Changes In Hatchability Research Articles

Short exposure of Artemia salina to group-12 metals: Comparing hatchability, mortality, lipid peroxidation, and swimming speed

The hatchability, mortality rate, lipid peroxide levels, and swimming speed of Artemia salina have been compared based on short exposures of ZnCl2, CdCl2, and HgCl2 in artificial seawater. The hatching tests were carried out for 12, 24, 36, and 48 h at 28 °C. Mortality rate and lipid peroxide (LPO) levels were determined after 24 h of exposure at 28 °C, in the dark, and on living larvae using the FOX method. The swimming speed was determined after 24 h using a microcomputer coupled to a digital camera, with simultaneous treatment of the recorded images every 25 s, at 25 °C, under red-light irradiation. Results showed that Zn caused a gradual inhibition of the hatching for concentrations <900 µmol L−1; however, Cd and Hg displayed almost complete inhibition for concentrations ≤100 µmol L−1. Also, the heavy metals caused a dose-dependent increase of mortality (LD50) in the following order: Zn = 3290 µmol L−1 < Cd = 2206 µmol L−1 < Hg = 15.6 µmol L−1. Furthermore, significant LPO levels were found for Cd (1500–2000 µmol L−1, p < 0.001) and Hg (5–20 µmol L−1, p < 0.001). Finally, the swimming speed values increased significantly, for Zn ≈ 2.5 mm s−1 (1500 µmol L−1, p < 0.001), Cd ≈ 3.5 mm s−1 (2000 µmol L−1, p < 0.05), and Hg ≈ 4.0 mm s−1 (15 µmol L−1, p < 0.05), after 24 h exposure. There is a clear dose-dependent toxicity, indicating that Zn, Cd and Hg can induce significant changes in hatchability, mortality, and ethological and biochemical parameters.

Efficacy of the hatching event in assessing the embryo toxicity of the nano-sized TiO2 particles in zebrafish: A comparison between two different classes of hatching-derived variables

The aim of the present study was to evaluate the nano-TiO2 toxicity to zebrafish embryos through evaluating the success in hatching in relationship with hours post-exposure instead of considering just the total hatching rate. Zebrafish embryos 4h post-fertilization were exposed to nTiO2 (0, 0.01, 10, and 1000µgmL−1) for 130h. The hatching rate (HR) was calculated for each concentration (treatment). The HR magnitude was significantly (p<0.001) correlated (using simple regression) to hours post-exposure time interval (hpe; 34, 58, 82, 106, and 130), noted as HR.hpe. The HR descriptive statistics (HRds) and the parameters of the regression models (i.e., constant, x, F, and r2) were recruited to define 15 HRds- and 4 h.hpe-derived variables, respectively. The efficacy of the variables was evaluated. Exposure to nTiO2 led to a significant: premature hatching and general decrease in time required for normal hatching; and change in HR and hpe interrelations in a dose-dependent manner. The major change in hatchability between the treatment and control occurred at 58 hpe (62 hpf), when the treatment with nTiO2 induced significant premature hatching compared to only 6% of the hatched embryos in the control at the same time point. EC10 and EC50 values that cause premature hatching at 58 hpe for nTiO2 are 0.073µgmL−1 and 107.2µgmL−1 respectively. In general, this study shows multivariate differences among exposure concentrations of nTiO2 recruiting hatching-derived endpoints.

Laboratory Hybridization Between the Introduced and the Indigenous Green Lacewings (Neuroptera: Chrysopidae:Chrysoperla) in Japan

Abstract We report on laboratory hybridization between the indigenous Chrysoperla nipponensis and its close relative, C. carnea, which has been imported since 2001 from Germany to Japan as a biological control agent. Interspecific hybrids were obtained, and fully viable and fertile F1 and F2 generations were produced. Crosses between C. carnea females and C. nipponensis males showed 41.3% fertility, but the reciprocal cross showed only 9.5% fertility. Despite the low fertility of interspecific crosses, most F1 hybrids were fertile and were successfully backcrossed to both parental species. However, F1 males from C. carnea females × C. nipponensis males showed low fertility (zero except for 20% in one case) when crossed with any females (F1 or backcross). In the one combination resulting in 20% fertility, an extremely long preoviposition period was observed, caused presumably by a mating delay. The absence of change in hatchability, adult emergence rate, total developmental period, or deviation from the 50...

