Temperature Adaptation of Embryonic Development Rate among Frogs

1972 ◽  
Vol 45 (3) ◽  
pp. 223-228 ◽  
Author(s):  
Ian A. McLaren ◽  
John M. Cooley
1990 ◽  
Vol 41 (5) ◽  
pp. 575 ◽  
Author(s):  
MJ Kokkinn

Mathematical relationships describing the effect of water temperature on embryonic development and generation time for Tanytarsus barbitarsis, a nuisance chironomid from salt lakes near Port Augusta, South Australia, were compared. The aim of the comparison was to determine whether the relation- ship describing egg hatching could be extrapolated to determine the overall development rate of the species. Results indicated that the power function that closely described embryonic development, D(t) = 8712.32t-2.70, could not be fitted to the generation-time data. However, when an additional term, water salinity, was included, a highly significant relationship was derived: D(s,t)*=S4.0308t-4.471. This suggested that laboratory egg-hatching experiments could not account for the attenuating effect of environmental factors on overall development rates in the field.


1975 ◽  
Vol 32 (3) ◽  
pp. 397-402 ◽  
Author(s):  
Wen-hwa Kwain

Lowest mortality rates of rainbow trout (Salmo gairdneri) embryos were obtained at temperatures of 7 and 10 C and light intensities of 0.2 and 20 lx. Temperatures of 3 and 15 C and an intensity of 400 lx were near the thresholds for development. Eggs exposed to 0.2 lx required 111 days to reach 50% hatch at 3 C, but 26 days at 15 C; those exposed to 20 lx, 97 days at 3 C and 25 days at 15 C.Growth rates of rainbow trout 145 days after hatch were significantly different (P < 0.05) at 10 and 3 C, and 20, 2, and 0.2 lx. The fastest growth occurred at 10 C and 2 lx, and the lowest growth at 3 C and 0.2 lx. For increment of body weight it was about 23.8%/day of initial weight and 6.6% at 3 C. At light intensities of 20, 2, and 0.2 lx, the rate per day was 24.7, 17.2, and 11.2%, respectively. However, increases in length occurred at a much reduced rate.Variations in numbers of vertebrae, gill rakers, and fin rays were positively correlated with the embryonic development rate. Longer incubation periods were usually associated with more meristic elements, regardless of the environmental factors involved.


2011 ◽  
Vol 7 (3) ◽  
pp. 425-428 ◽  
Author(s):  
Thomas E. Martin ◽  
Elena Arriero ◽  
Ania Majewska

Long embryonic periods are assumed to reflect slower intrinsic development that are thought to trade off to allow enhanced physiological systems, such as immune function. Yet, the relatively rare studies of this trade-off in avian offspring have not found the expected trade-off. Theory and tests have not taken into account the strong extrinsic effects of temperature on embryonic periods of birds. Here, we show that length of the embryonic period did not explain variation in two measures of immune function when temperature was ignored, based on studies of 34 Passerine species in tropical Venezuela (23 species) and north temperate Arizona (11 species). Variation in immune function was explained when embryonic periods were corrected for average embryonic temperature, in order to better estimate intrinsic rates of development. Immune function of offspring trades off with intrinsic rates of embryonic development once the extrinsic effects of embryonic temperatures are taken into account.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
P Guilherme ◽  
A Setti ◽  
D Braga ◽  
K Precipito ◽  
A Iaconell ◽  
...  

