Search

The purpose of the present study was to evaluate the relationship between the feeding frequency and timetable on egg parameters and reproductive performance of broiler breeder hens. The study involved 480 Ross-308 strain broiler breeder hens from 31 to 38 weeks of age. Birds were randomly assigned to 15 dietary treatments, including four replicates (seven hens and one rooster/treatment), and fed conventional diet (11.7 MJ kg-1 of metabolisable energy, 14% crude protein). Treatments were as follows: (1) once-a-day feeding schedule (control), in which birds received their total allocated feed at 0400 h; (2) twice-a-day feeding schedule, in which the daily feed allowance was divided into two equal meals (50:50) and fed at 0400 and 1600 h; (3) twice-a-day feeding, 75:25 at 0400 and 1600 h; (4) twice-a-day feeding, 50:50 at 0400 and 1200 h; (5) twice-a-day feeding, 75:25 at 0400 and 1200 h; (6) twice-a-day feeding, 75:25 at 0600 and 1600 h; (7) twice-a-day feeding, 50:50 at 0600 and 1600 h; (8) three times feeding schedule, 50:25:25 at 0400, 1200 and 1600 h; (9) three times feeding schedule, 33:33:33 at 0400, 1200 and 1600 h; (10) three times feeding schedule, 25:50:25 at 0400, 1200 and 1600 h; (11) three times feeding schedule, 25:25:50 at 0400, 1200 and 1600 h; (12) three times feeding schedule, 50:25:25 at 0600, 1200 and 1600 h; (13) three times feeding schedule, 33:33:33 at 0600, 1200 and 1600 h; (14) four times feeding schedule, 33:22:22:22 at 0400, 0800, 1200 and 1600 h; and (15) four times feeding schedule, 50:17:17:17 at 0400, 0800, 1200 and 1600 h, respectively. According to our results, until 38 weeks of age the egg production, egg-shell weight, albumen height and yolk colour as well as Haugh unit were positively influenced (P < 0.05) in the hens fed twice a day. Similarly, also using the evaluation index and sub-ordinate function methods, the higher scores were obtained by birds fed more than once a day. In contrast, all feeding regimens did not affect the other egg parameters. Therefore, it can be concluded that feeding broiler breeder hens twice or three times per day improved the egg traits and reproductive performance during the egg peak production phase. [ABSTRACT FROM AUTHOR]

This study was conducted to assess the effects of flaxseed oil and dried whitebait as a source of ω-3 fatty acids (ω-3 FA), which could be used to produce eggs enriched with ω-3 FA, and of fructo-oligosaccharide (FOS) as a source of prebiotics on performance of hens (commercial Hy-Line Brown laying hens), and FA composition, internal quality, and sensory characteristics of the eggs. Dietary FOS increased egg weight. The amounts of a-linolenic (ALA), eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) in the eggs from the hens fed the flaxseed oil alone or flaxseed oil+dried whitebait diets were higher than those of the control. Hedonic scores for off-flavor, fishy flavor, buttery taste and overall acceptability of the eggs from the hens fed the diet containing flaxseed oil+ dried whitebait were lower (p<0.05) than those of the control. Overall acceptability of the eggs from the hens fed the diet containing soybean oil+dried whitebait was lower (p<0.05) than that of the control. However, all the sensory attributes of the eggs from the hens fed the diet containing flaxseed oil, dried whitebait and FOS were not significantly different from those of the control. These results confirmed that flaxseed oil increases the ALA content in the eggs and a combination of flaxseed oil and dried whitebait increases EPA and DHA in the eggs. Of significance was that addition of FOS to the flaxseed oil+dried whitebait diet improves the sensory characteristics of the eggs enriched with ω-3 FA. [ABSTRACT FROM AUTHOR]

Abstract: Effects of dietary flaxseed meal (FSM) on production performance, egg quality, hatchability, and fatty acids profiles in egg yolks of geese and thigh meat from their offspring were studied in a 35-d study. A total of 288 female Huoyan geese (28-wk-old) were divided into 4 experimental diets containing FSM at 0 (control), 50, 100, and 150g/kg. There were 9 replicate pens per treatment with 8 geese per replicate pen. The total number of eggs produced (linear, P=0.04) and feed efficiency were greater (linear, P=0.04) in FSM containing groups than control diet. The inclusion of FSM in the geese diet linearly decreased the concentration of palmitic acid (linear, P=0.02) and saturated fatty acid (linear, P=0.05) in egg yolk, whereas the contents of C18:3n-3 (linear, P=0.04), C22:6n-3 (quadratic, P=0.05), total polyunsaturated fatty acids (PUFA; linear, P=0.01), and total n-3 PUFA (linear, P=0.01) were enhanced as the FSM levels increased. The arachidonic acid concentration (P=0.05) and n-6/n-3 ratio (P<0.05) also linearly decreased as the FSM inclusion level increased. At the end of the 35-d breeder experiment, all hatching eggs laid in 6 consecutive days in each group were collected and incubated. In 1-d-old goslings, the inclusion of FSM linearly decreased C16:0 (P=0.03) and total saturated fatty acid (P=0.04) concentrations in thigh meat. The contents of C18:3n-3 increased (linear, P=0.01), whereas C20:4n-6 decreased (linear, P=0.01) in FSM supplemented groups compared to control group. The concentrations of PUFA and total n-3 PUFA were linearly increased (P=0.04 and 0.01, respectively) and the n-6/n-3 ratio decreased linearly (P=0.02) as the FSM levels increased. In conclusion, dietary addition of FSM up to 150g/kg levels improved the egg production without any effect on egg quality and breeding performance. Moreover, feeding FSM to geese can increase the n-3 fatty acids concentration in egg yolk and deposition in the offspring in a dose-dependent manner. [Copyright &y& Elsevier]

Highlights: [•] Laying hens received feed containing 0.27±0.034mg/kg of semduramicin. [•] The plateau level in eggs was reached (16.1±5.19μg/kg). [•] The residues of semduramicin in eggs exceeded significantly maximum levels (2μg/kg). [ABSTRACT FROM AUTHOR]

Ovalbumin, ovotransferrin, ovomucin, and lysozyme are a few of the egg white proteins that can be used as functional components. The objective of this study was to develop a simple, sequential separation method for multiple proteins from egg white. Separated proteins are targeted for human use, and thus any toxic compounds were excluded. The methods for individual components and the sequential separation were practiced in laboratory scale first, and then tested for scale-up. Lysozyme was separated first using FPC3500 cation exchange resin and then ovomucin using isoelectric precipitation. Ovalbumin and ovotransferrin were separated from the lysozyme- and ovomucin-free egg white by precipitating ovotransferrin first using 5.0% (wt/ vol) (NH4)2S04 and 2.5% (wt/vol) citric acid combination. After centrifugation, the supernatant (SI) was used for ovalbumin separation and the precipitant was dissolved in water, and reprecipitated using 2.0% ammonium sulfate (wt/vol) and 1.5% citric acid (wt/vol) combination. The precipitant was used as ovotransferrin fraction, and the supernatant (S2) was pooled with the first supernatant (SI), desalted using ultrafiltration, and then heat-treated to remove impurities. The yield of ovomucin and ovalbumen was >98% and that of ovotransferrin and lysozyme was >82% for both laboratory and scale-up preparations. The SDS-PAGE and western blotting of the separated proteins, except for ovomucin, showed >90% purity. The ELISA results indicated that the activities of separated ovalbumin, ovotransferrin, and lysozyme were >96%. The protocol separated 4 major proteins in sequence, and the method was simple and easily scaled up. [ABSTRACT FROM AUTHOR]

