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Constanţa, Romania

Anghel A.,Ovidius University | Zamfirescu S.,Ovidius University | Sogorescu E.,Ovidius University | Rotaru M.,Ovidius University | And 2 more authors.
Annals of the Romanian Society for Cell Biology | Year: 2012

The photoperiod is the primary environmental used to regulate reproduction on bucks. The objective of scientifically research was to observe the variations of testosterone concentration in correlation with testicular volume for a period during 2 years, at White of Banat bucks. The studies were conducted at the experimental farm of ANCC Caprirom and the biochemical determinations of testosterone concentrations were realized at the Ovidius University - Laboratory of Cellular and Molecular Biology by ELISA method. Plasma testosterone was analyzed in blood samples collected once a week. Blood samples were collected always at the same time of the day to avoid circadian variations. The testosterone concentrations on White of Banat between January and February for the first and second year of experiment were over than basal level and in March the testosterone level decreases down to the basal level. On the end of spring, in both years of experiment, we observed a slight augmentation of the testosterone level. The testosterone concentrations were increased at the beginning of summer and after than followed by a slight decline of this concentration in July and increase in August. In September, the concentration of testosterone was highest comparative with values of the testosterone level for the entire year. In the last two months of autumn, the testosterone concentrations decreased comparative with results obtained in September. On December the testosterone level on experimentally bucks begins to increase for the first year of the study.

Sogorescu E.,Ovidius University | Zamfirescu S.,Ovidius University | Anghel A.H.,Icdcoc Palas | Nadolu D.,Icdcoc Palas | Dobrin N.,Ovidius University
Annals of the Romanian Society for Cell Biology | Year: 2012

Photoperiod is a major environmental factor of regulation of testosterone secretion testicular volume and sperm production. The studies were conducted on the experimental farm of Caprirom and the biochemical determinations of testosterone were realized at Ovidius University-Laboratory of Cellular and Molecular Biology, Constanta, Romania. The experiment started on 15/12/2010 to 26/05/2011. The bucks of the control group (n=10) remained in a open shed under natural daylength and ambient temperature throughout the experiment. Experimental groups (n=10) were placed in light-proof sheds and were exposed to alternations of 3 months of long days (LD: 16 h of light/day; lights-on: 06:00 h, lights-off: 22:00 h) and 3 months of natural photoperiod. The photoperiodic treatment started on December 15th 2010 to March 15th 2011 for experimental groups. In room, light was provided by 4 fluorescent tubes giving a light intensity of 300 lx measured laterally to the eyes of the animals. Changes in sexual activity of males were studied on the experiment in order to evaluate the efficiency of photoperiodic treatments. In light-treated groups, the photoperiodic changes by long days inhibited the testosterone secretion. Testicular volume was higher during normal days than long days although the amplitude of the variations was reduced compared to control groups. In photoperiod treated groups, testosterone secretion increased after 2 weeks of exposure to normal days and decreased within a 4 weeks after the beginning of exposure to long days. During the long day treatment (February to March), the sperm production decreased on experimental animals. After stopped the photoperiodic treatments and the bucks remained on natural photoperiod from mid-March, was observed an increase of sperm production from March to May.

Sogorescu E.,Ovidius University | Zamfirescu S.,Ovidius University | Anghel A.H.,Icdcoc Palas | Nadolu D.,Icdcoc Palas | Rosoiu N.,Ovidius University
Journal of Animal and Veterinary Advances | Year: 2012

Reproductive seasonality is a major limitation in goat production on temperate and subtropical regions. The objective of this study was the characterization of the seasonal variations of progesterone level, length of oestrus cycles, breeding season and anoestrus period on Carpathian goats. The breeding season on Carpathian goats was observed between late Septembers to early March with peak of reproductive activities on November to February when day length was short. In breeding season the Carpathian goats presents the cyclic variations of progesterone concentrations. The anoestrus period starts in late March and finish in middle September. © Medwell Journals, 2012.

