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PubMed1995

Prostaglandin F(2alpha) and naloxone therapy in the anestrous postpartum beef cow.

Three experiments were conducted, using multiparous crossbred beef cows, to test the ability of exogenous prostaglandin F(2alpha) (PGF) and/or naloxone to reduce the duration of the postpartum interval to estrus and to improve subsequent reproductive performance. In each experiment, postpartum cows were assigned to treatments by calving date. In Experiment 1, cows (n=44) were assigned to 1 of 4 treatment groups: 1) control, 2) PGF on Day 25 post partum, 3) 400 mg naloxone (3 doses) at 12-h intervals on Day 30 post partum, and 4) PGF on Day 25 followed by 3 400-mg doses naloxone at 12-h intervals on Day 30 post partum. In Experiment 2, cows (n=126) were assigned either to 1) control or 2) PGF on Day 30 post partum In Experiment 3, cows (n=67) were again assigned to 1 of 4 treatments 1) control, 2) PGF on Day 30 post partum, 3) PGF on Day 40 post partum, and 4) PGF on Day 30 and 40 post partum. Serum progesterone was used to determine the postpartum interval to estrus in Experiments 1 and 3. In all 3 experiments, serum progesterone was used to determine the proportion of cows that had reestablished estrous cycles at the start of breeding. Pregnancy rate and calving interval were analyzed for all trials. Naloxone had no effect (P > 0.20) on any reproductive variable measured. The postpartum interval to estrus was similar (P > 0.30) for PGF-treated and control cows in Experiments 1 and 3. The proportion of cows cycling at the start of breeding and the calving interval were not affected (P > 0.20) by PGF treatment in any of the experiments. Only the administration of PGF on Day 40 post partum in Experiment 3 improved (P=0.04) the subsequent pregnancy rate. Analysis of data pooled across experiments showed that the pregnancy rate was higher (P=0.03) for cows treated with PGF than for control cows (91.4 and 72.9%, respectively). It was concluded that administration of PGF during the early postpartum period improves subsequent reproductive function in beef cows.

Journal Article↗
PubMed2006

Morphological changes in the clasper gland of the Atlantic stingray, Dasyatis sabina, associated with the seasonal reproductive cycle.

The clasper gland of the Atlantic stingray, Dasyatis sabina, was examined over a 1-year period, covering an entire reproductive cycle. Changes in clasper gland tissue architecture, fluid production, and cell proliferation were assessed. No changes in tissue architecture were observed. Evidence of cell proliferation in the gland epithelium was not detected using immunocytochemistry for proliferating cell nuclear antigen, a cellular marker of mitosis. Epithelial cells were not observed to undergo mitosis, and cell membranes remained intact. The lack of structural changes and epithelial cell proliferation supports the proposed merocrinal mode of fluid secretion. Rays captured in nonbreeding months had clasper glands that exhibited tubules with reduced lumens. In contrast, rays caught during the breeding season had clasper gland tubules with enlarged lumens. Clasper gland fluid production was quantified through measurements of the fluid area and tubule area calculated from digital images. Clasper gland fluid production was significantly higher during the mating period than during months not associated with copulatory activity. These data support the notion that the clasper gland is involved in stingray copulatory activity. This study adds to the limited amount of literature focused on this poorly understood component of reproduction in skates and rays.

Animals↗
PubMed1955

Reproduction of influenza viruses; quantitative investigations with particle enumeration procedures on the dynamics of influenza A and B virus reproduction.

