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PubMed1989

A simple method for shell-less cultivation of chick embryos.

The chorio-allantoic membrane of explanted chick embryos can be used for the study of vascular development and of the vascular response to drugs and to tissue implants or tissue extracts. Three different types of vials for shell-less cultivation of chick embryos were compared in terms of short-term survival. Plastic cups with rounded bottoms were superior to Petri dishes and polyethylene film bags, in that they combined a high survival rate of the embryos with a possibility of using a large number of embryos in each experiment. With the use of plastic cups this method is simple, reliable and inexpensive.

Allantois↗
PubMed2005

A pair of shelled eggs inside a female dinosaur.

An oviraptosaurian specimen (Dinosauria, Theropoda) from an Upper Cretaceous formation in China retains a pair of shelled eggs in the pelvis, providing direct evidence that oviraptorosaurian dinosaurs laid paired elongatoolithid eggs. The presence of the paired eggs suggests that theropod dinosaurs had two functional oviducts (like crocodiles) but that each oviduct produced only one egg at a time and that an entire egg clutch was laid through multiple ovipositions (like birds). The orientations of the eggs inside the skeleton and in clutches indicate that the mother came to the center of the nest to lay eggs.

Animals↗
PubMed1989

Changes in uterine fluid composition and acid-base status during shell formation in the chicken.

The aim of this study was to characterize the dynamic changes in uterine fluid composition and acid-base status during shell calcification in the chicken. Uterine eggs at timed intervals were manually aborted and the accompanying fluid collected and analyzed for composition of osmolytes, enzymes, and acid-base parameters. Blood samples were analyzed for comparison. No considerable change in blood gases took place in relation to residence time of the calcifying egg in the uterus. A significant acidosis occurred at latter stages. Only minor changes were revealed in plasma osmotic and biochemical composition throughout egg calcification. In contrast, major changes were revealed in uterine fluid composition and acid-base status during calcification. The most prominent phenomenon was the sharp increase in CO2 partial pressure, from 82.2 Torr at 0 h to 132.8 Torr at 10 h. As bicarbonate concentration remained almost stable, fluid pH dropped from 7.412 to 7.250 within this stage. Uterine fluid sodium and chloride concentrations and osmolality dropped significantly in the course of calcification, whereas potassium concentration significantly increased. A sharp increase in glucose, calcium, and magnesium concentrations was measured in the early stages of calcification. These findings are discussed in relation to existing models for transport mechanisms of the uterine epithelial tissue. The comprehensive picture that emerges from the present study should enable future application in establishing a self-contained culturing system in vitro for studies of embryonic development.

Acid-Base Equilibrium↗
PubMed1999

Biosorption of actinides from dilute waste actinide solution by egg-shell membrane.

Removal of radioactive elements from the effluent and waste aqueous solutions is an important problem. In previous laboratory batch experiments, hen egg-shell membrane (ESM) was stable as an insoluble protein and was very capable of binding heavy metal ions from aqueous solution. Batch laboratory pH profile, time dependency, and capacity experiments were performed to determine the binding of uranium (U) and thorium (Th) to ESM. Batch pH profile experiments indicated that the optimum pH for binding these actinides was approx 6.0 (U) or 3.0 (Th). The adsorption isotherms were developed at pH 5.0 (U) or 3.0 (Th) at 25 degrees C, and the adsorption equilibrium data fitted both Langmuir and Freundlich models. The maximum uptakes by the Langmuir model were about 240 mg U/g and 60 mg Th/g dry weight ESM. In addition, their adsorption capacities increased as salt concentration increased. ESM could also accumulate uranium from dilute aqueous solution by adjusting to the optimum pH. These results showed that ESM was effective for removing actinides from solution and would be useful in filtration technology to remove actinides from aqueous solution.

Actinoid Series Elements↗
PubMed1976

The effect of pharmacological levels of dietary vanadium on the egg production, shell thickness and egg yolk cholesterol in laying hens and coturnix.

The addition of 100 p.p.m. of vanadium to a ration for White Leghorn laying hens caused a significant increase (p less than 0.01) in the egg shell thickness, but did not cause any significant change in the production, egg weight or egg ypok cholesterol content. The addition of 300 p.p.m. of vanadium caused a severe depression in the egg production which was the only symptom of vanadium toxicity to be observed. The addition of 50, 100, 200 or 300 p.p.m. vanadium to the ration of laying coturnix did not cause any significant change in egg production, egg weight, or egg yolk cholesterol content. The addition of the same levels of vanadium to one-day old male coturnix chicks did not cause any significant growth depression or mortality. We suggest that coturnix may be more resistant to vanadium toxicity than chickens.

