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Insulin sensitivity is normalized in the third generation (F3) offspring of developmentally programmed insulin resistant (F2) rats fed an energy-restricted diet
Daniel C Benyshek, Carol S Johnston, John F Martin, William D Ross
Nutrition & Metabolism , 2008, DOI: 10.1186/1743-7075-5-26
Abstract: Female Sprague Dawley rats (F0) were mated with control males and protein malnourished during pregnancy/lactation. F1 offspring were then weaned to adequate but energy-restricted diets into adulthood. F1 dams were fed energy-restricted diets throughout pregnancy/lactation. F2 offspring were also fed energy-restricted diets post weaning. F2 pregnant dams were maintained as described above. Their F3 offspring were split into two groups; one was maintained on the energy-restricted diet, the other was maintained on an adequate diet consumed ad libitum post weaning.F2 animals fed energy-restricted diets were insulin resistant (p < 0.05), while the insulin sensitivity of their F3 offspring equaled and surpassed that of controls on both the energy-restricted and adequate ad libitum postweaning diets (p < 0.05).Maternal energy-restriction did not consistently program reduced insulin sensitivity in offspring over three consecutive generations. The reasons for this remain unclear. It is possible that the intergenerational transmission of developmentally programmed insulin resistance is determined in part by the relative insulin sensitivity of the mother during pregnancy/lactation.An increasing number of experimental animal studies have demonstrated the intergenerational effects of developmental programming on a variety of phenotypic traits, including birth weight, blood pressure, and glucose metabolism. While the investigation of the multigenerational effects of developmentally programmed traits is widening, very few studies have explored the potential for these traits to be transmitted beyond the second (F2) generation, or with post weaning diets other than adequate-control [1]. A recent study reported that glucose metabolism is altered in the adequately-nourished offspring (F1 through F3 generation) of dams (F0) malnourished during gestation and lactation [2]. Here we extend those findings with a pilot study examining the intergenerational effects of energy-restricted diets
彭泽鲫F1和F2代雌、雄鱼激素含量及芳香化酶活力差异研究  [PDF]
郑尧,张永泉,陈家长,邴旭文,尹家胜,王在照
南京农业大学学报 , 2015, DOI: 10.7685/j.issn.1000-2030.2015.05.024
Abstract: [目的]本文旨在比较实验室和池塘养殖F1代,高、低密度实验室养殖F2代雌、雄鱼在激素含量和芳香化酶活力上的差异.[方法]采用ELISA方法对激素含量和芳香化酶活力进行了检测.[结果]发现实验室养殖F1代雌鱼全鱼组织雌二醇(E2)含量极显著高于雄鱼(P <0.01).池塘养殖F1代雌鱼脑中E2和睾酮(T)含量均极显著高于雄鱼,且卵巢中的芳香化酶活力极显著低于雄鱼(P <0.01).低密度养殖组F2代中卵巢T含量极显著低于高密度养殖组精巢中的含量(P <0.01).低密度养殖组F2代雌鱼脑、卵巢中的E2含量分别极显著高于高密度养殖组F2代雄鱼脑、精巢中的含量(P <0.01).F2代雌鱼脑中的芳香化酶活力极显著低于雄鱼中的,但卵巢中的芳香化酶活力极显著高于精巢中的(P <0.01).[结论]实验室和池塘养殖F1代,高、低密度实验室养殖F2代雌、雄鱼激素含量和芳香化酶活力存在差异.
[Objectives]The purpose of this study was to find the difference of steroid hormone levels and aromatase activities between different genders in laboratory and pond culture condition(F1 offspring),together with the same situation between high-density and low density laboratory culture groups(F2 offspring). [Methods]The present study used ELISA to detect steroid hormone levels and aromatase activities. [Results]The whole body 17β-estradiol(E2)levels in females were extremely significantly higher than the males of F1 offsprings under laboratory culture condition(P <0.01). Female brain E2 and testosterone(T)were extremely significantly higher than the males under pond culture condition(P <0.01). Aromatase activity in ovary was extremely significantly lower than testes(P <0.01). However in F2 offsprings,ovarian T in low-density group was extremely significantly lower than high-density group,while brain and ovarian E2 contents in low-density group were strongly significantly higher than high-density group respectively(P <0.01). Aromatase activities in female brains were highly significant lower than males,while aromatase activities in ovaries were strongly significantly higher than testes. [Conclusions]The present study presented the difference of steroid hormone levels and aromatase activities between different genders of F1,F2 offspring
Effects of prenatal stress on male offspring sexual maturity
Rodríguez,Nancy; Mayer,Nora; Gauna,Héctor F;
Biocell , 2007,
Abstract: prenatal stimulations have been shown to have long-term effects on at reproductive activity. we evaluated the influence of the prenatal stress on the hypothalamic-pituitary-gonad (hpg) axis in male off-springs from mothers with high number of offsprings per litter (hnl) and low number of offsprings per litter (lnl) after hypothesizing that the number of offsprings per litter may modify the effect of the prenatal stress on the hpg of adult offsprings. pregnant wistar rats were used for this study. immobilization (imo) stress was used, 30 min, 3 times per week, from the 5th to 21st day of pregnancy. the weight of adrenal and gonads, and the corticosterone (cor), testosterone (tes) and luteinizing hormone (lh) plasmatic levels were analyzed in the male offspring at 30, 45 and 70 days of age. the offspring males coming from lnl showed a decrease in testicle weight and tes levels, without changes in the plasmatic lh levels. however, the offspring of hnl showed a decrease of lh levels. it is possible to conclude that in lnl prenatal stress would produce alterations to gonadal level, while in hnl the effect of stress would be evident at pituitary level.
