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Embryo Survival (embryo + survival)
Selected AbstractsGrowth, Maturation, Induced Spawning, and Production of the First Generation of South American Catfish, Pseudoplatystoma sp., in North AmericaJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2008Konrad Dabrowski Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11-ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11-h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 109 and 15.5 × 109 spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii. [source] Developmental toxicity in zebrafish (Danio rerio) embryos after exposure to manufactured nanomaterials: Buckminsterfullerene aggregates (nC60) and fullerolENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2007Xiaoshan Zhu Abstract The present paper summarizes, to our knowledge, the first study regarding the developmental toxicity of stable buck-minsterfullerene aggregates suspended in water (nC60) using zebrafish (Danio rerio) as a vertebrate model. Zebrafish embryo survival, hatching rate, heartbeat, and pericardial edema were noted and described within 96 h of exposure. Fullerol (a hydroxylated C60 derivative, C60(OH)16,18) at 50 mg/L did not exert toxicity to zebrafish embryos. In contrast, nC60 at 1.5 mg/L delayed zebrafish embryo and larval development, decreased survival and hatching rates, and caused pericardial edema. Toxicity was mitigated by adding an antioxidant (glutathione), which suggests that a free radical,induced mechanism or another form of oxidative stress played a role in developmental toxicity. [source] MHC-linked susceptibility to a bacterial infection, but no MHC-linked cryptic female choice in whitefishJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 1 2004C. Wedekind Abstract Non-random gamete fusion is one of several potential cryptic female choice mechanisms that have been postulated and that may enhance the survival probability of the offspring. Previous studies have found that gamete fusion in mice is influenced by genes of the major histocompatibility complex (MHC) region. Here we test (i) whether there is MHC-dependent gamete fusion in whitefish (Coregonus sp.) and (ii) whether there is a link between the MHC and embryo susceptibility to an infection by the bacterium Pseudomonas fluorescens. We experimentally bred whitefish and reared sibships in several batches that either experienced or did not experience strong selection by P. fluorescens. We then determined the MHC class II B1 genotype of 1016 surviving larvae of several full sibships. We found no evidence for MHC-linked gamete fusion. However, in one of seven sibships we found a strong connection between the MHC class II genotype and embryo susceptibility to P. fluorescens. This connection was still significant after correcting for multiple testing. Hence, the MHC class II genotype can considerably influence embryo survival in whitefish, but gamete fusion seems to be random with respect to the MHC. [source] A saltwater flotation technique to identify unincubated eggsJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2009Carol A. Devney ABSTRACT Field studies on nesting birds sometimes involve questions related to nest initiation dates, length of the incubation period, or changes in parental incubation behavior during various stages of incubation. Some of this information can be best assessed when a nest is discovered before the eggs have undergone any incubation, and this has traditionally been assessed by floating eggs in freshwater. However, because the freshwater method is not particularly accurate in identifying unincubated eggs, we developed a more reliable saltwater flotation method. The saltwater method involves diluting a saturated saltwater solution with freshwater until a salt concentration is reached where unincubated eggs sink to the bottom and incubated eggs float to the surface. For Laughing Gulls (Leucophaeus atricilla), floating eggs in freshwater failed to identify 39.0% (N= 251) of eggs that were subsequently found by candling to have undergone incubation prior to collection. By contrast, in a separate collection of gull eggs, no eggs that passed the saltwater test (N= 225) were found by a later candling to have been incubated prior to collection. For Double-crested Cormorants (Phalacrocorax auritus), floating eggs in freshwater failed to identify 15.6% (N= 250) of eggs that had undergone incubation prior to collection, whereas in a separate collection, none of the eggs that passed the saltwater test (N= 85) were found by a later candling to have been incubated prior to