Sogorescu E.,Ovidius University | Zamfirescu S.,Ovidius University | Anghel A.H.,Icdcoc Palas | Nadolu D.,Icdcoc Palas
Romanian Biotechnological Letters | Year: 2010

The information known at the moment on the follicular development, the in vitro maturation of oocytes, the in vitro fertilization of oocytes and the development of zygotes at blastocyst stage are possible with the technical molecular biology. The objective of our research between 10.25- 11.20.2009 was the testing of the new media for observing the developmental competence of goat and sheep oocytes, within the pilot station for the gene preservation, The Laboratory of Sheep and Goat Reproduction and Biotechnologies within ICDCOC Palas. The ovaries were collected from Carpathian goats immediately after slaughter and the cumulus-oocyte complexes were obtained by aspiration of large follicles and mechanical dissection of follicles. The goat cumulus - oocytes complexes were selected on the basis of morphological criteria for testing 7 versions of oocytes maturation media supplemented with natural extracts. Better results were obtained for 2 versions of goat oocytes maturation: PBS medium supplemented with 100 μl/ml cysteamine, 20 ng/ml of epidermal growth factor and 50 ng/ml pFSH and TCM 199 medium (1,5 g/250 dl stock solution), 20 ng/ml of epidermal growth factor, 50 ng/ml pFSH and 10% cucumber juice. The most commonly used system for the maturation of oocytes outside the follicle is a culture medium supplemented with FSH, LH , estradiol and 10% fetal calf serum (FCS). The percentage of mature oocytes cultured in a 5% CO2 humidified air atmosphere at 38 °C, for a period of 17 h was 93,75%. The sheep cumulus-oocytes complexes were collected surgically and after slaughter from Merinos of Palas sheep. The cumulus-oocytes complexes were obtained by aspiration of follicles using an 18-gauge needle fitted with a 2 ml syringe. The cumulus-oocytes complexes covered by at least 2 layers of granulose cells were selected for in vitro maturation. The mediums used for maturation of sheep cumulus -oocytes complexes were TCM 199 medium supplemented with 10% follicular liquid and TCM 199 medium supplemented with 5% Epidermal Growth Factor. In vitro maturation conditions were 5% CO2 in humidified air at 37°C for 24 h. The action of maturation medium (TCM 199) supplemented with follicular liquid at oocytes development was better then medium-199 with EGF (71.42 % vs 64.28 %). © 2010 University of Bucharest.

Anghel A.H.,Icdcoc Palas | Nadolu D.,Icdcoc Palas
Annals of the Romanian Society for Cell Biology | Year: 2011

The photoperiod is the primary environmental used to regulate reproduction. On the basis of this knowledge, we studied the bucks maintained under ambient photoperiod and normally fed diet. The bucks groups are maintained in an intensive breeding system in closed and semi-opened shelters which respect the farm norms (space/animal 1,5-2m/goat, normal temperature conditions, 18-30 0C in summer and 6 0C in winter, < 75% humidity). The scientifically research were realized on the Laboratory of Cell and Molecular Biology on the Faculty of Natural and Agriculture Sciences during January - March 2010. The objective of scientifically research was to observe the variations of testosterone concentration in correlation with testicular volume at Carpathian bucks. The means of testosterone concentration for all 10 bucks were increased in January and February (3,27±1;0,94 ng/ml vs 2,33±1; 0,64 ng/ml) and down immediately in March (1,06±1;1,14 ng/ml). Testicular volume was influenced by diet and photoperiod with significant interaction between these effects. Testicular volume on bucks was higher for January comparative with February (274 ±1;1,34 g vs 242,5±1;0,83 g). The monthly mean of testicular volume was lowest into early spring (March 199 ±1;0,45 g) comparative with winter months (January -February). However, changes in testicular volume (and therefore sperm production) appeared to be driven primarily by changes in the voluntary intake of feed and in growth, often independently of changes in gonadotrophin concentration. Enhanced nutrition is thus able to induce rapid testicular growth, but not increased testosterone production, during winter and spring when photoperiodic inhibition of the hypothalamo-pituitary-testicular axis is maximal.

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