Animals↗
PubMed1980

Calcium-binding proteins in serum: quantitative differences between thick and thin shell lines of chickens.

Calcium binding by two proteins, vitellogenin and albumin, was measured in serum of a line of hens producing thick (THK) and a line of hens producing thin shells (THN) as well as a line of commercial hens using gel filtration in 45calcium buffer. Vitellogenin was quantitated in serum of THK and THN using a radial immunodiffusion test. Levels of serum calcium were measured and related to the above mentioned parameters. The binding of vitellogenin was significantly greater in 13 THK than 13 THN (672 vs. 508 cpm/ml X 10(-3), but binding by albumin was not significantly different between the two lines (386 vs. 344 cpm/ml X 10(-3). Binding in 11 commercial hens was similar to that for THN. The THK had significantly greater levels of diffusible, non-diffusible, and total serum calcium than THN. Significant positive correlations between total serum calcium and vitellogenin binding were found in THK (.77) and THN (.81) as well as in the commercial hens (.64). Like vitellogenin binding, levels of vitellogenin were significantly greater in THK than THN (4.0 vs. 1.8 mg/ml). These results suggest that in addition to having more diffusible and non-diffusible serum calcium, THK have more calcium binding and more vitellogenin to perform the binding function than THN.

Animals↗
PubMed1981

Pimpling of egg shells and hatchability in several strains of turkeys.

Eggs from several strains of turkeys (two randombred control populations of different origin and differing greatly in body weight and several sublines of these control strains selected for various traits) were scored for the amount of egg shell pimpling over a 12-week hatching period. The frequency of pimpled eggs averaged 15.6% in the medium-bodied strains and 21.2% in the large-bodied strains. The two randombred control strains, based on hen averages, did not differ significantly from each other, nor was there any significant difference among medium-bodied strains for pimpling scores. A large-bodied subline selected for decreased broodiness had a higher pimpling score than its corresponding randombred control. There were no other significant differences among the large-bodied strains. These data suggest that there is either little genetic variation in egg pimpling or little association between egg pimpling and traits for which selection was practiced (egg production, 16-week body weight, blood level of corticosterone after cold stress, clutch length, fertility, or plasma level of estrogens during the laying period). Pimpling increased with length of the hatching period. There was a small but significant correlation coefficient (-.11) between pimpling score and hatch of fertile-eggs. There was no significant association between pimpling score and percent 7-day incubation weight loss.

Aging↗
PubMed1983

The relationship between body weight loss during an induced molt and postmolt egg production, egg weight, and shell quality in caged layers.

Two trials were conducted to determine the relationship between percent body weight loss (% BWL) during an induced molt and postmolt performance. The molt was induced by fasting and photoperiod manipulation. Four groups with 24, 27, 31, or 35% BWL (Trial 1) or 20, 25, 30, or 35% BWL (Trial 2) were utilized in each trial. Performance was evaluated on the basis of 24 weeks of egg production and determinations of egg weight (EW), specific gravity (SG), and shell weight (SW) conducted during Weeks 8 (Trial 2 only), 18, and 24 following the removal of feed. The 27 and 31% BWL groups of Trial 1 and the 30 and 35% BWL groups of Trial 2 produced significantly more eggs per hen housed than the remaining treatments in their respective trial. Differences in SG and SW at the end of the trial were most pronounced in Trial 1 where the 27 and 21% BWL groups exhibited significantly greater SG and SW at Week 24 than did the 24 or 35% BWL groups. No significant differences occurred for SG at Week 24 of Trial 2, but the 35% BWL group exhibited significantly improved SW when compared to the 25% BWL group with the remaining groups intermediate. The EW was greatest for the 31% BWL and least for the 35% BWL group at 24 weeks in Trial 1 but did not differ in Trial 2. It was concluded that a body weight loss of approximately 27 to 31% produced optimum postmolt performance.

Animals↗
PubMed1983

Serum progesterone, enzymes, and electrolytes of hens laying a low or high incidence of shell-less eggs.

