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PubMed1975

[The morphofunctional condition of the basic organ systems, life span and fecundity of the domestic cricket, Acheta domestica, during normal imaginal development and following allatectomy].

3 main periods of imaginal development: juvenility, reproduction, ageing, were established in Acheta domestica and characterized by morphological and functional features of some organs (integument, wings, fat body, wing muscles, ovaries, and body proportions). Allatectomized crickets remain in the first period up till the day of death; this allowed to suggest that the hormone of corpora allata in imago controls the normal correlated development of different organs and tissues and ensures the transition to subsequent periods of imaginal ontogenesis. In allatectomized crickets of both the sexes, the duration of imaginal life is markedly longer and the fecundity of females is much lower. It is suggested that the hormone of corpora allata controls the life span and the fecundity independently.

Animals↗
PubMedDate not supplied

[Body size and fecundity of Juxtafabia muliniarum (Brachyura: Pinnotheridae) associated with Saccostrea palmula (Bivalvia: Ostreidae), Costa Rica].

Size and fecundity observations of pea crab (Juxtafabia muliniarum) from the paleal cavity of the oyster Saccostrea palmula were made from May 1998 to May 1999. Infestation frequency was 18.52% in a sample of 540 oysters. Of 136 pea crabs, 36% were couples, 60% were single females and 4% were single males. The mean caparace length of J. muliniarum was 5.6 +/- 0.74 mm (range 4.0 to 7.6 mm) for females and 2.71 +/- 0.60 mm (range 1.6 to 4.0 mm) for males. The mean weight was 0.180 +/- 0.084 g (range 0.06 to 0.4 g) for females and 0.011 +/- 0.003 g (range 0.01 to 0.02 g) for males. Ovigerous females (43.75% of all females) were found in all months. The caparace length-fecundity relationship was F = 3904.6 Ln (Lc)--4651.1. The caparace length-weight relationship was P = 6 x 10(-4) Lc3.2122. The mean sex-ratio was 1.0 male: 2.4 females. Saccostrea palmula infected only by females was the dominant group (60.78%). This mollusk is a new host record for the crab.

Animals↗
PubMed1975

[Fecundity and embryonal mortality of four inbred lines of mice, BALB/c, B10.CW, A/Sn CC57W and their hybrids].

The object of this investigation was the potential fecundity of four inbred strains of mice, viz. BALB/c, B10.SW, CC57W, A/Sn and of their different hybrid combinations. The inbred strains studied had different normal ovulation numbers varying from 9,2 to 11,9 and different death-rate of embryos before (10,99-39,49%) and after (9,05-22,47%) the implantation. The numbers of live embryos per female in the strains A/Sn, b10.cw and CC57W were practically equal to one another, but significantly larger than in the strain BALB/c. Interlinear crosses resulted in a considerable decrease of the totalembryonic deathrate, while the normal ovulation number did not undergo any changes. The number of liver embryos in simple hybrids did not differ significantly from that in the maternal inbred strains. Therefore the heterozygosity of embryos did not affect significantly the potential fecunidity of females. The number of surviving embryos per female increased in the cross between the simple hybrids (BALB/cXB10.CW) X (CC57WXA/Sn) to 8,9+/-0,37. This heterosis was the result of the total death-rate of embryos down to 14,89%. Asit is shown by the comparison of the potential fecundity of pregnant females carrrying homo- and heterozygous embryos to that of pregnant hybrid females, the rate of survival of embryos depends more on th

Animals↗
PubMed1999

[In vivo anti-fecundity effect of recombinant Sjc26 GST against Schistosoma japonicum in immunized mice].

