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At least 37 records · Page 2Linked to original sources
PubMed1997

Lipid and antioxidant changes in spermatozoa and seminal plasma throughout the reproductive period of bulls.

The lipid compositions and associated antioxidant capacities of spermatozoa and seminal plasma from bulls were examined at the beginning, middle and end of their reproductive period. The reduction in concentration and motility of spermatozoa associated with ageing was accompanied by a large decrease in lipid concentrations within the seminal plasma; this change in lipid concentration was accompanied by an increase in the proportion of phospholipid. By contrast, the proportion of phospholipids in the spermatozoa was significantly reduced. The major phospholipid fractions within both the spermatozoa and seminal plasma were phosphatidyl choline and phosphatidyl ethanolamine. With increasing age there was a large decrease in the proportion of phosphatidyl ethanolamine and a commensurate increase in that of phosphatidyl choline within the spermatozoa and seminal plasma. These major changes in phospholipids were accompanied by a decrease in the amount of phosphatidyl inositol and an increase in that of cardiolipin in both spermatozoa and seminal plasma. The reductions in the proportions of phosphatidyl ethanolamine were accompanied by extensive reductions in the content of the major polyunsaturated fatty acids, arachidonic 20:4 (n-6) and docosahexaenoic 22:6 (n-3); there was a decrease also in the concentration of 22:6 (n-3) in phosphatidyl choline. The changes in lipid composition owing to ageing were associated with a marked reduction within the seminal plasma of the major antioxidant enzyme systems, glutathione peroxidase and superoxide dismutase.

Aging↗
PubMed1984

Plasma sex hormones and post-reproductive period in the green frog, Rana esculenta complex.

The plasmatic profiles of androgens, estradiol, and progesterone, together with gonads and SSC modifications, have been followed, throughout the post-reproductive period in two Rana esculenta populations, inhabiting, respectively, a mountain pond (Colfiorito) and a sea level lagoon (Lesina). Testosterone and progesterone progressively decrease in the blood until July, while estradiol shows, in both sexes, an increase in the same month. Testosterone depletion accounts for thumb pad atrophy in the male and probably, in both sexes, for the summer interruption of sexual behavior. The estradiol increase could be linked to the induction of vitellogenin synthesis by the liver or, alternatively, could act through negative feed-back on the brain centers involved in GnRF synthesis and therefore it could be responsible for an inhibition of LH release and, in turn, of androgen synthesis/secretion by the gonads. The last function can be framed in the endocrine regulation of the so-called "refractory period" which interrupts the breeding during the summer. The hematic level of progesterone is higher during the ovulation period and this is consistent with the role assigned to the hormone, i.e., the induction of jelly release from oviductal glands. The hormonal trends in the blood of the two frog populations are very similar, although some differences exist in the levels of testosterone and progesterone.

Animals↗
PubMed2000

Liver total lipids and fatty acid composition of shot red and fallow deer males in various reproduction periods.

In this study total lipid (TL) content and the fatty acid composition changes in the liver of red deer stags (n=35) and fallow deer bucks (n=19) were examined at various reproductive stages. Samples were taken from mature red deer stags in the rut (September), in the post-rut (October), at the end of the rut (November) and after sexual activity had ceased (January). Sampling from mature fallow bucks was performed in the pre-rut (early October), in the rut (November) and after the reproduction period (January). The results obtained indicated significant (P<0.001) fatty degeneration of the liver in the males at the rutting season. At that time the TL concentration (x+/-S.D. in wet weight) was 156+/-40 g/kg in the red deer stags and 405+/-46 g/kg in the fallow bucks. Subsequent to the rutting season this value decreased to 47+/-15 g/kg by November in the red deer stags and to 51+/-3 g/kg by January in the fallow bucks. Significant changes were also observed in the fatty acid composition of the liver lipids, determined by gas chromatography. Liver samples collected during the rutting season from both red deer stags and fallow bucks showed higher (P<0.001) total proportions of monounsaturated fatty acids and lower (P<0.001) weight percentages of polyunsaturated fatty acids than those taken in January. In comparison with January the liver samples taken in September from red deer stags showed significantly higher (P<0.001) proportions of fatty acids C14:0, C15:0 and C:16:1, and significantly lower (P<0. 001) proportions of C18:0, C20:4 (n-6) and C22:5 (n-3). The proportions of C14:0, C15:1, C17:1 and C18:3 (n-3) in the liver samples taken in November from fallow bucks were higher (P<0.001), while the proportions of C18:0 and C20:4 (n-6) were lower (P<0.001) than those measured prior to rutting (in October) or after the rut (in January).

Analysis of Variance↗
PubMed1992

In vivo and in vitro studies on the effects of mGnRH on oestradiol-17 beta inter-renal production in the female frog, Rana esculenta, during the post-reproductive period.

Plasma oestradiol-17 beta was measured by RIA, in female, Rana esculenta, submitted to hypophysectomy, gonadectomy, or both, and treated with mammalian gonadotropin-releasing hormone (mGnRH), homologous pituitary homogenate, or both, during the post-reproductive period. In addition, the oestradiol-17 beta release was measured in in vitro incubations of ovaries or interrenals treated with mGnRH, pituitary, or both, during the same period. In vivo and in vitro mGnRH and/or pituitary directly stimulated the production of oestradiol-17 beta by the interrenal, but not by ovary, although the stimulatory effects of the pituitary are minor and delayed with respect to those of mGnRH. These results seem to indicate that mGnRH and pituitary, with probably different mechanisms, stimulate the interrenal to produce high levels of oestradiol which is involved in the post-reproductive refractoriness.

Animals↗
PubMed1996

Reproductive period affects water intake in heat-stressed dehydrated goats.