Egg components are important mediators of prenatal maternal effects in birds and other oviparous species. Because different egg components can have opposite effects on offspring phenotype, selection is expected to favour their mutual adjustment, resulting in a significant covariation between egg components within and/or among clutches. Here we tested for such correlations between maternally derived yolk immunoglobulins and yolk androgens in great tit ( Parus major) eggs using a multivariate mixed-model approach. We found no association between yolk immunoglobulins and yolk androgens within clutches, indicating that within clutches the two egg components are deposited independently. Across clutches, however, there was a significant negative relationship between yolk immunoglobulins and yolk androgens, suggesting that selection has co-adjusted their deposition. Furthermore, an experimental manipulation of ectoparasite load affected patterns of covariance among egg components. Yolk immunoglobulins are known to play an important role in nestling immune defence shortly after hatching, whereas yolk androgens, although having growth-enhancing effects under many environmental conditions, can be immunosuppressive. We therefore speculate that variation in the risk of parasitism may play an important role in shaping optimal egg composition and may lead to the observed pattern of yolk immunoglobulin and yolk androgen deposition across clutches. More generally, our case study exemplifies how multivariate mixed-model methodology presents a flexible tool to not only quantify, but also test patterns of (co)variation across different organisational levels and environments, allowing for powerful hypothesis testing in ecophysiology. [ABSTRACT FROM AUTHOR]

The research focused on the influence exerted by the storage conditions of table eggs on their physical quality traits. Four groups of eggs were set up (150 eggs/group), submitted to storage throughout 40 days, under different microclimate parameters (Lc=4°C and 90% relative moisture- RM; L-1=10°C and 80% RM; L-2 =15°C and 70% RM; L-3=25-30°C and 45% RM). At the end of the storage period, the lowest proportions of physical parameters depreciations were observed after refrigeration (Lc group) (1.11% for the weight; 1.17% for the specific gravity; 4.61% for the albumen index; 7.88% for the yolk index and 3.95% for the Haugh index. In the other groups, which simulated the storage conditions used by eggs marketers, freshness lost was directly proportional with the provided parameters values; thus, after 40 days of storage, the physical traits presented lower values, compared to the fresh eggs: 1.91-4.49% for the weight, 1.98-4.45% for the specific gravity, 14.13-49.91% for the albumen index, 19.86-50.9% lower for the yolk index and 12.84-26.59% for the Haugh index. The achieved results certify that the storage of table eggs must be carried under refrigeration conditions, at +4°C and 90% relative moisture. [ABSTRACT FROM AUTHOR]

Egg white contains many functionally important proteins. Ovalbumin (54%), ovotransferrin (12%), ovomucoid (11%), ovomucin (3.5%), and lyso-zyme (3.5%) are among the major proteins that have high potentials for industrial applications if separated. The separation methods for these proteins from egg white have been developed since early 1900, but prepa-ration methods of these proteins for commercial ap-plications are still under development. Simplicity and scalability of the methods, use of nontoxic chemicals for the separation, and sequential separation for mul-tiple proteins are very important criteria for the com-mercial production and application of these proteins. The separated proteins can be used in food and pharmaceutical industry as is or after modifications with enzymes. Ovotransferrin is used as a metal transporter, antimicrobial, or anticancer agent, whereas lysozyme is mainly used as a food preservative. Ovalbumin is widely used as a nutrient supplement and ovomucin as a tumor suppression agent. Ovomucoid is the major egg allergen but can inhibit the growth of tumors, and thus can be used as an anticancer agent. Hydrolyzed pep-tides from these proteins showed very good angiotensin I converting enzyme inhibitory, anticancer, metal bind-ing, and antioxidant activities. Therefore, separation of egg white proteins and the productions of bioactive peptides from egg white proteins are emerging areas with many new applications. [ABSTRACT FROM AUTHOR]

The impact of egg color, hen strain, and molting on the nutritional composition of eggs is lim-ited. Therefore, this study compared nutritional com-position and component percentages of cage-produced shell eggs with respect to egg color, hen strain, and molt. Four strains were selected from the North Caro-lina Layer Performance and Management Test: Hy-Line Brown (HB) and Bovans Brown (BB), and Hy-Line W-36 (HW) and Bovans White (BovW) were select-ed. Two groups from each strain were selected and 2 groups of molted HW and BovW were selected and compared with their nonmolted counterparts to ex-amine the molt's impact. Two sets of eggs from each replicate were collected simultaneously at 101 wk of age. One sample of eggs was broken into a 12-egg pool stomached for 3 min (n = 12 samples), then divided into six 50-mL tubes, sealed, and frozen to be sent for cholesterol, n-3 fatty acids, saturated fat, monounsatu-rated fats, polyunsaturated fats, ß-carotene, vitamin A, and vitamin E analyses. The other set of 12 eggs was then assessed for component percentages. The HW eggs had a greater (P < 0.05) percentage of yolk than the BovW eggs of 28.12 versus 27.00%, respectively; however, the BovW eggs had 1.0% more albumen. The HB and BB egg components were not different. Brown eggs were heavier (P < 0.01) than white eggs. White eggs had greater (P < 0.0001) percent yolk and the brown eggs had greater (P < 0.0001) percent albumen. The eggs from molted hens had a greater (P < 0.001) percent shell. Total fat content in the samples was (P < 0.05) higher in white eggs by 0.70% than brown eggs due to increased saturated and polyunsaturated fats. The molting of hens reduced (P < 0.01) saturated fats by 0.21% in the egg. Vitamin A levels were higher (P < 0.0001) in white eggs, and vitamin E was higher (P < 0.0001) in brown eggs. Strain and molt appear to influ-ence nutrient composition and component percentages in eggs produced from laying hens. [ABSTRACT FROM AUTHOR]

The nest is a key element of avian reproductive fitness. It provides the developmental environment for the embryo and nestling thereby affecting their quality and survival. Nests are often constructed by the male and nest quality, elaboration, and ornamentation vary among males in a species. Therefore, male nest-building behaviour is likely under sexual selection and females may use male nest-building behaviour and nest features as cues in mate choice and their own reproductive investment. We tested this hypothesis in European starlings (Sturnus vulgaris). Male starlings present green plants to females during their courtship display and furbish their nests with variable quantities of fresh green plants. The highest frequency of plant incorporation into the nest occurs during pair formation and oogenesis. We determined nest composition and measured yolk testosterone concentrations in eggs. Yolk testosterone concentrations were positively correlated with the amount of green plant material in nests. Because males use green nest material in courtship and green nest material positively affects nestlings' development, we suggest that female European starlings use male nest-building effort, ritualised courtship display of green plants, and nest characteristics in mate choice, and adjust yolk testosterone levels in the eggs to the quality of the nest to optimise offspring growth. [ABSTRACT FROM AUTHOR]

