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PubMed1989

[The optimal service period in bitches].

The fertile period in bitches as estimated from the findings reported in the literature is discussed. Fertile periods of oocytes and spermatozoa are examined extensively. The period of ovulation is found to be more closely associated with hormonal changes than it is with symptoms of oestrus. This period occurs when the concentration of progesterone in the blood increases to a level higher than (16 nmol/l). Service one and a half days after the ovulation period results in high pregnancy rates.

Animals↗
PubMed1989

An evaluation of the BIOSELF 110 fertility indicator.

The BIOSELF 110 is a hand-held, non-invasive electronic instrument that measures basal body temperature and cycle length, and automatically identifies the fertile and infertile phases of the menstrual cycle with flashing red light and green light signals, respectively. The device was evaluated in 77 cycles from 33 ovulatory women in Kuala Lumpur, Malaysia. Ultrasound monitoring of maximum follicular diameter (MFD) and urinary LH measurements with Ovustick were used as reference methods to estimate the time of ovulation and the fertile period. Based on the MFD day, the BIOSELF correctly identified the entire fertile period, and at least four fertile days, in 89% and 94% of the cycles studied, respectively. The mean duration of the fertile period as determined by the number of flashing red light days was 11.0 days (SD 2.9). The device correctly identified the onset of the postovulatory infertile phase in 94% of cycles, with a mean duration of about 10 (green light) days. The results were similar using the LH peak day as the reference method. The mean interval from the onset of the fertile period (first flashing red light day) to the MFD day was 6.9 days (SD 2.6), and from the MFD day to the end of the fertile period, 3.1 days (SD 2.2). The BIOSELF 110 showed itself to be a reliable device for identifying the fertile and infertile phases of the menstrual cycle and, thus, should be a useful aid for couples seeking pregnancy. Prospective clinical trials are underway to assess the contraceptive effectiveness of the device.

Adult↗
PubMed1998

Copulatory behaviour and paternity in the American kestrel: the adaptive significance of frequent copulations.

The adaptive significance of repeated withinpair copulations is not well understood. We analysed the copulatory behaviour of 16 pairs of solitary-nesting American kestrels, Falco sparverius, in southern Quebec (Canada), and the achieved reproductive success (paternity) of 21 kestrel families determined by DNA fingerprinting, in terms of four hypotheses. (1) The paternity assurance hypothesis, which suggests that males copulate frequently to avoid being cuckolded, was rejected because there were few extrapair copulation attempts (<1% of all copulations observed), withinpair copulations were not timed during the fertile period and mate attendance did not increase as the fertile period approached. (2) The immediate material benefits hypothesis, which suggests that females trade copulations for food, was refuted because copulations most often occurred without food transfers, especially outside the fertile period. (3) The female mate guarding of males hypothesis, which suggests that females distract their mates from other mating opportunities by copulating frequently, was rejected because extrapair copulation attempts were infrequent, male and female solicitation frequencies were similar and females did not differ in the timing or frequency of solicitations. (4) The mate assessment hypothesis, which suggests that assessment of mate quality is mediated via copulation, most closely predicted the behaviour observed since withinpair copulations were frequent outside the fertile period and at pair formation, males and females solicited similar numbers of copulations and pairs did not differ significantly in solicitation or copulation frequency. In line with this hypothesis we found that only one brood was extrapair, probably the result of mate replacement.Copyright 1998 The Association for the Study of Animal Behaviour

Journal Article↗
PubMed1992

Egg production of Clonorchis sinensis in different strains of inbred mice.

In order to compare the intraspecific variation in host-parasite relationship of Clonorchis sinensis, six strains of inbred mice, ICR, DDY, GPC, BALB/c, nude and DS, were infected orally with 20 metacercariae of C. sinensis. The biologic incubation period of C. sinensis was the shortest in DDY mice, 21.2 days in average, followed by GPC 21.4, BALB/c and DS 23.2, ICR and nude 23.4 days, respectively. The fertile period of the fluke was also the longest in the DDY strain, 164 days on average, followed by GPC 132, BALB/c 97, nude 37, DS 32 and ICR 28 days. The egg-laying capacity of the fluke in DDY and GPC was relatively high and stable compared with the other four strains of mice. It was found that there are intraspecific variations in biologic incubation period, fertile period, and fecundity of C. sinensis. The DDY mouse is likely to be the most suitable experimental animal among the six strains of the mice tested.

