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PubMed1990

Effects of sublethal dosages of Abate upon adult fecundity and longevity of Aedes aegypti.

Sublethal concentrations of Abate (temephos) were applied to F2 generation Aedes aegypti larvae, and fecundity and longevity were recorded in the emerged adults. Females exposed to Abate oviposited only in the first 2 gonotrophic cycles, meanwhile control females laid a few eggs after taking the third blood meal. Dosages of 0.009, 0.013 and 0.015 mg/liter of Abate decreased the mean egg production per gonotrophic cycle 37, 47 and 69%, respectively, in relation to the control. Females that were exposed as larvae to Abate lived longer than the control females.

Aedes↗
PubMed1992

Decreased fecundability in Hutterite couples sharing HLA-DR.

To study the effects of parental HLA sharing on pregnancy outcome, we initiated population-based studies in the Hutterites. We previously reported longer intervals from marriage to each birth among couples sharing HLA, particularly HLA-DR. In the present report, we present the results of a prospective, 5-year study of fecundability and fetal loss rates in this population. Between April 1986 and April 1991, 154 pregnancies were observed in 104 couples. The median number of months of unprotected intercourse to a positive pregnancy test was significantly longer among couples sharing HLA-DR who stopped nursing prior to the first menses as compared with couples not sharing HLA-DR who stopped nursing prior to the first menses (5.1 vs. 2.0 mo, respectively; P = .016). Fetal loss rates were increased among couples sharing HLA-B as compared with couples not sharing HLA-B (.23 vs. .12, respectively; P = .041, adjusted for age, gravidity, and kinship). These data suggest that our earlier observations of increased birth interval lengths among Hutterite couples sharing HLA were predominantly due to longer intervals until a clinical pregnancy among couples sharing HLA-DR and, to a lesser degree, were due to increased fetal loss rates among couples sharing HLA-B.

Abortion, Spontaneous↗
PubMed1990

Parity, fecundity and body size of Mansonia dyari in Florida.

Seasonal trends in reproductive performance and size were examined among female Mansonia dyari. The incidence of parity ranged between 6.9 and 58.1% and averaged 22.5% during an 8-month interval, with 4 peaks in parous rate believed to follow periods of emergence. Parous rates were positively correlated with wing lengths, indicating size-dependent survivorship. Wing lengths were highest in the winter and early spring, decreased to a minimum at the end of summer, and increased in the autumn, showing negative correlations with ambient temperatures recorded prior to adult capture. Female biomasses and fecundities were positively correlated with wing lengths, and their mean values varied significantly among sample dates. Egg development in Ma. dyari was completed by 5.4 days post blood meal at 26 degrees C and 7.6 days at 20 degrees C. No evidence for autogeny was observed.

Animals↗
PubMedDate not supplied

New developments in the treatment of male sub-fertility by means of assisted fecundation techniques.

In the second bimester of 1990 we have performed IVF/ET in a group of patients who had previously been excluded from the IVF/ET programme for severe dyspermia and negative Pellet Swim-up Test (PST). This group consisted of 101 cases of whom 38 underwent semen treatment with Centrifugation on a Discontinuous Percoll Gradient (CDPG) and 63 with Pellet Swim-up (PS); the control group was made up of 31 normospermic patients where the semen was treated by PS. Furthermore, in the same period, we performed Tubal Embryo Stage Transfer (TEST) on 5 normospermic and on 2 dyspermic cases, as well as Zygote Intra-Fallopian Tubal Transfer (ZIFT) on 2 normospermic patients. In all these cases the sperm was always treated with PS. We obtained disappointing IVF/ET results in the dyspermic patients with negative PST where the semen was treated with PS, with only one pregnancy (pregnancy rate 1.6% per patient). Unexpected results were obtained in cases of severe dyspermia where the semen was treated with CDPG (5 pregnancies out of 38 cases; pregnancy rate 13.1% per patient) (chi square = 7.03, p 0.01). We obtained remarkable Test results: 4 pregnancies out of 5 cases of unexplained infertility and one pregnancy out of 2 cases of dyspermia. Moreover we obtained one pregnancy in the two ZIFT's performed. The use of CDPG, possibly associated with Test, will open new horizons in the treatment of dyspermic patients by means of assisted fecundation techniques.

Humans↗
PubMed1990

Alterations in the longevity and fecundity of adult Trichinella pseudospiralis related to method of isolation of infective larvae.

The infectivity of Trichinella pseudospiralis infective larvae was reduced significantly following exposure to low pH or a combination of 1% pepsin at low pH compared to that for larvae isolated in phosphate-buffered saline (PBS) at pH 7.0. Reduction of host gastric pH by administration to mice of sodium bicarbonate solution in PBS was accompanied by an increase in the infectivity of larvae isolated in 1% pepsin/HCl (P/HCl) compared to that for worms inoculated into hosts given PBS alone. Fewer adult worms developing from larvae isolated in P/HCl became established in the host small bowel than was seen with larvae isolated in PBS; moreover, the fecundity in vitro of adult worms developing from P/HCl-isolated larvae was reduced below that for adults developing from larvae isolated from host muscle in PBS. More adult worms were recovered following infection of immune hosts with PBS-isolated larvae than were recovered from immune mice challenged with larvae isolated in P/HCl. Similar findings were observed in mice immunized by infection with Trichinella spiralis and challenged with T. pseudospiralis larvae isolated in either P/HCl or PBS. Immunization of mice with T. pseudospiralis larvae isolated by either method and challenged with larvae of T. spiralis resulted in recovery of similar percentages of the challenge inoculum.