Influenza A and B virus reproduction in the allantoic membrane of the intact chicken embryo was studied quantitatively with particle enumeration procedures. Virus particles were enumerated on the basis of two independent properties; capacity to infect and to cause hemagglutination. The infective property of influenza B virus (Lee) was even more unstable than that of influenza A virus (PR8). Inactivation occurred at a constant logarithmic rate which was independent of the concentration of particles and corresponded with first order reaction kinetics. In allantoic fluid at 35 degrees C. either in vitro or in vivo, Lee virus had a half-life for infectivity of only 85 minutes. In contrast, the hemagglutinating property, like that of PR8, was relatively stable and was not appreciably affected by 12 hours at 35 degrees C. On the basis that the number of non-infective particles is equal to the number of hemagglutinating particles minus the number of infective particles and that the number of cells lining the allnatoic membrane is 1.8 x 10(7), the effects of various particle-cell ratios on the reproductive process were analyzed. Adsorption of infective and non-infective Lee particles occurred at the same logarithmic rate, i.e. about 50 per cent in 72 minutes, and the rate was nearly independent of the particle-cell ratio up to a value of 55. The adsorption capacity of an allantoic cell was at least 44 Lee or 89 PR8 particles. The interval before new particles appeared in the allantoic fluid increased as the particle-cell ratio was decreased with both Lee and PR8. At ratios of 0.2 or less, the appearance time for infective particles was nearly identical to that for hemagglutinating particles with both viruses. At ratios of about 1.0, the "latent period" in the allantoic membrane per se was computed to be 150 to 160 minutes for both Lee and PR8. The number of particles, both infective and hemagglutinating, increased at a constant logarithmic rate for 6 hours or more after the adsorptive period. With Lee virus, at a particle-cell ratio of 5 or less, the doubling time was constant and had a value of 43 minutes. The dynamics of the logarithmic increase period suggest that reproduction corresponds to an autocatalytic reaction in which the rate is proportional to the amount of material produced. When the particle-cell ratio was increased to 10 or more, either with infective or non-infective (inactivated at 35 degrees C. or 22 degrees C.) particles, the doubling time increased to 65 minutes. Comparable effects from high ratios were found with PR8. Non-infective particles accumulated at a rapid rate after the interval of constant logarithmic increase regardless of the particle-cell ratio. This accumulation was even more striking with Lee than with PR8 as was expected because of the shorter half-life of the infective property. With both viruses at particle-cell ratios of 4 or more, a large proportion of the particles were non-infective within a few hours after new particles appeared. At particle-cell ratios of 0.2 or less, the maximal yield was relatively constant, i.e., about 900 to 1400 hemagglutinating particles per cell with Lee and 500 to 900 with PR8. However, even with very low ratios, i.e. 0.001 or less, it was not possible to obtain more than about 160 infective particles per cell with either virus regardless of the interval. As was expected, the lower the ratio, the longer was the interval before maximal yields were produced. At ratios of about 10, the maximal yield was reduced by 50 per cent or more with both viruses. Comparable reductions in yield were obtained whether the high particle-cell ratio was due to infective or non-infective (inactivated at 35 degrees C. or 22 degrees C.) particles. These findings indicate that there is a critical particle-cell ratio above which alterations appear in the dynamics of reproduction of influenza viruses. This ratio has a value of approximately 3. The observed alterations in the reproductive process are discussed in relation to the hypothesis that adsorption of 3 or more infective or non-infective particles per cell induces cell damage.

Animals↗
PubMed2006

Infertility and assisted reproduction in Denmark. Epidemiology and psychosocial consequences.