Relationships between physiological variables of middle and late post-hatch broilers with their corresponding egg and embryo variables were examined. Sixty Ross×Ross 708 broiler hatching eggs were randomly set on each of 8 replicate tray levels of an incubator. On 10.5 d of incubation, transponders were implanted in the air cells of 4 embryonated eggs per replicate for determination of internal egg temperature (Temb) through d 18.5. On d 18.5, the implanted embryonated eggs were transferred to a hatcher unit where they were monitored for hatch every 12 h. Incubation length, eggshell water vapor conductance (GH2O), specific GH2O (gH2O; GH2O adjusted to a 100 g set egg weight basis), and GH2O constants (KH2O) of the embryonated eggs were determined. Chicks were placed in corresponding replicate floor pens and were grown out from 0 (21.5 d of incubation) to 48 d of age. On 28 and 48 d post-hatch, approximately 2 birds per pen were necropsied for determination of BW, and the relative weights and moisture concentrations of their liver, breast muscle, and left gastrocnemius muscle. Breast muscle moisture concentration on d 28 was negatively correlated with GH2O, gH2O, and KH2O, and breast muscle moisture concentration on d 48 was negatively correlated with incubation length. However, relative body and breast muscle weights on d 48 were positively correlated with gH2O and KH2O, and relative BW on d 48 was positively correlated with incubation length. More importantly, relative breast muscle weight on d 48 post-hatch was negatively correlated with Temb. The variables Temb, GH2O, gH2O, and KH2O may differentially influence the physiological variables in birds during the middle and late post-hatch grow out periods, and bird metabolic and hydration statuses may be adjusted later during the post-hatch period, so that bird BW will eventually reach its genetically predetermined level. [ABSTRACT FROM AUTHOR]

This research investigated the potential of multi-pass homogenization treatment for the inactivation of Salmonella enterica serovar Enteritidis inoculated at different levels in liquid whole egg (LWE) comparing the efficacy of this treatment with a traditional thermal one performed at 65 °C. Moreover, the effects of high pressure treatment (HPH) on structural and functional properties such as viscosity, microstructure and foaming abilities of LWE were investigated. The data obtained suggested that the multi-pass high pressure treatment at 100 MPa of S. enterica serovar Enteritidis inoculated in LWE at 7 and 4 log CFU/ml resulted in a first order inactivation kinetic, while the thermal inactivation curves of S. enterica serovar Enteritidis inoculated at 8 and 4 log CFU/ml presented a non-linear behaviour, with a marked tail after 3 min of treatment at 65 °C. Additionally, HPH treatment caused an increase in foaming capacity of LWE, with respect to the untreated samples, passing from values of 26% of the control to 50% of pressure treated samples. [ABSTRACT FROM AUTHOR]

As female birds are able to lay no more than a single egg each day, in those species producing larger clutches the first laid eggs may get a developmental head-start over later eggs in the clutch. All other things being equal, the differential pattern of development across the clutch may contribute to hatching asynchrony and subsequent inequity in the competition between brood mates, and ultimately increase variance in the quality and fitness of first- and last-laid offspring. It has been suggested that females might allocate resources differently across the laying sequence to moderate the developmental rate and hatching time of different embryos. We tested this theory in the Zebra Finch Taeniopygia guttata, a common model species for investigating maternal effects in birds. We removed 758 eggs from 160 nests shortly after they were laid and used artificial incubators to control for parental effects and monitor hatching times. Eggs from larger clutches consistently hatched sooner than those from average-sized clutches, demonstrating that the intrinsic properties of an egg can alter the developmental time of embryos. There were also differences in the development time of eggs across the laying sequence, but these patterns were weaker, inconsistent and unrelated to sequential investment across the laying sequence in a straightforward way. This study indicates that maternal resource allocation to eggs across the laying sequence and across clutch sizes can influence development times and play a potentially important role in determining the competitive dynamics of broods. [ABSTRACT FROM AUTHOR]

Background Diagnostic and accidental food allergic reactions may be modified by the matrix containing the allergenic food. Previous studies of double-blind, placebo-controlled food challenges ( DBPCFCs) with peanut found an effect of the fat content of the challenge matrix on the severity of the challenge reactions. Objective The aim of this study was to examine whether the fat content of the food matrix is related to eliciting dose and reaction severity in DBPCFCs with heated hen's egg. Methods Sensitized egg allergic children ( n = 59) undergoing DBPCFCs with egg as a routine diagnostic procedure in our tertiary care centre were evaluated retrospectively. Three different recipes were used for the food matrix: vanilla pudding, pancake and minced meat, containing 22.8%, 31.9% and 52.7% fat (weighted average), respectively. The eliciting dose (i.e. the highest cumulative dose to which the child reacted) was analyzed by Kaplan-Meier log-rank statistic and by Cox regression. Reaction severity was quantified by using an index (range 1-12) and was analysed by multiple linear regression analysis. Results The overall influence of type of recipe on eliciting dose was not significant ( P = 0.12). The rate of response to minced meat (with the highest fat content) was not significantly different from pudding [ HR = 0.61 (0.26-1.45, P = 0.26) or pancake ( HR = 1.41 (0.50-3.99), P = 0.52] after adjustment for confounders. The type of recipe did not influence the severity of the challenge reaction. The severity of the challenge reaction for minced meat compared to pudding and pancake was 1.06 (0.52-2.16), P = 0.87 and 0.81 (0.32-2.01), P = 0.64, respectively, after correction for confounders. Conclusion and Clinical Relevance In contrast to similar research with peanut, no significant influence of the fat content of the matrix was found on the eliciting dose or severity of the reaction in 59 DBPCFCs with hen's egg. Matrix fat content differences comparable to those reported here may not be an important co-determinant of reaction severity for all allergenic foods. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study was to evaluate the effect of extruded amaranth grains (AMG) in laying hen diets on performance, egg traits, egg yolk fatty acids composition, as well as selected blood characteristics. A total of 60 Lohmann Brown laying hens, 24wk of age, were randomly distributed into 3 dietary treatments and fed for 10wk. The AMG was used at the levels of 0%, 5%, and 10% in the diets of the control and 2 treatment groups, respectively. Each dietary treatment was divided into 4 replicates, comprising of 5 hens each. Hens were housed in a 3-tier battery system. Feed and water were provided ad libitum. Blood samples and eggs were collected after 5wk and at the end of the experiment. Amaranth grain supplementation increased body weight (1.64, 1.66, and 1.72kg for diets containing 0%, 5%, and 10% AMG, respectively; linear, P<0.01). Although hens responded to AMG supplementation linear and quadratically (P<0.01), the greatest egg production and the lowest feed conversion ratio were observed with 5% AMG. No differences in the mean egg weight, eggshell weight, yolk and albumen weight, thick albumen height, Haugh units and breaking strength of eggshells were observed in hens fed AMG-supplemented diets. Also, sensory analysis of eggs did not reveal any differences among hens fed different diets. Fatty acids content of egg yolk was similar in all treatments, although in hens fed 5% AMG, the polyunsaturated fatty acid (n-6), especially linoleic acid, level was slightly greater and the n-6/n-3 acid ratio was decreased. The concentrations of alanine aminotransferase, aspartate aminotransferase, and glucose level were reduced linearly after 5wk (P=0.01–0.03) by increasing AMG supplementation. The quadratic effect on alanine aminotransferase at wk 5 (P=0.02) and 10 (P<0.01) was also observed. The results showed that dietary inclusion of AMG at the level of 5% increased hen performance and did not negatively influence the hens' health conditions and also quality and sensory traits of eggs. [Copyright &y& Elsevier]