AIM: To observe the anti-fecundity effect of recombinant Sjc26 GST against Schistosoma japonicum and its mechanism. METHODS: Male ICR mice were immunized with rSjc26 GST. Five days after final injection, mice of the immunization and control groups were challenged with 40 +/- 1 S. japonicum cercariae. All mice were sacrified at 6 weeks after challenge. RESULTS: The worm reduction rate was 30.0%, and the egg reduction rates in the liver and in the spleen were 57.1% and 79.9%, respectively. Inhibition of the vitelline gland and testis was also observed by transmission electron microscopy. The number of vitelline globes, vitelline droplets and lipid droplets in the cytoplasm of vitelline cell and the number of lipid droplets in the supporting cells and the number of spermatids in the testis were apparently reduced. CONCLUSION: The damage of the main reproductive organs of Schistosoma japonicum was one of the factors responsible for rSjc26 GST-bound anti-fecundity action.

Animals↗
PubMed1963

SOME FACTORS AFFECTING THE FECUNDITY OF BIOMPHALARIA PFEIFFERI (KRAUSS) IN GLASS AQUARIA.

Little being known of the effect of artificial conditions on Biomphalaria snails maintained in laboratory aquaria, experiments were conducted to determine some of the basic requirements of these snails, expressed in terms of the influence of various factors on their growth, fecundity and mortality. Among the factors studied were diet, artificial aeration, the chemical and physical properties of the water, and the presence of human urine in the water.The results obtained suggest that a diet of dehydrated lettuce and lucerne, no artificial aeration, a CaCO(3) concentration of approximately 18 p.p.m., a sodium/calcium ratio of 1, and mild "pollution" give optimum fecundity and growth and low mortality with Biomphalaria pfeifferi (Krauss).

Africa↗
PubMed2003

[Sublethal effects of insecticides on fecundity of multicolored Asian ladybird Harmonia axyridis].

The effects of sublethal doses of 6 insecticides (imidacloprid, rotenone, fenvalerate, abamectin, pirimicarb and azadirachtin) on the fecundity of multicolored Asian ladybird Harmonia axyridis were determined respectively. The results showed that in all treatments, the daily average number of eggs per female ladybird was about 40-55. Ladybirds pretreated with imidacloprid by contact and feeding methods, and with rotenone by feeding method produced significantly fewer eggs, compared with control. But the accumulative oviposition of ladybirds pretreated with 6 insecticides at sublethal level was no significant differences, compared with untreated ladybirds. The hatching rates of the eggs laid by ladybirds pretreated with 6 insecticides by two methods were all lower than that of control. The accumulative survivals from egg to pupal stage of all treatments decreased significantly. The developmental duration from egg to pupa of those treated with imidacloprid by two methods and with fenvalerate by contact method prolonged significantly, while that of those treated with rotenone by two methods and with fenvalerate, abamectin, pirimicarb, and azadirachtin by feeding method shortened obviously, but that of those treated with rotenone and abamectin by contact method had no differences with control. After the eggs were immersed with sublethal concentrations of imidacloprid, rotenone, fenvalerate and abamectin, the successful hatching rates were all lower than that of control, and the development periods prolonged clearly. The 1st instar larval survival rates of those treated with fenvalerate decreased significantly, and the survivals from 2nd instar larval to pupal stage also reduced to some extent. The total developmental duration of those treated with rotenone and fenvalerate prolonged significantly. These findings suggested that the effects of insecticides at low doses on the fecundity of ladybird were very complicated. The class, action mode, toxicity and exposure route of insecticides could affect the results of experiments.

Animals↗
PubMed2005

Toxicity and effects of microbial mosquito larvicides and larvicidal oil on the development and fecundity of the tadpole shrimp Triops newberryi (Packard) (Notostraca: Triopsidae).