Clinically a couple is considered to be infertile after at least one year without contraception and without pregnancy. There was scant knowledge about the prevalences of infertility, involuntary childlessness and the seeking of fertility treatment and only few longitudinal studies about the psychosocial consequences of infertility and its treatment. This thesis is about the epidemiological aspects of infertility; the conceptualization and measurement of important psychosocial aspects of infertility; and a medical sociological analysis of the associations between these psychosocial variables among Danish women and men in fertility treatment. The thesis is based on nine papers. The three main purposes were: (i) to review critically, population based studies of infertility and medical care seeking in industrialised countries. Further, to examine these prevalences and subsequent motherhood among women in former assisted reproduction in a Danish population. (ii) To develop measures of psychosocial consequences of infertility: fertility problem stress, marital benefit, communication, coping strategies, attitudes to and evaluation of fertility treatment. (iii) To examine these phenomena and to analyse their interrelations among Danish women and men in fertility treatment. The thesis is based on four empirical studies: (i) The Women and Health Survey, a cross-sectional population-based study among 15-44 year old women (n=907, 25-44 year old) in Copenhagen County, 1989. (ii) The Psychosocial Infertility Interview Study, a qualitative interview study among 16 couples (n=2 participants) infertility treatment at The Fertility Clinic, Herlev University Hospital,1992. (iii) The Infertility Cohort, a longitudinal cohort study consecutively including all couples (n=250 participants) beginning anew fertility treatment period at one of four public (Braedstrup, Herlev, Odense, Rigshospitalet) and one private fertility clinic (Trianglen),2000-2002. (iv) The Communication and Stress Management Training Programme, an intervention study among couples(n=74 participants) in fertility treatment at The Fertility Clinic, The Juliane Marie Centre, Rigshospitalet, 2001-2003. Included is also a literature review of population-based infertility studies from industrialised countries. Data from (iii) and (iv) are studies from The Copenhagen Multi-centre Psychosocial Infertility (COMPI) Research Programme (www.compipro.dk). Epidemiological and demographic studies investigating the prevalences of infertility differed in how they defined the numerator (the infertile participants) and the denominator (the population at risk). It was important to calculate reliable estimates of the infertility prevalence by including only women who had tried to have at least one child in the population at risk, as a notable proportion of women in the fertile ages had not (yet) attempted to become a mother. The lifetime prevalence of infertility in the representative population-based study was 26.4%. In the age group 35 to 44 years 5.8% were primarily involuntarily in fecund (involuntarily childless). Even in a country with access to fertility treatment in a public health-care system without self-payment lower education was a predictor of lower treatment seeking. In the cohort study (2000-2002)of couples starting a new period of assisted reproduction treatment 62.6% reported a treatment-related pregnancy at the one-year follow-up. In total 32.4% reported a treatment-related delivery. In total 24.2% reported a current continuing pregnancy and spontaneous pregnancies accounted for 2.7% of these. We developed measures of fertility problem stress, marital benefit(that infertility has brought the partners closer together and strengthened their marriage), partner communication, infertility related communication, coping strategies, attitudes to fertility treatment and evaluation of care. The medical sociological analyses showed that the variables of psychosocial consequences of infertility and treatment are interwoven with each others in a complex pattern, a pattern that both differed and was similar when comparing women and men. The infertility-related communication strategy (secrecy, formal, open-minded)identified in the qualitative interviews was later confirmed in the COMPI Infertility Cohort. Using the formal strategy and not talking about the emotional aspects of infertility and its treatment suggested high fertility problem stress. The coping strategies studied showed significant social differences and active-avoidance coping was a significant predictor of high fertility problem stress. A positive effect of infertility on the marriage, marital benefit was common. Men using the secrecy communication strategy had increased risk of low marital benefit. Difficult partner communication was a significant predictor of high fertility problem stress and among men, of low marital benefit. The intervention study showed that it was possible for the participants to change their communication with partner and other people close to them and that participants achieved an increased awareness of what, how much and when to discuss with others. High fertility problem stress and high marital benefit were associated with high importance ratings of patient-centred care and intentions to use professional psychosocial services. Among women, high fertility problem stress was a predictor of lower satisfaction ratings with fertility treatment. High marital benefit was a predictor of high satisfaction ratings of both medical and patient-centred care. In conclusion, infertility is a common experience among couples attempting to become parents. Assisted reproduction in the public health-care system in Denmark has high success rates, i.e. pregnancies,deliveries and high patient satisfaction. A large minority of people in fertility treatment experience high fertility problem stress,and some use communication and coping strategies that predicts high stress. Developing and evaluating different psychosocial interventions are necessary to offer the psychosocial support needed for this minority of fertility patients.

Adaptation, Psychological↗
PubMed2006

Ovarian activity and oestrous signs among group-housed, lactating sows: influence of behaviour, environment and production.

Animal welfare concerns require the development of housing systems that allow the animals to express their natural behaviour. One example of this is the group-housing system for lactating sows. The present study aimed at exploring ovarian activity in such a system. Thirty-eight sows farrowing individually outdoors during spring and summer, and indoors during autumn and winter, and group-housed in groups of four during weeks 3-7 of the lactation period, were monitored regarding reproductive functions, behaviour and production during their first to fourth lactation period. Average ovulation frequency during lactation was 47%. Only 50% of these ovulating cases were accompanied by a standing oestrus. Lactational ovulation frequency was higher in later parities (p < 0.001). Ovulation frequency was higher (p < 0.05) during winter (74%) and spring (69%), than during summer (10%) and autumn (23%). Occurrence of lactational ovulation was associated with some aspects of suckling behaviour and also with litter weight gain (p < 0.05). Forty-nine per cent of the lactational ovulations occurred during the seventh week of lactation. Timing of ovulation seemed positively (p = 0.08) associated with weight loss during lactation. Compared with the sows that were anoestrus during lactation, oestradiol-17beta values were higher (p < 0.05) only in the week before occurrence of lactational ovulation. Weaning-to-oestrous interval was prolonged (p < 0.05) among the sows that ovulated during lactation. The present study identifies several factors influencing ovarian activity among group-housed sows, thereby providing tools for the control of lactational ovulation in group-housing systems.