Abstract: In oviparous species, proteins and lipids found in the vitellus form the lipoproteins called lipovitellins that are the major source of energy for the development, growth, and survival of the embryo. The energy resources provided by the lipovitellins have not yet been investigated in the Order Araneae. Using the wolf spider Schizocosa malitiosa (Lycosidae) as an experimental model, we identified and characterized the lipovitellins present in the cytosol, focusing on the energetic contribution of those lipoprotein particles in the vitellus. Two lipovitellins (LV) named SmLV1 and SmLV2 were isolated. SmLV1 is a high-density lipoprotein with 67% lipid and 3.6% carbohydrate, and SmLV2 is a very high-density lipoprotein with 9% lipid and 8.8% carbohydrate. Through electrophoresis in native conditions we observed that SmLV1 has a molecular mass of 559kDa composed of three apolipoproteins of 116, 87, and 42kDa, respectively. SmLV2 comprised several proteins composed of different proportions of the same subunits (135, 126, 109, and 70kDa). The principal lipids of these lipovitellins are sphingomyelin+lysophosphatidylcholine, esterified sterols, and phosphatidylcholine. Lipovitellin-free cytosol contains abundant phospatidylcholine and triacylglyceride related to the yolk nuclei (the vitellus organizing center). The principal fatty acids of SmLV1 and SmLV2 are 18:2 n−6, 18:1 n−9, and 16:0. Spectrophotometry detected no pigments in either the lipovitellins or the cytosol. The egg caloric content was 92cal/g, at proportions of 59.8% protein, 20.1% carbohydrate, and 19.9% lipid. SmLV1 and SmLV2 provided 19.5% and 17.1% of the calories, respectively. Both lipovitellins contribute mainly with proteins (15.8–18%), with the input of carbohydrates and lipids being lower than 1.3%. [Copyright &y& Elsevier]

Vitamin D deficiency is a global health problem. This study aimed to investigate the efficacy of ultraviolet (UV) B radiation for improving vitamin D3 content of eggs and meat. In a two-factorial design hens that received diets with 0 (-D3) or 3,000 IU (+D3) vitamin D3/kg were non-exposed (-UVB) or exposed to UVB radiation (+UVB) for 3 h daily over 4 weeks. Data show that UVB radiation was very effective in raising the vitamin D3 content of egg yolk and meat. Egg yolk from +UVB/−D3 hens had a higher vitamin D3 content (17.5±7.2 µg/100 g dry matter (DM)) than those from the –UVB/+D3 group (5.2±2.4 µg/100 g DM, p<0.01). Vitamin D3 content in egg yolk of vitamin D3-supplemented hens could be further increased by UVB radiation (32.4±10.9 µg/100 g DM). The content of 25-hydroxyvitamin D3 (25(OH)D3) in the egg yolk also increased in response to UVB, although less pronounced than vitamin D3. Meat revealed about 4-fold higher vitamin D3 contents in response to UVB than to dietary vitamin D3 (p<0.001). In conclusion, exposure of hens to UVB is an efficient approach to provide consumers with vitamin D3-enriched foods from animal sources. [ABSTRACT FROM AUTHOR]

The research was performed on 108 laying hens, Isa-Brown hybrid, divided in four groups, 27 heads/group. Prebiotic Actigen was supplemented in total mixed ratio (TMR) in group 1E using a proportion of 0.06%, prebiotic Bio-Mos in proportion of 0.1% (group 2E) and organic Se (Sel-Plex) in proportion of 0.04% (group 3E). The trial developed within 6 weeks, first laying stage (33 weeks-39 weeks of age), respectively. During trial, the following issues were studied: average weight of egg structure, egg proportion, chemical composition of egg and egg quality (egg size index, egg volume, index white, index yolk, Haugh units, specific subject of egg weight). The use of prebiotics (Bio-Mos and Actigen) and organic selenium (Sel-Plex) in the mentioned doses determined increase in the average weight of egg structure (egg white, yolk and shell), and also an increased eggshell thickness and an increase in the protein content in egg white and yolk. Also is observed an increase in Ca content in eggshell and an increase in Se in egg (egg white+yolk). The results obtained confirm the favourable influence of prebiotics and organic selenium on the egg quality of laying hens in the first laying stage. [ABSTRACT FROM AUTHOR]

Understanding the reproductive biology of commercially important species is important to ensure the continued health and sustainability of marine ecosystems. North Carolina's blue crab fishery is the fifth largest crab fishery in the United States, and the current stock status is "of concern" due to recent low harvest totals. Thus, knowledge of factors contributing to future recruitment in this fishery is clearly needed. There are few data on the variation and consequences of blue crab female size on egg quality; this study aimed to evaluate whether female size has any bearing on egg quality or larval size. Eggs of 110 ovigerous females were sampled in June through July of 2010 and 2011, and the eggs' energy content, lipid content, and fatty acid profiles were measured. Eighteen ovigerous females were maintained until hatch, at which point zoea sizes were measured. Female size did not strongly correlate with any measurement of egg quality or zoea size. Energy content and fatty acid profiles significantly differed between 2010 and 2011. Eggs extruded later in the season had higher dry weight energy content in 201 l, while overall zoea size declined in later hatch dates. Our results indicate that lipid content in blue crab eggs does not drive overall energy content, and female size does not correlate with our measures of reproductive success. Instead, we propose that environmental or genetic factors are responsible for this variation. Management plans for protecting blue crab broodstock should reflect annual variation present in egg quality rather than emphasizing the influence of female size on egg quality. [ABSTRACT FROM AUTHOR]

Highlights: [•] No sex related differences for yolk T, E2, A4, P4 and DHT in unincubated chicken eggs. [•] No sex related differences for egg weight, length and width in chicken eggs. [•] Yolk E2 significantly predicted by interaction of sex of egg and hen body weight. [•] Concentrations of yolk A4 significantly associated with hen body weight. [•] Associations found among various egg parameters i.e. egg hormones and dimensions. [ABSTRACT FROM AUTHOR]

The aim of this study was the comparative analysis of the chemical composition determined for 30 samples of eggs (white, yolk, mixture) from hens of Lohmann Brown Classic breed in their first production cycle. Research has been organized in two units in Romania with different systems of hen egg production (conventional and organic). Determination of gross chemical composition using specific methods in order to standards and regulations in force. Statistical analysis, revealed significant differences between the mean values calculated for white, yolk, mixture samples derived from conventional system compared with the ecological one for crude protein content, SEN, calcium, magnesium, sodium and zinc only in egg white samples and egg mixture; significant for dry matter in samples of egg white, zinc in yolk samples and phosphorous in egg mixture samples. Significant differences were recorded for crude ash content to white, yolk, mixture and crude fat content and phosphorous in samples of albumen. [ABSTRACT FROM AUTHOR]

Conspicuous blue-green egg colouration has been of interest to scientists and naturalists for more than a hundred years; however, the function of this trait has never been fully understood and has spurred extensive debate. The American thrashers exhibit great variation in egg colouration and patterning, and also show variation in male brood patch development. A recent hypothesis suggests that conspicuous egg colouration has evolved as the product of sexual conflict, where females may create conspicuous eggs to obtain greater amounts of male care, either in the form of male incubation or incubation assistance to prevent their eggs from being vulnerable to visually orienting predators and brood parasites. The American thrashers, a genus comprising of 10 species, exhibits striking variation in egg colouration and patterning, and also show variation in male brood patch development. By using avian visual modelling, I show that blue-green chroma of American thrasher eggs is positively related to their degree of conspicuousness against a nest background, while brown chroma is negatively related. Interestingly, the degree of male brood patch vascularisation is directly related to eggshell conspicuousness in American thrashers. I suggest that in the American thrashers, male brood patch vascularisation has evolved in response to conspicuous eggshell colouration to mitigate visual risks. Here I show that the degree of male brood patch vascularisation is directly related to relative paternal incubation effort in more than 300 North American breeding birds. This suggests that American thrasher species that possess both conspicuous eggs and brood patches, have most likely evolved to keep these conspicuous nest contents concealed, thereby reducing risk of visual detection. I suggest that these patterns are not unique to thrashers, but may extend to several avian families. [ABSTRACT FROM AUTHOR]

