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PubMed1996

Effect of retinyl acetate, ascorbic acid and tocopherol supplementation of the feed on egg vitamin A content in Japanese quail.

The ration fed to laying Japanese quails was supplemented either with retinyl acetate (RA) (50 x 10(3) IU/kg, group A), ascorbic acid (500 mg/kg, group C), or with both substances in combination with each other (group AC) and with tocopheryl acetate (37.8 IU/kg; groups AE and ACE). On days 1, 8, 14, 20 and 28, some quantitative parameters of eggs (mass of egg-shell, albumen and egg yolk, retinoid content of egg yolk) were measured. The egg production parameters were not significantly affected by the supplementations. By the end of the second week, the total vitamin A (retinyl esters + retinol) concentrations of the egg yolk were significantly higher in the groups receiving supplemented feed (AC, AE and AEC) than in the control group. Two weeks later (on day 28), the vitamin A levels were elevated significantly in all groups except the group treated with ascorbic acid. From the point of view of vitamin A fortification of the egg yolk, the combined supplementations (groups AC, AE, AEC) seem to be more effective. The results indicate that vitamin A content of the egg yolk can be increased by a short-term RA supplementation of the laying ration. The retinoids present in the natural substances of eggs could possibly be a good source of vitamin A for humans.

Animal Feed↗
PubMed1986

Influence of time of calcium intake on bone and dietary calcium utilization.

Sixteen hens, 67 weeks old, having oviposition times at 0700 +/- .25 hr, were used in Experiment 1. Hens were randomly divided into two treatments and fed a .08% calcium diet following oviposition. For 5 days, at either 0800 (AM) or 1600 (PM) hours, hens received 3.65 g of calcium by intubation. On Day 1, the calcium source contained 25 microCi of calcium-45 (45Ca). Eggs and excreta were collected daily for 45Ca analysis. Experiment 2 was similar to Experiment 1 except that 34-week-old hens were used. Calcium-45 activity of the egg shell, excreta, serum, and total contents of the gastrointestinal (GI) tract was determined. Results of Experiments 1 and 2 indicated that hens receiving their daily supply of calcium in the PM deposited significantly more of that day's dietary calcium on the following day's egg than hens receiving calcium in the AM. Excreta from the AM-treated hens contained significantly more 45Ca than that from the PM-treated hens during the first 24 hr in both experiments. In Experiment 2, the quantity of 45Ca in serum and GI tract contents was significantly higher from hens in the PM treatment. It was concluded that hens utilized significantly more calcium for egg shell formation from PM consumption rather than AM consumption and, therefore, were less dependent on bone reserves when the calcium was consumed in the PM.

Animals↗
PubMed1985

Comparison of dwarf and normal broiler breeder hens.

Two strains of dwarf and two of normal broiler breeder hens were compared during the laying period for the following production parameters: egg number, hen-day and hen-housed egg production, mortality, feed consumption, egg weight, egg shell quality, hatchability, and fertility. Though the dwarf hens matured earlier, the number of eggs produced during the laying period did not differ (P less than .05) from that of the normal hens. The dwarf hens consumed 25.6% less feed per dozen eggs but produced smaller eggs. Mortality was higher for the dwarf hens during the laying period than for normal hens. The normal hens had an advantage over the dwarf hens in percent hatchability of all eggs set and percent fertility, but the percent hatchability of fertile eggs did not differ between the two genetic groups. No differences were found in egg shell quality of the two groups of chickens.

Animal Feed↗
PubMed1980

A method for the demonstration of pores in calcified eggs of vertebrates and invertebrates.