Tadpole shrimp (TPS), Triops newberryi (Packard) (Notostraca: Triopsidae), is a predatory agent for immature mosquitoes breeding in aquatic habitats. This biological control agent could be used with other larvicides in mosquito control programs. In order to elucidate compatibility of the TPS and commonly used mosquito larvicides, studies were initiated to investigate effects of Bacillus thuringiensis ssp. israelensis (B.t.i.) de Barjac, Bacillus sphaericus Neide and Golden Bear-1111 larvicidal oil on growth, longevity, and fecundity of TPS in laboratory and field. The exposure of TPS to high dosages of B.t.i. and B. sphaericus in the laboratory or in the field did not have significant adverse effects on growth, longevity, and fecundity. These results indicate that TPS are compatible with microbial larvicides and can be used jointly in practical mosquito control programs. The larvicidal oil GB-1111, on the other hand, caused almost 100% mortality within 48 h after treatment in the laboratory even at the low dosage of 0.38 gallons/ac. The impact of oil in the field was less severe, as significant adverse impact on population density was noted at 1 gallon/ac when water temperatures were warmer, or 2 gallons/ac when water temperatures were cooler. Almost 100% mortality within 48 h was noted at 2 gallons/ac when water temperatures were warmer or at 4 gallons/ac when the water temperatures were cooler. These results indicate incompatibility between this larvicidal oil and TPS at the higher rates of the label range, and joint use of TPS and larvicidal oil at dosages of 1-2 gallons/ac or greater, depending on water temperatures, should be avoided.

Animals↗
PubMedDate not supplied

[Some patterns of age and geographical variation in fish fecundity].

Some patterns of age and geographical variation in fecundity indices were analyzed in three freshwater fishes (river perch, bream, and Sevan khramulya). A trend to increase in the ovarian relative weight and mature egg size with age has been revealed. Two species with a wide range (perch and bream) demonstrated a tendency to decrease in the ovarian relative weight and increase in the definitive oocyte weight in females of populations living in the geographical center of the range. The coefficient of correlation between the absolute individual fecundity and body weight of females was proposed as a population marker of the fish reproductive system.

Age Factors↗
PubMed2006

[Effects of spring wheat varieties on growth, development and fecundity of Sitobion avenae (F.) (Homoptera: Aphididae)].

Effects of seven varieties of spring wheat on the population parameters of Sitobion avenae (F.) were investigated at 25 degrees C in the laboratory. The results indicated that there were significant differences in the developmental duration, mortality of nymph aphids, the longevity and fecundity of adults. The adults had shorter longevity and poorer fecundity when reared with the leaves of higher resistant w heat varieties. The level of wheat resistance was in order of Liaochun 10 >02C-MB >Xinchun 6 >Bafeng 1> Yongliang 4> Neimai 19> Menghua 1 using the intrinsic rate of increase (r(m)) as an index of wheat antibiosis to aphids, which was correspondent well with that in fields.

Animals↗
PubMed2006

Malathion-induced oxidative stress in a parasitoid wasp: effect on adult emergence, longevity, fecundity, and oxidative and antioxidative response of Pimpla turionellae (Hymenoptera: Ichneumonidae).

Effects of an organophosphorus insecticide, malathion, on survivorship and lipid peroxidation of the greater wax moth, Galleria mellonella (L.), pupae were investigated by rearing the newly hatched larvae on an artificial diet containing 0.01, 0.1, 1, 10, and 100 ppm of the insecticide. As bioindicators of long-term physiological stress responses, the adult emergence rate, longevity, and fecundity associated with lipid peroxidation level and antioxidant enzyme activity in the endoparasitoid Pimpla turionellae (L.) (Hymenoptera: Ichneumonidae) were determined by rearing the parasitoid on a factitious host, G. mellonella pupae treated with malathion. At 100 ppm, malathion significantly decreased pupation rate of G. mellonella larvae and the rate of adult emergence of the parasitoid from these pupae. This concentration resulted in a significant increase in the lipid peroxidation product malondialdehyde (MDA) in both the host and the parasitoid. Malathion at 1 and 10 ppm significantly increased pupation rate and lipid peroxidation level of G. mellonella pupae. The adult emergence rate of P. turionellae was significantly decreased from 63.7 to 20% by these concentrations, whereas MDA content was increased by two- and three-fold, respectively, compared with the control (45.3 +/- 3.2 nmol/ g protein). The longevity of adults was significantly extended from 52.5 +/- 5.7 to 75.7 +/- 6.3 d when the parasitoids emerged from host pupae exposed with 0.1 ppm malathion. At low concentrations (0.01 and 0.1 ppm), malathion significantly increased the number of eggs laid per female per day. However, the lowest concentration (0.01 ppm) had no significant effect on hatchability, whereas 0.1 ppm of the insecticide resulted in significant decrease in egg hatch compared with the control. A significant increase in total superoxide dismutase (SOD) activity for low concentrations of malathion (0.01-1 ppm) was found compared with the control. There was a significant positive correlation of SOD activities with adult longevity and fecundity. This study suggested that malathion-induced oxidative stress was causative factor in the deterioration of biological fitness and that increased SOD activities may have resulted in decreased oxidative damage, which retarded the rate of deteriorative physiological changes in P. turionellae in response to sublethal doses of malathion.