A fertilized chicken egg is a unit of life. During hatching, transport of nutrients, including calcium, have been reported from the egg components to the developing embryo. Calcium is mobilized from the eggshell with the involvement of Ca-binding proteins. In addition, other unknown proteins may also play some important roles during embryo developing process. Therefore identification and prediction of biological functions of eggshell membrane (ESM) proteins during chick embryo development was conducted by proteome analysis. Comparison of different lysis solutions indicated that the highest ability to extract ESM proteins could be obtained with 1 % sodium dodecyl sulfate in 5 mM Tris-HCl buffer pH 8.8 containing 0.1 % 2-mercaptoethanol. In this study fertilized Cornish chicken eggs were incubated at 37 °C in humidified incubators for up to 21 days. At selected times (days 1, 9, 15 and 21), samples were taken and the ESMs were carefully separated by hand, washed with distilled water, and air-dried at room temperature. The ESM proteins were then solubilized and analyzed by proteome analysis. Sodium dodecyl sulfate polyacrylamide gel electrophoresis combined with high performance liquid chromatography and mass spectrometry revealed 62 proteins in the ESM; only keratin is known ESM protein, 8 of which are egg white proteins and related while 53 others have not previously been reported. Some differences in the types of proteins and their molecular functions were noted in ESM at different incubation times. One protein which was present only at days 15 and 21 of egg incubation was identified as a calcium binding protein i.e. EGF like repeats and discoidin I like domain 3 (EDIL3 homologous protein). [ABSTRACT FROM AUTHOR]

In egg laying species, breeding females may adjust the allocation of nutrients or other substances into eggs in order to maximise offspring or maternal fitness. Cooperatively breeding species offer a particularly interesting context in which to study maternal allocation because helpers create predictably improved conditions during offspring development. Some recent studies on cooperative species showed that females assisted by helpers produced smaller eggs, as the additional food brought by the helpers appeared to compensate for this reduction in egg size. However, it remains unclear how common this effect might be. Also currently unknown is whether females change egg composition when assisted by helpers. This effect is predicted by current maternal allocation theory, but has not been previously investigated. We studied egg mass and contents in sociable weavers (Philetairus socius). We found that egg mass decreased with group size, while fledgling mass did not vary, suggesting that helpers may compensate for the reduced investment in eggs. We found no differences in eggs’ carotenoid contents, but females assisted by helpers produced eggs with lower hormonal content, specifically testosterone, androstenedione (A4) and corticosterone levels. Taken together, these results suggest that the environment created by helpers can influence maternal allocation and potentially offspring phenotypes. [ABSTRACT FROM AUTHOR]

A cheap, reliable and practical high-performance liquid chromatography–tandem mass spectrometric method was developed for the simultaneous determination of seven anabolic steroids in eggs, including trenbolone, boldenone, nandrolone, stanozolol, methandienone, testosterone and methyl testosterone. The analytes were extracted from the egg samples using methanol. The extracts were subjected to the removal of fat by freezing-lipid filtration and then further purified by liquid–liquid extraction using tert-butyl methyl ether. The analytes were separated on a Luna C18 column by a gradient elution program with 0.1% formic acid and acetonitrile. This method was validated over 1.00–100 ng/g for all steroids of interest. The correlation coefficients (r) for each calibration curve are higher than 0.99 within the experimental concentration range. The decision limits of the steroids in eggs ranged from 0.20 to 0.44 ng/g, and the detection capabilities were below 1.03 ng/g. The average recoveries were between 66.3 and 82.8% in eggs at three spiked levels of 1.00, 1.50 and 2.00 ng/g for each analyte. The between-day and within-day relative standard deviations were in the range of 2.4–11%. High matrix suppression effects were observed for all compounds of interest. [ABSTRACT FROM PUBLISHER]

Abstract: Nationwide sampling in the U.S. of whole large eggs, to update values in the United States Department of Agriculture (USDA) National Nutrient Database for Standard Reference (SR) (http://www.ars.usda.gov/nutrientdata), was conducted in 2000–2001 and in 2010. Retail cartons of large eggs were obtained from 12 supermarket locations using statistical sampling plans based on market share and census data. Cholesterol was analyzed at three laboratories using standard methods involving gas chromatography of the saponified total lipid extract. Vitamin D3 and 25-OH-vitamin D3 (2010 samples only) were analyzed by HPLC and UHPLC–MS/MS. Quality control materials were included to validate the accuracy and precision of measurements. The mean cholesterol content decreased 51mg/100g (12%; p <0.0001), from 423mg/100g in 2000–2001 to 372 (range 344–405) in 2010. Over the same period, average vitamin D3 increased by 60%, to 2.05μg [80IU]/100g (range 0.97–12.1). Samples from 2010 contained 0.65μg 25-OH-D3/100g (range 0.43–1.32). The disparate vitamin D (and cholesterol) content of eggs sampled from different locations may reflect industry efforts to modify poultry feed or supplements to affect the nutrient profile of eggs. Cholesterol and vitamin D3 data from this work were included in SR release 23, and support food consumption surveys, food and nutrition policy, and consumer education. [Copyright &y& Elsevier]

Abstract: Egg traceability/authenticity is a worldwide concern. Stable isotope techniques have been suggested as a tool to address this issue. To further validate the use of these techniques, a research project was undertaken to evaluate what effect sample collection and preparation have on the measured isotopic composition of egg components. The timing of egg collection, the timing of egg preparation after collection, and the use of pasteurisation were investigated. The C, N, O, and S isotopic compositions of egg components from 7 different production systems were measured. Two sets of eggs were collected (4months apart). It was found that the ‘isotopic fingerprint’ of a particular production system was maintained over time, and that it may be possible to trace liquid egg products based on isotopic data from fresh eggs. The findings from this study support the integration of stable isotope techniques in egg traceability/authenticity systems. [Copyright &y& Elsevier]

Introduction. The quality of eggs is an inclusive and necessary module for fish cultivation, and its applicability has been demonstrated in species of production interest. Objective. As an strategy to improve the production standards for red tilapia, this research work aimed to determine the existence of functional relationships between the egg's structure under dimension and composition terms, and the quality results defined in terms of survival during the first stages. Materials and methods. A follow up process was performed on the spawnings of 50 females and, for each one and her corresponding oviposition, records of 15 morphometric and dimensional variables were taken, respectively, and complemented with 11 variables more, associated to the egg's composition. The efficiency of the production process was determined departing from survival, which was registered through three efficiency rates (IEINC: incubation; IELARV: larvae culture and IETOTAL, which gathers the first two). The analysis of the data was performed based on significant correlations (α=0.05), determined between the pairs of variables and between these and the indexes. When it was pertinent, descriptive models were determined via simple and multiple linear regressions. Results. No significant relationship was established in the efficiency between the incubation and larvi-culture stages. Linear equations were obtained, thus explaining IEINC through the volume of the oviposition and the IELARV through the density of the egg, although the determination coefficients were low in the models defined. The significant linear relationships, which with a major adjustment explain the indexes, included the content of saturated fat acids in particular. Conclusions. Despite the fact the models calculated were significant, their practical usefulness is limited because the low prediction capability provided by the reduced determination coefficients defined. The total efficiency of the process depends, mainly, on the results that appear during the incubation, because there was no relationship between the survival during the incubation and larvae culture stages in the production of fingerlings of this species. [ABSTRACT FROM AUTHOR]