Effects of prenatal stress on male offspring sexual maturity
Nancy Rodríguez,Nora Mayer,Héctor F Gauna
Biocell , 2007,
Abstract: Prenatal stimulations have been shown to have long-term effects on at reproductive activity. We evaluated the influence of the prenatal stress on the hypothalamic-pituitary-gonad (HPG) axis in male off-springs from mothers with high number of offsprings per litter (HNL) and low number of offsprings per litter (LNL) after hypothesizing that the number of offsprings per litter may modify the effect of the prenatal stress on the HPG of adult offsprings. Pregnant Wistar rats were used for this study. Immobilization (IMO) stress was used, 30 min, 3 times per week, from the 5th to 21st day of pregnancy. The weight of adrenal and gonads, and the corticosterone (COR), testosterone (TES) and luteinizing hormone (LH) plasmatic levels were analyzed in the male offspring at 30, 45 and 70 days of age. The offspring males coming from LNL showed a decrease in testicle weight and TES levels, without changes in the plasmatic LH levels. However, the offspring of HNL showed a decrease of LH levels. It is possible to conclude that in LNL prenatal stress would produce alterations to gonadal level, while in HNL the effect of stress would be evident at pituitary level.
Seed Cotton Yield and Fibre Properties of F1 and F2 Hybrids of Upland Cotton  [PDF]
Mohammad Jurial Baloch,Abdul Rahim Lakho,Hidayatullah Butto,Rehmatullah Rind
Asian Journal of Plant Sciences , 2002,
Abstract: Relative yield and fibre properties of parents, F1 and F2 hybrids were compared. The variances among the genotypes were significant for yield, lint %, fibre length and fibre uniformity. Similarly, variances for all the four traits were significant among parents, F1 and F2 groups. In orthogonal contrast comparison, F2 hybrids expressed higher variance for yield and lint percent whereas for fibre length, F1s presented more variance and in fibre uniformity, parental lines have shown greater variance than the other two groups of genotypes. Orthogonal contrast comparisons were also made where parents versus F1 and F2 hybrids expressed more variance than F1 versus F2 hybrids for all the traits except fibre length. In relative performance, F1 and F2 hybrids, on an average produced 36.4 % and 20.1 % respectively, more yield than the parents. Though, F2 hybrids have shown 12.0% inbreeding depression, nevertheless six of the 12 F2 hybrids gave higher yield than F1 hybrids showing that potential in F2 hybrids exists to replace F1 hybrid crop development. Accordingly in Lint %, F1 and F2 hybrids were higher than parental lines but surprisingly F2 and not the F1s expressed 9.0 % and F1s only 3.0 % heterosis against parents, consequently F2s have shown 6.0% higher lint % than even F1 hybrids. In fibre length, F1s have demonstrated 3.0 % increase over parents whereas F2s were equal to parents. Both F1 and F2 gave 4.1% more uniform fibre over the parental lines.
Standard, inverse and triplet spin-valve effects in F1/S/F2 systems  [PDF]
S. V. Mironov,A. Buzdin
Physics , 2014, DOI: 10.1103/PhysRevB.89.144505
Abstract: We demonstrate that contrary to the common belief the critical temperature Tc of clean F1/S/F2 spin valves can depend non-monotonically on the angle between the magnetic moments of the ferromagnetic F1 and F2 layers. Depending on the system parameters the minimum of Tc may correspond to parallel, antiparallel or non-collinear mutual orientation of magnetic moments. Such anomalous behavior can reveal itself only provided the ferromagnetic layers differ from each other and it completely disappears in the dirty limit.