collection. Immersion of eggs in saltwater did not affect embryo survival. Although use of the saltwater method is likely limited to colonial species and requires calibrating a saltwater solution, it is a faster and more accurate method of identifying unincubated eggs than the traditional method of floating eggs in freshwater. RESUMEN Los estudios de campo sobre la nidificación a veces involucran preguntas relacionadas a las fechas de iniciación de la nidificación, la duración del periodo de incubación o cambios en el comportamiento de incubación de los padres durante varias etapas del periodo de incubación. Parte de esta información se puede evaluar mejor cuando un nido es descubierto antes de que los huevos han sido incubados y esto se ha tradicionalmente evaluado mediante la flotación de los huevos en agua dulce. Sin embargo, por la razón que este método no es particularmente preciso en la identificación de huevos que no han sido incubados, hemos desarrollado un método de flotación en agua salada más fiable. El método de agua salada involucra la dilución de una solución saturada de agua salada con agua dulce hasta llegar a una concentración en la cual los huevos no-incubados se hunden hasta el fondo y los huevos incubados flotan. Para huevos de Leucophaeus atricilla, la flotación de huevos en agua dulce no pudo identificar el 39.0% (N= 251) de los huevos que fueron subsecuentemente identificados mediante el uso de luz de vela de haber sido incubados antes que fueron colectados. En contraste, un una colección separada de huevos de esta especie, ninguno de los huevos que pasaron la prueba de agua salada (N= 225) fueron identificados subsecuentemente mediante el método de luz de vela como incubados. Para los huevos de Phalacrocorax auritus, la flotación de huevos en agua dulce no pudo identificar el 15.6% (N= 250) de los huevos que fueron incubados antes de ser colectados, mientras que en una colección separada, ninguno de los huevos que pasaron la prueba de agua salada (N= 85) fueron identificados en una prueba posterior usando luz de vela como incubados antes de ser colectados. La inmersión de huevos en agua salada no afectó la supervivencia del embrión. Aunque el uso del método de agua salada es probablemente limitado a especies que nidifican en colonias y requiere de calibrar una solución de agua salada, es un método más rápido y fiable para identificar los huevos no-incubados en comparación al método tradicional de flotar los huevos en agua dulce. [source] The effect of different kinds of electrolyte and non-electrolyte solutions on the survival rate and morphology of zebrafish Danio rerio embryosJOURNAL OF FISH BIOLOGY, Issue 7 2009F. Lahnsteiner The effect of electrolyte and non-electrolyte solutions on the survival and on the morphology of zebrafish Danio rerio embryos was investigated. Embryos in different ontogenetic stages were incubated in electrolyte (NaCl, KCl, MgCl2 and CaCl2) and non-electrolyte solutions [sucrose and polyvinylalcohol (PVA)] of different concentrations for 5 , 15 min. The embryos were hatched to the long-pec stage and the effective concentrations which caused a 50% decrease in embryo development (EC50) were determined. The morphometric changes, which were caused by the test solutions, were measured. Ion channel blockers were used to see if active ion transport played a role for embryo survival. Finally, dechorionated embryos were exposed to the test solutions to get indications about the importance of chorion and perivitelline space. For 12 hours post fertilization (hpf) embryos and a 15 min exposure period, EC50 was highest for MgCl2 (1·60 mol l,1), followed by sucrose (0·73 mol l,1), NaCl (0·49 mol l,1), KCl (0·44 mol l,1), CaCl2 (0·43 mol l,1) and PVA [0·0005 mol l,1 (2·2%)]. EC50 were lower for early embryonic stages than for advanced stages for all solutions with exception of MgCl2 and sucrose. At the EC50, MgCl2 and CaCl2 solutions did not induce morphometric changes. NaCl and sucrose solutions induced reversible morphometric changes, which were compensated within 10 min. Only the EC50 of KCl and PVA solutions induced permanent morphometric changes, which could not be compensated. Incubation of embryos in electrolyte and non-electrolyte solutions together with ouabain (blocker of Na+, K+ ATPase), HgCl3 (dose-dependent inhibition of aquaporine channels), verapamil (inhibition of calcium and magnesium uptake) and amiloride (inhibition of sodium uptake) significantly decreased the per cent of embryos developing to the long-pec stage in comparison to the same solutions without blockers. Ouabain and HgCl3 also induced morphometric