The objective of this study was to deter-mine the effects of feeding high concentrations of corn distillers dried grains with solubles (DDGS) on chemi-cal composition and selected nutrient content of egg yolk. Four isocaloric diets were formulated to contain 0, 17, 35, or 50% corn DDGS. A total of two hundred forty 54-wk-old Single-Comb White Leghorn laying hens were randomly allotted to 2 birds per cage with 3 consecutive cages representing an experimental unit (EU). Each EU was randomly assigned to 1 of 4 dietary treatments according to a completely randomized de-sign. Hens were fed for a 24-wk experimental period af-ter transition feeding to gradually increase corn DDGS inclusion over a 4-wk period. Two sets of experimental diets were formulated to meet or exceed the NRC nutrient recommendations for laying hens. Each diet for-mula was fed for 12 wk. Chemical composition and nu-tritional components in egg yolk were measured every 2 wk. The results showed that egg yolk from hens fed a DDGS-containing diet tended to have higher fat con-tent and lower protein content. Total polyunsaturated fatty acids were significantly increased by the DDGS diet. The contents of choline and cholesterol were ini-tially higher in the 50% DDGS treatment group, but were not different in the later period, especially dur-ing the last 4 wk. Lutein content increased linearly as DDGS level increased. The results indicated that feed-ing a high level of DDGS can increase the content of lutein and polyunsaturated fatty acids in egg yolk, but may not affect the content of cholesterol and choline. [ABSTRACT FROM AUTHOR]

Eggs (n = 1,800) obtained from Ross broiler breeders at 32 and 48 wk of age were incubated at either a constant temperature of 37.6CC throughout (Tl), or the temperature was reduced for 6 h to 36.6°C each day during embryonic age (EA) 10 to 18 (T2). Yolk sac, liver, and brain fatty acid profiles and oxidant and antioxidant status of liver and brain were measured at EA 14, 19, and day of hatch (DOH). Fatty acid pro-files of yolk sac, liver, and brain were influenced by age of breeder with significant breeder hen age x incuba-tion temperature interactions. At EA 14, higher levels of 20:4n-6 and 22:6n-3 had been transferred from the yolk sac to T2 embryos from younger than older breed-ers, whereas for Tl and T2 embryos, yolk sac 20:4n-6 and 22.6n-3 values were similar for older breeders. Ac-cumulation of 20:4n-6 and 22:6n-3 fatty acids in the liver of Tl and T2 embryos from younger breeders was similar; however, T2 embryos from older breeders had higher liver levels of 20:4n-6 and 22:6n-3 than Tl em-bryos. At EA 19, liver nitric oxide levels were higher for T2 embryos from younger breeders than those from breeders incubated at Tl. Brain catalase levels of T2 embryos from younger breeders were higher than those from older breeders at DOH. Thus, changes in fatty acid profiles and catalase and nitric oxide production of brain and liver tissues resulting from 1°C lower incu-bation temperature from EA 10 to 18 reflect adaptive changes. [ABSTRACT FROM AUTHOR]

Abstract: Sixty Cobb 500 broiler breeder hens, 22 wks of age, were individually placed in galvanized cages and fed diets without iron (Fe) supplementation for 12 weeks. Birds were then randomly allocated to six dietary treatments with the same nutrient profile, except for Fe, in a factorial of two diets (all vegetable and meat and bone meal - MBM) and three Fe sources (control, inorganic and complexed). The all-vegetable diet was formulated with maize, soybean meal and wheat bran whereas the MBM containing diet included 25g MBM/kg. The control diets were not supplemented with Fe, whereas inorganic and complexed diets had 60mg Fe/kg as supplement from Fe2+ sulfate or Fe-amino acid (Fe-AA), respectively. Diets were provided for three periods of four weeks each and eggs were collected daily. Hen day egg production and Fe content of yolk and albumen were analyzed using a two-way anova with repeated measures. Egg production was lowest (P<0.05) for birds fed diets without Fe supplementation but no difference (P>0.05) was detected between the inorganic and complexed Fe sources. Contents of Fe in yolk increased from the first to the second period (P<0.001) without changes afterwards, whereas it decreased in albumen from the second to the third period (P<0.001). Egg yolk Fe concentration was highest for the MBM containing diet supplemented with Fe-AA and lowest for the all-vegetable diet not supplemented with Fe, with all the other treatments being intermediate (P<0.001). Albumen Fe concentration increased when Fe was supplemented to diets containing MBM, but further increases depended on the use of Fe-AA (P<0.001). It is concluded that breeder hens have reduced hen day egg production when diets are not supplemented with Fe and that Fe supplementation can affect yolk and albumen contents depending on the presence of MBM in the diet. [Copyright &y& Elsevier]

Fresh eggs from hens fed diets supplemented with 4% linseed oil ( LO) or sunflower oil ( SO) were either directly submitted to pasteurisation, hard-boiling or scrambling processing, or first submitted to refrigerated storage at 4 °C for 60 day and then to processing. Fresh LO eggs showed higher ( P ≤ 0.05) proportions of monounsaturated fatty acids ( MUFAs) and n-3 polyunsaturated fatty acids ( PUFAs), but lower ( P ≤ 0.05) proportions of saturated fatty acids ( SFAs), PUFAs and n-6 PUFAs than the SO eggs. Storage decreased ( P ≤ 0.05) the proportion of PUFAs and increased ( P ≤ 0.05) that of MUFAs in egg yolks from both treatments. The pasteurisation process had no effect on the fatty acid composition of fresh eggs from both treatments, but increased ( P ≤ 0.05) n-6 PUFAs and decreased ( P ≤ 0.05) n-3 PUFAs in stored LO eggs. Hard-boiling and scrambling modified the fatty acid composition of fresh and stored eggs from both treatments by decreasing ( P ≤ 0.05) the proportion of PUFAs, particularly of the very long-chain n-3 eicosapentaenoic, docosapentaenoic and docosahexaenoic PUFAs. LO eggs showed a higher susceptibility to fatty acid modification upon processing as compared to the SO eggs. [ABSTRACT FROM AUTHOR]

Abstract: The health benefits of omega-3 polyunsaturated fatty acids (n−3 PUFA) are generally recognized. Unfortunately, in most western countries, the recommended daily intake of these compounds is rarely met. Therefore, enrichment of commonly occurring foods can boost intake of these fatty acids. In this regard, eggs are an interesting target, as they form an integral part of the diet. Their n−3 PUFA profile can be modified through feed supplementation. A traditional n−3 PUFA source to be added to hens'' diet is flaxseed, a plant source rich in α-linolenic acid. Alternatively, hens are often fed fish oil, which is rich in long chain n−3 PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). A more recent trend is feed supplementation with microalgae as a source of EPA and/or DHA. In this paper, recent scientific literature concerning n−3 PUFA enrichment in eggs is reviewed, giving an overview of advantages and disadvantages of the different approaches. [Copyright &y& Elsevier]