Animals↗
PubMed2006

Age, reproduction and fecundity of the spined loach Cobitis taenia L. (Pisces, Cobitidae) from Lake Klawój (Poland).

This is the first study concerning the features of the reproduction process of the karyologically identified spined loach C. taenia (2n=48). The histology of 71 ovaries, and gonadosomatic index (GSI) of karyologically identified spined loach Cobitis taenia L. from Lake Klawój (Northern Poland) were examined. The absolute and relative fecundity of 25 females was estimated by gravimetric method. The age of fish was determined according to the annual increments of otholits. The spawning of C. taenia from Lake Klawój took place from May to July, at a water temperature exceeding 18.5 degrees C. The GSI values at the beginning of the reproduction period ranged from 7 to 19%. The average absolute fecundity of females was 2078 eggs, with the number ranging from 869 to 3371 eggs. High individual variability in the gonad histology and the GSI values during the reproductive period was observed. Such variability could be the result of beginning the reproduction process in the fish at various times and, probably, due to the various numbers of batches laid and various numbers of eggs per batch.

Age Factors↗
PubMed1991

Correlation and regression studies between pupal weight and fecundity of muga silkworm Antheraea assama Westwood (Lepidoptera: Saturniidae) on four different foodplants.

Female pupal weight and fecundity of mother moth of Antheraea assama Westwood fed with four different food plants have been studied. Litsaea polyantha fed females showed significantly higher pupal weight and higher rate of oviposition in comparison to three food plants Machilus bombycina, Litsaea salicifolia and Cinnamomum glaucescens. The number of eggs laid was correlated with the pupal weight. The correlation co-efficient (r = 0.9730) showed positive and significant correlation at 1% level. The pupal weight was found to be the best and genuine estimator of fecundity.

Animals↗
PubMed1989

Fecundity of two hillstream fishes, Garra lamta (Ham.) and Garra gotyla gotyla (gray).

The fecundity of two hillstream fishes, Garra lamta and G. gotyla gotyla, is related to their total body length (L), total body weight (W), ovary length (X) and ovary weight (V). The relationships to L, W, X and V were all linear. The correlation coefficient values (r) showed that total body length and total body weight were the best indices in fecundity estimates in both fishes.

Animals↗
PubMed1988

[Use of the concept of fecundity in the prognosis of infertility].

In taking note of the fecundability it becomes possible to calculate the distribution curve for delays in becoming pregnant for couples who want to have a pregnancy. In the first part of the paper tables are presented to correspond to different fecundabilities and contain the delays in conception and other indices that can measure the fertility of such couples. Il the second half the results are applied to concrete situations that go with different causes of infertility, so that couples affected with certain conditions can know their own prognosis as a function of the delay already suffered since starting to try for a pregnancy.

Adult↗
PubMed1988

Laboratory oviposition, fecundity and egg hatching ability of colonized Anopheles albimanus from southwestern Mexico.

Fecundity, oviposition patterns and egg hatching characteristics were studied in two colonies of Anopheles albimanus isolated from the Pacific coast of southern Mexico. Fecundity was inversely proportional to the cage space available to the female and was influenced by the bloodmeal source, feeding method and previous feeding history. The length of the gonotrophic cycle decreased with succeeding experience from a mean 6.6 in the first to 2.6 days for the fifth cycle. Oviposition timing was also dependent on availability of oviposition substrate. Hatching success of eggs increased significantly when the oviposition site was witheld until 48 hr post-bloodmeal.