Abstract Study question In consecutive intracytoplasmic sperm injection (ICSI) cycles, is embryonic development in EmbryoScope better than the previous one obtained in a benchtop (G–185) incubator? Summary answer Embryonic development, and oocyte and embryo utilization rates (OUR and EUR) are significantly improved in the EmbryoScope, as compared to G–185. What is known already The time-lapse imaging (TLI) system, which allows a non-invasive continuous assessment of embryo morphokinetics parameters in a closed culture system has been developed, promising improved embryo development by reducing oscillations in pH, humidity and temperature. To investigate this hypothesis, one study has already compared embryonic development in a TLI versus a benchtop incubator. However, It has never been investigated whether embryonic development can be improved within-subject, by changing from benchtop incubator in the first intracytoplasmic sperm injection (ICSI) cycle to the EmbryoScope, a TLI incubator, in the following ICSI cycle, and that was the objective of the present study. Study design, size, duration This study had a retrospective within-subject design, in which each cycle served as its own control. Data were obtained via chart review of patients undergoing ICSI in a private university–affiliated IVF center that fulfilled the following criteria: second ICSI attempt in which embryos had been cultured in a TLI incubator system (TLI group, n = 71), preceded by a first ICSI attempt in which embryos had been cultured in a conventional incubator (Control group, n = 71). Participants/materials, setting, methods Embryonic development up to the fifth day of development, OUR (transferred embryos plus frozen embryos per retrieved oocytes) and EUR (transferred embryos plus frozen embryos per fertilized oocytes) were compared between the groups using generalized linear models followed by Bonferroni post hoc. The post hoc achieved power was 82.6%, considering the sample size, the effect size obtained for blastocyst development rate and 5% significance level. Main results and the role of chance There were significant differences in fertilization rate (76.0% ± 1.3 vs. 80.0% ± 1.4, p = 0.044, OR: 1.051, CI: 1.001 – 1.103), non-fertilization rate (14.8% ± 0.6 vs. 6.3% ± 0.4, p &lt; 0.001, OR: 0.424, CI: 0.370 – 0.486), day–2 non-cleavage rate (3.8% ± 0.2 vs. 1.1% ± 0.1, p &lt; 0.001, OR: 0.285, CI: 0.234 – 0.347), blastocyst development rate (40.9% ± 1.1 vs. 55.6% ± 1.3, p &lt; 0.001, OR: 1.358, CI: 1.267 – 1.456), frozen blastocyst rate (31.8% ± 0.8 vs. 37.0% ± 0.9, p &lt; 0.001, OR: 1.163, CI: 1. 085 – 1.248), OUR (40.7% ± 1.0 vs. 50.2% ± 1.1, p &lt; 0.001, OR: 1.232, CI: 1.155 – 1.314), and EUR (52.4% ± 1.1 vs. 66.6% ± 1.2, p &lt; 0.001, OR: 1.269, CI: 1.202 - 1.341), all in favor of TLI group. Pregnancy rate (30.2% vs. 30.8%, p = 0.940), implantation rate (24.6% ± 40.0 vs. 26.1% ± 41.6, p = 0.830), and miscarriage rate (21.1% vs. 15.0%, p = 0.622) were similar between Control and TLI groups, respectively. Limitations, reasons for caution (i) Different culture dishes were used in each system; (ii) it is not possible to confirm how much of the embryonic improvement was due to the culture conditions; (iii) the study design is not ideal for the comparison of clinical outcomes and, also, underpowered to do so. Wider implications of the findings: Even though the clinical outcomes were similar between the groups, the results may also lead to higher cumulative pregnancy outcomes following embryo thawing and transfer. Trial registration number Not applicable


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4297
Author(s):  
Luciana Simões Rafagnin Marinho ◽  
Lain Uriel Ohlweiler ◽  
Marcos Henrique Barreta ◽  
Paulo Bayard Dias Gonçalves ◽  
Joana Claudia Mezzalira ◽  
...  

<p>Conjugated linoleic acid (CLA) might be able to improve the cryotolerance of <em>in vitro-</em>produced (IVP) embryos. The effect of two CLA isomers on the cryotolerance of bovine IVP embryos, as well as that of the stage of embryonic development and the method used for cryopreservation was evaluated by three experiments. In Experiment 1, oocytes (n = 3,917) were fertilized <em>in vitro </em>and cultured with 0, 50, 100, or 200 ?M <em>trans-</em>10<em>, cis-</em>12 (t10, c12 CLA). In Experiment 2, fertilized oocytes (n = 2,131) were cultured with 100 ?M t10, c12 or <em>cis-</em>9<em>, trans-</em>11 (c9<em>, </em>t11 CLA), or a combination of both isomers. The embryos were vitrified at the blastocyst (BL) or the expanded blastocyst (EB) stage. In Experiment 3, oocytes (n = 1,720) were fertilized and cultured with or without 100 ?M t10, c12 CLA, and the blastocysts were vitrified or frozen. Blastocyst development rate as well as the rates of re-expansion and hatching after thawing was recorded. Moreover, the mean cell number and mRNA expression of acetyl-CoA carboxylase (ACC1) and stearoyl-CoA desaturase (SCD1) as well as fatty acid synthase (FASN) multienzyme complex were determined. In Experiment 1, the highest concentration of t10, c12 CLA that did not reduce blastocyst development rate was 100 ?M. In Experiment 2, the rates of re-expansion and hatching among the EBs obtained through IVP after supplementation with t10, c12 CLA (73.1% and 57.7%), with c9, t11 CLA (80.0% and 68.6%), with the combination (78.3% and 52.2%), and with the control group (85.4% and 58.3%) were similar. At the BL stage, the rates of re-expansion and hatching were lower than those at the EB stage, and CLA combination allowed a hatching rate (8.0%) lower than that observed in the control group (40.0%). In Experiment 3, the hatching rates for vitrified EBs (vitrified control; 67.4%) and vitrified CLA EBs (65.8%) were higher than those obtained for frozen EBs, exposed (13.3%) or not exposed (28.6%) to CLA. In addition, in Experiment 3, the hatching rate was higher at the EB stage in vitrified groups, while the rates of BL and EB were similar in frozen groups, thus proving that vitrification was more efficient than freezing for IVP bovine embryos. In Experiment 3, CLA isomer t10, C12 did not influence the embryonic cell number or mRNA expression of ACC1 and SCD1 enzymes, but decreased the mRNA expression of FASN. In conclusion, 100 ?M CLA did not affect subsequent embryonic development. However, neither CLA isomer improved the cryotolerance of IVP bovine embryos.</p>


Sign in / Sign up

Export Citation Format

Share Document