1. Egg size is often used as a proxy of egg quality although size and composition may vary, e.g. in insects egg size usually decreases as female ages. Whether this decrease in size reflects reduced concentrations of essential nutrients such as lipids and proteins of eggs laid by ageing females, or does reduced size per se explain often observed lower fitness of later laid eggs is poorly explored. 2. Egg properties were compared with fitness parameters of offspring laid on the first and fourth night during the oviposition period of a capital breeding moth, Cleorodes lichenaria (Hufnagel). The study aim was to explore whether decreased egg size is caused by decreased provisioning into later laid eggs measured as egg protein and lipid concentration, and whether it results in lower fitness of later laid offspring. 3. The fresh and dry weight of eggs decreased over the oviposition period, but the protein and lipid concentration remained constant. Survival of larvae was lower among the fourth night laid offspring on a low quality host Parmelia sulcata Taylor compared to a high quality host Ramalina fraxinea (L.) Ach. No differences were observed in egg fertility or hatchability, neonate survival without food and pupal mass between the offspring produced on different nights. 4. Decreased survival of offspring produced later was rather attributable to absolute provisioning (i.e. lower weight of eggs) than relative provisioning (i.e. decreased concentrations of nutrients in eggs). It is argued that lower survival of later laid smaller eggs on low quality diet is likely attributable to physical and chemical characteristics of host lichens and/or physical properties of tiny neonate larvae. [ABSTRACT FROM AUTHOR]

Objective. The application of the ovarian rest technique on brown egg layer birds was evaluated in this investigation as well as the effect of age and feed duration withdrawal have over their productive behavior. Materials and method. 840 Hy Line Brown hens at 64 weeks of age, evaluating three ages (65, 70 and 75 weeks) and three feed withdrawal periods (5, 10 and 15 days) in a completely randomized, nested, fixed and balanced effects model was used. The calcium consumption during feed withdrawal (g/bird/day), percentage of production, egg weight (g), conversion per egg mass and eggs per housed hen were evaluated. Results. The age factor presented a significant effect (p<0.05) for food consumption, day of the first egg laid post-molting, days without production, day of return to 50% of the production post-molting, egg weight, number of eggs average, egg mass, conversion and (p<0.01) production percentage. After comparing the control treatments, the 75-5 treatment presented a significant effect (p<0.05) for food consumption, average number of eggs, egg mass and conversion. Conclusions. Birds with a greater feed withdrawal period presented a greater unproductive post-molting period, greater weight loss and greater consumption of food which reflects on high conversion and could be defined as productive inefficiency. The comparison between lines showed that cease of production. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated the suppressive effect of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) transfer from the feed to the eggs of laying hens by using activated carbon as a feed additive. Four groups of six hens (White Leghorn egg-layers; age, 11weeks) were housed as two control groups and two exposure groups for a period of 20weeks. Two control groups were fed with either the basal feed “Control” or basal feed additing activated carbon “Control+C”. Another two exposure groups were fed with feed contaminated (about 6ng TEQ kg−1 feed) by standard solutions of PCDDs/PCDFs and DL-PCBs “Exposure” alone and contaminated feed adding activated carbon “Exposure+C”. There was no significant effect on each groups for the growth rate, biochemical blood components, and egg production: these were around the standard levels for poultry in general. Moreover the results in this study showed the availability of activated carbon as a feed additive owing to the reduction in the risk of food pollution by PCDDs/PCDFs and DL-PCBs. The concentration in the eggs of the Exposure group gradually increased following the start of egg-laying but reached a steady state after about 1month. In contrast, the concentration for the Exposure+C group was stationary and below the maximum EU level (6pgTEQg−1 fat). In comparison to the Exposure group, the Exposure+C group showed a significant decline in the percentage of bioaccumulation into the egg. This reduction due to activated carbon was also observed in the muscle and abdominal fat. The reductions were compound- and congener-dependent for DL-PCBs as follows: PCDDs/PCDFs, non-ortho-PCBs, and mono-ortho-PCBs were more than 90%, 80%, and 50%, respectively, irrespective of the type of tissues. Fat soluble vitamin concentrations in the eggs of the Exposure+C group showed lower trends than the Exposure group. The γ-tocopherol and α-tocopherol concentrations in eggs of Exposure+C group showed a significant reduction of about 40%. However, the addition of activated carbon into animal feed could obviate the remote potential for accidents causing unintentional food pollution with PCDDs/PCDFs and DL-PCBs. [Copyright &y& Elsevier]

Egg size is one of the fundamental parameters in the life histories of marine organisms. However, few studies have examined the relationships among egg size, composition, and energetic content in a phylogenetically controlled context. We investigated the associations among egg size, composition, and energy using a comparative system, geminate species formed by the closure of the Central American Seaway. We examined western Atlantic (WA) and eastern Pacific (EP) species in three echinoid genera, Echinometra, Eucidaris, and Diadema. In the genus with the largest difference in egg size between geminates (Echinometra), the eggs of WA species were larger, lipid rich and protein poor compared to the smaller eggs of their EP geminate. In addition, the larger WA eggs had significantly greater total egg energy and summed biochemical constituents yet significantly lower egg energy density (energy-per-unit-volume). However, the genera with smaller (Eucidaris) or no (Diadema) differences in egg size were not significantly different in summed biochemical constituents, total egg energy, or energy density. Theoretical models generally assume a strong tradeoff between egg size and fecundity that limits energetic investment and constrains life history evolution. We show that even among closely-related taxa, large eggs cannot be assumed to be scaled-up small eggs either in terms of energy or composition. Although our data comes exclusively from echinoid echinoderms, this pattern may be generalizable to other marine invertebrate taxa. Because egg composition and egg size do not necessarily evolve in lockstep, selective factors such as sperm limitation could act on egg volume without necessarily affecting maternal or larval energetics. [ABSTRACT FROM AUTHOR]

Abstract: The recent advent in single-molecule imaging and manipulation methods has made a significant impact on the understanding of molecular mechanisms underlying many essential cellular processes. Single-molecule techniques such as electron microscopy and DNA fiber assays have been employed to study the duplication of genome in eukaryotes. Here, we describe a single-molecule assay that allows replication of DNA attached to the functionalized surface of a microfluidic flow cell in a soluble Xenopus leavis egg extract replication system and subsequent visualization of replication products via fluorescence microscopy. We also explain a method for detection of replication proteins, through fluorescently labeled antibodies, on partially replicated DNA immobilized at both ends to the surface. [Copyright &y& Elsevier]

A novel method for determining air cell location, embryo development, and eggshell defects in opaque thickshelled eggs was tested. Results demonstrated that a camcorder with IR "Night Shot" function performed significantly better (P < 0.05) than unaided visual determination of air cell location in Emu eggs. In addition, the Mini DVC camcorder unit was as accurate as the heavier, non-portable, and more expensive traditional IR candling units. Commercial ratite producers, waterfowl biologists, and others working with opaque thickshelled eggs may benefit from this research. [ABSTRACT FROM AUTHOR]

The evolution of the egg is dynamic, and eggs have numerous species-specific properties across vertebrates and invertebrates. Interestingly, although the structure and function of the egg have remained relatively conserved over time, some constituents of the egg's extracellular barriers are undergoing rapid evolution. In this article, we review current ideas regarding sperm-egg interactions, discuss genetic approaches used to elucidate egg gene functions, and highlight the interesting differences that have evolved across taxa. We suggest that the rapid evolution of egg components and the mechanisms behind sperm-egg interactions are integrally connected, and delve in depth into each component of the egg's extracellular matrices. Finally, we discuss the promising future of reproductive research and how high-throughput genomics and proteomics have the potential to revolutionize the field and provide new evidence that will challenge previously held views about the fertilization process. [ABSTRACT FROM AUTHOR]

