) is a commonly observed enzyme in animal semen. In this study, AcP in rainbow trout (Oncorhynchus mykiss) spermatozoa was partly purified and characterized. Extraction in 0.85% NaCl with 0.1% Triton X-100 enabled obtaining 95% of total AcP activity observed in sperm supernatant. Kinetic characteristics were described for the enzyme from sperm extract and for the partly purified enzyme following gel filtration. The optimum pH was 5.8 for unpurified and 5.6 for partly purified enzyme. The affinity of the substrates measured in the sperm extract for p-nitrophenylphosphate dissodium salt and b-glycerophosphate was Km = 1.5 × 10-3M and Km = 1.9 × 10-3M, respectively. The Km for partly purified enzyme was similar at 1.67 × 10-3M measured with p-nitrophenylphosphate dissodium salt. L-tartaric acid and ammonium molybdate were the inhibitors of AcP for unpurified and partly purified enzyme. SDS-PAGE electrophoresis revealed that AcP from rainbow trout had a molecular weight of about 41 kDa.
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