Animals↗
PubMed1986

The desmoid syndrome. New aspects in the cause, pathogenesis and treatment of the desmoid tumor.

Based on a detailed clinical and laboratory investigation of 89 patients with histologically verified desmoid tumor and the pertinent medical literature, we have reviewed the etiologic factors, clinical characteristics, and results of treatment of this rare disorder. The incidence of the tumor in the Finnish population is low, 2.4 to 4.3 new cases per 10(6) inhabitants per year. The age distribution profile demonstrated four distinct peak periods: the juvenile period, the fertile period, the middle-age period and the old-age period. The juvenile desmoid tumor is an extraabdominal tumor found in young girls, the fertile variety is an abdominal tumor found in women, the middle age variety is also overwhelmingly abdominal but the sex ratio approaches equality, whereas in the old age group, both abdominal and extraabdominal tumors are equally frequent and the sex ratio is equal. In all male patients, the growth rate was low. A low growth rate was also recorded in young girls. A growth rate of twice that speed was seen in fertile women and four times that speed in the middle age group. In the old age group, a low growth rate, equal to that of male patients, was a rule. The fertile female patients with desmoid tumor had a significant predisposition to estrogen dominance and deviation from progesterone dominance. The direct relationship of the growth rate to the level of endogenous estrogen in the female patients and the demonstration of significant amounts of estradiol but not progesterone receptors in the tumor cytosol further suggest that the growth rate of desmoid tumor is regulated by steroid sex hormones. A significant number of patients with an abdominal desmoid tumor had a history of surgical trauma in the region of subsequent tumor growth. A very high number of the patients demonstrated multiple minor malformations of the bony skeleton. An increased frequency of these malformations was also recorded in the families of the patients and the distribution of the malformations among the family members was compatible with an autosomally dominant pattern of inheritance. After operation, the frequency of recurrence was not statistically different, regardless of whether the tumor was completely removed or not. A combination of operation and radiotherapy did not reduce the frequency of recurrences; in fact, it doubled it.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed2001

A sensitivity analysis of the Bongaarts-Feeney method for adjusting bias in observed period total fertility rates.

Our sensitivity analysis shows that the adjusted TFR'(t) using the formula of Bongaarts and Feeney (1998), which assumes an invariant shape for the fertility schedule, usually does not differ significantly from an adjusted TFR"(t) that allows the shape of the fertility schedule to change at a constant annual rate. Because annual changes in the shape of the fertility schedules often are approximately constant except in abnormal conditions, the Bongaarts-Feeney (B-F) method is generally robust for producing reasonable estimates of the adjusted TFR'(t). The adjusted TFR'(t) neither represents any real cohort experiences from the past nor forecasts any future trend. It merely provides an improved reading of the period fertility measure, which reduces the tempo distortion.

Analysis of Variance↗
PubMed2003

Ecological constraints on extra-pair paternity in the bluethroat.

The mating system of the bluethroat (Luscinia s. svecica) involves a high level of sperm competition, and consequently a high frequency of extra-pair paternity (EPP). There is considerable variation in the frequency of EPP. Over the course of ten study years in a population in Norway, the frequency has fluctuated between 7% and 33% of young, and 8% and 76% of broods. In this paper, we address the issue of whether ecological factors can explain some of the variation in EPP between years and broods. Factors include breeding density, breeding synchrony and two meteorological variables (ambient temperature and precipitation) during the period of peak female fertility. There were no significant relationships between annual averages of the four variables and the annual level of EPP, but the statistical power of these tests was low, due to a restricted sample (n=10 years). Focussing on individual broods, none of the factors had significant effects when including all broods in the analyses (including those with zero EPP). When limiting the analyses to broods with one or more extra-pair offspring, morning temperature had a significant effect on the frequency of EPP. When the temperature was low during the peak of the fertile period, EPP occurred less frequently. Male extra-pair behaviour was not generally constrained by synchrony between the fertile periods of the social mate and the extra-pair mate, but for a subgroup of males ("unattractive males") there appeared to be a trade-off between mate guarding and pursuing extra-pair copulations. Our results indicate that ecological conditions have no influence on whether or not a brood will contain extra-pair offspring, but when EPP does occur, its frequency is influenced by air temperature. Possibly, there is a causal relationship between weather conditions and the frequency of extra-pair encounters in this species. The breeding season is initiated at a phenologically early stage, when large parts of the territories are still covered with snow, and cold weather conditions may force the birds to devote most of their time to maintenance and thereby constrain sexual activities.