Animal Husbandry↗
PubMedDate not supplied

[Long-term dynamic of fecal corticosterone and its ecological and social correlates in males of great gerbil (Rhombomys opimus Licht.). Non-invasive approach in studies of stress in natural populations].

The relationship between fecal corticosterone concentrations and characteristics of the environment and population demography were studied in adult male gerbils (Rhombomys opimus Licht.) at the southern border of Kyzylkum desert (Reserve "Ecocentre Dzeiran", Bukhara region, Republic Uzbekistan) in spring and fall seasons from 1999 to 2004. We extracted hormones from air-dried fecal samples and analyzed their concentrations by radioimmunoassay (Gerlinskaya et al., 1993). An analysis for year-specific relationships between hormone concentrations and environmental variables of temperature and precipitation using Pearson's r statistic revealed that corticosterone concentrations correlated positively with total precipitation in January and February and negatively with precipitation during March and April. There was also a significant negative relationship between fecal corticosterone and the number of hot days in March (>20 degrees C). Demographic variables that characterized population densities (percent of burrow systems occupied, mean and maximum number of burrow systems/1 ha, number of females in the burrow system) correlated positively with corticosterone concentrations in feces in the beginning of spring, but these relationships were small compared with mean concentrations of corticosterone for the entire spring season that were strongly and positively correlated with number of gerbils, including all pups emerged, in burrow systems owned by one male (within its home range). In contrast, correlation coefficients of corticosterone concentrations with characteristics of feeding resources in the spring were low and negative. In the long-term perspective (interannual comparison), mortality among adult males was highly negatively correlated with mean corticosterone concentrations in the beginning of spring, which is within the period of maximum reproductive effort and potential stress. Body mass was independent of corticosterone concentrations in males in either the beginning of spring, or during the whole spring. In the fall, mean concentrations of fecal corticosterone in males was positively correlated with the number of days from June to October with mean daily temperatures exceeding 30 degrees C, and with percent of burrow systems where at least one adult, > or = 1 year old gerbil had survived. Mortality from fall to spring of the next year and the fall body mass did not correlate with concentrations of corticosterone in feces collected in the fall. When we analyzed corticosterone concentrations in spring seasons of all years combined using a stepwise regression analysis of a sampling of individual males (we analyzed residuals after withdrawal of year effect) on a set of variables representing habitat resources, distances between nearest neighbor males, and variables representing group demography we found low R2 values not exceeding 0.17. Within the six-year period, concentrations of corticosterone in the spring related negatively with abundance of annual herbs and positively with number of females in a male's social group. When only years of high density were analyzed, fecal corticosterone concentrations in males in the spring were again negatively determined by abundance of herbs, as well as by the nearest neighbor distance, and positively determined by the number of females within a male's home range. At the beginning of spring the only determinants were distance to the nearest neighbor male and number of females. In years of low density none of the variables were found to affect corticosterone levels during the whole spring, while in the beginning of spring only partial regression coefficients of abundance of herbs were negative and significant. Stepwise logistic regression analysis revealed positive dependence (P = 0.05) of disappearance of adult males during summer drought on concentrations of fecal corticosterone in the spring, but only when burrow systems with at least one adult (male or female) surviving after the summer were considered. Our results provide evidence ground for the assumption that in a desert rodent with non-regular population fluctuations such as the great gerbil, density may be more suppressed by external factors and not by density dependent mortality mediated by stress. Density dependent increases of stress caused by intense reproductive effort occurred when feeding and climatic conditions were favorable to compensate for negative effects on survival. However, in individual gerbils mortality mediated by stress can take place because we found higher stress in the beginning of spring in males, which did not occur in the population after the summer drought.