Three experiments were conducted to determine possible differences in serum progesterone, enzymes, and electrolytes between hens laying a high or low incidence of shell-less (SL) eggs. Blood was taken at time of oviposition and at 6, 12, 18, and 25 hr later, irrespective of the stage of the sequence. The results indicated no significant differences in average serum progesterone between hens laying a high or low incidence of SL eggs. In general, the patterns of serum progesterone in relation to time of oviposition was similar for each type. No significant differences were observed in serum phosphorus, magnesium, glutamate pyruvate transaminase, or alkaline phosphatase between hens laying a high or low incidence of SL eggs. It was concluded that the production of SL eggs is not related to abnormal serum progesterone, alkaline phosphatase, glutamate pyruvate transaminase, magnesium, or phosphorus levels.

Alanine Transaminase↗
PubMed1984

Increasing hatchability of turkey eggs by matching incubator humidity to shell conductance of individual eggs.

One of the most important factors determining hatchability of avian eggs is the proper water balance of the eggs during incubation. In turkey eggs, a total diffusive water loss (F) of 12 +/- 1% SD initial egg mass in 28 days, yielded maximal hatchability irrespective of the combination of eggshell water vapor conductance (G) and incubator humidity (PI), which brought about this water loss. A good correlation was found between G as obtained at the beginning of incubation and the final F in a given PI. The G in a random sample of 1256 fresh turkey eggs was normally distributed around the mean of 18.70 +/- 2.87 SD milligrams (100 g X day X torr)-1 (Coefficient of variation = 15.3%). The distribution of G in eggs with dead in the shell embryos had, in addition, two more peaks of G values [around 22.5 and 13.0 mg (100 g X day X torr)-1]. When eggs were sorted into low (less than 17), medium (17 to 20), and high (greater than 20) G categories, and incubated at low (19.4), medium (26.6), and high (33.9) torr PI, respectively, hatchability increased by a factor of 1.08. Poor hatchabilities were obtained in mismatching humidities and conductances. It seems that hatchability success may be experimentally improved if a correct rate of water loss is fitted to sorted eggs during incubation.

Animals↗
PubMed1984

Egg shell quality, medullary bone ash, intestinal calcium and phosphorus absorption, and calcium-binding protein in phosphorus-deficient hens.

The effect of dietary phosphorus deficiency on the performance and on various parameters of calcium, phosphorus, and vitamin D metabolism was studied in laying hens. Phosphorus deficiency resulted in a decline in rate of production and egg weight, probably through appetite depression. The latter, or any secondary calcium deficiency, does not appear to cause the observed reduction in shell quality due to the deficiency. Similar to the response in the chick, phosphorus deficiency resulted in an increase in calcium-binding protein in intestine and kidney, there was no change in the activity of kidney 25-hydroxy-vitamin D3-1-hydroxylase. Percentages of calcium and phosphorus absorption were also higher during phosphorus deficiency. Medullary bone ash, decreased during phosphorus deficiency, was probably due to a reduction in the rate of bone formation.

25-Hydroxyvitamin D3 1-alpha-Hydroxylase↗
PubMed1985

Shell quality as influenced by zeolite with high ion-exchange capability.

Sixteen dietary treatments applied to a total of 960 hens were used to determine the influence of zeolite A on shell quality and egg size. In Experiment 1, sodium zeolite A (SZA) was fed at three levels (0, .75, and 1.50%) in diets containing 4.0 and 2.75% calcium (Ca) for 8 weeks to old hens. In Experiment 2, the same levels of SZA were fed in diets containing two total sulfur amino acid levels (TSAA, .61 and .51%) to young hens for 12 weeks. Calcium zeolite A (CZA) was also fed at .68% in Experiment 1 in the 4.0% Ca diets and in Experiment 2 in the .51 and .61% TSAA diets. These diets were adjusted for sodium (Na) and chloride (Cl). SZA (.75% unadjusted for Na and Cl) was fed to old hens receiving the 2.75% Ca diet in Experiment 1. All diets were isocaloric and isonitrogenous within diets having the same Ca or TSAA level within an experiment. Response criteria were egg production, feed consumption, egg specific gravity, serum Ca, and body weight. A significant linear response in egg specific gravity occurred within 2 or 3 weeks, when diets supplemented with SZA were fed to old (Experiment 1) and young (Experiment 2) hens. Average Ca intake for control hens (Experiment 1) fed the 2.75 and 4.0% Ca diets was 2.93 and 4.54 g, respectively. Average Ca intake for control hens (Experiment 2) fed the .51 and .61% TSAA diet was 4.38 and 4.00 g, respectively. The CAZ (Experiments 1 and 2) and SZA (unadjusted for Na and Cl, Experiment 1) also gave significant increases in egg specific gravity. Zeolite A had little or no influence on egg weight, feed consumption, or egg production in Experiments 1 or 2. When Na and Cl were not adjusted in the SZA treatments (Experiment 1) a significant reduction in production occurred. It was concluded that zeolite A will significantly increase egg specific gravity and we hypothesize that the mechanism responsible for the significant improvement is related to the high ion-exchange capability of zeolite A.