Determination of pore number, pore size as well as pore canal distribution is important in understanding the biology of calcified eggs among vertebrates as well as invertebrates. Various techniques have been applied to elucidate pore structure of avian egg shells, including fracturing coupled with scanning electron microscopy and differential histochemical staining of the matrix. The best results reported have thus far been from plastic impregnated, etched specimens (Board & Tullett, 1974). The present report is a modification of this latter technique, utilizing the very low viscosity, highly penetrating electron microscopic embedding medium developed by Spurr (1969). This modification is used in this report of the previously undescribed pores from the egg shells of the giant South American land snail, Strophocheilus oblongus. These eggs, which can be up to 50 mm in length, have recently been investigated with respect to the calcium carbonate mineralogy (Tompa, 1976) as well as with respect to the matrix biochemistry Tompa et al., 1977). (Similar resin has been used successfully for the plastic impregnation and ultrathin sectioning of that region of the snail shell where the body muscles insert into the shell comumella (Tompa & Watabe, 1976).) This technique, which can be utilized on avian eggs or on any other calcified material in probing for pores, relies on the high penetrating ability of the resin as well as on its easy commercial availability around the world.

Animals↗
PubMed2000

Evaluation of application methods for control of Aspergillus fumigatus proliferation on the air cell membrane of in ovo injected broiler eggs.

Three different techniques of applying fungicides and mold inhibitors were evaluated as control methods for Aspergillus fumigatus proliferation on the air cell membrane of eggs that were infertile or contained early dead embryos following in ovo egg injection. A controlled Aspergillus challenge model was utilized that simulates the natural occurrence of fungal growth following in ovo egg injection. Methods of application examined were egg shell spray, direct air cell application prior to Aspergillus challenge, and micro-aerosol fogging in the incubation compartment during Aspergillus challenge. Fungicides and mold inhibitors used included propionic acid, propionic acid plus ammonia, phenol, quaternary ammonium plus organic tin, hydrogen peroxide, enilconazole, and an aromatase inhibitor. When applied as egg shell spray treatments or micro-aerosol fog treatments, none of the products that were tested significantly reduced the incidence of mold proliferation on the air cell membrane when compared with untreated, but otherwise challenged, controls. When applied directly to the air cell membrane prior to fungal challenge, only enilconazole and the aromatase inhibitor significantly reduced the incidence of fungal proliferation when compared with appropriate controls.

Aerosols↗
PubMed1993

[Processes connected with hatching of larvae from eggs of parasitic nematodes].

Influence of such factors as temperature, pH, CO2 level and oxidation- reduction potential value in the alimentary tract of host on the stimulation of invasive eggs was studied. Changes of these factors lead to change in permeability of inner layer of egg-shell. Then the hatching fluid is released and its enzymes digest the egg-shell. In the nematodes, which have the free-living larvae, the initiation process can depend on parasite or environmental agents.

Animals↗
PubMed2001

Reaction between albumen and 3,3',5,5'-tetramethylbenzidine as a method to evaluate egg freshness.

The 3,3',5,5'-tetramethylbenzidine colorimetric test is proposed as a method for the evaluation of shell egg freshness. A simplification of the original method was tested on albumen, and the modified method was used to study the development of albumen-tetramethylbenzidine reaction in eggs stored at three temperatures for different times. The stability of the reagent solution and the repeatability of the analytical method were also studied. The reaction mechanism showed the predominant role of iron ions on the colorimetric response, and the secondary role of copper ions added to the reaction mix in order to enhance the response. The response coefficient of variation, due to the natural variability in eggs laid by hens of two breeds and different ages, was 10.3%, which is similar to the value obtained for furosine, but lower than those previously observed for other egg freshness indices such as Haugh Unit and air-cell height.

Animals↗
PubMed1982

The effect of lactose supplementation and source on feed intake and production characteristics of laying hens.

Three experiments involving a total of 550 laying hens were conducted to study the effects of low level lactose feeding on the egg production characteristics of laying hens. The specific purposes were to determine if lactose influenced calcium utilization and feed intake and if there were any important interactions between lactose and calcium. There was a consistent significant improvement in egg shell breaking strength as a result of lactose supplementation. One percent dietary lactose appeared to be adequate to achieve this improvement. The addition of 2 or 3% lactose did not result in any greater improvement than 1%. There were no consistent influences of lactose, lactose source, or calcium level on feed intake or any of the other variables examined in the three experiments. As was expected, 61-week-old hens laid significantly fewer and larger eggs with weaker shells than 47-week-old hens. There were four statistically significant interaction effects: lactose level X calcium level on egg production; lactose level X calcium level on egg shell strength; and age X lactose level on egg shell strength. Even though these effects were statistically significant, it is questionable whether or not they are of practical importance in feeding laying hens.