Animals↗
PubMed2001

Screening of four species of detritivorous (humus-former) earthworms for sustainable vermicomposting of paper waste.

Four specices of detritivorous (humus-former) earthworms were tested for their ability to vermicompost paper waste blended with cowdung in 6:1 (w/w) ratio. The anecic Lampito mauritii, Kinberg and the epigeic Eudrilus eugeniae, Kinberg were the most effective of the four species employed; 20 animals of each of these species generated castings amounting to about 52% of the feed mass (75 g) per fortnight. The performance of these two species was followed by the anecic Drawida willsi, Michaelsen and the epigeic Perionyx excavatus, Perrier; they achieved approximately 46% vermiconversion in comparable settings. The vermireactors were sustainable as the animals have remained consistently healthy and reproductive over a period of six months, and are continuing to remain so, turning in a steadily rising vermicast output. During this period E. eugeniae have grown to 2.3 times their original weight while the other three species have more than trebled their weights. The studies establish the feasibility of vermicomposting as a viable process for the gainful utilization of paper waste in an environmentally clean manner. They also indicate that all the four species of the worms screened by us are suitable for the process, with L. mauritii and E. eugeniae a shade more efficient than the other two species.

Animals↗
PubMed1998

Relationship of gestation protein and feed intake level over a five-parity period using a high-producing sow genotype.

High-producing Landrace-Large White crossbred gilts (n = 50) involving 198 farrowings were used to evaluate dietary gestation protein (13 vs 16% CP) and gestation feed intakes (Control vs High), and their interaction, over a five-parity period on sow reproductive performance. Gestation feed intake for Control was 1.81 kg/d during parity 1, increasing by .09 kg for each successive parity. The daily feed intake for High was greater by .13 kg or approximately 450 kcal ME at each respective parity. The experiment was a 2 x 2 in a randomized complete block design conducted in two replicates with parity nested within sow groups. Sow weights and backfat thickness were determined at various intervals. A lactation diet containing .90% lysine in parity 1 and .80% lysine during parities 2 to 5 was fed to all sows from farrowing to weaning (21 d). Sow and pig weights, feed intakes, and colostrum and 21-d milk samples were collected during each lactation. The High feed intake and the 13% protein diet resulted in greater (P < .01) backfat thicknesses, and the effects were additive. Backfat thickness declined quadratically (P < .01) by parity and from late gestation to the rebreeding period of the following parity. The High feed intake resulted in a larger litter size (P < .01), whereas dietary gestation protein concentration had no effect on parturition performance. Sows in each parity consumed more (P < .01) feed from 0 to 7 d postpartum and for the overall 21-d lactation period (P < .01) for parity 1 when the 16% gestation protein had been fed. Gestation feed intake regimens did not affect lactation feed intake. Neither gestation variable affected colostrum or 21-d milk fat, but concentrations declined (P < .01) in all groups after parity 2. Parity 1 litters were heavier at 14 and 21 d, with larger litter gains from 0 to 14 and 0 to 21 d when gestating sows had been fed the 16% protein and the High feed intake combination compared to the other sow treatment groups. From parity 2 to 5, litter weights and gains were similar for all treatment groups. This resulted in a three-way interaction response (P < .05) for these variables. These results suggest that primiparous sows required a greater gestation protein concentration and greater feed intake than generally recommended, but the 13% CP diet at the High feed intake was effective in older sows.

Adipose Tissue↗
PubMed2006

Factors affecting walking activity at estrus during postpartum period and subsequent fertility in dairy cows.

The postpartum period is critical for efficient reproduction, and certain features of the normal estrus cycle during this period have been associated with subsequent reproductive performance. The objectives of the present investigation were to evaluate the effects of environmental, production, and reproductive factors on walking activity at estrus as determined using pedometers during the first 50 days in milk (DIM) (study 1). In a second study, we tried to establish whether pedometer measurements recorded during this period could be used to predict subsequent fertility by considering the number of cows becoming pregnant before 90 DIM. We analyzed data derived from 995 parturitions in a single herd. Detection of estrus was performed using a pedometer system. Variables were screened for associations with walking activity by analysis of variance (ANOVA) through generalized linear model procedures (PROC GLM). Increased milk production and parity, and a mean relative humidity (RH) higher than 95% were associated with lower pedometer measurements. A higher number of animals simultaneously in estrus rendered higher pedometer readings. No significant effects of the year, season, DIM, number of previous estruses, and climatic data other than high mean RH were observed. Relationships between pedometer measurements and other variables recorded during the first 50 days postpartum, and subsequent fertility were assessed by applying logistic regression models. We detected no significant effects of year, milk production, season, and mean activity increase at estrus on high fertility. The likelihood of pregnancy before 90 DIM decreased for each additional lactation and for cows in anestrus between days 0 and 50 postpartum. However, pedometer readings during the first 50 days postpartum were unable to accurately predict subsequent fertility.