Animals↗
PubMed1990

Seasonal variation in fertility, fecundity and litter sex ratio in laboratory and wild stocks of house mice (Mus domesticus)

Data compilations were made for three parameters pertaining to reproduction in a domestic strain (14 years) and a wild stock (4 years) of commensal house mice: (a) the percentage of females mated that produced litters; (b) the average number of pups per litter; and (c) the sex ratio of the pups in the litters. Fecundity and fertility varied seasonally in both domestic and wild mice. More females become pregnant and litter sizes were larger in the spring, summer, and fall months than during the winter season. Sex ratios also varied seasonally with more male biased litters produced during the 4 winter months. There appear to be seasonal shifts in productivity for both stocks of mice and these seasonal trends have not been altered by domestication under laboratory conditions. In spite of the fact that house mice are generally opportunistic, it is possible that there has been selection in the mice for shifting rates of production in relation to the best seasons of the year in terms of climate and resource availability. The higher production of males during summer months may be geared toward greater success in dispersal at that season and a higher probability that the males can find a territory and mate successfully in summer rather than winter. These results have potential implications for animal breeders and for those who maintain mouse colonies to produce animals for scientific investigations.

Animal Husbandry↗
PubMed1990

Estimation of fecundic life span of Wuchereria bancrofti from longitudinal study of human infection in an endemic area of Pondicherry (south India).

The fecundic life span of adult female W. bancrofti was estimated by longitudinal study of microfilaraemia in a cohort of population (7,525) in Pondicherry. The estimation was based on a deterministic model, using the rate of loss in infection. The life span of the parasite was 10.2 yr without chemotherapy, while it was reduced to 5.3 yr following diethyl-carbamazine therapy. The analysis of mean microfilarial counts in microfilaraemic persons without chemotherapy indicates that the rate of production of microfilaria by the adult female is stable at least for a period of five years.

Adolescent↗
PubMed1988

Lack of effect of unmated schistosomes on the fecundity of mated worm pairs.

An imbalance between the numbers of male and female worms had no significant effect upon the fecundity of Schistosoma mansoni in rhesus monkeys or upon the number of S. mansoni eggs in the tissues of infected persons or mice. The number of S. japonicum eggs in the tissues of infected rabbits was similarly unaffected by disproportion between worm genders.

Animals↗
PubMed1987

Laboratory investigations on the survival and fecundity of Phlebotomus duboscqi (Diptera, Psychodidae), a vector of Leishmania major in Kenya.

The gonotrophic cycle, survival and reproductive potential of adult female Phlebotomus duboscqi, a vector of Leishmania major in Baringo District, Kenya was investigated in the laboratory. The sandflies were fed on hamster and apples as a sugar source and were placed in vials for oviposition. The feeding and care for oviposition was repeated for as long as the flies lived. The longest period P. duboscqi survived after taking the first blood meal was 45 days. The flies completed up to eight gonotropic cycles resulting into a very high fecundity rate. The implications of this in relation to disease transmission by P. duboscqi is discussed.

Animals↗
PubMed1985

[The fecundity of selachian fishes].

From some data about species from Tunisian coasts the author proposes method for study and evolution of fecundity of oviparous and viviparous Selachians Fishes.

Animals↗
PubMed1979

Effect of Schistosoma mansoni infection on fecundity and perivitelline fluid composition in Biomphalaria glabrata.

Egg production in the snail, Biomphalaria glabrata, infected with Schistosoma mansoni declined on day 23 postinfection, and was significantly lower than uninfected control snails by day 28 and thereafter. Protein and galactogen content of eggs produced by infected snails did not change during the period of reduced fecundity. This suggests that decreased hemolymph nutrient levels (rather than depleted albumen gland reserves) are responsible for inhibition of snail egg production. Growth rates of infected and uninfected snails were indistinguishable from days 14 through 35 postinfection. The hatching success of eggs produced by infected snails decreased slightly beginning at day 21 postinfection.

Animals↗
PubMed1981

DDT-resistant Culex quinquefasciatus: the effect of DDT on the mosquito's size, fecundity and survival.

Resistant strains of Culex quinquefasciatus were selected in the larval stage by exposure to sublethal doses of DDT. The size, body weight and fecundity of DDT-resistant mosquitoes were significantly decreased. There was no significant difference between the longevity of females in the original strain and the DDT selected strains, however, there was a significant difference in the males of the DDT-resistant strains than those of the original strain.