changes. For dechorionated embryos the survival rates in water and in the different test solutions were similar to untreated embryos. [source] Broods of attractive three-spined stickleback males require greater paternal careJOURNAL OF FISH BIOLOGY, Issue 4 2006T. C. M. Bakker The relationship between egg number and survival in nests of three-spined sticklebacks Gasterosteus aculeatus was tested in the field. Nests were deprived of paternal care during a variable period by removal of the father while preventing egg predation by protection of the nest by a net. Upon male removal, a number of male traits were quantified. Nest-content variables and embryo survival were assessed at the end of the deprivation period. Proportional egg mortality was significantly positively correlated with the length of the deprivation period, the number of eggs present in the nest and egg size, thus suggesting that nests with more and larger eggs need more paternal care. Males with the most symmetrical ventral spines achieved the highest reproductive success as measured by the number of eggs in the nest. In addition, their nests contained relatively larger eggs. Spine length symmetry correlated with the blue intensity of the eye thus giving females several cues to assess male quality. [source] TIMP-1 as candidate gene for embryo survival in two divergent lines selected for uterine capacity in rabbits,MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 6 2006Jordi Estellé Abstract Selection on uterine capacity has been used in animal breeding as a way to improve the litter size. A divergent selection experiment for uterine capacity was performed in rabbits during ten generations. After the first generations of selection, large differences in number of implanted embryos were obtained between high and low lines. The major part of the differences between lines was due to embryo survival. A segregation analysis suggested the presence of a major gene affecting the reproductive traits. The objective of this work was to test the TIMP-1 gene as a candidate gene for embryo survival in rabbits since it stands up as a target for the investigation of reproductive problems in humans. We have analyzed the parental generation of a F2 cross which consists of 8 and 14 animals from the high and low uterine capacity lines, respectively. The rabbit TIMP-1 gene structure and sequence has been determined, including the proximal promoter region. Despite of the absence of polymorphism between lines in the screened regions (CDS, proximal promoter, exon 1, intron 1, and exon 2), a real-time RT-PCR quantification of the TIMP-1 mRNA in oviduct has shown significant differences between high and low lines at 62 hr of gestation, just when rabbit embryos are located in the oviduct, postulating TIMP-1 as an interesting candidate gene to be involved in the phenotypic differences between the two rabbit lines. Mol. Reprod. Dev. © 2006 Wiley-Liss, Inc. [source] Actions of Tumor Necrosis Factor-, on Oocyte Maturation and Embryonic Development in Cattle,AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2003P. Soto Problem:, Infertility can accompany mastitis in cattle. Involvement of tumor necrosis factor- , (TNF- ,) in this phenomenon is suggested by observations that circulating concentrations of TNF- , are elevated after intramammary infection or infusion of endotoxin. It was hypothesized that (1) TNF- , acts on the oocyte during maturation to decrease the percent of oocytes that cleave and develop following fertilization; (2) exposure of embryos to TNF- , after fertilization reduces development to the blastocyst stage; and (3) TNF- , increases the proportion of blastomeres that undergo apoptosis in a stage-of-development dependent manner. Method of study:, In one experiment, oocytes were matured with various concentrations of TNF- , and then fertilized and cultured without TNF- ,. In another study, embryos were cultured with TNF- , for 8 days beginning after fertilization. Finally, embryos were collected at the two or four-cell stage (at 28,30 hr after insemination) or when ,9-cells (at day 4 after insemination) and cultured ± TNF- , for 24 hr. The proportion of blastomeres undergoing apoptosis was then determined by the TUNEL procedure. Results:, Addition of TNF- , to maturation medium did not affect the proportion of oocytes that cleaved. However, the percent of oocytes that developed to the blastocyst stage at day 8 after insemination was reduced (P = 0.05) at all TNF- , concentrations tested (0.1,100 ng/mL). When added during embryo culture, there was no significant effect of TNF- , on the proportion of