Analysis of Variance↗
PubMed1995

Endogenous gonadal, LH and molt rhythms in tropical stonechats: effect of pair bond on period, amplitude, and pattern of circannual cycles.

To investigate the effects of reproduction and associated stimuli on the circannual cycles of African stonechats Saxicola torquata axillaris birds were held for 29 months in aviaries under a constant equatorial (12.25 h) photoperiod, either singly (10 females and 10 males) or in 10 male/female pairs. The birds of all 3 groups went through circannual cycles in gonadal size, plasma LH and molt, but groups differed with regard to actual reproductive performance. During the second cycle, only one of the singly-held females laid eggs and incubated. In contrast, in the paired females egg-laying and incubation occurred in all but one bird. About 50% of the clutches from paired females contained fertilized eggs confirming the expectation of behavioral differences between the paired and unpaired birds. However, despite differences in reproductive performance there were no differences in either circannual period or duration of reproductive phases. Moreover, there was no correlation between number of broods produced per season and circannual parameters of the paired females. Therefore, the temporal course and, particularly, the period during which reproduction is possible is rigidly determined by an endogenous program that is not influenced by reproductive performance. A rigid program of this kind may be advantageous in the tropics because it prevents prolongation of the breeding season in years with favourable conditions which in turn could jeopardize optimal timing of breeding in the following year and thus reduce lifetime reproductive success.

Africa↗
PubMed2003

Effects of tributyltin chloride on the reproductive system in pubertal male rats.

Detrimental effects of tributyltin (TBT) chloride on the reproductive system were investigated in pubertal male rats. Sixty Sprague-Dawley rats aged with 35 days were assigned to six different groups; negative control receiving vehicle, positive control receiving methyltestosterone (10 mg/kg B.W.), TBT chloride (5 mg/kg B.W., 10 mg/kg B.W., and 20 mg/kg B.W.), and a combination of TBT chloride (10 mg/kg B.W.) and flutamide (10 mg/kg B.W). The animals were treated with test compounds by oral gavage daily for 10 days and sacrificed on the next day of the final treatment. The treatment with TBT chloride at the doses of 10 and 20 mg/kg B.W. significantly decreased seminal vesicle weights, compared to the negative control. The combined treatment of TBT chloride and flutamide caused a significant decrease in accessory sex organ weights, compared to the control and TBT chloride treatments. The treatment with TBT chloride or in the combination with flutamide increased detached debris and sloughed cells in the tubules of epididymis and narrowed seminal vesicles. In addition, the combined treatment with TBT chloride and flutamide caused a noticeable increase in serum androgen level, compared to the negative control. These results suggest that TBT chloride exposed during pubertal period cause partial reproductive disorders in male rats.

Animals↗
PubMed1974

[Oogenesis in hydra. II. Cytophotometric determination of DNA concentration in the nuclei of somatic and sex cells].

During sexual reproduction in Hydra, interstitial cells in the female sex zone of the body (i-cells) undergo mitotic division and form a thickening in the epiderm. The proliferation of i-cells is accompanied by the increase of cytoplasm volume and by the appearance in the cytoplasm of a great number of membranous structures (rough endoplasmic reticulum, Golgi apparatus and mitochondria), enzymatic granules, lipid inclusions and glycogen. All cells of the epidermal thickening soon (in approximately twenty four hours) acquire the characteristics of typical phagocytes. However it is the cell situated inside the group of syncytially connected ones and adjacent to mesogloea that begins to grow rapidly and phagocytize surrounding cells. The cells of the epidermal thickening, though they are often given the name of oogonia, were found to have a tetraploid DNA content in their nuclei. The presence of four unseparated centrioles of equal size suggests that all preparatory processes for division were completed. A conclusion was drawn that cells of the epidermal thickening undergo premeiotic DNA synthesis prior to their phagocytizing by the growing oocyte and, thus, are oocytes themselves. The oogonial stage in Hydra coincides with the early period of mitotic reproduction of i-cells. The data obtained are discussed from the viewpoint of the formation of the accessory gonad apparatus.