Animals↗
PubMedDate not supplied

[Effects of prenatal alcohol consumption upon fecundity, natality, growth, vaginal opening and sexual cycle in the rat (author's transl)].

The purpose of this study was to investigate the action of prenatal alcohol consumption upon offspring and sexual maturity parameters on a rat strain which, for several years, drank only a brandy/water solution. With regard to fecundity and number of pups our results show no variation, while weight, vaginal opening, and sexual cycle are severely affected by alcohol intake. Possible alterations upon offspring due to chronic prenatal alcohol intake are examined.

Animals↗
PubMed1980

[The concept of fecundability in the etiologic, diagnostic and therapeutic approach to infertility (authors' transl)].

The infertility of a couple is most often attributable not to sterility but rather to subfertility in either one or both of the partners. Accordingly, the study of fertility in couples must be quantitative. Fertility can be appreciated by different indices; the most common being the fecundability, which is the probability (P) of a couple conceiving in a given menstrual cycle. It is a "risk", a concept of acknowledged value in public health. The standard epidemiological methods have led to the identification of its mean value which is of the order of 25% in our countries for young couples. It varies greatly from one couple to an other and with the numerous male and female factors on which it depends. The probability of couple obtaining a pregnancy seems to be the result of a lottery which recommences at each cycle with a probability of success P: a single formula shows how this probability increases both with P and with time. Thus, only by taking into consideration simultaneously male fertility, female fertility as well as time, an essential factor that is too often forgotten, is one able to rationally approach the etiology, diagnosis and therapeutics in case of infertility.

Adolescent↗
PubMedDate not supplied

Adaptation to pregnancy and motherhood among subfecund and fecund primiparous women.

OBJECTIVE: To examine the effects of infertility treatment on women's ability to adapt to pregnancy and motherhood. METHODS: Fecund (n = 261) and subfecund (n = 103) primiparous women receiving obstetrical care in southeastern Michigan participated in this descriptive, correlational, prospective study. The subjects completed Lederman's Pre-Natal Self-Evaluation questionnaire during the third trimester of pregnancy and Lederman's Postpartum Self-Evaluation questionnaire during the first postpartum appointment. FINDINGS: Mean scores showed that the two groups of women were not significantly different with either adaptation to pregnancy or motherhood. CONCLUSIONS & IMPLICATIONS FOR NURSING: Although subfecund women may experience stress in order to achieve a pregnancy, there do not appear to be any latent effects of this stress on their ability to adapt to pregnancy or motherhood.

Adaptation, Psychological↗
PubMed1995

Development of the sheep ovary during fetal and early neonatal life and the effect of fecundity genes.

In female sheep fetuses, the mesonephros and genital ridge can be identified at days 20 and 23 of gestation (term = 145 days), respectively. Moreover oogonia can be observed at the genital ridge from as early as day 23. Around day 55 of gestation, some germ cells enter meiosis coincident with the arrival of mesonephric-derived somatic cells (i.e. the rete ovarii). From day 75, 100, 120 and 135 of gestation, primordial (one layer of flattened granulosa cells), primary (one complete layer of cuboidal granulosa cells; early preantral), secondary (preantral) and tertiary (antral) follicles, respectively, develop within the innermost regions of the ovarian cortex. During the early neonatal period highly variable numbers of antral follicles may be present. After examination of Booroola fetuses from day 28 of gestation, it seems that the FecBB gene is associated with retarded development of the heart (day 28) mesonephros (days 30-40) and from day 30 to early neonatal life, the ovary. With respect to the ovary, fewer oogonia (days 30-40), primordial follicles (day 75-90) and growing follicles (day 120 to 6 weeks after birth) have been observed in females carrying the FecBB gene. By contrast, the FecBB gene is not associated with differences in plasma gonadotrophin or immunoreactive inhibin until early neonatal life. In Inverdale (I) fetuses heterozygous for the FecXI gene (I+), retarded germ cell development was observed at days 40 and 90 of gestation. In putative homozygous carriers (II) of the Inverdale gene, germ cell development appeared normal until day 100, but thereafter from day 120 normal secondary follicles were not observed, although many abnormal follicular-like structures were present. In both I+ and II fetuses no obvious differences in gonadotrophin concentrations have been noted. Collectively, the evidence suggests that the fecundity genes FecBB and FecXI, which affect ovulation rate in sexually mature females, are regulating organ differentiation or germ cell maturation or both processes during fetal life.

Animals↗
PubMed1994

Relationship between wing length and fecundity of a pestiferous midge, Glyptotendipes paripes (Diptera: Chironomidae).

The relationship between body size and fecundity of adult female Glyptotendipes paripes collected along southern shore areas of Lake Monroe, Sanford, FL, was studied by measuring wing length and examining ovaries, follicular development, and number of eggs/egg mass. Wing length of nulliparous, as well as parous females, had a significant (P < 0.01) linear relationship with dry body weight. Large females had a significantly (P < 0.01) higher number of follicles and eggs/egg mass than small females. No correlation existed between wing length and parity nor between wing length and age composition of field populations sampled between January and June 1993.

Animals↗