Animals↗
PubMed1997

Developmental toxicity induced during early stages of mammalian embryogenesis.

Both a conceptual and a practical borderland between teratology and mutagenesis is early embryogenesis, the period between fertilization and gastrulation. Radiation and a variety of chemicals adversely affect the early conceptus leading to in utero mortality and malformations. The post-fertilization period of susceptibility differs from exposures of gametes, the later producing excessive pre- and peri-implantational death and low rates of fetal anomalies predominated by growth retardation. In contrast mutagen exposure of the zygote induces peri-implantational death, pan-gestational death and fetal anomalies predominated by hydrops, abdominal wall defects, and eye aberrations. The mechanism for this pathology remains unclear. These same agents produce a broader range of phenotypic anomalies during the remainder of pre-gastrulation development with anomalies overlapping those induced during organogenesis. Retinoic acid and 5-azacytidine administered prior to gastrulation produce novel malformation syndromes indicative of gene expression modification. The rates and types of defects from mutagen treatment of both gametes and the early conceptus contrast with those resulting from embryonic treatment during organogenesis, and the mechanisms are likely to differ. The pre-gastrulation period has not been explored to the extent reported during gametogenesis or organogenesis. Pre-gastrulation teratology is a new area of investigation with relevance both to reproductive toxicology and to mammalian developmental biology.

Abnormalities, Drug-Induced↗
PubMedDate not supplied

Prediction of ovulation with the assessment of LH and the E1G/P2G ratio in urinary samples.

The aim of this study is to evaluate the efficacy of two immuno-enzymatic urinary tests (Clearpan for LH secretion and Oveia for E1 G/P2G ratio) in the study of the oophorogenous function, in the prediction of ovulation, and in the recognition of the period of fertility. Both tests are very promising for a retrospective evaluation of the oophorogenous function; for the prediction of ovulation in spontaneous cycle, the Clearpan test is certainly preferable; in the monitoring of the ovulation in the cycles stimulated with post-menopausal gonadotropins, the Oveia test finds better application when accompanied by ultrasonographic evaluation; in the recognition of the fertile period, both tests shown a certain degree of doubt, so they cannot be used with surety.

Adult↗
PubMed1988

Analysis of the outcome of 124 pregnancies produced during NFP.

The outcome of 124 pregnancies produced during the use of CM (Billings) of NFP is analyzed. The spontaneous abortion rate was 8%. The women who became pregnant in the less fertile period (+/- 3 days from peak day) presented a higher rate of spontaneous abortions (13.9%) than the women who became pregnant during the most fertile period (peak day +/- 2 days), who presented a 4.3% spontaneous abortion rate. Among the 115 living infants (one twin pregnancy) there was one congenital malformation (0.8%), a cleft palate. The sex ratio of the infants was 0.59 (48 females and 67 males), which is not significantly different from the 0.51 sex ratio expected. When conception occurred during the most fertile period, the sex ratio was 0.37, in contrast to the sex ratio of 0.76 when conception occurred in the less fertile period; this is a highly significant difference (P less than 01).

Abortion, Spontaneous↗
PubMed1998

No relationship between territory size and the risk of cuckoldry in birds.

It has been suggested that male birds adjust their territory size in order to prevent potential intruders from gaining extra-pair copulations. The risk of cuckoldry is supposed to be highest when the distance between a female and the neighbouring males is shortest. This paper describes the variation in territory size of the chiffchaff, Phylloscopus collybita, in relation to the breeding cycle. Contrary to the risk of cuckoldry hypothesis, chiffchaff territories were larger prior to the fertile period of the females and at a minimal size during the fertile period. A review of the literature shows little, if any, evidence of a peak in territory size during the fertile period of the females for most species studied. It is suggested that territoriality is in need of an operational definition. Without such a definition, it is difficult to make and test predictions about the adaptive basis of variation in territory size. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2000

Suppression subtractive hybridization identifies genes expressed in oviduct during mouse preimplantation period.