oocytes that became blastocysts. In addition, TNF- , did not induce apoptosis in two and four-cell embryos. For embryos ,9-cells, however, 10 and 100 ng/mL TNF- , increased (P < 0.05) the percent of blastomeres labeling as TUNEL-positive. Conclusion:, TNF- , can have deleterious actions on oocyte maturation that compromise development of the resultant embryo. While exposure of fertilized embryos to TNF- , did not inhibit development to the blastocyst stage, TNF- , increased the percentage of blastomeres undergoing apoptosis when exposure occurred for embryos ,9-cells. Increased blastomere apoptosis could conceivably compromise subsequent embryo survival. [source] Analysis of the oviductal glycoprotein 1 polymorphisms and their effects on components of litter size in rabbitsANIMAL GENETICS, Issue 5 2009M. Merchán Summary The objective of this work was to study the effect of the oviductal glycoprotein 1 (OVGP1) genotype and mRNA expression on litter size and other fertility measures, as OVGP1 has positive effects on fertilization and early embryo development. We have analysed an F2 cross of two lines of rabbits divergently selected for uterine capacity. The OVGP1 mRNA expression was analysed in both lines, but no differences were observed between them. The promoter region and mRNA were sequenced in the F0 generation, and 17 polymorphic sites were found to co-segregate in three haplotypes (A, B and C). An association study was performed between several reproductive traits and a triallelic microsatellite identified in the promoter region as well as a non-synonymous SNP located in exon 11 [g.12944C>G (p.Arg468Gly)]. The alleles g.12944G and g.325(GT)14T(G)5 of the B haplotype have a positive effect on the total number of kits born, number born alive, number of implanted embryos and foetal and prenatal embryo survival. [source] Molecular characteristics of the porcine DLK1 and MEG3 genesANIMAL GENETICS, Issue 2 2008X. P. Li Summary Imprinted genes play important roles in embryo survival and postnatal growth regulation. The DLK1 and MEG3 (previously GTL2) genes are linked and reciprocally imprinted in several mammals, but their imprinting status is still unknown in pigs. In this study, we report polymorphisms, imprinting status and QTL analyses of the porcine DLK1 and MEG3 genes. Muscle and adipose DNA and RNA samples from 30-day-old animals generated with reciprocal crosses between the Korean native pig (KNP) and Yorkshire breeds were used to analyse DLK1 and MEG3 variation and expression. The samples exhibited paternal expression of DLK1 and maternal expression of MEG3 in pigs. These results indicated that the imprinting status of the DLK1 and MEG3 genes is conserved across mammalian species. By linkage analyses, we assigned the DLK1 and MEG3 genes to the telomeric region of SSC7. By QTL analyses, we confirmed a significant polar overdominance (POD) effect in DLK1, which was previously detected for several growth traits in pigs. However, no significant POD effect was found with the MEG3 locus. [source] First results on a relation between ovarian fluid and egg proteins of Salmo trutta and egg qualityAQUACULTURE RESEARCH, Issue 2 2007Franz Lahnsteiner Abstract By use of sodium dodecyl sulfate polyacrylamide gel electrophoresis, ovarian fluid proteins and main proteins of unfertilized eggs were qualitatively and quantitatively investigated in the brown trout, Salmo trutta, to see whether some of them were correlated with the rate of embryos reaching the eyed embryo stage. In the ovarian fluid, 12 types of proteins in the range of 39,166 kDa were detected whereby three proteins were lipoproteins and two were glycoproteins. Ovarian fluid proteins with a molecular weight of 85, 68, 62 and 39 kDa were negatively correlated with the percentage of eyed stage embryos. The statistical significance of the relations was low in simple and multiple regression models (R2,0.534) indicating that the relations were influenced and superposed by other factors. Therefore, ovarian fluid proteins give only poor information about maturity and quality of eggs. In the eggs, nine major types of proteins in the range of 95,15 kDa were identified. The 95 kDa protein was a lipoprotein, the 85 and the 62 kDa protein were glycoproteins, and the 15 kDa protein was a phosphoprotein. The 95, 85, 77 and 39 kDa protein were positively correlated with embryo survival to the eyed embryo stage. The explanatory effect of the multiple regression model was very high (R2=0.961) indicating that distinct egg proteins are closely related with egg quality. [source] Effects of four egg desticking procedures on