Animals↗
PubMed1986

Impact of abortion on subsequent fecundity.

The impact of abortion on subsequent fecundity has been extensively studied, especially since abortion was legalized in Eastern Europe during the 1950s and 1960s and in Western Europe and the USA during the 1960s and 1970s. A review of this literature reveals a number of consistent findings. First, women who choose to have their first pregnancy terminated are at no increased risk of failing to conceive at a later date. Exceptions include abortions complicated by infection leading to pelvic inflammatory disease (PID). However, this combination of factors occurs very infrequently. Second, women whose first pregnancy is terminated by vacuum aspiration are at no increased risk of subsequent ectopic pregnancy. Exceptions may be women whose abortion is complicated by pre-existing C. trachomatis and others who experience post-abortion infection leading to PID. Third, women whose first pregnancy is terminated by vacuum aspiration are at no increased risk of subsequent mid-trimester spontaneous abortion, preterm delivery or low birthweight, when compared with women who are pregnant for the first time. Fourth, women whose first pregnancy is terminated by D&C may have an increased risk of subsequent ectopic pregnancy, mid-trimester spontaneous abortion and low birthweight. Fifth, more research is needed before it is clear whether multiple induced abortions carry an increased risk of adverse pregnancy outcomes. Finally, too little is known about fecundity following mid-trimester abortion procedures to state definitively that they carry no increased risk of adverse outcomes. However, studies to date suggest that instillation procedures carry little, if any, excess risk. Risks related to dilation and evacuation, if any, may be related to the method and extent of cervical dilation.

Abortion, Induced↗
PubMed1986

Artificial feeding of West African Simulium damnosum Theobald s.l. (Diptera: Simuliidae) through membranes and their subsequent fecundity.

Simulium damnosum s.l. females were offered blood through artificial membranes using a feeding apparatus in which the blood is kept warm and stirred. Feeding rates and egg production were compared using a synthetic silicone or a latex membrane and ten different kinds of blood with and without added adenosine-tri-phosphate (ATP). Feeding rates were usually higher with silicone than with latex membranes. Wild flies captured just before starting to feed on man, usually fed better than females that had emerged from pupae in the laboratory. Wild-caught flies showed best results when deep-frozen human blood with EDTA or fresh human blood from a blood bank was offered through a silicone membrane. Using a latex membrane they fed best on "instant" and fresh human blood from a blood bank. Laboratory-emerged females which were offered blood only through the silicone membrane, fed best on freeze-dried porcine blood or on human blood with EDTA, both with ATP. Optimal feeding rates were obtained with one day old flies and membrane temperatures between 37.0 and 39.5 degrees C. Real fecundity depended on blood-meal volume. Females that took a complete meal on man produced 377 eggs per fly. Since a higher percentage of flies fed through membranes took small or medium sized blood meals, their fecundity was correspondingly lower (295 eggs per fly).

Animals↗
PubMed1986

Concentration of ivermectin in bovine serum and its effect on the fecundity of psoroptic mange mites.

The concentration-time profile of ivermectin in serum was determined for 3 Hereford heifers. The mean maximum serum concentration, 29 ng of ivermectin/ml, was obtained 48 hours after single subcutaneous injection of 200 micrograms/kg of body weight. The fecundity of mites placed on 9 treated animals at 5, 9, 12, 15, 18, and 21 days after injection was reduced by 96% to 99%. At 24 days after treatment, when serum concentration had decreased to about 2 ng/ml, the capability of mites to produce eggs increased to 50% of mites from nontreated calves. At 27 and 30 days after the drug was injected, egg production by mites on treated calves was equivalent to that of mites on nontreated calves. The reduced fecundity resulted from an almost complete cessation of oviposition by females after only a 1-day exposure to ivermectin-treated calves.

Animals↗