Animals↗
PubMed2006

A study on the interaction of xylanase and phytase enzymes in wheat-based diets fed to commercial white and brown egg laying hens.

A trial was conducted to investigate potential interactions between phytase and xylanase enzymes in wheat-based laying diets. Hens (480 ISA-White and 480 ISA-Brown) were distributed into 160 experimental units and fed one of 10 diets containing 75 to 77% wheat from 33 to 64 wk of age with a diet change at 49 wk. Two diets were adequate in P content (0.3 and 0.25% available P in the 2 phases) with or without xylanase (0 or 2,000 U/kg; Avizyme 2300, Danisco Animal Nutrition, Marlborough, Wiltshire, United Kingdom), and 8 diets had reduced P (0.2 and 0.15% available P) with or without xylanase and phytase (0, 300, 500, and 700 ppu/kg; Phyzyme 5000G, Danisco Animal Nutrition). Egg production was higher for ISA-Brown than for ISA-White hens, and ISA-Brown hens were larger. Eggs from ISA-Brown hens had lower albumen height; higher egg, shell, and albumen weights; and lower yolk weight than those from ISA-White hens. Egg production was not affected by the diet. In P-reduced diets without xylanase, phytase significantly increased BW gain in the first period with no change in feed intake or feed efficiency. In P-adequate diets, xylanase increased egg and albumen weight and albumen height. In P-reduced diets with xylanase, increasing levels of phytase increased egg and albumen weight. This trial demonstrated no negative interactions between these enzymes for production traits and no interactions between the diet and strain of hen. These data suggest that poultry producers can use these enzymes individually or together in feed for the Brown and White egg layers used in this study without concern for the strain of hen.

6-Phytase↗
PubMed2000

Variations of manganese in the eggs of the Norway lobster, Nephrops norvegicus (L.).

The Norway lobster, Nephrops norvegicus, lives on sediments rich in manganese (Mn). Temporal fluctuations of Mn in the eggs of N. norvegicus was investigated, both in the field and in laboratory experiments. Female gonads and external eggs of different developmental stages were measured for Mn. The Mn concentration during oocyte maturation and throughout most of the embryogenesis (after fertilisation) remained stable around 5 µg Mn g(-1) dry wt. egg. At the end of the embryonic development (about 6 months after fertilisation) the Mn concentration of the egg started to increase and had at the time of hatching reached concentrations of 120 µg Mn g(-1) dry wt. egg. The egg shell was at this stage highly permeable and Mn was taken up by the embryo and egg shell in equal amounts.

Journal Article↗
PubMed1978

Survey for aflatoxin B1 in chicken eggs.

Samples of egg products were obtained during January and July 1977 from 35 establishments located in the southern part of the United States. Of the 112 samples analyzed, aflatoxin B1 was found in 1 sample of liquid egg white at a level of 0.06 ng/g. No aflatoxin was found in 101 samples of shell eggs offered for sale to consumers in Alabama, Georgia, South Carolina, and North Carolina in the late fall of 1977.

Aflatoxins↗
PubMed2004

Prevalence of high-risk egg-preparation practices in restaurants that prepare breakfast egg entrées: an EHS-Net study.