Fertilization and development of mouse embryos occur in the ampullae of oviduct. Various growth factors and embryotrophic factors produced by the oviductal cells have been demonstrated to enhance embryo development in vitro. As a step towards understanding the genetic changes of mouse oviduct during mouse embryos preimplantation period, we adopted suppression subtractive hybridization (SSH) to establish four subtracted cDNA libraries to identify (1) oviduct-expressing genes, and (2) genes that may support embryo development in vivo. Using this method, we isolated 82, 88, 99, and 109 clones from four mouse libraries prepared from 0 (day 0), 24 (day 1), 48 (day 2), and 72 h (day 3) post-human chorionic gonadotropin (hCG) treated mice. Reverse dot-blot analysis confirmed that 25 (day 0), 24 (day 1), 40 (day 2), and 29 (day 3) clones were highly expressed in mouse oviduct when compared to other tissues. DNA sequence analysis identified genes encoding mouse oviduct-specific glycoprotein (MOGP), actin-binding protein 280, and several viral genes. Northern analysis confirmed that the genes were mainly expressed in oviduct, with some viral genes also expressed in uterus. About 9% of these oviduct expressing clones (11/118) were novel. We further demonstrated that one of the novel clones ODEG0-17 was expressed in the oviduct during early embryo preimplantation period and rarely in other tissues by RT-PCR. Our results show that SSH is a powerful method applicable to identifying tissue-specific transcripts on fertilization and development.

Animals↗
PubMed1975

[Influence of the biological activity of substances on the puerperal period and fertility of cows].

Experiments were carried out to shorten the service period and increase the conception rate in 304 cows under productional conditions with the use of drugs, hormonal means, and preparations producing unspecific effects on the reticulo-endothelial system, immediately after giving birth. It was found that: the parenteral treatment of cows one to three hours following calving with 200,000 IU vitestrol and 15-20 IU hypophysin, on the one hand, and (after the removal of the placenta) the infusion into the uterus of 1-2 g chloramphenicol, 15 g ac. citricum of Na citricum and 0.2 g pilocarpinum hydrochloricum, emulsified in 20-30 cu. cm oil emulsion of vitamins A, D3 and E, and the injection by the fifth day after calving of 30-40 cu. cm of tissue emulsion prepared after Filatov with the use of bovine liver or swine embryos, on the other, decreased the "independences" period with 7.01 days, the service period -- with 27.50 days, and the index of insemination -- with 0.60. At the same time the conception rate resulting from the first insemination rose by 25.20 per cent as compared to the untreated animals. The prophylactic veterinary treatment of cows thus contributed in decreasing the cases of retentio secundinarum after calving by 6.2 per cent, and the cases of acute endometritis -- by 12.9 per cent. Treatment of cows after calving, using hormonal, chemiotherapeutic, and biogenic stimulators, contributes, along with other means to raise the annual number of calves per 100 cows up to ten.

Animals↗
PubMed2005

Reproductive endocrinology of wild female chimpanzees (Pan troglodytes schweinfurthii): methodological considerations and the role of hormones in sex and conception.

Fecal and urine samples were collected from 81 female East African chimpanzees (Pan troglodytes schweinfurthii) in three major study populations in Gombe National Park, Tanzania, and Budongo Forest Reserve and Kibale National Park, Uganda. In this study I evaluated issues related to sample storage and assay reliability, and used these methods to investigate the significance of ovarian hormone levels in terms of conception success and sexual behavior. Drying of feces proved to be an effective technique and resulted in hormonal concentrations that were significantly correlated with concentrations in frozen feces. Estimates of ovarian steroid production based on urine and fecal sampling were significantly correlated with each other. The ovarian cycle profiles obtained, which were aligned relative to sexual swelling detumescence, corroborate previous findings in wild west African chimpanzees [Deschner et al., Animal Behaviour 66:551-560, 2003] in suggesting that the fertile period is limited to the last week of tumescence, but that ovulatory timing is not as precise as previously thought. A comparison across cycles confirmed the hypothesis that higher ovarian steroid levels are associated with an increased probability of conception. Females that did conceive with relatively low hormone levels had poor reproductive outcomes. Sexual behavior was tied to the probability of conception both within and across cycles. Copulatory activity within cycles closely followed the estrogen profile and was timed to coincide, on average, with the peak fertile period of females. Further, rates of copulation were significantly higher during the fertile periods of cycles that led to conception than those that did not.

Animals↗
PubMed1999

Seasonal patterns of singing in the willow warbler: evidence against the fertility announcement hypothesis.