hatching rate and further survival and growth of larvae in the tench (Tinca tinca L.)AQUACULTURE RESEARCH, Issue 6 2006Jose M Carral Abstract Four desticking procedures for tench eggs (A: tannic acid solution (1 g L,1) for 15 s; B: alcalase enzyme solution (8 mL L,1) for 60 s; C: alcalase enzyme solution (15 mL L,1) for 120 s; D: Woynarovich and Woynarovich (1980) solution for 58 min followed by tannic acid solution (1 g L,1) for 15 s) were tested to obtain data about influence on embryo survival to hatching stage and further survival and growth of the larvae. In the tannic acid and Woynarovich and Woynarovich (1980) treatment (A and D) few eggs stuck together and some were adhered to the incubator walls, whereas in the alcalase treatments (B and C) eggs neither stuck together nor adhered to the incubator walls. Percentages of hatched larvae did not show significant differences (mean values ranged between 47.4% in treatment A to 37.0% in treatment C). Larvae deformities observed were <0.5% in all cases. There were no significant differences among survival and growth rates of the larvae from different egg desticking origin, reaching, after 30 days, mean survival values around 90% and total length and weight of 12.5 mm and 19 mg respectively. [source] Effects of incubation temperature on development and yolk sac conversion efficiencies of spotted wolffish (Anarhichas minor Olafsen) embryos until hatchAQUACULTURE RESEARCH, Issue 11 2005Terje Sund Abstract Two egg batches of spotted wolffish, Anarhichas minor Olafsen, were incubated at 4, 6 and 8°C. Embryo samples were fixed and compared on each 100th daydegree until hatching (up to 1000 daydegrees). Embryos, yolk sacs and chorions were dissected and the sizes, wet and dry weights were recorded separately. Comparisons of gross morphologies and measured parameters showed increasing and generally significant differences with time between the incubation temperatures. Lower temperatures produced longer and more differentiated larvae at hatch with a smaller yolk sac. Even though some unexpected deviations were registered among batches and experimental groups, it was clear that temperature affected embryo survival and time of hatching. Overall survival was best at 6°C, in agreement with results from earlier studies. Yolk conversion efficiencies measured around the hatching point were generally high, ranging from 60% to 78%, varied between the two batches and probably reflected the developmental variations between embryos and larvae at the respective ages (daydegrees). The hatching process was apparently an energy-demanding period; yolk conversion efficiencies of unhatched embryos of similar age at each temperature were always higher. Temperature is one environmental factor that can be manipulated in hatcheries to induce hatching of viable larvae at an optimal stage of differentiation with respect to first-feeding success and early survival. [source] Isolation and characterization of a novel Xenopus gene (xVAP019) encoding a DUF1208 domain containing proteinMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 12 2007Xu Zhi Ruan Abstract We have identified a novel Xenopus gene (xVAP019) encoding a DUF1208 domain containing protein. Using whole-mount in situ hybridization and RT-PCR, we found abundant xVAP019 maternal transcripts in the animal hemisphere during the cleavage stages and blastula stages. During gastrulation xVAP019 is differentially expressed with higher levels in the animal helf and the highest in marginal zone, then further expressed widely at neuronal stages with strongest signals in the prospective CNS regions and the epidermal ectoderm. Subsequently xVAP019 was expressed predominantly in the head, the eyes, the otic vesicle, branchial arches, spinal cord, notochord, somites, and tailbud. It is absent or very weak in the endoderm. Injecting a morpholino oligo complementary to xVAP019 mRNA or injecting a caped xVAP019 mRNA caused most of embryos to die during gastrulation and neurulation. Overexpression of xVAP019 mRNA also led to eye defect, shorten interocular distance, small body size and abnormal pigment formation in parts of the survival embryos. Similar effects were induced by injecting the xVAP019 human homologous gene FAM92A1. Our results suggest that xVAP019 is essential for the normal ectoderm and axis mesoderm differentiation and embryos survival. This investigation is for the first time in vivo study examining the role of this novel gene and reveals an important role of xVAP019 in embryonic development. Mol. Reprod. Dev. 74: 1505,1513, 2007. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||