Aluminum Silicates↗
PubMed1989

Effect of hatching egg sanitizers on embryonic survival and hatchability of turkey eggs from different lines and on egg shell bacterial populations.

Three experiments were conducted to examine the effect of hatching egg sanitizers on embryonic survival, hatchability, and microbiological populations of turkey eggs. Each experiment consisted of two trials. Experiments 1 and 2 were designed to examine embryonic survival and hatchability following sanitization. Experiment 3 examined postsanitization levels of bacteria on the shell surface and inside the egg at Day 7 of incubation. In Experiment 1, formaldehyde fumigation (FF) was compared to quaternary ammonium (QA). In Trial 1, eggs of 359 hens representing 10 lines were randomly assigned to one of the two treatments. In Trial 2, 3,890 eggs produced from a cross of randombred control line (RBC2) females with commercial sire line (C) males were randomly assigned to one of the two treatments. Differences due to sanitizing treatment were nonsignificant in both trials. Line was significant for 7-day embryonic survival and hatch of surviving embryos in Trial 1. In Experiment 2, QA was compared with QA plus U.S.P. Formalin (QAF). In Trial 1, eggs of 288 hens representing 10 lines were randomly assigned to one of the two treatments. In Trial 2, 1,058 eggs produced from the cross of RBC2 females with C males were randomly assigned to one of the two treatments. Differences due to sanitizing treatment were significant only for 7-day embryonic survival in Trial 2; embryonic survival was highest for QA. Line differences in Trial 1 were significant (P less than .01) for 7-day embryonic survival and hatch of surviving embryos.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Hematological indices of turkey embryos incubated at high altitude as affected by oxygen and shell permeability.

Turkey eggs (Meleagris gallopavo) were incubated at an altitude of 1,707 m to test the effects of oxygen supplementation and increased eggshell permeability by removal of shell cuticle on embryonic hematology. Turkey embryo hematological indices measured were red blood cell count (RBC), hemoglobin concentration, packed cell volume, mean cellular volume, mean cellular hemoglobin, and percentage of reticulocytes. Although hemoglobin concentration measured during pipping increased as expected by increasing RBC, no significant differences were observed between oxygenation, or permeability treatments, or their interaction. Under the high altitude conditions of the present experiment, increased hemoglobin concentrations in all treatments corresponded to increased numbers of erythrocytes with constant mean cellular hemoglobin. None of the remaining hematological indices examined was affected by oxygen or permeability treatments. It was concluded that turkey embryos incubating at 1,707-m elevation make no additional changes in hemoglobin concentrations during the plateau stage in oxygen consumption (25, 26, and 27 days of incubation) when exposed to increased oxygen tension (151 mm Hg versus 135 mm Hg) or increased eggshell permeability (19.9 mg H2O/day per mm Hg versus 23.2 mg H2O/day per mm Hg).

Altitude↗
PubMed1992

Inheritance of tinted eggshell colors in white-shell stocks.

The present study was conducted to study the genetics of tinted eggshell colors in two breeds of chickens laying white-shell eggs. Reciprocal crosses were made between an inbred White Leghorn line (ES) and an inbred Ancona line (ANC). The F1 birds were intercrossed and F1 females were backcrossed to each of the original lines. Eggshell color from each resultant group was measured using a Minolta chromometer, and a value (e) representing the color intensity adjusted by hue and saturation was used as the measurement criterion. Age, hatch group, and crosses each contributed significantly to the variation seen in eggshell color. Distribution comparisons indicated that two major autosomal loci affected the trait in these lines: one gene having incomplete dominance controls the amount of pigment deposition; the second completely inhibits pigment deposition when homozygous recessive. A test of goodness of fit supported this hypothesis. Genetic components were estimated by linear models. Epistasis, dominance, and additive effects contributed significantly to this trait. No sex-linked effects were noted.