Males of many bird species use a variety of behaviour patterns that reduce their chances of being cuckolded. The 'fertility announcement' hypothesis (Møller 1991, American Naturalist, 138, 994-1014) proposes that song might be one such paternity guard. According to this hypothesis, paired males would announce their female's fertile status by singing. This has been interpreted as an honest signalling, evolutionarily stable strategy. Contrary to the predictions of this hypothesis, male willow warblers, Phylloscopus trochilus, sang very little when females were fertile. Intrusions by other males in the fertile period were not less common when males sang at higher rates. Mate guarding and singing are best interpreted as two conflicting behaviours during this period, the former being directed to the fertile female and the latter to attracting a second female, or an extrapair female. A survey of recent studies suggests that, in most passerine species studied, males do not sing during the fertile period of their females. The different conclusions of Møller (1991) are probably due to his use of population-wide estimates of the timing of singing behaviour and egg laying. Breeding asynchronies within populations would be responsible for the apparent matching between the peaks of singing activity and fertility. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2005

Selection for high gamete encounter rates explains the evolution of anisogamy using plausible assumptions about size relationships of swimming speed and duration.

A previous general model describing physical constraints on gamete encounter rates was modified to incorporate assumptions that increased size causes decreased swimming speed and increased fertile period (or other proportional enhancement to gamete fertility). The analysis indicates that with moderately strong size dependence of fertile period and a range of speed dependencies, selection for high encounter rates pressures mating systems that develop any heritable difference in size between the gametes of different mating types to exaggerate the difference and evolve from isogamy to anisogamy. The smaller gamete has an optimal size, but the larger faces continuing selection for increased size. This continues to a size that is estimated to be sufficient to make pheromone production of sperm attractants practical. This mechanism then bridges the missing link between isogametes and oogamy in a previous analysis of the effectiveness of pheromones in explaining the success of male-female mating systems. The evolution and success of anisogamy and oogamy can be explained solely on the basis of physical effects on the encounter process.

Animals↗
PubMed1992

Natural menopause, oophorectomy, hysterectomy and the risk of osteoarthritis of the dip joints.

The purpose of this study was to determine whether postmenopausal women have an increased risk of developing radiological osteoarthritis (ROA), bony enlargement or Heberden's nodes of the distal interphalangeal (DIP) joints. Secondly, the effects of the duration of the postmenopausal period, age at menopause or duration of the fertile period on the occurrence of DIP-OA were studied. Data from a population survey were used and 143 postmenopausal women with a natural menopause, 53 with a hysterectomy and 75 with a hysterectomy and bilateral oophorectomy were compared with 374 premenopausal women. There was no significant association of these postmenopausal states with ROA, bony swelling or Heberden's nodes. Age adjusted odds ratios and 95% confidence intervals were 1.14 (0.68-1.91), 1.30 (0.72-2.35), 1.92 (0.77-4.76), respectively for the women with a natural menopause. After adjusting for age there was a positive relationship of Heberden's nodes with age at menopause and duration of the fertile period for women with a natural menopause.

Aging↗
PubMed1998

[Prospective study of the efficacity of a recent symptomatic-thermal method of natural family planning].

UNLABELLED: A Belgian pilot-study conducted in the framework of the prospective European multi-center study (University of Düsseldorf) tried to establish the use-effectiveness (a sine qua non condition for its acceptance in Europe) of natural family planning. MATERIAL AND METHODS: 84 participants provided data (sympto-thermal chart and related information) on 1,750 cycles where family planning intention was to avoid a pregnancy. The average age of the women was 32 years. A contraceptive method (mainly oral contraceptives) was employed previously by 61% of them. The sympto-thermal method used by the test group highlights the beginning and the end of the menstrual cycle's fertile period by a double check. As to the start of the fertile period, the criteria are: a calculation on the length of the previous twelve cycles and the first sign of mucus at either the vulva or the cervix. Indicators of the end of this phase are: the third day of high temperature and the fourth evening after either the peak mucus day or the peak cervix day. 75% of the women involved generally use the cervical auto-palpation. RESULTS: No method failure at all has been detected. Two unplanned pregnancies occurred due to user failure. The total Pearl index for the study was 1.4. When examining only those cycles (85% of the reported cycles) where no protected sexual intercourse occurred during the fertile phase, practical efficacy of the method analysed was 1.8 according to Pearl index. Furthermore, taking into account protected and unprotected sexual intercourse occurred during the fertile phase, we observed that sexual abstinence was practised during the "risk" period of 75% of the cycles. CONCLUSIONS: The results of this test study demonstrate the practical efficiency of a modern natural family planning method. The high level of cycles during which periodic abstinence was employed testify to the acceptability of the method used.

Adult↗