Animals↗
PubMed1980

Temporal relationships between ovulation and defined changes in the concentration of plasma estradiol-17 beta, luteinizing hormone, follicle-stimulating hormone, and progesterone. I. Probit analysis. World Health Organization, Task Force on Methods for the Determination of the Fertile Period, Special Programme of Research, Development and Research Training in Human Reproduction.

One hundred seventy-seven women have been studied over the periovulatory period, in order to obtain detailed information on temporal relationships between ovulation and defined changes in the concentrations of estradiol-17 beta (E2), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and progesterone (P) in peripheral plasma. Serial samples of blood were taken, the surfaces of the ovaries were examined at laparotomy, and the mature follicle or corpus luteum was removed for histologic examination. The results in 107 cases fulfilled the criteria for statistical analysis, and in 78 the operation was performed after the follicle had ruptured. A probit analysis was undertaken with use of the proportion of women who had ovulated at a given time in relation to the interval from a defined rise or peak in the concentration of a circulating hormone. The median time intervals (in hours) from the hormonal event to ovulation and the 95% confidence limits of the estimates are as follows: 17 beta-estradiol--rise 82.5 (54.0 to 100.5), peak 24.0 (16.9 to 32.1); LH--rise 32.0 (23.6 to 38.2), peak 16.5 (9.5 to 23.0); FSH--rise 21.1 (14.1 to 30.9), peak 15.3 (8.1 to 21.7); progesterone--rise 7.8 (-12.5 to 15.9). From the statistical model for LH it was possible to estimate that ovulation in 90% of the cases had occurred between 16 (+/- 6) and 48 (+/- 6) hours after the first significant rise in the concentration of this hormone and between -3 (+/- 5) and 36 (+/- 5) hours after the peak. An examination of the individual results in every woman gave corresponding ranges of between 24 and 56 hours from the first significant rise in LH and between 8 and 40 hours after the peak. From a practical standpoint, the conclusion is that a defined rise in the concentration of circulating LH is the best indirect parameter of impending ovulation.

Adult↗
PubMed2003

Effect of acetyl salicylic acid in drinking water on reproductive performance of Japanese quail (Coturnix coturnix japonica).

The impact of acetyl salicylic add (ASA) on reproductive performance during periods of heat stress was studied in Japanese quail (Coturnix coturnix japonica). During a season when daily high temperatures averaged between 34 and 40 degrees C, four treatments each containing four replicates of five males and five females were given 0, 0.5, 1.0, or 1.5 g/L ASA in drinking water from 34 to 45 wk of age. At 39 wk of age control quail were lighter than quail fed ASA. Quail receiving 1.5 g/L ASA exhibited increased fertility, hatchability, and egg production and decreased late dead and total embryonic mortality. Early dead embryos, pips, chick weight, and egg weight were not different among treatments. The lumen of uterovaginal junction sperm host glands (UVJSHG) from control quail was apparently devoid of spermatozoa, whereas quail receiving 1.5 g/L ASA had the greatest apparent accumulation of spermatozoa. Control caudal infundibulum host glands (CPOI) were devoid of spermatozoa in contrast with CPOI from quail receiving ASA. Results show that UVJSHG lumens from quail receiving 1.5 g/L ASA had larger inside diameters than other treatment groups. However, the CPOI inside diameter and the outside diameters of both UVJSHG and CPOI were not affected by ASA. Adding 1.5 g/L ASA to the drinking water of quail under heat stress improved body weight, fertility, hatchability, embryonic mortality, egg production, egg specific gravity, and sperm storage capacity.

Animals↗
PubMed1975

Effects of stimuli emanating from the nest on the reproductive cycle in the ring dove. II: building during the pre-laying period.