Effect of Aluminum on Performance and Mineral Metabolism in Young Chicks and Laying Hens

This study was performed to determine the long-term effects of dietary aluminum on egg production and reproductive parameters in the mature laying hen and on growth rate and feed efficiency in young chicks. The diets used in these studies were adequate in phosphorus and other essential nutrients. Aluminum added to constitute 0.30% of the diet severely depressed growth and reduced feed efficiency, bone ash and plasma phosphorus in male Ross x Leghorn chicks. At the same time, 0.15% added aluminum mildly depressed growth, feed efficiency and bone ash but had no effect on plasma phosphorus levels. The reduction in bone ash was relatively mild, and no clinical signs of rickets were observed. In laying hens, diets containing 0.15% added aluminum did not affect egg production, but 0.30% added aluminum reduced production significantly. Long-term exposure to aluminum increased percent shell in both groups receiving aluminum, whereas egg weight remained similar to that in controls. There were no changes in hatchability or bone ash associated with dietary aluminum. Although dietary aluminum influenced bone aluminum content, egg aluminum content was not affected. These studies indicate that dietary aluminum interferes with systems in addition to phosphorus metabolism.

Effect of a Quaternary Ammonium Sanitizer for Hatching Eggs on Their Contamination, Permeability, Water Loss, and Hatchability

The present study tested the biocidal effectiveness of the quaternary ammonium Hatching Egg Sanitizer Spray® (HES Spray®) in disinfecting broiler hatching eggs and in terms of its effects on eggshell permeability, water loss, and hatchability. The application of HES at a 1.5% or a 3.0% concentration resulted in significant reductions in the total aerobic counts on the egg surface of 98.1% and 99.9%, respectively, within 30 min of application. Molds and yeasts were significantly reduced by 3.0% HES at 14 days of incubation.Significant reductions in total aerobic counts on the egg surface due to 1.5% and 3.0% HES were also observed on eggs that were allowed to “sweat.” The 3.0% HES concentration also reduced coliforms on egg surfaces.Hatchability of fertile eggs from a 32-wk-old flock was significantly increased, over 6.0%, by spraying 1.5% or 3.0% HES in comparison to controls that were not sprayed, with no significant difference in hatchability due to treatment observed in eggs from flocks that were 36, 42, 46, or 62 wk of age. This change in hatchability associated with spraying HES may be due to a change in eggshell permeability (respiration) caused by an interaction of HES with the eggshell cuticle.

The fecundity and fertility of Medaka exposed to chronic gamma-radiation in their embryonic stages.

Eggs of the medaka, Oryzias latipes, were irradiated continuously with 137Cs γ-rays at exposure-rates of 10, 100 and 1000 R/day from the morula stage to hatching. Newly hatched fry were transferred to non-irradiation field. At one year after hatching medaka were tested for their fecundity and fertility. When irradiated females were mated with unirradiated males, both the total number of oviposition and number of eggs per oviposition decreased with increasing exposure-rate, whereas almost all the eggs laid were fertilized. However, a decrease in the hatchability of these “normal” eggs was observed in groups of 100 and 1000-R/day exposure-rate. When irradiated males were mated with unirradiated females, an increase in the number of abnormal eggs was obtained in groups of 100 and 1000-R/day exposure-rate, whereas no changes in both the total number of oviposition and number of eggs per oviposition were observed. No change in hatchability of the eggs in this group was also observed even when the highest exposure-rate, i.e., 1000 R/day, was applied.

Changes in fitness traits associated with selection for divergence in yolk cholesterol concentration.

1. Correlated changes in egg production, hatchability, egg weight, age at sexual maturation and body weight of lines selected for divergence in yolk cholesterol were studied in two different populations. 2. Divergence in yolk cholesterol resulted in a highly significant difference in percentage egg production with a negative correlation between yolk cholesterol and egg numbers. However, the calculated total daily mass of cholesterol excreted into the egg was similar in both lines. 3. These results indicate that the physiological mechanism by which these populations responded to selection pressure on the concentration of cholesterol in the yolk was by changing egg numbers rather than total amount of cholesterol excreted. 4. Body weights of the high and low yolk cholesterol lines of the meat type, but not of the layer‐type populations, were significantly different. After four generations the line selected for low yolk cholesterol from the meat‐type population weighed 80% of the line selected for high yolk cholesterol levels. 5. Sexual maturity and egg weight were also significantly different between the high and low yolk cholesterol lines, but these differences could not be related to selection response. No changes in hatchability between the cholesterol lines were observed.