Analysis of Variance↗
PubMed1996

Dietary marine algae promotes efficient deposition of n-3 fatty acids for the production of enriched shell eggs.

Two experiments were conducted to investigate the usefulness of a natural golden marine algae (MA) as a poultry ration supplement for the production of shell eggs rich in n-3 fatty acids (n-3 FA). This MA is unique due to a high concentration of docosahexaenoic acid (DHA; C22:6n-3) and the absence of other n-3 FA normally present in marine oils such as menhaden oil (MO). In the first experiment, 60 24-wk-old Single Comb White Leghorn (SCWL) hens were divided among four dietary treatments, including a typical corn-soybean control (CON); 1.5% MO, supplying 233 mg eicosapentaenoic acid (EPA) and 155 mg DHA per d; 2.4% MA, supplying 200 mg DHA/d; and 4.8% MA, supplying 400 mg DHA/d. A second experiment using 96 56-wk-old SCWL was conducted using the same diets. In both experiments, eggs were collected weekly for 4 wk for determination of egg production parameters and yolk FA content. Each week, yolk samples were extracted, methyl estered, and quantified using gas chromatography. Transient depression in egg and yolk weights were noted early in Experiment 1 in response to dietary 4.8% MA. Although egg and yolk weights were not affected in Experiment 2, egg production was significantly reduced in the 4.8% MA treatment. Egg production was unaffected due to diet or week in Experiment 1. In both experiments, yolk polyunsaturated profiles were significantly influenced by diet. Dietary n-3 FA supplementation significantly increased yolk total N-3 FA with concomitant reductions in yolk n-6 FA. Although hens fed MO were supplied predominantly EPA, the principal yolk FA deposited was DHA. Marine algae also promoted efficient yolk DHA deposition with the highest yolk DHA concentrations attained in eggs from hens fed 4.8% MA. These data indicate that utilization of MA as a direct source of dietary n-3 FA may provide an efficient alternative to current sources of n-3 FA available for the production of poultry products rich in n-3 FA.

Animal Feed↗
PubMed2000

Reduced oxygen diffusion across the shell of Gray gull (Larus modestus) eggs.

Gray gulls, Larus modestus, nest 1500 m above sea level in northern Chile's Atacama Desert, one of the driest in the world. Their eggshell gas permeability, one third of that found in other Larus species, is an adaptation that reduces water loss, but at the expense of oxygen diffusion into the air cell with resultant hypoxia and reduced metabolic rate. This contrasts with characteristics found in birds nesting at very high altitudes where oxygen diffusion across the egg shell is maximized at the expense of water conservation. The oxygen consumption (MO2) of Larus modestus is 66% that of Larus argentatus; the oxygen conductance (GO2) is equivalent to 48% of that obtained in 5 other bird species. The oxygen partial pressure (PAO2) in the air chamber of Larus modestus (84 Torr) is lower than that of 10 other bird species whose average (PAO2) is 106 Torr. The CO2 partial pressure (PACO2) in the air chamber of Larus modestus is 68 Torr, a higher value than that found in 9 other bird species whose average (PACO2) is 39 Torr.

Adaptation, Physiological↗
PubMed2004

Effect of thermoultrasonication on Salmonella enterica serovar Enteritidis in distilled water and intact shell eggs.

The combined effects of simultaneous application of ultrasonic waves and heat treatment (thermoultrasonication) on the survival of a strain of Salmonella enterica Enteritidis was studied in both distilled water and intentionally contaminated intact eggs immersed in water. Although minor differences were observed between parameters obtained for thermoultrasonic treatment of bacteria suspended in water and those attached to the shell egg, the thermoultrasonication effects were considered to be of the same level in the range of temperatures assayed (52 to 58 degrees C). This combined process presented a clearly higher killing effect than the heat treatment alone. It decreased the decimal reduction times (D-values) by 80 to 55%, respectively, in the range of temperatures for heat treatment when the organism was suspended in water, which means a 99.5% reduction (5D to >2D) of the original bacterial load versus a 90% reduction for the heat treatment alone. The practical implications of the phenomenon are discussed.

Animals↗