Salmonella enterica serotype Enteritidis (SE) is a common cause of foodborne illness in the United States. Foods prepared with raw shell eggs have often been associated with SE outbreaks. The federal government published the Egg Safety Action Plan in December 1999 that called for reduction of egg-preparation practices that may contribute to the survival and proliferation of SE. In seven states, an interview and brief site evaluation of 153 restaurants that prepare eggs during all hours of operation was conducted by the Environmental Health Specialists Network to determine the prevalence of such practices. Fifty-four percent (83 of 153) of restaurants pooled raw shell eggs not intended for immediate service. These pooled eggs were held a median of 4 h for scrambled eggs, 5.5 h for omelets, and 6 h for pancakes and French toast. Nearly 26% (39 of 152) of restaurants reported storing eggs at room temperature, and 5% (7 of 152) stored eggs on ice or in cold-water baths before cooking. Generally, eggs were cooked to 72 to 83 degrees C, which is above the recommended final cook temperature of 63 to 68 degrees C. Employees reported sanitizing utensils used to prepare eggs less than once every 4 h in 42% (57 of 136) of restaurants. Several areas were identified in which further emphasis might reduce egg-associated SE infections in accordance with Healthy People 2010 goals.

Consumer Product Safety↗
PubMed1978

Copper deficiency in the laying hen.

Copper deficiency in the laying hen resulted in anemia and the production of eggs which were abnormal in size and shape. Many of the eggs had shells which were wrinkled and rough in texture. There was also an increase in the number of shell-less eggs. Examination of malformed egg shells using the scanning electron microscope revealed ultrastructural changes in the mammillary layer of the shell. The effect of copper deficiency on shell formation was attributed to the shell membranes which were altered in color, appearance, and physical consistency. Amino acid analysis of the membranes indicated that the membranes from copper deficient hens were characterized by an increase in lysine content. This suggests that copper is necessary for the formation of lysine derived cross-links in a manner similar to that which occurs in connective tissue. The exact nature of these cross-links is unknown at this time.

Amino Acids↗
PubMed1976

Composition of crop and gizzard contents in the laying hen.

Crop and gizzard contents were analysed at six stages of egg formation. 2. The crop was empty during the day and full during the night while the gizzard contained a constant amount of dry matter. The water content of the crop did not change but that of the gizzard was at a minimum just after the ovulation and at a maximum 18 h later. 3. The osmotic pressure of the gizzard contents remained constant and close to that of the blood; that of the crop contents was almost isotonic at oviposition but hypertonic 18 h later. In both organs the pH of the liquid phase varied cyclicly with the egg formation and was lowest during egg shell deposition. 4. The Na+, K+ and Cl- contents of the crop liquid phase did not vary but Ca2+ increased with decreasing pH.Na+ and K+ were also constant in the gizzard liquid phase but Cl- and Ca2+ increased during shell formation. 5. It is concluded that the amount of HCl secreted by the proventiculus is related to egg shell deposition and that calcium solubilisation depends on microbial fermentation in crop and HCl secretion by proventriculus.

Animals↗
PubMed1991

Colonization of Ascaris lumbricoides eggs by the fungus Verticillium chlamydosporium Goddard.

The process of colonization of Ascaris lumbricoides eggs by the fungus Verticillium chlamydosporium was studied by scanning electron microscopy. The preparations were made by fractionation of egg suspension exposed to the fungus for four days and frozen in liquid nitrogen according to Stĕrba and Milácek (1986). Ovicidal fungus forms an abundant ramifying mycelial network in the area between the eggs. However, egg-shells are penetrated only by some hyphae without any penetration organs produced (simple hyphal penetration). In a liquid medium, after penetration, hyphae inside the eggs rapidly grow among inner structures of egg-shells and on the surface of developing larvae. In the next phase, hyphae colonize the developing larva. The eggs attacked by this fungus remain morphologically unchanged for a long time except the sites of penetration. Verticillium chlamydosporium is a fungus with unique ovicidal properties. It colonizes the eggs of Ascaris lumbricoides at all stages of embryo development and also attacks larvae inside the eggs.

Animals↗
PubMed1998

Launch conditions might affect the formation of blood vessels in the quail chorioallantoic membrane.