Water intake following dehydration was studied in pregnant (N = 5), lactating (N = 4) and nonpregnant, nonlactating (N = 5) Swedish domestic goats (Capra hircus) to investigate if reproductive period affected drinking. Plasma cortisol concentration and the hematocrit value were measured to evaluate stress. The goats were water deprived from 9.00 h until 15.05 h the next day. They were fed at 7.00 and 15.20 h. On the second day, ambient temperature was increased from 20 degrees C to 38-39.5 degrees C for 5.15 h to accelerate water losses. Water temperature during rehydration was 35 +/- 1 degree C. Plasma Na concentration and osmolality increased most in dehydrated and heat-stressed pregnant and lactating goats. Pregnant goats lost 2.2 kg of their body weight. They drank 3.5 l immediately, followed by 2.5 l during afternoon eating. Lactating goats lost 4.9 kg and drank 6.3 l at once, and 3.9 l during feeding. Nonpregnant, nonlactating goats lost 1.7 kg and drank 2.6 l followed by 0.6 l. The large water consumption in pregnant and lactating goats caused hyponatremia and hemodilution, but they continued to drink during the night (0.5 +/- 0.2 l and 0.8 +/- 0.5 l, respectively). Renal free water clearance increased in all periods, with a long-lasting water diuresis during pregnancy. Plasma cortisol concentrations and the hematocrit values rose in connection with water intake. These results imply that the thirst center became less sensitive to inhibitory signals from the oropharyngeal tract and the diluted blood plasma during pregnancy and lactation. Catching sight of water was the most exciting procedure during these experiments.

Animals↗
PubMed1976

Seasonal reproductive periodicity and thyroid fluctuations in female Indian palm squirrel, Funambulus pennanti.

Seasonal reproductive rhythmicity and concomitant thyroid fluctuations have been studied in the female Indian palm squirrel, Funambulus pennanti. The majority of the squirrels enter estrus during March and April when ovarian follicles attain maximum diameter. Ovulation starts in April and continues till June. A large number of degenerating follicles, indicating decline in ovarian functions, is a characteristic feature of the ovary in August. Minimum percent thyroid 131I uptake is recorded during May and June, i.e. at the onset of mating season. In July, which also marked the gestation period in the majority of the squirrels dissected, thyroid activity significantly increases. Gonadal regression begins in August and this is accompanied by corresponding fall in the thyroid 131I uptake. Alterations in thyroid cytoarchitecture during different months of the year are in accordance with the results obtained from radioiodine uptake studies. Fluctuations in thyroid functions during gonadal regression, recrudescence and peak gonadal activity are discussed in the present communication.

Animals↗
PubMed1977

Diagnostic irradiation of women during the reproductive period.

The date of onset of the last menstrual period should be given on radiographic requisitions for all women of reproductive age. Every effort should be made to avoid unnecessary irradiation of any woman who might be pregnant. Radiation damage in the first 2 weeks of pregnancy, however, should be "all or none", resulting in either a miscarriage or a normal child. Diagnostic radiology procedures are not indications for therapeutic abortion. Ultrasound has now replaced ionizing radiation in most examinations of the fetus and placenta. Pelvimetry should be done only when the decision to do a cesarean section hinges on precise knowledge of measurements of the bony pelvis. On the rare occasion when a radiograph of the fetus is necessary the woman should be prone for the examination. All such examinations are best ordered after consultation with a radiologist. Radiography of distant areas with the beam directed away from the woman's abdomen can be done without concern at any stage of pregnancy.

Abortion, Therapeutic↗
PubMed2006

Rubella seroprevalence in women in the reproductive period, Mersin, Turkey.

The aim of this study was to determine the rubella seroprevalence in women of reproductive age. This cross-sectional study was conducted on women aged 15-49 years. Serologic studies were performed by using the ELISA method. The number of women enrolled in the study was 607, the mean age was 30.7+/-9.3 years and 13.2% of the participants were living in the rural area. Rubella seroprevalence was 55.0%. This ratio was 77.5% in women living in the rural area (p<0.001). There were no statistically significant correlations between immunity to rubella and other socio-demographic characteristics. In conclusion, women in this age group are advised to have a single dose of rubella vaccination in order to avoid CRS before pregnancy.

Adolescent↗
PubMedDate not supplied

Normal values in adult Zambians. X. Serum follicle stimulating hormone (FSH) in normal Zambian males and females in the reproductive period of life; estimation by the radioimmunoassay kit.

Serum follicle stimulating hormone (FSH) was measured in healthy Zambians in the reproductive phase of their lives, using the radioimmunoassay kit. In males the mean serum FSH level was 7.10mlu/ml. In females, the mean serum FSH level was 9.05mlu/m. These results compare favourably with results obtained by non-kit radioimmunoassay. Furthermore, they are similar to results obtained by other workers in the same phase of life in Caucasians.

Adult↗
PubMed1994

Plasma thyroxine concentration in non-pregnant and lactating mink, and effect of dietary rapeseed oil in the reproduction period.

Effect of dietary rapeseed oil from 00-varieties of rapeseed (0, 1.5% or 3% respectively in the wet compounded diets) on plasma thyroxine (T4), reproductive performance and kit weight gain during lactation was investigated with 3 groups of each 20 mink females. Plasma T4, which has not previously been reported for female mink, was significantly lower in lactating than in non-pregnant females. Unlike in an earlier experiment with growing male mink, it was not affected by dietary rapeseed oil. Reproductive performance, female weight development, feed consumption, and kit weight gain was normal in all treatment groups and there were no significant effects of the experimental treatment.

Abortion, Veterinary↗