Association analysis in F1 and F2 generations of rice under reproductive stage drought stress
P .Yogameenakshi and P. Vivekanandan
Electronic Journal of Plant Breeding , 2010,
Abstract: Drought stress occurring at reproductive stages has severe impact in rice yield as it adversely affects grain filling. Ricegenotypes with earliness (to avoid terminal drought), better internal water balance and deeper root system (to extract waterfrom deeper layers of soil) tend to withstand to a greater extent and give nominal yields under drought situations. In order tounderstand the nature and extent of association between traits of drought tolerance and grain yield under reproductive stagedrought stress, association analysis was performed in F1 and F2 generations of rice. In F1, days to 70% RWC and root traitsviz., root thickness, root/shoot ratio, root length, root volume and dry root weight exhibited significant positive associationwith grain yield/plant while in F2, spikelet fertility and root traits viz., root length, dry root weight, root thickness androot/shoot ratio had positive and significant association with grain yield. Negative and significant association was noticedbetween grain yield and days to 50% flowering, leaf drying and drought recovery scores in F1 and between grain yield anddays to flowering in F2. Positive intercorrelation was noticed between spikelet fertility and root traits in both F1 and F2.Hence selection based on earliness and root characters will be helpful in identifying genotypes with better drought tolerancecapacity and grain yield under rainfed conditions. Productive tillers/plant, 100 grain weight and harvest index in F1 andharvest index, root length and dry root weight in F2 were the major contributors of grain yield by way of their positive andhigh direct effects.
Heritability of Quantitative Traits in F1 and F2 Progenies of some Domestic and Foreign Tobacco Varieties  [PDF]
Ana Korubin — Aleksoska,Jane Aleksoski
Agriculturae Conspectus Scientificus (ACS) , 2013,
Abstract: Aim of this paper was to investigate heredity of plant height, number of leaves per plant, middle zone leaf area, green mass yield and dry matter yield per plant in F1 and F2 progeny of four tobacco varieties: Prilep – P12-2/1, Pobeda – P-2, Jaka –YV125/3 and Forchheimer Ogrodowny – FO. In F1 progeny the highest narrow-sense heritability value was estimated for dry matter yield per plant while in F2 progeny was for middle zone leaf area. In both investigated generations the highest broad-sense heritability value was estimated for green mass yield per plant, while the lowest narrow and broad-sense heritability was estimated for number of leaves per plant.
Phenotypic variation of F1 and F2 populations from three species of Solanum L. (Solanaceae)
OA Oyelana, RE Ugborogho
African Journal of Biotechnology , 2008,
Abstract: Emerging chromosome types in some Solanum species underscore inherent potentials and possible>new and expanded genome. Interspecific crosses involving the varieties of Solanum melongena L.,Solanum macrocarpon L. and Solanum aethiopicum L. were carried out to assess species phylogenetic relationships and the extent of evolutionary changes with a view to improving the agronomic characters in the hybrids. The dimensions of leaves, petals and fruits in the F1 hybrids were intermediate in values between parents while parental influence was significant in such characters as growth habit, inflorescence types and colour of flowers. Pollen viability was depressed from 97.3 – 71% in parents to 56.8 - 48.8% in the F1 and consistently lowered from 48.6 – 38.2% in the F2 hybrids but restored (63.8%) in an F2 plant. Fruits were few on inflorescence, small sized with generally fewer seeds in the F1 (67 - 132) and F2 (52 – 135) hybrids compared with the parents (87 – 384). A single flowered inflorescence from a cross (S. melongena ‘Melongena’ x S. aethiopicum) revealed a novel gene and possible selective ecological advantage over other hybrids. The incomplete restoration of some of the masked characters in the F2 hybrids suggests a near-complete homogenization of parental genomes and/or chromosomal disharmony through silent genomic changes. These might have prevented sufficient chromosomal rearrangement and full homology for improved vigour in many of the F2 hybrids.
Maturity of F1 grape hybrids originated in Pink Traminer  [cached]
Radu SESTRAS,Marin ARDELEAN,Sergiu Dan MOLDOVAN,Elena TAMAS
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 1998,
Abstract: In eight hybrid combinations in which one of the parents (either maternal of paternal) was cv. Pink Traminer (Gewurztraminer), 2.284 F1 individuals have been analyzed concerning the maturity of grapes. Obvious differences were noted among different combinations and within the same combination, depending on whether Pink Traminer had been used as a maternal or paternal genitor. These data suggest a possible maternal effect on the analyzed characteristic. Grape maturity seemed to be polygenicall inherited, heritability (in broad sense) showing high values while the one in narrow sense small and very small values, suggesting that additivity is not playing the most important role in the inheritance of this character in grapes.
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