As a part of the first joint USA-Russian MIR/Shuttle program, fertilized quail eggs were flown on the MIR 18 mission. Post-flight examination indicated impaired survival of both the embryos in space and also of control embryo exposed to vibrational and g-forces simulating the condition experienced during the launch of Progress 227. We hypothesized that excess mechanical forces and/or other conditions during the launch might cause abnormal development or the blood supply in the chorioallantoic membrane (CAM) leading to the impaired survival of the embryos. The CAM, a highly vascularized extraembryonic organ, provides for the oxygen exchange across the egg shell and is thus pivotal for proper embryonic development. To test our hypothesis, we compared angiogenesis in CAMs of eggs which were either exposed to the vibration and g-force profile simulating the conditions at launch of Progress 227 (synchronous controls), or kept under routine conditions in a laboratory incubator (laboratory controls). At various time points during incubation, the eggs were fixed in paraformaldehyde for subsequent dissection. At the time of dissection, the CAM was carefully lifted from the egg shell and examined as whole mounts by bright-field and fluorescent microscopy. The development of the vasculature (angiogenesis) was assessed from the density of blood vessels per viewing field and evaluated by computer aided image analysis. We observed a significant decrease in blood-vessel density in the synchronous controls versus "normal" laboratory controls beginning from day 10 of incubation. The decrease in vascular density was restricted to the smallest vessels only, suggesting that conditions during the launch and/or during the subsequent incubation of the eggs may affect the normal progress of angiogenesis in the CAM. Abnormal angiogensis in the CAM might contribute to the impaired survival of the embryos observed in synchronous controls as well as in space.

Allantois↗
PubMed2004

Observations on Salmonella contamination of eggs from infected commercial laying flocks where vaccination for Salmonella enterica serovar Enteritidis had been used.

Eggs were collected monthly from 12 cage-layer flocks on four farms where Salmonella Enteritidis was present in vaccinated flocks despite vaccination with an S. Enteritidis bacterin. Where possible, hens were also taken for culture at the end of the laying period, and faecal and environmental samples were taken from the laying houses before and after cleaning and disinfection. Twenty-four batches of six egg shells from the 13 652 tested (0.18% [0.11 to 0.26 CI(95)] single egg equivalent) were positive for S. Enteritidis and 54 (0.40% [0.30 to 0.52 CI(95)] single egg equivalent) for other serovars. Six batches of 13 640 (0.04% [0.02 to 0.10 CI95] single egg equivalent) egg contents, bulked in six egg pools, contained S. Enteritidis and three batches contained other serovars. In addition three further batches contained S. Enteritidis in both contents and shells, and two other batches contained other serovars in both. The total level of contamination by S. Enteritidis of both contents and shells found in vaccinated flocks was therefore 33 batches/13 682 eggs(0.24% [0.17 to 0.34 CI(95)] single egg equivalent). The total of contamination for any Salmonella serovar was 92 batches/13 682 eggs (0.68% [0.55 to 0.84 CI(95)] single egg equivalent). These results contrast with the findings of testing of eggs from three unvaccinated flocks prior to this study where 21 batches of egg shells from a total of 2101 eggs (1.0% [0.63 to 1.56 CI(95)] single egg equivalent) and six batches of contents from 2051 eggs (0.29% [0.11 to 0.64 CI95] single egg equivalent) were contaminated with S. Enteritidis. S. Enteritidis was found in 67/699 (9.6%) of vaccinated spent hens and 64/562 (11.4%) of bulked fresh faecal samples taken from laying houses. Failure to adequately clean and disinfect laying houses and to control mice appeared to be a common feature on the farms.

Animal Husbandry↗
PubMed2003

Ontogenetic changes of the water status in the heated quail's egg as studied by nuclear magnetic resonance imaging.

The 1H-magnetic resonance imaging technique was applied for monitoring the extent of the heat coagulation in the shell egg. It is demonstrated that spin-spin relaxation time (T2) is an effective marker to observe the extent of coagulation in egg white and yolk and that the T2 value image is quite useful to recognize non-destructively the extent and status of coagulation of the heated eggs. This technique can also be applied to the material science as well as food science for observation of the inner status of the objects.

Animals↗