Interspecific competition between Drosophila melanogaster and D. simulans: Effects of adult

The hatchability of eggs laid by D. simulans st and D. melanogaster Or-R-C in consecutive 12-hour periods was measured for the first seven days post eclosion in a replicated experiment where adult density at six levels, species frequency at two levels, and 32P tissue content at two levels were varied factorially. A similar experiment was done for D. simulans st and D. melanogaster yw. In both experiments, all unhatched eggs were classified as either dead or infertile. Least-squares analyses of variance on arcsine-transformed percentage data indicated that the three strains produced significantly different proportions of hatched, dead, and infertile eggs. Increased adult density significantly decreased the proportion of hatched eggs (and increased the proportion of dead eggs) for D. simulans st and D. melanogaster Or-R-C, but not for D. melanogaster yw. Effects of strain frequency were not significant for D. simulans st or D. melanogaster Or-R-C, but for D. melanogaster yw higher hatchability and lower proportions of infertile eggs were obtained in pure populations. Hatchability varied between periods; changes in hatchability being random (but significant) for D. melanogaster yw, and consistent (but not significant) for D. simulans st (a decrease in hatchability with time) and D. melanogaster Or-R-C (an increase with time). The competing strain of D. melanogaster did not influence the proportions of hatched, dead or infertile eggs from D. simulans st.

魚類の生殖せんおよびはい発生に対する放射性核種の影響

In this short review, the abnormal embryogenesis, and the changes in hatchability of eggs and in gonads of fish kept in contaminated water with radionuclides are dealt with.Many reports on the effects of radionuclides on the hatchability of fish eggs have been published. However, there is a marked divergence among these results. In our experiments, the process of embryogenesis was rather radioresistant, when eggs were irradiated with internal radiation from radionuclides incorporated into the eggs. It has been shown from estimation of absorbed dose that insufficient size of dose to produce low hatchability was given to the embryos during their embryogenesis. The damage of the gonads of fish was observed when fish was kept in water containing such low concentration of radionuclides that normal embryogenesis proceeded. It seems that the gonad of fish is a critical organ for the assessment of the effect of radionuclides on the fish population.

Photoacceleration of development in chick embryos

1. 1. Continuous illumination of White Rock eggs caused a significant reduction in incubation period when compared to eggs incubated in darkness. There was no change in hatchability. 2. 2. The most pronounced influence was observed when exposure to light was during the first week of incubation. Only 10 hr of incubation were required to demonstrate the accelerated development of eggs incubated in light. 3. 3. Air cell temperatures were the same for eggs incubated in light and dark suggesting that the phenomenon observed is due to light rather than temperature.

The influence of turning on the hatchability of hens' eggs II. The effect of turning frequency on the pattern of mortality, the incidence of malpositions, malformations and dead embryos with no somatic abnormality

Reasons were sought for the changes in hatchability associated with varying frequency rate observed in part I and by other workers. All deadin-shell from the hatches of part I were examined and classified into a number of categories. Their varying incidence in relation to the control hatches was taken to indicate the effect of the rates of turning investigated, viz. 0, once in 2 days, 2, 6, 12, 24 (control), 48, 96, 144, 192 and 480 turns per 24 hr. to the end of the 18th day of incubation.At the observed optimum rate of turning (96x) mortality was reduced throughout the incubation period with the greatest reduction occurring towards the end; the incidence of malpositions and malformations was reduced as was the case of embryos with no obvious cause of death.The observed decrease in mortality and hence increase in hatchability at the optimum rate of turning was attributed mainly to the probable improvement of the embryo's physiological environment.

Influence of Age of New Hampshire Female Breeders Upon Hatchability of Eggs

It is quite definitely established that the hatching quality of eggs laid during the second laying year is lower than that of the first year. Observation and results reported by Hays and Sanborn (1924), Warren (1934), Funk (1934), and Insko, Lowry and Caldwell (1951) indicate that there can be no doubt that the hatching quality of eggs laid during the first laying year is to a slight but significant degree superior to the hatching quality of those produced during the second year of production.Published data pertaining to changes in hatchability during the first year of production are limited. Insko, Steele and Wightman (1947) reported that first-year embryonic mortality was definitely lower for pullets in progressively older age-groups, and that essentially the same relationship applied to any one week for the respective years. Hays and Talmadge (1949) concluded that, in general, pullets are likely to show a decline in hatchability …

Observations on the relationship between riboflavin, hatchability and clubbed down