Para determinar el efecto que tiene en el contenido de colesterol del huevo la adición del alga marina (AM) Sargassum spp. en la dieta de gallinas ponedoras, se utilizaron 225 gallinas Leghorn, de 19 semanas de edad, distribuidas al azar en cinco tratamientos (0, 2, 4, 6 y 8 % del alga marina). El experimento tuvo una duración de cinco semanas, durante las que se registraron las variables productivas. La calidad física se evaluó en 75 huevos por tratamiento. Se tomaron 35 piezas de cada tratamiento para realizar el análisis del colesterol en huevo (yema+albúmina) por cromatografía de gases. Los datos se analizaron mediante ANOVA y se aplicó la prueba de Tukey para la comparación de medias (P < 0.05). Los resultados mostraron que con 4, 6 y 8 % de AM la producción de huevo se redujo y el color de la yema se incrementó. Las concentraciones de colesterol (mg 100 g-1 huevo fresco) fueron: 416.28 (0 % AM), 396.77 (2 % AM), 363.35 (4 % AM), 309.05 (6 % AM) y 338.76 (8 % AM). Se concluye que adicionar 4, 6, 8% del alga Sargassum spp. en la dieta de gallinas ponedoras reduce significativamente el contenido de colesterol en el huevo y afecta favorablemente el color de la yema. [ABSTRACT FROM AUTHOR]

Para evaluar el efecto de cuatro niveles de inclusión (0, 3.3, 6.6 y 10 %) de harina de semilla de calabaza (Cucurbita maxima) en el colesterol total y ácidos grasos de huevos de gallinas ponedoras, se ubicaron en pleno pico de puesta 160 gallinas White Leghorn (Híbrido L-33) durante 91 d, según diseño completamente aleatorizado. Se aplicó análisis de varianza de clasificación simple, excepto para la concentración de extracto etéreo, donde se utilizó el análisis factorial con cuatro tratamientos y 20 repeticiones. La concentración de extracto etéreo en el huevo se incrementó por efecto de las semanas de puesta y los niveles de inclusión de harina de semilla de calabaza (31.90 a 36.15 %). Esta oleaginosa enriqueció al huevo en ácidos grasos octadecanoico (152 a 450 mg/100 g), oleico (1282 a 1918 mg/100 g), linoleico (22 a 667 mg/100 g), α-linolénico (457 a 649 mg/100 g); mientras que redujo la cantidad de ácido araquidónico (62 a 50 mg/100 g). Se encontró menor relación de los ácidos grasos saturados/poliinsaturados (0.18 a 0.13) y omega 6/omega 3 (7.65 a 6.47). También la inclusión de este alimento disminuyó el colesterol total en 28 a 30 mg/huevo con respecto al control. Se recomienda incluir hasta 10 % de harina de semilla de calabaza en las dietas de gallinas ponedoras para incrementar el extracto etéreo y los ácidos grasos benéficos y reducir el colesterol total y los ácidos grasos perjudiciales en los huevos. [ABSTRACT FROM AUTHOR]

This paper is a review of available literature concerning nutrition value of egg of different kind of poultry. The article contains a comparative analysis of the literature data basic chemical composition, essential amino acids composition of protein, profile of fatty acid, content of cholesterol, mineral substances and vitamins of hen’s, duck’s, goose’s, ostrich’s and quail’s eggs. Taking into consideration the content of essential amino acids, vitamins from B groups, and the micro- and macroelements contents, quail eggs are characterized by a higher nutritional value compared to the eggs of hens. Furthermore the goose eggs’ are characterized by being most similar to recommend PUFA n-6/n-3 ratio and are better because of the fatty acid composition in comparison to the eggs of other birds’ species. [ABSTRACT FROM AUTHOR]

The equilibrium stress of egg white (EW) and ovalbumin (OV) gels using the statistical theory of rubber elasticity suggested that 3.9 covalent disulfide cross-links per OV molecule were formed on gelling. DTNB and PCMB reacted with approximately 4 sulfhydryls of OV in 2% SDS and/or at 82°C. Moreover, the equivalent of 3 secondary bonds, calculated from the initial stress and presumably a composite of numerous weak secondary bonds, contributed significantly to the protein gel stress. [ABSTRACT FROM AUTHOR]

A new approach, alternative to currently available methods, for studying cholesterol oxidation in egg powder is reported. The quantitative analysis of cholesterol oxides was carried out by high-resolution proton nuclear magnetic resonance. (1H-NMR). The following oxides were isolated from spray-dried egg powder by rapid chromatographic procedures and detected by selecting "marker" 1H-NMR signals: 7-ketocholesterol, 7α-hydroxy-cholesterol, 7β-hydroxy-cholesterol, cholesterol-α-epoxide and cholesterol-β-epoxide. The quantified cholesterol derivatives ranged from 4.9 to 9.1 ppm with a detection limit of 0.3 ppm (5 μg from 16g of matrix). The main usefulness of the method should be in investigating intermediates and products due to chemical transformation of cholesterol during storage and heating of foodstuffs. [ABSTRACT FROM AUTHOR]

The Flory gelation theory and a new protein gelation model were used to investigate the aggregation reactions of egg albumen and ovalbumin. Results showed that 178 to 267 ovalbumin monomers were required to establish the initial ovalbumin gel at the gel point temperature, 81°C. The gel point temperature for egg albumen was 72°C by the Instron and 60°C by protein solubility. The values of the activation energy rate constants for the formation of the different aggregates in the pre-gel stage suggested that the larger ovalbumin aggregates were more reactive than the smaller ones. [ABSTRACT FROM AUTHOR]

The effect of the intake of 3-14 eggs/wk on biochemical risk markers of coronary heart disease (CHD) was examined in 70 young men who followed a high-fat diet. The study consisted of a run-in phase during which all subjects ate 3 eggs/wk for 2 mo and an experimental phase during which a reference group continued eating 3 eggs/wk and two experimental groups ate either 7 or 14 eggs/wk for 5 mo. The mean coefficients of variation in total plasma cholesterol (5.4-7.4%) were similar in all three groups and were larger than the mean changes of 0.2-5.6% in plasma cholesterol from baseline to end in the experimental groups. Except for increased lecithin-cholesterol acyltransferase activities and total serum protein concentrations, no significant differences in lipoproteins or coagulation factors occurred between groups. It seems that egg intake in this range did not influence CHD risk markers in these subjects. Recommendations to lower risk should probably concentrate on a reduction in fat and not cholesterol intake. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effect of storage temperature of fresh eggs on the sensory evaluation of boiled eggs. 240 Hi-Line shell eggs were stored at 4, 25 and 30°C for 6 days. 10 eggs from the 0, 3rd and 6th day of storage were randomly to measure Haugh unit (HU), egg white height and egg white pH value. The results showed that the HU and egg white height of 30, 25 and 4°C treatments at 0, 3rd and 6th day were decreased with increasing storage days, but egg white pH values were increased with storage day's increase. On the 6th day of storage, took 50 eggs from all treatments to boil 95 - 100°C for 5 min, then simmer for 10 min and compared with the fresh eggs (eggs laid on that day). Sensory evaluation used 5-scales and the items included peeling ability, egg surface, fishy smell, chew-feel and total acceptance. The peeling ability and egg surface scores results showed, 4, 25 and 30°C treatments were significantly better than the fresh eggs, but 25 and 30°C treatments were significantly better than 4°C treatment (P < 0.01). The chew-feel and the total acceptance scores were the highest in the 30°C treatment, and the lowest in the fresh eggs (P < 0.01). In conclusion, the boiled eggs made from the fresh eggs were hard to peel, and the total acceptance was the highest in the treatment stored at 30°C for 6 days. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Animal Science is the property of Chinese Society of Animal Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)