The nest is a major focal point of the reproductive cycle in the ring dove (Streptopelia risoria). This study shows that the state of the nest is an important determinant of the type of nest-building exhibited. For example, birds faced with an empty nest bowl every day removed more material from dispensers and built more actively than did those allowed to construct nests normally. Conversely, those given completed nests were not very active, but were more efficient in using the little they removed from the dispensers and showed a reversal of sex roles in building. The relations between nest-building and egg-laying, and between male and the female are discussed.

Animals↗
PubMed2002

The relationship between body condition, leptin, and reproductive and hormonal characteristics of mares during the seasonal anovulatory period.

An experiment was conducted to determine the effects of high vs low body condition scores (BCS) produced by restricted feeding on reproductive characteristics, hormonal secretion, and leptin concentrations in mares during the autumnal transition and winter anovulatory period. Mares with BCS of 6.5 to 8.0 were maintained on pasture and/or grass hay, and starting in September, were full fed or restricted to produce BCS of 7.5 to 8.5 (high) or 3.0 to 3.5 (low) by December. All but one mare with high BCS continued to ovulate or have follicular activity during the winter, whereas mares with low BCS went reproductively quiescent. Plasma leptin concentrations varied widely before the onset of restriction, even though all mares were in good body condition. During the experiment, leptin concentrations gradually decreased (P < 0.0001) over time in both groups, but were higher (P < 0.009) in mares with high vs low BCS after 6 wk of restriction, regardless of initial concentration. No differences (P > 0.1) between groups were detected for plasma concentrations of LH, FSH, TSH, GH, glucose, or insulin in samples collected weekly; in contrast, plasma prolactin concentrations were higher (P < 0.02) in mares with high BCS, but also decreased over time (P < 0.008). Plasma IGF-I concentrations tended (P = 0.1) to be greater in mares with high vs low BCS. The prolactin response to sulpiride injection on January 7 did not differ (P > 0.1) between groups. During 12 h of frequent blood sampling on January 12, LH concentrations were higher (P < 0.0001), whereas GH concentrations (P < 0.0001) and response to secretagogue (EP51389; P < 0.03) were lower in mares with high BCS. On January 19, the LH response to GnRH was higher (P < 0.02) in mares with high BCS; the prolactin response to TRH also was higher (P < 0.01) in mares with high BCS. In conclusion, nutrient restriction resulting in low BCS in mares resulted in a profound seasonal anovulatory period that was accompanied by lower leptin, IGF-I, and prolactin concentrations. All but one mare with high BCS continued to cycle throughout the winter or had significant follicular activity on the ovaries. Although leptin concentrations on average are very low in mares with low BCS and higher in well-fed mares, there is a wide variation in concentrations among well-fed mares, indicating that some other factor(s) may determine leptin concentrations under conditions of high BCS.

Animals↗
PubMed2006

Assessment of reproductive parameters in female Dwarf goat (Capra hircus) on the basis of progesterone profiles.

A study was undertaken to look into the reproductive performance of female Dwarf goats reared under traditional conditions at NIAB Farm, Faisalabad, Pakistan. The serum progesterone profile was used to monitor various reproductive parameters (length of postpartum period, resumption of cyclicity, gestation period, prepartum period, parturition) in two lots of goats. Litter size, birth weight of kids and kidding interval were also observed. Most of the animals conceived within 15-59 days of postpartum period. All the does conceived at first or second estrus. During gestation period, higher levels of progesterone were maintained with wide variations falling in the range of 3-13 ng ml(-1). However, a few days before parturition a decline was noticed at 6+/-0.9 days and it reached to the basal level of 0.1 ng ml(-1) after the completion of parturition process. The length of gestation period was found to be 145.8+/-5 days in the first lot and 145.2+/-4 days in the second lot. A very short kidding interval (203.7+/-46 days) and considerably bigger litter size (1.8+/-0.8) was observed. All the parturitions were normal and a considerable weight gain (8.2+/-0.3 kg) of mothers was recorded during pregnancy. The initial birth weight of kids was averaged as 2.1+/-0.5 kg in the first and 1.6+/-0.2 kg in the second lot. It was concluded that Dwarf goat has short gestation length, postpartum period and kidding interval along with multiple births being common. Due to these factors, its reproductive efficiency can be exploited for efficient goat meat production.

Animals↗