A brief account is given of the accepted view that riboflavin supplements in the diet of breeding stock lead to improved hatchability and that clubbed down is specific for a deficiency of this vitamin. Attention, however, is drawn to the apparent failure of various workers to achieve a hatching rate with a riboflavin supplemented diet substantially in excess of 80% of fertile eggs which appears to be the national average figure. An experiment is described in which range managed breeding stock received diets supplemented with riboflavin at varying levels, the lowest of which, in the light of available evidence, would be sufficient for good hatchability having regard to the riboflavin obtained by the stock from grass and their own droppings. The hatching rate of fertile eggs was maintained at about 80% with all rations and little change took place consequent on changing over from high to low or vice versa. Only a very small improvement was observed with a very high level of riboflavin. It is therefore concluded that either a figure around 80% hatchability represents the maximum influence of riboflavin on hatching rates or that there are generally other factor(s) present (or absent) in the embryo that prevent a higher rate being achieved. The evidence submitted suggests that this factor may be B12 or more probably, one of the unidentified factors in the A.P.F. complex, and that for hatching rates materially above 80% the A.P.F. complex must be increased above the levels presently supplied to range managed breeding stock, or the high hatching rates induced by high levels of riboflavin may greatly increase the birds' requirements for this factor(s) to a level well above that normally necessary.Attention is also drawn to the incidence of clubbed down among dead-in-shell with varying levels of dietary riboflavin. It is concluded that the presence of this embryonic abnormality is rapidly and almost completely influenced by changes in the level of dietary riboflavin and that these changes take place much more rapidly than changes in hatchability, once a moderately high hatching rate has already been reached. It is also contended that high riboflavin levels will almost eliminate the incidence of clubbed down, although an already moderately high hatching rate will remain unaffected. For this reason it is argued that the presence of clubbed down in some dead-in-shell is no conclusive evidence that an improvement in hatchability will follow supplementation of the diet with riboflavin unless the hatching rate is below average.

Effects of X-Rays on Hatchability and on Chromosomes of Habrobracon Eggs Treated in First Meiotic Prophase and Metaphase

A. Unlaid Habrobracon eggs x-rayed in late metaphase. I and allowed to develop parthenogenetically (1) Show a linear decline in hatchability from 50 r to 1,400 r, approximately the lethal dose. (2) Show no change in hatchability percentages with aging after treatment, time-intensity differences or fractionation of dose. (3) Continue meiosis and early cleavage after doses several times lethal, at rates not noticeably different from controls. (4) Show fragments but no bridges in division I, bridges, fragments or both in division II, fragments and bridges in cleavage. (5) Give a curve expressing dose-percentages of eggs without fragments which at high doses converges toward the dose-hatchability curve. (6) Show a number of fragments per treated egg which varies as the 0.94 power of dose between 500 r and 1,000 r, 0.53 power between 1,000 r and 1,500 r, and 0.58 power between 1,500 r and 2,000 r. B. Unlaid eggs x-rayed in prophase I and allowed to develop parthenogenetically (1) Give hatchability percentages equal to or higher than controls from 50 r to 750 r. (2) Show a decline in hatchability from 1,000 r to 44,800 r, approximately the lethal dose. (3) Give a hatchability curve which appears to be linear at low doses and to become "mixed" at high doses. (4) Show no significant change in hatchability in preliminary test of time-intensity differences but an increase with fractionation of dose. (5) Continue meiosis and early cleavage at lethal dose at rates not noticeably different from controls. (6) Show fragments and bridges in division I, either or both in division II, fragments and bridges in cleavage. C. Unlaid eggs treated in either stage (1) Show no change in hatchability when fertilized by untreated spermatozoa. (2) Develop as far as blastoderm in about twenty per cent. at approximately lethal doses. D. It can be concluded that (1) Consistent and correlated cytological and hatchability patterns of eggs treated in late metaphase I appear to prove conclusively that death is due to chromosome breaks arising from single hits. (2) Consistent differences in cytological effects and in nature of dose-hatchability curves correlated with consistent differences in stages of chromosomes at time of treatment argue strongly for the dependence of ionization effects upon the physical (or chemical) condition of the chromosomes. (3) High sensitivity of metaphase I, the stage in which tensions of chromosomes have been considered very high, argues strongly for the dependence of ionization effects upon the tension of chromosomes. Other suggestions made to explain differential sensitivity of chromosomes in different stages do not apply to material used in this study.